UT LEVEL II & III by Vishal Sir Non destruction testing
trantien2407
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Jul 08, 2024
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About This Presentation
UT LEVEL II & III by Vishal Sir.pdf
Slide Content
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
APPLICATION, TRAINING €
CERTIFICATION.
METHOD LEVEL Ihé. III
APPLICATION, TRAINING €
CERTIFICATION.
Course Contains
. Ultrasonic Principles.
Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
Ultrasonic Transducers And Standard Reference Blocks.
Bo fo Nk Ga CU > OM ON O
. Immersion Inspection.
10.Ultrasonic Contact Testing and Shell’s Law
11.Applications Of Angle Beam Contact Testing.
12.Nonrelevant Ultrasonic Indications:
13.Discontinuities, Their Origin And Types.
. Ultrasonic Principles.
Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
Ultrasonic Transducers And Standard Reference Blocks.
Bo fo Nk Ga CU > OM ON O
. Immersion Inspection.
10.Ultrasonic Contact Testing and Shell’s Law
11.Applications Of Angle Beam Contact Testing.
12.Nonrelevant Ultrasonic Indications:
13.Discontinuities, Their Origin And Types.
SERVICES
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXevTUaiRmQin1oCxQ
> LinkedIn :- Vishal Dhameliya WETRASONIC TESTING
https://www.linkedin.com/in/vishal-dhameliya-07605a4a/Y. = = 1.1 & ta
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXevTUaiRmQin1oCxQ
> LinkedIn :- Vishal Dhameliya WETRASONIC TESTING
https://www.linkedin.com/in/vishal-dhameliya-07605a4a/Y. = = 1.1 & ta
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
Chapter 1:- Application, Training & Certification.
> Qualification and Certification of NDT Personnel in accordance with this Recommended Practice SNT-TC-1A 2020
> is applicable to each of the following methods:
> Qualification and Certification of NDT Personnel in accordance with this Recommended Practice SNT-TC-1A 2020
> is applicable to each of the following methods:
OTraining and certification
> It is important that the technician and supervisor be qualified in the Ultrasonic Testing method before the
technique is used and test results evaluated.
> The American society for nondestructive testing recommends the use of its document recommended practice
no. SNT-TC-1A 2020.
> This document provides the employer with the necessary guidelines to properly qualify and certify the not
technician in all methods.
> To comply with this document the employer must establish a "written practice" which describes in detail how
the technician will be trained, examined, and certified.
> The student is advised to study Latest edition of SNT-TC-1A 2020 to determine the recommended number of
hours of classroom instruction and months of experience necessary to be certified as a Ultrasonic Testing
technician.
Otevels of qualification
> In the process of being initially trained, qualified and certified, an individual should be considered a
trainee.
> Atrainee should work with a certified individual. The trainee shall not independently conduct, interpret,
evaluate, or report the results of any NDT test.
> It is important that the technician and supervisor be qualified in the Ultrasonic Testing method before the
technique is used and test results evaluated.
> The American society for nondestructive testing recommends the use of its document recommended practice
no. SNT-TC-1A 2020.
> This document provides the employer with the necessary guidelines to properly qualify and certify the not
technician in all methods.
> To comply with this document the employer must establish a "written practice" which describes in detail how
the technician will be trained, examined, and certified.
> The student is advised to study Latest edition of SNT-TC-1A 2020 to determine the recommended number of
hours of classroom instruction and months of experience necessary to be certified as a Ultrasonic Testing
technician.
Otevels of qualification
> In the process of being initially trained, qualified and certified, an individual should be considered a
trainee.
> Atrainee should work with a certified individual. The trainee shall not independently conduct, interpret,
evaluate, or report the results of any NDT test.
OThree basic levels of qualification are as follows:
+ NDT LEVEL I:NDT Level | individual should have sufficient technical knowledge and skill to be qualified to
properly perform specific standardizations, specific NDT, and specific evaluation for acceptance or rejection
determinations according to written instruction and to record result . He should receive the necessary
instruction and supervision from a certified NDT LEVEL I! or level Ill individual.
+ NDT LEVEL II: NDT Level Il individual should have sufficient technical knowledge and skill to be qualified to set up
and standardize equipment and to interpret and evaluate results with respect to applicable codes, standards and
specifications. He should be thoroughly familiar with the scope and limitations of the methods for which qualified
and should exercise assigned responsibility for on the job training and guidance of trainees and NDT LEVEL |
personnel. The NDT LEVEL Il should be able to organize and report the results of NDT tests.
+ NDT LEVEL III: He should be capable of developing, qualifying, and approving procedures, establishing and approving
techniques, interpreting codes, standards, specification and procedures; and designating the particular NDT methods,
techniques and procedures to be used. The NDT level III should have sufficient practical background in applicable materials,
fabrication and product technology to establish techniques and to assist in establishing acceptance criteria when none are
otherwise available.
+ NDT LEVEL I:NDT Level | individual should have sufficient technical knowledge and skill to be qualified to
properly perform specific standardizations, specific NDT, and specific evaluation for acceptance or rejection
determinations according to written instruction and to record result . He should receive the necessary
instruction and supervision from a certified NDT LEVEL I! or level Ill individual.
+ NDT LEVEL II: NDT Level Il individual should have sufficient technical knowledge and skill to be qualified to set up
and standardize equipment and to interpret and evaluate results with respect to applicable codes, standards and
specifications. He should be thoroughly familiar with the scope and limitations of the methods for which qualified
and should exercise assigned responsibility for on the job training and guidance of trainees and NDT LEVEL |
personnel. The NDT LEVEL Il should be able to organize and report the results of NDT tests.
+ NDT LEVEL III: He should be capable of developing, qualifying, and approving procedures, establishing and approving
techniques, interpreting codes, standards, specification and procedures; and designating the particular NDT methods,
techniques and procedures to be used. The NDT level III should have sufficient practical background in applicable materials,
fabrication and product technology to establish techniques and to assist in establishing acceptance criteria when none are
otherwise available.
> The SNT-TC-1A document recommends that NDT LEVEL I and NDT LEVEL Il technicians be examined in the
following areas:
A. General examination
B. Specific examination
C. Practical examination
The SNT-TC-1A document recommends that NDT LEVEL Ill personnel be examined in the following areas:
>
A. Basic examination
B. Method examination
E
Specific examination
+ ASNT PROVIDES A SERVICE to the industry by providing LEVEL Ill examinations in the BASIC AND METHOD
AREAS. Because of the individual requirements of the many industries using NDT, the SPECIFIC EXAMINATION
is still the RESPONSIBILITY OF THE EMPLOYER.
following areas:
A. General examination
B. Specific examination
C. Practical examination
The SNT-TC-1A document recommends that NDT LEVEL Ill personnel be examined in the following areas:
>
A. Basic examination
B. Method examination
E
Specific examination
+ ASNT PROVIDES A SERVICE to the industry by providing LEVEL Ill examinations in the BASIC AND METHOD
AREAS. Because of the individual requirements of the many industries using NDT, the SPECIFIC EXAMINATION
is still the RESPONSIBILITY OF THE EMPLOYER.
SAMPLE CERTIFICATE-
FOR EXAMPLE-
AL DHAMELIYA
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ULTRASONI TESTING,
Trans Eau and Emi «pere rpc of
AMERICAN! ON TESTING
SST-TC-1A (2020 EDITION)
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FOR EXAMPLE-
AL DHAMELIYA
us filed she coco reparements oud ls demoted
E
mm
ULTRASONI TESTING,
Trans Eau and Emi «pere rpc of
AMERICAN! ON TESTING
SST-TC-1A (2020 EDITION)
Wong suc ul the enomminen and cafe to
A
‘ied the craton round hs demora
Rags y ace gins the cxammaion aud ead to
‘Nor LEvEL-u
Cranes Case et Excma 4 pere rp of
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NG
Peer
Experience
LENS Minimum hours in
Total hours
method or R
a in NDT
technique
a a A I 40 210 400
1 | Acoustic emission testing N 40 630 1200
1 N 40 210 400
m Ac field measurement 40 630 1200
a 1 \ 40 210 400
2 | Electromagnetic testing m Eddy current testing 40 630 1200
I 4 A 40 210 400
m Remote field testing 40 630 1200
. I 8 60 120
3 | Ground penetrating radar N 20 420 800
- ; 1 40 240 460
4 | Guided wave testing N 40 240 460
LENS Minimum hours in
Total hours
method or R
a in NDT
technique
a a A I 40 210 400
1 | Acoustic emission testing N 40 630 1200
1 N 40 210 400
m Ac field measurement 40 630 1200
a 1 \ 40 210 400
2 | Electromagnetic testing m Eddy current testing 40 630 1200
I 4 A 40 210 400
m Remote field testing 40 630 1200
. I 8 60 120
3 | Ground penetrating radar N 20 420 800
- ; 1 40 240 460
4 | Guided wave testing N 40 240 460
Trainin Experience
Examination method Technique
= ELSA Minimum hours in | Total hours
method or in NDT
technique
Laser methods testing profilometry 70 130
Il 24 140 260
1 Holography/stereograph 40 210 260
fy 40 630 400
6 Leak testing i} Bubble leak testing 2) 3 15
Il 4 35 80
i Pressure change leak 24 105 200
I testing 16 280 530
I Halogen diode leak 12) 05 200
" testing 8 280 530
ar
| Mass spectrometer leak 40 280 530
I} testing 24 420 800
El Liquid penetrant testing I 4 70 130
I 8 140 270
Examination method Technique
= ELSA Minimum hours in | Total hours
method or in NDT
technique
Laser methods testing profilometry 70 130
Il 24 140 260
1 Holography/stereograph 40 210 260
fy 40 630 400
6 Leak testing i} Bubble leak testing 2) 3 15
Il 4 35 80
i Pressure change leak 24 105 200
I testing 16 280 530
I Halogen diode leak 12) 05 200
" testing 8 280 530
ar
| Mass spectrometer leak 40 280 530
I} testing 24 420 800
El Liquid penetrant testing I 4 70 130
I 8 140 270
Examination method
Training
Experience
Technique me =
Minimum hours in Total hours
method or technique | in NDT
Magnetic flux leakage 70 130
'" alga 210 400
9 Magnetic particle testing | 12 70 130
Il 8 210 400
10 | Microwave technology testing 1 40 210 400
U 40 630 1200
11 | Neutron radiographic testing 1 28 420 800
il 40 1680 2400
12 | Radiographic testing 1 Radiography 40 210 400
ul 40 630 1200
| Computed radiography 40 2101 400
ll 40 630 1200
1 Computed tomography 40 210 400
ll 40 630 1200
! Digital radiography 40 210 400
I 40 630 1200
Training
Experience
Technique me =
Minimum hours in Total hours
method or technique | in NDT
Magnetic flux leakage 70 130
'" alga 210 400
9 Magnetic particle testing | 12 70 130
Il 8 210 400
10 | Microwave technology testing 1 40 210 400
U 40 630 1200
11 | Neutron radiographic testing 1 28 420 800
il 40 1680 2400
12 | Radiographic testing 1 Radiography 40 210 400
ul 40 630 1200
| Computed radiography 40 2101 400
ll 40 630 1200
1 Computed tomography 40 210 400
ll 40 630 1200
! Digital radiography 40 210 400
I 40 630 1200
Examination method
NDT
Technique
Training
Experience
SE Minimum hours in | Total hours
method or technique | in NDT
13 | Thermal/infrared testing | 32 210 400
1 Building diagnostics 34 1260 1800
I Electrical and mechanical 34 1260 1800
M Materials testing 34 1260 1800
14 | Ultrasonic testing 1 40 210 400
I 40 630 1200
il Full matrix capture 80 320 n/a
11 | Phased array ultrasonic 80 320 n/a
testing
iT} Time of flight diffraction 40 320 n/a
15 | Vibration analysis | 24 420 800
il 72 1680 2400
16 | Visual testing I 8 70 130
li 16 140 270
NDT
Technique
Training
Experience
SE Minimum hours in | Total hours
method or technique | in NDT
13 | Thermal/infrared testing | 32 210 400
1 Building diagnostics 34 1260 1800
I Electrical and mechanical 34 1260 1800
M Materials testing 34 1260 1800
14 | Ultrasonic testing 1 40 210 400
I 40 630 1200
il Full matrix capture 80 320 n/a
11 | Phased array ultrasonic 80 320 n/a
testing
iT} Time of flight diffraction 40 320 n/a
15 | Vibration analysis | 24 420 800
il 72 1680 2400
16 | Visual testing I 8 70 130
li 16 140 270
O VISION EXAMINATIONS
Near-Vision Acuity. The examination should ensure natural or corrected near-distance acuity in at least one
eye such that the applicant is capable of reading a minimum of Jaeger Number 2 (J2) or equivalent type and
size letter at the distance designates on the chart but not less than 12 in. (30.5 cm) on a standard Jaeger test
chart. The ability to perceive an Ortho-Rater minimum of 8 or similar test pattern is also acceptable. This
should be administered annually.
Color Contrast Differentiation. The examination should demonstrate the capability of distinguishing and
differentiating contrast among colors or shades of gray used in the method as determined by the employer.
This should be conducted upon initial certification and at five-year intervals thereafter.
Vision examinations expire on the last day of the month of expiration.
O INTERRUPTED SERVICE
The employer's written practice should include rules covering the types and duration of interrupted service
that requires reexamination and recertification.
The written practice should specify the requirements for reexamination and/or recertification for the
interrupted service.
Near-Vision Acuity. The examination should ensure natural or corrected near-distance acuity in at least one
eye such that the applicant is capable of reading a minimum of Jaeger Number 2 (J2) or equivalent type and
size letter at the distance designates on the chart but not less than 12 in. (30.5 cm) on a standard Jaeger test
chart. The ability to perceive an Ortho-Rater minimum of 8 or similar test pattern is also acceptable. This
should be administered annually.
Color Contrast Differentiation. The examination should demonstrate the capability of distinguishing and
differentiating contrast among colors or shades of gray used in the method as determined by the employer.
This should be conducted upon initial certification and at five-year intervals thereafter.
Vision examinations expire on the last day of the month of expiration.
O INTERRUPTED SERVICE
The employer's written practice should include rules covering the types and duration of interrupted service
that requires reexamination and recertification.
The written practice should specify the requirements for reexamination and/or recertification for the
interrupted service.
reserved for Augustus to relinquish the ambitious design of subduing the
Whole earth, and to introduce a spirit of moderation into the public councils.
Inclined to peace by his temper and situation, it was very easy for him to
discover that Rome, in her present exalted situation, had much less to
hope than to fear from the chance of arms; and that, In the prosecution of
No. 6.
1.00M
ery day more difficult, the event more
ion more precarious, and less beneficial.
The expérience of Augustus added weight to these salutary reflec
dons, and effectually convinced him that, by the prudent vigor of
No. 6.
1.25M
is counsels, it would be easy to secure every concession which
the safety or the dignity of Rome might require from the most
formidable barbarians. Instead of exposing his person or his
legions to the arrows of the Parthians, he obtained, by an honor-
No. 7.
1.50M
able treaty, the restitution of the standards and prisoners
which had been taken in the defeat of Crassus. His gen-
erals, in the early part of his reign, attempted the reduction
of Ethiopia and Arabia Felix. They marched near a thou-
No. 8.
1.75M
les to the south of the tropic; but the heat of
invaders, and protected
regions
sand
the climate soon repelled the
the unwarlike natives of those sequestered
No. 9.
2.00M
The northern countries of Europe scarcely de-
served the expense and labor of conquest.
The forests and morasses of Germany were
No. 10.
2.26M
filled with a hardy race of barbarians
who despised life when it was separated
from freedom; and though, on the first
No. 11.
2.60M
they seemed to yield
weight of the Roman
they soon, by a signal
attack,
to the
power,
Whole earth, and to introduce a spirit of moderation into the public councils.
Inclined to peace by his temper and situation, it was very easy for him to
discover that Rome, in her present exalted situation, had much less to
hope than to fear from the chance of arms; and that, In the prosecution of
No. 6.
1.00M
ery day more difficult, the event more
ion more precarious, and less beneficial.
The expérience of Augustus added weight to these salutary reflec
dons, and effectually convinced him that, by the prudent vigor of
No. 6.
1.25M
is counsels, it would be easy to secure every concession which
the safety or the dignity of Rome might require from the most
formidable barbarians. Instead of exposing his person or his
legions to the arrows of the Parthians, he obtained, by an honor-
No. 7.
1.50M
able treaty, the restitution of the standards and prisoners
which had been taken in the defeat of Crassus. His gen-
erals, in the early part of his reign, attempted the reduction
of Ethiopia and Arabia Felix. They marched near a thou-
No. 8.
1.75M
les to the south of the tropic; but the heat of
invaders, and protected
regions
sand
the climate soon repelled the
the unwarlike natives of those sequestered
No. 9.
2.00M
The northern countries of Europe scarcely de-
served the expense and labor of conquest.
The forests and morasses of Germany were
No. 10.
2.26M
filled with a hardy race of barbarians
who despised life when it was separated
from freedom; and though, on the first
No. 11.
2.60M
they seemed to yield
weight of the Roman
they soon, by a signal
attack,
to the
power,
U Recertification
> All levels of NDT personnel shall be recertified periodically in accordance with one of the following criteria:
Evidence of continuing satisfactory technical performance.
The recommended maximum recertification intervals are 5 years for all certification levels. Certifications expire
on the last day of the month of expiration.
When new techniques are added to the employer's written practice, NDT Level Ill personnel should receive
applicable training, take applicable examinations and obtain the necessary experience, such that the NDT Level
Ill meets the requirements of the new techniques in above discussion, prior to their next recertification date, in
the applicable method.
> All levels of NDT personnel shall be recertified periodically in accordance with one of the following criteria:
Evidence of continuing satisfactory technical performance.
The recommended maximum recertification intervals are 5 years for all certification levels. Certifications expire
on the last day of the month of expiration.
When new techniques are added to the employer's written practice, NDT Level Ill personnel should receive
applicable training, take applicable examinations and obtain the necessary experience, such that the NDT Level
Ill meets the requirements of the new techniques in above discussion, prior to their next recertification date, in
the applicable method.
General Questions Specific Questions
Method/Technique
Level | Level Il Level | Level Il
a Acoustic emission testing 40 40 20 20
à Electromagnetic testing
3 Alternating current field measurement 40 40 20 20
4 Eddy current testing 40 40 20 20
5 Remote field testing 30 30 20 20
6 Ground penetrating radar 30 40 20 20
7 Guided wave testing 40 40 20 20
8 Laser methods testing
9 profilometry 30 30 20 20
10 Holography/ shearography 30 30 20 20
ar Leak testing
12 Bubble leak testing 20 20 us 15
13 pressure change leak testing 20 20 15 15
14 Halogen diode leak testing 20 20 15 ls
15 Mass spectrometer leak testing 20 20 20 40
16 Liquid penetrant testing 40 40 20 20
Method/Technique
Level | Level Il Level | Level Il
a Acoustic emission testing 40 40 20 20
à Electromagnetic testing
3 Alternating current field measurement 40 40 20 20
4 Eddy current testing 40 40 20 20
5 Remote field testing 30 30 20 20
6 Ground penetrating radar 30 40 20 20
7 Guided wave testing 40 40 20 20
8 Laser methods testing
9 profilometry 30 30 20 20
10 Holography/ shearography 30 30 20 20
ar Leak testing
12 Bubble leak testing 20 20 us 15
13 pressure change leak testing 20 20 15 15
14 Halogen diode leak testing 20 20 15 ls
15 Mass spectrometer leak testing 20 20 20 40
16 Liquid penetrant testing 40 40 20 20
Sr.
Method/Technique
General Questions
Specific Questions
Level | Level Il Level | Level II
17 | Magnetic flux leakage testing 20 20 20 15
18 | Magnetic particle testing 40 40 20 20
19 | Microwave technology testing 40 40 20 20
20 | Neutron radiographic testing 40 40 20 20
21 | Radiographic testing
22 | Radiography 40 40 20 20
23 | Radiographic film interpretation non- m a
radiographer
24 | Radiographic film interpretation 20 15
radiographer(certified RT NDT level I)
25 | Computed radiography 40 40 20 20
26 | Computed tomography 40 40 20 20
27 | Digital radiography 40 40 20 20
28 | Thermal/Infrared testing 40 20
29 | Building diagnostics 50 40
30 | Electrical and mechanical testing 50 40
Method/Technique
General Questions
Specific Questions
Level | Level Il Level | Level II
17 | Magnetic flux leakage testing 20 20 20 15
18 | Magnetic particle testing 40 40 20 20
19 | Microwave technology testing 40 40 20 20
20 | Neutron radiographic testing 40 40 20 20
21 | Radiographic testing
22 | Radiography 40 40 20 20
23 | Radiographic film interpretation non- m a
radiographer
24 | Radiographic film interpretation 20 15
radiographer(certified RT NDT level I)
25 | Computed radiography 40 40 20 20
26 | Computed tomography 40 40 20 20
27 | Digital radiography 40 40 20 20
28 | Thermal/Infrared testing 40 20
29 | Building diagnostics 50 40
30 | Electrical and mechanical testing 50 40
General Questions Specific Questions
Sr. No. Method/Technique
Level | Level Il Level | Level Il
oul Materials testing 50 40
32 | Ultrasonic testing 40 40 20 20
33 Full matrix capture 40 30
34 Phased array ultrasonic testing 40 30
35 Time of flight diffraction 40 30
36 Digital thickness measurement 20 10
(numeric output only)
37 A-scan thickness measurement 30 15
38 Vibration analysis 40 40 20 60
39 Visual testing 40 40 20 20
Sr. No. Method/Technique
Level | Level Il Level | Level Il
oul Materials testing 50 40
32 | Ultrasonic testing 40 40 20 20
33 Full matrix capture 40 30
34 Phased array ultrasonic testing 40 30
35 Time of flight diffraction 40 30
36 Digital thickness measurement 20 10
(numeric output only)
37 A-scan thickness measurement 30 15
38 Vibration analysis 40 40 20 60
39 Visual testing 40 40 20 20
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
ULTRASONIC PRINCIPLES
METHOD LEVEL Ihé. III
ULTRASONIC PRINCIPLES
Course Contains
. Application, Training & Certification.
Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
. Ultrasonic Transducers And Standard Reference Blocks.
po oN DAH PF WN
|. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell's Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
. Application, Training & Certification.
Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
. Ultrasonic Transducers And Standard Reference Blocks.
po oN DAH PF WN
|. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell's Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya
https://www. linkedin.com/in/vishal-dhameliya-07605a4a/
"EST eg and NDT Creat Rena
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya
https://www. linkedin.com/in/vishal-dhameliya-07605a4a/
"EST eg and NDT Creat Rena
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
LULTRASONIC PRINCIPLES
> In ultrasonic testing we use something called "ultrasonic vibrations." We must know two facts about a vibration:
1. A vibration is a back and forth movement.
2. Avibration is energy in motion.
> A depression of a surface from its normal position is called a displacement.
RUBBER BALL
> In ultrasonic testing we use something called "ultrasonic vibrations." We must know two facts about a vibration:
1. A vibration is a back and forth movement.
2. Avibration is energy in motion.
> A depression of a surface from its normal position is called a displacement.
RUBBER BALL
> Vibrations pass through a solid material as a succession of particle displacements. This can be visualized as
shown below:
> The structure of a material is actually many small particles or groups of atoms.
> These particles have normal or rest positions, and can be displaced from these positions by some force. When
the force is removed, the particles will tend to return to their original positions.
> Energy is transmitted through a solid material by a series of small material displacements within the material.
shown below:
> The structure of a material is actually many small particles or groups of atoms.
> These particles have normal or rest positions, and can be displaced from these positions by some force. When
the force is removed, the particles will tend to return to their original positions.
> Energy is transmitted through a solid material by a series of small material displacements within the material.
> The transmission of ultrasonic vibrations through a material is related to the elastic properties of the material.
> If you tap a metal surface, the surface moves inward, causing a displacement.
THIN PLATE
PLATE STRUCK
LZ
A Fi WITH HAMMER
md ao
NS support
VIEW A VIEW B
> Since the metal is elastic the surface will tend to move back to its original (rest) position. The surface will also
move through the original position and move to a maximum distance in the opposite direction.
> This complete sequence of movements is defined as a cycle.
> If you tap a metal surface, the surface moves inward, causing a displacement.
THIN PLATE
PLATE STRUCK
LZ
A Fi WITH HAMMER
md ao
NS support
VIEW A VIEW B
> Since the metal is elastic the surface will tend to move back to its original (rest) position. The surface will also
move through the original position and move to a maximum distance in the opposite direction.
> This complete sequence of movements is defined as a cycle.
DIRECTION OF
DIRECTION OF BALL SWING
STRING STRING TRAVEL
8
STRING
BALL N :
BALL c
ONE
2 CYCLE
PENCIL PENCIL
> The time required for something to move through one complete cycle is called the period.
+ Example: if the swinging ball above moves over path ABCDE in one second, then the period of the cycle is one
second.
> The number of cycles in a given period of time is called the frequency.
+ Example: if the ball swings through three complete cycles in one second, then the frequency is 3 cps (cycles
per second).
DIRECTION OF BALL SWING
STRING STRING TRAVEL
8
STRING
BALL N :
BALL c
ONE
2 CYCLE
PENCIL PENCIL
> The time required for something to move through one complete cycle is called the period.
+ Example: if the swinging ball above moves over path ABCDE in one second, then the period of the cycle is one
second.
> The number of cycles in a given period of time is called the frequency.
+ Example: if the ball swings through three complete cycles in one second, then the frequency is 3 cps (cycles
per second).
> If you strike a drum, it has a frequency that is low, approximately 50 cps.
> The top note on the piano has a higher frequency, approximately 4100 cps.
VIBRATING PRONG
TUNING FORK
When we hit the When we playa Sound produced
drum, membrane guitar the string by vibrating
of drum vibrates on it makes to and prong of
producing sound. fro motion and tuning fork.
produces sound.
> The top note on the piano has a higher frequency, approximately 4100 cps.
VIBRATING PRONG
TUNING FORK
When we hit the When we playa Sound produced
drum, membrane guitar the string by vibrating
of drum vibrates on it makes to and prong of
producing sound. fro motion and tuning fork.
produces sound.
> The unit of frequency used to denote one cycle per second is Hertz (abbreviated Hz). one cycle per second
(CPS) is equal to one Hertz (Hz); 2 CPS = 2 Hz, ETC.
> Sound travels in metal as well as in air. Sound is a vibration and has a range of frequencies.
> Man can only hear vibrations (sound) up to about 20,000 Hz.
> However, sound from an ultrasonic testing unit is about 5,000,000 Hz. (5 megahertz).
> Vibrations above the human hearing range are called ultrasonic vibrations.
> The two terms, sound and vibrations, as we will use them will mean the same thing.
Human
Audible
Range
Infrasound OPEN; Ultrasound
20 Hz 20 kHz
y y
' Standard Advanced = ustic
Acoustic Well Birtuse Field.
Logging Velocity Backscatter
& Attenuation Measurement
Measurement Frequencies
Frequencies 30-200 kHz
3-30 kHz
(CPS) is equal to one Hertz (Hz); 2 CPS = 2 Hz, ETC.
> Sound travels in metal as well as in air. Sound is a vibration and has a range of frequencies.
> Man can only hear vibrations (sound) up to about 20,000 Hz.
> However, sound from an ultrasonic testing unit is about 5,000,000 Hz. (5 megahertz).
> Vibrations above the human hearing range are called ultrasonic vibrations.
> The two terms, sound and vibrations, as we will use them will mean the same thing.
Human
Audible
Range
Infrasound OPEN; Ultrasound
20 Hz 20 kHz
y y
' Standard Advanced = ustic
Acoustic Well Birtuse Field.
Logging Velocity Backscatter
& Attenuation Measurement
Measurement Frequencies
Frequencies 30-200 kHz
3-30 kHz
> The best way to define sound is to say that it is a vibration that transmits energy by a series of small material
displacements.
Human
Audible
Range
Infrasound A Ultrasound
20 Hz 20 kHz
y y
Standard Advanced Acoustic
Acoustic Well Diffuse Field,
Logging Velocity Backscatter
& Attenuation Measurement
Measurement Frequencies:
Frequencies: 30-200 kHz
3-30 kHz
displacements.
Human
Audible
Range
Infrasound A Ultrasound
20 Hz 20 kHz
y y
Standard Advanced Acoustic
Acoustic Well Diffuse Field,
Logging Velocity Backscatter
& Attenuation Measurement
Measurement Frequencies:
Frequencies: 30-200 kHz
3-30 kHz
JACK HAMMER
TRANSDUCER
> Ultrasonic testing is the process of applying ultrasonic sound to a specimen and determining its soundness, thickness, or
some physical property.
> The energy is originated in something called a "transducer" which causes material displacement wit
> Atransducer is a device that converts energy from one form to another.
jin the specimen.
+ Example: electrical energy to mechanical, or mechanical to electrical.
* A speaker in a radio converts electrical energy to a back and forth mechanical movement.
TRANSDUCER
> Ultrasonic testing is the process of applying ultrasonic sound to a specimen and determining its soundness, thickness, or
some physical property.
> The energy is originated in something called a "transducer" which causes material displacement wit
> Atransducer is a device that converts energy from one form to another.
jin the specimen.
+ Example: electrical energy to mechanical, or mechanical to electrical.
* A speaker in a radio converts electrical energy to a back and forth mechanical movement.
> The terms crystal and transducer are used interchangeably in this Chapter.
The ultrasound transducer
The ultrasound transducer from the side and front.
Acoustic insulation Acoua YS
ee layer
Matching layer Arrangement of
Piezoelectric piezoelectric crystals
crystals
The ultrasound transducer
The ultrasound transducer from the side and front.
Acoustic insulation Acoua YS
ee layer
Matching layer Arrangement of
Piezoelectric piezoelectric crystals
crystals
> View “A" below illustrates the “piezoelectric effect." Electrical energy is applied through two wires connected
to a crystal, causing the crystal to vibrate.
CRYSTA
| A U TRANSDUCER
ELECTRICAL ENERGY [mararıon N
WIRE
palo VIEW 8
> Electrical energy causes a piezoelectric crystal to expand and contract, forming mechanical vibrations.
> A piezoelectric transducer can also convert mechanical energy to electrical energy. Therefore, a transducer
can both send and receive energy.
SPECIMEN
|
TRANSDUCER NOTE:
SOUND IS REFLECTED
WITHIN SPECIMEN AND
RETURNS TO TRANSDUCER
VIEW B
to a crystal, causing the crystal to vibrate.
CRYSTA
| A U TRANSDUCER
ELECTRICAL ENERGY [mararıon N
WIRE
palo VIEW 8
> Electrical energy causes a piezoelectric crystal to expand and contract, forming mechanical vibrations.
> A piezoelectric transducer can also convert mechanical energy to electrical energy. Therefore, a transducer
can both send and receive energy.
SPECIMEN
|
TRANSDUCER NOTE:
SOUND IS REFLECTED
WITHIN SPECIMEN AND
RETURNS TO TRANSDUCER
VIEW B
> Energy transmitted by a transducer can be either pulsed or continuous energy, we will discussed this in detail
next chapter,
> Pulsed ultrasound is defined as short groups of transmitted vibrations before and after which the transducer
can act as a receiver.
> Steel, water and oil will transmit ultrasound very well, but air presents a problem.
TRANSDUCER
OIL
> Air is a poor transmitter of ultrasound because the particle density is so low that it is difficult to transmit
sound energy from particle to particle. That is why we put oil, grease or cellulose paste between the
transducer and the specimen.
> The particle density of a material helps determine the velocity of sound. The velocity of sound will change as
it moves from one medium to another as shown below. The elasticity of the material is also a factor.
next chapter,
> Pulsed ultrasound is defined as short groups of transmitted vibrations before and after which the transducer
can act as a receiver.
> Steel, water and oil will transmit ultrasound very well, but air presents a problem.
TRANSDUCER
OIL
> Air is a poor transmitter of ultrasound because the particle density is so low that it is difficult to transmit
sound energy from particle to particle. That is why we put oil, grease or cellulose paste between the
transducer and the specimen.
> The particle density of a material helps determine the velocity of sound. The velocity of sound will change as
it moves from one medium to another as shown below. The elasticity of the material is also a factor.
sobs soe e oe ATS
0.33 KM/SEC 1.48 KM/SEC 5.9 KM/SEC
Aır WATER STEEL
> Visualize that the balls shown above represent the internal structure of air, water and steel.
> The impulse moving through the row of balls can be compared to a pulse of ultrasonic sound.
ACOSTIC SOUND
MATERIALS. IMPEDANCE DENSITY
GRAM/CM? = SEC GRAM/CM?
Air 0.000033 X 10° 0.33 X 10° 0.001
Water 0.149 X 10° 1.49 X 10° 1.00
Aluminum 1.72 X 10° 6.35 X 10° 2.71
Steel 4.56 X 10° 5.85 X 10° 7.8
0.33 KM/SEC 1.48 KM/SEC 5.9 KM/SEC
Aır WATER STEEL
> Visualize that the balls shown above represent the internal structure of air, water and steel.
> The impulse moving through the row of balls can be compared to a pulse of ultrasonic sound.
ACOSTIC SOUND
MATERIALS. IMPEDANCE DENSITY
GRAM/CM? = SEC GRAM/CM?
Air 0.000033 X 10° 0.33 X 10° 0.001
Water 0.149 X 10° 1.49 X 10° 1.00
Aluminum 1.72 X 10° 6.35 X 10° 2.71
Steel 4.56 X 10° 5.85 X 10° 7.8
> Apractical example of the velocity of sound in different materials is shown below.
dite. * E | 5
ZZ
TRANSDUCER
STEEL
SPECIMEN
> It will take longer for the sound to travel through the water than through the steel. The sound velocity in steel is
approximately four times greater than in water.
> Awavelength is considered to be the distance between two successive displacements.
dite. * E | 5
ZZ
TRANSDUCER
STEEL
SPECIMEN
> It will take longer for the sound to travel through the water than through the steel. The sound velocity in steel is
approximately four times greater than in water.
> Awavelength is considered to be the distance between two successive displacements.
TRANSDUCER
WAVELENGTH
M ‘ Aa— M \ A M N A
A, N al A A
> The wavelength can also be defined as the distance a wave travels during one complete cycle.
TRANSDUCER
pipi
0000
VIEW A VIEW B
SOUND WAVE
> The symbol A is used to represent a wavelength and is called "lambda".
WAVELENGTH
M ‘ Aa— M \ A M N A
A, N al A A
> The wavelength can also be defined as the distance a wave travels during one complete cycle.
TRANSDUCER
pipi
0000
VIEW A VIEW B
SOUND WAVE
> The symbol A is used to represent a wavelength and is called "lambda".
> The illustration below shows a transducer vibrating at a fixed frequency (f) and transmitting sound waves into
the specimen.
VELOCITY ——
ket | WN dod
SOUND WAVES ——*=
TRANSDUCER
> These sound waves move at a fixed velocity (v) through the specimen.
> The wavelength can be changed if the frequency of the transducer vibration changes.
Vv VELOCITY
À = —— WAVELENGTH =
f FREQUENCY
> Example: you can shorten the wavelength by increasing the frequency.
> Wavelength is a ratio of a fixed value (velocity) divided by a variable (frequency).
> In practical situations, the smallest discontinuity you can find with ultrasonic testing is about 1/2 lambda
(wavelength). Therefore, to detect smaller defects, you will need transducers that produce higher
frequencies.
the specimen.
VELOCITY ——
ket | WN dod
SOUND WAVES ——*=
TRANSDUCER
> These sound waves move at a fixed velocity (v) through the specimen.
> The wavelength can be changed if the frequency of the transducer vibration changes.
Vv VELOCITY
À = —— WAVELENGTH =
f FREQUENCY
> Example: you can shorten the wavelength by increasing the frequency.
> Wavelength is a ratio of a fixed value (velocity) divided by a variable (frequency).
> In practical situations, the smallest discontinuity you can find with ultrasonic testing is about 1/2 lambda
(wavelength). Therefore, to detect smaller defects, you will need transducers that produce higher
frequencies.
> Example: what would be the smallest discontinuity that you could find in a steel specimen with a velocity of
6km/sec using a transducer with a frequency of 3 megahertz (mhz).
6 x 10° CM/SEC
3 MHz
= 2MILLIMETERS
> If the smallest defect detectable is 1/2 lambda, then the answer is 1 millimeter or 0.040 inches.
6km/sec using a transducer with a frequency of 3 megahertz (mhz).
6 x 10° CM/SEC
3 MHz
= 2MILLIMETERS
> If the smallest defect detectable is 1/2 lambda, then the answer is 1 millimeter or 0.040 inches.
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
ULTRASONIC TESTING METHODS
& EQUIPMENT CONTROLS.
METHOD LEVEL Ihé. III
ULTRASONIC TESTING METHODS
& EQUIPMENT CONTROLS.
Course Contains
1. Application, Training & Certification.
2. Ultrasonic Principles.
3. Ultrasonic Testing Methods & Equipment Controls.
Wave propagation, Reflection & Refraction.
Couplant , Ultrasonic Sound Energy & Materials Characteristics
4.
5°
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
1. Application, Training & Certification.
2. Ultrasonic Principles.
3. Ultrasonic Testing Methods & Equipment Controls.
Wave propagation, Reflection & Refraction.
Couplant , Ultrasonic Sound Energy & Materials Characteristics
4.
5°
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya ULTRASONIC TESTING
https://www.linkedin.cor/in/vishal-dhameliya-07605a4a/Y. METHOD LEVEL It $ Il
& EQUIPMENT CON Fr
> Dipesh Patel + +91 8155079565
> Vishal Dhameliya :- +91 9737177783
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya ULTRASONIC TESTING
https://www.linkedin.cor/in/vishal-dhameliya-07605a4a/Y. METHOD LEVEL It $ Il
& EQUIPMENT CON Fr
> Dipesh Patel + +91 8155079565
> Vishal Dhameliya :- +91 9737177783
CRT (CATHODE RAY TUBE)
MARKER) TIMER PULSER RECEIVER
CIRCUIT (rare Generator] [CIRCUIT AMPLIFIER
N N CIRCUIT
SWEEP TRANSDUCER
CIRCUIT gpRoB)
11
TEST 1
Kt (TO EACH CIRCUIT) SPECIMEN A ı
DISCONTINUIT #
o
BACK REFLECTION
MARKER) TIMER PULSER RECEIVER
CIRCUIT (rare Generator] [CIRCUIT AMPLIFIER
N N CIRCUIT
SWEEP TRANSDUCER
CIRCUIT gpRoB)
11
TEST 1
Kt (TO EACH CIRCUIT) SPECIMEN A ı
DISCONTINUIT #
o
BACK REFLECTION
MODSONIC EINSTEIN-II DGS
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> The Ultrasonic pulse echo instrument generates high voltage electrical pulses of short duration. These pulses
are applied to the transducer which converts them into mechanical vibrations that are applied to the material
being inspected.
> A large percentage of the sound is reflected from the front surface of the test part back to the transducer. The
remainder is reflected by the back surface or discontinuities.
> The sound reflected back to the transducer is converted back to electrical pulses, which are amplified and
displayed on the cathode ray tube (CRT) as vertical pulses.
> The A-scan display indicates the depth and the amplitude of the sound reflections from a discontinuity.
> The amplitude is a relative measure of the amount of reflected energy.
are applied to the transducer which converts them into mechanical vibrations that are applied to the material
being inspected.
> A large percentage of the sound is reflected from the front surface of the test part back to the transducer. The
remainder is reflected by the back surface or discontinuities.
> The sound reflected back to the transducer is converted back to electrical pulses, which are amplified and
displayed on the cathode ray tube (CRT) as vertical pulses.
> The A-scan display indicates the depth and the amplitude of the sound reflections from a discontinuity.
> The amplitude is a relative measure of the amount of reflected energy.
% There are two basic ultrasonic test systems:
SPECIMEN
PULSE-ECHO
CATHODE -RAY TUBE
7
COUPLANT
TRANSDUCER
NTINUITY
GENERATOR/INDICATOR DISCONTINUI
INSTRUMENT COAXIAL CABLE
PULSE-ECHO SYSTEM
THROUGH TRANSMISSION SPECIMEN FRANSOUCER
CATHODE-RAY TUBE
COUPLANT COUPLANT
TRANSMITTING
TRANSDUCER
_—.
DISCONTINUITY pa
GENERATOR/INDICATOR a
INSTRUMENT ‘COAXIAL CABLE > 7 -
THROUGH TRANSMISSION SYSTEM
SPECIMEN
PULSE-ECHO
CATHODE -RAY TUBE
7
COUPLANT
TRANSDUCER
NTINUITY
GENERATOR/INDICATOR DISCONTINUI
INSTRUMENT COAXIAL CABLE
PULSE-ECHO SYSTEM
THROUGH TRANSMISSION SPECIMEN FRANSOUCER
CATHODE-RAY TUBE
COUPLANT COUPLANT
TRANSMITTING
TRANSDUCER
_—.
DISCONTINUITY pa
GENERATOR/INDICATOR a
INSTRUMENT ‘COAXIAL CABLE > 7 -
THROUGH TRANSMISSION SYSTEM
> Pulse-echo is the most widely used ultrasonic system.
> Short evenly timed pulses of ultrasonic waves are transmitted into the material being tested.
> These pulses reflect from discontinuities in their path, or from any boundary that they strike.
> The received reflections are then displayed on a cathode ray tube (CRT).
> The same transducer can be used to transmit and receive.
PULSE-ECHO
SPECIMEN
CATHODE-RAY TUBE COUPLANT
TRANSDUCER
DISCONTINUITY
GENERATOR/INDICATOR
INSTRUMENT COAXIAL CABLE
PULSE-ECHO SYSTEM
> Short evenly timed pulses of ultrasonic waves are transmitted into the material being tested.
> These pulses reflect from discontinuities in their path, or from any boundary that they strike.
> The received reflections are then displayed on a cathode ray tube (CRT).
> The same transducer can be used to transmit and receive.
PULSE-ECHO
SPECIMEN
CATHODE-RAY TUBE COUPLANT
TRANSDUCER
DISCONTINUITY
GENERATOR/INDICATOR
INSTRUMENT COAXIAL CABLE
PULSE-ECHO SYSTEM
> Through transmission requires the use of two transducers, one for sending and the other for receiving.
> Either short pulses or continuous waves are transmitted into the material.
RECEIVING
> The quality of the material being tested is measured in terms of energy lost by a sound beam as it travels
TRANSDUCER
SPECIMEN
COUPLANT
THROUGH TRANSMISSION
CATHODE-RAY TUBE
COUPLANT
TRANSMITTING
TRANSDUCER
GENERATOR/INDICATOR
INSTRUMENT COAXIAL CABLE
THROUGH TRANSMISSION SYSTEM
> Either short pulses or continuous waves are transmitted into the material.
RECEIVING
> The quality of the material being tested is measured in terms of energy lost by a sound beam as it travels
TRANSDUCER
SPECIMEN
COUPLANT
THROUGH TRANSMISSION
CATHODE-RAY TUBE
COUPLANT
TRANSMITTING
TRANSDUCER
GENERATOR/INDICATOR
INSTRUMENT COAXIAL CABLE
THROUGH TRANSMISSION SYSTEM
> There are two test methods normally used in ultrasonic testing.
- where the transducer is coupled to the material through a thin layer of couplant.
- both the material and the transducer are immersed in a tank of couplant (usually water).
- where the transducer is coupled to the material through a thin layer of couplant.
- both the material and the transducer are immersed in a tank of couplant (usually water).
> To determine the location of discontinuities within a test part, the CRT horizontal display is divided into
convenient increments such as centimeters, inches, etc.
> Ata given sensitivity (gain) setting, the amplitude of the pip is determined by the strength of the signal
generated by the reflected sound wave.
> Thus, the CRT displays two types of information:
1. Distance (time) of the discontinuity from the transducer
2. Relative magnitude of the reflected energy
> Focus and astigmatism controls - adjust the sharpness of the displayed signals.
> Sensitivity or gain controls - determine the amount of amplification the signals from the discontinuity received.
> Increasing the sensitivity (gain) increases the amplitude of the pips on the CRT screen.
> Two controls, the “Sweep Length (ZERO)" and “Sweep Delay” regulate how much of the test part is displayed at
one time on the CRT, and what portion of the part is displayed.
convenient increments such as centimeters, inches, etc.
> Ata given sensitivity (gain) setting, the amplitude of the pip is determined by the strength of the signal
generated by the reflected sound wave.
> Thus, the CRT displays two types of information:
1. Distance (time) of the discontinuity from the transducer
2. Relative magnitude of the reflected energy
> Focus and astigmatism controls - adjust the sharpness of the displayed signals.
> Sensitivity or gain controls - determine the amount of amplification the signals from the discontinuity received.
> Increasing the sensitivity (gain) increases the amplitude of the pips on the CRT screen.
> Two controls, the “Sweep Length (ZERO)" and “Sweep Delay” regulate how much of the test part is displayed at
one time on the CRT, and what portion of the part is displayed.
> The Sweep Length (ZERO) (material control) expands or compresses the display on the CRT as shown
below:
“a — 1W. KO 40 FT. 4»
| K
| à
EXPANDED SWEEP COMPRESSED SWEEP
VIEW A VIEW 8
below:
“a — 1W. KO 40 FT. 4»
| K
| à
EXPANDED SWEEP COMPRESSED SWEEP
VIEW A VIEW 8
> The Sweep Delay control allows one to move the viewing screen along the depth of the test part.
> In immersion testing, the sweep delay can be used to remove the initial pulse from the CRT.
A - INITIAL PULSE
B - FRONT SURFACE PIP
C - 1ST BACK SURFACE REFLECTION PIP
0
VIEW B
> In immersion testing, the sweep delay can be used to remove the initial pulse from the CRT.
A - INITIAL PULSE
B - FRONT SURFACE PIP
C - 1ST BACK SURFACE REFLECTION PIP
0
VIEW B
> "Pulse repetition rate" control regulates how often the pulse is applied. Pulse rates vary from 50 to 1200
pulses per second or more.
> When the sweep is long, the pulse rate must be lower to allow enough time for the sweep to be displayed
before another pulse is transmitted.
> In some instruments the pulse rate is adjusted automatically.
> Increasing the pulse length increases the amount of sound energy applied to the test part, but decreases
the resolving power of the equipment.
> The "pulse energy" must be increased to obtain deep penetration or to penetrate coarse grained materials.
> The “reject control" or "suppression control” is used to eliminate or reduce "grass" or very low amplitude pips
along the base of the sweep line. This control may affect the vertical linearity of the presentation.
> A “flaw alarm" or “gating circuit" is used to establish zones along the sweep line within which pips of
predetermined amplitude will activate either an alarm or a recording system.
D END OF GATE
VIEWA views
pulses per second or more.
> When the sweep is long, the pulse rate must be lower to allow enough time for the sweep to be displayed
before another pulse is transmitted.
> In some instruments the pulse rate is adjusted automatically.
> Increasing the pulse length increases the amount of sound energy applied to the test part, but decreases
the resolving power of the equipment.
> The "pulse energy" must be increased to obtain deep penetration or to penetrate coarse grained materials.
> The “reject control" or "suppression control” is used to eliminate or reduce "grass" or very low amplitude pips
along the base of the sweep line. This control may affect the vertical linearity of the presentation.
> A “flaw alarm" or “gating circuit" is used to establish zones along the sweep line within which pips of
predetermined amplitude will activate either an alarm or a recording system.
D END OF GATE
VIEWA views
> "Distance/amplitude control" - in ultrasonic testing the amplitude of the pip from a discontinuity of a given size
decreases as the depth increases. To compensate for this "attenuation," an electronic control has been added
to many ultrasonic units.
> Some of the common names for this control are:
> DAC - distance amplitude correction
> TCG - time corrected gain
> STC - sensitivity time control
> This control is very useful when used in conjunction with the flaw alarm and with recording systems.
WITHOUT DAC WITH DAC
decreases as the depth increases. To compensate for this "attenuation," an electronic control has been added
to many ultrasonic units.
> Some of the common names for this control are:
> DAC - distance amplitude correction
> TCG - time corrected gain
> STC - sensitivity time control
> This control is very useful when used in conjunction with the flaw alarm and with recording systems.
WITHOUT DAC WITH DAC
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
WAVE PROPAGATION
REFLECTION € REFRACTION.
METHOD LEVEL Ihé. III
WAVE PROPAGATION
REFLECTION € REFRACTION.
Course Contains
1. Application, Training & Certification.
2. Ultrasonic Principles.
3. Ultrasonic Testing Methods & Equipment Controls.
4. Wave propagation, Retlection & Refraction.
5. Couplant, Ultrasonic Sound Energy & Materials Characteristics
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
1. Application, Training & Certification.
2. Ultrasonic Principles.
3. Ultrasonic Testing Methods & Equipment Controls.
4. Wave propagation, Retlection & Refraction.
5. Couplant, Ultrasonic Sound Energy & Materials Characteristics
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
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> LinkedIn :- Vishal Dhameliya D ULTRASONIC TES
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| ¢
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> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
> YouTube Channel -- WELDING KNOWLEDGE
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> LinkedIn :- Vishal Dhameliya D ULTRASONIC TES
https://www. linkedin.com/in/vishal-dhameliya-07605a4a/ METHOD LEVEL 114
| ¢
"EST eg and NDT Creat Rena
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
2 Modes of ultrasonic wave travel
> Velocity can be defined as the distance a wave will propagate through a medium in a given unit of time, usually a second.
> The wave speed remains constant through a given medium.
> Listed below is a table of impedance, velocity and density values. This information will be useful later in this
Chapter for performing basic ultrasonic calculations.
TRANSDUCER ACOSTIC so
STEEL Y MATERIAL | | IMPEDANCE
N OIL COUPLANT GRAM/CM? - SEC | CM/SEC
POINT A
TS Air 0.000033X10° 0.33X10* 0.001
A APULSES . Water 0.149 X 108 1.49 X 10° 1.00
POINT B ===
Tem Aluminum 1.72 X 10° 6.35 X 10° 2.71
=== Steel 4.56 X 105 5.85 X 105 78
> Velocity can be defined as the distance a wave will propagate through a medium in a given unit of time, usually a second.
> The wave speed remains constant through a given medium.
> Listed below is a table of impedance, velocity and density values. This information will be useful later in this
Chapter for performing basic ultrasonic calculations.
TRANSDUCER ACOSTIC so
STEEL Y MATERIAL | | IMPEDANCE
N OIL COUPLANT GRAM/CM? - SEC | CM/SEC
POINT A
TS Air 0.000033X10° 0.33X10* 0.001
A APULSES . Water 0.149 X 108 1.49 X 10° 1.00
POINT B ===
Tem Aluminum 1.72 X 10° 6.35 X 10° 2.71
=== Steel 4.56 X 105 5.85 X 105 78
> Ultrasonic waves are reflected when they encounter a medium of a different acoustical impedance. The
"surface" at which this reflection occurs is called an "interface."
> An interface is the common boundary between two materials or phases, such as aluminum-to-steel or water-to-steel.
> A beam of energy approaching an interface is referred to as an “incident wave.”
> The angle at which the wave strikes the interface is known as the “angle of incidence" as shown below.
INCIDENT WAVE IMAGINAR
PERPENDICULAR
LINE
INCIDENT WAVE 7?
INTERFACE
Media 1 INTERFACE
>
Media 2 ANGULAR INCIDENCE NORMAL INCIDENCE
"surface" at which this reflection occurs is called an "interface."
> An interface is the common boundary between two materials or phases, such as aluminum-to-steel or water-to-steel.
> A beam of energy approaching an interface is referred to as an “incident wave.”
> The angle at which the wave strikes the interface is known as the “angle of incidence" as shown below.
INCIDENT WAVE IMAGINAR
PERPENDICULAR
LINE
INCIDENT WAVE 7?
INTERFACE
Media 1 INTERFACE
>
Media 2 ANGULAR INCIDENCE NORMAL INCIDENCE
> The incident wave is said to have normal incidence when its direction of propagation is perpendicular to an interface.
> As shown below the angle of incidence is zero.
> Some of the wave energy striking an interface will be transmitted through the interface, and some will be
reflected at the angle of incidence.
> The amount a depends on the Acoustic impedance ratio between the two media involved. This
reflectance factor will be discussed in detail in the next Chapter.
INCIDENT WAVE IMAGINARY
PERPENDICULAR
LINE
INCIDENT WAVE <7?
INTERFACE
Media 1 INTERFACE
>
Media 2 ANGULAR INCIDENCE NORMAL INCIDENCE
> As shown below the angle of incidence is zero.
> Some of the wave energy striking an interface will be transmitted through the interface, and some will be
reflected at the angle of incidence.
> The amount a depends on the Acoustic impedance ratio between the two media involved. This
reflectance factor will be discussed in detail in the next Chapter.
INCIDENT WAVE IMAGINARY
PERPENDICULAR
LINE
INCIDENT WAVE <7?
INTERFACE
Media 1 INTERFACE
>
Media 2 ANGULAR INCIDENCE NORMAL INCIDENCE
> The angle of reflection at an interface or boundary always equals the angle of incidence. Angle “A" = angle “B“
NORMAL
INCIDENCE por
| COUPLANT
are
INCIDENT WAVE —_.\ LA REFLECTED WAVE | INTERFACE OR BA
“a
INTERFACE
/
ANGLE OF REFLECTION IMAGINARY LIKE N
> Ultrasonic vibrations travel in many modes, and the most common are:
1)
2)
3)
4)
> Each wave mode has a specific function in ultrasonic inspection and it is important that each be understood
completely.
NORMAL
INCIDENCE por
| COUPLANT
are
INCIDENT WAVE —_.\ LA REFLECTED WAVE | INTERFACE OR BA
“a
INTERFACE
/
ANGLE OF REFLECTION IMAGINARY LIKE N
> Ultrasonic vibrations travel in many modes, and the most common are:
1)
2)
3)
4)
> Each wave mode has a specific function in ultrasonic inspection and it is important that each be understood
completely.
> Longitudinal (compressional) waves have particle vibrations in a back and forth motion in the direction of wave propagation.
> Consider that all materials are made up of atoms lined up in straight lines to form a lattice structure. When striking the side
of the lattice, a chain reaction of particle movement is started causing the longitudinal wave.(in steel velocity-5920 m/s).
wi
PARTICLE MOTION
LONGITUDINAL WAVES
> Shear (transverse) waves have particle vibrations perpendicular to the direction of wave motion.
> Shear waves will not travel through liquids or gasses.(in steel velocity 3250 m/s)
> In some materials, the velocity of a shear wave is about 1/2 that of longitudinal waves. Therefore, the wavelength is
shorter (about 1/2), permitting smaller discontinuities to be located.
MEDIUM
tan + 4%
= |
or
PARTICLE MOTION
[ A
(SHEAR WAVES)
> Consider that all materials are made up of atoms lined up in straight lines to form a lattice structure. When striking the side
of the lattice, a chain reaction of particle movement is started causing the longitudinal wave.(in steel velocity-5920 m/s).
wi
PARTICLE MOTION
LONGITUDINAL WAVES
> Shear (transverse) waves have particle vibrations perpendicular to the direction of wave motion.
> Shear waves will not travel through liquids or gasses.(in steel velocity 3250 m/s)
> In some materials, the velocity of a shear wave is about 1/2 that of longitudinal waves. Therefore, the wavelength is
shorter (about 1/2), permitting smaller discontinuities to be located.
MEDIUM
tan + 4%
= |
or
PARTICLE MOTION
[ A
(SHEAR WAVES)
> Mode conversion takes place when a sound beam hits an interface between two different media at an angle
other than 90 degrees.
> Mode conversion in the case presented below produces two reflected beams:
> One beam consists of longitudinal waves.
> The other beam consists of shear waves.
Transducer
Refracted Beam
(Longitudinal Wave)
Refracted Beam
(Shear Wave)
other than 90 degrees.
> Mode conversion in the case presented below produces two reflected beams:
> One beam consists of longitudinal waves.
> The other beam consists of shear waves.
Transducer
Refracted Beam
(Longitudinal Wave)
Refracted Beam
(Shear Wave)
> The ultrasonic angle beam transducer uses the following example. The "refracted" shear waves are useful in
many inspection techniques.
> The ee | is the angle formed between a Refracted beam as it enters the second medium and a
line drawn perpendicular to the interface.
NORMAL
INCIDENCE
INCIDENT BEAM
(LONGITUDINAL)
INTERFACE
REFRACTED BEAM
{LONGITUDINAL WAVES)
REFRACTED BEAM (SHEAR WAVES)
ANGLE OF REFRACTION (SHEAR)
many inspection techniques.
> The ee | is the angle formed between a Refracted beam as it enters the second medium and a
line drawn perpendicular to the interface.
NORMAL
INCIDENCE
INCIDENT BEAM
(LONGITUDINAL)
INTERFACE
REFRACTED BEAM
{LONGITUDINAL WAVES)
REFRACTED BEAM (SHEAR WAVES)
ANGLE OF REFRACTION (SHEAR)
a
> Snell's law can be used to determine angular relationships between media for both longitudinal and shear waves.
Q, = ANGLE OF INCIDENCE
SIN Y, _ Vi V, = VELOCITY IN FIRST MEDIUM
SIN Ps Va &: = ANGLE OF REFRACTION
V2 = VELOCITY IN SECOND MEDIUM
> The following example calculates the angle of refraction @2 for a longitudinal wave passing through a water-to-
steel interface.
sin O.
a .
== À
sin 0, V,
Va(sin 0,) |
sin e, = —2___ © |
2 v v
1 FIRST MEDIUM (WATER) 1
V.
she de 1.012 SECOND MEDIUM (STEEL) | 2
2 1.49 |
sin @ = 0.6791 =
|
> Snell's law can be used to determine angular relationships between media for both longitudinal and shear waves.
Q, = ANGLE OF INCIDENCE
SIN Y, _ Vi V, = VELOCITY IN FIRST MEDIUM
SIN Ps Va &: = ANGLE OF REFRACTION
V2 = VELOCITY IN SECOND MEDIUM
> The following example calculates the angle of refraction @2 for a longitudinal wave passing through a water-to-
steel interface.
sin O.
a .
== À
sin 0, V,
Va(sin 0,) |
sin e, = —2___ © |
2 v v
1 FIRST MEDIUM (WATER) 1
V.
she de 1.012 SECOND MEDIUM (STEEL) | 2
2 1.49 |
sin @ = 0.6791 =
|
> As the angle of incidence increases, the angle of refraction increases.
> When the refraction angle of a longitudinal wave reaches 90 degrees, the wave emerges from the second
medium and travels parallel to the interface or surface.
> This is called its first or lower "crit al angle" above approximately 28 degrees with a plastic-to-steel interface,
only shear waves are generated in the part. NORMAL
INCIDENCE,
ANGLE A
INCIDENT BEAM pe
OF INCIDENCE tone wg
PLASTIC REFRACTED INTERFACE
LONGITUDINAL
STEEL | WAVE
90°
| REFRACTED BEAM
| à" (LONGITUDINAL WAVES)
REFRACTED SHEAR
REFRACTED BEAM (SHEAR WAVES)
WAVE ANGLE OF REFRACTION (SHEAR)
> When the refraction angle of a longitudinal wave reaches 90 degrees, the wave emerges from the second
medium and travels parallel to the interface or surface.
> This is called its first or lower "crit al angle" above approximately 28 degrees with a plastic-to-steel interface,
only shear waves are generated in the part. NORMAL
INCIDENCE,
ANGLE A
INCIDENT BEAM pe
OF INCIDENCE tone wg
PLASTIC REFRACTED INTERFACE
LONGITUDINAL
STEEL | WAVE
90°
| REFRACTED BEAM
| à" (LONGITUDINAL WAVES)
REFRACTED SHEAR
REFRACTED BEAM (SHEAR WAVES)
WAVE ANGLE OF REFRACTION (SHEAR)
> If the angle of incidence is increased past the first critical angle, only a shear wave is generated in the part.
When the angle of refraction for the shear wave is 90 degrees, then we have reached the upper or second
critical angle which produces
> As shown below, there is then total reflection for both longitudinal and shear waves.
> With a plastic-to-steel interface, this happens at approximately 58 degrees.
REFLECTED LONGITUDINAL
Æ WAVE
ANGLE
OF INCIDENCE
PLASTIC
REFRACTED SHEAR
Wave (SURFACE WAVE)
> When the incident beam is at its SBeondicriticallangle, a third type of wave is developed, called a Rayleigh or
(1) Longitudinal (compression) (2) Shear (transverse) (3) Surface (Rayleigh) (4) Plate (lamb)
When the angle of refraction for the shear wave is 90 degrees, then we have reached the upper or second
critical angle which produces
> As shown below, there is then total reflection for both longitudinal and shear waves.
> With a plastic-to-steel interface, this happens at approximately 58 degrees.
REFLECTED LONGITUDINAL
Æ WAVE
ANGLE
OF INCIDENCE
PLASTIC
REFRACTED SHEAR
Wave (SURFACE WAVE)
> When the incident beam is at its SBeondicriticallangle, a third type of wave is developed, called a Rayleigh or
(1) Longitudinal (compression) (2) Shear (transverse) (3) Surface (Rayleigh) (4) Plate (lamb)
> As shown below, the wave travels with an elliptical particle motion
> Surface waves are useful in detecting surface cracks, but only penetrate about one wavelength.
PARTICLE
rd
PARTICLE MOTION
MEDIUM'S SURFACE
SURFACE WAVES
> As shown below, surface waves have the ability to follow the surface contour as long as the contour does not
sharply change. However, the surface wave can be almost completely absorbed by excess couplant or by
touching your finger to the surface of the part ahead of the transducer.
TRANSDUCER DISCONTINUIT Y
TEST SPECIMEN
> Surface waves are useful in detecting surface cracks, but only penetrate about one wavelength.
PARTICLE
rd
PARTICLE MOTION
MEDIUM'S SURFACE
SURFACE WAVES
> As shown below, surface waves have the ability to follow the surface contour as long as the contour does not
sharply change. However, the surface wave can be almost completely absorbed by excess couplant or by
touching your finger to the surface of the part ahead of the transducer.
TRANSDUCER DISCONTINUIT Y
TEST SPECIMEN
> Plate waves or lamb waves or Dispersive waves have the ability to propagate through thin plates in a variety of
wave modes depending on plate thickness, transducer frequency and incident angle.
> Plate waves are generated by using longitudinal waves which develop either symmetrical or asymmetrical waves as
shown.
> Plate waves occupy the entire thickness of the part. Without "saturating" the part, the wave cannot exist.
THIN SHEET OR PLATE THIN SHEET OR PLATE
Se
PAGATION
¡DIRECTION OF PRO G
PARTICLE J
SYMMETRICAL ASYMMETRICAL
PLATE WAVES
wave modes depending on plate thickness, transducer frequency and incident angle.
> Plate waves are generated by using longitudinal waves which develop either symmetrical or asymmetrical waves as
shown.
> Plate waves occupy the entire thickness of the part. Without "saturating" the part, the wave cannot exist.
THIN SHEET OR PLATE THIN SHEET OR PLATE
Se
PAGATION
¡DIRECTION OF PRO G
PARTICLE J
SYMMETRICAL ASYMMETRICAL
PLATE WAVES
> To generate plate waves, you adjust the incident angle to the point that maximum reflections are observed on
the CRT screen from a known reflector.
> It is not possible to generate shear or surface waves on materials thinner than one-half wavelength. Therefore,
plate waves are useful as shown below.
TRANSDUCER
HOLLOW EXTRUSION
the CRT screen from a known reflector.
> It is not possible to generate shear or surface waves on materials thinner than one-half wavelength. Therefore,
plate waves are useful as shown below.
TRANSDUCER
HOLLOW EXTRUSION
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
COUPLANT , ULTRASONIC SOUND ENERGY
& MATERIALS CHARACTERISTICS
METHOD LEVEL Ihé. III
COUPLANT , ULTRASONIC SOUND ENERGY
& MATERIALS CHARACTERISTICS
Course Contains
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
Bowne
. Wave propagation, Reflection & Refraction.
5. Couplant, Ultrasonic Sound Energy & Materials Characteristics
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8, Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
Bowne
. Wave propagation, Reflection & Refraction.
5. Couplant, Ultrasonic Sound Energy & Materials Characteristics
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8, Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya ULTRASONIC TESTING
https://www.linkedin.com/in/vishal-dhameliya-07605a4a/ METHOD LEVEL II 4 II
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya ULTRASONIC TESTING
https://www.linkedin.com/in/vishal-dhameliya-07605a4a/ METHOD LEVEL II 4 II
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
> The primary purpose of a couplant is to provide a suitable sound path between the transducer and the test
surface.
> Acouplant must effectively wet or totally contact both surfaces of the transducer and test part.
Couplant should have below properties....
1.The couplant must remove all air from between the surfaces as air is a very poor conductor of sound.
2. The couplant fills in and smooths out irregularities on the surface of the test part.
3. The couplant help in the movement of the transducer over the surface in contact testing.
4. A practical couplant must be easy to apply and easy to remove. It must also be harmless to the part surface.
Transducer/Probe
Couplant
Couplant
Speciman/
Object/job
surface.
> Acouplant must effectively wet or totally contact both surfaces of the transducer and test part.
Couplant should have below properties....
1.The couplant must remove all air from between the surfaces as air is a very poor conductor of sound.
2. The couplant fills in and smooths out irregularities on the surface of the test part.
3. The couplant help in the movement of the transducer over the surface in contact testing.
4. A practical couplant must be easy to apply and easy to remove. It must also be harmless to the part surface.
Transducer/Probe
Couplant
Couplant
Speciman/
Object/job
> Oil or water mixed with glycerine (2 parts water and 1 part glycerine) are commonly used couplants. Even
wallpaper paste has advantages as a couplant.
> Heavier couplants, such as grease or heavy oil can be used on rough or vertical surfaces.
> Specially formulated liquid and paste couplants are also available from ultrasonic equipment manufacturers.
> In circumstances where the use of liquids or paste is undesirable, thin rubber or rubber-like materials may be
used.
> In all cases the couplant should be as thin as possible. If the couplant is excessive, it may act as a wedge and
alter the direction of the sound beam.
Transducer/Probe
Couplant
Speciman/
Object/job
wallpaper paste has advantages as a couplant.
> Heavier couplants, such as grease or heavy oil can be used on rough or vertical surfaces.
> Specially formulated liquid and paste couplants are also available from ultrasonic equipment manufacturers.
> In circumstances where the use of liquids or paste is undesirable, thin rubber or rubber-like materials may be
used.
> In all cases the couplant should be as thin as possible. If the couplant is excessive, it may act as a wedge and
alter the direction of the sound beam.
Transducer/Probe
Couplant
Speciman/
Object/job
> The surface of a test specimen can greatly affect ultrasonic wave propagation.
> Rough surfaces can cause undesirable effects such as reduction of discontinuity and back surface amplitudes due
to distortion of wave directivity.
Flat Smooth Surface Uneven but Consistant Rough and Irregular
Surface Surface
BEST FAIR POOR
> Rough surfaces can cause undesirable effects such as reduction of discontinuity and back surface amplitudes due
to distortion of wave directivity.
Flat Smooth Surface Uneven but Consistant Rough and Irregular
Surface Surface
BEST FAIR POOR
> A good back surface reflection indicates a good response from the material being tested. It is reflected back to
its source similar to light striking a mirror.
> If the surfaces are not parallel, the reflected energy will be directed away from the transducer similar to light
falling on a mirror at an angle.
TRANSDUCER FRONT SURFACE
FRONT SURFACE A, (INITIAL PULSE) REDUCED
\ BACK SURFACE
1 INDICATION
SPECIMEN
CROSS-SECTION
REFLECTION
BACK SURFAC CRT INDICATIONS
o
its source similar to light striking a mirror.
> If the surfaces are not parallel, the reflected energy will be directed away from the transducer similar to light
falling on a mirror at an angle.
TRANSDUCER FRONT SURFACE
FRONT SURFACE A, (INITIAL PULSE) REDUCED
\ BACK SURFACE
1 INDICATION
SPECIMEN
CROSS-SECTION
REFLECTION
BACK SURFAC CRT INDICATIONS
o
> The physical shape or contour of a part must be considered when attempting to discern whether a discontinuity
indication is real or false.
EXAMPLES OF SOUND PATHS LEADING TO SPURIOUS INDICATIONS
indication is real or false.
EXAMPLES OF SOUND PATHS LEADING TO SPURIOUS INDICATIONS
> In testing long specimens, reflection of a spreading beam can produce false indications on the CRT as shown
below.
> A shear wave may be generated which is reflected at a steep angle to the opposite side, where mode
conversion takes place. Mode conversion Already discussed in a Chapter-4. However, this type of false signal
will appear on the right side of the first back echo.
FIRST BACK
LONGITUDINAL WAVE SHEAR WAV! | al WAVE \
| 7
TRANSDUCER Y
N SPECIMEN
A DIAMETER
7 le
below.
> A shear wave may be generated which is reflected at a steep angle to the opposite side, where mode
conversion takes place. Mode conversion Already discussed in a Chapter-4. However, this type of false signal
will appear on the right side of the first back echo.
FIRST BACK
LONGITUDINAL WAVE SHEAR WAV! | al WAVE \
| 7
TRANSDUCER Y
N SPECIMEN
A DIAMETER
7 le
> Grain structure has a great influence on the acoustical properties of a material.
> Asteel forging generally has a fine grain structure and has a low damping effect on the sound beam.
> However, a casting generally has a coarser grain structure which is more difficult to get sound through.
DISCONTINUITY
FRONT SURFACE FRONT SURFACE
BACK SURFACE
\ BACK SURFACE ne REFLECTION
REFLECTION LOST OR REDUCED
FINE GRAIN COARSE GRAIN
> Asteel forging generally has a fine grain structure and has a low damping effect on the sound beam.
> However, a casting generally has a coarser grain structure which is more difficult to get sound through.
DISCONTINUITY
FRONT SURFACE FRONT SURFACE
BACK SURFACE
\ BACK SURFACE ne REFLECTION
REFLECTION LOST OR REDUCED
FINE GRAIN COARSE GRAIN
> When a discontinuity is not normal (at 90 degrees) to the incident wave, the reflected wave will be at an angle.
> As shown below, the result is a reduction in the amplitude of the discontinuity indication displayed on the CRT.
> At position “A" above, there is a sharp discontinuity indication and little back surface indication. At position “C"
the discontinuity is at a minimum, or may not be seen at all.
POSITION €
POSITION B
CRACK
POSITION A CYLINDRICAL SPECIMEN
POSITION A POSITION B POSITION C
> As shown below, the result is a reduction in the amplitude of the discontinuity indication displayed on the CRT.
> At position “A" above, there is a sharp discontinuity indication and little back surface indication. At position “C"
the discontinuity is at a minimum, or may not be seen at all.
POSITION €
POSITION B
CRACK
POSITION A CYLINDRICAL SPECIMEN
POSITION A POSITION B POSITION C
> Two basic techniques are used in locating and evaluating angular flaws.
1. Contact testing utilizes an "angle beam" transducer with a plastic wedge to change the direction of
wave propagation.
2. Immersion testing uses water as a couplant, tilting the transducer to achieve the necessary
directionality
ANGLE BEAM TRANSDUCER
TRANSDUCER
\ PLASTIC WEDGE WATER
SPECIMEN TANK
SPECIMEN
CONTACT TESTING IMMERSION TESTING
> The shape or surface condition of a discontinuity influences the indication on the CRT.
> A discontinuity having a rough surface will tend to scatter the reflection as compared to a smooth flaw.
> Nonmetallic inclusions are typically rough and would scatter the sound more than a crack-like discontinuity.
1. Contact testing utilizes an "angle beam" transducer with a plastic wedge to change the direction of
wave propagation.
2. Immersion testing uses water as a couplant, tilting the transducer to achieve the necessary
directionality
ANGLE BEAM TRANSDUCER
TRANSDUCER
\ PLASTIC WEDGE WATER
SPECIMEN TANK
SPECIMEN
CONTACT TESTING IMMERSION TESTING
> The shape or surface condition of a discontinuity influences the indication on the CRT.
> A discontinuity having a rough surface will tend to scatter the reflection as compared to a smooth flaw.
> Nonmetallic inclusions are typically rough and would scatter the sound more than a crack-like discontinuity.
> or transferring ultrasonic vibrations into liquids or solids. Therefore, a couplant must be
used to transfer energy from the transducer to the test material.
> Wateris «common used coupant a shawn below:
| SECONDARY LOBES
TRANSDUCER /d
WATER
PRINCIPAL DIRECTION
OF SOUND BEAM
SECONDARY LOBES
> Most of the ultrasonic energy is concentrated along the centerline of the beam.
> The secondary or side lobes form at the transducer face and radiate away from the principle direction of sound
travel.
> These secondary lobes represent areas of high and low intensities at the edge of the beam.
> Because of the secondary lobes, the useful width of a transducer beam is less than the transducer's physical width.
> Transducer diameter has a definite influence on the sound beam transmitted through a medium.
> For a given frequency, a smaller transducer has a greater beam Spread angle than a larger diameter transducer
as shown below:
used to transfer energy from the transducer to the test material.
> Wateris «common used coupant a shawn below:
| SECONDARY LOBES
TRANSDUCER /d
WATER
PRINCIPAL DIRECTION
OF SOUND BEAM
SECONDARY LOBES
> Most of the ultrasonic energy is concentrated along the centerline of the beam.
> The secondary or side lobes form at the transducer face and radiate away from the principle direction of sound
travel.
> These secondary lobes represent areas of high and low intensities at the edge of the beam.
> Because of the secondary lobes, the useful width of a transducer beam is less than the transducer's physical width.
> Transducer diameter has a definite influence on the sound beam transmitted through a medium.
> For a given frequency, a smaller transducer has a greater beam Spread angle than a larger diameter transducer
as shown below:
SMALL DIAMETER MEDIUM LARGE DIAMETER
TRANSDUCER ya TRANSDUCER A
===
| aw |
AN —
> Changing the transducer's vibrating frequency will also change the beam spread.
MEDIUM
> Divergence is inversely proportional to frequency.
> Therefore, a high frequency transducer has a more constant diameter sound beam than a low frequency
transducer.
> Beam divergence can be reduced by increasing the transducer frequency or by using a larger diameter
transducer,
TRANSDUCER ya TRANSDUCER A
===
| aw |
AN —
> Changing the transducer's vibrating frequency will also change the beam spread.
MEDIUM
> Divergence is inversely proportional to frequency.
> Therefore, a high frequency transducer has a more constant diameter sound beam than a low frequency
transducer.
> Beam divergence can be reduced by increasing the transducer frequency or by using a larger diameter
transducer,
A
D
SIN@ = 1.22
WHERE A= WAVELENGTH
D= DIAMETER
@= HALF-ANGLE OF
BEAM. READ TO
. HALF- ER POINTS
N
THE BEAM SPREAD OF A 1/2 INCH
DIAMETER, 1 MHz) TRANSDUCER 1S
SHOWN TO BE 34 DEGREES.
REMEMBER THAT WAVELENGTH ( À )
IS DETERMINED BY DIVIDING THE
VELOCITY BY THE FREQUENCY.
TO CHANGE INCHES TO CENTIMETERS,
MULTIPLY BY 2.54.
D
SIN@ = 1.22
WHERE A= WAVELENGTH
D= DIAMETER
@= HALF-ANGLE OF
BEAM. READ TO
. HALF- ER POINTS
N
THE BEAM SPREAD OF A 1/2 INCH
DIAMETER, 1 MHz) TRANSDUCER 1S
SHOWN TO BE 34 DEGREES.
REMEMBER THAT WAVELENGTH ( À )
IS DETERMINED BY DIVIDING THE
VELOCITY BY THE FREQUENCY.
TO CHANGE INCHES TO CENTIMETERS,
MULTIPLY BY 2.54.
pa ee
A ——
Jewavelength
D= Diameter, oF THIS CL can
elect] in Carbon sted = 9820 Ms
Transducer
cy OF
le. oF Beam sprea to half Pet.
x side
> coatlane
\
d= 10, F=4mn2, 0" Al = E
F 4x oF
@d:24, p=4 mie, 0:43 $
@ d= 10 F=2 miz, 9-11 Simo=1:22 2 3
Comclusi @):2 1 >
21 Sie 224, F= 2 MHZ, 0=86 2122 xt48 =
10 Pole:
V\ SKILL INDIA MOVEMENT = 018056. x
y
Di Ot
FL OT Explain by Vishal Dona] [Ones es)
A ——
Jewavelength
D= Diameter, oF THIS CL can
elect] in Carbon sted = 9820 Ms
Transducer
cy OF
le. oF Beam sprea to half Pet.
x side
> coatlane
\
d= 10, F=4mn2, 0" Al = E
F 4x oF
@d:24, p=4 mie, 0:43 $
@ d= 10 F=2 miz, 9-11 Simo=1:22 2 3
Comclusi @):2 1 >
21 Sie 224, F= 2 MHZ, 0=86 2122 xt48 =
10 Pole:
V\ SKILL INDIA MOVEMENT = 018056. x
y
Di Ot
FL OT Explain by Vishal Dona] [Ones es)
aoa»
Dos»
ret eo (
Fi © À
Fo NR
FG NY
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ret eo (
Fi © À
Fo NR
FG NY
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
ATTENUATION, ACOUSTIC
IMPEDANCE, AND RESONANCE.
METHOD LEVEL Ihé. III
ATTENUATION, ACOUSTIC
IMPEDANCE, AND RESONANCE.
Course Contains
Application, Training & Certification.
Ultrasonic Principles.
Ultrasonic Testing Methods & Equipment Controls.
Wave propagation, Reflection & Refraction.
Bak ete Le te dy
Couplant , Ultrasonic Sound Energy & Materials Characteristics
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
Application, Training & Certification.
Ultrasonic Principles.
Ultrasonic Testing Methods & Equipment Controls.
Wave propagation, Reflection & Refraction.
Bak ete Le te dy
Couplant , Ultrasonic Sound Energy & Materials Characteristics
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES UAT GUJARAT
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
SERVICES
> LinkedIn :- Vishal Dhameliya ULTRASONIC TESTING
https: //www.linkedin.com/in/vishal-dhameliya-07605a4a/] METHOD LEVEL II &
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
SERVICES
> LinkedIn :- Vishal Dhameliya ULTRASONIC TESTING
https: //www.linkedin.com/in/vishal-dhameliya-07605a4a/] METHOD LEVEL II &
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
>
> Attenuation, acoustic impedance, and resonance
> As shown below, a beam of sound energy will spread out (diverge) as it moves through the specimen, and the
intensity (energy) decreases with distance away from the transducer and away from the center of the beam.
sPECME
HEAR ZONE
TRANSDUCER
Piezoelectric Element
Near Field | Far Field
> Attenuation, acoustic impedance, and resonance
> As shown below, a beam of sound energy will spread out (diverge) as it moves through the specimen, and the
intensity (energy) decreases with distance away from the transducer and away from the center of the beam.
sPECME
HEAR ZONE
TRANSDUCER
Piezoelectric Element
Near Field | Far Field
Specimen/job/object
(Material)
Transducer Transducer
(Transmitter) Receiver)
Near Zone Far Zone
Q For a given size transducer:
> High frequency transducers produce narrower sound beams than low frequency transducers, So low frequency
then beam spread higher and higher frequency beam spread low.
> For the purpose of illustration, ultrasonic sound can be viewed as a narrow cone-shaped beam which is divided
into two zones.
> The intensity in the near zone varies irregularly due to sound wave interaction close to the transducer.
> This prevents reliable detection of discontinuities close to the surface.
> In the Far zone, the intensity (Energy) decreases steadily due to both attenuation and beam spread.
> The intensity at point “Y" above is less than at point “X". Attenuation is the term used to describe this condition
of energy loss. Attenuation means the process of lessening the amount.
> The primary reasons for Attenuation are absorption and scattering of the ultrasonic energy.
(Material)
Transducer Transducer
(Transmitter) Receiver)
Near Zone Far Zone
Q For a given size transducer:
> High frequency transducers produce narrower sound beams than low frequency transducers, So low frequency
then beam spread higher and higher frequency beam spread low.
> For the purpose of illustration, ultrasonic sound can be viewed as a narrow cone-shaped beam which is divided
into two zones.
> The intensity in the near zone varies irregularly due to sound wave interaction close to the transducer.
> This prevents reliable detection of discontinuities close to the surface.
> In the Far zone, the intensity (Energy) decreases steadily due to both attenuation and beam spread.
> The intensity at point “Y" above is less than at point “X". Attenuation is the term used to describe this condition
of energy loss. Attenuation means the process of lessening the amount.
> The primary reasons for Attenuation are absorption and scattering of the ultrasonic energy.
ve en gt }
.prequenc) Ss
ys Mo: in steel Velo)
mis
(Gaze re
D =diamerr 0€ P
N = Near Zone
Angle oF Be ¡ADA
example _ Answa —>& anne !
4 mhz —O=10. 36 & N=
D9=24 wm Es 4 mhz 7 97 =430 FN
[ICH 21-47 LN= ¿as mlot op [rt 0?
© D= lo mm , F= 9 Mtz =>
@D-24 mm,F=2 MHA 0= 3.28 LN = 48m apor] AL NL
87 Vishal Dhamelida
Far Zone ‚Ver.
u
Solve Below
© D=lo mm, F=
.prequenc) Ss
ys Mo: in steel Velo)
mis
(Gaze re
D =diamerr 0€ P
N = Near Zone
Angle oF Be ¡ADA
example _ Answa —>& anne !
4 mhz —O=10. 36 & N=
D9=24 wm Es 4 mhz 7 97 =430 FN
[ICH 21-47 LN= ¿as mlot op [rt 0?
© D= lo mm , F= 9 Mtz =>
@D-24 mm,F=2 MHA 0= 3.28 LN = 48m apor] AL NL
87 Vishal Dhamelida
Far Zone ‚Ver.
u
Solve Below
© D=lo mm, F=
> Attenuation is different in different materials, depending on the absorption and scattering of the sound energy.
Another phenomenon which pertains to the interrelationship of the sound and material properties is "acoustic
impedance." This term should not be confused with "attenuation."
> "Acoustical impedance" (Z) is defined as the product of the density 9 and sound velocity (V) within a given material.
> Impedance = density x velocity, or Z= 9 V
> Impedance values for typical materials are shown below:
Air 0.000033 X 10% 0.33 X 10* 0.001
Water 0.149 X 10% 1.49 X 105 1.00
Aluminum 1,72 X 10° 6.35 X 10° aa
Steel 4.56 X 10% 5.85 X 10° 7.8
Another phenomenon which pertains to the interrelationship of the sound and material properties is "acoustic
impedance." This term should not be confused with "attenuation."
> "Acoustical impedance" (Z) is defined as the product of the density 9 and sound velocity (V) within a given material.
> Impedance = density x velocity, or Z= 9 V
> Impedance values for typical materials are shown below:
Air 0.000033 X 10% 0.33 X 10* 0.001
Water 0.149 X 10% 1.49 X 105 1.00
Aluminum 1,72 X 10° 6.35 X 10° aa
Steel 4.56 X 10% 5.85 X 10° 7.8
> Attenuation is defined as the loss of energy (acoustic) per unit of distance. For ultrasonic wave propagation, the
attenuation constant a is given by:
I .
a e -2q Where q =Atténuation Constant
Ih
2 = Ratio of Intensities at two points.a unit distance apart
> If acoustic energy is transmitted into two pieces of perfectly bonded identical steel, we find the sound has the
same velocity through both, with an impedance ratio of 1 to 1. Impedance = density x velocity, or Z= 9 V
a ST
VELOCITY REMAINS CONSTANT
TRANSDUCER
attenuation constant a is given by:
I .
a e -2q Where q =Atténuation Constant
Ih
2 = Ratio of Intensities at two points.a unit distance apart
> If acoustic energy is transmitted into two pieces of perfectly bonded identical steel, we find the sound has the
same velocity through both, with an impedance ratio of 1 to 1. Impedance = density x velocity, or Z= 9 V
a ST
VELOCITY REMAINS CONSTANT
TRANSDUCER
> An impedance ratio of anything less or greater than 1 to 1 is less than ideal.
> As shown below a large portion of the sound beam from a water to steel interface will reflect back towards the
transducer and never enter the part.
TRANSBUCER WATER
SOUND BEAM
> To determine how much of the energy is reflected you can use the following formula:
Z}-22
£1+22
> In the illustration above, how much of the sound energy is reflected from the water to steel interface?
REFLECTION FACTOR (R) =
> Z= acoustical impedance
> As shown below a large portion of the sound beam from a water to steel interface will reflect back towards the
transducer and never enter the part.
TRANSBUCER WATER
SOUND BEAM
> To determine how much of the energy is reflected you can use the following formula:
Z}-22
£1+22
> In the illustration above, how much of the sound energy is reflected from the water to steel interface?
REFLECTION FACTOR (R) =
> Z= acoustical impedance
MATERIALS IMPEDANCE DENSITY
GRAM/CM? = SEC GRAM/CM?
Air 0.000033 X 10° 0.33 X 10° 0.001
Water 0.149 X 10% 1.49 X 105 1.00
Aluminum 1.727% 10° 6.35 X 10° Wee
Steel 4.56 X 10% 5.85 X 10° 7.8
gi-z2\2
> Z= accustied mpedanee REFLECTION FACTOR (R) = ( 22)
> In the illustration above, how much of the sound energy is reflected from the water to steel interface?
sc)
2
— = 0,
4.5640.149 ) =88 % percent Reflected
Reflection Factor (R) = ( (=
GRAM/CM? = SEC GRAM/CM?
Air 0.000033 X 10° 0.33 X 10° 0.001
Water 0.149 X 10% 1.49 X 105 1.00
Aluminum 1.727% 10° 6.35 X 10° Wee
Steel 4.56 X 10% 5.85 X 10° 7.8
gi-z2\2
> Z= accustied mpedanee REFLECTION FACTOR (R) = ( 22)
> In the illustration above, how much of the sound energy is reflected from the water to steel interface?
sc)
2
— = 0,
4.5640.149 ) =88 % percent Reflected
Reflection Factor (R) = ( (=
> Resonance can be defined as the characteristic of a vibrating body to resonate or vibrate in sympathy with a
vibration source.
> As shown below, a resonant condition will exist any time a continuous longitudinal wave is introduced into a
specimen and reflected "in phase" with the incoming wave.
rmanspucen— > STANDING WAVES
— À
> Resonance will occur only when the thickness of a specimen is equal to a half-wavelength or an exact multiple of
a half-wave-length. Shown below is a "fundamental frequency" and multiples called "harmonics."
TEST SPECIMEN REFLECTED WAVE
TRANSOUGER WN
a INCIDENT WAVE
MHz
(FUNDAMENTAL FREQUENCY)
MHz
GND HARMONIC)
MHz
BAD AARMONIC)
LU sucuness = 2-12 waveceucrus ——]
vibration source.
> As shown below, a resonant condition will exist any time a continuous longitudinal wave is introduced into a
specimen and reflected "in phase" with the incoming wave.
rmanspucen— > STANDING WAVES
— À
> Resonance will occur only when the thickness of a specimen is equal to a half-wavelength or an exact multiple of
a half-wave-length. Shown below is a "fundamental frequency" and multiples called "harmonics."
TEST SPECIMEN REFLECTED WAVE
TRANSOUGER WN
a INCIDENT WAVE
MHz
(FUNDAMENTAL FREQUENCY)
MHz
GND HARMONIC)
MHz
BAD AARMONIC)
LU sucuness = 2-12 waveceucrus ——]
> Ultrasonic units using the principle of resonance were commonly used for thickness measurement and bond or
lamination inspection.
> However, pulse-echo units have been refined to perform most of these functions and resonant instruments are
rarely used.
> Resonance occurs when the material thickness is equal to a half-wavelength or exact multiples.
> The wavelength can be changed by varying the frequency.
> The fundamental resonant frequency is the lowest frequency at which a specimen will resonate.
> Harmonics are exact multiples of the fundamental (minimum) resonant frequency. The fundamental resonant
frequency can be found by: V
F= Fundamental Resonant Frequency F = —
V= Velocity of Longitudinal Wave
T= Thickness of Material 2 5
remar rransoucer 3 bisconTinuity
orar —{ >
> As shown above in “A", the frequency has been adjusted until a standing wave "resonance" has been established.
> If the transducer is moved to position “B", the material will stop resonating until the frequency (wavelength) is
adjusted to again establish resonance as shown.
lamination inspection.
> However, pulse-echo units have been refined to perform most of these functions and resonant instruments are
rarely used.
> Resonance occurs when the material thickness is equal to a half-wavelength or exact multiples.
> The wavelength can be changed by varying the frequency.
> The fundamental resonant frequency is the lowest frequency at which a specimen will resonate.
> Harmonics are exact multiples of the fundamental (minimum) resonant frequency. The fundamental resonant
frequency can be found by: V
F= Fundamental Resonant Frequency F = —
V= Velocity of Longitudinal Wave
T= Thickness of Material 2 5
remar rransoucer 3 bisconTinuity
orar —{ >
> As shown above in “A", the frequency has been adjusted until a standing wave "resonance" has been established.
> If the transducer is moved to position “B", the material will stop resonating until the frequency (wavelength) is
adjusted to again establish resonance as shown.
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
DISPLAYING ULTRASONIC INDICATIONS &
ANGLE BEAM INSPECTION WITH CALCULATION
METHOD LEVEL Ihé. III
DISPLAYING ULTRASONIC INDICATIONS &
ANGLE BEAM INSPECTION WITH CALCULATION
Course Contains
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Ultrasonic Transducers And Standard Reference Blocks.
po ON DAH PF Wr PB
|. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell's Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Ultrasonic Transducers And Standard Reference Blocks.
po ON DAH PF Wr PB
|. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell's Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya
https://www. linkedin.com/in/vishal-dhameliya-07605a4a/|
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya
https://www. linkedin.com/in/vishal-dhameliya-07605a4a/|
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
Me
$ Chapter 7:- Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
> Displaying ultrasonic indications
> There are three basic types of visual displays which are commonly used to evaluate the soundness or quality of a
material being tested; A-scan, B-scan and C-scan.
> A-scan is a "time versus amplitude" display which reveals a discontinuity using a "pip" on a cathode-ray tube
(ert).
REFLECTION
AMPLITUDE
DISCONTINUITY
HORIZONTAL SWEEP
$ Chapter 7:- Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
> Displaying ultrasonic indications
> There are three basic types of visual displays which are commonly used to evaluate the soundness or quality of a
material being tested; A-scan, B-scan and C-scan.
> A-scan is a "time versus amplitude" display which reveals a discontinuity using a "pip" on a cathode-ray tube
(ert).
REFLECTION
AMPLITUDE
DISCONTINUITY
HORIZONTAL SWEEP
of a pip can be compared to the height of a pip
A-SCAN PRESENTATION
AMPLITUDE
HORIZONTAL SWEEP
| INITIAL PULSE = DISCONTINUITY BACK SURFACE
TRANSDUCER INDICATION REFLECTION
DISCONTINUITY => [52]
A-SCAN PRESENTATION
AMPLITUDE
HORIZONTAL SWEEP
| INITIAL PULSE = DISCONTINUITY BACK SURFACE
TRANSDUCER INDICATION REFLECTION
DISCONTINUITY => [52]
B-SCAN presentation, as shown below, typically uses an oscilloscope screen to display a cross:
tested.
ctional view of the material being
The image is retained on the CRT long enough to evaluate the sample and.to photograph the screen for a permanent record.
DISCONTINUITIES.
THICKNESS OF
TEST MATERIAL
oN |
As shown below, the c-scan shows the shape and location of the discontinuity, but does not show tl
DISCONTINUITIES
BACK SURFACE
CAN PRESENTATION
C-SCAN PRESENTATION
tested.
ctional view of the material being
The image is retained on the CRT long enough to evaluate the sample and.to photograph the screen for a permanent record.
DISCONTINUITIES.
THICKNESS OF
TEST MATERIAL
oN |
As shown below, the c-scan shows the shape and location of the discontinuity, but does not show tl
DISCONTINUITIES
BACK SURFACE
CAN PRESENTATION
C-SCAN PRESENTATION
> High speed ultrasonic scanning generally utilizes the c-scan presentation.
> As shown below, some recorders use a chemically treated paper. The paper movement is synchronized with the
movement of the transducer across the test surface.
RECORDING PAPER FEED
i
MOTION OF
TRANSDUCER
La TRS a
ll TINUIT DI TI TY
SN À DISCONTINUITY SCONTINUI
HELIX DRUM
> As shown below, some recorders use a chemically treated paper. The paper movement is synchronized with the
movement of the transducer across the test surface.
RECORDING PAPER FEED
i
MOTION OF
TRANSDUCER
La TRS a
ll TINUIT DI TI TY
SN À DISCONTINUITY SCONTINUI
HELIX DRUM
> The advantage of the c-scan is its speed and ability to produce a permanent record. However, the scan shows
only length and width, but not depth. — —
A-SCAN TEST EQUIPMENT
CARRIAGE OR BRIDGE
MANIPULATOR
RECORDER CONTROL PANEL
IMMERSION TANK
CARRIAGE CONTROL PANEL
C-SCAN RECORDER
only length and width, but not depth. — —
A-SCAN TEST EQUIPMENT
CARRIAGE OR BRIDGE
MANIPULATOR
RECORDER CONTROL PANEL
IMMERSION TANK
CARRIAGE CONTROL PANEL
C-SCAN RECORDER
> Atypical bridge/manipulator is shown for a basic ultrasonic immersion test.
> When a c-scan is to be made, electric motors are utilized to activate the traveling mechanisms and the up and
down movement of the search tube.
TANK WITH MOTORIZED BRIDGE
MANIPULATOR
TRANSDUCER
CARRIAGE OR
BRIDGE
TEST SPECIMEN
SUPPORT FOR TEST SPECIMEN
> When a c-scan is to be made, electric motors are utilized to activate the traveling mechanisms and the up and
down movement of the search tube.
TANK WITH MOTORIZED BRIDGE
MANIPULATOR
TRANSDUCER
CARRIAGE OR
BRIDGE
TEST SPECIMEN
SUPPORT FOR TEST SPECIMEN
> A typical A-Scan presentation is shown below using contact testing with an angle beam transducer.
> The procedure used to calibrate the UT unit is similar to normal beam testing and requires a calibration block
with a known size reflection surface at a known metal travel.
ANGLE BEAM TRANSDUCER
SHEAR
CRT WAVES
> The procedure used to calibrate the UT unit is similar to normal beam testing and requires a calibration block
with a known size reflection surface at a known metal travel.
ANGLE BEAM TRANSDUCER
SHEAR
CRT WAVES
> A calibration block (IIW test block further discussed in lesson 8) is shown below with a known distance of 4 inches
to the curved surface.
> Using the sweep and delay controls, the pips are adjusted to show multiples of 4 inches on the crt.
| |
Oo SR Rp
o
o 2 4 6 8 10
> If the minature angle beam calibration block shown below were used to calibrate the above crt screen, where
would the pips appear? Aa
MINIATURE ANGLE BEAM
> Depending on the direction of the angle beam probe, the pips would either appear at one, four, and seven inches
or two, five, and eight inches.
to the curved surface.
> Using the sweep and delay controls, the pips are adjusted to show multiples of 4 inches on the crt.
| |
Oo SR Rp
o
o 2 4 6 8 10
> If the minature angle beam calibration block shown below were used to calibrate the above crt screen, where
would the pips appear? Aa
MINIATURE ANGLE BEAM
> Depending on the direction of the angle beam probe, the pips would either appear at one, four, and seven inches
or two, five, and eight inches.
> The angle beam technique is often used for weld inspection as shown below.
2nd LEG y 4th LEG .
\
D
'
Ist, LEG 3rd LEG
‘ ı
E ist skip distance — _ 2nd skip distance—,
CV" PATH) CV" PATH)
> Typically, the weld should be inspected in the 1st or 2nd leg when-ever possible as shown below.
SKIP.
DISTANCE
2nd LEG y 4th LEG .
\
D
'
Ist, LEG 3rd LEG
‘ ı
E ist skip distance — _ 2nd skip distance—,
CV" PATH) CV" PATH)
> Typically, the weld should be inspected in the 1st or 2nd leg when-ever possible as shown below.
SKIP.
DISTANCE
> To assist in evaluating the results of angle beam inspection, a direct reading ultrasonic calculator is commonly used.
>The horizontal scale across the top of the card represents the number of inches between the transducer and the
center of the weld.
> The vertical scale represents specimen thickness and the arc shows the angle of the sound beam.
> The following is an example of a typical angle beam inspection using the ultrasonic calculator.
> A double vee weld with an opening of 30 degrees in a 2” steel plate using a 60 degree shear wave in the specimen.
>The horizontal scale across the top of the card represents the number of inches between the transducer and the
center of the weld.
> The vertical scale represents specimen thickness and the arc shows the angle of the sound beam.
> The following is an example of a typical angle beam inspection using the ultrasonic calculator.
> A double vee weld with an opening of 30 degrees in a 2” steel plate using a 60 degree shear wave in the specimen.
DISCONTINUITY
trat
> The following procedure should be used in setting up the calculator:
ı. Draw a line representing the sound path from the upper left corner through the 60 degree mark on the arc,
extending to the 2" point representing the plate thickness. Calibrate the horizontal sweep of the CRT to
represent beam travel distance in the material being tested.
2 To show the full skip distance of the sound beam, you then double the 3 7/16" and mark that point at
approximately 6 7/8" (point "b" above)
3. Next, draw the 30 degree vee weld on the plastic slide or transparent paper that slides back and forth over
the calculator.
4. As shown above, a discontinuity is displayed on the crt screen at 5.5". The operator then measures the
distance between the center of the transducer (exit point) and the center of the weldment (4 5/8") and
slides the transparent paper to the same distance.
s. The position of the discontinuity is indicated and can be evaluated.
trat
> The following procedure should be used in setting up the calculator:
ı. Draw a line representing the sound path from the upper left corner through the 60 degree mark on the arc,
extending to the 2" point representing the plate thickness. Calibrate the horizontal sweep of the CRT to
represent beam travel distance in the material being tested.
2 To show the full skip distance of the sound beam, you then double the 3 7/16" and mark that point at
approximately 6 7/8" (point "b" above)
3. Next, draw the 30 degree vee weld on the plastic slide or transparent paper that slides back and forth over
the calculator.
4. As shown above, a discontinuity is displayed on the crt screen at 5.5". The operator then measures the
distance between the center of the transducer (exit point) and the center of the weldment (4 5/8") and
slides the transparent paper to the same distance.
s. The position of the discontinuity is indicated and can be evaluated.
ARTICLE 4 Figure T-434.2.1 ASME BPVC.V-2023
Nonpiping Calibration Blocks
K—
6 in. [Note (11 (180 mm)
_
127
TNote (I —|
ae Dinote it
Minimum dimensions
D = 12 in. (18 mm)
Width = 6 in. (150 mm)
Length = 3 x Thickness
Cladding (if present)
Notch Dimensions, in. (mm)
Notch depth = 1.6% T to 2.2% T
Notch width = % (6) m
Notch length = 1 (25) min.
Calibration Block Thickness (7), Hole Diameter,
Weld Thickness (¢), in. (mm) in. (mm) in. (mm)
=1 (25) A QD ore Yu (2.5)
=1 225) through 2 (50) 1%, (58) or € 78)
22 (250) through 4 (100) 35) ore ro (5)
=4 (100) +1 (25) [Note (2)]
Nonpiping Calibration Blocks
K—
6 in. [Note (11 (180 mm)
_
127
TNote (I —|
ae Dinote it
Minimum dimensions
D = 12 in. (18 mm)
Width = 6 in. (150 mm)
Length = 3 x Thickness
Cladding (if present)
Notch Dimensions, in. (mm)
Notch depth = 1.6% T to 2.2% T
Notch width = % (6) m
Notch length = 1 (25) min.
Calibration Block Thickness (7), Hole Diameter,
Weld Thickness (¢), in. (mm) in. (mm) in. (mm)
=1 (25) A QD ore Yu (2.5)
=1 225) through 2 (50) 1%, (58) or € 78)
22 (250) through 4 (100) 35) ore ro (5)
=4 (100) +1 (25) [Note (2)]
GENERAL NOTES:
(a) Holes shall be drilled and reamed 1.5 in. (38 mm) deep minimum, essentially parallel to the examination surface.
(b) For components equal to or less than 20 in. (500 mm) in diameter, calibration block diameter shall meet the requirements
of T-434.1.7.2. Two sets of calibration reflectors (holes, notches) oriented 90 deg from each other shall be used. Alternatively, two
curved calibration blocks may be used.
(c) The tolerance for hole diameter shall be +1/32 in. (0.8 mm). The tolerance for hole location through the calibration block
thickness (i.e., distance from the examination surface) shall be +1/8 in. (3 mm).
(d) For blocks less than 3/4 in. (19 mm) in thickness, only the 1/2T side-drilled hole and surface notches are required.
(e) All holes may be located on the same face (side) of the calibration block, provided care is exercised to locate all the reflectors
(holes, notches) to prevent one reflector from affecting the indication from another reflector during calibration. Notches
may also be in the same plane as the inline holes (see Nonmandatory Appendix J, Figure J-431). As in Figure J-431, a sufficient number
of holes shall be provided for both angle and straight beam calibrations at the 1/4T, 1/2T, and 3/AT depths.
(f) When cladding is present, notch depth on the cladding side of the block shall be increased by the cladding thickness, CT (i.e.,
1.6% T + CT minimum to 2.2% T + CT maximum).
(g) Maximum notch width is not critical. Notches may be made by EDM or with end mills up to 1/4 in. (6.4 mm) in diameter.
(h) Weld thickness, t, is the nominal material thickness for welds without reinforcement or, for welds with reinforcement, the
nominal material thickness plus the estimated weld reinforcement not to exceed the maximum permitted by the referencing
Code Section. When two or more base material thicknesses are involved, the calibration block thickness, T, shall be determined by the
average thickness of the weld; alternatively, a calibration block based on the greater base material thickness
may be used provided the reference reflector size is based upon the average weld thickness.
NOTES:
(1) Minimum dimension.
(2) For each increase in weld thickness of 2 in. (50 mm) or fraction thereof over 4 in. (100 mm), the hole diameter shall increase
1/16 in. (1.5 mm).
(a) Holes shall be drilled and reamed 1.5 in. (38 mm) deep minimum, essentially parallel to the examination surface.
(b) For components equal to or less than 20 in. (500 mm) in diameter, calibration block diameter shall meet the requirements
of T-434.1.7.2. Two sets of calibration reflectors (holes, notches) oriented 90 deg from each other shall be used. Alternatively, two
curved calibration blocks may be used.
(c) The tolerance for hole diameter shall be +1/32 in. (0.8 mm). The tolerance for hole location through the calibration block
thickness (i.e., distance from the examination surface) shall be +1/8 in. (3 mm).
(d) For blocks less than 3/4 in. (19 mm) in thickness, only the 1/2T side-drilled hole and surface notches are required.
(e) All holes may be located on the same face (side) of the calibration block, provided care is exercised to locate all the reflectors
(holes, notches) to prevent one reflector from affecting the indication from another reflector during calibration. Notches
may also be in the same plane as the inline holes (see Nonmandatory Appendix J, Figure J-431). As in Figure J-431, a sufficient number
of holes shall be provided for both angle and straight beam calibrations at the 1/4T, 1/2T, and 3/AT depths.
(f) When cladding is present, notch depth on the cladding side of the block shall be increased by the cladding thickness, CT (i.e.,
1.6% T + CT minimum to 2.2% T + CT maximum).
(g) Maximum notch width is not critical. Notches may be made by EDM or with end mills up to 1/4 in. (6.4 mm) in diameter.
(h) Weld thickness, t, is the nominal material thickness for welds without reinforcement or, for welds with reinforcement, the
nominal material thickness plus the estimated weld reinforcement not to exceed the maximum permitted by the referencing
Code Section. When two or more base material thicknesses are involved, the calibration block thickness, T, shall be determined by the
average thickness of the weld; alternatively, a calibration block based on the greater base material thickness
may be used provided the reference reflector size is based upon the average weld thickness.
NOTES:
(1) Minimum dimension.
(2) For each increase in weld thickness of 2 in. (50 mm) or fraction thereof over 4 in. (100 mm), the hole diameter shall increase
1/16 in. (1.5 mm).
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ARTICLE 4
Figure T-434.3-1
ros Ss /C.V-2023
Calibration Block for Piping FRERE"
[* L Nominal wall
Tr thickness (7)
Arc length
[Note] Note (1)
m
Û
Cladding (if present)
Figure T-434.3-1
ros Ss /C.V-2023
Calibration Block for Piping FRERE"
[* L Nominal wall
Tr thickness (7)
Arc length
[Note] Note (1)
m
Û
Cladding (if present)
GENERAL NOTES:
(a)
(b) For O.D. 4 in. (100 mm) or less, the minimum arc length shall be 75% of the circumference.
(c) Notch depths shall be from 8% minimum to 11% T maximum. When cladding is present, notch depths on the
cladding side of the block shall be increased by the cladding thickness, CT (i.e., 8% T + CT minimum to 11% T + CT
maximum).
~ Notch widths shall be 1/4 in. (6 mm) maximum. Notch lengths shall be 1 in. (25 mm) minimum.
(d} Maximum notch width is not critical.
Notches may be made with EDM or with end mills up to 1/4 in. (6 mm) in diameter.
(e) Notch lengths shall be sufficient to provide for calibration with a minimum 3 to 1 signal-to-noise ratio.
(f) Two blocks shall be used when a weld joining two different thicknesses of material is examined and a single block does
not satisfy the requirements of T-434.3.
(g) When a flat block is used as permitted by T-434.1.7.1, the two axial notches may be omitted and the block width may
be reduced to 4 in. (100 mm), provided the 1.D. and O.D. notches are placed on opposite examination surfaces of the
block. When cladding is not present, only one notch is required provided each examination surface is accessible during
calibrations.
NOTE:
aan
(a)
(b) For O.D. 4 in. (100 mm) or less, the minimum arc length shall be 75% of the circumference.
(c) Notch depths shall be from 8% minimum to 11% T maximum. When cladding is present, notch depths on the
cladding side of the block shall be increased by the cladding thickness, CT (i.e., 8% T + CT minimum to 11% T + CT
maximum).
~ Notch widths shall be 1/4 in. (6 mm) maximum. Notch lengths shall be 1 in. (25 mm) minimum.
(d} Maximum notch width is not critical.
Notches may be made with EDM or with end mills up to 1/4 in. (6 mm) in diameter.
(e) Notch lengths shall be sufficient to provide for calibration with a minimum 3 to 1 signal-to-noise ratio.
(f) Two blocks shall be used when a weld joining two different thicknesses of material is examined and a single block does
not satisfy the requirements of T-434.3.
(g) When a flat block is used as permitted by T-434.1.7.1, the two axial notches may be omitted and the block width may
be reduced to 4 in. (100 mm), provided the 1.D. and O.D. notches are placed on opposite examination surfaces of the
block. When cladding is not present, only one notch is required provided each examination surface is accessible during
calibrations.
NOTE:
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QiVision
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SKILL INOIA MOVEMENT + Extlain by Vishe Dandy y
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
ULTRASONIC TRANSDUCERS AND
STANDARD REFERENCE BLOCKS.
METHOD LEVEL Ihé. III
ULTRASONIC TRANSDUCERS AND
STANDARD REFERENCE BLOCKS.
Course Contains
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
NOM B wn ep
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
NOM B wn ep
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya
https://www.linkedin.com/in/vishal-dhameliya-07605a4a/|
= ULTRASONIC TRANSDUCA)S AM
STANDARD REFERENCE 13
TIEN} f
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
ULTRASONIC TESTING )
METHOD LEV
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya
https://www.linkedin.com/in/vishal-dhameliya-07605a4a/|
= ULTRASONIC TRANSDUCA)S AM
STANDARD REFERENCE 13
TIEN} f
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
ULTRASONIC TESTING )
METHOD LEV
2 Ultrasonic transducers and standard reference blocks
> The ultrasonic TRANSDUCER is the heart of the UT test a.
SEALED CASE
SIGNAL
CONNECTOR
BACKING
GROUND
CONNECTOR
ELECTRODES CRYSTAL
> The crystal material in an ultrasonic transducer is made of piezo-electric materials such as quartz, lithium sulfate
and polarized ceramics.
1. Quartz was the first material used. It has very stable frequency characteristics. However, quartz is a poor
generator of acoustic energy and has generally been replaced by more efficient materials.
2. Lithium sulfate is a very efficient receiver of acoustic energy, but is fragile, soluble in water and limited to use at
temperatures below 165°F (73.8889°C).
3. Polarized ceramics produce the most efficient generators of acoustic energy but they do have a tendency to
wear.
Common polarized ceramics include barium titanate, lead metaniobate, and lead zirconate/titanate.
> The ultrasonic TRANSDUCER is the heart of the UT test a.
SEALED CASE
SIGNAL
CONNECTOR
BACKING
GROUND
CONNECTOR
ELECTRODES CRYSTAL
> The crystal material in an ultrasonic transducer is made of piezo-electric materials such as quartz, lithium sulfate
and polarized ceramics.
1. Quartz was the first material used. It has very stable frequency characteristics. However, quartz is a poor
generator of acoustic energy and has generally been replaced by more efficient materials.
2. Lithium sulfate is a very efficient receiver of acoustic energy, but is fragile, soluble in water and limited to use at
temperatures below 165°F (73.8889°C).
3. Polarized ceramics produce the most efficient generators of acoustic energy but they do have a tendency to
wear.
Common polarized ceramics include barium titanate, lead metaniobate, and lead zirconate/titanate.
> The capability of a transducer is described by three terms:
1. Sensitivity - the ability to detect small discontinuities.
2. Resolution - the ability to separate the sound reflections from two discontinuities close together in depth or
time.
3. Efficiency - energy conversion effectiveness.
> Sensitivity of a transducer is rated by its ability to detect a certain size flat-bottom hole, at a specified depth, in a
standard reference block.
> The smaller the detectable hole, the greater the sensi YA
> Transducer sensitivity is measured by the amplitude of its response from an artificial discontinuity in a standard
reference block.
> The reference block is necessary, because even transducers of the same size, frequency and material do not
always produce the same an == == TRANSDUCER
LO
< REFERENCE
BLOCK
FLAT BOTTOMED HOLE
1. Sensitivity - the ability to detect small discontinuities.
2. Resolution - the ability to separate the sound reflections from two discontinuities close together in depth or
time.
3. Efficiency - energy conversion effectiveness.
> Sensitivity of a transducer is rated by its ability to detect a certain size flat-bottom hole, at a specified depth, in a
standard reference block.
> The smaller the detectable hole, the greater the sensi YA
> Transducer sensitivity is measured by the amplitude of its response from an artificial discontinuity in a standard
reference block.
> The reference block is necessary, because even transducers of the same size, frequency and material do not
always produce the same an == == TRANSDUCER
LO
< REFERENCE
BLOCK
FLAT BOTTOMED HOLE
aoa»
Dos»
ret eo (
Fi © À
Fo NR
FG NY
Dos»
ret eo (
Fi © À
Fo NR
FG NY
> Resolution is the ability to separate (distinguish between) the sound reflections. From a discontinuity close to a
boundary or two discontinuities close together in depth or time.
POOR RESOLUTION GOOD RESOLUTION
REFLECTION REFLECTION
DISCONTINUITY DISCONTINUITY
boundary or two discontinuities close together in depth or time.
POOR RESOLUTION GOOD RESOLUTION
REFLECTION REFLECTION
DISCONTINUITY DISCONTINUITY
> Transducer materials are usually cut in two ways:
1. Crystals cut perpendicular to the X-axis produce longitudinal waves.
2. Crystals cut perpendicular to the Y-axis produce shear waves.
> As shown below, most crystals used for UT are cut perpendicular to the x-axis. v
CRYSTAL DEFORMATION AG
AXIS X-AXIS f
Velocity
wavelength = ————_
Frequency
Y-AXIS.
: A
a Sing = 1.22 a
> Size is a contributing factor in performance of a transducer.
1. The larger diameter the transducer, the less the sound beam will spread for a given frequency.
2. However, the small, high frequency transducers are better able to detect very small discontinuities.
3. The larger the transducer, the more sound energy it transmits into the test part. Large low frequency transducers
are often used to get more penetration.
4, Large single crystal transducers are generally limited to the lower frequencies. High frequency crystals are
susceptible to damage because they are very thin.
1. Crystals cut perpendicular to the X-axis produce longitudinal waves.
2. Crystals cut perpendicular to the Y-axis produce shear waves.
> As shown below, most crystals used for UT are cut perpendicular to the x-axis. v
CRYSTAL DEFORMATION AG
AXIS X-AXIS f
Velocity
wavelength = ————_
Frequency
Y-AXIS.
: A
a Sing = 1.22 a
> Size is a contributing factor in performance of a transducer.
1. The larger diameter the transducer, the less the sound beam will spread for a given frequency.
2. However, the small, high frequency transducers are better able to detect very small discontinuities.
3. The larger the transducer, the more sound energy it transmits into the test part. Large low frequency transducers
are often used to get more penetration.
4, Large single crystal transducers are generally limited to the lower frequencies. High frequency crystals are
susceptible to damage because they are very thin.
> The frequency of a transducer is an important factor in its application.
1. The higher the frequency of a transducer, the less the sound beam will spread and the greater the sensitivity and resolution
> When the sound beam is spread as shown below, less sound is likely to be reflected from a small discontinuity.
HIGH FREQUENCY TRANSDUCER LOW FREQUENCY TRANSDUCER
A
D
DISCONTINUITY
SIND = 1.22
fant
maria]
"
FIG. 1A FIG. 18
2. The higher the frequency, the deeper the sound penetration and the Low scatter. The greater beam spread aids
in detecting reflectors which are not perpendicular to the axis of the sound beam.
3. Crystal thickness is also related to transducer frequency. The higher the frequency of the transducer, the
thinner the crystal will be.
Most ultrasonic testing is done between 0.2 MHz and 25 MHz and crystals cut for use above 10 MHz are too thin
and fragile for contact testing.
Therefore, transducers with operating frequencies above 10 MHz are used primarily for immersion testing.
1. The higher the frequency of a transducer, the less the sound beam will spread and the greater the sensitivity and resolution
> When the sound beam is spread as shown below, less sound is likely to be reflected from a small discontinuity.
HIGH FREQUENCY TRANSDUCER LOW FREQUENCY TRANSDUCER
A
D
DISCONTINUITY
SIND = 1.22
fant
maria]
"
FIG. 1A FIG. 18
2. The higher the frequency, the deeper the sound penetration and the Low scatter. The greater beam spread aids
in detecting reflectors which are not perpendicular to the axis of the sound beam.
3. Crystal thickness is also related to transducer frequency. The higher the frequency of the transducer, the
thinner the crystal will be.
Most ultrasonic testing is done between 0.2 MHz and 25 MHz and crystals cut for use above 10 MHz are too thin
and fragile for contact testing.
Therefore, transducers with operating frequencies above 10 MHz are used primarily for immersion testing.
> Transducers for contact testing and immersion testing are essentially the same but usually are not
interchangeable.
> Most contact testing transducers have wear plates OR membrane or rubber plate in front of the piezoelectric
element to protect it. The exception to this is a quartz transducer.
As!
. TRANSDUCER A TRANSDUCER B
7 , Y
CERAMIC
> Straight beam transducers usually have a lucite, ceramic, or quartz wear plate in front of the crystal.
> Angle beam transducers have the wear plate wedge-shaped to produce the desired refracted angle.
> As shown above, the lucite wedge protects the face of the crystal and determines the angle of incidence of the
sound beam on the test part.
> As has been discussed, when sound waves are directed into the test part at an angle, they are divided into
longitudinal and shear waves by refraction.
interchangeable.
> Most contact testing transducers have wear plates OR membrane or rubber plate in front of the piezoelectric
element to protect it. The exception to this is a quartz transducer.
As!
. TRANSDUCER A TRANSDUCER B
7 , Y
CERAMIC
> Straight beam transducers usually have a lucite, ceramic, or quartz wear plate in front of the crystal.
> Angle beam transducers have the wear plate wedge-shaped to produce the desired refracted angle.
> As shown above, the lucite wedge protects the face of the crystal and determines the angle of incidence of the
sound beam on the test part.
> As has been discussed, when sound waves are directed into the test part at an angle, they are divided into
longitudinal and shear waves by refraction.
> Most angle beam testing is done with shear waves.
STRAIGHT BEAM TRANSDUCER ANGLE BEAM TRANSDUCER
LONGITUDINAL SHEAR
WAVES WAVES
> The angle beam probe can also be used to generate surface waves.
> As we have discussed, surface waves are generated when the incident angle of the sound beam reaches the
second or upper critical angle.
> Most angle beam contact transducers are identified by the refracted shear wave produced (45 °, 60°, 70°,
etc.), In a specific material, usually steel and aluminum.
STRAIGHT BEAM TRANSDUCER ANGLE BEAM TRANSDUCER
LONGITUDINAL SHEAR
WAVES WAVES
> The angle beam probe can also be used to generate surface waves.
> As we have discussed, surface waves are generated when the incident angle of the sound beam reaches the
second or upper critical angle.
> Most angle beam contact transducers are identified by the refracted shear wave produced (45 °, 60°, 70°,
etc.), In a specific material, usually steel and aluminum.
>Spherically ground and cylindrically ground acoustical lenses are commonly added to immersion type
transducers. They are used to.
1, Improve sensitivity and resolution.
2. Compensate for test part contours.
3. Examine a given depth of the test part more carefully.
> As shown below, cylindrically ground lenses focus the sound energy to a line. Spherically ground lenses focus
the sound energy to a point.
transducers. They are used to.
1, Improve sensitivity and resolution.
2. Compensate for test part contours.
3. Examine a given depth of the test part more carefully.
> As shown below, cylindrically ground lenses focus the sound energy to a line. Spherically ground lenses focus
the sound energy to a point.
> Cylindrical lenses are used in two ways:
1. To increase the sensitivity and resolution of equipment.
2. For contour correction as shown below. The lens can be ground specially to direct the sound energy normal
(perpendicular) to a curved surface at all points.
m tae
CORRECTION
LENS
CRT SCREEN DISPLAY
FLAT SHOE
>
a
view A VIEW B
> Spherical lenses concentrate the sound energy into a cone shaped beam.
1. The focusing increases its intensity, but shortens its useful range.
2. While the cylinderical lens above has a greater width, the spherical lens has the greatest sensitivity.
3. The spherical lens is often used when immersion testing parts having a rough surface.
1. To increase the sensitivity and resolution of equipment.
2. For contour correction as shown below. The lens can be ground specially to direct the sound energy normal
(perpendicular) to a curved surface at all points.
m tae
CORRECTION
LENS
CRT SCREEN DISPLAY
FLAT SHOE
>
a
view A VIEW B
> Spherical lenses concentrate the sound energy into a cone shaped beam.
1. The focusing increases its intensity, but shortens its useful range.
2. While the cylinderical lens above has a greater width, the spherical lens has the greatest sensitivity.
3. The spherical lens is often used when immersion testing parts having a rough surface.
> Focused transducers are described by their focal length.
> The short focal lengths are for examining areas of the specimen close to the surface. Longer focal lengths are
for increasingly deeper areas.
> Transducers come in many shapes, sizes and physical characteristics.
> Some common types include paint-brush, dual element, single element, angle beam, focused, mosaic, contact,
and immersion.
> Single element transducers may be transmitters only, receivers only, or both transmitter and receiver.
> Double element transducers (as shown below) may be either single transducers mounted side by side or stacked.
> In a double element transducer, one is a transmitter and the other a receiver.
RECEIVER TRANSMITTER
TRANSMITTER RECEIVER
2
SOUND BARRIER
SOUND BARRIER
SIDE BY SIDE STACKED
> The short focal lengths are for examining areas of the specimen close to the surface. Longer focal lengths are
for increasingly deeper areas.
> Transducers come in many shapes, sizes and physical characteristics.
> Some common types include paint-brush, dual element, single element, angle beam, focused, mosaic, contact,
and immersion.
> Single element transducers may be transmitters only, receivers only, or both transmitter and receiver.
> Double element transducers (as shown below) may be either single transducers mounted side by side or stacked.
> In a double element transducer, one is a transmitter and the other a receiver.
RECEIVER TRANSMITTER
TRANSMITTER RECEIVER
2
SOUND BARRIER
SOUND BARRIER
SIDE BY SIDE STACKED
> Double element transducers have better near surface resolution because the receiver can receive discontinuity
signals before the transmitter completes its transmission.
DISCONTINUITY OBSCURED
BY INITIAL PULSE COAXIAL CABLE
\ TRANSDUCER
DISCONTINUITY
TEST
SPECIMEN
2 Standard reference blocks
> In ultrasonic testing, discontinuities are usually compared to a reference standard.
> The standard may be one of many reference blocks or sets of blocks specified for a given test.
> Reference blocks come in many different shapes and sizes and this lesson will discuss only a few of those
commonly used. A typical block is shown below.
signals before the transmitter completes its transmission.
DISCONTINUITY OBSCURED
BY INITIAL PULSE COAXIAL CABLE
\ TRANSDUCER
DISCONTINUITY
TEST
SPECIMEN
2 Standard reference blocks
> In ultrasonic testing, discontinuities are usually compared to a reference standard.
> The standard may be one of many reference blocks or sets of blocks specified for a given test.
> Reference blocks come in many different shapes and sizes and this lesson will discuss only a few of those
commonly used. A typical block is shown below.
TEST SURFACE
= DIAMETER OF FBH
= METAL DISTANCE
FROM TEST
SURFACE TO FBH
METAL DISTANCE
FROM TEST
SURFACE TO
BOTTOM OF BLOCK
or
FLAT-BOTTOM HOLE
>
1. They are made from carefully selected material.
2. The material must have the proper attenuation, grain size, heat treatment and be free of discontinuities.
3. All dimensions must be precisely machined.
4. All holes must be flat-bottomed and have a specific diameter to be an ideal reflector.
5. Side drilled hole diameter must be carefully controlled.
>
1. Area amplitude blocks
2. Distance amplitude blocks
3. ASTM basic set of area and distance amplitude blocks.
> Area amplitude blocks provide standards for discontinuities of different sizes, at the same depth.
> Distance amplitude blocks provide standards for discontinuities of the same size at different depths.
= DIAMETER OF FBH
= METAL DISTANCE
FROM TEST
SURFACE TO FBH
METAL DISTANCE
FROM TEST
SURFACE TO
BOTTOM OF BLOCK
or
FLAT-BOTTOM HOLE
>
1. They are made from carefully selected material.
2. The material must have the proper attenuation, grain size, heat treatment and be free of discontinuities.
3. All dimensions must be precisely machined.
4. All holes must be flat-bottomed and have a specific diameter to be an ideal reflector.
5. Side drilled hole diameter must be carefully controlled.
>
1. Area amplitude blocks
2. Distance amplitude blocks
3. ASTM basic set of area and distance amplitude blocks.
> Area amplitude blocks provide standards for discontinuities of different sizes, at the same depth.
> Distance amplitude blocks provide standards for discontinuities of the same size at different depths.
> The ASTM basic set of area/distance amplitude blocks consists of ten, two inch diameter blocks as shown
below:
FLAT-BOTTOM
HOLE (FBH) DIA
ÚS (SEE TABLE)
1 METAL DISTANCE :
[or SEE TABLED, | [=~ 3/4 INCH
METAL DISTANCE, INCHES | we | 1/4 112 |3|3 GE
ma CS EN EN > PCM bbb]
below:
FLAT-BOTTOM
HOLE (FBH) DIA
ÚS (SEE TABLE)
1 METAL DISTANCE :
[or SEE TABLED, | [=~ 3/4 INCH
METAL DISTANCE, INCHES | we | 1/4 112 |3|3 GE
ma CS EN EN > PCM bbb]
| e 0.125"
0.25"
Y LAR T T fl
= 5 aa
o
A 0.06” HOLE
a 3.64"
_ 2" DIAMETER MOLE
=) (xa EX Al
FOCAL POINT. ZEN BEER? |
: i 4
PLASTIC INSERT
> Another type of calibration block is the IW block (international institute of welding). It provides the following:
> Verification of known distances & angular relationships, verifies transducer angle and beam exit point and checks
transducer resolution.
> In contact angle beam testing, the beam exit point of the transducer must be known to accurately determine the
location of the discontinuity.
> As shown below, the transducer is moved back and forth until the pip on the CRT reaches maximum amplitude.
> The focal point on the IIW block then corresponds with the beam exit point of the transducer.
0.25"
Y LAR T T fl
= 5 aa
o
A 0.06” HOLE
a 3.64"
_ 2" DIAMETER MOLE
=) (xa EX Al
FOCAL POINT. ZEN BEER? |
: i 4
PLASTIC INSERT
> Another type of calibration block is the IW block (international institute of welding). It provides the following:
> Verification of known distances & angular relationships, verifies transducer angle and beam exit point and checks
transducer resolution.
> In contact angle beam testing, the beam exit point of the transducer must be known to accurately determine the
location of the discontinuity.
> As shown below, the transducer is moved back and forth until the pip on the CRT reaches maximum amplitude.
> The focal point on the IIW block then corresponds with the beam exit point of the transducer.
ANGLE BEAM
BEAM EXIT POINT TRANSDUCER
FOCAL POINT | > 7
> Special calibration standards
> Special standards are often used for items such as weldments, castings, and piping. The standards are normally
of the same material and product form to be tested. Reference reflectors such as notches or holes are
artificially added to the standard.
> Verification of the transducer angle is accomplished as shown below:
> The plastic wedge of the angle beam transducer is subject to wear in normal use. This wear can change the
beam exit point and the angle of the sound beam.
BEAM EXIT POINT TRANSDUCER
FOCAL POINT | > 7
> Special calibration standards
> Special standards are often used for items such as weldments, castings, and piping. The standards are normally
of the same material and product form to be tested. Reference reflectors such as notches or holes are
artificially added to the standard.
> Verification of the transducer angle is accomplished as shown below:
> The plastic wedge of the angle beam transducer is subject to wear in normal use. This wear can change the
beam exit point and the angle of the sound beam.
BEAM EXIT POINT
a 60 DEGREE TRANSDUCER
AZT A T
40° so- 60°
2" DIAMETER HOLE
1 1 L Li
> From the position shown above, the transducer is moved back and forth until the reflection from the 2 inch
hole shows maximum amplitude on the CRT.
> The angle of sound beam can then be read from where the exit point on the transducer matches the degrees
stamped on the side of the block.
> The transducer sound beam exit point should always be checked first. If the exit point marking is not correct,
then the angle check will not be accurate.
> The far field resolving power of the test equipment can be estimated by placing a normal beam transducer on
the IIW block as shown.
> Good resolution will be indicated if the instrument can satisfactorily separate the pips from all three reflectors.
a 60 DEGREE TRANSDUCER
AZT A T
40° so- 60°
2" DIAMETER HOLE
1 1 L Li
> From the position shown above, the transducer is moved back and forth until the reflection from the 2 inch
hole shows maximum amplitude on the CRT.
> The angle of sound beam can then be read from where the exit point on the transducer matches the degrees
stamped on the side of the block.
> The transducer sound beam exit point should always be checked first. If the exit point marking is not correct,
then the angle check will not be accurate.
> The far field resolving power of the test equipment can be estimated by placing a normal beam transducer on
the IIW block as shown.
> Good resolution will be indicated if the instrument can satisfactorily separate the pips from all three reflectors.
TRANSDUCER
=!
72 ©
coop
uw BLOCK
CRT DISPLAY
> The miniature angle beam block can also be used to calibrate the instrument for angle beam inspection.
> The miniature block is intended for field work and is not as comprehensive as the larger IIW block.
E =
FOCAL POINT
0.750-
EF) 7
AAA 78-750"
MINIATURE ANGLE BEAM BLOCK
iin HOLE
=!
72 ©
coop
uw BLOCK
CRT DISPLAY
> The miniature angle beam block can also be used to calibrate the instrument for angle beam inspection.
> The miniature block is intended for field work and is not as comprehensive as the larger IIW block.
E =
FOCAL POINT
0.750-
EF) 7
AAA 78-750"
MINIATURE ANGLE BEAM BLOCK
iin HOLE
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
IMMERSION INSPECTION.
METHOD LEVEL Ihé. III
IMMERSION INSPECTION.
Course Contains
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
oN DO PB WN pap
. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
oN DO PB WN pap
. Ultrasonic Transducers And Standard Reference Blocks.
9. Immersion Inspection,
10. Ultrasonic Contact Testing and Shell’s Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya BLTRAS( INIC TESTING
https://www.linkedin.com/in/vishal-dhameliya-0760524/| "nm d
eh N + N Y.
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya BLTRAS( INIC TESTING
https://www.linkedin.com/in/vishal-dhameliya-0760524/| "nm d
eh N + N Y.
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
KA
“ Chapter 9:- Immersion Inspection.
> Immersion inspection
> Atypical immersion testing installation usually includes the items shown below.
TEST INSTRUMENT
COAXIAL CABLE
TRANSDUCER
TEST SPECIMEN
> Angle beam testing often indicates the angle of "refraction" in a given material.
> However, in immersion testing, the angle shown by the angle indicator on the manipulator is the "angle of incidence."
> It is necessary to apply snell's law and calculate the angle of refraction in the test specimen. SIN 9) _ Y
SIN 8) Vo
“ Chapter 9:- Immersion Inspection.
> Immersion inspection
> Atypical immersion testing installation usually includes the items shown below.
TEST INSTRUMENT
COAXIAL CABLE
TRANSDUCER
TEST SPECIMEN
> Angle beam testing often indicates the angle of "refraction" in a given material.
> However, in immersion testing, the angle shown by the angle indicator on the manipulator is the "angle of incidence."
> It is necessary to apply snell's law and calculate the angle of refraction in the test specimen. SIN 9) _ Y
SIN 8) Vo
> If the angle indicator showed the angle of refraction in the test specimen, it would be necessary to change the
indicator each time a different material was inspected.
> Test frequencies - since the transducer does not come into contact with the test specimen in immersion testing,
it is possible to use thinner crystals at higher ultrasonic frequencies.
> It is possible to use frequencies as high as 25 MHZ and the range is usually from 2.25 TO 25 MHZ.
> The higher frequencies give the best resolution of small discontinuities.
> For an immersion testing application where a sharper than normal sound beam is required, a focused transducer
should be used.
> The lens focuses the sound energy into a small, well-defined pattern as shown below.
TRANSDUCER ae. \\
— col Lens
7
| Ñ
\
WATER PATH p
|
Test sveracey \ !
' \
\
FOCAL ZONE | | BEAM DIAMETER
1 | FIX [e ec
FOCAL POINT
indicator each time a different material was inspected.
> Test frequencies - since the transducer does not come into contact with the test specimen in immersion testing,
it is possible to use thinner crystals at higher ultrasonic frequencies.
> It is possible to use frequencies as high as 25 MHZ and the range is usually from 2.25 TO 25 MHZ.
> The higher frequencies give the best resolution of small discontinuities.
> For an immersion testing application where a sharper than normal sound beam is required, a focused transducer
should be used.
> The lens focuses the sound energy into a small, well-defined pattern as shown below.
TRANSDUCER ae. \\
— col Lens
7
| Ñ
\
WATER PATH p
|
Test sveracey \ !
' \
\
FOCAL ZONE | | BEAM DIAMETER
1 | FIX [e ec
FOCAL POINT
> The proper water path for a focused transducer can be determined as follows:
> Using a transducer with a focal length of 5 inches in water to focus the beam to a point 0.25 inches below the
surface of a steel part, one would determine the water path distance by:
A. Dividing the velocity of steel by the velocity of the water. OT" OMISEC _,
1.5 x 10 CMISEC
B. Multiplying the desired focal depth by the answer. 4 x .25' e
C. Subtracting answer from known focal length in water. 5" - 1" = 4%
D. Thus, the water path distance must be 4" to focus the beam at .25" below the surface.
FOCUSED
TRANSDUCE
WATER
FOCAL POINT
IN WATER
vo? STEEL
> Using a transducer with a focal length of 5 inches in water to focus the beam to a point 0.25 inches below the
surface of a steel part, one would determine the water path distance by:
A. Dividing the velocity of steel by the velocity of the water. OT" OMISEC _,
1.5 x 10 CMISEC
B. Multiplying the desired focal depth by the answer. 4 x .25' e
C. Subtracting answer from known focal length in water. 5" - 1" = 4%
D. Thus, the water path distance must be 4" to focus the beam at .25" below the surface.
FOCUSED
TRANSDUCE
WATER
FOCAL POINT
IN WATER
vo? STEEL
> A special application of immersion testing is the "bubbler" or "squirter" as shown below.
SHLD. TRANSDUCER
TEST SPECIMEN —__ | TRANSDUCER CABLE
FACE PLATE
SOUND PATH
TRIGGER VALVE
BUBBLER CHAMBER WATER HOSE CONNECTION
> Both straight and angle beam techniques can be used with this process depending on the bubbler design.
e : y Y 3
TEST
SPECIMEN,
PP WATER
CCF LANT
VIEW A ¡PES TO ULTRASONIC INSTRUMENT
STRAIGHT BEAM ANGLE BEAM
SHLD. TRANSDUCER
TEST SPECIMEN —__ | TRANSDUCER CABLE
FACE PLATE
SOUND PATH
TRIGGER VALVE
BUBBLER CHAMBER WATER HOSE CONNECTION
> Both straight and angle beam techniques can be used with this process depending on the bubbler design.
e : y Y 3
TEST
SPECIMEN,
PP WATER
CCF LANT
VIEW A ¡PES TO ULTRASONIC INSTRUMENT
STRAIGHT BEAM ANGLE BEAM
> An advantage of the bubbler is that no immersion tank is required.
> A technique similar to the bubbler is used in contact testing and utilizes an "irrigated search unit."
> The couplant (water) can be fed to the test surface through a series of holes in a plastic block.
> The following show a typical straight beam immersion operation with the CRT indication that would be received.
BACK REFLECTION
DISCONTINUITY
FRONT SURFACE
TRANSDUCER
FRONT SURFACE
INITIAL PULSE.
BACK SURFACE
WATER,
PATH
> A technique similar to the bubbler is used in contact testing and utilizes an "irrigated search unit."
> The couplant (water) can be fed to the test surface through a series of holes in a plastic block.
> The following show a typical straight beam immersion operation with the CRT indication that would be received.
BACK REFLECTION
DISCONTINUITY
FRONT SURFACE
TRANSDUCER
FRONT SURFACE
INITIAL PULSE.
BACK SURFACE
WATER,
PATH
> The water path distance from the transducer to the front surface of the test part is generally set to be longer in
time than the metal part time from the front to rear of the test specimen.
> If the transducer is too close to the front surface of the test part the second front reflection will appear on the
CRT between the front and back surface reflections. This reflection may appear to be a discontinuity.
BACK REFLECTION
TRANSDUCER
FRONT SURFACE
WATER DISTANCE.
V2" tint
PULSE
\\
TEST SPECIMEN
N
> The velocity of sound in water is about 114 that of aluminum or steel. One inch of water will appear on the crt
in the same time span on the sweep as 4 inches of steel. Therefore, a rule of thumb is - use at least one inch of
water path for each four inches of metal path, plus 1/4".
time than the metal part time from the front to rear of the test specimen.
> If the transducer is too close to the front surface of the test part the second front reflection will appear on the
CRT between the front and back surface reflections. This reflection may appear to be a discontinuity.
BACK REFLECTION
TRANSDUCER
FRONT SURFACE
WATER DISTANCE.
V2" tint
PULSE
\\
TEST SPECIMEN
N
> The velocity of sound in water is about 114 that of aluminum or steel. One inch of water will appear on the crt
in the same time span on the sweep as 4 inches of steel. Therefore, a rule of thumb is - use at least one inch of
water path for each four inches of metal path, plus 1/4".
> Angle beam testing with immersion techniques is illustrated below:
TRANSDUCER WATER
INITIAL PULSE FRONT SURFACE DISCONTINUITY.
TEST SPECIMEN
Le
o
FAR
/
NN DISCONTINUITY
> Angle beam testing, only a small surface indication, if any, will result because most of the sound is reflected from
the part surface away from the transducer.
> Remember, that shear waves will not propagate in water.
> With immersion testing a c-scan is commonly used to display the shape and relative size of a discontinuity as shown below.
> When a defect is found on the c-scan, it is possible to go back and manually determine its depth below the surface.
Y,
TRANSDUCER WATER
INITIAL PULSE FRONT SURFACE DISCONTINUITY.
TEST SPECIMEN
Le
o
FAR
/
NN DISCONTINUITY
> Angle beam testing, only a small surface indication, if any, will result because most of the sound is reflected from
the part surface away from the transducer.
> Remember, that shear waves will not propagate in water.
> With immersion testing a c-scan is commonly used to display the shape and relative size of a discontinuity as shown below.
> When a defect is found on the c-scan, it is possible to go back and manually determine its depth below the surface.
Y,
TRANSDUCER _
TN MECHANICAL RECORDING
LINKAGE PAPER
DRUM
DISCONTINUITY
|
MOTION WITH TRANSDUCER
MOVEMENT
> Determining the position of a discontinuity in the specimen with immersion testing is shown below
> If the sound beam is striking the surface at an angle, refraction of the sound has to be taken into consideration.
TN MECHANICAL RECORDING
LINKAGE PAPER
DRUM
DISCONTINUITY
|
MOTION WITH TRANSDUCER
MOVEMENT
> Determining the position of a discontinuity in the specimen with immersion testing is shown below
> If the sound beam is striking the surface at an angle, refraction of the sound has to be taken into consideration.
METAL SPOON
AE
T\ FAST“
=.
x x
> Point at which the sound beam strikes the surface can be determined by placing a straight edged piece of metal
“metal spoon" on the surface (a 6" steel ruler can be used).
> As soon as the leading edge of the metal spoon enters the sound beam an indication will appear on the CRT.
5* ANGLE OF INCIDENCE
20° ANGLE OF
REFRACTION
> The same check is then performed from the other 3 sides, and this locates the area in which the sound enters the
specimen.
> Conventional methods of identifying the location of the discontinuity can be used, such as utilizing the ultrasonic
calculator or similar techniques.
> Remember that plate waves can be produced in immersion testing but shear waves will not propagate in water.
Although shear waves and plate waves will not propagate in liquids, both modes can be used in immersion testing
because the sonic energy is transmitted through the water as longitudinal waves. The longitudinal waves are mode
converted to s ear or plate waves upon entering the solid part and then the reflected shear or plate wave is mode
converted back to longitudinal waves, which then propagate to the transducer through the liquid couplant.
AE
T\ FAST“
=.
x x
> Point at which the sound beam strikes the surface can be determined by placing a straight edged piece of metal
“metal spoon" on the surface (a 6" steel ruler can be used).
> As soon as the leading edge of the metal spoon enters the sound beam an indication will appear on the CRT.
5* ANGLE OF INCIDENCE
20° ANGLE OF
REFRACTION
> The same check is then performed from the other 3 sides, and this locates the area in which the sound enters the
specimen.
> Conventional methods of identifying the location of the discontinuity can be used, such as utilizing the ultrasonic
calculator or similar techniques.
> Remember that plate waves can be produced in immersion testing but shear waves will not propagate in water.
Although shear waves and plate waves will not propagate in liquids, both modes can be used in immersion testing
because the sonic energy is transmitted through the water as longitudinal waves. The longitudinal waves are mode
converted to s ear or plate waves upon entering the solid part and then the reflected shear or plate wave is mode
converted back to longitudinal waves, which then propagate to the transducer through the liquid couplant.
> Immersion testing techniques are commonly used for the inspection of thin and thick wall tubing and pipe as shown
below. BACK SURFACE DISCONTINUITY
DISCONTINUITY IN WELD FRONT SURFACE y
.125 MIN
VIEW A VIEW B
> Immersion techniques can also be used to inspect butt welds as shown below.
FRONT SURFACE DISCONTINUITY.
DISCONTINUITY
below. BACK SURFACE DISCONTINUITY
DISCONTINUITY IN WELD FRONT SURFACE y
.125 MIN
VIEW A VIEW B
> Immersion techniques can also be used to inspect butt welds as shown below.
FRONT SURFACE DISCONTINUITY.
DISCONTINUITY
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
ULTRASONIC CONTACT TESTING
AND SHELL'S LAW
METHOD LEVEL Ihé. III
ULTRASONIC CONTACT TESTING
AND SHELL'S LAW
Course Contains
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
dl
=
3
4.
5. Couplant, Ultrasonic Sound Energy & Materials Characteristics
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9
|. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell's Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
dl
=
3
4.
5. Couplant, Ultrasonic Sound Energy & Materials Characteristics
6. Attenuation, Acoustic Impedance, And Resonance.
7. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
8. Ultrasonic Transducers And Standard Reference Blocks.
9
|. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell's Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya ULTR AS IC ESTING
hitps://www.linkedin.com/in/vishal-dhameliya-07605a4a/ DD EIER
> CHAPTER-10f
"EST eg and NDT Creat Rena
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya ULTR AS IC ESTING
hitps://www.linkedin.com/in/vishal-dhameliya-07605a4a/ DD EIER
> CHAPTER-10f
"EST eg and NDT Creat Rena
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
% Chapter 10:- Ultrasonic Contact Testing.
> Ultrasonic contact testing
> Through transmission testing usually uses the pitch-catch technique as shown below:
TRANSMITTER RECEIVER
RELATIVE AMPLITUDE
> When using through transmission, the CRT indication decreases when more sound energy is intercepted by a
discontinuity.
> Total reflection of sound energy at an internal reflector will Result in no energy being received by the receiving
transducer.
> Ultrasonic contact testing
> Through transmission testing usually uses the pitch-catch technique as shown below:
TRANSMITTER RECEIVER
RELATIVE AMPLITUDE
> When using through transmission, the CRT indication decreases when more sound energy is intercepted by a
discontinuity.
> Total reflection of sound energy at an internal reflector will Result in no energy being received by the receiving
transducer.
> Through transmission has certain advantages:
1. Better near surface detection - defects that are only a few thousandths of an inch below the surface can be
detected effectively.
2. Capability of testing thicker test specimens (less attenuation)
> However, a through transmission technique cannot "see" the discontinuity. It only shows a loss of sound energy.
> If the transmitted pulse and received pulse are of the same relative height on the CRT, it can be assumed the
specimen is sound and there is no significant attenuation in the material.
> In contact testing, it is possible to use sound beams that:
1. Are perpendicular to the test surface.
2. Propagate into the specimen at an angle.
3. Propagate along the surface of the specimen.
4. Propagate through the material from one side to the other.
> The determination of the proper equipment to use depends on several factors including:
1. Nature, size and orientation of discontinuities.
2. Surface condition and shape of the test specimen.
3. Internal structure (coarse grained or fine grained).
> It is usually desirable to test at the lowest frequency that will locate specified minimum-size discontinuities.
> Listed below are frequency ranges and test applications that are commonly used.
1. Better near surface detection - defects that are only a few thousandths of an inch below the surface can be
detected effectively.
2. Capability of testing thicker test specimens (less attenuation)
> However, a through transmission technique cannot "see" the discontinuity. It only shows a loss of sound energy.
> If the transmitted pulse and received pulse are of the same relative height on the CRT, it can be assumed the
specimen is sound and there is no significant attenuation in the material.
> In contact testing, it is possible to use sound beams that:
1. Are perpendicular to the test surface.
2. Propagate into the specimen at an angle.
3. Propagate along the surface of the specimen.
4. Propagate through the material from one side to the other.
> The determination of the proper equipment to use depends on several factors including:
1. Nature, size and orientation of discontinuities.
2. Surface condition and shape of the test specimen.
3. Internal structure (coarse grained or fine grained).
> It is usually desirable to test at the lowest frequency that will locate specified minimum-size discontinuities.
> Listed below are frequency ranges and test applications that are commonly used.
————————]————________—
FREQUENCY RANGE TEST APPLICATIONS
200 KHz-1 MHz CASTINGS: GRAY IRON, NODULAR IRON, AND RELATIVELY COARSE-
GRAINED MATERIALS, SUCH AS COPPER AND STAINLESS STEELS.
400 KH2-5 MHz CASTINGS: STEEL, ALUMINUM, BRASS, AND OTHER MATERIALS
WITH REFINED GRAIN SIZE.
200 KHz2.25MHz PLASTICS AND PLASTIC-LIKE MATERIALS, SUCH AS SOLID
ROCKET PROPELLANTS AND POWDER GRAINS,
1-5 MHz ROLLED PRODUCTS: METALLIC SHEET, PLATE, BARS, AND BILLETS.
2.25-10 MHz DRAWN AND EXTRUDED PRODUCTS: BARS, TUBES, AND SHAPES
1-10 MHz FORGINGS
2.25-10 MHz GLASS AND CERAMICS.
1-2.25 MHz WELDS
ESPECIALLY FATIGUE CRACKS.
1-10 MHz MAINTENANCE INSPECTION
FREQUENCY RANGE TEST APPLICATIONS
200 KHz-1 MHz CASTINGS: GRAY IRON, NODULAR IRON, AND RELATIVELY COARSE-
GRAINED MATERIALS, SUCH AS COPPER AND STAINLESS STEELS.
400 KH2-5 MHz CASTINGS: STEEL, ALUMINUM, BRASS, AND OTHER MATERIALS
WITH REFINED GRAIN SIZE.
200 KHz2.25MHz PLASTICS AND PLASTIC-LIKE MATERIALS, SUCH AS SOLID
ROCKET PROPELLANTS AND POWDER GRAINS,
1-5 MHz ROLLED PRODUCTS: METALLIC SHEET, PLATE, BARS, AND BILLETS.
2.25-10 MHz DRAWN AND EXTRUDED PRODUCTS: BARS, TUBES, AND SHAPES
1-10 MHz FORGINGS
2.25-10 MHz GLASS AND CERAMICS.
1-2.25 MHz WELDS
ESPECIALLY FATIGUE CRACKS.
1-10 MHz MAINTENANCE INSPECTION
VVVV
VVVVVVVV
A low test frequency is required to test a specimen that has a coarse grained internal structure, such as a casting.
A surface that is rough or pitted with corrosion will also require low frequencies to give proper sensitivity.
Sometimes it is possible to sand or grind the surface of the specimen to obtain better transducer contact.
A high test frequency is often used for fine grained materials because the lower frequency will not detect the
desired discontinuity.
At higher frequencies, the wavelength is short in relation to the grain size.
Considerations:
A higher frequency will provide the greatest sensitivity for detecting small defects.
A lower frequency will give greater power to penetrate more deeply.
A larger diameter transducer may be required when testing thicker materials.
At any frequency, the larger the crystal, the straighter the beam.
For a transducer of a given diameter, there is less beam spread at higher frequencies.
If you were inspecting a long bar through its length (8 ft), which of the following would you select?
1/2” - 5 MHz, OR 1/2” - 2.25 MHz, OR 1” - 2.25 MHz, OR 1” - 5 MHz
THE 1” - 2.25 MHZ WOULD BE THE BEST CHOICE.
VVVVVVVV
A low test frequency is required to test a specimen that has a coarse grained internal structure, such as a casting.
A surface that is rough or pitted with corrosion will also require low frequencies to give proper sensitivity.
Sometimes it is possible to sand or grind the surface of the specimen to obtain better transducer contact.
A high test frequency is often used for fine grained materials because the lower frequency will not detect the
desired discontinuity.
At higher frequencies, the wavelength is short in relation to the grain size.
Considerations:
A higher frequency will provide the greatest sensitivity for detecting small defects.
A lower frequency will give greater power to penetrate more deeply.
A larger diameter transducer may be required when testing thicker materials.
At any frequency, the larger the crystal, the straighter the beam.
For a transducer of a given diameter, there is less beam spread at higher frequencies.
If you were inspecting a long bar through its length (8 ft), which of the following would you select?
1/2” - 5 MHz, OR 1/2” - 2.25 MHz, OR 1” - 2.25 MHz, OR 1” - 5 MHz
THE 1” - 2.25 MHZ WOULD BE THE BEST CHOICE.
> Before making an ultrasonic test, be sure the instrument is operating properly, check the instrument on a
standard in accordance with the operating manual.
> Before conducting a test, you should have a clear idea of the kind, orientation, and quantity of discontinuities
you are trying to detect.
> If the rear surface of the specimen lies at an angle as shown below, what will be the effect on a normal a-scan display?
TRANSDUCER
INCIDENT BEAM
) PAL
REFLECTED BEAM
$, =20*
$, =20*
7
1
I
!
dé
1
ny
Er
“fil
AA
TEST SPECIMEN
standard in accordance with the operating manual.
> Before conducting a test, you should have a clear idea of the kind, orientation, and quantity of discontinuities
you are trying to detect.
> If the rear surface of the specimen lies at an angle as shown below, what will be the effect on a normal a-scan display?
TRANSDUCER
INCIDENT BEAM
) PAL
REFLECTED BEAM
$, =20*
$, =20*
7
1
I
!
dé
1
ny
Er
“fil
AA
TEST SPECIMEN
> Although a discontinuity may be detected, there will not be a back surface reflection in the situation above.
> Selection of the proper transducer is very important in obtaining a good ultrasonic test.
> As shown below, a transducer with a plastic wedge may be necessary to look into a specimen at an angle.
TRANSDUCER A FRONT REFLECTION
PLASTIC G vn REFLECTION
STEEL
SPECIMEN
> Selection of the proper transducer is very important in obtaining a good ultrasonic test.
> As shown below, a transducer with a plastic wedge may be necessary to look into a specimen at an angle.
TRANSDUCER A FRONT REFLECTION
PLASTIC G vn REFLECTION
STEEL
SPECIMEN
> The pulse length used will affect the ability of the instrument to locate discontinuities near the surface as shown below.
> A longer pulse may block the receiver during the period of transmission and obscure reflections from the
discontinuity. The transducer may continue vibrating beyond the time the discontinuity energy is received.
HIGH PULSE
LENGTH
LONG PULSE
DISCONTINUITY TEST SPECIMEN
DISCONTINUITY
SHORT PULSE
> In angle beam contact testing, the transducer is placed behind a wedge, usually lucite, so that the sound will be
introduced into the part at an angle.
> As shown below, the angle of incidence of the sound beam at the surface is determined by the fixed angle of the
wedge.
> A longer pulse may block the receiver during the period of transmission and obscure reflections from the
discontinuity. The transducer may continue vibrating beyond the time the discontinuity energy is received.
HIGH PULSE
LENGTH
LONG PULSE
DISCONTINUITY TEST SPECIMEN
DISCONTINUITY
SHORT PULSE
> In angle beam contact testing, the transducer is placed behind a wedge, usually lucite, so that the sound will be
introduced into the part at an angle.
> As shown below, the angle of incidence of the sound beam at the surface is determined by the fixed angle of the
wedge.
ANGLE OF INCIDENCE— $
Ar
N
ANGLE OF WEDGE BLOCK
TRANSDUCER
TEST SPECIMEN
SOUND ANGLE IN SPECIMEN (REFRACTED ANGLE)
> As discussed previously, the sound beam angle in a test part is determined by the relationship of the velocity of
sound in the test specimen and the velocity of sound in the wedge. This relationship is known as "snell's law."
> As shown below, when the angle of incidence increases, refraction of the longitudinal wave increases until
there comes a point where total reflection of this wave occurs, and all that is left is a shear wave.
> This point is called the 1st critical angle of incidence.
Ar
N
ANGLE OF WEDGE BLOCK
TRANSDUCER
TEST SPECIMEN
SOUND ANGLE IN SPECIMEN (REFRACTED ANGLE)
> As discussed previously, the sound beam angle in a test part is determined by the relationship of the velocity of
sound in the test specimen and the velocity of sound in the wedge. This relationship is known as "snell's law."
> As shown below, when the angle of incidence increases, refraction of the longitudinal wave increases until
there comes a point where total reflection of this wave occurs, and all that is left is a shear wave.
> This point is called the 1st critical angle of incidence.
MEDIUM 1
MEDIUM 2
> To produce a sound beam at a given angle, it is necessary to know only the following three factors to
determine the proper wedge angle:
1.The angle desired in the test specimen.
2. The longitudinal velocity in the wedge.
3. The velocity in the test material. (Shear or longitudinal, depending on the sound beam desired)
> In angle beam testing, the angle of refraction becomes less as the velocities of sound in the wedge and test
specimen become more nearly equal.
MEDIUM 2
> To produce a sound beam at a given angle, it is necessary to know only the following three factors to
determine the proper wedge angle:
1.The angle desired in the test specimen.
2. The longitudinal velocity in the wedge.
3. The velocity in the test material. (Shear or longitudinal, depending on the sound beam desired)
> In angle beam testing, the angle of refraction becomes less as the velocities of sound in the wedge and test
specimen become more nearly equal.
> Only longitudinal waves will be produced in the wedge, but it is possible to have either longitudinal or shear
waves in the test part.
> Both modes may be present at the same time depending on the angle of the wedge.
> The following charts show the relative angle and amplitude for both longitudinal and shear waves in steel for
given wedge angles in lucite.
> When choosing a wedge, it is desirable to avoid angles that produce both longitudinal and shear waves at the
same time and at similar intensities.
> The presence of both waves makes it difficult to interpret the CRT screen which displays both reflections.
RELATIVE
AMPLITUDE
I
SURFACE
+
60 65 70 75 80
ANGLE 60
OF SOUND so
IN STEEL
(DEGREES)
o 3 10 15
20
25 30 35 40
45 50 55 60 65 70 75 80
ANGLE OF TRANSDUCER WEDGE BLOCK (DEGREES) IN LUCITE
waves in the test part.
> Both modes may be present at the same time depending on the angle of the wedge.
> The following charts show the relative angle and amplitude for both longitudinal and shear waves in steel for
given wedge angles in lucite.
> When choosing a wedge, it is desirable to avoid angles that produce both longitudinal and shear waves at the
same time and at similar intensities.
> The presence of both waves makes it difficult to interpret the CRT screen which displays both reflections.
RELATIVE
AMPLITUDE
I
SURFACE
+
60 65 70 75 80
ANGLE 60
OF SOUND so
IN STEEL
(DEGREES)
o 3 10 15
20
25 30 35 40
45 50 55 60 65 70 75 80
ANGLE OF TRANSDUCER WEDGE BLOCK (DEGREES) IN LUCITE
Q Example:
1. Assume that you have a lucite wedge with an angle of 50 degrees, referring to the chart above, what angle shear
waves will be produced in the test specimen?
2. What problem would be encountered using a 50 degree longitudinal wave?
(#1 = about 65 degrees) (#2 = shear wave also exists)
> In angle beam testing, when the wedge angle is increased to the point that the shear wave is equal to 90
degrees, we have what is known as the 2nd critical angle.
> However, sound energy still exists parallel to the interface and is known as "surface waves" or "rayleigh waves"
as discussed previously.
INCIDENT BEAM (vn. A sind, sind,
v - Tu
SA 1 2
X
MEDIUM 1
MEDIUM 2
REFRACTED BEAM (SHEAR) (V,)
1. Assume that you have a lucite wedge with an angle of 50 degrees, referring to the chart above, what angle shear
waves will be produced in the test specimen?
2. What problem would be encountered using a 50 degree longitudinal wave?
(#1 = about 65 degrees) (#2 = shear wave also exists)
> In angle beam testing, when the wedge angle is increased to the point that the shear wave is equal to 90
degrees, we have what is known as the 2nd critical angle.
> However, sound energy still exists parallel to the interface and is known as "surface waves" or "rayleigh waves"
as discussed previously.
INCIDENT BEAM (vn. A sind, sind,
v - Tu
SA 1 2
X
MEDIUM 1
MEDIUM 2
REFRACTED BEAM (SHEAR) (V,)
> As shown on the chart on the previous page, a wedge angle of 63 degrees will produce surface waves of the
greatest amplitude in steel.
> As shown below, the surface wave penetrates only one wave length below the surface and has the ability to
follow the part
> Contour. Any sharp angle on the surface will cause a reflection.
TRANSDUCER DISCONTINUITY
TEST SPECIMEN
greatest amplitude in steel.
> As shown below, the surface wave penetrates only one wave length below the surface and has the ability to
follow the part
> Contour. Any sharp angle on the surface will cause a reflection.
TRANSDUCER DISCONTINUITY
TEST SPECIMEN
ULTRASONIC-TESTING
METHOD LEVEL Ihé. III
APPLICATIONS OF ANGLE BEAM
CONTACT TESTING.
METHOD LEVEL Ihé. III
APPLICATIONS OF ANGLE BEAM
CONTACT TESTING.
Course Contains
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
. Ultrasonic Transducers And Standard Reference Blocks.
PO N DAH PF WN PB
|. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell's Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
. Application, Training & Certification.
. Ultrasonic Principles.
. Ultrasonic Testing Methods & Equipment Controls.
. Wave propagation, Reflection & Refraction.
. Couplant , Ultrasonic Sound Energy & Materials Characteristics
. Attenuation, Acoustic Impedance, And Resonance.
. Displaying Ultrasonic Indications & Angle Beam Inspection with calculation
. Ultrasonic Transducers And Standard Reference Blocks.
PO N DAH PF WN PB
|. Immersion Inspection.
10. Ultrasonic Contact Testing and Shell's Law
11. Applications Of Angle Beam Contact Testing.
12. Nonrelevant Ultrasonic Indications.
13. Discontinuities, Their Origin And Types.
SERVICES
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya ij sono rs
https://www. linkedin.com/in/vishal-dhameliya-07605a4a/ M METHOD Lever. 1 & 111 ||
APPLICATIONS OF ANQ EN)
>
A,
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
SERVICES
> YouTube Channel -- WELDING KNOWLEDGE
https://www.youtube.com/channel/UCIUgZeXcvTVaiRmQinloCxQ
> LinkedIn :- Vishal Dhameliya ij sono rs
https://www. linkedin.com/in/vishal-dhameliya-07605a4a/ M METHOD Lever. 1 & 111 ||
APPLICATIONS OF ANQ EN)
>
A,
> Dipesh Patel - +91 8155079565
> Vishal Dhameliya :- +91 9737177783
52
.
> Applications of contact testing
> The lower range of frequencies are generally used to test castings since castings usually have a rather coarse
grain structure.
> Many ofthe very coarse grained castings cannot be tested with ultrasonics.
> Most forgings are good objects for ultrasonic testing. Common discontinuities found in forgings are shown
INITIAL PULSE BACK REFLECTION
Ia A
NONMETALLIC SEAM CRACK FLAKING
INCLUSION
.
> Applications of contact testing
> The lower range of frequencies are generally used to test castings since castings usually have a rather coarse
grain structure.
> Many ofthe very coarse grained castings cannot be tested with ultrasonics.
> Most forgings are good objects for ultrasonic testing. Common discontinuities found in forgings are shown
INITIAL PULSE BACK REFLECTION
Ia A
NONMETALLIC SEAM CRACK FLAKING
INCLUSION
> Discontinuities in a forging are most likely to be detected if the inspection is made at right angles to the direction that
the material was worked. Working will orient discontinuities in the same direction as the grain of the metal is oriented.
> Rolled sheet and plate materials may be tested with either a straight beam or angle beam, depending on the
specification requirements.
> Straight beam testing has the advantage of being able to easily locate laminations.
> However, straight beam testing is time consuming and may not "see" discontinuities close to the surface, unless
special techniques are used.
> The advantage of angle beam testing is that it is a very fast method of inspecting plate materials.
> Most types of discontinuities found in plate that are perpendicular to the scan surface will be found with angle
beam testing.
> However, smooth laminations parallel to the surface well probably not be detected by angle beam testing.
TRANSDUCER
the material was worked. Working will orient discontinuities in the same direction as the grain of the metal is oriented.
> Rolled sheet and plate materials may be tested with either a straight beam or angle beam, depending on the
specification requirements.
> Straight beam testing has the advantage of being able to easily locate laminations.
> However, straight beam testing is time consuming and may not "see" discontinuities close to the surface, unless
special techniques are used.
> The advantage of angle beam testing is that it is a very fast method of inspecting plate materials.
> Most types of discontinuities found in plate that are perpendicular to the scan surface will be found with angle
beam testing.
> However, smooth laminations parallel to the surface well probably not be detected by angle beam testing.
TRANSDUCER
> Before performing an angle beam test, the plate should be scanned with a straight beam transducer to find any
gross defects or laminations.
> When an angle test is performed on plate, it is common to establish a "reference" so that the amplitude of a
discontinuity can be compared to a known size reflector. The following procedure explains one way this can be
done:
1. Set up a "reference notch" which is either 3% of the part thickness or 0.005" deep.
2. Place the transducer so that a signal from the notch is obtained on the first leg and adjust gain so that
the signal is 1000/0 screen height.
3. Move the transducer back so that a signal from the notch is obtained on the second leg and mark the
signal height on the CRT with a grease pencil. Repeat this step at longer specific distances.
4, When a discontinuity is found, move the transducer to one of the known distances and compare
amplitude of discontinuity with notch.
5. The plate should then be scanned along each of the plates four edges. Discontinuities missed in one
scan, should be picked up in another direction.
> Contact testing of weldments can be accomplished by either straight beam or angle beam techniques, based on
the type of defect to be detected.
> Straight beam testing requires that the surface of ti4e weld be ground smooth as shown below. However, lack of
fusion, cracks, insufficient penetration are not easily detected with straight beam techniques.
gross defects or laminations.
> When an angle test is performed on plate, it is common to establish a "reference" so that the amplitude of a
discontinuity can be compared to a known size reflector. The following procedure explains one way this can be
done:
1. Set up a "reference notch" which is either 3% of the part thickness or 0.005" deep.
2. Place the transducer so that a signal from the notch is obtained on the first leg and adjust gain so that
the signal is 1000/0 screen height.
3. Move the transducer back so that a signal from the notch is obtained on the second leg and mark the
signal height on the CRT with a grease pencil. Repeat this step at longer specific distances.
4, When a discontinuity is found, move the transducer to one of the known distances and compare
amplitude of discontinuity with notch.
5. The plate should then be scanned along each of the plates four edges. Discontinuities missed in one
scan, should be picked up in another direction.
> Contact testing of weldments can be accomplished by either straight beam or angle beam techniques, based on
the type of defect to be detected.
> Straight beam testing requires that the surface of ti4e weld be ground smooth as shown below. However, lack of
fusion, cracks, insufficient penetration are not easily detected with straight beam techniques.
VIEW À
> Angle beam testing of weldments is done as shown in view "b" above.
> To scan the welded seam, it is necessary to move the transducer forward and backward as shown below.
> At 1/2 skip distance, the beam strikes the bottom of jue e and dat 1 skip distance, the beam will strike the top
of the plate as shown. 4
A
SKIP
DISTANCE
> Angle beam testing of weldments is done as shown in view "b" above.
> To scan the welded seam, it is necessary to move the transducer forward and backward as shown below.
> At 1/2 skip distance, the beam strikes the bottom of jue e and dat 1 skip distance, the beam will strike the top
of the plate as shown. 4
A
SKIP
DISTANCE
> Skip distance is determined by the angle of the sound entering the weldment, which is determined by the lucite
wedge angle.
> Once the skip distance is known, a chalk mark can be made on the part to show where the transducer must be
moved for complete coverage of the weld zone.
> Beam angle selection is determined by:
> 1. Code or procedure requirements
> 2. Weld joint design
> 3. Specimen configuration
> The following table shows examples of favorable beam angles for testing welds in materials of varying thickness.
> As sheet thickness increases, beam angle should be decreased.
WELD BEAD GROUND ON BOTH SIDES
SHEET THICKNESS BEAM ANGLE SKIP DISTANCE
(INCHES) (DEGREES) (INCHES)
0.2-0.6 2.2-6.6
6 -2-6.6
-2 8.4
VE ‘Le
VER .8 AND UP
wedge angle.
> Once the skip distance is known, a chalk mark can be made on the part to show where the transducer must be
moved for complete coverage of the weld zone.
> Beam angle selection is determined by:
> 1. Code or procedure requirements
> 2. Weld joint design
> 3. Specimen configuration
> The following table shows examples of favorable beam angles for testing welds in materials of varying thickness.
> As sheet thickness increases, beam angle should be decreased.
WELD BEAD GROUND ON BOTH SIDES
SHEET THICKNESS BEAM ANGLE SKIP DISTANCE
(INCHES) (DEGREES) (INCHES)
0.2-0.6 2.2-6.6
6 -2-6.6
-2 8.4
VE ‘Le
VER .8 AND UP
Q Example:
> The surface distance to a point directly above the discontinuity can be calculated according to the formula:
D=Sx (SIND “D" = SURFACE DISTANCE
piscontinuity “S" = SOUND PATH DISTANCE
FA» '()” = REFRACTED SOUND BEAM ANGLE
Q Example:
> With a properly calibrated 70 degree probe, what is the distance "d" from the exit point of the probe to the
discontinuity? Distance "s" shows on the CRT at 4.6" (do not consider the sound travel in the lucite wedge).
> Sxsin d= .939 multiplyed by sound path of 4.6" equals a surface distance "d" of 4.332 inches
> The surface distance to a point directly above the discontinuity can be calculated according to the formula:
D=Sx (SIND “D" = SURFACE DISTANCE
piscontinuity “S" = SOUND PATH DISTANCE
FA» '()” = REFRACTED SOUND BEAM ANGLE
Q Example:
> With a properly calibrated 70 degree probe, what is the distance "d" from the exit point of the probe to the
discontinuity? Distance "s" shows on the CRT at 4.6" (do not consider the sound travel in the lucite wedge).
> Sxsin d= .939 multiplyed by sound path of 4.6" equals a surface distance "d" of 4.332 inches
> It is usually necessary to know the "skip distance" of the sound beam in a part with any given angle transducer.
> Skip distance can be found by using the following formula:
P = SKIP DISTANCE
ANGLE OF SOUND IN PART
PLATE THICKNESS
e
1
P=2xTANOxT
TAN
4
I
mee | SKIP DISTANCE 8 |
p
DEXAMPLE: WHAT IS THE SKIP DISTANCE ON A 3/8 INCH PLATE WITH A 70 DEGREE TRANSDUCER?
+ P=2(TANO) xT
+ P= 2.06 INCHES
> Skip distance can be found by using the following formula:
P = SKIP DISTANCE
ANGLE OF SOUND IN PART
PLATE THICKNESS
e
1
P=2xTANOxT
TAN
4
I
mee | SKIP DISTANCE 8 |
p
DEXAMPLE: WHAT IS THE SKIP DISTANCE ON A 3/8 INCH PLATE WITH A 70 DEGREE TRANSDUCER?
+ P=2(TANO) xT
+ P= 2.06 INCHES
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