Presentation on Piping Familiarization.ppt

All about PIping

1. SABIC Engineering & Project Management
Presentation
on
PIPING FAMILIARIZATION
•Piping Essentials
•Project Support
•Affiliate Technical Support
Contents

2. •Piping is one of the most talked
about but least understood of
subjects.
•Piping designers out number all
other design specialists on a project.
•Most laymen think of piping as a
hollow cylindrical piece of metal or
non-metal. That is a pipe, not piping.
•The term “PIPING” refers to the
overall network of pipes, fittings,
flanges, valves, supports, and other
components that comprise a
complete system used to convey
fluids (liquids, vapors, or gas).
PIPING OVERVIEW

3. Piping is governed by the following codes :
•ASME B31.1 for power plant piping.
•ASME B31.3 for chemical process plant piping.
•ASME B31.4 for oil pipelines.
•ASME B31.5 for refrigeration piping.
•ASME B31.8 for gas pipelines.
•ASME B31.9 for gas, steam and water piping.
•ASME B31.11 for slurry transportation piping.
•AWWA for water works piping.
•NFPA-13 and -24 for fire protection systems
•Each code has different set of rules & allowable
limits
•Use of appropriate code for safe & economic
design .
•Wrong selection of the code can cost the
project several extra million riyals .
STANDARDS
•Contain design and
construction rules for piping
components.
•Compliance to standards is
the owner’s prerogative.
CODES
•Set forth minimum mandatory
requirements for design,
material, fabrication, erection,
test and inspection of the
piping system.
•The ASME develops codes for
pressure piping.
•The first edition of code for
pressure piping was published
in 1935 under the ANSI
committee which later changed
to ASME
PIPING OVERVIEW

4. SES in Piping are categorized into five parts:
•Design standards ------------( 30 SES)
•Material specifications --------(75 SES)
•Construction requirements ------(3 SES)
•Inspection requirements --------(3 SES)
•Selection of component --------(30 SES)
Sabic has one of the most comprehensive set of piping standards
compared to Aramco, Exxon, Mobil, Shell or any other world class
organization.
SABIC ENGINEERING STANDARDS

5. PIPE
•A pipe is a tube with a round cross section having an outside
diameter(O.D) and an inside diameter(I.D).
•The Outside diameter does not vary with the wall thickness.
•Pipe is specified in nominal pipe size(NPS).
•For sizes <12” the NPS does not match the pipe OD.
•For sizes >14” the NPS is the OD.
•Pipe is manufactured as :
•Seamless :
•Expensive
•Without any longitudinal seam.
•Joint efficiency factor of 100% as there are no welds in the pipe.
•Spiral welded,
•Electric Resistance Welded,
•Submerged Arc Welded etc.
•Spiral welded or ERW pipe is made by the electric fusion welded
process from flat steel sheets with a spiral or longitudinal joint. Welded
pipe has reduced joint efficiency.

6. PIPE . . . . . Contd.
•Pipe is supplied from the mill in
random (20ft) or double random
(40ft.) lengths with beveled ends.
•A pipe is acceptable if the
nominal thickness minus the mill
tolerance equals or exceeds the
minimum wall thickness.
•SES are based on the latest
edition of ASME B31.3 code
criteria and take into consideration
the change in factor of safety.
The minimum thickness equals the
pressure design thickness plus
corrosion and other allowances.

7. FITTINGS
•Fittings include elbows, tees, reducers, branch
connections and integrally reinforced connections.
•Fittings in sizes 3” and above are wrought steel butt
welding in accordance with ASME B16.9.
•Fittings in sizes 2” and less are socket welded or
threaded in accordance with ASME B16.11.
•Threaded fittings are used in low pressure steam,
condensate and utility services whereas in critical
services socket welded are the fittings of choice.

8. FLANGES
•A joint in a piping system is achieved by 1)
welding 2)threading and 3) flanges.
•Flange is required at spec/class break -
Governed by ASME B 16.5.
•A flanged joint is composed of three
independent and separate components: the
flanges, the gaskets, and the bolting.
•Flanges come in seven pressure ratings:
150, 300, 400, 600, 900, 1500, and 2500#.
•Flanges differ in the method of attachment
to the pipe. They are welded (welding neck or
socket welded), slip-on, screwed, lapped,
blind, threaded, or orifice.
•Orifice flanges have an orifice tapped into
the flange body and are used for flow
measurement. Orifice flanges come in 300#
minimum rating.
Typical Flange Assembly
Weld NeckSlip-onOrifice

9. FLANGES . . . . .Contd.
•Flange facings-raised face, flat face, or the ring joint. Ring joint
facings are utilized only in high pressures over 900#.
•To specify a flange, we need the material, rating, type and the
facing.E.g.; 300#,CS, WN RF would mean a carbon steel weld-neck
flange of 300# pressure rating with raised face.
•Resilient material
•Inserted between flanges
•Compressed by bolts to create seal
•Commonly used types :
Sheet, Spiral wound, Solid metal ring
GASKETS

10. VALVES
•Gate valve: On-Off service, good
pressure retaining characteristics
•Globe valve: Used for throttling
•Check: To prevent back flow-normally
flanged
•Ball: Used for On-Off and Throttling-
1/4(90-deg.) turn for on-off positioin
•Control: Four functions-control
pressure, flow, level, temperature
•Butterfly: Economical –fits between two
flanges-used in water systems

11. STRESS / FLEXIBILITY ANALYSIS
Why do we perform Pipe stress analysis?
•To keep stresses within the code allowable limits
•To keep nozzle loadings on equipment within manufacturer’s or code
allowable (API 610,API617,Nema SM 23 etc.)
•To keep vessel stresses at nozzles within ASME SEC.V111 allowable
•To calculate design loads on supports and structures
•To determine piping displacements for interference check
•To solve dynamic problems such as those due to
•Harmonic/Cyclic loading in mechanical or acoustic
vibrations/pulsations
•Impulse loading in fluid hammer, transient flow, relief valve
discharge
•Random loadings as in earthquake or wind

12. STRESS / FLEXIBILITY ANALYSIS
What is primary stress and secondary stress?
•Primary stress:normal or shear stress due to imposed loading such as
pressure and sustained loads. Could cause permanent deformation and
failure of the piping system.
•Code equation for condition equilibrium:
S
L= S
L1+ S
L2
S
L= (P x D / 4 x t) + (M
A/ Z) < 1.0 S
h
•Secondary stress:Normal or shear stress caused when a system's
flexibility is constrained as due to thermal loads. Failure will not occur
and local yielding or distortion can satisfy this condition.
P = Internal design pressure
D = outside diameter of pipe
t = pressure design thickness
M
A= resultant moment loading
due to weight and sustained
loads
Z = section modulus
S
h= basic allowable stress at
maximum metal temperature.

13. STRESS / FLEXIBILITY ANALYSIS
Code equation for condition equilibrium:
S
E< S
A
S
E< (S
b2+ 4 S
t2)
1\2
P = S
A= f (1.25 S
c+ 0.25 S
h)
S
b= i M
b/ Z (Resultant bending stress due to thermal expansion)
S
t= M
t/ 2Z (Torsional stress due to thermal expansion)
M
b= Resultant bending moment due to thermal restraint
M
t= Torsional moment due to the thermal restraint
i = Stress intensification factor (SIF).
z = Section modulus of pipe
S
c= Basic allowable stress at minimum metal temperature.
S
h= Basic allowable stress at maximum metal temperature.
f = Stress range reduction factor for cyclic conditions., 1.0 for 7000 Cycles

14. PIPE SUPPORTS
•Good pipe support design begins with good piping design layout.
•Pipe support specifications for projects must assure proper slope,
expansion, anchorage, and insulation protection.
•The dollar value of the support system generally outweighs the value of
pipe, valves, and fittings -a bad support system can lead to costly erection
delays.
•Hangers and supports must be designed to meet all
static and dynamic loads.
•Supports are categorized into two main types.
•Rigid supports
•Spring supports.

15. Restraints
•Control, limit, redirect thermal
movement
•Reduce thermal stress
•Reduce loads on equipment
connections
•Absorb imposed loads
•Wind
•Earthquake
•Slug flow
•Water hammer
•Flow induced-vibration
RESTRAINTS -Anchors and Guides
Restraint Selection
•Direction of pipe movement
•Location of restraint point
•Magnitude of load
Anchor
•Full fixation
•Permits very limited (if any)
translation or rotation
Guide
•Permits movement along
pipe axis
•Prevents lateral movement
•May permit pipe rotation

16. PIPING SUPPORTS
Rigid Restraints
Rigid Hangers
Anchors &
Guides
Spring Supports

17. PROJECT REVIEW -COST SAVING AND VALUE ADDING
MATERIALS
Pipeline approach
•Quantity of pipe in pipelines is far greater than the amount of fittings &
valves
•Minimizing of the pipe wall is the major economic factor.
•Pipe Thickness aCost: E.g., doubling the pipe wall roughly doubles
the price.
•Pipe is purchased by weight: Premium for high strength material is off-
set by lower pipe wall.
•The material of choice for most Contractors is API-5L SEAMLESS, GR.B.
•ERW pipe meeting certain design requirements is almost 40 percent
cheaper
•X grades of pipe should be specified instead of GR. B for wall thickness
above 0.25”
•Cost savings of X-grade pipe Vs grade B

18. PROJECT REVIEW
Grade of Required Approx. % savings due
Pipe Wall thk. to wall thickness reduction
Grade B 0.25-0.29 0
X-42 0.30-0.37 20
X-52 0.38-0.43 30
X-60 >0.44 35
Pipe wall thickness Vs. Cost

19. PROJECT REVIEW
Plant Approach
•Emphasis is on standardized material.
•The relative cost of pipe is small compared to the cost of fittings and
valves
•Price vs. availability is of prime concern
E.g. Type 304 SS costs less than type 316. Many valve manufacturers
standardize on type 316, as it is suitable for both. A project I worked in
Alabama was delayed by four weeks because the client had insisted
on type 304. Cost saved at the expense of extended delivery time
•Selection & application of appropriate code jurisdiction is another key
factor.
•In general, for lower grade materials, ASME B31.3 gives higher
allowable thermal expansion stress in comparison to ASME B31.4
•ASME B31.3 allows higher surge pressure and is conservative in
PWHT requirements

20. PROJECT REVIEW
Quick way to select pipe :
The idea is to purchase the highest ‘S’ per ‘Riyal’ rating.
•SABIC has developed piping material class adopted from PIP (Process
Industry practices)
•When the material is expensive, large savings can be realized by
specifying pipe made from plate with 100% radiography.
•The Mill Tolerance : Seamless pipe 12.5 % ; Welded pipe 0.01”
•Types 304 or 316 SS are advisable to be used only for corrosion
resistance.
-Expensive & not suitable to Saudi Arabian environmental
conditions.
•Subject to pitting in chloride bearing waters & cause Stress
corrosion cracking. Require water low in chlorides for hydro testing.
Allowable Stress at each temperature
Relative Cost

21. PRESSURE TESTING –A Case Study
•A LSTK Contractor specified that pressure testing will be done in
accordance with ASME B31.3 code criteria.
•For most companies this is acceptable as B31.3 is the encyclopedia for
process piping.
•B31.3 lays down the rules for pressure testing, the magnitude and
strength of the test, and the test duration etc.
•What the clients failed to notice that B31.3 does not mention about a
set of activities that needs to be done both before and after the test.
•Such activities include Connection & re-connection of Components. All
temporary items required for testing purposes (e.g., manifolds, valves,
blinds, spacers, supports) shall be provided & items that were removed
from testing shall be reinstalled.
•If this were not spelled out in the contractor’s scope of work, then the
client would end up paying un-necessary extra cost thaat could run into
millions for large number of piping segments.

22. BLOCK AND BY-PASS VALVES
•LSTK contractors do not like block and by-pass valves as these denote high
dollars.
•Bypass valves
•On-stream testing of the shutdown valve (for tight shut-off)
•For depressurizing downstream process piping & equipment in a
gradual manner.
•Equalizing valves around EIVs are recommended to have limit switches
& valve position (open/close) stem indicators for remote indication of
valve position.
IEC requires that the Safety integrity level testing of emergency isolation
valves shall be done on-stream and not wait for turn-arounds.
•Block valves
•Not needed for power operated normally open Emergency Isolation
Valves (EIV) which are (e.g., isolation valves around process equipment)
since they can be bumped or partially closed during on-stream testing.
•Recommended on upstream side for power operated normally closed
EIVs which are (e.g., vapor de-pressuring downs) to permit on-stream
testing, unless determined otherwise on a case-by-case basis.

23. BURIED LINES AND CORROSION PROTECTION REQUIREMENTS
•Scope for cathodic protection of buried lines must be clearly defined :
Contractors may get away by providing coating alone & Companies end
up paying huge extra costs
•All buried pipelines and structures including buried valves, thrust
anchors, need to be protected against corrosion by
•External coating
•Cathodic protection with impressed current systems.
•Integrated cathodic protection system required, irrespective of the type
of coating on new / existing pipelines.
•For cross-country pipelines, cathodic protection is achieved within 30
days of pipeline burial.
•For other pipelines, cathodic protection is achieved within 7 days of
pipeline burial.
•Minimum design life of impressed current systems is generally 20 years.
•Minimum design life of galvanic anode systems is generally 20 years.

24. BOLTS ON FLANGES
Bolts on Flanges
•Though it sounds simple, but could cause costly delays on the project
•Bolt holes are placed in a circle on the flange known as the bolt hole
circle(BHC).
•Bolts should straddle the centerlines of the bolt circle as a general
design practice.
A Case Study
•A project by Parsons for QGPC
•Pressure vessel manufactured in Korea
•The Pressure vessel nozzle flange & mating flange was purchased
from Italy.
•The Italian manufacturer placed the bolts on the centerline instead of
straddling it.
…………..Rest is history !

25. TECHNICAL SUPPORT TO AFFFILIATES
•Sabic’s Affiliates have experienced severe damage to piping
and supporting structures due to inadequate design for
thermal, sustained and dynamic loads.
•Advanced stress analysis will eliminate 80% of the safety
hazards and failures in the piping system.
•Many of the problems referred to us are because of poor or
no stress analysis during the design phase.
•This is costing the Affiliates several million riyals in
engineering man-hours and costly retrofits.

26. TECHNICAL SUPPORT TO AFFFILIATES
Technical Support to Affiliates:
•IBN ZAHR
•KEMYA
•ARRAZI
•IBN BAYTAR
•GAS
•HADEED
•SHARQ

27. TECHNICAL SUPPORT TO AFFFILIATES
IBN ZAHR
•To evaluate Root cause for the failure of “TEE” joints on the
72” main Reactor MTBE Piping & provide recommendations to
prevent recurrence of crack propagation
•Increase the throughput of MTBE from the present 4,400 M
tons Per day to higher output.
•Increase in feed rate of Iso-butane in Catofin1from current
104MT/hr to 10 MT/Hr in view of the potential business of
Isobutylene and MTBE.
•Design checks to verify the mechanical integrity of Piping,
pumps, compressors, reactors arches, heat exchangers,
distributors, compressors, columns, and heaters capacities etc
verification were to be carried out.

28. TECHNICAL SUPPORT TO AFFFILIATES
KEMYA :
•Vibration Analysis for Chilled water and Cooling Water
Piping
•Fluid hammer, Thermal & Dynamic stress analysis of Hot
water Pipeline.
•Pipeline 6'' SS ( 08-1713ARSW-6'' ) bypass hot water
pipeline to EXTD-0801B-B was distorted and damaged
at two support guide locations.
•Analysis of root cause and recommend necessary
alterations required to prevent future occurrence of
such deformation / damage.

29. TECHNICAL SUPPORT TO AFFFILIATES
KEMYA
Hot Water Piping
Fluid Transient /
Dynamic Analysis

30. TECHNICAL SUPPORT TO AFFFILIATES
KEMYA –Hot Water Pelletizer Piping
Fluid Transient / Dynamic Analysis