Structural Welding.pptx

This presentation is intended to give a clear guidance to the reader on AWS D1.1. That is on Structural Welding and its legitimacy in the industry. This would be more helpful for MEP engineers and well as Structural engineers in practice. More over, those who are in the process of learning could be benefited using this.

1. Structural Welding and AWS D1.1; 2020 IntPE M.A.S. Upul Kumara , BScEng ( LK ), PGDipEPCEng (LK), MSc ( MY), IntPE , CEng, FIE(SL) CPEngNZ , MAWS (USA), MASME(USA), PM-ASNT(USA ),SNT-TC-1A- Lev II NDT Inspector [phone] kumar.msu906.gmail.com

2. Welding is a never ending process welding positions

3. Flat (1g, 1F) Position

4. Horizontal position (2g, 2F)

5. Vertical positions (3G, 3F)

6. Overhead position (4g, 4F)

7. Types of welding joints 1. Butt weld the butt joint uses the following preparation styles. Bevel-Groove Butt Weld Flare-Bevel-Groove Butt Weld Flare-V-Groove Butt Weld J-Groove Butt Weld Square-Groove Butt Weld U-Groove Butt Weld V-Groove Butt Weld

8. 2. Corner welding joint The styles employed are as follows. Bevel-Groove Weld Corner-Flange Weld Edge Weld Fillet Weld Flare-V-Groove Weld J-Groove Weld Spot-Weld Square-Groove Weld or Butt Weld U-Groove Weld V-Groove Weld Types of welding joints

9. Types of Welding Joints 3. Lap welding joints Welding Style for Lap Joint Bevel-Groove Weld Flare-Bevel-Groove Weld J-Groove Weld Plug Weld Slot Weld Spot-Weld

10. 4. Tee Joint Welding Style for Tee Joint Bevel-Groove Weld Fillet Weld Flare-Bevel-Groove Weld J-Groove Weld Melt-Through Weld Plug Weld Slot Weld Types of Welding Joints

11. 5. Edge welding Joints Joint creation takes place using the following styles . Bevel-Groove Weld Corner-Flange Weld Edge-Flange Weld J-Groove Weld Square-Groove Weld or Butt Weld U-Groove Weld V-Groove Weld Types of Welding Joints

12. The following are some of the most used welding types in the industry. 1. Gas Metal Arc Welding ( GMAW ) – MIG 2. Gas Tungsten Arc Welding ( GTAW ) – TIG 3. Flux Cored Arc Welding ( FCAW ) 4. Shielded Metal Arc Welding ( SMAW ) – Stick 5. Atomic Hydrogen Welding ( AHW ) 6. Energy Beam Welding ( EBW ) 7. Underwater Welding Types of Welding Processes

13. Welding processes SMAW GMAW GTAW SAW FCAW

14. Based on AWS D1.1;2020 Version Code comprised of following sections Section 1. General Requirements Section 2. Normative References Section 3. Terms and Definitions Section 4. Design of welded connections Section 5. Prequalification of WPS Section 6. Qualification Section 7. Fabrication Section 8. Inspection Section 9. Stud welding Section 10. Tubular Structures Section 11. Strengthening and Repair of Existing structures

15. Section 1. General Requirements 1.1 Scope This code contains the requirements for fabricating and erecting welded steel structures. When this code is stipulated in contract documents, conformance with all provisions of the code shall be required, except for those provisions that the Engineer or contract documents specifically modifies or exempts .

16. Section 1. General Requirements 1.2 Standard Unit of Measurements This standard makes use of both U.S. Customary Units and the International System of Units (SI). The latter are shown within brackets ([ ]) or in appropriate columns in tables and figures. The measurements may not be exact equivalents; therefore, each system must be used independently.

17. Section 1. General Requirements 1.3 Safety Precautions Safety and health issues and concerns are beyond the scope of this standard and therefore are not fully addressed herein. It is the responsibility of the user to establish appropriate safety and health practices. Safety and health information is available from the following sources: American Welding Society: ( 1) ANSI Z49.1, Safety in Welding, Cutting, and Allied Processes ( 2) A WS Safety and Health Fact Sheets ( 3) Other safety and health information on the A WS website Material or Equipment Manufacturers: ( 1) Safety Data Sheets supplied by materials manufacturers ( 2) Operating Manuals supplied by equipment manufacturers Applicable Regulatory Agencies

18. Section 1. General Requirements 1.4 Limitations The code was specifically developed for welded steel structures that utilize carbon or low alloy steels that are 1/8 in [3 mm] or thicker with a minimum specified yield strength of 100 ksi [690 MPa] or less. The code may be suitable to govern structural fabrications outside the scope of the intended purpose. However , the Engineer should evaluate such suitability, and based upon such evaluations, incorporate into contract documents any necessary changes to code requirements to address the specific requirements of the application that is outside the scope of the code. The Structural Welding Committee encourages the Engineer to consider the applicability of other AWS DI codes for applications involving aluminum (AWS D l.2 ), sheet steel equal to or less than 3/16 in [5 mm] thick (AWS D l.3 ), reinforcing steel (AWS D l.4 ), stainless steel (AWS D l.6 ), strengthening and repair of existing structures (AWS D l.7 ), seismic supplement (AWS D l.8 ), and titanium (AWS D l.9 ). The AASHTO/AWS D l.5 Bridge Welding Code was specifically developed for welding highway bridge components and is recommended for those applications.

19. Section 1. General Requirements 1.5 Responsibilities 1.5.1. Engineers Responsibility The Engineer shall be responsible for the development of the contract documents that govern products or structural assemblies produced under this code. The Engineer may add to, delete from, or otherwise modify, the requirements of this code to meet the particular requirements of a specific structure. All requirements that modify this code shall be incorporated into contract documents. The Engineer shall determine the suitability of all joint details to be used in a welded assembly. The Engineer shall specify in contract documents, as necessary, and as applicable, the following: ( 1) Code requirements that are applicable only when specified by the Engineer. ( 2) All additional NDT that is not specifically addressed in the code. ( 3) Extent of verification inspection, when required. ( 4) Weld acceptance criteria other than that specified in Clause .8_. ( 5) CVN toughness criteria for weld metal, base metal, and/or RAZ when required. ( 6) For nontubular applications, whether the structure is statically or cyclically loaded.

20. Section 1. General Requirements 1.5 Responsibilities (7J Which welded joints are loaded in tension. (8) All additional requirements that are not specifically addressed in the code. (9) For OEM applications, the responsibilities of the parties involved. 1.5.2 Contractor's Responsibilities. The Contractor shall be responsible for WPSs, qualification of welding personnel, the Contractor's inspection, and performing work in conformance with the requirements of this code and contract documents. 1.5.3 Inspector's Responsibilities 1.5.3.1 Contractor Inspection. Contractor inspection shall be supplied by the Contractor and shall be performed as necessary to ensure that materials and workmanship meet the requirements of the contract documents. 1.5.3.2 Verification Inspection. The Engineer shall determine if Verification Inspection shall be performed. Responsibilities for Verification Inspection shall be established between the Engineer and the Verification Inspector.

21. Section 1. General Requirements 1.6 Approvals All references to the need for approval shall be interpreted to mean approval by the Authority Having Jurisdiction or the Engineer.

22. Section 1. General Requirements 1.7 Mandatory and Nonmandatory Provisions Shall . Code provisions that use "shall" are mandatory unless specifically modified in contract documents by the Engineer. Should . The word "should" is used to recommend practices that are considered beneficial, but are not requirements. May . The word "may" in a provision allows the use of optional procedures or practices that can be used as an alternative or supplement to code requirements. Those optional procedures that require the Engineer's approval shall either be specified in the contract documents, or require the Engineer's approval. The Contractor may use any option without the Engineer's approval when the code does not specify that the Engineer's approval shall be required.

23. Section 1. General Requirements 1.8 Welding Symbols Welding symbols shall be those shown in AWS A2.4, Standard Symbols for Welding , Brazing , and Nondestructive Examination. Special conditions shall be fully explained by added notes or details.

24. Welding symbols

25. Welding symbols

26. Welding symbols

27. Welding symbols

28. Welding symbols

29. Welding symbols

30. Welding symbols

31. Welding symbols

32. Welding symbol (general)

33. Section 02, 03 will be discussed later Definition of terminologies and the list of references will be discussed during the course and a complete description will be give in the latter part. Section 02 – Normative References Section 03 – Terms and Definitions.

34. Section 04. Design of welded connections Part A-Common Requirements for Design of Welded Connections (Non tubular and Tubular Members) Part B-Specific Requirements for Design of Non tubular Connections (Statically or Cyclically Loaded). The requirements shall apply in addition to the requirements of Part A. Part C-Specific Requirements for Design of Non tubular Connections (Cyclically Loaded). When applicable, the requirements shall apply in addition to the requirements of Parts A and B.

35. Section 04. Design of welded connections Part A-Common Requirements for Design of Welded Connections (Non tubular and Tubular Members)

36. Section 04. Design of welded connections When the length of end-loaded fillet welds exceeds 100 but not more than 300 times the weld size, the effective length shall be determined by multiplying the actual length by the reduction coefficient When the length exceeds 300 times the leg size, the effective length shall be taken as 180 times the leg size

37. Section 04. Design of welded connections

38. Section 04. Design of welded connections

39. Section 04. Design of welded connections

40. Section 04. Design of welded connections PART B, Specific Requirements for Design of Nontubular Connections (Statically or Cyclically Loaded ) In General The specific requirements of Part B together with the requirements of Part A shall apply to all connections of nontubular members subject to static loading. The requirements of Parts A and B, except as modified by Part C, shall also apply to cyclic loading.

41. Section 04. Design of welded connections

42. Design of a Butt welded joints Butt joints are extensively used in pressure vessels , The strength of butt weld joint is obtained by considering joint efficiency ( η ). Normally, η = 0.75 – 0.90 F F h l Section of joint plan of joint Then F= hxlx η x σ Where, h =plate thickness, σ =permissible tensile stress, l =length of weld, η =joint efficiency.

43. Design of but welded joints Example 01. A gas storage tank consists of a cylindrical Shell of 3 m inner diameter. It consists of hemispherical shells by means of butt welded joint as shown in Figure. The thickness of the cylindrical shell as well as the hemispherical cover is 20 mm. Determine the allowable internal pressure to which the tank may be subjected, if the permissible tensile stress in the weld is 85 N/mm 2 . Assume efficiency of the welded joint as 0.80. Solution. F= hxlx η x σ F=20x x3000 x0.80x 85 = 12,822,857 N P internal x Projected area = Force (F), P internal = internal pressure P internal = 12,822,857/1.5 2 x π P internal =1,813,333 N/m 2  

44. Some other examples API 650 Pressure vessels .

45. Design of a fillet weld joint h = weld size, weld length. h = weld size, weld length. t= weld throat, (h cos ( , 0.707h)   σ = Permissible stress Τ t = shear stress Τ t = shear stress perpendicular to the weld Τ l = shear stress along the weldment (along the axis of the weld) σ = Permissible stress Butt welds (Beveled grove). Fillet welds, (Single fillet).

46. Design of a fillet weld Example 02. AWS rule is Applied stress less than the minimum of 0.3 x and 0.4x Applied force = 50,000N Area = 2x(0.707x6xL)= 8.48L Then, applied force = AWS D1.1 says, Allowable stress shall be minimum of (1.) 0.3 x (2.) 0.4x 0.3 x 410 = 123 Mpa 0.4x 250 = 100 Mpa (consider as per the rule ) Therefore, 50,000 100x8.48L L 58.96 mm selected L would be 60 mm  

47. Section 05 & 06. Wps , pqr and wpq WPS - is a formal written document describing standard welding procedures PQR - is completed the test piece is subjected to Non-destructive and destructive testing as specified in the applicable standard, if all testing is successful a WPS is written from and supported by the PQR WPQ- A Welder Performance Qualification (WPQ) is a test certificate that shows whether a welder possesses the necessary experience and knowledge to perform the specifications of a particular weld procedure.

48. Section 05. pre-qualification of wps 5.1 General This clause contains requirements for prequalified Welding Procedure Specifications (WPSs). These WPSs are exempt from the requirements for testing required It is divided into eight parts as follows: Part A - WPS Development Part B - Base Metal Part C - Weld Joints Part D -Welding Processes Part E - Filler Metals and Shielding Gases Part F - Preheat and Interpass Temperature Requirements Part G-WPS Requirements Part H -Post Weld Heat Treatment

49. Section 05. A. prequalified WPS DEVELOPMENTs

50. Section 05. B. Base metals in WPS development work

51. Part C – Welding joints

52. Part C. Weld joints

53. 7. Fabrication Baking Electrodes. Electrodes exposed to the atmosphere for periods greater than those allowed, shall be baked as follows: ( 1) All electrodes having low-hydrogen coverings conforming to AWS A5.1 shall be baked for at least two hours between 500°F and 800°F [260°C and 430°C], or ( 2) All electrodes having low-hydrogen coverings conforming to A WS A5.5 shall be baked for at least one hour at temperatures between 700°F and 800°F [370°C and 430°C]. All electrodes shall be placed in a suitable oven at a temperature not exceeding one half the final baking temperature for a minimum of one half hour prior to increasing the oven temperature to the final baking temperature. Final baking time shall start after the oven reaches final baking temperature.

54. 7 Fabrications Surfaces to be welded, and surfaces adjacent to the weld, shall be cleaned to remove excessive quantities of the following: ( 1) Water ( 2) Oil ( 3) Grease ( 4) Other hydrocarbon based materials Welding on surfaces containing residual amounts of foreign materials is permitted provided the quality requirements of this code are met.

55. Fabrication Machining, thermal cutting, gouging (including plasma arc cutting and gouging), chipping, or grinding may be used for joint preparation, or the removal of unacceptable work or metal, except that oxygen gouging shall only be permitted for use on as-rolled steels Electric arc cutting and gouging processes (including plasma arc cutting and gouging) and oxyfuel gas cutting processes are recognized under this code for use in preparing, cutting, or trimming materials . In making welds under conditions of severe external shrinkage restraint, once the welding has started, the joint shall not be allowed to cool below the minimum specified preheat until the joint has been completed or sufficient weld has been deposited to ensure freedom from cracking

56. 7. Fabrication Statically Loaded Nontubular Structures. Variations from flatness of webs having a depth, D, and a thickness, t, in panels bounded by stiffeners or flanges, or both, whose least panel dimension is d shall not exceed the following: Intermediate stiffeners on both sides of web where D/t < 150, maximum variation = d/100 where D/t 2'. 150, maximum variation = d/80 Intermediate stiffeners on one side only of web where D/t < 100, maximum variation = d/100 where D/t 2'. 100, maximum variation = d/67 No intermediate stiffeners where D/t 2'. 100, maximum variation = D/150

57. 7. Fabrication Cyclically Loaded Nontubular Structures. Variation from flatness of webs having a depth, D, and a thickness, t, in panels bounded by stiffeners or flanges, or both, whose least panel dimension is d shall not exceed the following: Intermediate stiffeners on both sides of web Interior girders where D/t < 150 maximum variation = d/115 where D/t 2'. 150-maximum variation = d/92 Fascia girders where D/t < 150 maximum variation = d/130 where D/t 2'. 150-maximum variation = d/105 Intermediate stiffeners on one side only of web Interior girders where D/t < 100-maximum variation = d/100 where D/t 2'. 100-maximum variation = d/67

58. 7. Fabrications Measuring bevel angle Measuring leg length Measuring R (reinforcement)

59. 8. Inspection 8.1.3 Definition of Inspector Categories 8.1.3.1 Contractor's Inspector. This inspector is the duly designated person who acts for, and in behalf of, the Contractor on all inspection and quality matters within the scope of the contract documents . 8.1.3.2 Verification Inspector. This inspector is the duly designated person who acts for, and in behalf of, the Owner or Engineer on all inspection and quality matters within the scope of the contract documents . 8.1.3.3 Inspector(s). When the term inspector is used without further qualification as to the specific inspector category described above, it applies equally to inspection and verification within the limits of responsibility described in

60. Qualification of Inspection Personnel 8.1.4.2 Basis for Qualification of Welding Inspectors. Inspectors responsible for acceptance or rejection of material and workmanship on the basis of visual inspection shall be qualified. The acceptable qualification basis shall be one of the following : ( 1) Current or previous certification as an AWS Certified Welding Inspector ( CWl ) or Senior Certified Welding Inspector ( SCWl ) in conformance with the requirements of AWS QCl , Standard for AWS Certification of Welding Inspectors, ( 2) Current or previous certification as a Level 2 or Level 3 Welding Inspector in conformance with the requirements of Canadian Standard Association (CSA) Standard Wl 78.2, Certification of Welding Inspectors, ( 3) Current or previous qualification as a Welding Inspector (WI) or Senior Welding Inspector (SWI) in conformance with the requirements of AWS B5.1, Specification for the Qualification of Welding Inspectors, ( 4) Current or previous qualification as an ASNT SNT-TC- lA - Level II in conformance with the requirements of ASNT Recommended Practice No. SNT-TC JA. Personnel Qualification and Certification in Nondestructive Testing . or ANSI/ASNT CP-189 ASNT Standard for Qualification and Certification of Nondestructive Personnel or An individual who, by training or experience, or both, in metals fabrication, inspection and testing , is competent to perform inspection of the work.

61. 8. Inspection

62. 8. Inspection

63. 8. Inspection

64. 8.0 Inspection

65. 9.0 Stud welding

66. 10. Tubular structures

67. Even in plumbing engineering

68. 11. Strengthening and repair of existing structures

69. BS 5950-1: 2000 Requirement structural engineering view Section 6.7 Welded connection Section 6.8 Design of fillet welds Section 6.9 Design of but welds

70. The End Thanks to IESL and the audience for listening me To all my present and future clients for giving me an opportunity to gather these practical experiences.