Study On Welding Procedure Specifications As Per ASME Sec Ix
IJSRD - International Journal for Scientific Research & Development Vol. 4, Issue 04, 2016 ISSN (online): 2321-0613Study on Welding Procedure Specifications as Per ASME Sec IxSatish.B.G1 Prof. Arunkumar Jeergi21P.G. Student 2Professor1Department of Production Engineering 2Department of Mechanical Engineering1,2PDA college, Gulbarga, KarnatakaAbstract— A welding procedure Specification (WPS) is theformal written document describing welding procedures,which provides direction to the welder or welding operatorsfor making sound and quality production welds as per thecode requirements. The purpose of the document is to guidewelders to the accepted procedures so that repeatable andtrusted welding techniques are used. A WPS is developedfor each material alloy and for each welding type used.Specific codes and/or engineering societies are often thedriving force behind the development of a company's WPS.A WPS is supported by a Procedure Qualification Record(PQR or WPQR). A PQR is a record of a test weldperformed and tested (more rigorously) to ensure that theprocedure will produce a good weld. It is the responsibilityof every individual organization to conduct the weldingprocedures and welder qualifications tests and record andfollow up the code like boiler pressure vessel code ASMEsection IX. The scope of our project is to understand therequirements of the pressure vessel code with regards to themaintenance of quality of welding and how it is ensured. Wewill prepare a welding procedure as per the boiler pressurevessel code, witness the welding for monitoring the weldingvariables like current, voltage, type of electrode, type ofmaterial etc. Witnessing the mechanical tests like TensileTest, Bend Test of the test specimens which are prepared asper the standard.Key words: ASME, WPSProduct Qualification Record is another type ofdocument that also refers to welding. However, unlike WPS,the PQR document’s purpose is to serve as a checklist orrecord of compliance regarding the standard requirements ofan appropriate welding procedure. the PQR form covers allthe welding parameters in the WPS document. In addition, italso includes some observations or other matters regardingwelding procedures and specific tests like tensile tests andguided bend tests. It may also show the visual inspectionand fillet weld test results.Another important component of the PQR is thedisclosure of relevant information, such as the welder’sname and the name of the person who did the inspection,and even the dates with the acknowledgment of themanufacturer or contractor. the PQR is prepared by aqualified or licensed individual and submitted to the peopleconcerned .the inspector will then endorse the company andits product to the industry and market.A PQR is seen as complementary to a WPSbecause there are times when the PQR document is used tomake a WPS document.A. Stages in Welding Procedure and Welder ApprovalI. INTRODUCTION[1]Welding Procedure Specification (WPS). A WPS is awritten qualified welding procedure prepared to providedirection for making production welds to Coderequirements. The WPS or other documents may be used toprovide direction to the welder or welding operator to assurecompliance with the Code requirements. A WPS used forCode production welding shall be available for referenceand review by the Authorized Inspector (AI) at thefabrication site. A WPS is supported by a ProcedureQualification Record (PQR).Procedure Qualification Record (PQR). The PQR isa record of variables recorded during the welding of the testcoupons. It also contains the test results of the testedspecimens. Recorded variables normally fall within a smallrange of the actual variables that will be used in productionwelding.[2] WPS is a set of welding instructions. It aids inplanning and ensuring quality control of the welded productas well as future reproductions of the product. Weldingparameters, such as joint design, position, base metals,electrical characteristics, filler metals, technique, shielding,preheat, and post-weld heat treatment are all detailed in theWPS document.WPS further explains the rules and detailsof the test and how the pieces should be assembled. Simplyput, a WPS is like a blueprint for welders to produce thesame quality of welded product over and over again.Fig. 1: Stages in welding procedure and welder approvalAll rights reserved by www.ijsrd.com1354
Study on Welding Procedure Specifications as Per ASME Sec Ix(IJSRD/Vol. 4/Issue 04/2016/325)B. American Society of Mechanical Engineers [ASME]In 1911, The American Society of Mechanical Engineersestablished the Boiler and Pressure Vessel Committee toformulate standard rules for the construction of steamboilers and other pressure vessels. In 2009, the Boiler andPressure Vessel Committee was superseded by the followingcommittees:a) Committee on Power Boilers (I)b) Committee on Materials (II)c) Committee on Construction of Nuclear FacilityComponents (III)d) Committee on Heating Boilers (IV)e) Committee on Nondestructive Examination (V)f) Committee on Pressure Vessels (VIII)g) Committee on Welding, Brazing, and Fusing (IX)h) Committee on Fiber-Reinforced Plastic PressureVessels (X)i) Committee on Nuclear Inservice Inspection (XI)j) Committee on Transport Tanks (XII)k) Technical Oversight Management Committee(TOMC)Section IX of the ASME Boiler and PressureVessel Code relates to the qualification of welders, weldingoperators, brazers, and brazing operators, and the proceduresthat they employ in welding and brazing. It is divided intotwo parts: Part QW gives requirements for welding and PartQB contains requirements for brazing.ASME Section IX is a document referenced for thequalification of material joining processes by variousconstruction codes such as Section I, III, IV, VIII, XII, etc.These particular construction codes apply to specific typesof fabrication and may impose additional requirements orexemptions to Section IX qualifications. Qualification inaccordance with Section IX is not a guarantee thatprocedures and performance qualifications will beacceptable to a particular construction code.C. Process Parameters Involved in WPS1) Welding processWelding is a process of joining two similar or dissimilarmaterials by the application of heat and filler metal with orwithout application of pressure. On cooling, the moltenedges fuse together to form a strong joint. A filler metal isadded to the molten parent metal. The most popularprocesses are shielded metal arc welding (SMAW), gasmetal arc welding (GMAW) and gas tungsten arc welding(GTAW). All of these methods employ an electric powersupply to create an arc which melts the base metal(s) to forma molten pool. The filler wire is then either addedautomatically (GMAW) or manually (SMAW & GTAW)and the molten pool is allowed to cool. Shielded metal arcwelding (SMAW) is an arc welding process in whichcoalescence of metals is produced by heat from an electricarc that is maintained between the tip of a covered electrodeand surface of the base metal in the joint being welded.In this welding procedure specification (WPS) theshielded metal arc welding(SMAW) process is used as perboiler vessel pressure code ASME Sec Ix.Fig. 1: Principle of operationIn this process the heat required for welding isgenerated by the electric arc formed between metallicelectrode and base metal. When the welder touches the plateto be welded with the electrode, it directly short circuits thepower supply and immediately a heavy current flows whichmelts the tip of the electrode like blowing of the fuse, thusinitiating the welding arc. if the welder maintains the arcgap, the arc continous to remain stable and the arc heatmelts the plate, electrode and the flux coating.2) Base MetalThe base metal used is mild steel and its specification typeand grade as per ASME Sec IX is IS2062 Grade B.[3] The IS2062 Gr B mild steel is general structural steel forfabrication. The chemical composition of IS2062 Gr B isMnSiC%S%P%C.E %Grade%%MaxMaxMaxMaxMaxMaxB0.221.50.045 0.045 0.04 0.041Table 1: chemical composition of IS2062 Gr BMechanical properties IS2062 E250 Grade BGrade UTS (MPa) Min Y.S (MPa) Min E I % MinB41025023Table 2: mechanical properties of base metal IS2062 MildsteelUTS- Ultimate tensile stress, YS- Yield strength, EI- Elongation in percentage3) Filler MetalElectrode and filler wires are used as filler metals which fillsor joints the base metals in any welding process. Fordifferent base metals different types of filler metals andelectrodes should be used. They should be as recommendedby the welding engineering department. They are availablein different sizes for different weld edges.The filler metalused for shielded metal arc welding process is E7018.4) Welding PositionThe weld position is considered to be an important factor. Inthis WPS (welding procedure specification) the weldprogression is uphill and welding position is 3G.5) PreheatPreheat is always specified as the minimum temperature towhich the parent material must be heated before weldingand maintained during welding. The purpose of preheat is tominimize the risk of cracking in the weld metal and heataffected zone. uniform preheating reduces the distortion towelding.6) Post Weld Heat TreatmentPost weld heat treatment (PWHT) defined as any heattreatment after welding, is often used to improve theAll rights reserved by www.ijsrd.com1355
Study on Welding Procedure Specifications as Per ASME Sec Ix(IJSRD/Vol. 4/Issue 04/2016/325)properties of a weldment. In concept, PWHT can encompassmany different potential treatments; however, in steelfabrication, the two most common procedures used are Postheating and Stress relieving.PWHT is required to increase the resistance tobrittle fracture and relaxing residual stresses. Other desiredresults from PWHT may include hardness reduction, andmaterial strength enhancements. As per boiler vesselpressure code the PWHT is carried for plates thicknessabove 40mm.II. EXPERIMENTAL PLAN AND DETAILSA. Experimental Setup and Work MaterialsThe experiments were conducted at shivpra cranes,Hyderabad on mild steel IS2062 Gr. B Plate of thickness16mm were cut into 20x150x300 and welded with samedimension plate.Fig. 3: shows preparatiom test coupons from welded plate.Fig. 2: welded specimenB. Preparation of Test CouponThe welded specimen is cut and machined into number oftest coupons. the purpose of making test coupons is toconduct tensile test and bend test for qualifying the codes asper ASME Sec ix.[4] The test coupons are prepared as per boilervessel pressure code i.e ASME Sec ix. The number of testcoupon prepared for tensile test is two, and four test couponsare prepared for bend test. The test coupon is shown infigure below.Tensile test couponsBend test couponFig. 4: shows Two tensile test coupons and four bend testcoupons after machining welded plate[6] The tensile test coupon has been machined withdimensions shown in figure below.Length sufficient to extend into grip equal to two Thirdsgrip lengthFig. 5: Reduced tensile test couponC. Electrical CharacteristicsWeld FillerpassSmawE7018CappingAll rights reserved by www.ijsrd.comSmawE70181356
Study on Welding Procedure Specifications as Per ASME Sec Ix(IJSRD/Vol. 4/Issue 04/2016/325)metalDiaCurrent type & 120140-180180Volts(range)22-2624-2824-28Table 3: electrical charactersticsThe electrical characterstics defines the theoretical wpsvalues prepared by the organization head. This electricalcharacterstics will followed by weld operator duringwelding. Its is also inspected by weld inspector duringwelding.D. Testing Of Weld Specimen[5] The design of nearly every component and structure isbased on minimum tensile properties. As welded jointscontain metallurgical and often compositional differencesthat result from the welding process, the effects of thesechanges on the mechanical properties of the weldment mustbe assessed. Some strength tests, such as tension tests,measure tensile strength directly,while others, such as thepeel test, verify that the weld is as strong as the base metal.The techniques used to evaluate the strength of weldmentsare discussed below.1) Mechanical TestingMechanical testing of weld joints may be carried forfollowing reasons1) Welding procedure approval2) Welder approval3) Production quality approvalIn mechanical testing representative test samples areproduced under similar conditions to the in servicecomponents are normally used and comparison is made.thepurpose of mechanical testing is to asses the properties ofweld joints.The most frequently used mechanical tests are1) Tensile test2) Bend test3) Hardness4) Impact1) Tensile test: in tensile test stress is applied on oppositedirection to pull the two ends apart. The tensile test usedasses the following:1) Yield point of the specimen2) Ultimate tensile strength3) Ductility of the specimen, expressed as %elongation.2) Bend test: the bend test is usually carried out todetermine the soundness of the weld zone.thecommonly applied bend test is transverse bend test,there are three ways to perform this type of bend test.1) Face bend test2) Root bend test3) Side bend test[6] Transverse bend tests may be either face, root, orside tests, depending upon the area that is in tension duringtest.Face bend tests are performed with weld face in tension.Root bend tests are performed with weld root in tension, andside bend can be bent toward either side. Side bendstypically can be used when bend testing plates are thickerthan 10mm to 19mm.side bend tests strain entire crosssection of the weld. Thus they are especially useful forexposing the discontinuities that may not contribute tofailure in face or root bend tests because of their locationnear the midthickness. The figure below shows the threetypes of bend test.Fig. 6: shows three types of bend test.E. Format for WPSThe written document of Welding Procedure Specificationwill be in order mentioned as below which will be followedby the Welder.QW-482 WELDING PROCEDURE SPECIFICATIONS(As per ASME Sec IX)Joint (QW-402)Joint DesignAllRoot Spacing2mm – 3mmBackingYesBacking Material Weld MetalTable 4: Joint DesignFig 7: Shows joint design of weld test coupon.Base Metals (QW-403)P.GroupP.Group11 type andTotype andGr BGr BgradegradeAll rights reserved by www.ijsrd.com1357
Study on Welding Procedure Specifications as Per ASME Sec Ix(IJSRD/Vol. 4/Issue 04/2016/325)The type of bend test conducted was side bend test, the sidebend test is said to be passed when there is nodiscontinuities such as cracks, voids etc is not found in theweld zone. Hence all four side bend test are passed there isno defects or discontinuities are found as shown in figurebelow.Thickness llFilletAllRangeMin. Pass thickness 1/2in.YES(13mm). [Yes/No]Filler Metals (QW-404)ProcessSMAWSpec. No [SFA]5.1AWS No. [Class]E 7018F. No4A. No1Size of filler metals3.15, 4mmSupplemental filler metalsNAGroove: 5mm-32mmWeld metal thicknessrangeFillet: All SizesTrade name [Flux]NAElectrode Flux [Class]NAType of FluxNAConsumable InertNATable 5:III. RESULTS AND DISCUSSIONSIn this paper the importance of wps is studied and applied toshielded metal arc welding with reference to ASME Sec IXboiler pressure vessel code. The welding procedure will beapproved by inspection services. The mechanical tests liketensile test, guided bend test are part of wps which areobtained better results with IS2062 E250 Grade B as basemetal which is used as structural steel for fabrication.Mechanical Test silecoupon T1Tensilecoupon T2IS:2062-2011E250 GR BIS:2062-2011E250 GR Table 6:Sl NoL0 (mm)A0 (mm2)Yield Load (KN)Ultimate Load (KN)Lf (mm)Yield Strength (N/mm2)UTS (N/mm2)Elongation 8141.6465.03326.11474.4330.06Table 7:Lo gauge length, Ao initial area of test couponLf final gauge length, Ao final areaThe tensile test results is said to be passed when thetest specimen achieves minimum Ultimate tensile stress,yield stress and elongation. The minimum ultimate tensilestress, yield strength, and elongation as per boiler ongation). The obtained results of tensile testcoupons are 472.19MPa(UTS), 474.43MPa(UTS), andcorresponding elongation results are 32.7%, 30.06%.Weld zoneFig. 7: Side bend coupon 1IV. CONCLUSIONSIn this paper a recent study on welding procedurespecifications has been made which represents the followingfacts:1) The boiler pressure vessel code i.e ASME Sec IX isfollowed and prepared a WPS with shielded metal arcwelding process and achieved better results. From thiswps the welder is going to follow up certain weldparameters during SMAW in order to minimize reworkat fabrication sites.2) From this WPS the welder performance can beestablished in the fabrication industry i.e welderperformance qualifications, in which the welderperformance is supposed to be enhanced by consideringmechanical tests conducted on welded test coupon madeby welder with certain welding position, electrode, basemetal etc.3) Preparation of wps improves welding procedure,performance of individual when there is a repitativework comes at fabrication site such that the welder isselected based on performance.4) By following wps the fabrication industry will benefitbetter production quality without wastage and rework ofmaterial.5) From the wps the better quality welders with differentwelding process and different welding positions will beobtained in the fabrication industry.All rights reserved by www.ijsrd.com1358
Study on Welding Procedure Specifications as Per ASME Sec Ix(IJSRD/Vol. 4/Issue 04/2016/325)REFERENCES[1] American Society of mechanical engineers section IXboiler pressure vessel code committee onwelding,brazing,and fusing. W.J. Sperko, M. Bernasek,J.G. Feldstein, P.D.Flenner, J.S. Lee, R.M. Jessee,M.J.Rice, T.Melfi, D.K. Peetz.[2] American society of mechanical engineers boilerpressure vessel code section IX sub committee ongeneral requirements, P.L. Sturgill, E.W. Beckman ,J.P.Bell, G. Chandler, P.R. Evans, A. Howard,R.M.Jessee.[3] American society of mechanical engineers, boilerpressure vessel code section IX, sub committee onmaterials, M.Bernasek,T.Anderson, J.L.Arnold,E.Cutlip, L. Harbison, P.L Sturgill, S.S.Fiore.[4] American society of mechanical engineers, boilerpressure vessel section ix, sub committee on procedurequalification, D.A.Bowers, M.J.Rice, W.J.Sperko,T.C.Wiesner, S.A Spargue, M.B.Sims.[5] American Welding Society (AWS) Committee onMechanicalTesting of Welds, 1998, StandardMethods for Mechanical Testing of Welds, ANSI/AWS[6] American Society for Testing and MaterialsSubcommittee E28.02. 1997. Standard test method forguided bend test for ductility of welds. ASTM E 190-92(1997).All rights reserved by www.ijsrd.com1359
manufacturer or contractor. the PQR is prepared by a qualified or licensed individual and submitted to the people concerned .the inspector will then endorse the company and its product to the industry and market. A PQR is seen as complementary to a WPS because there are times when the PQR
6.3 Mechanised/automatic welding 114 6.4 TIG spot and plug welding 115 7 MIG welding 116 7.1 Introduction 116 7.2 Process principles 116 7.3 Welding consumables 130 7.4 Welding procedures and techniques 135 7.5 Mechanised and robotic welding 141 7.6 Mechanised electro-gas welding 143 7.7 MIG spot welding 144 8 Other welding processes 147 8.1 .
test sample following the welding procedure specifications showed high strength and ductility compared with the samples without welding procedure specifications. This phenomenon occurs due to the grain size of the martensitic structure and a little bit of growth compared with a sample without following the welding procedure specifications.
3. Classification of Underwater Welding Underwater welding may be divided into two main types: a) Wet welding b) Dry welding Fig. 3.1 Classification of underwater welding 3.1 Wet welding 3.1.1. Wet welding with coated electrode Wet welding is performed at ambient pressure with the welder-diver in the water and no physical barrier
2. DISSIMILAR METALS WELDING This section briefly presents the different consider-ations of welding procedure specifications for fusion welding of dissimilar metals, focusing on the GMAW Table 1. Welding procedure requirement for ferrous metal [10,11]. Considerations Fundamentals Service consideration Filler metal selection Welding process .
seam butt welding resistance butt welding flash butt welding resistance butt welding shielded unshielded other process plasma laser resistance butt welding inert gas welding submerged arc welding atomic hydrogen shielded metal arc welding (coated electrode) esepl w w w . e u r e k a e l e c t r o d e s .
the welding processes most often used in today's industry including plasma arc cutting, oxyfuel gas cutting and welding, Gas Metal Arc Welding (GMAW), Flux-Cored Arc Welding (FCAW), Shielded Metal Arc Welding (SMAW), and Gas Tungsten Arc Welding (GTAW). Flat welding positions and basic joints will be practiced. Pipe and tube welding
the limited depth of underwater welding. Welding equipment transformed from manual welding to underwater automatic welding. The efficient and low-cost underwater welding was achieved[7]. In order to study the automatic welding technology under larger deep-water environment, the underwater automatic welding system was designed in this paper. The
10.6 Braze-welding 460 Exercises 466 11 Joining processes (welding) 467 11.1 Fusion welding 468 11.2 Oxy-acetylene welding 468 11.3 Manual metal-arc welding 490 11.4 Workshop testing of welds 504 11.5 Miscellaneous fusion welding processes 506 11.6 Workholding devices for fusion welding 509 11.7 Resistance welding 515
