The welding consumable should be selected to correctly match or overmatch the strength of the pipe. When repair welding is done on machinery many parts that are not removed should be protected from weld spatter, flame cutting sparks, and other foreign material. Rules for classification and construction ii materials and. Here, the alternative routes for welding procedure approval are described together with the requirements for welder or welding operator approval. The welding procedure approval record wpar is a record of this weld. For a given application, the main way of ensuring adequate weld quality is to specify the procedure and the skill level of the welding operator. Remove any burrs or spot weld nuggets from the mating flanges, and repair any damage. If you have a 20,000 lb body, 2% of the castings is 400lb of weld. When using temperature measuring crayons, any residual crayon shall be removed before welding over the marked area.
Weld setting exact weld settings cannot be given because no two jobs are the same. All welding shall be done using new york state field welders certified to weld fillets in the overhead 4f position. Welding procedure specification for shielded metal arc welding of steel pipe and fittings. Today, esab can offer repair and maintenance consumables for most materials and welding processes. Before beginning to weld the pipe, the procedure should be checked to assure that the correct electrode is being used. Castings i am familiar with average about 12% replacement of their volume with weld metal repair. The qualifications of welding procedures and welders obligatorily be done. Weld repair of manganese frogs for enhanced safety in. We generally have a wps that specifically covers the repair operation as that is slightly different from the original weld procedure including backgouging rather air arc, grinding, machining, torch, etc to get rid of the discontinuities that. Repair welding can be carried out as a logical procedure that ensures the production of a usable and safe component, or it can be approached haphazardly. Interpass temperature shall be measured on the weld metal or on the base metal near the weld metal prior to beginning the subsequent weld bead pass.
This procedure covers the requirements for repairing all nonconformities in base metal surfaces, the repair of nonconformities in edge preparation and the. I agree that castings can be far from perfect material, thus the need for welding when higher integrity is requried than the casting provides without the repair. The following evaluation of the basic characteristics of the repaired site point to the suitability of the selected technological parameters of the repair procedure. The repair welding location or area must be surveyed and all safety considerations satisfied. The latter approach results in poorquality workmanship and can lead to failed parts, large warranty claims and dissatisfied customers 1. We generally have a wps that specifically covers the repair operation as that is slightly different from the original weld procedure including backgouging rather air arc, grinding, machining, torch, etc to get rid of the discontinuities that made the. A crack in a weld is discovered in a bevel groove, but the engineer determines it can be repaired. Procedures for repair welding and surfacing total materia article. Welding fundamentals preheat, interpass temperatures, and postheat preheating involves heating the base metal immediately surrounding the weld to a speci. Scribd is the worlds largest social reading and publishing site. Since carbon is a major factor that affects hardness of lowalloy steels, both cleaning and degreasing are important during all stages of the process.
Weld repairs are carried out by melting and depositing a filler metal on the material to repair. Corrosionresistant weld overlays are used to improve the service life of components made with an otherwise corrosionprone material. Gl, which was then filled with a weld metal using mag 5 technology. If the wpar is approved by the examiner, it is used to finalise one or more wpss which is the basis for the work instructions given to the welder. Fillet weld certification welding procedure wps 8 81 thru 83 3g4g plate certification welding procedure wps 9 91 thru 93 6g pipe certification welding procedure wps 10 101 thru 103. Procedures for repairing structural cracks use the following instructions to repair structural cracks. A special welding procedure ensures that the optimal strength and ductility is maintained. The equipment is relatively simple, inexpensive, and portable. The qualifications of welding procedures and welders obligatorily be done according to the welding procedure specification. Pressure welding of noble metals over 2,000 years ago forge welding blacksmiths over 1,000 years ago modern welding 1880s. Just last week a customer contacted us asking for help in developing a repair welding procedure for a damaged cracked truck frame. One of the major concerns in arc welding based overlays is dilution. The key document is the welding procedure specification.
Since then, this repair technique has been further developed and implemented in other segments. Girders were fatigue tested until cracks grew to a predetermined length. Sample welding procedure specifications are available on our website. Asme weld repair asme mechanical code issues engtips. If a part requires rework, a thorough welding procedure should be established to minimize the effect of the repair. Paint shall be removed at least 6 inches from areas of work prior to flame cutting.
The welding process generally involves melting and subsequent cooling, and the result of this thermal cycle is distortion if the welded item is free to move, or residual stress if the item is. Straighten the mating panel edges, if necessary to ensure a proper fitup with the replacement core support. Replace the removed fillet weld using welding procedure specification wps fillet weld stiffenertop flange. Fillet weld a weld of approximately triangular cross section that joins two surfaces approximately at right angles to each other in a lap joint, tjoint, or corner joint. Review of weld repair procedures for low alloy steels designed to. Weld repairs to aged and degenerated materials are prone to early failure on return to service unless strict preparation and controlled welding procedures are. Weld procedure qualification weld procedure qualification understand the intended application for which the wps will be used things to know prior to qualifying a welding procedure know the application for the welding procedure what welding processes are going to. S ome repairs, whether it is repairing a failed weldment or repairing a crack in a casting, may easily be done by simply grinding out the crack and applying more weld. Interpass cleaning chip, file, brush and or grind weld type fillet weld joint details joint design used sketch.
The repair of foundry defects in steel castings using. All welding shall be done using new york state field welders certified to. Welding procedure specification wps may be generated by an authorized person i. Repair and maintenance welding handbook serpantinas. Depending upon exactly how the pqr was run, tested, and written it should really cover you. The welding techniques and associated equipment come in precautionary phase. Its a recipe for a the creation of an acceptable weld it specifies the ingredients and instructions how they are combined the essential variables for a welding procedures should be those factors that can affect the metallurgical result of the welding process. Procedures for repair welding and surfacing total materia. Procedure for stud welding shear connectors, headed anchors and deformed bar anchors 14 350 to 450 amps 34 1450 to 1750 38 525 to 700 amps 78 1700 to 1950 amps 12 750 to 925 amps 1 2000 to 2200 amps 58 1100 to 1400 amps 5. Develop a repair welding procedure now that you have all the details regarding the failure mechanism, understand the service requirements and know which code or standard to follow, you can craft your welding procedure.
The purpose of the welding handbook for maritime welders is to provide guidance in modern welding and related processes and to provide the welder with a source of practical information on the right solution to specific onboard welding problems. The crack in weld joint or a defect in the base metal can be repaired by preparing a u or a v groove to the full depth and length of crack and then fill up by weld metal deposit as described here. Standard practice for steel castings, welding, quali. The repair procedure shall be qualified as per the recognized code such as. Metals engineering unit for a recommended repair procedure. Paper presented at stainless steel world america 2010, houston, texas, usa, 57 october 2010. Perform upperbody measurements and adjacent panel alignment and straightening. This includes the diameter and the classification of the electrode.
Filler diameter mm in current amps alternate filler diameters mm in current amps 5 mm 316 1 or 2 1 1 3. Welding can fill in missing material with 100% bonding, thereby restoring components to 100% of the original dimensions and properties. The filler metal, and the means of protecting it and the weld metal from harmful oxidation during welding, are provided by the covered electrode. The customer expected us to send them a welding procedure specification wps calling out the type of wire, welding variables such as wire feed speed and volts, and any preheat or post weld heat treatment necessary. Your welding procedure shall include joint details including joint preparation, welding process, filler metal, preheat and.
In most cases, all sections will not apply at one facility. Sections applicable to all types of welding and should be completed in all cases are. Mar 28, 2016 a procedure would need to be writtenand possibly qualifiedto complete this repair using another process. A procedure would need to be writtenand possibly qualifiedto complete this repair using another process. Employee responsibilities following instructions that differ from the union pacific railroad standards, fra guidelines and rules outlined inthe track welding rulescould be potentially harmful to the safe operation of the railroad and must be brought to the attention of the. Nav22 xxii weldingweld repair audit checklist the applicable. All crack repairs should be carried out by a certi. Cra weld overlay dilution and corrosion resistance twi.
Weld repair flue gas recirculation fan duplex stainless steel, 2205 en 1. Do not damage the parts attached to the rear body panel, such as the rear floor pan, which are not to be replaced. Examination for acceptance of weld repair per nb4450, if repair excavation is greater than 38 or 10% of component thickness, radiographic examination rt is required existing flaw will be present in repair applications alternative ut exam will. If you are repairing a cracked a36 steel automotive rack you may be okay regardless of what your welding procedure looks like.
In addition, all weld stubs, weld spatter, weld slag, and other residue should be removed from the repair area to make it cleaner than it was originally. Grinding dust is particularly troublesome and every effort should be made to remove it entirely since it is abrasive and can get into working joints, bearings, etc. Weld procedure qualification weld procedure qualification understand the intended application for which the wps will be used things to know prior to qualifying a welding procedure know the application for the welding procedure what welding processes are going to be used during construction. A weld procedure qualifications check applicable boxes. Weld repair of manganese frogs for enhanced safety in shared. The repair procedure should take care of the requirements of the base metal, welding consumables, sequential weld deposits, requirements of preheat, interpass temperature, post weld heating, pwht, impact test and the ndt requirements. The latter approach results in poorquality workmanship and can lead to failed parts, large. Xxii welding weld repair audit checklist this process guideline is divided into eight 8 sections.
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