通用汽车工程标准 GM9621P 焊接工艺控制流程

Welding Process Control Procedure1 Scope1.1 Purpose. This standard defines weld in-spection and welding equipment process control requirements for producers of GM welded or mechanical clinched product.1.2 Application. The requirements of this stan-dard are applicable to welding and joining proc-esses utilized by a General Motors fabricating and/or assembly plant to join automotive parts and assemblies.2 ReferencesNote: Only the latest approved standards are applicable unless otherwise specified.2.1 External Standards/Specifications.ANSI-Z49.1 ISO10447 2.2 GM Standards/Specifications.GMN100722.3 Additional References.WS-4, GM Weld Verification Procedures.3 Procedure3.1 Designation of Responsibility3.1.1 Product Engineering. The product engi-neering function is responsible for defining the structural requirements of the vehicle. These requirements include the joining method, quan-tity, location,and product tolerances.Product acceptance criteria is to be consistent with pub-lished GM Engineering Standards.3.1.2 Manufacturing Engineering. The manu-facturing engineering function is responsible for evaluating the product design for manufactura-bility. Manufacturing engineering defines the process, type of tooling, and operational se-quences to manufacture the product in confor-mity to the released design. 3.1.3 Plant Responsibility. The plants must adhere to the product specifications approved by product engineering and the process re-quirements defined by manufacturing engineer-ing. Product engineering must approve any variance from product specifications. Variance from process requirements must be in agree-ment with written procedures.3.2 Process Evaluation.3.2.1 Weld Tool Verification and Qualifica-tion. The procuring manufacturing engineering function must verify that new as built tooling agrees with the tool design and/or Tool and Equipment Statement of Requirements. The applicable section of WS-4, GM Weld Verifica-tion Procedures is to be utilized to perform the verification and qualification activities. Any weld tooling revisions necessitated by this procedure must be completed and tool design documents updated. Records of the verification and qualifi-cation activity are to be maintained.3.2.2 Weld Tool Re-Qualification. Each weld tool must be re-qualified whenever a change occurs in the product or process that was part of the original verification and qualification activity. It is recommended that the re-qualification activ-ity utilize the same process described in WS-4. Records of the re-qualification activity are to be maintained.3.2.3 Equipment Process Monitoring. Equip-ment process monitoring consists of measuring the process parameters established during tool qualification as well as visual evaluation of the equipment functional operation. Equipment process monitoring requirements for various welding and joining processes are contained in the appendices of this standard.3.2.4 Equipment Maintenance. Each location shall have documented plans for the mainte-nance of equipment. The equipment mainte-nance schedule should be consistent with the tool or equipment manufacturers recommenda-tions.3.3 Product Monitoring and Inspection. Prod-uct monitoring and inspection consist of evaluat-ing the welded product with the released design© Copyright 2003 General Motors Corporation All Rights ReservedAugust 2003 Originating Department: North American Engineering Standards Page 1 of 7GM9621PGM ENGINEERING STANDARDSand the applicable GM Engineering Standards to identify, contain, and repair nonconforming weld patterns. Methodologies for physical test-ing of resistance welds are contained in ISO 10447, Welding – Peel and chisel testing of resistance spot, projection or seam welds . The product monitoring and inspection plan for all welds must be described in written procedures or standardized work.Note: Peel testing is the preferred method of inspection for aluminum spot welds. Chisel test-ing is not an acceptable method of inspection for aluminum spot welds.3.3.1 In-Process Inspection and Test (Resis-tance Spot Welds). A deformation or ultrasonic nondestructive check of all spot welds (for all styles and all cells) is recommended to occur 4 times per shift at evenly spaced intervals.The minimum frequency is one check per weld gun and metal stack-up, sampled four times per shift.© Copyright 2003 General Motors Corporation All Rights ReservedConcurrent with the deformation checks, visually inspect for sealer presence if specified and visu-ally inspect all welds for conformance to the applicable product drawing and GM Engineering Standard.3.3.2 In-Process Inspection and Other Tests. Welds and joining techniques other than those mentioned in 3.3.1 should be verified for con-formance to the visual acceptance criteria of the applicable standard a minimum of 4 times per shift.3.3.2 Weld Destruct Test – Assembly Plants. At the Start of System Fill the frequency of full body destruct is one of each new body style per month until process capability is demonstrated and documented. Process capability consists of completing three consecutive destruct tests that meet requirements. The frequency can then be reduced to a quarterly destruct test of each body style.3.3.4 Weld Destruct Test – Fabricating Plants. At Start of Production the frequency of destruct tests is to be one of each assembly per month until process capability is demonstrated and documented. Process capability consists of completing three consecutive destruct tests that meet requirements. The frequency can then be reduced to a quarterly destruct test of each as-sembly.3.4 Weld Image Analysis. Inspection, measur-ing and test equipment to perform the image analysis of weld cross sections must be capable of evaluating the specified measurable criteria toan accuracy of 0.01 millimeters. The use of the Native American Technologies Weld Measuring System (NAMeS)™ is recommended. Weld cross sections are to be viewed at 15X or less magnification.3.4.1 Weld Cross Section. The number of re-quired weld cross section samples is to be de-termined by the specified length of the weld bead in accord with the following table. Table 1: Weld Beads vs Cross SectionsSpecified Weld Bead Length(mm) Number of Cross SectionsLocation of CrossSections 30 or less 1 Midpoint of weld 31 – 1002Equally spaced from each other and from the ends of the welds 100+ 3Equally spaced from each other and from the ends of the welds4 Nondestructive Evaluation (NDE)4.1 Ultrasonic evaluation of resistance spot welds can be utilized in place of the required deformation or destruct tests provided the per-sonnel and process have been qualified in ac-cord with GMN10072, Personnel and ProcessQualification for Ultrasonic Testing of Resistance Spot Welds.5 SafetyWelding, cutting and allied processes can be performed safely with minimal health risk, pro-vided proper procedures are followed and nec-essary precautions are taken. An informative reference that provides guidance for personnel in the safe set-up and use of welding and cutting equipment is the ANSI Z49.1, Safety in Welding, Cutting, and Allied Processes document.6 Release and Revisions6.1 Release. This procedure originated in May1990 and approved by the Weld Committee in May 1990. It was first published in September 1990.6.2 Revisions.Rev Date Description (Organization)A NOV 1990EditorialB MAY 2003Total rewrite to addresswelding and joining (GMNA Weld Council)Page 2 of 7 August 2003GM ENGINEERING STANDARDS GM9621PAppendix AResistance Welding ProcessesTable A1: Spot Weld EquipmentEquipment Monitoring Activity Every CapChange EachShiftWeekly MonthlyVerify electrodes are the ones specified. XVerify electrode alignment. XVerify water cooling. XCheck for any water and/or air leaks. XVerify tip dresser operation. XCheck cables/shunts for wear, cuts and/or loose con-nections.XVerify that the weld schedules, fault settings and step-per settings agree with the Weld Tool Data Sheetsdocumented values.XVerify gun force is within specified limits. X Verify secondary current capability. X Verify gun action including lubrication and flash shields. X© Copyright 2003 General Motors Corporation All Rights ReservedPage 3 of 7 August 2003GM9621P GM ENGINEERING STANDARDSTable A2: Projection Welding EquipmentEquipment Monitoring Activity Every CapChange EachShiftWeekly MonthlyVerify electrodes are the ones specified.XCheck electrodes for excessive wear, proper alignment,and parallelism.XVerify water cooling.XCheck for any water and/or air leaks.XCheck cables/shunts for wear, cuts and/or loose connec-tions.XCheck feeder mechanism for debris and proper operation(if applicable).XVerify error proofing device operation (if applicable). XVerify that the weld schedules and fault settings agree withthe Weld Tool Data Sheets documented values.XVerify gun force is within specified limits. X Verify secondary current capability. X Verify gun action including lubrication and flash shields. X© Copyright 2003 General Motors Corporation All Rights ReservedPage 4 of 7 August 2003GM ENGINEERING STANDARDS GM9621PTable A3: Gas Metal Arc Welding EquipmentEquipment Monitoring Activity During Con-tact TipChange EachShiftWeekly MonthlyVerify shielding gas flow. XVerify wire feed system operation. XVerify torch and mounting bracket are tight and in posi-tion.XCheck torch, nozzle and contact tip for damage. XVerify operation of anti-spatter system. XVerify torch cleaning system operation. XCheck for alternate shorting paths. XCheck gas diffuser for dirt or damage. XVerify tip to work distance and torch position. XCheck conduits and control cables for damage. XCheck gas and anti-spatter hoses for cuts, holes andleaks.XCheck weld wire delivery system and feed drive rolltensioner setting.XCheck electrical return circuit (coppers and cables) fordamage and for completeness.XVerify weld voltage, fault settings, weld current and gasflow rates are within limits posted on the Weld ToolData Sheet.XCheck water cooling to torch (if applicable). X© Copyright 2003 General Motors Corporation All Rights ReservedAugust 2003 Page 5 of 7GM9621P GM ENGINEERING STANDARDSTable A4: Drawn Arc Welding EquipmentEquipment Monitoring Activity EachShift Daily DuringColletChangeMonthlyCheck collet for broken or burned away tines, and checkthat collet nut is tight.XCheck the position or stick out of the probe/flash shield. XCheck piston for stick out. XVerify drop time (at the welder control) does not exceedsetup value by more than 5 milliseconds.XCheck feeders and feed tubes for debris, excessive wear,and correct operation.XCheck work lead circuit (welder control/feeder to workpiece). Ensure cables are intact, connections are tight,and contact blocks function properly.XCheck mount and slide unit for excessive play make suretubes and cables do not inhibit movement.XCheck stick-out from collet, check lift distance and opera-tion.XVerify that arc voltage, current and time are within theprocess tolerances specified on the Weld Tool DataSheet.XCheck feed tubes for wear and proper alignment. XCheck for abrasion between the inner and outer collet XCheck the power feed cable for wear and exposed cop-per.XCheck weld head/gun front end for tight rings, flanges,and nuts.X© Copyright 2003 General Motors Corporation All Rights ReservedPage 6 of 7 August 2003GM ENGINEERING STANDARDS GM9621PTable A5: Mechanical Clinch EquipmentMonthly Equipment Monitoring Activity WeeklyCheck punch for damage and punch tip for excessive wear. XCheck stripper springs for wear, compressed, or broken. XCheck condition of die, look for damage, excessive wear of die blades. XCheck for excessive wear on the anvil. XCheck general condition of clinch unit seals, hoses, and fittings. XVerify operating air or hydraulic pressure is within limits documented on the ToolXInformation Sheet.Check proper punch and die alignment. XCheck correct punch is installed. XCheck for wear of punch holder, is punch loose in holder. XCheck condition of stripper assembly. XCheck that correct die is installed. XCheck condition of slides for excessive wear or loose. XCheck condition of stop blocks, loose or worn. XVerify travel of clinch unit for proper shut height. XVerify operation of proximity switches on dumps and slides. X© Copyright 2003 General Motors Corporation All Rights ReservedAugust 2003 Page 7 of 7。