GM6435M(螺栓焊接标准)

Resistance Projection Welded Automotive Steel Nuts, Studs, cages and Other

Parts

February 2002

Originating Department: North American Engineering Standards, Records and Documentation

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1 Scope

This specification applies to Resistance Projection Welded Steel Nuts, Studs, Cages, and Other Parts.

[Note: The weld acceptance criteria for drawn arc welded steel nuts and studs are no longer addressed in GM6435M. The Drawn Arc acceptance criteria are now contained in GMN7027.]Instructions: The Scope of the specification should amplify the title, state the function of the specification and note any materials or products excluded.

1.1 Purpose. This specification provides acceptance criteria for steel nuts, studs, cages and other parts with solid projections that are resistance projection welded in automotive product that GM is responsible for establishing or approving the product design.

1.2 Application. The criteria established in this specification become mandatory when referenced on a weld drawing. Deviation from any weld criteria provided in this specification must be identified on a weld drawing or other product engineering design document.

1.3 Usage. Welds are considered satisfactory when they meet the expected design service loads and satisfy functional performance requirements.The evaluation criteria contained in this document has been established as a basis for the manufacturing acceptance of welded products and are the same for all welds regardless of service load. Furthermore, welds identified as discrepant often retain a percentage of their mechanical properties and may contribute to the integrity of the welded product. Application of this specification for other uses, such as post-crash weld quality assessment, may lead to erroneous results or conclusions.1.4 Designation.

This material specification shall be referenced in other documents, drawings, VTS, CTS, etc. as follows:GM6435M

1.5 Clarification. For clarification of this specification or editorial comments, email the GM Weld Council at weld.council@https://www.360docs.net/doc/02422643.html, .

2 References

Note: Only the latest approved standards are applicable unless otherwise specified.2.1 Normative.AWS A2.4AWS A3.0ISO 104472.2 GM.EP-1GMN7027GM6122M

3 Requirements

3.1 General Acceptance Criteria.

3.1.1 Flash. Projection welded fasteners with threads shall be free of flash or spatter on the threaded sections. Fasteners that exhibit flash or spatter on the threaded section are nonconforming.

3.1.2 Presence and Location. Projection welded fasteners that are missing or located outside the position tolerance indicated on the assembly drawing are considered nonconforming.3.2 Visual Acceptance Criteria.

3.2.1 Cracks. Welded parts shall be free from detectable cracks within or around the welds.Parts which exhibit cracks in or around any welds are non-conforming.

3.2.2 Holes. Welded parts shall be free of holes or burn-throughs. Product that contain holes that extend through any of the welds or sheets are also nonconforming.

3.3 Measurable Acceptance Criteria.

GM6435M

GM ENGINEERING STANDARDS

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3.3.1 Weld Quality. A projection welded nut, stud,cage, or other part is acceptable when either the quantity of projections welded or push-out strength criteria are met. Projection welded parts that do not meet either of these two criteria are nonconforming.

3.3.2 Quantity of Projections Welded. A projection welded nut, stud, cage or other part is acceptable when the quantity of projections that show evidence of welding is equal to or greater than the number specified in Table 1. Evidence of welding exists when as a result of the fastener being separated from the parent metal, for each projection location a button or hole is torn from the parent metal, or if the measured post-weld projection height is greater than the pre-welded projection height (indicating that material transfer has occurred).

Table 1: Acceptable Weld Quantity Number of Projections on the

Part

Number of Projections with Evidence of

Welding

2132436

3.3.3 Push-out Load Strength Criteria. A projection welded nut, stud, cage or other part is acceptable when the tested part exceeds the push-out loads contained in Annex A.3.4 Process Adjustment Criteria.

3.4.1 Set-down. Weld fasteners and cages shall be set down so that the gap between the fastener/cage and the base part is no more than 0.6 mm. Fasteners and cages whose set-down exceeds this gap shall have the process adjusted.3.5 Product Conformance Criteria. Products supplied to the requirements of this standard are conforming provided the parts as welded meet the Acceptance Criteria of this standard. Parts not conforming to these criteria must be repaired or scrapped.

3.6 Repair Methods. Weld repair methods are shown in Appendix B. In the event a Weld Repair Data Sheet indicates a different method of repair,the Weld Repair Data Sheet must be followed.

3.7 Instructions.

3.7.1 The welding source is responsible for establishing practices and test methods to assure that the criteria of this standard are met. This includes weld verification procedures and process control. Methods for peel and chisel testing of resistance spot welds are contained in ISO 10447,“Welding – Peel and chisel testing of resistance spot, projection and seam welds.”

3.7.2 Inspection, measuring and test equipment to perform push-out load testing must be capable of evaluating the specified load to an accuracy of +/-100 Newtons. Parts being evaluated to the push-out load requirements of this document are to be mounted in such a way as to ensure that the applied loads are transferred through the welds of the joined parts. The push-out load must be applied normal to the plane of the attachment.

4 Notes

4.1 Glossary. Welding terms used in this specification shall be interpreted in accordance with the definitions provided in the latest edition of ANSI/AWS A3.0, Standard Welding Terms, and Definitions.

4.2 Acronyms, Abbreviations, and Symbols.The ANSI/AWS A2.4, Standard Symbols for Welding, Brazing, and Nondestructive Examination in conjunction with Appendix D of the NA Vehicle Structures and Closures Engineering Processes (EP-1) will be used to identify the type of welding employed for each joint.

5 Rules and Regulations

5.1 All materials supplied to this specification must comply with the requirements of GMW3001,Rules and Regulations for Material Specifications .

5.2 All materials supplied to this specification must comply with the requirements of GMW3059,Restricted and Reportable Substances for Parts .

5.3 Safety. Welding, cutting and allied processes can be performed safely with minimal health risk;provided proper procedures are followed and necessary 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.

GM ENGINEERING STANDARDS

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February 2002Page 3 of 6

5.2 Language. In the event of a conflict between the translated language and the English language,the English language shall take precedence.

6 Release and Revisions

6.1 Release. This specification was first approved and published in December 1996.

6.2 Revisions.Rev Date Description (Organization)

FEB 2002

Revised format, renumbered,complete revision, drawn arc welded steel nuts, and studs moved to GMN7027. (CRW)

GM6435M GM ENGINEERING STANDARDS Appendix A - Weld Nut And Stud Push-Off Load Requirements

WELD FASTENER SIZE MINIMUM PUSH-OUT LOAD

METRIC (mm)ENGLISH SIZES[ N ][Lbs]

4# 84,000899

5# 104,5001011

61/45,0001124

85/165,5001236

-3/87,0001574

10-7,0001574

-7/167,8001753

121/29,0002023

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GM ENGINEERING STANDARDS GM6435M

February 2002Page 5 of 6

Appendix B – Projection Welded Nut, Stud, Cage and Other Part Repair

Discrepant Condition

Description

GM6435M Reference

Method of Repair

Weld Flash

Fasteners that exhibit flash or spatter in the threaded section of the fastener.

Para. 3.1.1

Wire brush (for studs) or clean threads with a tap (for nuts)

Missing fastener (Part not painted)

Fasteners not installed.Para. 3.1.2Reprocess part and install projected welded fastener, or install fastener with GMAW fillet welds 1

on two opposite sides for square nuts, or with four fillet welds on two pair of opposite faces for hexagonal nuts, or with two fillet welds covering 90° circumference opposite each other for round headed fasteners, or with two 15mm long fillet welds on opposite sides of cages.

Missing fastener (Part is painted)

Fasteners not installed.Para. 3.1.2Prepare fastener location by grinding to remove paint. Install fastener with GMAW fillet welds 1

on two opposite sides for square nuts, or with fillet welds two pair of opposite faces for hexagonal nuts, or with two fillet welds covering 90° of the circumference opposite each other for round headed fasteners, or with two 15mm long fillet welds on opposite sides of cages. Re-paint after repair.

Mislocated fastener The fastener is located outside the position tolerance.

Para. 3.1.2Remove the mislocated fastener and grind as necessary to restore mating surface.Follow appropriate repair method for missing fastener.

Cracks or Holes (Part not painted)Cracks or holes are present.Para.3.2.1, 3.2.2Arc weld 1

so that the nonconforming condition is no longer present.

Cracks or Holes (Part is painted)

Cracks or holes are present.Para.3.2.1, 3.2.2Prepare fastener location by grinding to remove paint. Arc weld 1

so that the nonconforming condition is no longer present. Re-paint after repair.

Insufficient weld quantity or Inadequate Strength (Part is not painted)

Weld quality is insufficient.Para. 3.3.2, 3.3.3Add GMAW fillet welds 1

on two opposite sides for square nuts, or fillet welds on two pair of opposite faces for hexagonal nuts, or two fillet welds covering 90° of the

circumference opposite each other for round headed fasteners, or two 15mm long fillet welds on opposite sides of cages.

GM6435M GM ENGINEERING STANDARDS

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Insufficient weld quantity or Inadequate Strength

(Part is painted)

Weld quality is insufficient.Para. 3.3.2, 3.3.3Prepare fastener location by grinding to remove paint. Install fastener with GMAW fillet welds 1

on two opposite sides for square nuts, or fillet weld two pair of opposite faces for hexagonal nuts, or two fillets covering 90°of the circumference opposite each other for round headed fasteners, or two 15mm long fillet welds on opposite sides of cages. Re-paint after repair.

Note 1: GMAW repair welds must meet GM6122M acceptance criteria.