1、 WORLDWIDE ENGINEERING STANDARDS Material Specification GMW14085 Acceptance Criteria and Repair Procedures Mechanical Clinch Joining Copyright 2013 General Motors Company All Rights Reserved May 2013 Page 1 of 6 1 Scope This standard addresses mechanical clinch joining of steel to steel, steel to al
2、uminum and aluminum to aluminum. Note: Nothing in this standard supercedes applicable laws and regulations. Note: In the event of conflict between the English and domestic language, the English language shall take precedence. 1.1 Purpose. This standard provides the acceptance criteria and repair pro
3、cedure for circular mechanical clinches in automotive products for which GM is responsible for establishing or approving the product design. 1.2 Applicability. The criteria established in this specification become mandatory when referenced on a weld or assembly drawing. Deviation from any criteria p
4、rovided in this specification must be identified on a weld design document or other product engineering design document. 1.3 Usage. Clinches are considered satisfactory when they meet the expected design service loads and satisfy functional performance requirements. The evaluation criteria contained
5、 in this document have been established as a basis for the manufacturing acceptance of clinched products and are the same for all clinches regardless of service load. Furthermore, clinches identified as discrepant often retain a percentage of their mechanical properties and may contribute to the int
6、egrity of the clinched product. Application of this specification for other uses, such as post-crash clinch quality assessment, may lead to erroneous results or conclusions. 1.4 Clarification. For clarification of this specification or editorial comments, email the GM Global Weld Council at . Propos
7、ed changes to this standard must be presented to the GM Weld Council. To suggest a change to this standard, reference the “Procedure for Weld Standard Changes” on the Weld Councils webpage. 2 References Note: Only the latest approved standards are applicable unless otherwise specified. 2.1 External
8、Standards/Specifications. None 2.2 GM Standards/Specifications. GMW14057 GMW15563 GMW14058 2.3 Additional References. Global Weld Council web page: https:/ 3 Requirements 3.1 General Acceptance Criteria. 3.1.1 Categories of Clinches. There are two categories of mechanical clinches: Structural Clinch
9、es and Process Clinches. 3.1.1.1 Structural Clinches. Structural clinches are required for performance of the clinched product. All clinches are structural unless noted as process clinches on the weld design document. Structural clinches shall be evaluated to the requirements of 3.1.2, 3.2.1, 3.3.1
10、and 3.3.2 of this specification. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14085 Copyright 2013 General Motors Company All Rights R
11、eserved May 2013 Page 2 of 6 3.1.1.2 Process Clinches. Process clinches facilitate in-process assembly but are not required for structural performance of the product. Process clinches must be approved and identified on the weld design document by Product Engineering. Process clinches shall be evalua
12、ted to the requirements of paragraph 3.1.2 of this specification. 3.1.2 Presence and Location. Clinches that are missing or placed outside the location tolerance indicated on the weld design document drawing are discrepant. If no location tolerance is specified, clinches may be located up to 10 mm f
13、rom the position shown on the weld design document. 3.2 Visual Acceptance Criteria. 3.2.1 Cracks. Steel to steel clinches must not have any cracks in or around the clinch which are visible without the aid of magnification. Clinches which exhibit visible cracks in or around any clinches are discrepan
14、t. Steel to aluminum or aluminum to aluminum clinch crack acceptance criteria to be documented in either the product Statement of Requirements or on an approved Product Quality Standard (PQS). 3.2.2 Visual Appearance of Clinch. If the surface around the clinch appears distorted due to mis-alignment
15、of the clinch tooling to the sheet metal, the process must be adjusted to correct the distortion. 3.3 Measurable Acceptance Criteria. (Examples of measurement techniques can be seen in Figures A1 and A2 in Appendix A.) 3.3.1 Size. A clinch whose measured dimensions are within the specified range (de
16、termined from testing of the specified materials and thicknesses) is an acceptable clinch. The bottom thickness measurement (dimension C2 in Figure 1) and the button diameter (dimension C1 in Figure 1) are both to be measured to determine clinch acceptance. The acceptable specified measurement range
17、 is to be recorded on the Clinch Tool Data Sheet. Clinches which are outside the acceptable range are discrepant. Figure 1: Clinch Weld Size Measurements 3.3.2 Edge Distance. The specified clinch button diameter must be contained within all edges of the sheet metal. A clinch is discrepant if the dis
18、tance between the edge of the button and any edge of the sheet metal is less than the total material thickness of the joint. 3.3.3 Cross-Section Analysis. Cross-sectional analysis is required when there is an unresolved acceptance criteria issue. A typical mechanical clinch cross section is shown in
19、 Figure A3. 3.3.4 Test Coupon Strength. When the clinch test coupon strength (peel and/or shear strength) is less than 85% of the value established by the equipment manufacturer, the process must be adjusted to increase the strength of clinch test coupons to a minimum of 90% of the initial establish
20、ed value. 3.4 Disposition/Repair Procedure. 3.4.1 Clinch Pattern Conformance Criteria. A pattern is a collection of clinches to which a tolerance is applied to meet structural requirements and for determining manufacturing acceptance of the product. Clinch patterns must include all structural clinch
21、es and be shown on the weld design document. Process clinches shall not be included in any clinch patterns. The clinch pattern is conforming when the number of acceptable clinches (not discrepant per the requirements of paragraphs 3.1.1, 3.2 and 3.3 of this specification) within a pattern meets or e
22、xceeds the pattern tolerance Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14085 Copyright 2013 General Motors Company All Rights Reser
23、ved May 2013 Page 3 of 6 as stated on the weld design document. Manufacturing acceptance of product is based on all patterns conforming. Known and suspect product with nonconforming patterns must be repaired. 3.4.2 Repair Methods. Clinch repair methods are shown in Appendix B. In the event a Clinch
24、Repair Data Sheet indicates a different method of repair, the Clinch Repair Data Sheet must be followed. 4 Manufacturing Process 4.1 Process Control. The source is responsible for establishing practices and test methods to assure that the criteria of this standard are met, and are consistent with th
25、e GM Joining and Dispense Process Control Procedure (e.g., GMW15563). 5 Notes 5.1 Glossary. Not applicable. 5.2 Acronyms, Abbreviations, and Symbols. CTS Component Technical Specs PQS Product Quality Standard SKM GME Specification Design Mechanics SKR GME Specification Design Mechanics VTS Vehicle T
26、echnical Specifications 6 Coding System This standard shall be referenced in other documents, drawings, etc., as follows: GMW14085 7 Release and Revisions This standard was originated in January 2005. It was first approved by the CCRW Global Council in April 2007. It was first published in April 200
27、7. Issue Publication Date Description (Organization) 1 APR 2007 Initial publication. 2 OCT 2010 Corrected an error in the original publication as well as two editorial changes. (Global Weld Council) 3 MAY 2011 Corrected 3.3.2 reference to Figure A3. (Global Weld Council) 4 OCT 2012 Aluminum crack ac
28、ceptance criteria clarification. Evaluation criteria for clinch size revised. (Global Weld Council) 5 MAY 2013 Revised paragraph 3.3.4. (Global Weld Council) Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitte
29、d without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14085 Copyright 2013 General Motors Company All Rights Reserved May 2013 Page 4 of 6 Appendix A: Measurement Figure A1: Bottom Thickness Measurement Figure A2: Button Measurement Copyright General Motors Company Provided by IHS und
30、er license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14085 Copyright 2013 General Motors Company All Rights Reserved May 2013 Page 5 of 6 A Total sheet thickness B Sheet thickness on the stamp s
31、ide C Internal diameter of joint element D Depth of penetration E Undercut F Thickness of sheet metal web on the stamp side G Thickness of sheet metal web on the die side H Residual base thickness I External diameter of joint element J Sheet thickness on the die side K Degree to which point is raise
32、d Figure A3: Typical Clinch Section Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14085 Copyright 2013 General Motors Company All Right
33、s Reserved May 2013 Page 6 of 6 Appendix B: Repair Methods Table B1: Mechanical Clinch Repair Methods Discrepant Condition Description GMW14085 Reference Repair Method Missing clinch Clinch is not installed. 3.1.2 Manually install clinch Note 1 in specified location, install blind (“pop”) rivet, or
34、use repair methods specified in GMW14057 (only for steel to steel). Review and approval by responsible Product Engineer is required. Mislocated clinch The clinch is located outside the position tolerance. 3.1.2 Manually install additional clinch Note 1 in specified location, install blind (“pop”) ri
35、vet, or use repair methods specified in GMW14057 (only for steel to steel). Review and approval by responsible Product Engineer is required. Cracks Visible cracks are present in or around the clinch. 3.2.1 Arc weld Note 2 (only for steel to steel or aluminum to aluminum) so that the condition is no
36、longer present. Insufficient clinch size Clinch button diameter or bottom thickness measurement is outside specified tolerance range. 3.3.1 Manually install additional clinch Note 1 within 20 mm of specified location, install blind (“pop”) rivet, or use repair methods specified in GMW14057 (only for
37、 steel to steel). Review and approval by responsible Product Engineer is required. Insufficient edge distance Clinch is too close to the edge of, or not fully contained within, the sheet metal. 3.3.2 Manually install additional clinch Note 1 within 20 mm of specified location, install blind (“pop”)
38、rivet, or use repair methods specified in GMW14057 (only for steel to steel). Review and approval by responsible Product Engineer is required. Note 1: Manual repair clinches must meet the requirements of this specification. Note 2: Arc weld repairs must meet the requirements of GMW14058 for steel or regional aluminum arc welding standard for aluminum. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
