1、 WORLDWIDE ENGINEERING STANDARDS Test Procedure GMW15961 Fastened Joint Thermal Fatigue Testing Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 1 of 8 1 Scope Note: Nothing in this standard supercedes applicable laws and regulations. Note: In the event of conflict between th
2、e English and domestic language, the English language shall take precedence. 1.1 Purpose. To determine joint integrity when subjected to alternating loads induced by different thermal expansion rates of the dissimilar materials of the joint. 1.2 Foreword. To evaluate joint integrity, the test item s
3、hould complete 125 cycles while retaining at least 70% of its target (or initial) fastener tension. An alternate criteria would require that a cycle count and retained fastener tension percentage be specified by the test requestor. 1.3 Applicability. Unless otherwise specified, this procedure applie
4、s to the initial tightening event of joints using all new parts including threaded fasteners, bearing surfaces and clamped members 2 References Note: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. None 2.2 GM Standards/Specificati
5、ons. None 2.3 Additional References. Assembly Tool Manufacturers Operating Procedure Data Acquisition System Manufacturers Operating Procedure 3 Resources 3.1 Facilities. GM approved laboratory or location for this test procedure. 3.1.1 Calibration. The test facilities and equipment shall be in good
6、 working order and shall have a valid calibration label. 3.1.2 Alternatives. Alternative test facilities and equipment may also be used. However, all measuring variables as specified in this standard shall be determined correctly with respect to their physical definition. 3.2 Equipment. 3.2.1 Torque
7、 Angle Transducer. 3.2.2 Data acquisition system capable of collecting data at a sampling rate of at least 1000 Hz, plotting data at user specified scales, and identifying data at all points on the curve. 3.2.3 Tightening tool. 3.2.4 Appropriate fixtures, bedplate, or slotted table. 3.2.5 Strain ind
8、icator (if applicable). 3.2.6 Strain gauged fastener or fastener prepared for ultrasonic measurement. 3.2.7 Environmental Test Chamber (with air and part temperature control). The chamber should be programmable and be able to cycle part temperature from -40 C to +155 C. Set temperatures must be capa
9、ble of being maintained within 3 C. Alternate chamber capability may be specified or approved by the test requestor. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWI
10、DE ENGINEERING STANDARDS GMW15961 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 2 of 8 3.3 Test Vehicle/Test Piece. A complete bill of materials of required test pieces will be specified in the test request documentation. Note: Unless otherwise specified, a minimum of eigh
11、t samples are to be used for this procedure. 3.4 Test Time. Calendar time: 30 days Test hours: 120 hours Coordination hours: 40 hours 3.5 Test Required Information. Test request documentation shall outline specific information and test parameters. Reference Appendix A or use similar format. 3.6 Pers
12、onnel/Skills. Test Technician shall be qualified on the basis of appropriate education, training, experience, and/or demonstrated skills. 4 Procedure 4.1 Preparation. Unless otherwise specified in the test request, samples are to be tested in the as-received condition. This excludes any condition sp
13、ecifically caused by material storage or configuration (e.g., if debris falls into a threaded hole from laboratory rework, it is acceptable to blow debris out of holes). 4.1.1 Any modifications to parts, not specifically requested in the test request that may affect test results, are to be documente
14、d in the test notes. All test configurations, parts and noted deviations to be approved by the test requestor prior to executing test. 4.2 Conditions. 4.2.1 Environmental Conditions. Not applicable. 4.2.2 Test Conditions. Deviations from the requirements of this standard shall have been agreed upon.
15、 Such requirements shall be specified on component drawings, test certificates, reports, etc. 4.3 Instructions. 4.3.1 Review part quantities and condition. 4.3.2 Secure test part to T-slot table or fixture. 4.3.3 Select proper tool, strain-gauged fastener or fastener prepared for ultrasonic measurem
16、ent, and torque-angle transducer. 4.3.4 If applicable, configure ultrasonic measurement device to capture initial L-Ref (length reference) values. 4.3.5 Configure tooling to reproduce requested tightening strategy of the fastener. Refer to Assembly Tool Manufacturers Operating Procedure. 4.3.6 Align
17、 tool and torque-angle transducer to prevent side loading. 4.3.7 Tighten the test item to the requested tightening strategy, recording torque, tension, and angle. Refer to Data Acquisition System Manufacturers Operating Procedure. Review with requestor and receive approval prior to proceeding. 4.3.8
18、 Continue tightening any remaining test items or joints as outlined in test request documentation. 4.3.9 Mark fastener locations with paint pen or other agreed-upon method (on head and bearing surface) for future rotation checks. 4.3.10 Place test item(s) in environmental chamber. 4.3.11 Attach cham
19、bers part temperature control device to the test piece in a location approved by the test requestor. 4.3.12 Configure thermal chamber to cycle test item(s) with part temperature control as follows: Ramp to -40 C 3 C Hold for 10 minutes Ramp to +155 C 3 C Hold for 30 minutes Ramp to -40 C 3 C Copyrig
20、ht 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 GMW15961 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 3 of 8 or follow
21、a chamber program as specified by the requestor. Times may vary based on size and mass of part. 4.3.13 Record fastener tension at specified intervals during testing according to the following criteria: 4.3.13.1 Fastener tension is to be recorded at 0, 10, 25, 50, 75, 100, and 125 End of Test (E.O.T.
22、) cycles or at a cycle count series as specified by the requestor. 4.3.13.2 Before recording fastener tension, ramp the chamber air temperature to +21 C 3 C (ambient) and hold for a time period sufficient to ensure stabilization of test part temperature. 4.3.13.3 Record fastener tension at ambient t
23、emperature before proceeding to next temperature cycle. 4.3.13.4 Inspect for fastener rotation at 10, 25, 50, 75, 100 and 125 E.O.T. cycles, or at a cycle count series as specified by the requestor. If rotation is observed, notify and record location and amount. 4.3.13.5 Summarize all test results a
24、ccording to the requirements of Section 5. 5 Data 5.1 Calculations. Not applicable. 5.2 Interpretation of Results. Not applicable. 5.3 Test Documentation. 5.3.1 Summary of Results Required. 5.3.1.1 Provide statistical analysis of maximum installed torques and tensions. Calculate averages, minimum va
25、lues, maximum values, and standard deviation. 5.3.1.2 Provide detail of failure modes consisting of, but not limited to, fastener fracture, component fracture, component distortion or internal or external thread stripping (if applicable). 5.3.1.3 Test incidents to be recorded on Fastener Test Data S
26、ummary Sheet. Reference Appendix B or use similar format. 5.3.1.4 Test data summarization to be on Test Data Log Sheet. Reference Appendix C or use similar format. 5.3.2 Summary of Results Optional. After reviewing required data summarization, the requestor may ask for additional items including, bu
27、t not limited to, optional plots and tabular data tables as shown in Table 1. 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 GMW15961 Copyr
28、ight 2013 General Motors Company All Rights Reserved July 2013 Page 4 of 8 Table 1: Optional Plots and Tabular Data X-Axis Y-Axis TorqueTensionAngle CompressionLoadDisplacementRPM TimeTorque DIT10M Tension Angle Compression Load Displacement RPM DIM Legend: I = Individual sample plots. D = Dual Y ax
29、is plots. M = Multiple sample plot. S = Statistical plot. T = Tabular data table, followed by the incremental value. 5.3.2.1 Magnified Scale Plots. Additional plots re-scaled to magnify desired detail of curves. 6 Safety This standard may involve hazardous materials, operations, and equipment. This
30、standard does not propose to address all the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 7 Notes 7.1 Glossary. Failure Modes
31、: This may consist of, but are not limited to, fastener fracture, component fracture, component distortion, or internal or external thread stripping. Fracture is defined as the partial or complete separation of one or more of the joint components. Fastener Tension: Force normal to the mating surface
32、s of the joint provided by the fastener. Test Request Documentation: Forms outlining specific requirements, procedures, and desired results of laboratory test to be performed. Thermal Chamber: Programmable chamber capable of thermally cycling test items from -40 C to +155 C. 7.2 Acronyms, Abbreviati
33、ons, and Symbols. CCW Counterclockwise CW Clockwise E.O.T. End of Test Hz Hertz L-Ref Length reference Nm Newton meter RPM Revolutions per minute Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without li
34、cense from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15961 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 5 of 8 8 Coding System This standard shall be referenced in other documents, drawings, etc., as follows: Test to GMW15961 9 Release and Revisions This standard was
35、originated in May 2008. It was first approved by the Global Fastening & Sealing Test Lab Expert Team in August 2008. It was first published in August 2008. Issue Publication Date Description (Organization) 1 AUG 2008 Initial publication. 2 JUL 2013 Five year refresh of standard. Revised wording in P
36、aragraphs 1.3 and 4.3.13.3. Revision to Appendix A, Line 3 to replace Production Assembly Document (PAD) with Master Process Document. Added Appendix references in Paragraphs 3.5, 5.3.1.3 and 5.3.1.4. (Fastening & Sealing Test Lab Global Subsystem Leadership Team) Copyright General Motors Company Pr
37、ovided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15961 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 6 of 8 Appendix A Data Sheet A1: Test Require
38、d Information Worksheet Test Title: Model Year/Program: Test Request Number: Requestor/Phone: Part Number Quantity Description Fastener Diameter Fastener Grade Or Class Fastener Pitch 1. Part Disposition at Completion: 2. Required Completion Date: 3. Master Process Document or Diagram Attached? Y or
39、 N If Yes, number 4. Tightening Sequence Required. Y or N (If Yes, attach diagram) 5. Number and Orientation of Tool Spindles: (Attach diagram if necessary) 6. Tool Type: 7. Tool Free Spinning Speed: RPM Maximum Torque: Nm 8. Tool Downshift: Y N (If Yes, Downshift Parameter Downshift Free Speed 9. T
40、ool Rotation: Clockwise (CW) Counterclockwise (CCW) 10. Tool Trigger: Torque Nm Angle Degrees 11. Requested Tightening Specification If applicable: _ Nm To Fail? Y N 12. Current Tightening Specification If applicable: _ Nm To Target? _ Nm 13. Test Piece Orientation: _ (Attach diagram if necessary) 1
41、4. Test Coupon Used? Y N, If Yes, drawing or sketch required Test Matrix Step No. Description 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 STANDARD
42、S GMW15961 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 7 of 8 Appendix B Data Sheet B1: Fastener Test Data Summary Sheet Start Date: Test Engineer: Page of End Date: Technician: Test Request Number: Location: Sequence Number: File Name: Location: File Type: Mc900 Boltmik
43、e Megadac Test Title: Others: Test Description: Torqued Member: Clamped Member: Bearing Surface: Stationary Member: Sample Number Date Operator Comments Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted wit
44、hout license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15961 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 8 of 8 Appendix C Data Sheet C1: Test Data Log Sheet Fastener Test File Log and Summary Page of Test Title: Test Request Number Date Test Location Requestor Technician Sample Hz Filter Hz Comments Date File Name Comments Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
