1、 WORLDWIDE ENGINEERING STANDARDS Test Procedure GMW14676 Compression Properties of Metal Center Tubes and Contact Surfaces of Metal Parts with Bolt Through Holes Copyright 2012 General Motors Company All Rights Reserved November 2012 Originating Department: North American Engineering Standards Page
2、1 of 8 1 Scope 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 test procedure shall be used to determine the compression properties of me
3、tal center tubes and contact surfaces of metal parts with bolt through holes. 1.1.1 Definition. The compression properties of metal center tubes and contact surfaces of metal parts with bolt through holes as determined by this test procedure shall be defined as the permanent length change of a part
4、mentioned previously, when subjected to an axial pressure applied at a fixed velocity. The compression properties can be expressed by a force-displacement hysteresis curve. 1.2 Foreword. Not applicable. 1.3 Applicability. Not applicable. 2 References Note: Only the latest approved standards are appl
5、icable unless otherwise specified. 2.1 External Standards/Specifications. ISO 898-2 ISO 898-6 ISO 9513 ISO 7500-1 2.2 GM Standards/Specifications. GMW15011 3 Resources 3.1 Facilities. Not applicable. 3.2 Equipment. 3.2.1 Universal testing machine capable of stressing center tubes to a force at a con
6、stant velocity of 10 mm/minute maximum test forces according to 4.3.2 of this procedure. 3.2.1.1 The testing machine shall comply with ISO 9513 and ISO 7500-1, Sheet 1. The testing machine shall also comply with the following requirements: Total accuracy of the force measuring equipment 1% of the me
7、asured value. Displacement measuring equipment: 0.01 mm. If possible, the displacement measuring device should be mounted so that it measures directly across the test part. Fixturing deflection may be erroneously interpreted as test part deflection if care is not taken during the setup. The measurin
8、g instruments shall function with a low moment of inertia. 3.2.2 Coordinate recorder (x-y recorder) or similar data acquisition software which records the force-displacement characteristics of the part. The reading accuracy of the compiled diagram shall be 0.01 mm minimum for displacement 1 cm 0.1 m
9、m. The gradient of the curve shall be in a range of 20 to 45 degrees. 3.2.2.1 Optional. Digital recording device for simultaneous recording of load and displacement. 3.2.3 A test jig, consisting of two plane, parallel tool steel plates, between which the center tubes shall be loaded. To avoid measur
10、ing errors, the device shall be as rigid as possible. Test plates should be sufficiently hardened to not allow embedment within test load range. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without lic
11、ense from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14676 Copyright 2012 General Motors Company All Rights Reserved November 2012 Page 2 of 8 3.3 Test Vehicle/Test Piece. Samples shall be tested to the criteria outlined in 4.3.2 of this document unless otherwise specified by the part drawing, Ve
12、hicle Technical Specification, Subsystem Technical Specification, Component Technical Specification or specified standard. 3.4 Test Time. Not applicable. 3.5 Test Required Information. Test request documentation should outline specific test data requirements. Data should be reported in format simila
13、r to what is contained in Appendix A. 3.6 Personnel/Skills. Not applicable. 4 Procedure 4.1 Preparation. Not applicable. 4.2 Conditions. 4.2.1 Environmental Conditions. The test shall be performed at +23 C 5 C. 4.2.2 Test Conditions. Deviations from the requirements of this standard shall have been
14、agreed upon. Such requirements shall be specified on component drawings, test certificates, reports, etc. 4.3 Instructions. 4.3.1 The part shall be installed so that the following conditions are met: The direction of the force shall run axially. During loading, there shall be no misalignment which m
15、ay result in measuring errors. 4.3.2 Using the strain rate specified in 3.2, the part shall be subjected to the maximum force Fa (refer to Table 1 and Table 2). This force shall then be reduced to give 50% of the maximum force Fm. Stress for steel center tubes corresponds to the test force for nut t
16、hread according to: ISO 898-2 for coarse thread. ISO 898-6 for fine thread. 4.3.3 The permanent compression shall be taken from the resulting force-displacement curve. 4.3.4 Photograph the test setup and the test parts after test. An example of a test setup is shown in Figure 1. Figure 1: Example of
17、 Test Setup 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 GMW14676 Copyright 2012 General Motors Company All Rights Reserved November 2012
18、 Page 3 of 8 Table 1: Maximum Force Fa for Coarse Thread (Values Rounded) Thread Dimension Fastening Screw for Bolted Joints of Steel Center Tubes Property Class 8.8 10.9 12.9 Property Class for Nut 8 10 12 M8 32 kN 38 kN 42 kN M10 51 kN 60 kN 66 kN M12 74 kN 89 kN 99 kN M14 101 kN 121 kN 135 kN M16
19、 138 kN 165 kN 184 kN M18 177 kN 204 kN 230 kN* M20 225 kN 260 kN 294 kN* Table 2: Maximum Force Fa for Fine Thread (Values Rounded) Thread Dimension Fastening Screw for Bolted Joints of Steel Center Tubes Property Class 8.8 10.9 12.9 Property Class for Nut 8 10 12 M8x1 37 kN 43 kN 47 kN M10x1.25 58
20、 kN 67 kN 73 kN M12x1.5 84 kN 98 kN 106 kN M14x1.5 119 kN 139 kN 150 kN* M16x1.5 160 kN 185 kN 200 kN* M18x1.5 222 kN 232 kN* - M20x1.5 280 kN 294 kN* - 5 Data 5.1 Calculations. 5.1.1 The compression properties of the parts shall be determined from the force-displacement curve. 5.1.2 The force-displ
21、acement curve (see Figure 2). 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 GMW14676 Copyright 2012 General Motors Company All Rights Rese
22、rved November 2012 Page 4 of 8 Figure 2: Force-Displacement Curve Fa Maximum force Fm 2 forceM axim um s Permanent compression at Fm The graph shows a force-displacement curve of a part loaded to the specified maximum stress (Fa). The permanent compression amount is the change in length of the part
23、measured at 50% of the maximum force after loading and unloading. 5.2 Interpretation of Results. The permissible permanent compression shall be: 0.15 mm for a grip length of 30 mm. 0.5% of the compression length for a grip length of 30 mm. 5.2.1 Test incidents to be recorded on test data summary she
24、et similar to Appendix B. 5.2.2 Test data summarization to be on test data log sheet similar to Appendix C. 5.3 Test Documentation. With reference to this test procedure, the results shall be represented in a test report. 6 Safety This standard may involve hazardous materials, operations, and equipm
25、ent. This 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. Not
26、 applicable. 7.2 Acronyms, Abbreviations, and Symbols. MPD Master Process Document 8 Coding System This standard shall be referenced in other documents, drawings, etc., as follows: Test to GMW14676 Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for Resa
27、leNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14676 Copyright 2012 General Motors Company All Rights Reserved November 2012 Page 5 of 8 8.1 For Steel Parts (Example). Compression Properties to GMW14676 - Screw M10, Property Class 10.9, C
28、lamping Length 71 mm. Compression Properties = Designation GMW14676 = Test Method Screw M10 = Test screw 8.2 For Aluminum Parts. Coding according to GMW15011. 9 Release and Revisions This standard was originated in October 2005. It was first approved by the Fastening and Sealing Test Lab GSSLT repre
29、sentatives in December 2006. It was first published in March 2007. Issue Publication Date Description (Organization) 1 MAR 2007 Initial publication. 2 NOV 2012 Five year refresh of standard. Revised note on jig material hardness, 3.2.3. Changed data reporting requirements to be similar to Appendix f
30、ormat. (Fastening and Sealing Test Lab GSSLT) 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 GMW14676 Copyright 2012 General Motors Company
31、 All Rights Reserved November 2012 Page 6 of 8 Appendix A: Test Required Information Worksheet Project: Name: _ Model Year/Program: _ Request No: Requestor/Phone: Part Number Quantity Description 1. Part Disposition at Completion: _ 2. Required Completion Date: _ 3. Master Process Document or Diagra
32、m Attached? Y N If Yes, MPD Number:_ 4. Maximum Requested Load If Applicable: _ _ kN 5. 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 o
33、r networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14676 Copyright 2012 General Motors Company All Rights Reserved November 2012 Page 7 of 8 Appendix B: Test Data Summary Sheet Start Date: Test Engineer: Page of End Date: Technician: Test Request No: Location:
34、File Name: Location: File Type: Mc900 Megadac Test Title: Test Description Sample Number: Comments: 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 ST
35、ANDARDS GMW14676 Copyright 2012 General Motors Company All Rights Reserved November 2012 Page 8 of 8 Appendix C: Test Data Log Sheet Fastener Test File Log and Summary Page _ of _ Test Title: Test Request No. Date Test Location Requestor Technician Sample Hertz Filter Hertz 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-,-,-
