1、 WORLDWIDE ENGINEERING STANDARDS Test Procedure GMW15930 Torque, Tension, Angle Evaluation of U-bolted Joints Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 1 of 13 1 Scope Note: Nothing in this standard supercedes applicable laws and regulations. Note: In the event of conf
2、lict between the English and domestic language, the English language shall take precedence. 1.1 Purpose. To determine the dynamic torque, tension, and angle characteristics of a U-bolted joint. 1.2 Foreword. 1.2.1 Limitation. This procedure does not apply to Pulse tools. 1.2.2 Unless otherwise speci
3、fied, any requirements or direction provided in the Test Request documentation will supercede this test procedure. 1.3 Applicability. Unless otherwise specified, this procedure applies to the initial tightening event of joints using threaded fasteners with new thread and bearing surfaces and new cla
4、mped members. 2 References Note: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. None 2.2 GM Standards/Specifications. GMW15569 GMW16820 3 Resources 3.1 Facilities. GM approved laboratory or location for this test procedure. 3.1.1
5、Calibration. The test facilities and equipment shall be in good 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 re
6、spect to their physical definition. 3.2 Equipment. 3.2.1 Torque/angle transducers (two per U-bolt). 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 Strain g
7、aged U-bolts. 3.2.4 Tightening tools (two per U-bolt). 3.2.5 Load frame. 3.2.6 Strain indicator. 3.2.7 Appropriate fixturing, bedplate, or slotted table. 3.3 Test Vehicle/Test Piece. 3.3.1 A complete bill of materials of required test pieces will be specified in the Test Request documentation. 3.3.2
8、 Unless otherwise specified, a minimum of four joints are to be used for this test. 3.3.3 Typical component quantities may be: 3.3.3.1 Anchor plates: 4. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted wit
9、hout license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15930 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 2 of 13 3.3.3.2 Spacers: 4. 3.3.3.3 U-bolts: 14. 3.3.3.4 Axles with spring seat: 4. 3.3.3.5 Leaf spring: 1. 3.3.3.6 Nuts and washers: 20. 3.4 Test Time. Cale
10、ndar time: 4 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 B, Data Sheet B1, or use similar format). 3.6 Personnel/Skills. Test Technician shall be qualified
11、 on the basis of appropriate education, training, experience, and/or demonstrated skills. 4 Procedure Note: Any deviations to this procedure are to be entered in the Test Notes or Log Sheets. 4.1 Preparation. 4.1.1 U-bolt Load Deflection Test. 4.1.1.1 In order to establish a calibration value for st
12、rain gaged U-bolts, randomly select two U-bolts. 4.1.1.1.1 Perform U-bolt Saddle Tensile Test in accordance with GMW16820 while recording load and deflection. 4.1.1.1.2 Supply load vs. deflection curve. 4.1.1.1.3 Core hardness check (optional) can be also performed. 4.1.1.2 Select Calibration Load f
13、rom saddle tensile plot. Note: Plot depicts total load. Divide by two to obtain tensile load per U-bolt leg. Curve should be linear up to desired calibration load per U-bolt leg. 4.1.2 U-bolt Strain Gaging and Calibration. 4.1.2.1 Randomly select eight U-bolts and attach the required strain gages, f
14、ull bridge wired for axial loading with bending compensation. Reference U-bolt schematic for location of strain gages (Figure A1). 4.1.2.2 Install a U-bolt into the load frame using the load frame fixturing. 4.1.2.3 To ensure the U-bolt is centered on the fixture, run the two threaded adapters down
15、evenly until adequate engagement (minimum one U-bolt diameter from first full thread) is achieved. 4.1.2.3.1 If possible, the adapters should not be placed in the area where the nuts will reside upon final assembly. 4.1.2.3.2 The threads used to achieve the correct clamp should remain virgin. This i
16、s desirable because any change in the surface finish of the thread could affect the coefficient of friction. 4.1.2.4 Exercise the U-bolt by loading it to maximum calibration value and returning to zero load a minimum of three times. 4.1.2.5 Remove zero offset from strain gage if necessary. 4.1.2.6 M
17、easure strain gage output and calibration load cell values in at least five equally spread increments, from zero load to maximum calibration value, and from maximum value back to zero. 4.1.2.7 Repeat 4.1.2.6 two more times and average the data. 4.1.2.8 If calibration error is less than or equal to 2
18、.5% full scale, document the sensitivity, shunt calibration resistance, shunt calibration load values, excitation voltage and zero output voltage. 4.1.2.9 If calibration error is greater than 2.5%, repeat 4.1.2.5 through 4.1.2.7 until error of less than or equal to 2.5% is achieved. 4.1.2.10 If unab
19、le to satisfy calibration requirements within three calibration cycles, contact the 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 WORLDWIDE ENGINEERING STANDAR
20、DS GMW15930 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 3 of 13 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. Such requirements shall be specified on c
21、omponent drawings, test certificates, reports, etc. 4.3 Instructions. 4.3.1 Review part quantities and condition. 4.3.2 Secure test parts to T-slot table or fixture. 4.3.3 Select tightening tools and mount them in the tool holding fixture. 4.3.4 Synchronize all tools to tool speed requested and docu
22、ment free spinning speed. 4.3.5 Select strain gaged U-bolts and torque transducers with angle encoders. 4.3.6 Configure data acquisition system to collect torque, tension, and angle data for each spindle. 4.3.7 Obtain test parts and loosely assemble them (i.e., no load on U-bolts until after calibra
23、tion check). 4.3.8 Record calibration signal from instrumented U-bolts (no load applied). 4.3.9 (Optional). Apply minimum torque to all nuts in order to bring assembly together in a uniform manner and visually inspect to ensure that thread protrusion is approximately equal. 4.3.10 Unless otherwise s
24、pecified, test requestor is to approve the test setup. 4.3.11 Using multi-spindle setup, simultaneously torque nut on each U-bolt leg. 4.3.12 Joint shall be tightened to the specifications outlined in Test Request documentation. Test shutoff parameters may include but are not limited to: 4.3.12.1 Ma
25、ximum U-bolt calibrated load. 4.3.12.2 Maximum tightening specification target. 4.3.12.3 Joint failure. 4.3.13 Unless otherwise specified, run the first sample recording torque, tension, angle, and failure mode, if any. 4.3.13.1 Visually inspect the joint for deformation, fracture, etc. 4.3.13.2 Rev
26、iew findings with requestor and receive approval prior to proceeding. 4.3.14 If necessary, adjust the test configuration to comply with instructions of requestor. 4.3.15 (Optional). After each test, conduct an audit torque (reference GMW15569). 4.3.15.1 For tightening sequence, refer to appropriate
27、Master Process Document. 4.3.15.2 Record data on Data Sheet C1 or use similar format. 4.3.16 Complete the test matrix on Data Sheet C1 or use similar format. 4.3.17 Summarize results according to requirements in Section 5 of this procedure. 4.3.18 Take photographs or digital images of test setup. 5
28、Data 5.1 Calculations. Not applicable. 5.2 Interpretation of Results. 5.2.1 Summary of Results (Required). 5.2.1.1 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).
29、5.2.1.2 Test incidents to be recorded on Data Sheet C1 or use similar format. 5.2.1.3 Test data summarization to be recorded on Data Sheet D1 or use similar format. 5.2.1.4 Torque tension data summarization to be recorded on Data Sheet E1 or use similar format. 5.2.1.5 Required plots and tabular dat
30、a tables include items 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 GMW15930 Copyright 2013 General Motors Company All
31、Rights Reserved July 2013 Page 4 of 13 Table 1: Required Plots and Tabular Data Tables X-Axis Y-Axis TorqueTensionAngleCompressionLoadDisplacementRPM TimeTorque - T5- - - - - - Tension M - - - - - - - Angle - - - - - - - - Compression - - - - - - - - Load - - - - - - - - Displacement - - - - - - - -
32、 RPM - - - - - - - - Legend: I Individual sample plots (all spindles for each sample). L Individual spindle (leg) plot. M Multiple sample plot. S Statistical plot. T Tabular data table followed by the incremental value. D Dual Y Axis. 5.2.2 Summary of Results (Optional). After reviewing required dat
33、a summarization, requestor may ask for additional items including, but not limited to, the following: 5.2.2.1 Summary of results including, but not limited to, maximum torques, ultimate torques, and prevailing torques are recorded on Data Sheets F1 and/or G1 or use similar format. 5.2.2.2 Optional p
34、lots and tabular data tables include items shown in Table 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 GMW15930 Copyright 2013 General
35、 Motors Company All Rights Reserved July 2013 Page 5 of 13 Table 2: Optional Plots and Tabular Data Tables X-Axis Y-Axis TorqueTensionAngleCompressionLoadDisplacementRPM TimeTorque - - D,D,L,T10- - - - - - Tension I,S- D,L,T1- - - - - - Angle - - - - - - - - Compression - - - - - - - - Load - - - -
36、- - - - Displacement - - - - - - - - RPM - - - - - - - - Legend: I Individual sample plots (all spindles for each sample). L Individual spindle (leg) plot. M Multiple sample plots. S Statistical plot. T Tabular data table, followed by the incremental value. D Dual Y Axis. 5.2.2.3 Magnified scale plo
37、ts which are additional plots rescaled to magnify desired detail of curves. 5.3 Test Documentation. Use Data Sheets B1 thru G1 or similar format. 6 Safety This standard may involve hazardous materials, operations, and equipment. This standard does not propose to address all the safety problems assoc
38、iated 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: May consist of, but are not limited to, fastener fracture, compo
39、nent fracture, component distortion or internal or external thread stripping. Fracture: Partial or complete separation of one or more of the joint components. Maximum Torque: Maximum torque value observed during testing of the joint. Prevailing Torque: Maximum torque value observed while rotating th
40、e fastener prior to contacting the clamped member of the joint. 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 GMW15930 Copyright 2013 Gene
41、ral Motors Company All Rights Reserved July 2013 Page 6 of 13 Sensitivity: The ratio of the change in voltage output to the change in mechanical input. Test Request Documentation: Forms outlining specific requirements, procedures, and desired results of laboratory test to be performed. Ultimate Torq
42、ue: Maximum torque the joint can tolerate prior to fracture, deformation or strip. Zero Angle Reference Torque: Torque value at which the angle of all samples recorded is set to zero for analysis purposes. 7.2 Acronyms, Abbreviations, and Symbols. CCW Counterclockwise CW Clockwise Deg. Degree Hz Her
43、tz kN Kilonewton Nm Newton meter RPM Revolutions per Minute 8 Coding System This standard shall be referenced in other documents, drawings, etc., as follows: Test to GMW15930 9 Release and Revisions This standard was originated in May 2008. It was first approved by the Global Fastening and Sealing T
44、est Lab Leadership 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. Moved statement about deviations from Section 1 to Section 4. Revised to allow use of tables simi
45、lar to Appendices B through G. (Fastening & Sealing Test Lab Global Subsystem Leadership Team) 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 STANDAR
46、DS GMW15930 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 7 of 13 Appendix A Figure A1: Schematic for Location of Strain Gages on U-bolt Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking pe
47、rmitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15930 Copyright 2013 General Motors Company All Rights Reserved July 2013 Page 8 of 13 Appendix B Data Sheet B1: Test Required Information Worksheet Project Name: Model Year/Program: Part Number Quantity Description Fastener
48、Diameter Fastener Grade or Class Fastener Pitch 1. Part Disposition at Completion: _. 2. Required Completion Date: _. 3. Master Process Document or Diagram Attached? Y N If Yes, Number _. 4. Tightening Sequence Required, Y 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. Tool Rotati
