1、This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2015 by Navistar, Inc. JUNE 2015 Page 1 of 6 NAVISTAR, INC. Material, Parts, and Process Specifications (
2、MPAPS) NUMBER: MPAPS S-B-4.101-GS/PL Former Designation: ESP-B-4.101-GS TITLE: Prevailing-Torque Hexagon Head Bolts - English Series (Noun Code 0810) CURRENT REV No.: 1506 DATE: June 2015 WRITTEN/EDITED BY: Materials Engineering APPROVED BY: Materials Engineering SUPERSEDES: ESP-B-4.101-GS - Decembe
3、r 2012 PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CURRENT REVISION This specification may involve hazardous materials, equipment, and procedures. This specification does not purport to address all of the safety issues associated with its use. The user is responsible to consult appropriate
4、safety and health practices and to determine the applicability of regulatory limits prior to use. Change Notice: Changed to New MPAPS format; Combined GS, PP, NPP. 1.0 GENERAL: A prevailing-torque bolt is one which is torsionally resistant to rotation due to a self-contained prevailing- torque featu
5、re and not because of a compressive load developed against the under head bearing surface, a tensile load developed in the shank, or frictional devices designed into the underside of the head. These latter types normally are considered “free running“ locking bolts and have high breakaway torsion req
6、uirements but no prevailing-torque. A prevailing-torque bolt intends to delay or prevent total disassembly of joint when clamp force is decreased or ceases to exist. The threaded fasteners covered by this standard are prevailing-torque hexagon head bolts with a non-metallic plastic patch bonded to a
7、 specified portion of the threads to provide the prevailing-torque feature. These bolts are for applications where temperatures will not exceed 250 F. All mating tapped holes should be countersunk before threading. Included angle of countersinks should be 90 degrees and the diameter of countersinks
8、should be .030 inch larger than the nominal diameter of the thread for 1/4 inch size up to .040 inch to .050 inch over nominal for larger sizes. 2.0 RESTRICTED CHEMICAL SUBSTANCES: Effective January 1, 2007, all product supplied to the requirements of this specification must comply with the requirem
9、ents of the MPAPS B-50 specification. NUMBER: MPAPS S-B-4.101-GS/PL TITLE: Prevailing-Torque Hexagon Head Bolts REVISION: 1506 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume
10、all patent liability. 2015 by Navistar, Inc. JUNE 2015 Page 2 of 6 3.0 CONTENTS: Page General 1 Restricted Chemical Substances 2 Basic Bolt 2 Surface Discontinuities 2 Policy for Selecting Parts for New Design 2 Prevailing-Torque Feature 2 Prevailing-Torque Performance Requirements 2 Test Method 3 P
11、art List 5 Technical Information 6 4.0 BASIC BOLT: The bolt must comply in all respects with the General Specification for Hexagon Head Bolts, MPAPS S-B-1.101-GS/PL. 5.0 SURFACE DISCONTINUITIES: Per MPAPS F-31. The use of serrated thread rolling dies is optional for the parts contained in and refere
12、nced to this standard. 6.0 POLICY FOR SELECTING PARTS FOR NEW DESIGN: For new design, parts shall be selected from “Approved“ part list only. Material: Type 8 Finish: Phosphate Coating (PHC) Diameters: 1/4, 5/16, 3/8, 1/2, 5/8, 3/4, 1, 1-1/4, 1-1/2 inches Threads: Unified Coarse (UNC) Length Increme
13、ntation: Same as Hexagon Head Bolts 7.0 PREVAILING-TORQUE FEATURE: The location and size of the non-metallic plastic patch must comply with the illustration shown above. Bolts will assemble a minimum of one full turn by hand into any mating internally threaded component that is accepted by a properl
14、y selected GO thread plug gage. The prevailing-torque feature will be free from visible porosity, voids, and cracks, and will be uniform in color without streaks, dark areas or other indicators of contamination or degradation. It will be firmly attached to the bolt and will not loosen under normal h
15、andling. It will be chemically inert to Regular Gear Lubricant Grade 90 HR, Navistar CEMS B-22; Heavy Duty Type Engine Oil Grade 10W-30HD, Navistar MPAPS B-21, Part II; Anti-freeze, Single Phase, Ethylene Glycol Base, Navistar MPAPS B-1; and “Hy-Tran Fluid,“ Navistar CEMS B-6. 8.0 PREVAILING-TORQUE
16、PERFORMANCE REQUIREMENTS: The prevailing torque of lock bolts occurring during any installation or removal will not exceed the maximum prevailing torque specified in Table 1 when tested as specified on page 3. In addition, the maximum prevailing torques developed by lock screws during first and fift
17、h removals will not be less than the minimum removal torques specified in Table 1 when tested in accordance with method described below Table 1. NUMBER: MPAPS S-B-4.101-GS/PL TITLE: Prevailing-Torque Hexagon Head Bolts REVISION: 1506 This document is restricted and may not be sent outside Navistar,
18、Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2015 by Navistar, Inc. JUNE 2015 Page 3 of 6 TABLE I Nominal Bolt Diameter PREVAILING-TORQUES First Installation Maximum First Removal Minimum Fifth Removal Minimum inch i
19、n lb ft lb in lb in lb 1/4 40 3.3 5.0 3.0 5/16 85 7.1 8.0 5.0 3/8 110 9.2 14 9.0 7/16 150 12.5 20 12 1/2 220 18.3 26 16 9/16 270 22.5 35 22 5/8 350 29.2 45 30 3/4 460 38.3 60 45 7/8 700 58.3 95 65 1 900 75 130 85 1-1/8 1050 87.5 150 110 1-1/4 1150 95.8 200 140 1-3/8 1300 108.3 240 150 1-1/2 1500 125
20、 280 185 9.0 TEST METHOD: Test Nut: The test nut will be a heavy nut conforming to ANSI B18.2.2; phosphate coated per MPAPS G-1, Class B-2; Class 2B thread; carbon steel with hardness as specified below: A new test nut will be used for each bolt tested. Test Washer: The washer will conform to the di
21、mensional, metallurgical and mechanical requirements given in Table 2. A new washer will be used for each bolt tested. Minimum Specified Ultimate Tensile Strength of Bolt Being Tested Nominal Size of Test Nut Rockwell Hardness To and Including 120,000 psi 1/4 thru 1-1/2 in 85/100 HRB Over 120,000 ps
22、i To and Including 150,0000 psi 1/4 thru 5/8 in 24/32 HRC Over 5/8 in thru 1 in 26/34 HRC Over 1 in thru 1-1/2 in 26/36 HRC NUMBER: MPAPS S-B-4.101-GS/PL TITLE: Prevailing-Torque Hexagon Head Bolts REVISION: 1506 This document is restricted and may not be sent outside Navistar, Inc. or reproduced wi
23、thout permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2015 by Navistar, Inc. JUNE 2015 Page 4 of 6 Material will be carbon steel with a chemical composition of C .48 to .60%, Mn .60 to 1.50%, P .035% max, and S .045% max, quenched and tempered, w
24、ith a surface hardness of Rockwell 15N 85 to 88, and a core hardness (midway between faces) of Rockwell A73 to 78. Washers will be Zinc Trivalent, Class 6A (ZN6A) per MPAPS G-20, Class 6A. Tensile Load Measuring Device: The tensile load measuring device will be an instrument capable of measuring the
25、 actual tension induced in the test bolt as it is being tightened. The device will be accurate within 1-1/2 percent of the tensile clamp load to be induced. Diameter of the test bolt clearance hole in the backing plate will be the test bolt nominal diameter plus .031 in. Torque Wrenches: Wrenches wi
26、ll be accurate within 2 percent of the maximum of the specified torque range of the wrench. Prevailing -Torque Procedure: 1. A test washer and spacer will be placed on the sample bolt, the bolt inserted in a tensile load measuring device and a test nut assembled on the bolt. During the complete perf
27、ormance of the test, the bolt will be turned and the test washer, spacer and test nut will be restrained from turning. The restraining mechanism will be such that it imparts no radial distortion to the test nut during assembly. 2. The bolt will be advanced until its under head bearing surface is sea
28、ted against the test washer. The total thickness of spacer material in the test assembly will be selected so that at bolt seating the prevailing-torque feature will be fully engaged within the test nut, and a minimum length of bolt equivalent to two thread pitches will project through the test nut.
29、During this first installation, the maximum torque (including breakthrough) occurring while the bolt is in motion prior to development of any axial load will be known and recorded as first installation prevailing-torque. TABLE 2 Dimensions in inches: Nominal Bolt Dia. Inside Dia. Width Thickness C (
30、in) (in) A (in) B (in) Max Min 1/4 .281 .656 .080 .073 5/16 .344 .776 .080 .073 3/8 .406 .892 .080 .073 7/16 .469 1.018 .080 .073 1/2 .531 1.152 .121 .114 9/16 .625 1.274 .121 .114 5/8 .688 1.422 .121 .114 3/4 .812 1.678 .160 .153 7/8 .969 1.916 .160 .153 1 1.125 2.184 .160 .153 1-1/8 1.250 2.318 .1
31、92 .185 1-1/4 1.375 2.562 .192 .185 1-3/8 1.500 2.804 .213 .206 1-1/2 1.625 3.046 .213 .206 NUMBER: MPAPS S-B-4.101-GS/PL TITLE: Prevailing-Torque Hexagon Head Bolts REVISION: 1506 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate
32、Technical Standards. Suppliers are required to assume all patent liability. 2015 by Navistar, Inc. JUNE 2015 Page 5 of 6 3. Tightening will be continued until an axial tensile load equal to 75 percent of specified proof load for the test bolt is developed. The axial tensile load in the bolt will be
33、reduced to zero by backing off the bolt. The highest and lowest torques occurring while the bolt is being backed off throughout the next 360 degrees rotation will be known and recorded as prevailing off, first removal, torque. The bolt will then be backed off until the prevailing-torque feature is d
34、isengaged from the nut thread. The sample bolt will be reassembled and removed four more times. On each reassembly, the bolt will be assembled only to the initial first off position, with no clamp load induced in the bolt. During each of these four additional test cycles, the highest values of preva
35、iling installation and highest and lowest off torque will be recorded as second thru fifth installation and removal prevailing-torque. Sufficient time will elapse between torquing cycles to prevent overheating (warm to the touch) of the test assembly. Driving speed will not exceed 30 rpm. 10.0 PART
36、LIST: 10.1 Approved: Nominal Size-TPI Length Finish Material Part Number 1/4 -20 3/4 PHC 8 26674R1 1/4-20 1-1/4 PHC 8 27353R1 1/4 -20 1-1/2 PHC 8 26676R1 5/16 -18 1-1/2 PHC 8 26680R1 5/16 -18 2 PHC 8 27430R1 5/16 -18 2-1/4 PHC 8 40041R1 5/16 -18 3-1/4 PHC 8 26681R1 5/16 -18 3-3/4 PHC 8 28565R1 3/8 -
37、16 1/2 PHC 8 27431R1 3/8 -16 1-3/4 PHC 8 26499R1 3/8 -16 2 PHC 8 27035R1 3/8 -16 2-1/2 PHC 8 27281R1 3/8 -16 2-3/4 PHC 8 26325R1 3/8 -16 4 PHC 8 27605R1 1/2 -13 2-3/4 PHC 8 27408R1 1/2 -13 3 PHC 8 27409R1 5/8 -11 2-1/4 PHC 8 27434R1 5/8 -11 2- 3/4 PHC 8 27436R1 5/8 -11 4 PHC 8 26574R1 3/4 -10 2-1/4
38、PHC 8 27437R1 Nominal Size-TPI Length Finish Material Part Number 3/4 -10 2-1/2 PHC 8 27840R1 3/4 -10 4 PHC 8 27979R1 1/4-20 5/8 PHC 8 27565R1 1/4-20 1-1/8 PHC 8 27020R1 5/16-18 1-1/8 PHC 8 27971R1 5/16-18 1-3/8 PHC 8 27735R1 5/16-18 1-5/8 PHC 8 28338R1 5/16-18 2-1/4 ZN8F 5 217288R1 3/8-16 1-1/8 PHC
39、 8 27347R1 7/16-14 1-1/8 PHC 8 28138R1 7/16-14 1-1/4 PHC 8 26315R1 7/16-14 1-5/8 PHC 8 27410R1 1/2-13 1-5/8 PHC 8 27412R1 1/2-20 1-1/4 PHC 8 27964R1 9/16-12 1 PHC 8 26473R1 9/16-12 2 PHC 8 40001R1 9/16-12 2-1/2 PHC 8 40033R1 9/16-18 1-3/4 PHC 8 40424R1 9/16-18 2-1/2 PHC 8 40425R1 9/16-18 2-3/4 PHC 8
40、 40426R1 NUMBER: MPAPS S-B-4.101-GS/PL TITLE: Prevailing-Torque Hexagon Head Bolts REVISION: 1506 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2015 by
41、 Navistar, Inc. JUNE 2015 Page 6 of 6 10.2 Not for New Design: Nominal Size-TPI Length Finish Material Part Number 1/4 -20 1/2 PHC 8 26673R1 1/4 -20 1 PHC 8 26675R1 5/1 -18 1/2 PHC 8 27245R1 5/16 -18 3/4 PHC 8 26677R1 5/16 -18 1 PHC 8 26678R1 5/16 -18 1-1/4 PHC 8 26679R1 5/16 -18 1-3/4 PHC 8 27439R1
42、 3/8 -16 3/4 PHC 8 26309R1 3/8 -16 1 PHC 8 26310R1 3/8 -16 1-1/4 PHC 8 26311R1 3/8 -16 1-1/2 PHC 8 26312R1 1/2 -13 1 PHC 8 26316R1 1/2 -13 1-1/4 PHC 8 26317R1 1/2 -13 1-1/2 PHC 8 26318R1 1/2 -13 2-1/4 PHC 8 26319R1 5/8 -11 1 PHC 8 26957R1 5/8 -11 1-1/4 PHC 8 26321R1 Nominal Size-TPI Length Finish Ma
43、terial Part Number 5/8 -11 1-3/4 PHC 8 26475R1 5/8 -11 2 PHC 8 26322R1 5/8 -11 1-1/2 PHC 8 26510R1 5/8 -11 2-1/2 PHC 8 27435R1 5/8 -11 3 PHC 8 28241R1 5/8 -11 3-1/2 PHC 8 28267R1 3/4 -10 1-1/2 PHC 8 26323R1 3/4 -10 2 PHC 8 27356R1 3/8-16 7/8 PHC 8 27768R1 3/8-16 1-5/8 PHC 8 27348R1 7/16-14 1-1/2 PHC
44、 8 26974R1 7/16-14 1-3/4 PHC 8 27438R1 7/16-14 2 PHC 8 27411R1 7/16-20 7/8 ZN8F 8 40288R1 7/16-20 1-1/4 PHC 8 27261R1 7/16-20 1-1/2 ZN8F 8 40376R1 11.0 TECHNICAL INFORMATION: For further information related to the technical content of this specification, contact: Suppliers may purchase controlled copies of this specification by contacting: Materials Engineering and Technology Dept. 10400 W. North Avenue Melrose Park, IL 60160 E-mail: MaterialsEngineeringN IHS Global Inc. 15 Inverness Way East Englewood CO 80112-5776 Phone: 1-800-854-7179 E-mail: AutomotiveIHS.com Website: http:/
