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. 2008 by Navistar, Inc. MAY 2008 Page 1 of 7 NAVISTAR, INC. Engineering Standard Parts NUMBER: ESP-E-56.10
2、1-GS TITLE: Prevailing Torque Hex Locknuts All Metal - General Specifications (Noun Code 5780) CURRENT ISSUE DATE: May 2008 WRITTEN/REVIEWED BY: Corporate Technical Standards APPROVED BY: Corporate Technical StandardsSUPERSEDES ISSUE OF: August 2006PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FO
3、R CURRENT REVISION Change Notice: Eliminated Zinc Trivalent plus Sealer (ZN8F) finish. Replaced International Truck and Engine Corporation with Navistar, Inc. per corporate directive. GENERAL: Prevailing torque type locknuts, as defined for this standard, are all metal, one piece locknuts which spin
4、 on freely until the locking element engages the mating part. These nuts must be wrenched to final position. They will lock in any position on a bolt providing the locking element is fully engaged by the bolt threads. Prevailing torque locknuts do not depend on the bolt being loaded for locking acti
5、on. The locking feature will consist of three constrictions equally spaced or two constrictions diametrically opposed. The constrictions usually appear on the top of the conical surface, though two constrictions on the upper portion of the flats diametrically opposite are permissible. MATERIAL: Thes
6、e nuts are available in three strength grades, International Types 1, 5, and 8, approximate IFI Grades A, B and C) per CEMS A-31, Part II. (Type 8 nuts with a hardness in excess of Rockwell C32 plated with metal must be suitably treated to relieve hydrogen embrittlement. For convenience, proof load
7、requirements are shown in the Proof Load, Clamp Load Table in the document. MARKING: Type 1 locknuts are not required to be marked for grade identification. Type 5 - three equally or symmetrically spaced, raised projections must appear on top of the conical urface for grade identification. sType 8 -
8、 Six equally or symmetrically spaced, raised projections must appear on top of the conical urface for grade identification. sDouble projections at one or more locations, radial or circumferential linear marks or letters in locking constrictions or corners may be used for source identification. THREA
9、D START: Constriction of the locking feature will be such that nuts 3/8 inch size and smaller will assemble a minimum of one half turn, and size 7/16 inch and larger a minimum of one full turn, by hand, on a basic “GO“ thread plug gage. The plug gage will be without a chip groove, and will have a po
10、int with dimensions conforming to those for the point on hex capscrews as specified in International Engineering Standard Parts Book, Section B. BASIC DIMENSIONS: Prevailing torque locknuts will conform to the dimensions given in the Dimensions Table in this document. The portion of the locknut cont
11、aining the prevailing torque feature Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-E-56.101-GS TITLE: Prevailing Torque Hex Lockout All Metal CURRENT ISSUE DATE: May
12、 2008 General Specifications This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate may have a special contour within the maximum permitted width across flats and thickness. The minimum width across flats will not apply at depressed por
13、tion of locknut at prevailing torque feature. BEARING SURFACE: Bearing surface will be flat with chamfered corners and square with axis of threaded hole pitch cylinder such that total runout over bearing circle is within “Bearing Surface TIR“ shown in the Dimensions Table in this document. HOLE CONC
14、ENTRICITY: The axis of pitch cylinder of threaded hole will be concentric with axis of nut within TIR specified in the Dimensions Table in this document (3% maximum width across flats). COUNTERSINK ON BEARING SURFACE: The threaded hole will be countersunk on the bearing surface. The diameter of coun
15、tersink will not exceed the thread basic (major) diameter plus .030 inch for sizes 3/8 inch and smaller of 1.08 times the thread basic diameter for larger sizes. FINISHES: Nuts will be furnished plated or coated in accordance with the specification below. Phosphate Coating (PHC) CEMS G-1, Class B2.
16、Zinc Aluminum Clear (ZACLR) TMS-4518, Type II. RESTRICTED CHEMICAL SUBSTANCES: Effective January 1, 2007, all product supplied to the requirements of this specification must comply with the requirements of the CEMS B-50 specification. LUBRICATION: To minimize galling during assembly and promote unif
17、orm performance, cadmium plated nuts will be coated with a supplemental lubricant following plating which will be clean and dry to the touch. Lubricant will not deteriorate due to temperature and humidity variations so as to affect nut performance for a period of one year when nuts are stored, shipp
18、ed, or handled in a normal manner. TEST CONDITIONS: Prevailing Torque and Torque Tension Test Section Through Typical Test Machine (Hydraulic Load Cell) The same grade steel bolt and nut should be used for testing (Type 5 bolt with Type 5 nut). The test bolt used in the prevailing torque test will h
19、ave a zinc phosphate and oil finish without any additional lubrication such as oil, grease, or wax which would alter frictional characteristics of threads. Bolt threads will be Unified Series Class 2A rolled, on sizes 1 inch diameter and smaller. Test washers will be non-rotating (square washers are
20、 recommended), hardened, with electrodeposited zinc plating. Technical Standards. Suppliers are required to assume all patent liability. 2008 by Navistar, Inc. MAY 2008 Page 2 of 7 Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or
21、networking permitted without license from IHS-,-,-NUMBER: ESP-E-56.101-GS TITLE: Prevailing Torque Hex Lockout All Metal CURRENT ISSUE DATE: May 2008 General Specifications A new test bolt and test washer will be used for testing each nut. TESTING: All torque specifications tabulated in the Proof Lo
22、ad and Prevailing “on” and “off” torque tables apply only to locknuts having the required plating, lubrication, and assembled as illustrated under test conditions. A hand torque wrench or mechanical drive unit will be used for all assembly and bly operations. Driving speed must not exceed 30 rpm and
23、 will be continuous and uniform. disassemOn initial assembly, the maximum prevailing torque “on“ will be recorded and will not exceed the prevailing torque first time on, specified in the Prevailing “on” and “off” torque table. The nut will be tightened against the hardened washer until the specifie
24、d clamping load is developed in the bolt. The torque necessary to develop this load will be recorded and must be within the specified limits for tightening torque. The nut will then be backed off until the tensile load in the bolt has been reduced to zero or an axial play of .031 inch maximum is obt
25、ained. There must be perceptible drag or torque encountered throughout the next 360 degrees of rotation and the maximum and minimum torque obtained will be recorded. The maximum torque will not be less than the first removal “highest reading“ prevailing torque “off“ (as specified on in the Prevailin
26、g “on” and “off” torque table) and in addition, will not be less than 40% of the actual prevailing torque “on“ during first installation. The nut will be reassembled and removed four more times. On each reassembly, the nut will be assembled to approximately the initial loaded position without induci
27、ng any clamp load in the bolt. This portion of the test need not be conducted in the load cell, however, where the load cell is used, the test washer will be removed. Regardless of the method used, caution must be exercised to avoid engaging the locking element of the nut with bolt threads not previ
28、ously contacted. The maximum and minimum prevailing torque “off“ will be measured on each assembly and removal. During the fifth removal, there must be perceptible torque throughout the first 360 degrees of rotation and the maximum and minimum torque will be recorded. This torque must not be less th
29、an the specified prevailing torque “off“, fifth time off. Sufficient time will elapse between torquing cycles to prevent over heating of the test assembly. Prevailing Torque “Off“ will be measured on each assembly and removal and will conform with the typical curve illustrated below. Applications Ty
30、pical Curve of Prevailing Torque on Removal versus Times Applied Note: 1st off through 5th off may be constant or diminishing after each subsequent application. If the test bolt is free of total decarburization and the above curve has a pronounced upswing, thread galling is indicated and nut will be
31、 subject to rejection. 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. 2008 by Navistar, Inc. MAY 2008 Page 3 of 7 Copyright Navistar International Corpo
32、ration Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-E-56.101-GS TITLE: Prevailing Torque Hex Lockout All Metal CURRENT ISSUE DATE: May 2008 General Specifications This document is restricted and may not be sen
33、t outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2008 by Navistar, Inc. MAY 2008 Page 4 of 7 PREFERRED PARTS POLICY: Preferred parts are so designated to reduce variety of parts and assure maximum ava
34、ilability, interchangeability and cost savings in volume buying. Material: Types 5 and 8 Thread: Unified Series, Coarse Finishes: Zinc Aluminum Clear (ZACLR) Phosphate Coated (PHC) Sizes: 1/4, 5/16, 3/8, 1/2, 5/8, 3/4, 1, 1-1/4, and 1-1/2 SURFACE DISCONTINUITIES: Steel nuts in all sizes will conform
35、 to allowable limits shown in SAE Recommended Practice J122. Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-E-56.101-GS TITLE: Prevailing Torque Hex Lockout All Metal
36、 CURRENT ISSUE DATE: May 2008 General Specifications This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Dimensions in inches: C E D D Identi- fica- tion Mark Width Across Corners Thickness Types 1 & 8 Thickness Type 5 Height of Hex
37、Diameter of Bearing Surface Angula- rity of Bearing Surface TIR Hole Concen- tricity TIR Identi- fica- tion Mark Dia Height Nominal Size Threads Per Inch Nom Max Min Max Min Max Min Max Min Min Max Min Max Max Min Min 1/4 20 7/16 .4375 .428 .505 .488 .226 .212 .257 .212 .145 .438 .416 .010 .015 .010
38、 .004 *1/4 28 7/16 .4375 .428 .505 .488 .226 .212 .257 .212 .145 .438 .416 .010 .015 .010 .004 5/16 18 1/2 .5000 .489 .577 .557 .273 .258 .302 .258 .166 .502 .475 .011 .017 .012 .005 *5/16 24 1/2 .5000 .489 .577 .557 .273 .258 .302 .258 .166 .502 .475 .011 .017 .012 .005 3/8 16 9/16 .5625 .551 .650
39、.628 .337 .320 .377 .320 .198 .564 .534 .012 .020 .015 .006 *3/8 24 9/16 .5625 .551 .650 .628 .337 .320 .377 .320 .198 .564 .534 .012 .020 .015 .006 *7/16 14 11/16 .6875 .675 .794 .768 .385 .365 .430 .365 .223 .689 .653 .013 .024 .017 .007 *7/16 20 11/16 .6875 .675 .794 .768 .385 .365 .430 .365 .223
40、 .689 .653 .013 .024 .017 .007 1/2 13 3/4 .7500 .736 .866 .840 .448 .427 .510 .427 .262 .752 .712 .014 .026 .020 .008 *1/2 20 3/4 .7500 .736 .866 .840 .448 .427 .510 .427 .262 .752 .712 .014 .026 .020 .008 *9/16 12 7/8 .8750 .861 1.010 .982 .496 .473 .555 .473 .286 .877 .830 .015 .030 .022 .009 *9/1
41、6 18 7/8 .8750 .861 1.010 .982 .496 .473 .555 .473 .286 .877 .830 .015 .030 .022 .009 5/8 11 15/16 .9375 .922 1.083 1.051 .559 .535 .645 .535 .329 .939 .890 .016 .032 .025 .010 *5/8 18 15/16 .9375 .922 1.083 1.051 .559 .535 .645 .535 .329 .939 .890 .016 .032 .025 .010 3/4 10 1- 1/8 1.1250 1.088 1.29
42、9 1.240 .665 .617 .750 .617 .382 1.127 1.069 .018 .039 .030 .012 *3/4 16 1- 1/8 1.1250 1.088 1.299 1.240 .665 .617 .750 .617 .382 1.127 1.069 .018 .039 .030 .012 *7/8 9 1- 5/16 1.3125 1.269 1.516 1.447 .776 .724 .862 .724 .450 1.314 1.246 .020 .045 .030 .012 *7/8 14 1- 5/16 1.3125 1.269 1.516 1.447
43、.776 .724 .862 .724 .450 1.314 1.246 .020 .045 .030 .012 1 8 1- 1/2 1.5000 1.450 1.732 1.653 .887 .831 .958 .831 .513 1.502 1.425 .022 .052 .030 .012 1 14 1- 1/2 1.5000 1.450 1.732 1.653 .887 .831 .958 .831 .513 1.502 1.425 .022 .052 .030 .012 *1-1/8 7 1-11/16 1.6875 1.631 1.949 1.859 .999 .939 1.07
44、9 .939 .576 1.689 1.603 .025 *1-1/8 12 1-11/16 1.6875 1.631 1.949 1.859 .999 .939 1.079 .939 .576 1.689 1.603 .025 1-1/4 7 1- 7/8 1.8750 1.812 2.165 2.066 1.094 1.030 1.175 1.030 .628 1.877 1.781 .028 *1-1/4 12 1- 7/8 1.8750 1.812 2.165 2.066 1.094 1.030 1.175 1.030 .628 1.877 1.781 .028 1-1/2 6 2-
45、1/4 2.2500 2.175 2.598 2.480 1.317 1.245 1.517 1.245 .757 2.252 2.138 .034 *1-1/2 12 2- 1/4 2.2500 2.175 2.598 2.480 1.317 1.245 1.517 1.245 .757 2.252 2.138 .034 * NON-PREFERRED * NOT RECOMMENDED See ESP-E-56.121-PP for part numbers Technical Standards. Suppliers are required to assume all patent l
46、iability. 2008 by Navistar, Inc. MAY 2008 Page 5 of 7 Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-E-56.101-GS TITLE: Prevailing Torque Hex Lockout All Metal CURREN
47、T ISSUE DATE: May 2008 General Specifications 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. 2008 by Navistar, Inc. MAY 2008 Page 6 of 7 PROOF LOAD, CLA
48、MP LOAD, TIGHTENING TORQUE Type 1 Type 5 Type 8 Type 5 Type 8 Nominal Locknut Locknut Size & Proof *Clamp Proof *ClampProof *Clamp Tightening Torque Tightening Torque Threads Load Load Load Load Load Load Per Inch lb lb lb lb lb lb Max Min Max Min 1 /4 -20 2, 850 1,300 3,800 2,000 4,750 2,850 84 lb in 60 lb in 126 lb in 84 lb in 1/4 -28 3,300 1,500 4,350 2,300 5,450 3,250 87 lb in 63 lb in 126 lb in 84 lb in 5/16 -18 4,700 2,150 6,300 3,350 7,850 4,700 162 lb in
