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. JUNE 2008 Page 1 of 2 NAVISTAR, INC. Engineering Standard Parts NUMBER: ESP-E-72.1
2、01-GS TITLE: Crown Nuts General Specifications (Noun Code 5780) CURRENT ISSUE DATE: June 2008 WRITTEN/REVIEWED BY: Corporate Technical Standards APPROVED BY: Corporate Technical StandardsSUPERSEDES ISSUE OF: August 2006PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CURRENT REVISION Change Noti
3、ce: Added Black Zinc (BLZ) finish specification. Replaced International Truck and Engine Corporation with Navistar, Inc. per corporate directive. MISCELLANEOUS DIMENSIONS: The bearing surface of nuts will be flat with chamfered corners, the diameter of bearing circle being the maximum width across f
4、lats within a tolerance of minus 5 percent. Tops of hexagons will be chamfered from the boss diameter. The length of chamfers at hexagon corners will be from .05 to .15 times the basic thread diameter. The surface of chamfers may be slightly convex or rounded. A rounding or lack of fill at junction
5、of corners with chamfer will be permissible provided the minimum width across corners is reached and maintained beyond a distance of .175 times the basic thread diameter from both the bearing face and the top of hexagon portion of nut. The bearing surface will be at right angles to the axis of the t
6、hreaded hole within 2 for 5/8 inch size, or smaller; and within 1 for larger sizes. (The maximum total runout of bearing face equals the tangent of the specified angle times the width across flats.) Actual size across flats will be not less than specified minimum limit between two planes, perpendicu
7、lar to the axis of the nut, spaced at a distance equal to .25 times hexagon thickness above and below the mid-plane through the nut flats. Tolerance on dimensions not otherwise controlled will be plus and minus .010 inch. The threaded hole will be at true position within a tolerance zone having a ra
8、dius equal to .03 times the maximum width across flats, regardless of feature size, and will be countersunk on the bearing face. The maximum countersink diameter will be the thread basic diameter plus .025 inch for 3/8 inch size, or smaller; and plus .06 times the basic thread diameter for larger si
9、zes. The minimum countersink diameter and depth will be such that no part of the threaded portion projects beyond the bearing face. THREADS: Threads will be Unified Coarse or Fine (UNC, UNF) Class 2B. MATERIAL: Steel (STL), Type 5, per CEMS A-31, Part II. Stainless steel (SST-304) Type 304 per CEMS
10、A-37. Brass (BRS) C36000 or equivalent, hard temper, per CEMS C-3. Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-E-72.101-GS TITLE: Crown Nuts General Specifications
11、 CURRENT ISSUE DATE: June 2008 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. JUNE 2008 Page 2 of 2 Minimum Proof Load, psi Nomin
12、al Low Crown Nuts High Crown Nuts Size Range Coarse Thread Fine Thread Coarse Thread Fine Thread 1/4 to 3/4, incl 7/8 and 1 1-1/8 and 1-1/4 132,000126,000115,500120,000115,000105,000141,000 135,000 123,000 128,000 122,500 112,000 FINISHES: Nuts will be furnished plain, plated or coated in accordance
13、 with CEMS and class listed below: Zinc Trivalent (ZN6A) on steel CEMS G-20, Class 6A. Chromium Bright (CRB) on steel CEMS G-19, Part III, Class 3, 5, or 8 depending on pitch. Chromium Bright (CRB) on brass CEMS G-19, Part III, Class 3, 5, or 8 depending on pitch. Black Zinc (BLZ) on steel TMS-4113
14、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. SURFACE DISCONTINUITIES: Will conform to allowable limits shown in SAE Recommended Practice J122, “Sampling Procedure“ and “Methods of Test“ per CEMS A-31, Part II. Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
