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-FM-1.301-GS/PL Former Designation: ESP-FM-1.301-GS TITLE: Tooth Lock Washers Metric Series CURRENT REV No.: 1506 DATE: June 2015 WRITTEN/EDITED BY: Materials Engineering APPROVED BY: Materials Engineering SUPERSEDES: ESP-FM-1.301-GS - August 2006 PRINTED COPIES OF THIS DOCUMEN
3、T 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 safety and health practices and to de
4、termine the applicability of regulatory limits prior to use. Change Notice: Changed to New MPAPS format; Combined GS, GI, PP. 1.0 GENERAL: Implementation of this standard must be in accordance with the policies and procedures outlined in MPAPS S-A-0.101. There may also be supplemental group instruct
5、ions in regard to use of metric standards that should be taken into account. This standard may differ in some respects with certain segments of national standards. In recognition of these differences, the sizes and tolerance ranges used were established in an effort to enable the use of commercially
6、 available items, dimensionally interchangeable worldwide. This specification contains the essentials of the following standards: German Institute Standardization: DIN 6797 It should be noted that the word “Lock“ appearing in the names of the products in this standard is a generic term historically
7、associated with their identification and is not intended to imply an indefinite permanency of fixity in attachments where they are used. The inclusion of dimensional data is not intended to imply that all the washers described are stock production sizes. Inch dimensioned standard washers may be foun
8、d in MPAPS S-F-1.301-GS/PL 2.0 CONTENTS: Page General 1 Design Consideration 2 Assembly Consideration 2 Metric-Inch Related Sizes 2 Color Coding 3 Method of Designation 3 Policy for Selecting Parts for New Design 3 Manufacturing Detail 3 Material and Hardness 3 Finishes 3 Restricted Chemical Substan
9、ces 4 NUMBER: MPAPS S-FM-1.301-GS/PL TITLE: Tooth Lock Washers 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 Navistar, Inc. JUNE
10、 2015 Page 2 of 6 3.0 DESIGN CONSIDERATION: Tooth lock washers providing frictional resistance to loosening, are commonly available in two configurations. Internal Tooth: Used where projection of teeth beyond screw head or nut is objectionable. Presents a finished appearance. External Tooth: Commonl
11、y used in electrical connections and, in general, for applications involving machine screws in sizes smaller than 6 mm. They serve the following functions: 1. Provide a positive electrical ground path through the teeth on painted or coated and irregular mating surfaces. 2. Prevent the electrical ter
12、minal and wire from rotating during installation. 4.0 ASSEMBLY CONSIDERATION: Typical external tooth lock washer applications in electrical connections, depicting placement of the washer, are illustrated below. 5.0 METRIC-INCH RELATED SIZES: During the inch to metric design transition period, the fo
13、llowing chart of related sizes can be used for reference. This information is not to be considered as a recommendation for substitutions but only as a means of determining approximate equivalents. Page Temper Test 4 Clamping Test 4 Twist Test 4 Workmanship 4 Dimensions 5 Part List 5 Technical Inform
14、ation 6 Metric Series mm Approximate Inch Series Metric Series mm Approximate Inch Series 3 #4, #5 12 1/2 4 #6, #8 * 14 9/16 5 #10 16 5/8 6 #12, 1/4 *18 - 8 5/16 20 3/4 10 3/8, 7/16 *Non-Preferred NUMBER: MPAPS S-FM-1.301-GS/PL TITLE: Tooth Lock Washers REVISION: 1506 This document is restricted and
15、 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 3 of 6 6.0 COLOR CODING: Not recommended, except in cases where adequate insurance is needed to pr
16、event mixing of “metric parts“ with look-alike “inch parts.“ The color blue is standard identifier used in some industries. This must be handled internally at individual plants where needed and is meant to be supplemental to the normal finish and easily deleted when the need for supplemental identif
17、ication no longer exists. The supplemental blue color should not be used on finishes such as chromium bright which are specified for cosmetic purposes or phosphate coating which may cause a loss of color identity. The supplemental blue color may be detrimental for electrical applications. 7.0 METHOD
18、 OF DESIGNATION: Washers will be designated on purchase orders by nominal size, word description, finish, and part number as shown in the following examples: 5 mm, External Tooth Lock Washer, PHC, Part Number 6 mm, Internal Tooth Lock Washer, ZN6A, Part Number 8.0 POLICY FOR SELECTING PARTS FOR NEW
19、DESIGN: Approved parts are so designated to reduce variety of parts and assure maximum availability, interchangeability and cost savings. For new design, parts shall be selected from “Approved“ part list only. Nominal Sizes: All sizes shown except 14 and 18 mm Material & Finish: Carbon steel, Zinc T
20、rivalent (ZN6A) 9.0 MANUFACTURING DETAIL: The number of teeth, the length of the teeth, the width of the rim and the thickness of the washer over the teeth (free height) will be optional with the manufacturer, with the provision, however, that the projection of the teeth on both sides of the washer
21、will be uniform within a tolerance equal to one half of the projection on one side. 10.0 MATERIAL AND HARDNESS: Washers will be carbon steel or stainless steel conforming to the specifications below: Carbon steel washers will be fabricated and heat treated to a hardness of Rockwell C 40-50, or equiv
22、alent. Stainless steel washers will be fabricated from AISI 410 per MPAPS A-37 or equivalent and heat treated to a hardness of Rockwell C 40-50, or equivalent. It is recommended that the lighter, more sensitive depth reading, Rockwell A scale or equivalent be used for testing hardness of washers hav
23、ing thin section. Decarburization will be removed before checking hardness. 11.0 FINISHES: Washers will be furnished plain or plated in accordance with the International Engineering Material Specification and class listed below: Zinc Trivalent (ZN6A) MPAPS G-20, Class 6A. Phosphate Coated (PHC) MPAP
24、S G-1, Class B-2. (Not recommended for electrical applications.) It should be noted that chromium and nickel plating on carbon steel tooth lock washers is generally unsatisfactory. Therefore, the use of these finishes will not be considered for this standard. The determinant of plating thickness wil
25、l be the thickness of plating or coating on the flat surface of the rim of the washers, approximately midway across the width of rim. NUMBER: MPAPS S-FM-1.301-GS/PL TITLE: Tooth Lock Washers REVISION: 1506 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without p
26、ermission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2015 by Navistar, Inc. JUNE 2015 Page 4 of 6 Carbon steel washers plated with metal or otherwise processed as to be subject to hydrogen embrittlement will be suitably treated, subsequent to plating o
27、r coating operation, to obviate such embrittlement and will be subjected to a clamping test. 12.0 RESTRICTED CHEMICAL SUBSTANCES: Effective January 1, 2007, all product supplied to the requirements of this specification must comply with the requirements of the MPAPS B-50 specification. 13.0 TEMPER T
28、EST: Washers after being compressed to a height equal to the actual material thickness plus 0.13 mm, then released, will have a free height greater than the compressed height. Compression will be accomplished between parallel flat surfaces for flat varieties of tooth washers. 14.0 CLAMPING TEST: Pla
29、ted washers will be clamped to a height equal to the actual material thickness plus 0.13 mm for a period of 24 hours without breaking. The clamping will be accomplished between parallel flat surfaces for flat varieties of tooth washers. 15.0 TWIST TEST: The rim of the lock washer will be cut or seve
30、red with a cold chisel or cutting pliers and the severed ends will be gripped by pliers or vise and pliers (Fig. 1). Separation of the ends in the form of a helix, to a distance equal to the inside diameter of the washer, will not result in fracture. When the ends are separated a greater distance an
31、d the washer does fracture, the structure at the point of fracture will show a fine grain, and the washer up to the instant of fracture will deliver a tough springy reaction. 16.0 WORKMANSHIP: Washers will be symmetrical in shape and free from rust, loose scale and defects that might affect their se
32、rviceability. NUMBER: MPAPS S-FM-1.301-GS/PL TITLE: Tooth Lock Washers 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 Navistar, I
33、nc. JUNE 2015 Page 5 of 6 17.0 DIMENSIONS: Dimensions in millimeters: Nominal Size* A B C Inside Outside Thickness Diameter Diameter Max Min Max Min Max Min 3 3.38 3.15 7.35 5.7 0.5 0.35 4 4.48 4.15 8.75 7.64 0.6 0.45 5 5.52 5.15 10.5 9.64 0.7 0.55 6 6.62 6.4 11 10.57 0.75 0.55 8 8.62 8.2 15.5 14.57
34、 0.85 0.7 10 10.77 10.2 18 16.85 1 0.8 12 12.77 12.3 20.5 19.5 1 0.8 *14 14.8 14.3 24 22 1.15 0.94 16 17 16.4 27.2 25.48 1.27 1.05 *18 19.33 19 30 29.48 1.48 1.2 20 21.33 20.5 33 31 1.48 1.2 * Non-Preferred * Nominal washer sizes are intended for use with comparable nominal screw, bolt, or nut sizes
35、. 18.0 PART LIST: 18.1 Approved: Nominal Size Washer Type Min Inside Diameter Min Outside Diameter Finish Part Number 4 EXT 4.15 7.64 ZN6A 934946R1 4 INT 4.48 7.64 ZN6A 40330R1 6 EXT 6.4 10.57 ZN6A 30480R1 10 EXT 10.2 16.85 ZN6A 934494R1 NUMBER: MPAPS S-FM-1.301-GS/PL TITLE: Tooth Lock Washers REVIS
36、ION: 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 Navistar, Inc. JUNE 2015 Page 6 of 6 19.0 TECHNICAL INFORMATION: For further informatio
37、n 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:/
