1、 WORLDWIDE FASTENER STANDARDWE901 Date: 2004-09-01 Printed copies are uncontrolled Copyright 2004, Ford Global Technologies, LLC. Page 1 of 1 WE 901 General Requirements for Nut and Washer Assemblies 1. SCOPE. This standard specifies the dimensional and performance requirements for nut and washer as
2、semblies for general use. 2. REFERENCES. WE 900 - Dimensional requirements for prevailing torque type steel metric hex nuts and hex flanged nuts. WE 910 - Dimensional requirements for hexagon and flanged hexagon nuts. WF 900 - Dimensional, material, heat treatment, hardness, and performance requirem
3、ents for flat, toothed, conical, bowed and wavy washers and their use in screw or nut and washer assemblies. ISO 261 - ISO general purpose metric screw threads - General plan. ISO 965 - ISO general purpose metric screw threads - Tolerances. ISO 1502 - ISO general purpose metric screw threads - Gaugi
4、ng. 3. DIMENSIONAL AND PERFORMANCE REQUIREMENTS. 3.1 GENERAL. Unless otherwise specified all requirements of WE900, WE910 and WF900 apply. 3.2 NUTS. 3.2.1 DIMENSIONS. 3.2.1.1 RETENTION FEATURE. The nut may incorporate a feature to retain the washer. The feature shall not protrude beyond the bearing
5、face of the assembled washer. 3.2.1.2 THREAD COUNTERSUNK. The nut must be countersunk if permitted by the washer retention method or alternatively the retention method must be such that its form facilitates easy assembly of the nut on a male thread. 3.2.1.3 LENGTH OF THREADED PORTION. The length of
6、the threaded portion shall not be less than 0.6d where d is the nominal thread diameter. 3.2.2 FORM AND POSITION TOLERANCES. The form and position tolerances for the nut component of nut and washer assemblies shall be in accordance with WE900. NOTE: All form and position tolerances may be evaluated
7、by use of an appropriate GO thread gauge that meets the requirements of ISO 1502. 3.2.3 TEST REQUIREMENTS. Test requirements, except torque/clamping force, applicable to the nut component of nut and washer assemblies may be conducted with the washer removed. 3.3 WASHERS. 3.3.1 ASSEMBLY. The nut must
8、 allow the washer to rotate, while no disassembly of the nut and washer is permissible. Initial washer adhesion is allowable per the WX100. 3.3.2 FORM AND POSITION TOLERANCES. The form and position tolerances for the washer component shall be in accordance with WF900. 3.3.3 TEST REQUIREMENTS. The washer component of nut and washer assemblies shall meet the test requirements specified in WF900 prior to assembly except for hardness which must be as specified in WF900 after assembly.
