This paper was prepared to support supersession of MIL-S-8879C with Screw Thread Conformity Task Force selected industry standard AS8879C, published by the Society of Automotive Engineers (SAE). Other documentation changes will be covered by separate papers. Separate papers are anticipated for thread gaging issues, and thread gage calibration procedures. The STC-TF decided that the thread design standard needed to be completed before thread gage definition could be addressed. Thread gage definition has to be known before calibration procedures can be addressed.
This procurement specification covers plain helical lock washers made of corrosion-resistant steel of the type identified under the Unified Numbering System as UNS S30200. Primarily for use with corrosion-resistant steel threaded fasteners; not recommended for use at temperatures higher than 700 °F (370 °C).