ASTM A563 & A563M HEAVY HEX NUT
This ASTM A563 and ASTM A563M heavy hex nuts specification covers chemical and mechanical requirements for eight property classes of hex and hex-flange carbon and alloy steel nuts for general structural and mechanical uses on bolts, studs, and other externally threaded parts.
Note 1: Throughout this specification, the term class means property class.
Note 2: Requirements for the four classes 5, 9, 10, and 12 are essentially identical with requirements given for these classes in ISO 898/II. Requirements for Classes 8S and 10S are essentially identical with requirements in an ISO 4775 Hexagon Nuts for High-Strength Structural Bolting with Large Width Across Flats, Product Grade B, Property Classes 8 and 10. Classes 8S3 and 10S3 are not recognized in ISO standards.
1.2 Classes 8S3 and 10S3 nuts have atmospheric corrosion resistance and weathering characteristics comparable to those of the steels covered in Specification A 588/A 588M. The atmospheric corrosion resistance of these steel’s substantially is better than that of carbon steel with or without copper addition. and when properly exposed to the atmosphere, these steels can be used bare (un-coated) for many applications.
1.3 The nut size range for which each class is applicable is given in the table on mechanical requirements.