1.1 This specification covers the chemical and mechanical requirements for two types of quenched and tempered steel bolts and studs for general applications where high strength is required.
1.2 The two types of bolts covered in this specification are:
1.2.1 Type 1 -Medium-carbon steel bolts and studs furnished in nominal diameters of 1/4 to 3 in., inclusive.
1.2.2 Type 2 -Low-carbon martensite or medium-carbon martensite steel bolts and studs furnished in nominal diameters of 1/4 to 1 in., inclusive.
1.3 The bolts and studs shall be Type 1; Type 2; or, Type 1 or 2 at manufacturer’s option; as specified by the purchaser. When a type is not specified, Type 1 shall be furnished. When elevated temperature applications are involved, Type 1 shall be specified by the purchaser on the order.
1.4 Suitable nuts are covered in Specification A563. Unless otherwise specified, the grade and style of nut shall be as follows:
Fastener Size and Surface Finish Nut Grade and Style A 1/4 to 1 1/2 in., plain (or with a B, hex coating of insufficient thickness to require over-tapped nuts) Over 1 1/2 to 3 in., plain (or with A, heavy hex a coating of insufficient thickness to require over-tapped nuts) 1/4 to 3 in., zinc-coated (or with DH, heavy hex a coating thickness requiring over-tapped nuts) A Nuts of other grades and styles having specified proof load stresses (Specification A 563, Table 3) greater than the specified grade and style of nut are suitable.
1.5 Unless otherwise specified, washers ordered with bolts shall be furnished to the requirements of Specification F436.
1.6 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are provided for information purposes only.