Originally approved in 1936, this specification is heavily utilized in petroleum
and chemical construction applications.
alloy steel and stainless steel bolting materials for
high temperature service. This specification
includes fasteners intended for use in
pressure vessels, values, flanges, and fittings. Although, this material is often
available to national coarse (UNC) thread pitches, if being used in traditional
applications, threads are specified 8 threads per inch (tpi) for diameters above one
Below is a basic summary of a few of the common grades. ASTM A193 covers a number
of other standard specifications
not covered in
this description including B5, B6, and B16.