Originally approved in 1936, this specification is heavily utilized in petroleum and chemical construction applications. The ASTM standard covers alloy steel and stainless steel bolting materials for high temperature or high-pressure service. This specification includes fasteners intended for use in pressure vessels, valves, flanges, and fittings. Although, this material is often available in national coarse (UNC) thread pitches, if being used in traditional applications, threads are specified 8 threads per inch (tpi) for diameters above one inch.
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.
A193 Grades
B7
Alloy steel, AISI 4140/4142 quenched and tempered
B8
Class 1 Stainless steel, AISI 304, carbide solution treated.
B8M
Class 1 Stainless steel, AISI 316, carbide solution treated.
It's no secret that we are known as experts in the fastener industry and have been since 1912. Our devotion to customer service, quality products, and on-time deliveries have propelled us to success since our inception.
