ASTM A354 is an ASTM International standard that defines chemical and mechanical properties for alloy steel bolts, screws, studs, and other externally threaded fasteners. It is officially titled: Standard Specification for Quenched and Tempered Alloy Steel Bolts, Studs, and Other Externally Threaded Fasteners.
This is a standard set by the standards organization ASTM International, a voluntary standards development organizations that sets technical standards for materials, products, systems, and services.
This standard defines the properties for fasteners up to 4 inches in diameter. They are not to be used in applications where they are tensioned to more than 50% of their tensile strength. In those applications structural heavy hex bolts are to be used, as defined by ASTM A490, even though they have the same strength.
|Head marking||Grade||Nominal size range [in]||Proof strength [ksi]||Yield strength (min) [ksi]||Tensile strength (min) [ksi]||Core hardness [Rockwell]|
|Grade BD||1⁄4–2-1⁄2 (inc.)||120||130||150||C33–39|
The standard also specifies what nuts are recommended for use with the defined fasteners. Note that nuts of a greater strength can also be used.
|Fastener grade & surface finish||Nut grade & style|
|BC; plain or a coating of insufficient thickness to require over-tapped nuts||C; heavy hex|
|BC; zinc-coated or a coating that requires over-tapped nuts||DH; heavy hex|
|BD; all finishes||DH; heavy hex|