Bolt standard ASTM A490
ASTM A490 Covers heavy hex bolts also known as structural bolts made of alloy steel with minimum 150 ksi strength.
ASTM A490 bolts are designed for building structures and usually are partially threaded with a shank longer than standard hex bolts. ASTM A490 standard bolts are very closed in structure and application to A325, However they have higher tensile and strength. This standard of hex bolts should not be processed for hot deep galvanization to avoid hydrogen embrittlement. Therefore, in case of requirement for coating Dacromet coating is recommended.
Mechanical properties of ASTM A490 bolts are as follows:
|Size in||Tensile ksi||Proof load ksi||Elongation %|
|1/2 - 1 1/2||min 150-173||130||14|
Four different types of ASTM A490 standard bolts are manufactured
|Type 1||Alloy steel or medium carbon steel |
|Type 2||Withdrawn since 2002|
|Type 3||Weathering steel|
|M||A490 Metric standard|
Also, this standard of bolts require special standard of nuts and washers that are in the table below:
Bolt and nut
|Type 1||Type 3||type 1||Type 3|