ASME B18.2.3.7M Hex Bolt

Product Introduction of Leader-Fastener® ASME B18.2.3.7M Hex Bolt

This standard covers the complete general and dimensional data for metric hex bolts recognized as“American National Standard.”Heavy hex structural bolts as presented in this standard have been coordinated, to the extent possible, with a draft ISO proposed standard. The dimensional differences between this ANSI standard and the ISO proposal are few, relatively minor, and none will affect the functional interchangeability of bolts manufactured to the requirements of either. There will be two ISO standards for heavy hex structural bolts，with the only difference between them being length of thread. This ANSI standard is essentially identical to the proposed 1SO standard for bolts with the shorter thread lengths.

The performance grades of bolts for steel structure connection are divided into more than 10 grades such as 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9, etc. Among them, the bolts of grade 8.8 and above are made of low-carbon alloy steel or medium-carbon steel and are heat-treated (quenching, tempering), commonly known as high-strength bolts, the rest are commonly known as ordinary bolts. The bolt performance grade label consists of two parts of numbers, which represent the nominal tensile strength value and yield ratio of the bolt material respectively.

Leader-Fastener® ANSI/ASME B 18.2.3.7M - 2006 Metric heavy hex structural bolts