B7 / 2H

Piping

The standard piping bolt pair: ASTM A193 Gr B7 studs with ASTM A194 Gr 2H nuts. Studs and nuts are specified together and are not interchangeable. The M-suffixed versions (B7M / 2HM) are softened to meet the NACE hardness limit for sour service.

Explained in depth

Gaskets and bolting — why most flange leaks are assembly, not hardware

Related terms

Gasket seating stress
Hot bolting
Spiral wound gasket
Air-to-open
Anchor
Anti-surge control
Area replacement
BEP
Bevel
Check valve slam
Clad plate
Corrosion allowance