Petrochemical Bolt Assembly

Petrochemical bolt assemblies are hexagon head bolts supplied with matching nuts. They are used in process plants and other industrial piping and equipment.

A petrochemical bolt assembly fastens flanged joints and equipment in process plants. It often takes two nuts and two washers, and it is tightened with a torque wrench or hydraulic tensioner. The assembly can be matched to the flange rating and gasket.

This kind of assembly is often made in alloy steel, carbon steel or stainless steel. The choice depends on the service environment and the parts being joined.

This is a general guide to checking this kind of part. It says nothing about any supplier's parts.

Ask for a mill test certificate and a certificate of conformance for the bolt and nut. On receipt, check the markings, thread condition and that the nut matches the bolt.