API Recommended Practice 582 provides supplementary guidelines and practices for welding and welding related topics for shop and field fabrication, repair and modification of the following:

-pressure-containing equipment such as pressure vessels, heat exchangers, piping, heater tubes, and pressure boundaries of rotating equipment and attachments welded thereto;
-tanks and attachments welded thereto;
-nonremovable internals for process equipment;
-structural items attached and related to process equipment;
-other equipment or component item when referenced by an applicable purchase document.

This document is general in nature and is intended to augment the welding requirements of ASME BPVC Section IX and similar codes, standards, specifications and practices such as those listed in Section 2. The intent of this document is to be inclusive of chemical, oil and gas industry standards, although there are many areas not covered herein, e.g. pipeline welding and offshore structural welding are intentionally not covered.

This document is based on industry experience and any restrictions or limitations may be waived or augmented by the purchaser.