ASME Section IX sets out how welding, brazing and fusing procedures — and the people who carry them out — are qualified before they are used on code-covered pressure equipment. This overview summarizes its purpose and structure; it does not replace the official standard.
Overview
Section IX is part of the ASME Boiler and Pressure Vessel Code. It defines the qualification requirements referenced by other Code sections whenever welding, brazing or fusing is used to fabricate or repair pressure-retaining equipment.
Scope
It applies to the qualification of welding and brazing procedures, and of the welders, brazers and operators who use them, across the range of processes and materials covered by the Code. It does not itself specify design or fabrication rules — those live in the Code sections that reference it.
Qualification Framework
Qualification is organized around two related but distinct questions: whether a procedure produces sound welds under given conditions, and whether an individual can execute that procedure reliably. Section IX addresses both through separate qualification records.
Procedure Qualification
A Procedure Qualification Record documents a test weld made under a specific set of variables — material, process, position, filler metal and more — and the mechanical testing that confirms it meets required properties. The result supports a Welding Procedure Specification.
Performance Qualification
Separately, each welder or operator demonstrates the ability to produce acceptable welds within a qualified procedure's range, recorded on a Welder Performance Qualification. This record is what is checked, not the procedure record, when confirming an individual's authorization to weld.
Relationship to Other Standards
Section IX is referenced by fabrication codes such as AWS D1.1 in specific circumstances, and its qualification logic parallels — without being identical to — the approach taken by ISO 9606-1 for welder qualification. Which standard governs a given job depends on the applicable code or contract.
References
This page is an original, summary-level overview prepared for orientation purposes. It is not a substitute for the official ASME Boiler and Pressure Vessel Code, Section IX, which should be consulted directly for any actual qualification work.