Resources
The words this industry uses without explaining them
Written for the person who has to produce the document, not for the person who already knows what it is called.
- Acceptance criteria The published limits that decide whether an indication in a weld is accepted or rejected — the line between a feature you record and a defect you repair.
- Concession A documented agreement by the client to accept something that does not conform to the specification, without it being corrected.
- Continuity (of qualification) Evidence that a welder has used a process within the required interval, without which a qualification lapses even though its expiry date has not passed.
- Essential variable A welding variable whose change requires the welding procedure to be requalified, because it materially affects the mechanical properties of the joint.
- EXC — Execution Class The class (EXC1 to EXC4) that sets how strictly a welded steel structure must be made and proven — how much is inspected, at what NDT extent, and how much of the record is kept.
- Filler metal (consumable) The added metal that fuses the joint — electrode, wire or rod — carrying its own certificate, batch and, for some types, a baking and handling regime.
- Heat number The identifier of a batch of metal as poured by the mill, and the key that ties a finished component back to a certified chemistry and set of mechanical properties.
- Hold point A point in an inspection and test plan beyond which work must not proceed until the nominated party has attended and released it.
- Inspection document (2.1, 2.2, 3.1, 3.2) The four types of material inspection document defined by EN 10204, distinguished by who performed the inspection and how independent they were.
- ITP — Inspection and Test Plan The document that sets out what will be inspected or tested, when, against which criteria, and what level of intervention each party has at each step.
- MDR — Manufacturing Data Report The documentation package delivered with manufactured equipment, often used interchangeably with MRB and sometimes covering a wider scope including design documents.
- MRB — Manufacturing Record Book The compiled evidence pack handed to the client at the end of a fabrication contract, proving that what was built was built as specified.
- NCR — Nonconformance Report The record of something that did not meet its requirement, what was decided about it, and by whom.
- PQR — Procedure Qualification Record The record of a welded test piece and the tests performed on it, from which the range a welding procedure may be used over is derived.
- Traceability The unbroken chain that ties a finished weld back to the material heat, the consumable batch, the welder, the procedure and the inspection that accepted it.
- Witness point A point in an inspection and test plan where a nominated party is invited to attend, but where work may continue if they do not.
- WPQ — Welder Performance Qualification The record that a specific welder demonstrated the ability to produce sound welds within a defined range. Sometimes called a welder certificate or, under ISO, a qualification certificate.
- WPS — Welding Procedure Specification The document that tells a welder how to make a weld: process, materials, joint preparation, position, parameters, preheat and any post-weld heat treatment.