Can an AWS B2.1 PQR be used directly for AWS D1.1 structural work?

Not automatically. The engineer of record or owner must explicitly accept the B2.1 PQR, and the test variables must satisfy all AWS D1.1:2025 essential variable requirements — including base metal group, position, and any CVN toughness testing required by contract.

What is the main difference between AWS B2.1 and AWS D1.1 qualification systems?

AWS B2.1 is a general-purpose qualification standard covering any weldment; AWS D1.1 is code-specific to structural steel and includes structural-specific variables such as weld pass sequence documentation, prequalified joint allowances, and base metal group tables unique to D1.1.

Do AWS B2.1 WPS essential variables match AWS D1.1 Table 6.6?

Partially. Both standards track process, filler metal classification, position, and preheat, but AWS D1.1:2025 Table 6.6 includes structural-specific entries — the electrode-to-supplemental-filler ratio rule, the -G designator requirement, and A5.36 exclusions — that B2.1 may not address.

What documentation should accompany a B2.1 PQR submitted for structural work?

At a minimum: the complete PQR test record including mechanical test results, welder certification that the test was produced under the qualified variables, and written acceptance from the engineer of record confirming the B2.1 parameters satisfy the D1.1 essential variable envelope.

Oct 19, 20266 min read

AWS B2.1 WPS vs. AWS D1.1 PQR: Cross-Code Portability

Learn when AWS B2.1 welding procedure qualifications can transfer to AWS D1.1 structural steel work, and the essential variables that prevent direct reuse.

WPS PQR AWS D1.1 AWS B2.1 Qualification Structural Welding

Many structural fabricators also perform pressure vessel, piping, or process equipment work under ASME Section IX or AWS B2.1 qualifications. When a shop lands a structural steel contract governed by AWS D1.1:2025, the first question is always the same: Can we use the PQRs we already have, or do we need to re-qualify from scratch?

The answer is "sometimes yes, but verify every essential variable before assuming." Here is what you need to know.

What Each Standard Covers

AWS B2.1, Specification for Welding Procedure and Performance Qualification, is a general-purpose qualification document. It establishes a framework for writing WPS and conducting PQR tests that can be referenced by any applicable fabrication code — structural, pressure, piping, or other. B2.1 is not a fabrication code itself; it defines how qualification is structured, not what acceptance criteria govern the finished weld.

AWS D1.1:2025, Structural Welding Code — Steel, is a complete fabrication code. Chapter 6 governs procedure and performance qualification for structural steel welds. D1.1 incorporates its own essential variable tables, its own mechanical test requirements, and structural-specific rules not present in B2.1. When a contract references AWS D1.1, Chapter 6 is the controlling qualification authority unless the engineer of record writes a project specification that explicitly allows something different.

The critical distinction: satisfying B2.1 does not automatically satisfy D1.1. Satisfying D1.1 typically satisfies B2.1 because D1.1 is more restrictive in several structural-specific areas.

Essential Variables: Where the Gap Opens

AWS D1.1:2025 Table 6.6 lists essential variables for the common arc welding processes — SMAW, SAW, GMAW, FCAW, and GTAW. Rule library based on AWS D1.1:2025; verify against your governing edition. A B2.1 PQR may cover the same variable categories but miss several that are structural-code-specific:

Filler metal classification details. D1.1:2025 Table 6.6 row 4 excludes A5.36 dual-classification electrodes from the GMAW/FCAW allowed list — a 2025 change not present in older editions or in B2.1. If your B2.1 PQR was run with an A5.36-classified electrode, it may not qualify under the current D1.1 essential variable envelope.

Electrode-to-supplemental-filler ratio. Table 6.6 row 7 introduced a ±10% threshold on the ratio of electrode to supplemental filler wire in tandem or twin-arc processes. B2.1 does not capture this ratio as a tracked variable.

The -G designator rule. Table 6.6 row 8 governs qualification coverage when the electrode carries a -G (user-defined chemistry) suffix. This is new in 2025 and has no equivalent in B2.1.

CVN supplementary essential variables (Table 6.8). When a project requires notch toughness qualification — demand-critical welds, seismic applications under D1.8, or low-temperature service — D1.1:2025 Table 6.8 lists additional essential variables that control the HAZ and weld metal toughness. B2.1 has CVN provisions, but the specific triggers, the minimum thickness floor of 1/2 in [12 mm] for Table 6.8 row 2(a), and the interpass maximum increase rule at Table 6.8 row 8 reflect 2025-edition structural content that a pre-2025 B2.1 PQR would not have been written to satisfy.

When Cross-Code Reuse Is Defensible

A B2.1 PQR can support a D1.1 WPS when all of the following are true:

Every D1.1 essential variable is addressed. Walk Table 6.6 row by row and confirm the B2.1 PQR recorded a value within the qualified range for each entry. Pay special attention to the 2025-specific rows noted above.
Mechanical test results meet D1.1 requirements. D1.1 Chapter 6 specifies tensile strength, guided bend, and — when applicable — CVN test requirements with specific specimen orientation, test temperature, and minimum absorbed energy values. If your B2.1 PQR used different test procedures or acceptance thresholds, the results may not be transferable.
The engineer of record (EOR) accepts it in writing. AWS D1.1 does not prohibit a fabricator from presenting B2.1 PQR test data to an EOR for review. If the EOR is satisfied that the qualification envelope covers the production variables and the mechanical tests meet D1.1 minima, they can issue written acceptance. Document this acceptance and keep it with the WPS package. Without EOR written acceptance, the PQR is not compliant with D1.1.
No project-specific supplements override it. AISC 341 seismic provisions, AISC 358 prequalified moment connections, or owner supplements may impose stricter testing requirements than D1.1 alone. A B2.1 PQR is unlikely to have been written with seismic-specific CVN, PFMR (project filler metal requirements), or weld wire lot testing in mind.

For more on how essential variables work within D1.1, see WPS essential variables vs. nonessential variables and the prequalified vs. qualified-by-test comparison.

Common Failure Modes When Reusing B2.1 PQRs

Base metal group mismatch. D1.1 organizes structural steels into groups based on yield strength and chemistry per the prequalified base metals table. A B2.1 PQR written for a P1 ASME group carbon steel covers different steel grades than a D1.1 Group I qualification. The grain structure, weld heat response, and mechanical test values may be similar, but the code traceability is not.

Position qualification coverage. B2.1 and D1.1 use similar position test coverage tables, but the D1.1 table governs when D1.1 is the referenced code. A B2.1 2G test qualifies 1G and 2G in B2.1. Confirm D1.1 Chapter 6 gives the same coverage — it largely does, but check against the actual structural code table rather than assuming.

Thickness and diameter ranges. D1.1 has specific thickness qualification ranges for groove welds. If the B2.1 PQR test plate thickness was selected for a piping application, it may fall outside the D1.1 thickness coverage for structural plate.

Missing pass-by-pass records. D1.1 requires the WPS to document welding sequence for multipass joints. B2.1 PQR test records may not have been captured at the level of detail D1.1's documentation requirements expect.

Supplemental Testing vs. a New D1.1 PQR

When a B2.1 PQR is close but not quite, supplemental testing is often faster than a full new PQR:

Mechanical test supplements: If the original B2.1 PQR test plate was retained, you may be able to cut additional CVN specimens from existing material to satisfy Table 6.8 requirements. Confirm specimen location requirements with D1.1 Chapter 6 before cutting.
Re-run of a single essential variable change: If the only gap is the A5.36 filler metal exclusion, switching to a conforming electrode classification and running a targeted qualification can be completed quickly.
EOR-driven supplemental tests: The EOR may specify exactly which additional tests will bring the existing PQR into conformance for a particular project. This is common on negotiated or design-build structural contracts where the EOR has direct involvement in the quality program.

A full new D1.1 PQR is cleaner from a records standpoint, especially if the shop anticipates ongoing structural work. A purpose-built D1.1 PQR eliminates the EOR-acceptance step on every future project. If cost and schedule permit, the new PQR investment typically pays back within one or two structural jobs.

For a review of how D1.1 PQR records fit into your overall welding documentation program, see the WPS vs. PQR vs. WPQ explainer.

Putting It Into Practice

Before submitting a B2.1 PQR for a structural D1.1 project, document the following in a cover memo to the EOR:

Copy of the B2.1 PQR with all recorded essential variables highlighted
Side-by-side comparison to D1.1:2025 Table 6.6 (and Table 6.8 if CVN is required)
Complete mechanical test results from the B2.1 qualification test
Identification of any variable gaps and how they are addressed
Proposed production WPS referencing the B2.1 PQR (plus any supplemental tests)

The EOR can review this package in a single sitting and issue written acceptance or identify specific supplemental tests. This structured approach avoids surprises at the fabrication audit and keeps the qualification record traceable to a specific project approval.

Need to build or manage your D1.1 WPS and PQR library from a single platform? WPS Welding lets you track qualification records, cross-check essential variables, and generate Annex M-formatted WPS documents across all your structural projects.

Rule library based on AWS D1.1:2025; verify against your governing edition (the AHJ or contract may specify 2020 or earlier).

FAQ

Frequently asked.

Can an AWS B2.1 PQR be used directly for AWS D1.1 structural work?: Not automatically. The engineer of record or owner must explicitly accept the B2.1 PQR, and the test variables must satisfy all AWS D1.1:2025 essential variable requirements — including base metal group, position, and any CVN toughness testing required by contract.
What is the main difference between AWS B2.1 and AWS D1.1 qualification systems?: AWS B2.1 is a general-purpose qualification standard covering any weldment; AWS D1.1 is code-specific to structural steel and includes structural-specific variables such as weld pass sequence documentation, prequalified joint allowances, and base metal group tables unique to D1.1.
Do AWS B2.1 WPS essential variables match AWS D1.1 Table 6.6?: Partially. Both standards track process, filler metal classification, position, and preheat, but AWS D1.1:2025 Table 6.6 includes structural-specific entries — the electrode-to-supplemental-filler ratio rule, the -G designator requirement, and A5.36 exclusions — that B2.1 may not address.
What documentation should accompany a B2.1 PQR submitted for structural work?: At a minimum: the complete PQR test record including mechanical test results, welder certification that the test was produced under the qualified variables, and written acceptance from the engineer of record confirming the B2.1 parameters satisfy the D1.1 essential variable envelope.