How many WPS can one PQR support?

There is no limit. As long as each WPS stays within the essential variable ranges qualified by the PQR, one PQR can support as many WPS documents as the shop needs. Many fabricators maintain five or more WPS off a single PQR.

Can a single PQR support both SMAW and GMAW WPS?

No. Welding process is an essential variable under AWS D1.1:2025 Table 6.6. A PQR run with SMAW can only support SMAW WPS. You need a separate PQR — and separate test coupon — for each process.

Does qualifying on a thicker test coupon always extend the thickness range upward?

Yes, but only to the limit defined by the AWS D1.1:2025 qualification range provisions. Running a 1-inch test coupon doesn't automatically qualify unlimited production thickness. Multi-pass, single-pass, and single-layer restrictions have their own ceilings.

If I change filler metal, does the existing PQR still apply?

Depends on the change. Switching to a filler of different F-number classification or a lower strength designation typically triggers requalification. Changes within the same F-number and strength level may not. Check Table 6.6 for the specific row.

Multiple WPS from one PQR: maximizing your test coupon

One PQR can support many WPS if you plan the test coupon right. Learn how essential variables in AWS D1.1:2025 Table 6.6 set the qualified range for each procedure.

One PQR is one test event — typically a groove weld coupon, a set of mechanical tests, and a bill for shop time and lab fees. That single event can either lock you into one narrow WPS or open a family of procedures covering multiple positions, thicknesses, and base metals. The difference is planning before the rod touches the coupon.

This article walks through how to structure a PQR test so that a single qualification supports the broadest possible set of WPS documents under AWS D1.1:2025.

How the WPS–PQR link works

A WPS is a written instruction document. A PQR is the test record that demonstrates the mechanical properties of the deposited weld. Under AWS D1.1:2025, every qualified WPS must cite at least one supporting PQR. The WPS is valid only if all of its welding variables stay within the ranges qualified by the cited PQR(s).

Those ranges are governed by the essential variables in AWS D1.1:2025 Table 6.6. Each row is a variable — process, filler metal classification, base metal, position, heat input limits, preheat, and so on. Change a variable beyond its qualified boundary and the PQR no longer covers the WPS. You either revise the WPS back within range or run a new PQR.

The shop goal is to choose test conditions that maximize qualified ranges on as many Table 6.6 rows as possible.

Variables you lock in at the test coupon

Welding process

Process is the first essential variable. The process used during the PQR test — SMAW, GMAW, FCAW, SAW, GTAW — is the only process that PQR can support. There is no crossover. Budget for a separate coupon if the shop runs multiple processes in production.

Exception: combination-process procedures (e.g., GTAW root / SMAW fill) require the PQR to demonstrate both processes used in production proportion. If the PQR shows only GTAW, you cannot add SMAW fill passes to the WPS without a new test event.

Thickness and joint type

The thickness of the test coupon sets the minimum and maximum production thickness the WPS can invoke. AWS D1.1:2025 provides qualification range tables that define upper and lower limits based on the tested coupon thickness. Running a thicker coupon generally extends the upper range; thinner coupons may restrict the lower end.

Practical guidance:

A 3/4 in [19 mm] coupon is a common sweet spot — it typically qualifies production weld material at or above the minimum that covers most structural steel applications, without requiring the heavy plate and high heat input of a 1-inch or thicker coupon.
If your shop regularly welds plate from 1/4 in through 1-1/2 in, a single 3/4 in coupon may cover most of that range in one test. Verify against the current qualification range table in AWS D1.1:2025.
Single-pass and single-layer welds have tighter thickness restrictions than multi-pass welds. If the PQR is run as multi-pass, the WPS must also specify multi-pass where those limits apply.

Position

Position is an essential variable. Qualifying in a more demanding position typically covers less demanding positions — qualifying in the vertical (3G) position, for example, covers the flat (1G) and horizontal (2G) positions for groove welds. Qualifying in the overhead (4G) position covers flat only.

To qualify the broadest set of positions in a single test, run the coupon in the position combination that covers all the positions you need. For most structural shops, a 3G+4G combination test is the most efficient.

Confirm the exact position coverage matrix in AWS D1.1:2025 before committing your test position — the table hasn't changed significantly between 2020 and 2025, but always verify against the edition your contract cites.

Filler metal

Filler metal classification is an essential variable. The AWS A5-series classification, F-number grouping, and strength level used during the PQR test define the filler range the WPS can invoke. Stepping outside that boundary — say, switching from an E71T-1C to an E71T-8 (different shielding type and F-number) — invalidates the PQR's support.

To cover multiple filler options on a single WPS, run the PQR with the filler that sits at the most restrictive end of what you plan to use. Document the exact AWS classification on the PQR, not just a brand name.

Preheat and interpass temperature

The minimum preheat used during the PQR test sets the minimum preheat for the supported WPS. The WPS may specify a higher preheat for a given material, but it cannot go below the PQR minimum without a new test. Run the coupon at the minimum preheat your production environment will realistically achieve on the coldest job.

Maximum interpass temperature is a separate row in Table 6.6. If your production max interpass is 550 °F [290 °C], the PQR must be run at or below that ceiling.

Heat input

AWS D1.1:2025 Table 6.6 includes heat input as an essential variable for procedures where toughness is required (CVN applications — those also fall under the supplementary essential variables in Table 6.8). For standard structural procedures without CVN requirements, heat input limits still appear on the WPS as nonessential variables, meaning they affect weld quality but don't trigger requalification on their own.

When CVN testing applies, the maximum heat input used during the PQR test becomes a hard ceiling for production WPS. Run the coupon at the highest heat input you expect in production.

Building a family of WPS from one PQR

Here's what a well-planned PQR purchase looks like in practice for a mid-size fab shop running structural steel:

One PQR test event (GMAW, 3/4 in coupon, 3G+4G position, ER70S-6, 450 °F [230 °C] max interpass):

WPS-GMAW-1: Flat/horizontal fillet and groove welds, A36 and A572 Gr. 50, up to 3/4 in plate
WPS-GMAW-2: Vertical-up groove welds, A36 and A572 Gr. 50, 3/8 in to 1-1/2 in plate
WPS-GMAW-3: Overhead groove welds, flat and horizontal filletting, same base metals, same filler

Each WPS cites the same PQR. They differ in position, weld type, and thickness range — all within the qualified envelope. The shop avoids three separate test events.

When you genuinely need a new PQR

A single PQR cannot cover every production variable. New PQRs are required when:

Switching welding process (SMAW PQR will not support a GMAW WPS)
Qualifying a base metal in a different category than tested
Using a filler with a different F-number or lower minimum tensile classification
Exceeding the qualified thickness range on the thick or thin end
Adding CVN (toughness) requirements when the original PQR did not include impact testing
Changing position beyond what the original test position qualifies
Reducing preheat below the PQR minimum

Read when does a PQR require requalification for a detailed breakdown of which changes force a new test. For the cost tradeoff between prequalified WPS and a PQR-backed qualified procedure, see PQR vs prequalified: cost comparison.

Tracking PQR-to-WPS linkage in your procedure library

As the procedure library grows, the PQR-to-WPS linkage becomes its own documentation burden. Each WPS must cite the PQR number(s) that support it. Each PQR must be accessible and legible. Third-party auditors will trace the chain.

The failure mode most shops encounter: a WPS citing a PQR that was never formally closed out (no signatures, missing test results), or a WPS that has drifted outside the PQR's qualified range because someone added a new base metal to the WPS without checking the PQR.

A digital procedure library that enforces the linkage — flagging WPS parameters that exceed the cited PQR's qualified range — is the cleaner solution. See building an audit-ready welding procedure library for what that infrastructure looks like in a production shop. If you're deciding whether to qualify now or run prequalified, the table at PQR vs prequalified cost comparison shows where each approach wins.

If your shop is ready to map your PQRs to a full matrix of WPS, WPS Welding's qualifier tool does the essential variable range checks automatically.

Summary

One PQR can legally support an unlimited number of WPS — the only constraint is the essential variable envelope it qualified. Plan the test coupon for the most demanding position, thick enough to cover your production range, at the minimum preheat production can maintain, and with the filler classification that represents your full filler inventory. Write multiple WPS off that single test record, each scoped to a specific production application. Every new PQR test is money spent; a well-planned one buys coverage for years.

Rule library based on AWS D1.1:2025; verify against your governing edition. The AHJ or contract may specify 2020 or an earlier edition, which may have different table references and qualification range values.