WPS, PQR & Welder Qualification: Welding to a Qualified Procedure

Welcome

Hello, and welcome. This is Super Structures General Contractors — a national general contractor headquartered in Powhatan, Virginia — here to help you and your clients build something that lasts. We're glad you're with us, and we look forward to connecting with you.

Alright, WPS, PQR & Welder Qualification: Welding to a Qualified Procedure. Don't let the plain title fool you. Here's the part that actually matters on the job: Every structural weld is made to a written, qualified procedure by a welder who is qualified to that procedure, and the paperwork proving both has to exist before the arc strikes. Learn it well and you will never be the welder whose work gets cut out because nobody could prove it was made right.

The intro course covered the processes and the tests a welder passes. This lesson is about the system that ties those together on a structural job: the welding procedure specification (WPS), the procedure qualification record (PQR) behind it, and the welder performance qualification that says a specific person may weld to it. On any job governed by AWS D1.1, Structural Welding Code — Steel, those three documents are the foundation of every weld.

What a WPS is and what it must say

A WPS is a one- or two-page written recipe for a specific weld. It tells the welder and the inspector exactly how the weld is to be made and leaves nothing to memory. A complete WPS lists:

• Process — SMAW, FCAW-S, FCAW-G, GMAW, or SAW.
• Base metal — the steel grade or D1.1 group (A36, A992, A572 Gr. 50, A500) and the thickness range covered.
• Filler metal — the AWS classification (E7018, E71T-1C, E70T-6), diameter, and for gas-shielded processes the shielding gas and flow rate.
• Joint design — groove type, angle, root opening, root face, backing or backgouge.
• Position and progression, preheat and interpass limits, and technique — stringer or weave, number of passes, interpass cleaning.
• Electrical characteristics — current type and polarity, and the amperage, voltage, and travel speed range for each pass. The ranges on the card are not suggestions. A weld made outside them is nonconforming even if it looks perfect.

Prequalified versus qualified by test

D1.1 offers two paths to a valid WPS. A prequalified WPS needs no testing because it stays inside limits the code has already proven: a prequalified process (SMAW, GMAW except short-circuit transfer, FCAW, and SAW), a listed base metal, a prequalified joint detail, matching filler metal, and preheat at or above the code's table. Most structural field work runs on prequalified WPSs written by the contractor's welding engineer or CWI.

Anything outside those limits — short-circuit GMAW on structural steel, an unlisted steel, a joint geometry not in the code, a lower preheat than the table — must be qualified by test. The contractor welds a test plate exactly as the proposed WPS says, a lab cuts it into tension, bend, and macroetch specimens, and the actual values used and the results go onto a PQR. The PQR is a record of a test and never changes; the WPS is an instruction and can be revised as long as it stays inside what the PQR proved.

Welder performance qualification

A WPS says how; the welder performance qualification record says who. A welder tests by welding a coupon under a WPS while a CWI or the employer's representative witnesses it, then the coupon is bent or inspected to the code's criteria. The record ties the welder to a process, a position range, and a thickness range:

• Positions — a 3G (vertical) plate groove test qualifies flat, horizontal, and vertical; a 4G (overhead) test qualifies flat and overhead. The classic 3G plus 4G combination covers all plate positions for groove and fillet welds.
• Thickness — a 3/8 in. test plate qualifies up to 3/4 in. of production material; a 1 in. test plate qualifies unlimited thickness.
• Process — qualification is by process. A stick test does not cover flux-core, and vice versa.
• Continuity — under D1.1 a qualification stays in effect indefinitely unless the welder has not used that process for more than six months, or there is a specific reason to question the welder's ability. Employers keep a continuity log proving the six-month clock never ran out. Tack welders qualify too, with a simpler test. Qualification records belong to the employer who ran the test; most structural contractors retest every new hire on the first day.

The documents on the job

Before the first production weld, the contractor's quality control inspector confirms three things: the WPS covering each joint is on site and matches the drawing detail, each welder has a current qualification for that WPS, and the consumables on the truck match the WPS. The owner's special inspector under IBC Chapter 17 and AISC 360 Chapter N verifies the same before and during welding.

Going Deeper (Intermediate)

Foremen manage the crew by qualification. A typical structural crew runs FCAW-S for production field welds and E7018 for tacks, repairs, and tight spots, so each welder needs both. The foreman keeps a one-page matrix of welders against WPS numbers and assigns work from it. When a new joint shows up, the first question is whether a WPS exists and the welder is qualified to it. Filler metal must match the base metal as the code tables require; E70-class consumables are the standard match for A36, A992, and A572 Gr. 50. Seismic connections add AWS D1.8 requirements for filler metal toughness on demand-critical welds.

Advanced / Pro-Level

Pros read the PQR behind a qualified WPS, not just the WPS. They check that the production joint is within the PQR's thickness and position ranges and that the heat input in production, volts times amps times 60 divided by travel speed in inches per minute, stays within the range the test proved. They know D1.1 is one of a family — D1.3 for sheet steel and deck, D1.4 for reinforcing bar, D1.6 for stainless, D1.8 for seismic — and that qualification under one does not carry to another. They resolve every objection to the WPS package at the preconstruction meeting, because a rejected WPS after steel is hung stops the job.

Practice Challenge

A new welder arrives with a current AWS Certified Welder card for SMAW, 3G, on 3/8 in. plate. Today's work is FCAW-S complete-joint-penetration flange welds on 1 in. material, half of them overhead. What does the foreman do? (Answer: the welder cannot make those welds — the process, thickness, and position are all outside the qualification. Either test the welder on FCAW-S in 3G and 4G on 1 in. plate to the company WPS, or assign SMAW fillet and tack work within the existing qualification until the test is complete.)

In Practice

A foreman who keeps the WPS binder current, the matrix updated, and the continuity log signed never loses a day to an inspector's question. A foreman who assumes a good welder is a qualified welder finds out that twenty finished welds have no paper behind them.

Common Mistakes to Avoid

• Welding to a WPS that is not on site, or to no WPS at all
• Treating a qualification in one process as cover for another process
• Letting a qualification lapse by missing the six-month continuity log
• Running amperage or voltage outside the WPS range because the weld looks fine

Takeaway: Every structural weld is made to a written, qualified procedure by a welder who is qualified to that procedure, and the paperwork proving both has to exist before the arc strikes.

Educational content only — not engineering, design, inspection, or safety advice, and not a substitute for hands-on training, a qualified welding procedure, or a licensed professional. Weld to the WPS and the drawings, follow AWS D1.1, AISC, and OSHA requirements as adopted and applied on your project, and follow the manufacturer's instructions for your equipment and consumables.