6.3 Welder Performance Qualification (WPQ)
Key Takeaways
- A WPQ qualifies the welder's SKILL; a PQR qualifies the PROCEDURE — both are required before production
- WPQ uses bend, radiography, macro-etch, or fillet-break tests (always VT first) — never tensile tests
- Position follows 'harder qualifies easier': 6G pipe, or 3G + 4G plate, qualifies ALL positions (Table 6.10)
- A 1 in (25 mm) test plate qualifies unlimited production thickness (Table 6.11), like the PQR rule
- Clause 6.4.1: qualification lapses after 6 months of process inactivity, but one retest restores all positions; the CWI verifies each WPQ covers the production process, position, thickness, and filler
What a WPQ Is
A Welder Performance Qualification (WPQ) — also called a welder qualification test record — verifies that an individual welder has the skill to deposit sound weld metal following a WPS. This is a fundamental distinction the CWI exam hammers: a PQR qualifies the procedure, while a WPQ qualifies the person. Both must exist before production: the procedure must be proven capable, and each welder must be proven able to execute it.
The welder makes a test coupon under a qualified WPS; the coupon is then evaluated. Because the goal is to judge soundness of deposit (not the joint's strength — that was already proven by the PQR), the WPQ relies on bend tests, radiography, macro-etch, or fillet break tests, not tensile tests.
| Feature | PQR (Procedure) | WPQ (Welder) |
|---|---|---|
| What is qualified | The welding procedure/variables | The individual welder's skill |
| Typical tests | Tensile + bend (+ CVN if specified) | Bend or RT; macro/break for fillets; always VT first |
| Scope | One per procedure | One per welder, per process, per position group |
| Lapses? | No — only on essential change | Yes — by inactivity (6-month rule) or quality concern |
WPQ Test Methods
| Method | When Used |
|---|---|
| Visual (VT) | Always first — gross defects fail the coupon before destructive testing |
| Guided bend | Standard for groove qualification (root/face, or side bends for thicker plate) |
| Radiography (RT) | Permitted in lieu of bends for groove coupons under D1.1 |
| Macro-etch | Fillet weld qualification — checks fusion and profile on a cut cross-section |
| Fillet break test | Fillet coupon is fractured and the exposed surface examined for soundness |
Position Qualification Ranges (Table 6.10)
Welding position is an essential variable for the welder, and the code follows a "harder qualifies easier" logic. Vertical (3G) and overhead (4G) are the difficult positions, so qualifying in them extends to flat and horizontal.
| Test Position(s) | Production Positions Qualified |
|---|---|
| 1G (flat plate) | Flat groove only |
| 2G | Flat + horizontal |
| 3G + 4G (plate) | All positions (flat, horizontal, vertical, overhead) |
| 6G (pipe, 45° fixed) | All positions — the most versatile single test |
A welder who passes a 6G pipe test, or a 3G plus 4G plate combination, is qualified for all groove and fillet positions — the most exam-cited fact in this topic.
Thickness Qualification (Table 6.11)
| Test Plate Thickness (T) | Production Thickness Qualified |
|---|---|
| 1/8 in (3 mm) ≤ T < 1 in (25 mm) | 1/8 in (3 mm) min to 2T max |
| T ≥ 1 in (25 mm) | 1/8 in (3 mm) min to unlimited |
A welder tested on a 1 in plate is therefore qualified for unlimited thickness — mirroring the PQR rule and frequently tested side by side with it.
Essential Variables for the Welder
| Essential Variable | Change Requiring Requalification |
|---|---|
| Process | SMAW → GMAW, or any process switch |
| Position | Adding a position not covered (per Table 6.10 logic) |
| Filler F-number | Moving to a higher/different F-number group |
| Vertical progression | Uphill ↔ downhill |
| Backing | Removing backing (welding without it) when qualified with it |
| Thickness | Production thickness outside the qualified range |
Maintaining Qualification — The 6-Month Rule
Per AWS D1.1 Clause 6.4.1, a welder's qualification stays valid as long as: (1) the welder has used that process within the previous 6 months; (2) there is no specific reason to question the welder's ability (e.g., repeated rejects); and (3) the essential variables have not changed beyond range. If the 6-month activity lapses, qualification expires for that process — but a single requalification coupon (e.g., on a 1 in plate) can restore all positions.
Diameter, Backing, and Record Contents
For pipe and tube, qualification also depends on outside diameter, and the CWI checks the diameter range as carefully as the thickness range. The backing condition matters too: a welder qualified with backing is not automatically qualified to weld without backing (an open-root joint), because the open-root root pass is a distinct, harder skill — a frequent exam distractor. A complete WPQ record documents the welder's stamp, the WPS followed, the actual process/position welded, base and filler metals, coupon thickness/diameter, test method and results, the qualified ranges, and the witnessing signatory.
Like the PQR it is a historical record, but unlike the PQR it has a shelf life governed by the 6-month activity rule.
The CWI's Role
The CWI's job in performance qualification is verification, not training or welding. Before and during production the inspector confirms each welder's WPQ record is current and covers the process, position, thickness range, diameter, filler F-number, and backing condition of the actual production joint. A welder qualified only on 3G plate cannot be assigned overhead production without 4G coverage; a welder qualified only with backing cannot be put on open-root work; a CWI who allows either has failed the core duty.
The inspector also confirms the welder's continuity (that the 6-month rule has not lapsed) and that no quality concern has invalidated the qualification.
Exam trap: Do not confuse the documents — PQR qualifies the procedure; WPQ qualifies the welder. And remember the qualification restores after a lapse with one retest; lapsing does not erase the welder's history, only the current validity.
Per AWS D1.1 Clause 6.4.1, a welder's qualification for a given process lapses if the welder has not used that process within the previous:
Which single welder test coupon qualifies a welder for ALL groove and fillet positions under AWS D1.1?
What is the CWI's primary responsibility regarding welder performance qualification?
Which of the following is an ESSENTIAL variable for welder performance qualification (would require requalification if changed beyond range)?