Under AWS D1.1, some welding procedures are prequalified — meaning you can write and use the WPS without running a destructive test. Everything else requires a PQR to qualify. ASME Section IX has no prequalified procedures at all.
What Is a Prequalified WPS?
A prequalified WPS is a welding procedure that does not require destructive testing to validate. AWS D1.1 Clause 5 defines specific limits — if every variable on your WPS falls within those limits, no test coupon or PQR is needed.
The key word is every. One variable outside the prequalified envelope and the entire procedure must be qualified by test. Here are the D1.1 prequalified limits at a glance:
| Variable | Prequalified Requirement (D1.1 Clause 5) |
|---|---|
| Process | SMAW, GMAW (except short-circuit on >3/16" vertical-down), FCAW, GTAW, or SAW only |
| Base metal | Listed in Table 5.3 — Groups I through IV |
| Filler metal | Matching filler from Table 5.4 |
| Joint details | Must match a prequalified joint configuration from Figures 5.1 through 5.4 exactly |
| Preheat | Meets or exceeds Table 5.8 minimums for the base metal group |
| Parameters | Amperage, voltage, and travel speed within Tables 5.5 through 5.7 |
| Position | All standard welding positions (1G-4G, 1F-4F) are permitted |
How Does a Prequalified WPS Compare to a Qualified WPS?
A prequalified WPS skips destructive testing. A qualified WPS requires a PQR with actual test coupon data — tensile, bends, and sometimes impacts.
| Factor | Prequalified WPS | Qualified WPS (with PQR) |
|---|---|---|
| Code basis | AWS D1.1 only | AWS D1.1, ASME IX, API 1104, any code |
| Destructive testing | None required | Required — tensile + bends minimum |
| Cost per procedure | $0 (writing time only) | $800-2,000 (coupon + lab + CWI) |
| Turnaround time | Same day | 1-3 weeks (including lab) |
| Variable flexibility | Must stay within Clause 5 limits | Anything the test data supports |
| Written WPS required? | Yes — always | Yes — always |
| Common use | Structural steel, small shops, standard joints | Pressure vessels, piping, non-standard joints |
When Do You Need a Qualified (Tested) Procedure?
You need a PQR-backed WPS any time you fall outside the prequalified envelope — or any time you're working under a code that doesn't recognize prequalified procedures.
- Any ASME Section IX work — always, regardless of process or joint type
- AWS D1.1 work with a non-prequalified variable — unlisted base metal, non-standard joint geometry, or parameters outside Table 5.5-5.7 ranges
- Dissimilar metal welds not covered by Table 5.3 groupings
- Any process not listed as prequalified — ESW, EGW, laser, etc.
- When the contract or engineer of record requires it — some owners require PQR-backed procedures even when prequalified would suffice
Shops that do both structural and pressure work need to manage both types. Keeping your welder continuity current across all qualified processes is critical regardless of which WPS type you use.
What Does Qualification Cost?
A PQR typically costs $800-2,000 total. Here is the breakdown:
| Cost Item | Typical Range |
|---|---|
| Material and welding time | $200-500 |
| Lab testing (tensile + bends) | $300-800 |
| Impact testing (if required) | $200-400 additional |
| CWI witness time | $100-300 |
| Total per PQR | $800-2,000 |
This is why small shops lean heavily on prequalified procedures when working under D1.1. A shop running 10 different joint configurations could save $8,000-20,000 or more by staying within prequalified limits.
What Are the Most Common Prequalified WPS Mistakes?
The number one mistake is calling a procedure prequalified when it isn't. If even one variable is outside the Clause 5 limits, you need a PQR.
- Non-matching joint geometry. The joint must match Figures 5.1-5.4 exactly — root opening, groove angle, root face. A "close enough" joint detail that doesn't match a prequalified figure voids the prequalified status
- Skipping the written WPS. "Prequalified" does not mean "no WPS needed." You still need a written document on the shop floor. This is a frequent audit finding
- Exceeding parameter limits. The prequalified amperage and voltage ranges in Tables 5.5-5.7 are tighter than many welders expect. Running 5 amps over the limit voids the prequalified status
- Wrong filler metal group. The filler must come from Table 5.4 and match the base metal group. Using a filler outside this table — even if it's technically compatible — means you need a PQR
Frequently Asked Questions
Does ASME Section IX allow prequalified WPSs?
No. ASME Section IX has no prequalified procedures. Every WPS under ASME must be backed by a PQR with actual destructive test data — tensile and bend tests at minimum. This applies regardless of process, base metal, or joint type. There are no exceptions.
What happens if one variable on a prequalified WPS falls outside D1.1 limits?
The entire WPS loses its prequalified status. Even a single variable outside the limits in AWS D1.1 Clause 5 — such as a non-standard joint geometry, an unlisted base metal, or exceeding the parameter ranges in Tables 5.5-5.7 — means you need a PQR with destructive test data to qualify the procedure.
How much does it cost to qualify a WPS with a PQR?
A typical PQR costs $800-2,000 total. That includes $200-500 for materials and welding time, $300-800 for lab testing (tensile + bends), $200-400 for impact testing if required, and $100-300 for CWI witness time. Turnaround is typically 1-3 weeks including lab scheduling and report preparation.
Build prequalified WPSs that pass inspection
WeldPad flags when your parameters fall outside prequalified limits. Write procedures you're confident in.
Try WeldPad Free