What's the most common WPS audit finding?

A superseded revision in use on the shop floor — the current revision was issued but never replaced the printed binder copy. This single finding fails more audits than any other.

Are single-value amperages really a violation?

Yes. A WPS must specify a range for amperage, voltage, and travel speed. A single value is interpreted as both the minimum and maximum, which constrains the welder unrealistically and is technically a deficiency.

How does the rule engine catch these before an audit?

A WPS tool that encodes Tables 6.6 and 6.8 essential variables checks every value against its qualified range, flags missing fields, validates joint details against Annex B, and warns when the cited code edition doesn't match the table numbering used.

10 common WPS mistakes that fail QC review

The same WPS deficiencies show up audit after audit. Here are the ten most common, in order of frequency — and the one-line fix for each.

Across hundreds of third-party audits, the same WPS deficiencies show up over and over. None of them are subtle. All of them are preventable. Here are the ten most common, with the one-line fix.

1. Superseded revision in production

The current revision was issued in QC but the printed binder on the shop floor still has Rev 1. Welders are working to a stale procedure.

Fix: A controlled-copy log, or a digital library where the floor terminal always pulls the current revision.

2. Cited table numbers don't match the cited edition

WPS header says "AWS D1.1:2025" but the document cites "Table 6.5 essential variables" — that was the 2020 number. In 2025 the table is 6.6.

Fix: Bulk-update table citations when migrating editions.

3. Single-value amperage instead of a range

The WPS lists "Amperage: 130 A" instead of "Amperage range: 115–145 A." Single values fail because they don't give the welder operational latitude inside the qualified range.

Fix: Always specify ranges for amperage, voltage, and travel speed.

4. Missing joint sketch

The WPS describes a B-U2 groove in text but has no sketch. Auditors require a visual.

Fix: Embed an Annex B joint detail or a custom sketch for every joint covered.

5. Base metal listed as "ASTM A36 or equivalent"

"Or equivalent" is not a code-acceptable substitution. Different ASTM specifications have different Group numbers in Table 6.9 and can require different fillers.

Fix: List specific specifications. If the WPS covers multiple, list each one and verify it's in the same Group.

6. Missing supporting PQR (or missing Clause 5 citation)

The WPS isn't tagged as prequalified per Clause 5, but it also has no supporting PQR reference. Auditor can't trace the qualification path.

Fix: Every WPS either cites "Prequalified per AWS D1.1:2025 Clause 5" or references a specific PQR by number.

7. Missing filler hydrogen designator on SMAW low-H

SMAW WPS specifies "E7018" but doesn't list the hydrogen designator (H4, H8, H16). For high-restraint or high-strength applications this is essential.

Fix: Always include the hydrogen designator on low-hydrogen electrodes.

8. Preheat below code minimum

WPS lists preheat at 50°F for 1-inch plate of A572-50, but Table 5.8 minimum for that material/thickness is higher.

Fix: Cross-reference Table 5.8 by material category and thickness. Rule engines flag this automatically.

9. No revision history block

The WPS shows Rev 3 in the header but has no in-document history of Revs 0–2. Auditor can't see what changed.

Fix: Maintain an in-document revision history table (Rev, Date, Author, Change, Approver).

10. Signature without credential listed

The WPS is signed "Joe Smith, QC Manager" but doesn't list Joe's CWI or PE credential number. Auditor can't verify qualification at sign time.

Fix: Always include the signer's credential type and number on the signature block.

The compounding effect

None of these mistakes are individually catastrophic. But a WPS with three of them — wrong table citation, single amperage, no joint sketch — fails on the spot. A WPS tool that runs these checks at draft time prevents the compounding.