Is there a code-required WPS numbering scheme?

No. AWS D1.1 requires that each WPS have a unique identifier, but doesn't specify the format. Most shops use a year + sequential number scheme. Some add process or material codes.

Can I renumber my existing library?

Yes, but it's risky — every drawing, weld map, and production record that references a WPS by number will need updating too. Most shops keep legacy numbers and apply a new scheme only to new WPSs.

What's wrong with naming WPSs descriptively?

Descriptive names (like 'SMAW-A36-1G-12FT') seem convenient but break when procedures span multiple processes or materials, and they're hard to reference in production paperwork. Short numeric IDs are more practical.

WPS numbering scheme: best practices for a growing library

A consistent WPS numbering scheme saves hours during audits and onboarding. Here's the format most certified shops use — and the formats that cause problems.

A consistent WPS numbering scheme is one of those decisions that seems trivial when you make it but pays back enormously over the next 10 years. Shops with clean schemes onboard new CWIs faster, run audits cleaner, and respond to AHJ requests more quickly. Shops with inconsistent schemes lose hours every audit.

What a numbering scheme has to do

A good WPS numbering scheme:

Uniquely identifies each WPS across the entire library
Survives revision history (the number doesn't change when revision changes)
Is short enough to write on drawings and weld maps
Doesn't encode information that changes (don't put the welder's name in the number)
Sorts well when the library is viewed as a list
Doesn't collide with the supporting PQR's numbering scheme

A bad numbering scheme fails at one or more of these.

The most common scheme that works

The year + sequential format:

WPS-{YY}-{NNN}

Where YY is the last two digits of the year of initial release and NNN is sequential within that year. Examples: WPS-25-001, WPS-25-002, WPS-26-001.

This scheme:

Is short and writable
Sorts chronologically
Encodes initial-release year (useful for context)
Continues sequentially within a year as new WPSs are written

A 30-WPS library issued over 2-3 years looks like:

WPS-24-001 through WPS-24-018
WPS-25-001 through WPS-25-012

Reading the list, you immediately see the library's release history.

Variants and tradeoffs

Add a process suffix: WPS-25-001-SMAW. Useful for very large libraries. Adds length; increases chance of inconsistency.

Add a project prefix: PROJ-NAME-WPS-25-001. Useful when WPSs are project-specific. Painful when WPSs span projects.

Pure sequential without year: WPS-001, WPS-002. Simple but loses chronological context after a few years.

Date-based: WPS-2025-05-08-001. Precise but verbose. Hard to write on weld maps.

Pick one scheme. Apply it consistently across the library. Don't mix schemes.

What NOT to encode

Information that changes over time should NOT be in the WPS number:

Welder name (welders come and go)
Project name (WPS often spans projects)
Customer name (same)
CWI name (signers change)
Revision number (already separate)

These belong in the WPS content, not the identifier.

Revision number stays separate

A common confusion: rolling the revision number into the WPS ID itself. "WPS-25-001-Rev3" as the WPS identifier.

This breaks when:

Drawings reference WPS-25-001 (no revision suffix)
Weld maps reference WPS-25-001
The supporting PQR cites WPS-25-001 as the procedure under qualification

The WPS number is the identifier. The revision number is metadata that changes with each edit. Keep them separate:

WPS number: WPS-25-001 (stable for the life of the procedure)
Revision: 0, 1, 2, 3... (changes with each edit)
Filename: WPS-25-001-rev-3.pdf (the filename is OK to combine)

Coordinating with PQR numbering

PQRs need their own numbering scheme, separate from WPSs. A common pattern:

PQR-{YY}-{NNN}

Same format as WPS but with the PQR prefix. PQRs and WPSs sequence independently.

So:

WPS-25-007 might be supported by PQR-23-002
PQR-25-001 might support WPSs WPS-25-009, WPS-25-014, WPS-26-003

The supporting PQR number is cited in the WPS header. The list of WPSs supported by a given PQR can be cross-tracked in a separate register.

Handling renumbering

The cardinal rule: don't renumber the existing library. Every change touches drawings, weld maps, production records, audit-trail documents, and welder qualification records.

If your current scheme is broken (inconsistent, descriptive, encoded with changing info):

Freeze the existing scheme — don't issue new WPSs with the old format
Apply the new scheme to new WPSs only
Cross-reference table maintained for legacy WPSs
Phase out legacy WPSs naturally as they expire / are replaced

A 2-3 year transition is typical. By the end, the library is on the clean scheme without disrupting active project work.

What to write on drawings and weld maps

Production paperwork should reference WPSs by number, not by description:

✅ "Weld per WPS-25-001 Rev 2"
❌ "Weld per SMAW procedure on A36"

The number is unambiguous. The description is interpretation.

For drawings showing multiple welds with multiple procedures, a WPS schedule on the drawing is common:

Weld schedule:
  W1: per WPS-25-001 Rev 2
  W2: per WPS-25-001 Rev 2
  W3: per WPS-25-007 Rev 1
  W4: per WPS-25-014 Rev 0

Numbers map to weld marks on the drawing.

The audit-day benefit

A clean numbering scheme dramatically speeds audit response. The auditor picks weld W3 from the drawing → references WPS-25-007 → pulls Rev 1 from the library → cross-references the supporting PQR → done.

A messy scheme adds 5-10 minutes per weld traced. Across a multi-day audit hitting dozens of welds, that's hours of unnecessary friction. A clean scheme costs nothing to set up at the start; a messy scheme costs decades to fix.