ASME Section IX tables (QW-252 through QW-256) list essential variables for each major process:
| Variable | Symbol | Change Requires Requal? | |----------|--------|--------------------------| | F-number | QW-404.12 | YES | | A-number | QW-404.5 | YES | | Thickness (T) | QW-403.6 | YES | | Preheat (reduction) | QW-406.1 | YES | | PWHT (adding/removing) | QW-407.1 | YES | | Electrode diameter (beyond range) | QW-404.13 | YES | | Amperage (minor change) | – | NO | welding standard asme
Does the PQR cover the base metal thickness and filler metal type (P-Numbers and F-Numbers) required for the job? ASME Section IX tables (QW-252 through QW-256) list
While Section IX tells you how to qualify, other ASME codes tell you when and where to apply those rules: welding standard asme
