ASME
ASME Section II Part C
Specifications for Welding Rods, Electrodes and Filler Metals
The filler metal specifications that a WPS points at, and the source of the A-number and F-number groupings Section IX uses to decide what a procedure qualification covers. Also where the storage and baking requirements for low-hydrogen electrodes come from, which is the part that matters on a humid site.
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