AWS Certified Welding Inspector — FundamentalsWelding SymbolsMedium
A welding technician is interpreting a blueprint for a bridge component. The welding symbol includes a supplementary symbol in the tail, which is the letters 'PWHT'. What does this indicate to the welder?
- AProof weld has been performed.
- BPartial weld penetration is acceptable.
- CPreheat required before welding.
- DPost-weld heat treatment is mandatory.
Show answer & explanationAnswer & explanation
Correct answer: D. Post-weld heat treatment is mandatory.
The tail of the welding symbol is used for supplementary information. 'PWHT' is a common abbreviation for Post-Weld Heat Treatment, which is a critical process for certain materials and applications to relieve residual stresses or modify microstructure.
Why the other options are wrong
- A. Proof weld is not a standard abbreviation used in this context.
- B. Partial weld penetration is indicated by weld symbol configuration, not 'PWHT'.
- C. Preheat is typically indicated by a flag symbol or specific notes, not 'PWHT'.
Tail of Welding Symbol
The tail of the welding symbol is an optional addition used to convey supplementary information, often including specifications, processes, or other references.
- Located at the end of the reference line, opposite the arrow.
- Used for specific instructions, codes, or processes.
- Can contain abbreviations like 'PWHT', 'WPQ', 'NDE' codes etc.
Memory trick: Tail's Tale Tells Extra Details.