Welding P Numbers. To reduce the number of welding and brazing procedure qualifications required base metals have been assigned P-Numbers by the ASME BPVC. Different material have different P-Numbers for ex for SA 106 GR B P-Number 1 and for SA 312 TP 304 P-Number is 8.
P numbers are groupings of base metals with similar welding characteristics that have been approved for pressure boundaries when constructing pressure vessels or piping systems. PQR qualified for P-Number 1 SA 106 GRB to SA 106 GRB the welding procedure shall qualify for P-Number 1 SA 333 GR6 or SA 234 GR. P- Number Group Number and S numbers are groupings of base metals with similar weldability as defined in ASME Section IX Table QW 422 or AWS D11.
THE P NUMBER This number is used to group similar Base Metals allowing qualification of an entire selection versus qualification of just one.
THE P NUMBER This number is used to group similar Base Metals allowing qualification of an entire selection versus qualification of just one. P number is essential variable for most welding process. To reduce the number of welding and brazing procedure qualifications required base metals have been assigned P-Numbers by the ASME BPVC. These group numbers divide a P number to several group numbers for the purpose of welding procedure qualification when impact testing is a requirement by the construction code.