The ASME B36.10 and B36.19
seamless pipe specifications cover the dimensions and weights of seamless pipes for the petrochemical industry (the specs apply to welded pipes too):
The ASME B36.10 specification covers carbon and low-alloy seamless pipes sizes (dimensions and weights) between 1/8 and 24 inches
The ASME B36.19 specification, instead, covers the dimensions and weights of stainless steel, duplex, nickel-alloy seamless pipes.
Commercial seamless pipes are designated with a nominal pipe size (representing the approximate fluid conveyance capacity of the pipe) and with a “schedule”, which refers to the thickness of the pipe (the most common are schedule 40, STD, XS, XXS for carbon/alloy pipes, and 10S, 40S and 80S for stainless and nickel alloy pipes).
