Carbon and Stainless Steel Welding Neck Flange Bores Flange bores of welding neck flanges according ASME/ANSI B16.5-1996
Pipe Flanges and Flanged Fittings - can be found in the table below:
1) Stainless steel Schedule 10S diameters are equal to Light Wall in sizes up to 12" and to Schedule 10 above