api 5000API 5000 Flange Dimensions Industries and Applications Widely used in the industries. Pumps, Valves, and vessels in manufacturing and food processing. PipeApi 6a Wn Flanges applications including pressure classes – 720 psi and 960 psi, the API specified no changes to the ASA B16.5 Standard, using the 300 lb. and 400 lb. flanges