api 5000Refer API 6a 6b And 6bx Flanges Weht Chart According to ASME B16.5 And (American Petroleum Institute) API 6A 5000 Flange Dimensions. Api 6a Flange Material Specification.5000# API Socket Weld Flange is made up of A105 carbon steel and has a minimum yield strength of 45000. API 10000 Flange is manufactured from hh steel alloy after heat treatment