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.API Specification 6A covers wellhead and tree equipment as follows: API Specification 6A Wellhead Equipment Valves, Chokes, and Actuators Plugs, Connectors, and Gaskets Other