api 5000PO BOX 639 • Bakersfield, CA 93302 855-535-1555 phone • sales@ API FLANGE BOLT & RING CHART API Pressure Rating Flange Size & Bore5000# 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