... .Material :SS400,A105 ,Q235 etc. 3.Size:DN15-DN2000 Carbon ANSI Flanges 1. Standard ANSI,ASTM,JIS,DIN,GB etc ... 3. Size 1/2-78 inch (DN15-DN2000)4. Material Carbon Steel Material: A105, SS400, SF440 RST37.2,S235JRG2,P250GH,C22 ... heat exchanger, shipbuilding, construction, etc.6. Production processraw material--cutting--heating--forging--heat treatment--marching--inspection.7. Inspection factory in-house ...