... 2"-40" 5. Type:Slip on flanges,Plate flanges, Blind flanges, Spectacle flanges,Lap joint ... 64 and 160,5K-40K and so on . 7. Sealing surface : FF ,RF, LJ, FM ... for : petroleum,chemical,power,gas,water,linepipe, heat exchanger,shipbuilding,construction,etc. 9. Tolerance:not less than ... Production process : raw material--cutting--heating--forging--heat treatment--maching--inspection. 11. Mill ceitificate :3 ...