Flange cover, also known as blind flange, is a flange with no holes in the middle for sealing pipe plugs. The function is the same as that of the welded head and the screw cap, except that the blind flange and the he cap can be removed at any time, while the welded head can not. There are many types of sealing surface, such as plane, convex, concave and convex, tenon and groove surface, and ring connection surface. Flange cover sealing surface Plane (FF), protruding (RF), concave and convex (MFM), tenon and groove (TG), ring connection (RJ) Flange cover production materials Carbon Steel :ASTM A105,20#, Q235, 16Mn, ASTM A350 LF1, LF2 CL1/CL2, LF3 CL1/CL2, ASTM A694 F42, F46, F48, F50, F52, F56, F60, F65, F70; Stainess Steel: ASTM A182 F304ã304Lã F316ã316Lã1Cr18Ni9Tiã0Cr18Ni9Tiã321ã18-8ï¼ Alloy Steel: ASTM A182 F1ã F5aã F9ã F11ã F12ã F22ãF91ãA182F12ãA182F11ã16MnRãCr5Moã12Cr1MoVã15CrMoã12Cr2Mo1ãA335P22ã St45.8/â ¢ï¼ Main functions of stainless steel blind flange: 1. Connect pipe maintain pipeing performance; 2. Easy to replace a section of pipeEasy to disassemble and inspect pipe Facilitate the closure of a section of pipeinless steel flange, in order to improve corrosion resistance and weldability and appropriate amount of stability Mo, etc., welding better than chromium stainless steel flange.Use the same type of chromium stainless steel flange welding electrode (G302, G307), should be more than 200â preheating and about 800â temper after welding.If the welding parts can not be heat treatment, should choose stainless steel flange welding rod (A107, A207).