standard welding neck flange plate, threaded, slip-on, socket welding, lap joint, blind, welding neck etc. standard welding neck flange MaterialCarbon steel:ASTM A105,ASTM A350 LF1,LF2,CL1/CL2,A234,Q235A,A106B Stainless steel:ASTM A182 F304/304L,F316/316L,StandardEN, DIN, UNI, BS, NF, ANSI, JIS, KS, API, MSS DIN:DIN2527,DIN2566, DIN2573, DIN2576, DIN2641, DIN2642, DIN2655, DIN2656, DIN2627, ...