... 2,Size: From1/8" to 64" 3,Standard: BS,DIN etc Socket-welding flange Production standard: GB/T9112~9124-2000 JB/T81 ... A234 WPBTypes: Welding Neck Flanges, Slip on Flanges, Threaded Flanges, Socket Welding Flanges, Blind Flanges, Orifice Flanges, Lap Joint Flanges, Ring ... with polyethylene film steel cases or as customer’s request. Socket-welding flange