... pipes, oil pipes, ERW pipes, seamless steel pipes,elbow,reducer,tee,caps,flange,tube etc.. 1) Stainless steel flange and carbon steel flange2) Standard: ASME, ANSI, API, JIS ... as follows:steel pipes and pipe fittings, such as saw pipes, oil pipes, ERW pipes, seamless steel pipes,elbow,reducer,tee,caps,flange,tube etc ...