The main seamless carbon steel welding fittings of CANGZHOU YICHENG STEEL PIPE MANUFACTURE CO., LTD are as followings: Elbows including 90 elbows, 45 elbows and 180 returns and long radius or short radius, Reducers including concentric reducers, eccentric reducers, Tees including straight tees, reducing tees and Caps, supplied by us are produced from seamless steel tubing and furnished in accordance with ASTM Standards A234. The dimension, beveled ends and tolerances are according to ANSI B16.9 "Wrought Steel Butt welding Fittings", and the short radius elbows' dimension, beveled ends and tolerances are according to ANSI B16.28."Wrought Steel Butt welding Short Radius Elbows and Returns". The Pipe Fittings are used for petroleum industry, such as, petroleum and chemical refineries, oil fields, power stations, ship building, etc.