Carbon steel fittings，It is the most widely used pipe product. The main materials are q235 20, 35, 45, 16mn. The main products include carbon steel elbows, carbon steel flanges, carbon steel tees, carbon steel tees, carbon steel diameter tubes (size heads), carbon steel caps (tube caps) and so on. The main implementation standards include national standards, U.S. standards, daily standards, etc., and its Chinese standards also include the Ministry of Chemical Industry standards, Sinopec pipe standards, power pipe standards. Steel pipe elbow in the pipeline system, elbow is a pipe fittings to change the direction of the pipeline. Carbon eccentric reducer It is a kind of pipe fitting used in pipe reducing. The commonly used forming process is reducing pressing, expanding pressing or reducing plus expanding pressing, and stamping can also be used for some specifications of reducing pipes.