Carbon steel pipe elbow is to change the direction of the metal pipe fittings. Connections are threaded and welded. (My company mainly produces carbon steel elbow pipe welding class) carbon steel elbow first by its radius of curvature to points, can be divided into long radius elbows and short radius elbows. Long radius elbow refers to its radius of curvature is equal to 1.5 times the pipe diameter, i.e. R = 1.5D. Short radius elbow refers to its radius of curvature equal to the pipe diameter, ie R = 1.0D. (D is the bend diameter, R is the radius of curvature) when pressing force rating points, about seventeen kinds, and U.S. standard pipes are the same, there are: Sch5s, Sch10s, Sch10, Sch20, Sch30, Sch40s, STD, Sch40, Sch60, Sch80s, XS; Sch80, Sch100, Sch120, Sch140, Sch160, XXS, which is the most common STD and XS two kinds. According to the angle of bend points, 45 ° elbow, there are 90 ° and 180 ° elbow bend. Implementation of standards GB / T12459-2005, GB / T13401-2005, GB / T10752-1995, HG / T21635-1987, D-GD0219 and so on. Carbon steel can be divided into 10 # 20 # A3 Q235A 20g Q345B 20G 16Mn ASTM A234 ASTM A105 ASTM A403 and other raw materials used for the production of these materials can be called carbon steel elbow by elbow angle points:. 45 °, 90 °, 180 ° three common elbow, and another project needs, you can customize as 60 ° and so special. And carbon steel pipe are linked: weld, flanged, threaded, socket connections form. Process can be divided according to the form: welding elbow, pressing elbow, casting elbow. Uses: connecting two tubes, the tube can be at a right angle, 45 ° or 180 ° direction. Manufacturing standards: GB, American standard, Japanese standard, German standard, the Russian standard. The basic process of carbon steel elbow is: First welding a polygonal cross-section polygonal ring or both ends of the shell closed polygonal fan shell, washed over the internal pressure of the media, applying less pressure, under pressure, including the role of the cross-sectional by polygon becoming round, eventually becoming a circular ring shells. If necessary, a circular ring shell can be cut four or six 90 ° elbows 60 ° elbows or other specifications of the elbow, the elbow in the process for the manufacture of any ratio greater than 1.5 times the diameter of the inner diameter and elbow specifications large elbow, is an ideal method for the manufacture of large carbon steel elbow. The advantage of the carbon steel elbow production process mainly in the following aspects: (1) without the tube as raw materials, saving pipe equipment and tooling costs, and get arbitrarily large diameter and wall thickness of the relatively thin carbon steel elbows. (2) blank or developable surface is flat, so simple cutting, easy to ensure accuracy, easy assembly and welding. (3) Due to the above two reasons, you can shorten the manufacturing cycle, the production cost is greatly reduced. Because does not require any special equipment, especially for on-site processing of large carbon steel elbow. (4) steel elbow pipe system is suitable for oil, gas, chemicals, utilities, construction and boiler industry.