Carbon steel elbows are metal fittings that change the direction of pipelines on carbon steel pipes. The connection methods are threaded and welded. According to the angle, there are three kinds of 45 ° and 90 ° and 180 ° most commonly used. In addition, according to the needs of the project, it also includes other abnormal elbows such as 60 °. Elbow materials are cast iron, stainless steel, alloy steel, malleable cast iron, carbon steel, non-ferrous metals and plastics. The connection methods with the pipe are: direct welding (the most common method) flange connection, thermal fusion connection, electric fusion connection, screw connection and socket connection. According to the production process, it can be divided into: welding elbow, stamping elbow, push elbow, casting elbow and so on. Other names: 90-degree elbow, right-angle bend, love and bend.