In the pipeline system, the Large OD elbow is a pipe fitting that changes the direction of the pipeline. According to the angle, there are three most commonly used ones: 45° and 90°180°. In addition, according to engineering needs, it also includes other abnormal angle elbows such as 60°. The elbow materials are cast iron, stainless steel, alloy steel, malleable cast iron, carbon steel, non-ferrous metals and plastics. The ways to connect with the pipe are: direct welding (the most common way) flange connection, hot melt connection, electrofusion connection, threaded connection and socket connection. According to the production process, it can be divided into: welding elbow, stamping elbow, push elbow, casting elbow, butt welding elbow, etc. Other names: 90 degree elbow, right angle bend, etc.