Threaded elbows (also known as threaded elbows) are fittings that change the direction of pipelines in piping systems. According to the angle, there are 45 ° and 90 °, and other abnormal angle elbows such as 60 ° are also included according to the engineering needs. The materials for threaded elbows include cast iron, stainless steel, alloy steel, malleable cast iron, carbon steel, non-ferrous metals, and plastics.