Eccentric reducer is a kind of pipe fitting used at the pipe diameter changing position. The commonly used forming process is reducing pressing, expanding pressing or reducing plus expanding pressing. For some sizes of reducing pipe, stamping can also be used. In addition to using steel pipe as raw material, eccentric reducer can also be produced by stamping process with steel plate. The shape of the die used for drawing is designed according to the inner surface dimension of the reducing pipe, and the blanking steel plate is formed by stamping and drawing.