Pipe extrusion production lines are divided into three categories: the first category is HDPE pipe extrusion production lines, and HDPE pipes are divided into gas pipes and water supply pipes. The diameter specifications of the gas pipeline are: 20mm -630mm, and the pressure levels are: SDR9, SDR11, and SDR12.5. The diameter specifications of the water supply pipeline are: 20mm -2000mm, and the pressure levels are: SDR9, SDR11, SDR12.5, SDR17, SDR21, SDR26, SDR33, SDR41. The second category is PPR pipe extrusion line, PPR pipe is divided into hot water pipe and cold water pipe. The diameter specifications are: 20mm -160mm, and the pressure levels are: S2.5, S3.2, S4.0. The third category is PVC-U pipe extrusion line. PVC-U pipe is divided into drainage channel and water supply pipe. The diameter specifications of the drainage pipe are: 50mm -400mm, and the pressure ratings are: SDR21, SDR26, and SDR33. The diameter specifications of the water supply pipeline are: 20mm -1200mm, and the pressure levels are: SDR9, SDR11, SDR12.5, SDR17, SDR21, SDR26, SDR33.