The PP packing belt production line produced by Qingdao Zhongrui Plastic Machinery Co., Ltd. has introduced foreign technology and developed a new generation of double belt PP packing belt production line with one machine. The production line can produce ultra-thin packing belt, raw rice packing belt and environmental protection packing belt. The product patterns are neat, uniform and clear, and the weight is lighter than gram The main extruder of one machine double belt packing belt production line is made of 38 Cr Mo Al by nitriding treatment, adopting new compression ratio conforming to PP characteristics, abrupt progressive screw barrel, special hard tooth surface reducer for plastic machine, and high specification configuration to ensure extrusion effect.