According to the structure of plastic parts, the mould is designed as a three-plate type using a point gate, and the gate is set at the center of the top of the plastic part. The point gate can significantly increase the shear rate of the melt, so that the viscosity of the melt is greatly reduced, which is beneficial to mould filling. This is especially effective for PEs that are sensitive to shear rate. And the plastic parts as a packaging container, the appearance of high quality requirements, the small traces of the residue at the gate, can ensure the surface quality of the plastic parts, the mould at the gate automatically pull off, easy to realize the automation of the product production process, improve production efficiency Increased economic efficiency. The non-equilibrium gating system has a compact array of cavities, which reduces the size of the mould. To enable each cavity to be filled at the same time and evenly, the BGV (Balanced Gat Value) method is used to manually modify the size of each cavity gate to achieve balance. Use cold spots to store forward cold.