Design of gating system for plastic injection mold. The gating system refers to the channel through which the plastic melt flows in the plastic injection mold after being ejected from the nozzle of the injection machine before reaching the mold cavity. The gating system is divided into two categories: the gating system of cold runner and the gating system of hot runner. The design of pouring system is a very important part of plastic injection mold design. It has a direct impact on the molding efficiency of plastic parts with good performance and ideal appearance. It is a technical problem that plastic injection mold designers must pay great attention to.
1.The composition and function of the gating system of cold runner.
The general flow channel gating system is generally composed of four parts: main flow channel, split channel, gate and cold material hole. A gating system for a plastic injection mold mounted on a vertical or horizontal injection machine with a main channel perpendicular to the parting surface of the injection mold.
the functions of the ordinary flow channel gating system are as follows: the plastic melt from the injector nozzle is evenly and smoothly transported to the cavity, and the injection pressure is effectively transferred to all parts of the cavity during the filling and solidification of the plastic melt, so as to obtain plastic parts with complete shape and good quality inside and outside.
2.The design of gating system for the injection mold
Gating system design is reasonable not only for the performance, structure, size and different quality, but also with the using rate of plastic materials and molding production efficiency and so on, so the gating system design is an important part of the injection mold design, overall design of gating system, the general should follow
1)Understand the molding properties of plastic and the flow characteristics of plastic melt
2)Use as short a process as possible to minimize heat and pressure loss
3)The gating system design should be conducive to good exhaust
4)Prevent core deformation and insert displacement
5)It is convenient to trim the gate to ensure the appearance quality of plastic parts
6)The gating system should be combined with the cavity layout
7)Checking the flow distance ratio and flow area ratio