The problem of guiding and positioning is the repeated dislocation action when the injection mold is opened and closed. When the mold is closed, the guide pin and the guide bush are first guided to ensure that the mold parts have the correct initial motion trajectory. After the positioning is over, the positioning comes into play. Due to the different structures of injection mold parts, each plastic part will generate more or less lateral forces during injection molding. Lateral forces are greatest for deep cavities and asymmetrical parts. There is a gap between the guide post and the guide sleeve, and its working state is actually in line contact. Therefore, in the injection mold, the guide post and the guide sleeve alone cannot withstand the huge lateral force during injection molding.

The positioning system must be designed to withstand lateral forces. The injection mold structure that ensures that the moving parts move according to the established trajectory is called the guiding system; the structure that guarantees the relative positional accuracy between the front and rear molds and the movable parts is called the positioning system.

The positioning of the mold base positioning block is usually called secondary positioning. Secondary positioning is the precise positioning of the front and rear mold bases. The positioning accuracy of the zero-degree positioning block is much higher than that of the guide post and guide sleeve. The matching groove of the positioning block on the mold base should be processed in the mold base factory as much as possible to ensure the matching accuracy of the front and rear mold bases. The material of the positioning block is heat-treated alloy steel or copper and graphite materials, and the friction surface of the positioning block should have a lubricating oil groove. The zero-degree positioning block has two functions guiding and positioning, which can effectively protect the weak penetration surface on the mold core. The mold base positioning block is very important for precision molds. The matching height on both sides of the zero-degree positioning block determines the length of the positioning effect. After designing the zero-degree positioning block, the movable mold and the fixed mold have a certain distance of precise guiding and positioning before the mold is closed. Therefore, in a mold with many insertion positions, the zero-degree positioning block can effectively protect the insertion position from damage.

Taizhou Huangyan Jinhong Plastic Mould Parts Co., Ltd. is an injection mold manufacturer from China, its own plastic mold factory specializes in the production of plastic compression springs