1： Structural requirements for plastic parts:

The appearance requirements of automotive lighting fixtures are extremely high, and no material marks or gate marks are allowed on the appearance, let alone shrinkage marks, fusion marks, and burrs.

3) Plastic parts have complex shapes and require high surface smoothness. There are no inverted buckles on the inside and outside of the plastic parts, and there is no need for lateral core pulling. Plastic parts are left and right mirror parts.

This product is an electroplated part, with aluminum plating on the appearance and strict lighting requirements. The design of the draft angle on the outer surface should be reasonable.

In addition, the headlight material of the car is BMC, which belongs to thermosetting plastic. This material is a special hard material with a shrinkage rate of almost zero, and there is no need to add a shrinkage rate in injection mold design. Due to BMC being a special type of hard plastic, it has high dimensional accuracy, good processing performance, but poor fluidity.

2： Injection mold structure

The car headlights are left and right mirror parts, so the number of cavities selected is 1+1, and a cold runner pouring system is adopted. Moreover, there is no reverse buckle on the inner and outer sides of the plastic part, so there is no need to set up a lateral core pulling mechanism.

3： Injection molding process

Add BMC material to the injection molding machine barrel, generate shear heat through screw rotation, melt it at lower temperatures, and then inject the viscous material into the pre heated mold under high pressure. Under the action of high temperature, a chemical reaction is carried out, and after being kept under pressure, it solidifies and forms. The molded plastic parts are then taken out by opening the mold.