How to make a car bumper mold?

The car bumper is a safety device that absorbs and relieves external impact and protects the front and rear of the body. It is generally composed of three parts: plastic bumper, cushioning material and beam. Plastic bumpers are strong, rigid and decorative. From a safety point of view, they can act as a buffer when a car crashes and protect the front and rear body of the car; from the appearance point of view, it can be naturally integrated with the body of the car to form a complete one body, with good decoration.

Design of bumper mold

The bumper mold adopts a monolock design, the size is large, the processing and assembly are difficult, and the mold strength needs to be good. Therefore, the fixed mold uses 718H with a pre-hardness of 30-35HRC, and the movable mold uses P20 with a hardness of 30-33HRC.

When modelling the design of auto mold, details such as manufacturability and reliability of parts must be carefully considered in advance. The local protrusion of the parts and the large cantilever structure easily lead to deformation of the parts after assembly, so it should be avoided when designing. The following methods can be used to solve the problem: one is to connect the two installation points into a whole, the other is to widen the flange, and the third is to reinforce the back. For the boundary that is compatible with the vehicle body, the method of adding flanges can minimize the deformation of the parts, which is beneficial to the improvement of the matching accuracy, and thus insured the quality of the entire vehicle.

In the process of part cooling, uneven solidification or cooling speed will cause uneven shrinkage, which will then generate stress inside the part, leading to warpage deformation and sink marks. In order to avoid these defects, the bumper must have a uniform thickness. When designing, using enough thickness change transition zone can achieve the purpose of avoiding the influence of thickness change on the surface quality of parts.

The demolding angle should be bigger than zero. Under the condition of bigger than zero, the difficulty of part demolding is proportional to the size of the demolding angle. However, the demolding angle is not as large as possible. A large angle can easily lead to uneven thickness of parts and reduce manufacturing accuracy.

The auto mold adopting internal parting design. Compared with the outer parting design, the internal parting design has a more complex mold structure, higher mold strength, and higher strength, toughness and impact resistance of the formed product. The internally divided bumper molds and molded products produced can not only reduce the injury of drivers and passengers during high-speed impact but also have the ability to protect pedestrians under ordinary conditions.

Jnmould has a complete automobile quality management system ISO/TS16949, high-precision processing equipment and testing equipment. For many years, Jnmould has provided automobile bumper mold for Peugeot, Leylo, Benz, and TOYOTA. We pay attention to the processing size of the automobile bumper mold and the matching relationship with the bumper assembly. Our design department will analyze the product's warping deformation, material flow and mold cooling cycle in detail. The mold will use The 5-axis high-precision CNC machining equipment is completed, and the processing process and parts of the car bumper mold are strictly controlled.