Automobile mold classification and manufacturing process

In a broad sense, “automobile mold” is a general term for the molds that make all parts of the car. Such as injection molds, stamping molds, forging molds, casting wax molds, glass molds, etc. When people say a car, the first thing that comes to mind is the body of the car. That is to say, the body is the identifying assembly of the car. The body represents the image character of that car. In a narrow sense, an automobile die is a general term for the die for punching all stamping parts on an automobile body. That is, “auto body stamping die”. For example, top cover flanging die, beam reinforcement plate pressing die, etc.

1. Classification of automotive plastic molds
There are many ways to classify automobile plastic molds, which can be divided into the following categories according to the different methods of forming and processing plastic parts:

·Injection mold
Injection mold is also called injection mold. The molding process of this mold is characterized by placing the plastic material in the heating barrel of the injection machine. The plastic is heated and melted, and driven by the screw or plunger of the injection machine, it enters the mold cavity through the pouring system of the nozzle and the mold. Since the heating and pressing device can function in stages, injection molding can not only mold plastic parts with complex shapes, but also has high production efficiency and good quality. Therefore, injection molding occupies a large proportion in the molding of plastic parts, and injection molds account for more than half of plastic molding molds. Injection machines are mainly used for the molding of thermoplastics, and in recent years, they have also been gradually used for the molding of thermosetting plastics.

·Compression mold
Compression molds are also known as compression molds or compression molds. The molding process of this kind of mold is characterized in that the plastic raw material is directly added into the open mold cavity, and then the mold is closed. After the plastic is in a molten state under the action of heat and pressure, the cavity is filled with a certain pressure. At this time, the molecular structure of the plastic produces a chemical cross-linking reaction, which gradually hardens and sets. Compression molds are mostly used for thermosetting plastics, and their molded plastic parts are mostly used for the shells of electrical switches and daily necessities.

·Transfer mode
Transfer mold is also known as injection molding or extrusion mold. The molding process of this mold is characterized by adding plastic raw materials into the preheated feeding chamber, and then applying pressure to the plastic raw materials in the feeding chamber by the pressure column. The plastic is melted under high temperature and high pressure and enters the cavity through the casting system of the mold, and then The chemical cross-linking reaction occurs and gradually solidifies into shape. The transfer molding process is mostly used for thermosetting plastics, which can mold plastic parts with complex shapes.

·Extrusion die
Extrusion die is also called extruder head. This mold can continuously produce plastics with the same cross-sectional shape, such as plastic pipes, rods, sheets, etc. The heating and pressurizing device of the extruder is the same as that of the injection machine. The molten plastic passes through the machine head to form a continuous molding plastic part, and the production efficiency is particularly high.

In addition to the types of plastic molds listed above, there are vacuum forming molds, compressed air molds, blow molding molds, low-foaming plastic molds, and the like.

The stamping parts on the automobile body are generally divided into cover parts, beam parts and general stamping parts. Stamping parts that can clearly express the characteristics of the car’s image are car covers. Therefore, the more specific automobile mold can be said to be “car panel stamping mold”. Referred to as automobile cover die. For example, front door outer panel trimming die, front door inner panel punching die, etc.

2. Classification of automobile stamping dies
Of course, there are not only stampings on the body of the car. The dies for all stamping parts on automobiles are called “automotive stamping dies”. It can be summed up as:
1. Auto mold is a general term for molds that manufacture all parts of an automobile.
2. Automobile stamping die is a die for punching all stamping parts on automobiles.
3. The automobile body stamping die is a die for punching all stamping parts on the automobile body.
4. The automobile cover stamping die is a die for punching all the cover parts on the automobile body.

car tire mould
Molds for vulcanizing and molding various types of tires.

3. Classification of automobile tire molds
1. Active mold consists of pattern ring, mold sleeve, upper and lower side plates.
The movable mold distinguishes the conical surface guided movable mold and the inclined plane guided movable mold
2. The two halves of the mold are composed of an upper mold and a lower mold.

4. High-speed machining technology for automobile molds
High-speed machining technology has been widely used in the domestic and foreign automotive mold manufacturing industry, and has achieved great benefits, but the mechanism and related theories of high-speed machining are still incomplete, and the high-speed machining database for automotive molds has not yet been established. Domestic and foreign companies still use the traditional “trial cutting method” and “experience method” to select high-speed cutting tool parameters and high-speed cutting processing parameters. When processing a new material, it is often necessary to use multiple tools for repeated cutting tests. , to study and analyze the wear and damage methods of tools and their causes, and find out a set of optimal tool materials and processing parameters. This is repeated many times, which is blind and wastes a lot of manpower, financial resources and resources. For high-speed machining of special materials such as alloy cast iron, high-strength alloy steel, super alloys (such as titanium alloys), etc., how to select suitable cutting tools according to material characteristics and how to design reasonable cutting parameters are still being researched and developed. middle.

High-speed machining technology is an advanced manufacturing technology in the 21st century, with strong vitality and broad application prospects. Through high-speed cutting technology, a series of problems plagued by conventional cutting of automobile molds can be solved. In recent years, high-speed cutting technology has been widely used in most mold companies in the United States, Germany, Japan and other industrialized countries, and about 85% of mold EDM processes have been replaced by high-speed machining. High-speed machining technology combines high efficiency, high quality and low consumption, and has become the mainstream in the international mold manufacturing process.

Through the practical application of high-speed cutting technology in the automotive mold manufacturing industry at home and abroad, high-speed cutting technology has the following advantages:
1. High-speed machining increases the processing speed
High-speed cutting is used for high-speed cutting of automobile molds at a cutting speed about 10 times higher than that of conventional cutting. Since the excitation frequency of the high-speed machine tool spindle far exceeds the natural frequency range of the “machine tool-tool-workpiece” system, the machining process of automobile molds is smooth and shock-free.
2. High-speed machining has high production efficiency
Machining the mold with a high-speed machining center or a high-speed milling machine can complete the roughing and finishing of the profile and the machining of other parts of the automobile mold in one clamping of the workpiece, which is the so-called “One Pass Machining” technology. The application of high-speed cutting technology has greatly improved the development speed of automobile molds.
3. High-speed machining can obtain high-quality machined surfaces
Due to the extremely small step size and depth of cut, high-speed machining can achieve high surface quality, even eliminating the need for bench trimming.
4. Simplify the machining process
Conventional milling can only be carried out before quenching, and the deformation caused by quenching must be trimmed by hand or finished by electrical machining. This can now be done by high-speed machining without the surface hardening caused by electrical machining. In addition, due to the reduced cutting amount, high-speed machining can use smaller diameter tools to process smaller corner radii and mold details, saving part of the machining or manual trimming process, thereby shortening the production cycle.
5. High-speed machining makes the repair process of automobile molds more convenient
Automobile molds often need to be repaired many times during use to prolong their service life. If high-speed cutting is used, the work can be completed faster, and the processing effect of milling instead of grinding can be achieved, and the original NC program can be used without reprogramming. And can be accurate.
6. High-speed machining can process hard automobile molds with complex shapes
It can be seen from the high-speed cutting mechanism: during high-speed cutting, the cutting force is greatly reduced, and the cutting process becomes easier. High-speed cutting has great advantages in cutting high-strength and high-hardness materials, and can process complex profiles and high hardness. car mold.

Scroll to Top