Ten factors that affect the quality of the mold!

The mold manufacturing process is a complex process, from the steps of design, processing, assembly, debugging, etc., and finally it can be put into use. In the whole life cycle, the factors affecting the quality of the mold mainly include the following ten aspects:

1. Die steel

Steel is the decisive factor for the quality of the mold, and choosing a reasonable steel is the top priority. The criteria for selecting steel are:

① Requirements for injection molding materials - different plastics should use different steels, such as high polishing requirements, corrosion resistance requirements, etc.;

②Price - the quality of the steel is good, not the more expensive the better; considering the cost of the mold, the mold steel should be made of materials corresponding to the life of the mold to avoid unnecessary waste; generally, the life of P20 is about 300,000; 2738 , 500,000 is no problem, H13/2344 is usually more than 80-1 million, you can choose according to the situation;

③ heat treatment. The surface treatment of the mold is also very important. Nitriding - can enhance the surface hardness of steel and effectively prolong the life of the mold; electroplating - can effectively modify the mold steel, and for some plastic parts that require high brightness and corrosion resistance, electroplating can be used to enhance and improve the performance of the steel

2. Structural design

The mature mold structure not only takes into account the material properties of the product - shrinkage rate, molding temperature, elastic tensile deformation coefficient, etc., but also takes into account the cooling water path, the speed of opening and closing the mold, etc. Reasonable mold structure can effectively prolong the life of the mold and ensure the smooth production of the mold. Improve efficiency and reduce costs.

3. Mold processing

If a worker wants to do a good job, he must first sharpen his tools. The arrangement of the mold process is particularly important. A reasonable process arrangement can speed up the production cycle, shorten the processing time, and effectively save costs. And more importantly, accurate and reasonable processing can ensure the stability and prolong the life of the mold in the production process. Some machining errors will lead to mold welding, no matter how good the welding is, it is a loss to the mold; in addition, poor processing may affect the mold action, reduce the life of the mold, and cause the mold to crack during the production process. even broken.

4. Standard parts

It is the lowest piece of wood that determines the capacity of the bucket. Everyone understands this principle, but it is often not noticed when doing it. The same is true for the mold. Although the standard part does not directly participate in the molding, it controls the operation of the entire mold. Good standard parts should be able to wear, hard enough, high precision, and should not be deformed. The price difference of standard parts of different brands is very large, so don't blindly bargain for molds, and your molds will go from Mercedes-Benz to the public.

5. Touch (flying mold)

It relies on the experience of the mold fitter, and the seemingly simple work is the most technical work. The complex mold mainly depends on this skill. The flat mold is the simplest, and the fractal surface is basically ok as long as there is no flash break. For example, auto parts molds are very troublesome, not only the fractal surface is relatively irregular, but also often includes multiple sliders and top blocks. At the same time, other problems of the mold can be improved and perfected by the touch. So it is a comprehensive work.

6. Polished/Skin grain

The polishing of the mold is the last link in the manufacture of the mold. Polishing is directly reflected on the plastic parts, so this is the most honorable job. Polishing can also help and supplement the mold action, especially for demolding. Often, some molds are not produced smoothly because the lighting is not in place, the resistance is too large, the mold release is difficult, and even the top is white and the top is cracked.

7. Mold assembly

Mold assembly is just like assembling a machine. Every part and every screw can't be wrong, otherwise the consequences will be quite serious, ranging from product defects and affecting production, to complete damage to the mold and scrapping. Therefore, the assembly work must be very meticulous. During the assembly process, pay special attention to the cleaning of the mold, especially the waterway and screw holes. Be sure to blow off the iron filings inside, otherwise the customer will be very angry.

8. Hot runner or cold runner

In fact, this has the least impact on the quality of the mold, because the hot runners are generally designated by customers, especially some large customers. Foreign well-known brands are very good in terms of quality and after-sales service, so there is generally no problem in quality. It's just that the quality of some domestic hot runners varies greatly. In order to save costs, individual small businesses strive for price advantages and use some unreliable heating and conduction accessories, which are prone to problems. The main problem of cold runner is how to ensure the balance of injection molding, gate size, injection pressure and so on.

9. Cooling water circuit

Anyone with mold experience knows how important cooling is to a mold. Due to the increase in prices and labor wages, when mass-producing products, the profits brought by not reducing the injection cycle by one second are unimaginable. However, when the production cycle is accelerated, the temperature of the mold will rise. If it is not effectively controlled, the mold will be too hot to be formed, and even lead to the failure of the mold to be deformed and scrapped. Therefore, good waterway design is particularly important, including the arrangement density, diameter, and links between waterways and so on.

10. Mold maintenance

Mold maintenance is mainly maintenance and maintenance in the production process. The mold is like a car. If it is not used for a long time without maintenance, it may cause the mold to be scrapped. Therefore, a comprehensive maintenance should be carried out every time the mold is used, especially the rust prevention of the molding part and the rust prevention of the main moving parts. Because the mold needs to receive water during the production process, it may fall on the mold during the installation or disassembly process, so it is necessary to ensure that the mold is dry, and then apply a layer of oil to protect it.