Do you know the 10 factors that affect the quality of injection molds? Mold manufacturing is a complex process, from design, processing, assembly, debugging and other steps to the final actual use. In the entire life cycle, the factors that affect the quality of the mold are mainly the following 10 aspects.
- Mold steel
Steel is the decisive factor in mold quality, and choosing reasonable steel is the top priority. The criteria for selecting steel are:
① Requirements for injection molding materialshttps://solidcomould.com/product/plastic-yellow-baby-chair-mould/
Different plastics should use different steels, such as requirements for high polishing, corrosion resistance, etc.;
② Price
Steel is good as long as it can be used, not the more expensive the better; considering the cost factor of the mold, the mold steel should be selected according to the mold life to avoid unnecessary waste; generally, the life of P20 material is about 300,000; 2738 material is no problem at 500,000, and H13/2344 is usually more than 800,000-1 million, which can be selected according to the situation;
③ Surface treatment
The surface treatment of the mold is also very important. Nitriding can enhance the surface hardness of steel and effectively extend the life of the mold; electroplating can effectively modify the mold steel. For some plastic parts that require high brightness and corrosion resistance, electroplating can be used to enhance and improve the performance of steel.
- Structural design
Mature mold structure not only takes into account the product material properties, shrinkage, molding temperature, elastic tensile deformation coefficient, etc., but also takes into account the cooling water channel, the speed of opening and closing the mold, etc. Reasonable mold structure can effectively extend the life of the mold and ensure the smooth production of the mold, improve efficiency, and reduce costs.
- Mold processing
The arrangement of mold process is particularly important. Reasonable process arrangement can speed up the production cycle, shorten the processing time, and effectively save costs. What’s more important is that accurate and reasonable processing can ensure the stability of the mold in the production process and extend its life.
Some processing errors will cause mold welding. No matter how good the welding is, it is a loss for the mold; in addition, poor processing may affect the mold action, reduce the mold life, and cause the mold to crack or even break during the production process.
- Standard parts
Although standard parts are not directly involved in molding, they control the operation of the entire mold. Good standard parts should be wear-resistant, hard enough, high precision, and not easy to deform.
- Collision (flying mold)
Collision relies on the experience of mold fitters. It seems to be a simple job but it is the most technically demanding job. Complex molds mainly depend on this skill. Flat molds are the simplest. As long as there is no flash on the fractal surface, it is basically ok.
Auto parts molds are very troublesome. Not only are the fractal surfaces irregular, but they often include multiple sliders and top blocks. At the same time, other problems of the mold can be improved and perfected through collision, so it is a comprehensive job.https://solidcomould.com/product-category/injection-mould/household-mould/
- Polishing/leather grain
Mold polishing is the last link in mold manufacturing. Polishing is directly reflected on the plastic parts, so this is the most face-saving job. Polishing can also help and supplement the mold action, especially for demolding. Often, some mold production is not smooth because of inadequate polishing, excessive resistance, difficulty in demolding, and even top whitening and top cracking.
- Mold assembly
Mold assembly is like assembling a machine. Every part and every screw must be correct. Otherwise, the consequences will be quite serious. At the least, it will lead to product defects and affect production. At the worst, it will completely damage the mold and cause it to be scrapped. Therefore, the assembly work must be very meticulous. During the assembly process, special attention should be paid to the cleaning of the mold, especially the water channel and screw holes. The iron filings inside must be blown clean.
- Hot runner or cold runner
This actually has the least impact on the quality of the mold, because the hot runner is generally a brand specified by the customer, especially some big customers. Foreign well-known brands are very good in both quality and after-sales service, so there is generally no problem with quality.
It’s just that the quality of some domestic hot runners varies greatly. In order to save costs and gain price advantages, some small companies use some unreliable heating and conduction accessories, which are prone to problems. The main problem of the cold runner is how to ensure the balance of injection molding, gate size, injection pressure, etc.
- Cooling water channel
Anyone who has experience with molds knows how important cooling is to a mold. Due to the increase in prices and labor wages, when mass-producing products, the profit brought by not reducing the injection cycle by one second is unimaginable.
However, while speeding up the production cycle, the mold temperature will rise. If it is not effectively controlled, the mold will be too hot to be molded, and even the mold will be deformed and scrapped. Therefore, excellent water channel design is particularly important, including the arrangement density, diameter, and mutual connection of the water channel.
- Mold maintenance
Mold maintenance is mainly maintenance and care during the production process. The mold is like a car. If it is not used for a long time and not maintained, it may cause the mold to be scrapped. Therefore, comprehensive maintenance should be carried out after each use of the mold, especially the rust prevention of the molding part and the rust prevention of the main moving parts.
Because the mold needs to be connected to water during the production process, it may be stained by water during the installation or disassembly process, so it is necessary to ensure that the mold is dry, and then apply a layer of oil for protection.
