Publisher: Administrator Date: 2023-11-02
Mold manufacturing is a complex process that involves steps such as design, processing, assembly, debugging, and ultimately putting it into use. Throughout the entire lifecycle, there are 10 fundamental factors that pose a threat to the quality of plastic molds! There are 10 aspects.
1. Mold steel
Steel is the decisive factor in the quality of molds, and choosing a reasonable steel is of utmost importance. The criteria for selecting steel are:
① Different plastics with different requirements for injection molding materials should use different steel materials, such as high polishing requirements, corrosion resistance requirements, etc;
② The price of steel is good if it can be used, not the more expensive the better; Considering the cost factor of the mold, the mold steel should be selected with materials corresponding to the mold life to avoid unnecessary waste; The lifespan of general P20 materials is around 300000; 2738 materials are no problem at 500000 yuan, while H13/2344 materials are usually above 800000 to 1 million yuan, which can be selected according to the situation;
③ The surface treatment of molds is also very important. Nitriding can enhance the surface hardness of steel and effectively extend the lifespan of molds; Electroplating can effectively modify mold steel, and can be used to enhance and improve the performance of steel for some plastic parts that require high brightness and corrosion resistance.
2. Structural design
A mature mold structure not only takes into account product material properties, shrinkage rate, forming temperature, elastic tensile deformation coefficient, etc., but also takes into account cooling water channels, mold opening and closing speed, etc. A reasonable mold structure can effectively extend the lifespan of the mold, ensure smooth production of the mold, improve efficiency, and reduce costs.
3. Mold processing
If you want to do good work, you must first sharpen your tools. The arrangement of mold processes is particularly important, as a reasonable process arrangement can accelerate the production cycle, shorten processing time, and effectively save costs. And more importantly, precise and reasonable processing can ensure the stability of the mold during the production process and extend its lifespan. Some machining errors can lead to mold welding, and no matter how well the welding is done, it is a loss for the mold; In addition, poor processing may also affect the mold action, reduce the mold life, and cause the mold to crack or even break during the production process.
4. Standard parts
The lowest wooden bar determines the capacity of the bucket. Everyone understands this principle, but they often fail to pay attention to it when doing it. The same is true for molds. Although standard parts are not directly involved in forming, they control the operation of the entire mold. A good standard component should be wear-resistant, hard enough, with high accuracy, and should not deform. There is a significant price difference between standard parts from different brands, so when making molds, don't just haggle over prices. Kill and kill, as your molds have dropped from Mercedes Benz to Volkswagen.
5. Collision (flying mold)
It is the experience of a mold fitter that comes into contact, but seemingly simple tasks are the most technically challenging. The main focus of complex molds is on this skill. A flat mold is the simplest, as long as there are no flash gaps on the fractal surface, it is basically okay. Moulds for automotive parts are very troublesome, not only have irregular fractal surfaces, but also often include multiple sliders and top blocks. At the same time, it is a comprehensive work to improve and improve other issues of the mold through collision.
6. Polishing/leather grain
The polishing of the mold is the final step in the manufacturing of the mold. Polishing is directly reflected on the plastic parts, so this is the most prestigious job. Polishing can also help and supplement mold movements, especially for demolding. Often, some mold production is not smooth due to poor polishing, excessive resistance, difficulty in demolding, and even top whitening and cracking.
7. Mold assembly
Mold assembly is like assembling a machine, where every component and screw must not go wrong. Otherwise, the consequences can be quite serious, ranging from product defects and affecting production to complete damage to the mold and resulting in scrapping. So the assembly work must be very meticulous. During the assembly process, it is particularly important to pay attention to the cleanliness of the mold, especially the waterways and screw holes, and be sure to blow out the iron filings inside.
8. Hot runner or cold runner
This actually has the least impact on the quality of the mold, as the hot runner is usually designated by the customer's brand, especially for some major customers. Foreign well-known brands do a very good job in both quality and after-sales service, so there is generally no problem with quality. However, there is a significant difference in the quality of some domestic hot runners. Some small businesses, in order to save costs and strive for price advantages, use unreliable heating and conduction accessories, which can easily lead to problems. The main problem with cold runner is how to ensure the balance of injection molding, gate size, injection pressure, and so on.
9. Cooling water circuit
Those who have experience with molds know how important cooling is for a mold. Due to the increase in prices and labor wages, it is unimaginable to generate profits without reducing the injection molding cycle by one second during mass production of products. However, accelerating the production cycle will also lead to an increase in mold temperature. If not effectively controlled, it will make the mold unable to form due to being too hot, and even lead to mold deformation, failure, and scrapping. So excellent waterway design is particularly important, including the layout density, diameter, and connections between waterways.
10. Mold maintenance
Mold maintenance mainly refers to the maintenance and upkeep during the production process. A mold is like a car, and if left unused for a long time without proper maintenance, it may lead to the mold being scrapped. So every time the mold is used, comprehensive maintenance should be carried out, especially for the rust prevention of the forming 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 fall asleep during installation or disassembly, so it is necessary to ensure that the mold is dry and then apply a layer of oil for protection.
Nylon drag chains are made by injection molding using molds, and the quality of the molds directly affects the quality of the drag chains. A good mold is worth having.