10 factors affect the quality of injection molds
Producing mold is a complex process from designing, machining, assembling, testing to the final producing parts. In the whole process, there are 10 factors impact the quality of the mold!
- Price The higher steel price, the better? No! In consideration of the cost, the steel should match the mold life to avoid unnecessary waste. For example, P20: 300,000; 2738:500,000; H13/2344:900,000. You can choose the steel according to the volume.
- Surface treatment Nitriding: increase the surface hardness of steel, effectively extend the mold life; Plating: change the properties of the steel(You can use plating for the high-brightness and corrosion-resistant plastic parts)
Good mold structure not only consider the material properties, shrinkage, molding temperature and elastic, tensile, deformation coefficient etc. Also need to think over the cooling line, the speed of mold moving. Reasonable mold structure can extend the mold life and ensure the production, improve the effectiveness, reduce cost.
Mold machining process is very important. Reasonable process can accelerate the production to cut the cost effectively. And the precise machining can guarantee the stable and mold life during the production. Bad machining will effect mold(appear cracks, even break). Machining error will cause mold welding that would be a great lose.
Although standard components are not directly involved the molding, they are control the running of the whole mold. Good standard parts should be wear-resistant, hard, high precise, not easily deformed. Different standard parts have many different of the price, so do not blindly bargain or your mold will go straight from Mercedes to Vw.
Fit mold depend on the experience of the bench worker. It looks easy but the most technical work. It's troublesome to fit the auto mold with the irregular parting line and multiple sliders, blocks. They can solve other issues by fitting mold. So it's a comprehensive work.
Polishing is the final section of the mold production. It'll effect the products. Sometimes, it causes mold release, even whitening and cracking.
Assemble mold is same with assemble machine. Every parts, every screws can't make a mistake or the consequences will be serious(Leading to products defects, in serious cases damage the mold). Therefore, the assembly work must be very detailed. During the assembly process, it is especially necessary to pay attention to the cleaning work of the mold, especially the waterway and screw holes, and must blow clean the iron scraps inside.
8.Hot runner or cold runner
Actually, the runner has the least impact on the quality of the mold, because the hot runner is generally a customer-specified brand. Well-known brands are in place regardless of quality and after-sales service. However, in order to save cost, individual small businesses have to strive for price advantages, and use some heating and conduction accessories that are not reliable enough to cause problems. The main problem of cold runner is how to ensure the balance of the injection molding, gate size, injection pressure and so on.
Since the price and labor cost have risen, it's unthinkable to reduce the profit from a one-second injection cycle when mass-production products. But at the same time as the speeding up the production cycle, the temperature of the mold will increase. If it isn't effectively controlled, the mold will not be able to produce because it's too hot, and even the deformation of the mold will be invalidated. Therefore, excellent waterway design is particularly important, including the arrangement of waterway density, diameters, links between them, and so on.
Mold maintenance is mainly the maintenance during the production process. The mold is like a car. If it is not used for a long time and it is not maintained, it may cause the mold to be scrapped. Therefore, every time after the mold is used, it must be thoroughly maintained. In particular, the rust prevention of the molding part and the rust prevention of the main action parts. Because the mold needs to receive water during the production process, water may get on the mold during the installation or disassembly process, so it must be ensured that the mold is dry, and then brush a layer of oil protection.