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How to make a good plastic box mold

Update:20-10-2021
Summary:

1. Use the correct steel for the core, cavity and mold […]

1. Use the correct steel for the core, cavity and mold base, and use high toughness steel for the inserts.
For example, if one box mold is made with two boxes, then we need to use pre-hardened steel with a hardness of 28-32 degrees as the mold base. For more durable mold parts, we also need to choose the right steel.
2. Select the correct quenching method to heat-treat the core, cavity, slider and inserts, and control the hardness of the steel. Generally, the hardness of the steel cannot be too high. It is not that high hardness is good for the life of the mold. Sometimes, the hardness is not so high but it is better for the mold, because it is easy to break if it is too hard.
3. The guiding system and sliding area of ​​the box mold must adopt high-precision machining technology. No manual operation is allowed, otherwise it will cause problems in the operation of the guiding system and the slider area.
4. The hot runner system is very important for both large and light boxes. Therefore, we conduct mold flow analysis for plastic box molds that require hot runner systems. In order to fill plastic materials in a balanced way, we need a very special hot runner system. If we need to form a durable plastic box, then use low melt flow index HDPE, such as MFI=3-4 or even MFI=7-8……
5. The cooling must achieve the optimal effect in order to reduce the molding cycle and save costs. For the durability of the plastic box mold, the best cooling channel design should be used in the largest molding area. For single-use boxes, quenched steel is required, and a good cooling system design...
6. If you currently do not have an injection molding machine, but plan to purchase a new machine, we recommend that you directly purchase a high-speed injection molding machine for production operation, and the screw speed needs to be greater than 350. Now, all over the world, many plastic box manufacturers use accumulators to increase the melt and injection speed.
7. Of course, plastic box mold design is the most important thing. When ejecting, it is best to use mechanical ejection, so that we can perform ejection action when opening the mold. Of course, if your machine can work with two hydraulic actions at the same time, it can also be ejected when the mold is opened.
8. For all molds, high-speed operation is based on precision machining of the mold and precise guidance of moving parts...Otherwise, the mold cannot have high-speed operation performance.