10 points to note when opening the injection mold

Before the injection mold is opened, we must determine the product requirements. For example, what materials are used? Which supplier supplies it? Different suppliers of the same material will shrink differently. What are the requirements for parting lines? What are the requirements for appearance? Do you want to etch? Or polished? If post-processing is required, such as spraying, molds must be considered.

       After clearing the above questions, today I will tell you about the matters needing attention when opening the injection mold:

•        1. The injection mold should choose a reasonable exhaust position and its amount control. Otherwise, the plastic injection will be dissatisfied and the product will be “out of stock”.
•        2. The injection path should be selected reasonably, so that the material can reach each place evenly (equal flow path), and there must be sufficient storage to ensure that the plastic is replenished during the shrinking process.
•        3. Select a reasonable demolding method, choose a reasonable position and number of ejector pins, and ensure that the product is not damaged during ejection.
•        4. The shrinkage coefficient of each material is different, and the mold must have a reasonable shrinkage rate.
•        5. Post-processing of injection mold material is not needed, because the plastic is soft, no special requirements such as hardness, and the heat treatment process may cause mold deformation.
•        6. The cooling (water passage) in the injection mold is related to the product size, shape, plastic properties, holding time and other factors.
•        7. The roughness level in the cavity of the injection mold must reach "mirror level", otherwise the product is difficult to demold, and the product needs to be overpowered when ejected, causing product damage. The roughness of the positioning pin, the clamping surface and other parts are all standard.
•        8. The injection mold must have sufficient rigidity, otherwise deformation will occur during mold clamping and holding, which will cause "flash".
•        9, the mold and the injection molding machine should be fixed in a reasonable manner, must be reliable and firm to prevent accidents caused by displacement during mold clamping. And easy to disassemble.
•        10. When the mold does not have a return spring, it moves with the injection molding machine together with the moving mold part. The mold ejector plate and the ejector rod of the machine are connected together (commonly known as strong ejection).