injection mold, a few key points to pay attention to when opening plastic molds
Plastic mold opening is one of the most important links in the production of plastic products, and several key points need to be paid attention to to ensure the smooth progress of the mold opening process.
1. Different types of plastic materials have different shrinkage coefficients, so plastic molds must be designed with reasonable shrinkage to ensure that the final product size meets the requirements. Secondly, the plastic mold must have sufficient stiffness to prevent deformation during the pressure retention of the mold, resulting in the “flying edge” of the product.
2. If the product is pushed out at the same time during the mold opening process, it can be achieved through the setting of the thimble page of the injection molding machine, but it should be noted that not all injection molding machines have this function. In addition, when choosing the demoulding method, it is necessary to consider the reasonable position and quantity of the top rod to ensure that the product will not be damaged during the emping process. The design of the cooling system (water access channel) is also crucial, which is closely related to factors such as product size, shape, plastic properties and pressure retention time.
3. The control of the exhaust position and quantity is also one of the points that need to be paid attention to in the process of mold opening the plastic mold. Unreasonable exhaust may lead to insufficient plastic injection, resulting in product “material shortage”. In addition, the fixing method of plastic mold and injection molding machine must be reasonable and reliable to prevent accidents caused by positional change when closing the mold, and it needs to be easily disassembled. In the selection of the injection molding channel, it is necessary to ensure that the material can reach every part evenly, the flow runoff is equal, and there is enough storage to ensure that the plastic is fully replenished during the shrinkage process. In addition, the roughness level in the cavity of the plastic mold should reach the “mirror level” to ensure the smooth demoulding of the product, so as to avoid the need for excessive force when the product is exposed, causing damage to the product. There are also corresponding standard provisions on the roughness of positioning pins, closing surfaces and other parts, which need to be strictly observed.
Plastic mold opening involves many details. Only by strictly checking every link can the quality and production efficiency of the final product be ensured. In practice, engineers should comprehensively consider various key points according to the specific situation, and constantly optimize the mold design and manufacturing process to achieve efficient and stable production.