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Mold cooling machine cooling method and injection molding process
announcer：admin
The cooling mode of the mold temperature machine during operation is divided into direct cooling and indirect cooling. Indirect cooling uses a cooling circuit separate from the main circuit, while in direct cooling, the cooling circuit directly participates in the main circuit. Water-cooled mold temperature machine usually adopts direct cooling. The oil-transporting mold temperature machine, because water and oil can not be mixed together during the heating process, they all use indirect cooling, which usually uses a plate exchanger for cooling.
Since the temperature of the mold temperature machine is usually used above 160°C, the internal main pipeline circulates high-temperature steam. At this time, the internal pipeline pressure is relatively large. If the direct cooling method is used, the external water pressure needs to be greater than the internal main pipeline water pressure. In order to enter the main road cooling. This method is prone to danger. Therefore, high-temperature water-type mold temperature machines also mostly use indirect cooling.
Advantages and disadvantages of direct cooling: Direct cooling can only be used in lower temperature occasions, but direct cooling is used to cool down quickly. Advantages and disadvantages of indirect cooling: Indirect cooling is suitable for high temperature mold temperature machines, but the heat exchange speed is slow, and the heat will be lost in the heat exchange. Therefore, when the actual temperature of the medium deviates greatly from the set value, we use a direct cooling method with a large cooling capacity.
The purpose of controlling the mold temperature and the influence of the mold temperature on the injection molded parts In the injection molding process, the main purpose of controlling the mold temperature is to heat the mold to the working temperature, and second to keep the mold temperature constant at the working temperature. If the above two points are successful, the cycle time can be optimized to ensure stable and high quality injection molded parts. Mold temperature will affect surface quality, fluidity, shrinkage, injection cycle and deformation.
Too high or insufficient mold temperature will have different effects on different materials. For thermoplastics, a higher mold temperature will usually improve the surface quality and fluidity, but will extend the cooling time and injection cycle. A lower mold temperature will reduce the shrinkage in the mold, but will increase the shrinkage of the injection molded part after demolding. For thermosetting plastics, a higher mold temperature usually reduces the cycle time, and the time is determined by the time required for the part to cool. In addition, in the processing of plastics, a higher mold temperature will also reduce the plasticizing time and reduce the number of cycles.