What is the function of injection molding mold temperature machine?

The purpose of controlling mold temperature and the effect of mold temperature on injection molding parts In the injection molding process, the main purpose of controlling mold temperature is to heat the mold to the working temperature, and the second is 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 the stable and high quality of injection molding parts.
Mold temperature will affect surface quality, fluidity, shrinkage, injection cycle and deformation. Excessive or insufficient mold temperature will have different effects on different materials. For thermoplastics, higher mold temperature will generally improve surface quality and fluidity, but will prolong 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 parts after demoulding.
For thermosetting plastics, a higher mold temperature will usually reduce the cycle time, and the time is determined by the time required for parts to cool. In addition, in plastic processing, higher mold temperature will also reduce the plasticizing time and the number of cycles.
The heat balance control of injection molding machine and the heat conduction of mold are the key to the production of injection molding parts. Inside the mold, the heat brought by plastics (such as thermoplastics) is transferred to the material and the steel of the mold through thermal radiation, and to the heat-conducting fluid through convection.
In addition, heat is transferred to the atmosphere and mold base through thermal radiation. The heat absorbed by the heat conduction fluid is taken away by the mold temperature machine. The heat balance of the mold can be described as P=Pm － Ps. Where P is the heat taken away by the mold temperature machine; Pm is the heat introduced by plastic; Ps is the heat emitted by the mold to the atmosphere.
Plasticizing time,
Preliminaries for effective control of mold temperature The temperature control system consists of mold, mold temperature machine and heat transfer fluid. In order to ensure that heat can be added to or removed from the mold, all parts of the system must meet the following conditions: first, inside the mold, the surface area of the cooling channel must be large enough, and the diameter of the flow channel must match the capacity of the pump (pump pressure).
The temperature distribution in the cavity has a great influence on the deformation and internal pressure of the part. Reasonable setting of cooling channel can reduce internal pressure and improve the quality of injection molding parts. It can also shorten cycle time and reduce product costs. Secondly, the mold temperature machine must be able to keep the temperature of the heat transfer fluid constant within the range of 1 ℃ - 3 ℃, which is determined according to the quality requirements of the injection molding parts. The third is that the heat-conducting fluid must have good thermal conductivity. The most important thing is that it can introduce or export a large amount of heat in a short time. From the perspective of thermodynamics, water is obviously better than oil.
Working principle The mold temperature machine is composed of water tank, heating and cooling system, power transmission system, liquid level control system, temperature sensor, injection port and other components. Generally, the pump in the power transmission system makes the hot fluid reach the mold from the water tank with built-in heater and cooler, and then return to the water tank from the mold; The temperature sensor measures the temperature of the hot fluid and transmits the data to the controller of the control part; The controller regulates the temperature of the hot fluid, thus indirectly regulating the temperature of the mold.
If the mold temperature machine is in production and the mold temperature exceeds the set value of the controller, the controller will open the solenoid valve and connect the water inlet pipe until the temperature of the hot liquid, that is, the mold temperature returns to the set value.