Thermal cooling technology for plastic mold steel
What is Thermal Cooling Technology?
Thermal cooling technology refers to the control of the molding temperature and time of plastic products by heating and cooling the mold. In the plastic injection molding process, the mold not only needs to withstand the environment of high temperature and high pressure, but also needs to withstand the repeated action of cyclic heating and cooling, which requires the mold to have high strength, high hardness and high wear resistance.
What are the benefits of optimizing thermal cooling technology for plastic mold steel?
Optimizing thermal cooling technology for plastic mold steels can bring the following benefits:
Improve molding efficiency: By optimizing the thermal cooling technology, the molding cycle can be shortened and the production efficiency can be improved.
Improve product quality: By finely controlling the temperature and duration of the mold, you can reduce the shrinkage, deformation, bubbles and other quality problems of plastic products.
Improve mold life: Optimized thermal cooling technology can reduce mold wear and cracks, and extend mold life.
How to optimize the thermal cooling technology of plastic mold steel?
Here are a few aspects of optimizing the thermal cooling technology of plastic mold steel:
Optimize the design of the mold
The design of the mold should take into account the thermal cooling technology, including the cooling channels inside the mold, the heating system, etc. By optimizing the location and number of cooling channels, a uniform temperature distribution can be achieved to reduce temperature fluctuations during the molding process, and by optimizing the heating system, the temperature of the mold can be optimal, improving molding efficiency and product quality.
Choose high-quality mold materials
High-quality die steel has high hardness, high wear resistance and high thermal conductivity. By selecting high-quality mold materials, the mold can have better wear resistance and heat conduction performance, so as to ensure the service life and product quality of the mold.
Precise control of the temperature of the mold
Precise control of the temperature of the mold can avoid thermal stress in the molding process and reduce quality problems such as shrinkage, deformation, and bubbles of plastic products. Precise control of the mold temperature can be achieved by installing temperature probes, heating plates, and other devices.
Set a reasonable cooling time and cooling rate
Formulating a reasonable cooling time and cooling rate can avoid quality problems such as deformation, discoloration, and bubbles in the finished product. This can be achieved by decreasing the cooling time and increasing the cooling rate.
Plastic mold steel has good dimensional stability and high-precision forming ability, so it has been widely used in production. However, as the temperatures used in the production process are constantly changing, plastic mold steels are subject to thermal expansion and contraction.
The principle of thermal expansion and cold contraction
Thermal expansion and contraction refers to the phenomenon of volume change in an object as its temperature changes. When the temperature increases, the thermal motion of the molecules in the object intensifies, and the distance between the molecules increases, thus increasing the volume of the object, and when the temperature decreases, the opposite is true.
In plastic mold steel, this phenomenon of thermal expansion and contraction can cause a change in its size, which will affect the accuracy and quality of the molding. Therefore, it is essential to study the thermal expansion characteristics of plastic mold steel to ensure the stability of production and the quality of products.
Coefficient of thermal expansion of plastic mold steel
The coefficient of thermal expansion of plastic mold steel refers to the amount of change per unit length (usually expressed as α) with the change of temperature. Different plastic mold steel types have different coefficients of thermal expansion, usually around 20°C, with α values around 10-6°C.
In mold manufacturing, due to the thermal expansion and contraction characteristics of plastic mold steel, it is necessary to consider the temperature control during the molding process, and an anti-stick coating is often applied on the surface of the mold to avoid deformation and adhesion.
Factors influencing thermal expansion properties
In addition to temperature, the thermal expansion characteristics of plastic mold steels are influenced by the following factors:
1. Composition of steel: Different compositions of steel have different crystalline structures and lattice constants, so the coefficient of thermal expansion will also be affected.
2. The hardness of steel: The hardness of steel is related to its lattice morphology, intermolecular distance and other factors, so the harder the steel, such as the quenched steel, the smaller the coefficient of thermal expansion.
3. Heating method: The heating method of steel will also affect its thermal expansion characteristics, such as fast heating and slow heating will lead to different thermal expansion and contraction effects.