Due to the bumping and friction of the grinding balls, a lot of heat is often generated in the ball mill jar, which leads to an increase in the temperature in the ball mill jar, and the increase in temperature has a certain impact on the grinding of some samples. To prevent such a situation from appearing , it is necessary to control the temperature of the ball mill tank, but the planetary ball mill is a high-speed rotating equipment, how to cool it down?
In order to solve the temperature control problem of the ball grinding tank of the planetary ball mill, there are three temperature control methods, namely pre-freezing, air-cooled temperature control and water-cooled temperature control:
1. Pre-freezing
Pre-freezing is to put the added samples and grinding balls, and the sealed ball mill tank into a liquid nitrogen tank, reduce the tank temperature to a relatively low standard, and then take it out and put it into a planetary ball mill for grinding. End grinding before high, thus ensuring low temperature grinding of the sample. The method of pre-freezing is not particularly simple in practice, and protective measures must be taken to prevent frostbite by liquid nitrogen. In addition, this method is only suitable for sample grinding in a short time. If the grinding time is long, the temperature in the tank will increase a lot, and the effect of low-temperature grinding will be lost.
2. Air-cooled temperature control
The air-cooled temperature control design principle is relatively simple, that is, a sealed cooling cover is installed at the working part of the ball mill, and then the refrigerant is introduced into the cooling cover when the equipment is working, and the main wheel of the planetary ball mill will form a negative pressure center when it rotates at high speed. , so as to create a low temperature environment, and the refrigerant takes away the heat generated by the ball mill and then discharges it. The air-cooled temperature control is more suitable for the temperature control of the stainless steel raw material ball mill. Because the metal has good thermal conductivity, the heat dissipation effect is relatively good, but if the ball mill of other raw materials is used, such as nylon, agate, zirconia, etc., this kind of The effect of the temperature control method is relatively general, and the refrigerant consumption is large and the use cost is high.
3. Water-cooled temperature control
The water-cooled temperature control is to directly cool the ball mill tank. It uses a special ball mill tank. The ball mill tank is equipped with an interlayer, and liquid refrigerant can be introduced. The refrigerant directly contacts the ball mill tank to take away the heat generated. The liquid refrigerant enters the ball mill tank through the pipeline, and flows out through the pipeline. After being cooled by the external temperature control equipment, it is recycled. The water-cooled temperature control method solves the problem of the thick wall of the ball mill tank and poor heat dissipation, and the refrigerant continues to pass in and is cooled by the external low temperature equipment and then circulated, so that the ball mill tank can always be in a low temperature environment, and the temperature control effect is more effective. good.
