As we all know, due to the impact of grinding media, friction energy between the grinding material and ball mill, and the energy released when the material is ground, the ball mill grinder prone to excessive temperature phenomenon, and sometimes the working environment even as high as 40, 50 degrees in the summer. Long-term exposure to such a high temperature brings a certain negative load to the ball mill grinder. Only the miner does a good job in the cooling work of ball mill grinder in the summer, can the ball mill grinder maintain a long period of stable operation. So how do we prevent the abnormal high temperature of the ball mill grinder?
1. Strengthen the internal and external ventilation of the ball mill grinder
The cooling air volume of the ball mill grinder is calculated according to the thermal balance of the ball mill grinder. According to the heat balance of the ball mill grinder, the heat is taken away by the ventilation of the ball mill grinder usually accounts for 20% of the total heat discharging by the ball mill grinder. Enhancing the ventilation can bring the cool air into the inside of the ball mill grinder, dilute the heat molecules inside the ball mill grinder, thus gradually reducing the temperature inside the ball mill grinder. Therefore, we can recombine and modify the internal device of the ball mill grinder to keep the ventilation and heat dispersion.
It should be noted that enhancing the ventilation in the ball mill grinder can reduce the material temperature, but the ventilation in the ball mill is not only limited by system resistance, air lock, air leak, but also restricted by product fineness. Excessive air volume will make the grinding effect of the ball mill grinder worse. Therefore, there is a certain limitation to reduce the temperature of the material by increasing the ventilation inside the ball mill grinder.
2. Add the sprinkler system and refrigerating plant
In general, the grinding system has a lot of equipment and piping, so the heat dissipation surface is large. We can make full use of the surface of the grinding system to enhance the cooling and heat dissipation. For example, spraying the atomized water to the outer wall of the powder separator, make the water tank along the outer side of the spiral conveyor. It is also feasible to spray water from the grinding head or the grinding tail when the ball mill grinder works, but it should be noted that only when the abrasive temperature is higher than 100℃, can we spray the water from the feeding end of the ball mill grinder.
In addition, we can also install the ball mill grinder with the refrigerating plant, which can cool the grinding materials and the surface of the ball mill grinder under the high temperature, so that the temperature of the ball mill grinder can be controlled in the ideal state.
3. Improve the lubricity and maintenance of ball mill grinder
Strengthen the daily maintenance of the ball mill grinder, and timely clean the dust and oil on the machine body, keep the ball mill grinder body clean.
On the one hand, the ball mill grinder operator can add the suitable, sufficient amount of lubricating oil to each rotating bearing of the ball mill grinder, which can prevent the friction and heat phenomenon among bearing components due to less lubricating oil, thus avoiding the problem of abnormally high temperature. On the other hand, we can choose the ball mill grinder that equipped with large and small gear lubrication devices, that is, use the compressed air to spray the dry oil or thin oil atomization to the bearing tooth surface and then form a fine and uniform dry oil layer, which greatly reduces the friction and achieves the dual effect of energy-saving and cooling.
Normally, when the ball mill grinder is running, the temperature rise of the main bearing does not exceed 55℃, the temperature rises of the transmission bearing and reducer do not exceed 55℃, and the maximum temperature rise does not exceed 60℃. When the ball mill is put into continuous operation for one month, all lubricants should be released and replaced with new oil, and the ball mill grinder should be cleaned thoroughly. Besides, the oil should be changed once every six months in combination with the medium repair. Check the lubrication condition and oil level of each lubrication point of the ball mill grinder at least once every four hours.
4. Add the grinding aids
In order to solve the problems of excessive temperature in the grinding system, resulting in serious overgrinding phenomenon and decreasing the grinding efficiency of the ball mill grinder, we can use grinding aids to reduce the degree of internal adhesion of the ball mill grinder, which can improve the grinding efficiency of the ball mill grinder and reduce the vicious cycle of high temperature.
5. Adopt ball mill grinder control cabinet to cool down
The temperature in the electrical control cabinet shall not exceed 40℃, including frequency converter, relay and some rectifier modules, etc. These heating elements will give off heat when they work, and their heat will gather together to raise the temperature in the electrical control cabinet. Therefore, we must cool the electrical control cabinet, mainly including the following three methods:
• Air fan
The air fan is mainly used when the cabinet temperature is higher than the ambient temperature. Generally, the front door of the cabinet or the bottom sidewall is used as the air inlet to install the filter grid, and the upper is used as the exhaust port, which is installed with the filter grid for preventing the impurities.
• Industrial air conditioner
The industrial air conditioners can be used if the ambient temperature is higher than the cabinet temperature, which can carry out the constant temperature control of the cabinet temperature, and prevent the outside harmful, humid gas or dust into the control cabinet.
• Heat exchanger
If the air circulation inside and outside the cabinet is required to remain isolated, we can use heat exchangers (wall-mounted type and top-mounted type) to cool down, mainly including air/air heat exchanger and air/water heat exchanger.
Ball mill grinder run under the high temperature for a long time without cooling measures will greatly reduce the grinding efficiency of ball mill grinder, shorten its service life, increase maintenance workload, which not only causes damage to the ball mill itself, reduces the performance of ball mill grinder, but also cause the unqualified grinding product. Therefore, it is very necessary to control the temperature of the ball mill grinder in the summer.
The above five methods solve the problem of the high temperature of the ball mill grinder in summer. The ball mill operator can keep the temperature of the ball mill grinder in the appropriate range, prevent the overheating of ball mill in summer, and give full play to the work efficiency of the ball mill grinder.
From:Xinhai Mining Machinery Company