Do you know how to balance the ball in a ball mill?
Date：2019-09-29 16:48 Source：cementepcViews:
Ball mill is one of the commonly used equipment in mineral processing equipment. The reasonable ball mill loading quantity not only affects the improvement of grinding efficiency and production theory, but also relates to the service life of the ball mill.Therefore, it is very important to master how to balance the ball in the ball mill.The following will introduce the ball mill load the amount of the relevant problems.
1. Ball loading capacity and output of ball mill
The output of the ball mill is directly related to the amount of ball loaded.When a ball mill works, its efficiency is generally determined by the total amount of work done by each ball (number of hits and force of impact).Therefore, the efficiency of each ball must be brought into full play, which means that the ball moving along different tracks should be limited to no collision as far as possible.Too much, the steel balls overlap with each other, so that part of the steel balls fall down less than the required height, unable to give full play to the crushing capacity of each steel ball, at the same time, increase the kinetic energy consumption.Too little. Although the crushing capacity of each steel ball is fully developed, the total crushing capacity is still limited.Therefore, the appropriate amount of ball must be selected.
According to the actual results of the laboratory, when the filling amount of steel ball in the cylinder is 40%, the output is the highest, while the filling rate of general steel ball in production is about 35%, that is, the volume of ball filling is kept lower than the horizontal center line.
2. What is the most appropriate amount of ball in the ball mill?
When the speed of the ball mill is fixed, the volume of the ball only accounts for 10% of the cylinder volume of the ball mill.The ball mainly moves in the form of sliding, and the ball has no possibility of running.When the ball load gradually increased to 30 percent, although the ball movement is still mainly sliding, but has begun to appear the tipping we need.When more than 40% of the ball is loaded, the ball's movement will be in the form of tilting.When the capacity of filling the ball reaches 50% of the total capacity of the cylinder, because the surface of the ball group is just on the diameter line of the cylinder, it is easy to produce tilting.Therefore, it is more suitable to load balls between 1/3 and 1/2, and 1/2 is the best.
3. How to detect whether the ball loading amount of the ball mill is appropriate?
The size and proportion of ball loading should be taken into consideration. As for the number of ball loading, it has been basically fixed in production. For example, the ball loading volume of the central ore discharge ball mill is limited to prevent the steel ball from rolling out of the ball mill, while the ball loading volume of the lattice ball mill should account for about 50% of the total volume.During the test, the operating conditions such as feed size of the ball mill, overflow fineness of the classifier and sand return should be kept the same as far as possible, and then the rationality of ball loading proportion can be checked from the following two aspects.
(1) the amount of ore feed and overflow fineness of classifier remain unchanged, while the amount of sand return decreases, indicating that the grinding function of ball mill is strengthened, and the amount of ore feed can be increased.
(2) if, according to the screen analysis results of sand return by the classifier, it is found that the number of ore particles close to the overflow size increases, it indicates that the number of pellets is insufficient;On the other hand, an increase in coarse grains indicates an insufficient number of large spheres.