How to Determine the Adding Proportion of Different Steel Balls?

As we all know, the function of the ball mill is to grind the material through the friction and impact between steel ball and steel ball, or steel ball and liner. But if the steel ball inside the ball mill are all the same size? How to determine the proportion of steel ball in ball mill?

The size and proportion of steel ball of ball mill should be determined according to many factors, such as the diameter of ball mill, the hardness of ore, the particle size of feeding material, hardness (quality) of steel ball and milling speed.

When the type of the ball mill is determined, the milling speed of will be set. In addition, the hardness of ore is measurable, and the particle size of the ball mill can be determined by changing the size of the screen grid.

Normally, there is a running in period for new ball mill. In the process of running in, the adding quantity of steel ball for the first time should account for 80% of the total ball loading. The proportion of steel ball can be decided according to the size of steel ball (Φ 120 mm, Φ100 mm, Φ80 mm, Φ 60 mm, Φ 40 mm).

Different types of ball mill have different ball loading. For example, MQG1500 x 3000 ball mill (processing capacity is about 100-150 tons) has a large amount of ball loading, which is up to 9.5 to 10 tons. Adding a large steel ball for the first time (Φ120 mm and Φ100 mm) reaches 30%-40%, and the small steel ball (Φ 60 and Φ40 mm) accounts for 30%.

Why the amount of steel ball only be 80% in the process of running in? After installed, the large gear of ball mill should engage with the small gear, and the processing capacity will be increased gradually. When the ball mill runs normally for two or three days, the operator should stop the ball mill and check the engaging of the gears. If there is no exception, open the manhole cover of the ball mill, and add another 20% steel ball mill. When the ball mill restarts normally, adding the steel ball for each class should be in a proportion — 3:4:3 (Φ 120 mm for 3, Φ100 mm for 4, Φ 80 mm for 3).

The addition of the small steel ball just matches with the first time of adding ball. This is because there is some reasonable grinding between steel ball and steel ball, steel ball and ore, steel ball and liner when the ball mill runs normally, which can increase the abrasion and make the large ball mill become the medium or small one and the medium one become the small one. So, don’t add the steel ball when the ball mill runs normally. If the available mineral granularity is not dissociated and the fineness of ball mill cannot meet the requirements of flotation, an appropriate amount of small steel ball can be added.

It is necessary to make a reasonable supplement of steel ball and reduce the abrasion in order to maintain the reasonable proportion between the filling ratio and the steel ball and maintain the stable operation of the ball mill,

The weight of steel ball depends on the quality of steel ball and ore consumption. The steel ball addition should be calculated according to the amount of ore per ton (i.e., 0.8kg steel ball per ton of ore). Generally, each ton of ore needs 1kg—1.2kg steel ball.

Different types of ball mill have different proportions. If the diameter of ball mill is under 2500 ㎜, the size of steel ball should be Φ100 mm, Φ80 mm, Φ60 mm, otherwise, the size of steel ball should be Φ120 mm, Φ100 mm, Φ80 mm.

All in all, the ball mill needs different sizes of the steel ball, and it is very important for the operation and production efficiency of the ball mill to keep a reasonable proportion of different steel balls. Xinhai hopes that every user can control this proportion and finish the production better.

Tags:steel ball, ball mill,

From:Xinhai Mining Machinery Company