Determination of Actual Rotary Rate of Ball Mill

AUTHOR: admin DATE: 18 Sep 2012 11:39:02

The actual rotary rate of the ball mill is not the same with the theoretical rate since the determination of the actual rotary speed depends on many factors such as the diameter of the ball mill, production pattern, the shape of the lining board and some other factors. All these factors can never be neglected, so that we are able to figure out the most suitable range for the actual rotary speed.

(1) The diameter of the ball mill.

The larger the diameter of the ball mill is, the working rotary speed of this machine will be. Otherwise, its working rotary speed will be relatively high. As for the powder grinding media with the same ball diameter, the powder grinding capacity of the machine will higher when its diameter is larger.

(2) The production pattern.

In the wet type production pattern, due to the lubricating effect of the water, the abrasion factor between the powder grinding media and the grinding media and the lining board is reduced, and large relative sliding will be produced. For this reason, under the same condition, the rotary rate of the ball mill is 5% higher in wet type grinding than that in dry type grinding.

When the ball mill is operated in the circulated condition, since the flowing speed of the materials inside the mill accelerates, and the production capacity is relatively high, the ball mill has a higher rotary rate in circulate condition than that in the open condition.

(3) The surface shape of the lining board.

The surface of the lining board with bead will reduce the relative sliding of the powder grinding media, increase its elevating height, for this reason, its working rotary rate will be lower than the smooth lining board.

(4) The filing factor of the powder grinding media and the types of the grinding media.

The relative sliding will be large when the filling factor of the powder grinding media inside the ball mill is small, and then the rotary rate will be high.

(5) The property of the materials, granularity of the material feeding and the fineness of the powder grinding.

When the ball mill is processing small-sized soft materials, its working rotary speed is lower than that when grinding large hard materials in the same condition. When the fineness of the powder grinding is small, the main effect relies on grinding rather than impacting, so that the rotary rate will be low.

To make a conclusion, in order to be able to completely reflect these factors, the workers should determine the actual working rotary speed of the ball mill through experience.