Ball Mill

I. What is a ball mill?

Ball mill, also named sag mill, tube mill, tumbling mill, rod mill, is the most classic mineral processing equipment to make fine powder and sand-sized granules. This type of grinding machine is to put a certain number of steel balls in its drum-shaped grinding chamber as grinding medium, the materials are crushed and ground by the impact of the falling steel balls.

                                                                                      ball mill grinding plant

II. Ball mill working process and structure

How does a ball mill work?

*The main body of a ball mill is a big round shape cylinder with a big gear on one end, in the cylinder, added many steel balls as the grinding medium.

1. The motor drives the ball mill to rotate through the big gear on the end of the ball mill.

2. The rotation of the ball mill generates centrifugal force, which brings the steel ball to a certain height and then falls down, which has a heavy impact and grinding effect on the material.

3. During a wet grinding process, the final product is discharged along with the flow of water. During a dry grinding process, the final product is discharged along with the airflow.                                  

IV. Ball mill with air classifier in powder and cement industry 

Ball mill can work together with an air classifier for producing fine powder with dry process of 30 microns to 100 microns for materials such as limestone, calcined bauxite, silica sand, etc. In cement industry, two-chamber ball mills or three-chamber ball mills are widely used for grinding cement clinker with high-efficiency air classifier, the final cement specific area is about 360㎡/kg.

     (ball mill with air classifier for 100-45 micron dry powder process)                             (Latest O-Sepa classifier for cement ball mill)

V. Ball mill with screw classifier in gold mining and ore dressing

Ball mills are also widely used in rock gold ore extracting, copper ore dressing and other mineral processing plant as the main size reduction equipment. In these projects, ball mills are working together with screw classifier and the process is with water. Fine particles will overflow and come out from the grinding chamber for the classifier to select particles that meet the fineness requirement for the following flotation machine or gravity classifying equipment.               

          Ball mill in large-scale gold mining proejct                                                     Ball mill in iron ore flotation project

VI. Technical parameters of ball mill