Grinding media balls are manufactured from steel and cast iron. These are used as a medium in a Ball mill which is a horizontal cylinder partly filled with the media balls that rotates on its axis, imparting a tumbling and cascading action to the balls. Material fed through the mill is crushed by impact and ground by attrition between the balls. Mostly these balls are used in the manufacturing process. There are various types of balls. Each of the balls has specific features it means a lot for the special production process.
When comes to milling and dispersion process like in cement production, there are more chances for material damage and then splits. In order to avoid such thing grinding balls are used. The balls are made of heavy metal and other material thus undoubtedly there the pressure will be high. If the pressure gets impacted on the material then it will offer pressure to the particles. It will completely reduce the size of the particle at the same time you will have resulted with finite particles. In short, contamination is the actual reason to use grinding balls. It will make the particles to decrease in size.