Ball Mills operate with a wide range of material types and hardnesses, and reduce materials to very fine sizes. They are also effective for blending of some materials. Jars and grinding media are available in a wide variety of material types to optimize performance characteristics for long-term wear-resistance, low contamination levels, or economical operation.
Jar Mills are cylindrical jars, placed horizontally on powered rollers and use grinding media in spherical or cylindrical shape. The sample is placed in the jar along with a pre-determined amount of grinding media and rotated on the rollers as the media breaks down the material through abrasion and pressure. The process can be performed wet or dry. Jar mill speeds are relatively slow compared to other types of ball mills.
Planetary Ball Mills operate at higher speeds with increased g forces. The media rolls halfway around the bowl imparting greater abrasion and pressure forces on the sample than Jar Mills. The grinding balls are then launched across to the opposite side of the bowl, adding impact energy to the reduction process.
Mixer mills operate at high speed in one plane with relatively small samples. Oscillation speeds are very high, and the media reduces particle sizes mostly through impact forces.