Rod mill is roughly as same as the ball mill, but there are three distinct differences:

1. The rod mill normally uses the steel rod of 50-100mm as the medium, and the ball mill uses steel ball as the medium. The length of steel rod is 25 to 50mm shorter than the barrel body, the load of rod quantity is 35% to 45% of the effective volume of the rod mill. With the naked eye, the horizontal plane of the rod is about 100-200mm below the center line of barrel.

2. The ratio of the length to the diameter of rod mill is 1.5 to 2.0. Moreover, the internal surface of liner plate on the end cap should be vertical plane. The purpose is to prevent and reduce the disorderly movement, bending and breaking of the steel rod, to ensure that the steel rod has regular movement. The ration of the cylinder length to the diameter of ball mill is small, in most cases the ratio is only slightly larger than 1.

3. The rod mill does not use grid plate to discharge ores, instead is overflow type and open type. The barrel rotation speed of road mill is lower than that of ball will of the same specification, so that the medium in rod mill is in the discharge state.