Torsional vibration calculation and analysis of tube mills

It is noted that torsional vibration considerations of the tube mill are very important for the normal operation and design of tube-mill drive systems. The theoretical basis for obtaining mathematical models of the mill torsional-vibration system is discussed. The dynamic parameters of the practice tube-mill system in cement plants are calculated by using state-space representation and complex modal analysis techniques. Also examined is the damping of tube-mill torsional vibration, including such techniques as electromagnetic damping, oil damping, and grinding medium damping. It is shown that these dampings have a powerful effect on the dynamic response of the mill drive system. Experimental research performed on tube-mill systems in cement plants is also reported. The test data and calculated results are shown to agree very well