Evaluation of Large Grinding Mill Drives for the Cement Industry

Mill drives for the cement industry have rapidly increased in horsepower during the past few years. There appears to be no limit in size. Because of this increase in horsepower, the application problems have become more complex. The usual type of mill drives may not provide the optimum performance and cost. Nonconventional drives should be included in the evaluation. The significant types of drives available are reviewed, and the electrical performance and economics of each type are evaluated. Gearless-type drives are in the study. Gearing, however, is not included in the evaluation. No attempt is made to recommend one drive over any other.