### Ball Mill Operating Speed Mechanical Operations Solved ...

In a ball mill of diameter 2000 mm, 100 mm dia steel balls are being used for grinding. Presently, for the material being ground, the mill is run at 15 rpm. At what speed will the mill have to be run if the 100 mm balls are replaced by 50 mm balls, all the other conditions remaining the same? Calculations: The critical speed of ball mill is ...