Jan 07, 2015 CEMENT INDUSTRY Cement Mill Notebook QATAR NATIONAL CEMENT COMPANY DOHA-QATAR 2010 [email protected] . ... knowing the total number of plates per ring or rotation of the mill. Angle α = (n * 360/ N ) Where; n: Number of visible plates N Total number of plates per ring or rotation of the mill. 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36