Abstract: In order to enable the Nalinhe No.2 Mine Washery to increase washing capacity and efficiency and cut down operating cost, work is made on optimization of the irrationally designed double-toothed roll crusher, constant-weight loading system, pump shaft seal water cooling system and power distribution protection system.Practice shows the optimization work has led to the increase of the capacity of coarse coal washing system from 1 500 t/h to 2 500 t/h, sharp rise of truck loading capacity and accuracy, higher reliability of washing system and thorough elimination of maloperation in power distribution.This brings about not only a favorable economic result, but also provides the basis for ensuring safe and civilized coal washing operation.