The advantages of grate-type ball mills are fast discharge speed, reduced over-grinding of ore, and increased output per unit volume, resulting in higher output than overflow-type ball mills. Their disadvantages include complex structure, susceptibility to grate clogging during discharge, difficult and complex maintenance, and relatively low operating rate.
The advantages of overflow-type ball mills are simple structure and convenient maintenance. Due to the reverse-threaded discharge pipe, large pieces of ore and steel balls are not easily discharged. Their disadvantages include lower production capacity per unit volume, lower throughput, and a higher susceptibility to over-grinding.