The roller mill is the main equipment for milling section in flour mills. It mainly depends on a pair of differential transmission and relative rotation rolls to break wheat, meanwhile, scrapes endosperm from wheat bran, then endosperm grinding into flour. The material can be extruded, sheared and broken during the equipment working and so as to achieve a certain grinding effect, each roller mill has two independent drive, feeding, and grinding systems and play their functions in the flour passages.