The drum chipper is composed of frame, knife roller, upper and lower feeding mechanism, feeding device, hydraulic buffer system and electrical control system. It can cut logs, branches, veneers, waste veneers, bamboo, cotton stalks and other non wood fibers into pieces of certain specifications. It is widely used in shaving plant, medium and high density fiber plant, wood straw plant, biomass power plant, wood chip plant and other processes, as well as the necessary equipment in the material preparation section of the production.