Abstract: Radial runner blades projecting axially from a shroud plate have leading faces inclined from the axial central portions of the blades forward to a cutting edge adjacent to an intake casing wall at an angle of 45.degree.. The trailing wall of each blade is bent to form a reflex angle at approximately its axial central portion, and each blade flares in cross-sectional thickness from its axial central portion toward its edge adjacent to the intake wall. A screw propeller connected to the runner and located at the side of the intake wall opposite the runner facilitates flow of material to the pump toward the casing intake ports, slices sliceable articles into pieces of a size for passage through the intake ports and displaces unsliceable objects for clearing the intake ports.