Molten Metal Transfer Pump

The molten metal transfer pump comprises a case, in which a drive-connected shaft with the mounted impeller is installed on the upper bearing and lower journal plain bearing;

• the lower journal plain bearing comprises rotor and stator parts;
• the rotor part is made in the form of two bushings, mounted on the shaft, and the stator part is made in the form of two bushings fixed in the cage in axial alignment with the shaft;
• bushings of the rotor and stator parts have mating sliding surfaces and are made of silicon carbide based ceramics, the pump is characterized in that above the lower journal plain bearing in the opposite areas of the surface of the shaft and case multiple-thread oppositely directed helical grooves forming a labyrinth screw pump are milled;
• bushings of the rotor and stator parts are made in the form of split bushings fixed with flat rings and composed of cylinder segments equidistantly placed in a circumferential direction, located correspondingly in the cylindrical groove of the shaft and cylindrical groove of the cage and fixed with cone hold-down rings radially, and with spring rings axially, providing for axial pressing force.