Abstract: A fluid pump powered by an integral canned motor includes a housing having a cylindrical passage extending therethrough. A sealed annular stator is mounted around the housing. An impeller assembly is rotatably mounted in the passage in the housing. The impeller assembly includes an axial flow impeller and a sealed rotor mounted around the periphery of the impeller. Bearings, including thrust bearings, are mounted between the periphery of the impeller assembly and the housing. A radial flow auxiliary impeller may be mounted on the impeller assembly to create a radial flow of water from the cylindrical passage in the housing to a peripheral fluid circulation channel between the impeller assembly and the housing. The auxiliary flow impeller pressurizes the peripheral fluid circulation channel.

Abstract: A nuclear reactor coolant pump utilizes a pivoted pad bearing assembly to rotatably mount its shaft through the pump housing. The bearing assembly includes a plurality of arcuate bearing segments disposed end-to-end in circumferentially spaced relation for encompassing the shaft and providing bearing contact therewith, and a plurality of pivot pins each extending radially between an outer annular split ring attached to the pump housing and one of bearing segments. The pivot pins are mounted for universal pivotal movement at their inner ends with the respective bearing segments. The pivot pins at their outer ends are mounted to the annular ring for adjustable radial movement for changing the radial position of the pivot pins relative to annular ring and thereby of the bearing segments relative to the shaft. A plurality of locking cups are provided for coupling the pivot pins in locked relation the annular ring to fix the pivot pins in desired adjusted positions relative thereto.

Abstract: A nuclear reactor coolant pump impeller/shaft assembly, including an impeller nut with a plurality of conduits formed therein in fluid communication with both ends of a passageway formed in the impeller nut in contact with a portion of the shaft, the fluid inlet and fluid outlet of the pump. Due to this conduit/passageway combination, coolant is effectively pumped into the passageway to heat the shaft to a temperature approximately equal to that of the impeller, thus creating thermal balance of the pump's component parts and providing improved pump efficiency.