Abstract: The invention concerns a floating-ring seal in which the ring is disposed so that it can move freely inside an annular chamber. Of the four walls of the chamber enclosing the ring, two walls disposed at an angle to each other are stationary while the walls opposite them rotate at the speed of the drive. As a result of the freedom of motion of the floating ring and the drive and braking torques acting on it through the walls, the ring rotates at a speed which is lower than the speed of the rotating components.

Abstract: The rotor of a thrust bearing for the horizontal shaft of a centrifugal pump is installed in a housing which is mounted in an oil-containing vessel and has an inlet below and an outlet above the oil level. The peripheral surface of the rotor has a groove which receives a portion of an annular stator to form a suction channel which draws oil from the vessel through the inlet when the shaft is driven. The oil fills the housing and is returned into the supply of oil in the vessel by way of the outlet, a cooling unit and a filtering cartridge.

Abstract: A submersible motor pump wherein the thermal barrier between the pump housing and the motor housing contains at least one bellows or at least one cylinder and piston unit storing a supply of liquid for admission into the motor housing so as to maintain the motor housing in filled condition. The contents of the motor housing are circulated and cooled by a high-pressure cooler, and the liquid which is to be conveyed from the pressure equalizing device into the motor housing when the pressure of liquid in the pump housing rises is admitted into the motor housing by way of the cooler so that it is cooled prior to entering the motor housing.

Abstract: The passage in a wall which separates the interior of the housing of a glandless submersible motor pump from the surrounding atmosphere is normally sealed by an annular seat which is placed against the end face of a muff forming a detachable part of the wall, and by a temperature- and pressure-resistant ceramic sleeve which surrounds an elongated metallic conductor and normally bears against the seat owing to the pressure differential between the interior of the housing and the surrounding atmosphere. If the sleeve is destroyed, a normally confined plunger of the conductor bears directly against the seat to prevent escape of fluid from the pump housing. That end portion of the conductor which extends into the housing is surrounded by one or more layers of insulating tape and by a tubular sheath which is shrunk onto the tape and exhibits at least some thermal-shock-absorbing characteristics.

Abstract: A submersible motor pump assembly has a motor which is installed at a level below the pump. The shaft which is driven by the motor and rotates the impeller or impellers of the pump is spacedly surrounded by a tubular member of a thermal barrier in the region between the upper end of the motor housing and the lower end of the pump casing. The solid impurities, especially magnetizable particles, which are circulated by the pump tend to penetrate into the motor housing by way of the clearance between the tubular member and the shaft, and the penetration of such impurities into the motor housing is prevented by an apparatus which conveys a stream of liquid from the discharge nozzle of the pump casing into the clearance and contains a filter with several electromagnets which intercept magnetizable particles and allow a clean stream of flushing liquid to flow into the clearance.

Abstract: A motor-pump aggregate whose pump is a glandless centrifugal pump and is intended for use in a nuclear reactor plant has hollow coaxial pump and motor shafts which are sealingly coupled to each other. To this end, the first end portion of the pump shaft extends into the adjacent first end portion of the motor shaft and has an external conical shoulder for engagement with an internal conical seat of the first end portion of the motor shaft. A feather holds the first end portions against rotation relative to one another, and the shoulder is urged against the seat by a pair of threaded connectors one of which is anchored in a disc-shaped member in the region of the second end portion of the motor shaft and the other of which is anchored in the first end portion of the pump shaft. The disc-shaped member and the second end portion of the motor shaft have mating ring gears to ensure accurate and a reproducible centering.

Abstract: A hydrostatic seal for the upright shaft of a coolant circulating pump in a nuclear reactor plant has a first sealing element which is affixed to the shaft and a second sealing element which is axially movably mounted in the pump housing and defines with the first sealing element an annular control clearance gap wherein leak fluid flows from a high-pressure compartment which surrounds the sealing elements to a low-pressure compartment between the shaft and the housing. An auxiliary pump causes the fluid to circulate in response to rotation of the shaft along an endless path which is defined by the high-pressure compartment, an annular space a portion of which is adjacent to that end face of the second sealing element which is remote from the gap, a flow restrictor between the high-pressure compartment and the space, one or more passages which are machined into the housing, and a chamber which communicates with the high-pressure compartment by way of the auxiliary pump.

Abstract: An outer tubular member is adapted to be connected at one end with the wall of a pressure vessel, such as a reactor, and an inner tubular member is rigidly connected with and extends coaxially through the outer tubular member. A portion of the inner tubular member extends beyond the outer tubular member into the interior of the pressure vessel, and a pump shaft extends through the inner tubular member. A radial bearing for the pump shaft is located in the aforementioned portion of the inner tubular member and a pump wheel is connected with the pump shaft within the pressure vessel. A pump shaft seal is located in the inner tubular member within the confines of the outer tubular member, and arrangements are provided for sealingly connecting the inner and outer tubular members with one another, and for carrying exteriorly of the pressure vessel an additional bearing.