The present invention relates to centrifugal pumps, and more specifically to a centrifugal pump device with a governor actuated cartridge seal and a method of attaching a centrifugal pump device with a governor actuated cartridge seal. The centrifugal pump comprises a sealing system that prevents undesirable fluid leaking or air ingestion when in operation while allowing ease of installation and maintenance. The governor actuated cartridge seal automatically increases sealing capabilities by urging a movable seal as a function of impeller or engine drive shaft rotational speed. The governors actuate radially so as to present a minimal profile and therefore not introduce a safety hazard. Scalable weights attached to the governors allow predictable calibration and initialization of the pump under varying hydraulic pressures and rotational speeds.

A shaft bearing device for a pump includes an antifriction bearing, which can be connected to an axially displaceable pump shaft. A spring is arranged at the antifriction bearing in such a way, that a spring force can be transmitted to an outer ring of the antifriction bearing by the spring in a mounting condition of the shaft bearing device. A lifting element attached to the pump shaft and a corresponding counter element are separated from each other by the spring force in a starting state and/or in a shutdown state of the pump.

A shaft bearing device for a pump includes an antifriction bearing, which can be connected to an axially displaceable pump shaft. A spring is arranged at the antifriction bearing in such a way, that a spring force can be transmitted to an outer ring of the antifriction bearing by the spring in a mounting condition of the shaft bearing device. A lifting element attached to the pump shaft and a corresponding counter element are separated from each other by the spring force in a starting state and/or in a shutdown state of the pump.

A shaft bearing device for a pump includes an antifriction bearing, which can be connected to an axially displaceable pump shaft. A spring is arranged at the antifriction bearing in such a way, that a spring force can be transmitted to an outer ring of the antifriction bearing by the spring in a mounting condition of the shaft bearing device. A lifting element attached to the pump shaft and a corresponding counter element are separated from each other by the spring force in a starting state and/or in a shutdown state of the pump.

A shaft sealing structure for a rotation shaft, includes a sealing ring having ends formed by removal of its part. The ends abutting each other are continuous in the circumferential direction when the sealing ring is reduced in diameter to a radially inner side. The sealing ring is provided along the circumferential direction of the rotation shaft so as to be contactable with an outer peripheral surface of the rotation shaft. The structure also includes a pressing member configured to be movable between a pressing position and a retracted position; an elastic member configured to bias the pressing member toward the pressing position by elastic force; and a support member configured to support the pressing member at the retracted position against the elastic force, and to allow the pressing member to move to the pressing position at a predetermined temperature.

A pump leakage mitigation device includes one or more clamp arms on an outer surface of a pump that can be driven by a biasing element to seat against a shaft of the pump to seal or reduce fluid flow through a breakdown of the pump. The biasing element engages only at threshold temperatures, such as those associated with breakdown orifice failure when additional sealing may be necessary. Clamp arms of any number and shape can be used to achieve the desired seal and based on the pump geometry. A sealant surface and/or keeping mechanism are useable with the leakage mitigation device to enhance fluid flow blockage throughout a pump failure transient scenario. Pump leakage mitigation devices are installed on an outside of a variety of different pump types and can thus be installed, actuated, manipulated, disengaged, and/or removed without having to destroy or disassemble the pump.

Embodiments include an apparatus and techniques for operating an electromagnetic cartridge seal. Embodiments include operating a cartridge seal in one of a plurality of modes, and receiving a signal at a force applying mechanism of the cartridge seal, the force applying mechanism being coupled to a primary sealing component of the cartridge seal. Embodiments also include controlling the force applying mechanism based at least in part on the received signal.

A pump leakage mitigation device includes one or more clamp arms on an outer surface of a pump that can be driven by a biasing element to seat against a shaft of the pump to seal or reduce fluid flow through a breakdown of the pump. The biasing element engages only at threshold temperatures, such as those associated with breakdown orifice failure when additional sealing may be necessary. Clamp arms of any number and shape can be used to achieve the desired seal and based on the pump geometry. A sealant surface and/or keeping mechanism are useable with the leakage mitigation device to enhance fluid flow blockage throughout a pump failure transient scenario. Pump leakage mitigation devices are installed on an outside of a variety of different pump types and can thus be installed, actuated, manipulated, disengaged, and/or removed without having to destroy or disassemble the pump.

The present invention relates to a passive shutdown sealing device (20) for a reactor coolant pump unit comprising: a split sealing ring (23) having an inactivated position in which a leakage flow is permitted and an activated position in which said ring stops said leakage flow; at least one piston (22) designed to position said split sealing ring (23) in its activated position; locking/unlocking means (25) designed to lock said at least one piston (22) in its inactivated position when the temperature of said locking/unlocking means is below a temperature threshold and to release said at least one piston (22) when the temperature of said locking/unlocking means is above said temperature threshold; elastic means (24) designed to move said at least one piston (22) when said piston is released, so as to position said sealing ring (23) in its activated position.

Realized is a water pump having improved readiness of maintenance. The water pump includes a first unit having a rotatably driven drive shaft and a second unit having a partition wall and configured to circulate cooling medium in association with rotation of the drive shaft. The first unit and the second unit are connectable to and detachable from each other. The partition wall defines an insertion hole for the drive shaft. In this arrangement, there is provided a closing member for closing the insertion hole of the partition wall when the first unit is detached from the second unit.