A main pump shaft seal water injection system of a nuclear power plant includes a jet pump, a high pressure cooler, a hydrocyclone, valves and a main connection pipeline outside of a main pump, and an auxiliary pump and an internal flow path inside the main pump. Inner and outer flow paths of the main pump are connected with a shaft seal water injection hole and a high temperature water drainage hole. The main connection pipeline is connected between an upper filling water pipeline and a shaft seal water injection hole. A bypass pipeline connected with the jet pump, the high pressure cooler and the hydrocyclone, the main connection pipeline is provided with a normally open main pipeline isolating valve. The bypass pipeline allows low temperature upper filling water in the RCV system to enter the shaft seal water injection hole of the main flange directly.

A stuffing box for sealing a top opening of a vertical pump, including: a housing with a vertical tube for rotatably disposing a shaft of the vertical pump, an annular bearing that: divides the vertical tube in a lower half and an upper half, and fills an annular space between an inner wall of the vertical tube and the shaft, such that as less fluid as possible passes from the lower half through the annular bearing to the upper half, an outlet pipe for discharging the fluid passing through the annular bearing.

One or more techniques and/or systems are disclosed for mitigating fluid loss or leakage from a fluid pump with a rotating shaft driving a pumping mechanism. A seal gland component can have two or more internal seals formed by two or more seal components, such as O-rings, that create one or more chambers that act as a lubricant/barrier fluid reservoir to provide for reduced friction and mitigate release of gaseous emissions. Further, the seal gland component can be a retrofit on an existing shaft to provide for greater life and efficiency as compared to the existing packing gland or other sealing components. Further, the one or more internal seals can be arranged within the seal gland in an asymmetrical manner such that the seal gland can be removed from a shaft, rotated, and reinstalled with the internal seals contacting a different position on the surface of the shaft.

The present invention is directed to a fluid sealing member and a motor for preventing or reducing chances of fluids and/or substances or products from entering the motor chamber or cavity of a motor and causing damage to the motor's internal components and/or causing the motor to make undesirable noises or sounds. The present invention is also directed to a motor having a fluid sealing member, and to a fluid pump having a fluid sealing member. The present invention is further directed to a fluid pump that comprises a jet assembly and a motor assembly, which comprises a motor. The fluid pump may further comprise one, some or all of the following: a fluid sealing member, a mounting housing member or coupling device, a gasket or seal, a liner (when a liner is not already provided or present), and a driven magnetic disc assembly having a magnetic pole array.

A molten metal pump having a base member defining a pumping chamber is provided. The pumping chamber includes an opening in each of a top surface and a bottom surface of the base member. An impeller is disposed in the pumping chamber and is configured to draw molten metal through the opening in the bottom surface and expel the molten metal through an outlet in the base member. A flow diverter is disposed above the opening in the top surface.

A seal structure of a drive device is provided which includes a case in which a motor chamber for accommodating an electric motor and a gear chamber for accommodating a gear mechanism are located adjacent to each other, a partition that separates the motor chamber and the gear chamber, a bearing that supports a rotating shaft, a seal part that seals between the rotating shaft and the partition, a lubricating oil that lubricates the gear mechanism, and a coolant that cools the electric motor, and also includes a first bearing on the motor chamber side, a second bearing on the gear chamber side, a first seal part on the motor chamber side, a second seal part on the gear chamber side, and at least the second seal part of the first seal part and the second seal part is provided between the first bearing and the second bearing.

A high-lift shielded permanent magnet multistage water pump includes a pump shell, a motor assembly and an impeller. The motor assembly includes a motor barrel, a stator, a rotor and a rotor shaft. The pump shell is sleeved on an outside of motor barrel. An upper and a lower connection base for fixing the motor barrel is provided in the pump shell. A waterway cavity is formed between the pump shell and motor barrel. An upper and a lower impeller cavities are respectively formed at an upper and a lower ends of the pump shell. The lower impeller cavity, water passing cavity and upper impeller cavity are in sequential fluid communication. Both ends of the rotor shaft with an axel provided on pass through the upper and the lower connection bases respectively. The impeller is a multistage structure and mounted on the axle at both ends respectively.

An electrical submersible well pump assembly has shaft couplings. One of the couplings has a lower hub that rotates in unison with the motor shaft and an upper hub that rotates in unison with the pump shaft. A helical spring clutch engages both hubs when the motor shaft is being driven by the motor. Ceasing driving rotation of the motor shaft causes the spring clutch to disengage from the upper hub, enabling the pump shaft to rotate the upper hub without rotating the lower hub.

An integrated pressurized pump shaft seal assembly for a submersible rotary fluid pump comprises an oil reservoir having a pressure equal or less than the ambient pressure external fluids surrounding the casing, the oil reservoir feeding an oil pump impeller that is mountable onto, so as to be rotated by, the rotary fluid pump shaft. The impeller is a radial hole impeller in fluid communication with an adjacent diffusion element comprising an internal diffusion bore in fluid communication with an axially vertical spiral volute diffusion chamber located between inner and outer walls of a mechanical seal housing. The centrifugal oil pump impeller pumps oil from the oil reservoir to the seal chamber through the diffusion element and the internal volute diffusion element so as to increase a pressure within the seal chamber to a positive pressure above the ambient pressure of the external fluids surrounding the pump housing.

An integrated pressurized pump shaft seal assembly for a submersible rotary fluid pump comprises an oil reservoir having a pressure equal to or less than the ambient pressure external fluids surrounding the casing, the oil reservoir feeding an oil pump impeller that is mountable onto, so as to be rotated by, the rotary fluid pump shaft. The oil pump impeller is in fluid communication with an internal volute diffusion element integrated into a pump component. The centrifugal oil pump impeller pumps oil from the oil reservoir to the seal chamber through the internal volute diffusion element so as to increase a pressure within the seal chamber to a positive pressure above the ambient pressure of the external fluids surrounding the pump housing.