Embodiments are directed toward an engine. In some embodiments, the engine includes a water pump and a balancer shaft. In some embodiments, the water pump has a plain bearing. In some embodiments, plain bearing is supplied with pressurized oil. In some embodiments, the balancer shaft drives the water pump as well as cam shafts.

An electric centrifugal pump includes a water pump shell, a water sealing bearing, a water pump impeller, a spring washer, an inner motor cover, a bearing pedestal, a front rotor bearing, a motor stator, a motor rotor, a shaft of the motor rotor, a rear bearing of the motor rotor, a leading impeller, a leading impeller cover, a water pump driving control panel, a controller cover and a motor shell, and an internal forced cooling system is formed by the water inlet cavity of the water pump, an axial through hole of the shaft of the motor rotor, the leading impeller, a leading impeller cavity of the leading impeller, a spiral overflowing hole of the inner motor cover, a rotor cavity, a spiral overflowing hole of the bearing pedestal and the water pump impeller which are sequentially communicated.

A diffuser for an oil drainback system drain tube includes a flow chamber configured for attachment to an open end of a drain tube, wherein the flow chamber has a side wall and an end wall, and openings in at least the side wall.

A diffuser for an oil drainback system drain tube includes a flow chamber configured for attachment to an open end of a drain tube, wherein the flow chamber has a side wall and an end wall, and openings in at least the side wall.

A bearing cage for a rotor bearing of a turbomolecular pump. The bearing cage includes a plurality of bearing pockets each of which, in use, houses a bearing ball such that the bearing ball operably engages an inner race and an outer race of the rotor bearing. Each bearing pocket of the bearing cage has a primary chamber for housing the bearing ball and each bearing pocket further includes a sump.

A bearing cage for a rotor bearing of a turbomolecular pump. The bearing cage includes a plurality of bearing pockets each of which, in use, houses a bearing ball such that the bearing ball operably engages an inner race and an outer race of the rotor bearing. Each bearing pocket of the bearing cage has a primary chamber for housing the bearing ball and each bearing pocket further includes a sump.

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.

An assembly and a method for lubricating an electric submersible pump assembly disposed in a wellbore are described. The assembly includes a pump to pressurize a wellbore fluid and an electric motor to rotate the pump. The electric motor is lubricated by a dielectric oil. A sensor is coupled to the electric motor to sense a condition of the electric motor and transmit a signal including a value representing the condition. A controller is coupled to the electric motor and the sensor. The controller receives the signal from the sensor, compares the value to a threshold value, determines when the value is greater than the threshold value, and responsive to determining that the value is greater than a threshold value indicating a presence of contaminated dielectric oil, flows a clean dielectric oil from an accumulator to the electric motor to expel the contaminated dielectric oil out of the electric motor.

A compressor system for a cryocooler includes a compressor unit that includes a compressor main body compressing a refrigerant gas of the cryocooler and a liquid-cooled heat exchanger cooling, through heat exchange with a cooling liquid, at least one of the refrigerant gas compressed by the compressor main body and an oil lubricating the compressor main body, a supply line through which the cooling liquid is supplied from a main chiller to the liquid-cooled heat exchanger, a collecting line through which the cooling liquid is collected from the liquid-cooled heat exchanger to the main chiller, and a backup chiller that is provided outside the compressor unit, circulates the cooling liquid to the liquid-cooled heat exchanger in place of or together with the main chiller, and includes a circulation pump and a cooler cooling the cooling liquid on an inlet side or outlet side of the pump.