A multistage pump with axial thrust optimization is disclosed includes a pump discharge nozzle and a bypass system coupled to the pump discharge nozzle. The bypass system includes a throttle valve operatively coupled to the pump discharge nozzle, and a bypass line provided at the multistage pump. The bypass line is conducts flow from the throttle valve to a clearance gap of an axial thrust balancing arrangement. The throttle valve may be actuated to adjust a balancing flow through the bypass line such that pressure at the clearance gap is adjusted to increase and decrease fluid pressure at the clearance gap to balance axial thrust at different operating states of the multistage pump.

A fluid rotor and a fluid stator. The fluid stator surrounds the fluid rotor. The fluid stator has an intake end and a discharge end. The fluid stator is shaped to be inserted into a wellbore. A shaft passes through a rotational axis of the fluid rotor. The shaft is attached to the fluid rotor to rotate in union with the fluid rotor. The shaft defines a central fluid passage that extends from the intake end of the fluid rotor to the discharge end of the fluid rotor. A balance piston surrounds the shaft. The balance piston extends from an outer surface of the shaft to an inner surface of the fluid stator. The balance piston is positioned at the intake end.

A process fluid lubricated pump includes a housing with an inlet to receive the fluid, and an outlet to discharge the fluid, a shaft extending from a drive end to a non-drive end and rotatable about an axial direction, the drive end of the shaft arranged outside the housing, a hydraulic unit including impellers mounted on the shaft, a collection chamber to collect leaking process fluid, the collection chamber comprising an exit, through which the shaft passes, and an exit to discharge the process fluid, and a throttle device arranged between the hydraulic unit and the collection chamber, the throttle device comprising a stationary throttle part having first and second axial faces delimiting the stationary throttle part, the first axial face facing the collection chamber, and the throttle device including a throttle gap surrounding the shaft and extending from the first axial face to the second axial face.

The balancing system has a balancing body to be mounted on a rotor of a turbomachine and a sealing ring to be mounted on a stator of the turbomachine; the sealing ring is arranged around the balancing body so that the balancing body can rotate about a rotation axis, thus there is a clearance between the body and the ring; furthermore, there is an arrangement for changing an axial position of the sealing ring during operation of the turbomachine so that the clearance can be adjusted. The possibility of adjusting clearance during operation of the turbomachine, such balancing system provides a good balancing action with a small leakage and a small risk of mechanical interference at any time during operation of the turbomachine.

A rotary pump for conveying a fluid, includes a pump housing, a pump shaft, a hydraulic unit, a mechanical seal, and a stator. The hydraulic unit conveys and pressurizes the fluid, includes an impeller fixedly mounted on the pump shaft, and during operation generates an axial thrust to act on the pump shaft. The mechanical seal seals the pump shaft and includes a rotor connected to the pump shaft in a torque proof manner. The stator is stationary with respect to the pump housing. The mechanical seal is arranged between the hydraulic unit and an end of the pump shaft, and is a balancing device configured to generate an axial force on the pump shaft during operation, with the axial force configured to counteract the axial thrust.

A first fluid rotor that has a first fluid intake end and a first fluid discharge end. The first fluid rotor includes a shaft and an impeller. A second fluid rotor that has a second fluid intake end and a second fluid discharge end. The second fluid rotor is rotatably coupled to the first fluid rotor to rotate in unison with the first fluid rotor along a shared rotational axis. The first fluid intake end and the second fluid intake end are facing opposite directions. The second fluid rotor includes a second shaft and a second impeller. A first fluid stator surrounds the first fluid rotor. The first fluid stator is aligned along the rotational axis. The first fluid rotor and the first fluid stator form a first fluid stage. A second fluid stator surrounds the second fluid rotor. The second fluid stator is aligned along the rotational axis. The second fluid stator and the second fluid rotor form a second fluid stage. A flow crossover sub is positioned between the first fluid stage and the second fluid stage. The flow crossover sub defines flow passages that fluidically connect the first fluid stage and the second fluid stage. An outer housing surrounds the first fluid stator, the second fluid stator, and the flow crossover sub.

A rotary machine according to at least one embodiment is configured such that, in a region on an opposite side to a thrust collar across a key in an axial direction, a defective portion is provided on one of an outer circumferential surface of a shaft, or a surface of the shaft along a radial direction or a surface of a holding member along the radial direction, or at least a part of a section having the surface along the radial direction is formed by a material having a Young's modulus lower than a Young's modulus in another section.

A rocket engine propulsion system having improved engine performance is described herein. The rocket engine propulsion system includes multiple axial counterbalances to reduce or eliminate axial thrust exerted on components of a turbopump. The axial counterbalances can allow for a larger range of axial thrust forces while coupling this ability to a rotational speed (e.g., rotations per minute, or RPM) of a shaft. The axial counterbalances include protrusions that extend circumferentially around a shaft that mate with protrusions on swing arms. The swing arms are rotatably attached to a bracket which is constrained by a static support.

A liquid pressurizing apparatus, comprises a tank provided on a device installation surface for storing liquid so that a fluid level is located above the device installation surface; and a vertical pump including a suction port connected to the tank, multi-stage impellers arranged in a vertical direction, and a discharge port for discharging the liquid passing through the multi-stage impellers. The multi-stage impellers include a first stage impeller positioned at the lowest part of the multi-stage impellers and being configured such that the liquid from the suction port flows into the first stage impeller. The first stage impeller is disposed below the device installation surface.

A centrifugal pump includes a radial impeller surrounded by a housing. The housing has a channel associated with a front side space between a cover of the impeller and the casing. Flow is led through the channel from a pressure region of the pump to a radial gap at a suction region of the pump. The flow in the channel reduces angular momentum and results in an increase in pressure in the front side space which acts of in the cover side of the impeller to offset axial force from a rear side of the impeller.