A downhole-type device includes an electric machine. The electric machine includes an electrical rotor configured to couple with a device to drive or be driven by the electric machine. An electrical stator surrounds the electric rotor. The electric stator includes a seal configured to isolate stator windings from an outside, downhole environment. An inner surface of the seal and an outer surface of the electric rotor define an annulus exposed to the outside environment. A bearing couples the electric rotor to the electric stator. A lubrication system is fluidically coupled to the downhole-type device. The lubrication system includes a topside pressure pump and a downhole-type distribution manifold configured to be used within a wellbore. The distribution manifold is fluidically connected to the topside pressure pump and the bearing to receive a flow of lubricant from the topside pressure pump.

A well pump includes a plurality of diffusers, wherein each diffuser comprises a first threaded coupling on one longitudinal end and a second threaded coupling on an opposed longitudinal end. An impeller is disposed in each diffuser. The plurality of diffusers are coupled end to end to form a pump housing, in which the first threaded coupling on one diffuser is threadedly engaged to the second threaded coupling on adjacent diffuser.

A non-clogging pump includes a pump casing and an impeller that includes a main plate portion and a vane portion, in which the main plate portion includes a main plate protrusion portion that protrudes in a counter-inflow direction, the vane portion includes a first end face and a second end face and is connected to the main plate protrusion portion at an inner periphery-side end portion, and an inner peripheral wall that forms the suction port of the pump casing includes a suction port protrusion portion that is provided at a portion in a rotation direction of the rotating shaft, is disposed along the second end face with a gap from the second end face, and protrudes toward a center side of the suction port.

An electric submersible pump includes a pump, an electric motor that is coupled to the pump by a rotatable shaft, a seal section that is positioned between the pump and the electric motor. The seal section contains an additive and a motor oil for the electric motor. The additive includes one or more superabsorbent polymers or imidate salts to contact the motor oil and to react with a wellbore fluid from a wellbore to prevent premature failure of the electric submersible pump from the wellbore fluid contamination of the motor oil.

An assembly structure of a multi-stage impeller and wheel housing for use in a submersible pump that includes a connecting seat having a drainage channel, shaft, intermediate unit which has a wheel housing, inner guide cover, and impeller. The wheel housing has a central partition plate, with an upper ring housing and lower ring canopy extending upward and downward, respectively, along the perimeter of the central partition plate. The intermediate unit has the upper ring housing connected to the canopy of the connecting seat by a swivel snap structure. A bottom unit has a bottom impeller and bottom wheel housing, which has a water suction port, a bottom plate and a bottom ring housing that extends upward along the perimeter of the bottom plate. A bottom ring canopy of an intermediate unit is connected by a rotating snap structure, and the bottom ring housing is pressed by a sealing ring.

A sump pump system enables automatic determination and utilization of frequencies for mechanical shakers for sump pumps. These techniques may be implemented to detect a fault (e.g., a stuck impeller) with a sump pump and to identify a desirable frequency at which a mechanical shaker for the sump pump should vibrate to correct the fault.

A fluid machine includes: a shaft portion; a shroud surrounding the shaft portion and including an inside surface that forms a flow path-forming surface defining a flow path with the shaft portion; a first propeller rotatably provided in the flow path; a second propeller rotatably provided on a downstream side of the first propeller in the flow path; and a motor including a rotor that is fixed to an outer circumferential portion of the second propeller and that is accommodated in the shroud, and a stator that surrounds the rotor via a clearance and that is fixed in the shroud. A portion of the flow path-forming surface on a downstream side of the second propeller decreases in diameter toward the downstream side, and the shroud includes an inlet flow path that is open at a portion between the first propeller and the second propeller of the flow path-forming surface.

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 fluid machine includes: a shaft portion; a shroud surrounding the shaft portion and including an inside surface that forms a flow path-forming surface defining a flow path with the shaft portion; a first propeller rotatably provided in the flow path; a second propeller rotatably provided on a downstream side of the first propeller in the flow path; and a motor including a rotor that is fixed to an outer circumferential portion of the second propeller and that is accommodated in the shroud, and a stator that surrounds the rotor via a clearance and that is fixed in the shroud. A portion of the flow path-forming surface on a downstream side of the second propeller decreases in diameter toward the downstream side, and the shroud includes an inlet flow path that is open at a portion between the first propeller and the second propeller of the flow path-forming surface.

An oil field pump is installed within a pipe that connects to an oil field, and feeds accumulated extraction oil in a predetermined direction, the oil filed pump including a rotor with an internal flow path for the extraction oil, a stator installed on the outer circumference of the rotor, a thrust bearing that supports the axial weight of the rotor and the stator, a supply pipe that supplies a portion of the extraction oil in the flow path to the thrust bearing, and a filter that is installed at further upstream on the flow path than the supply pipe along the flow direction of the extraction oil, and traps foreign matter.