Abstract: A submersible pumping system for use downhole, wherein the system includes a first pump, a second pump, a recirculation coupling between the first and second pumps, and a recirculation line for directing cooling flow across the pump motor. The pumps and coupling are independent modular items connected together. Optionally, a multi-stage pump may be retrofitted with the coupling for creating a cooling flow.

Abstract: A submersible pumping system for use downhole, wherein the system includes a first pump, a second pump, a recirculation coupling between the first and second pumps, and a recirculation line for directing cooling flow across the pump motor. The pumps and coupling are independent modular items connected together. Optionally, a multi-stage pump may be retrofitted with the coupling for creating a cooling flow.

Abstract: A centrifugal pump has impellers for pumping low flow, high viscous materials. The impellers have high exit angles greater than 30 degrees and preferably greater than 50 degrees. The impellers and diffusers have specific geometry that varies with viscosity. The pump has zones of impellers and diffusers with the exit angles and geometry in the zones differing from the other zones. The exit angles decrease and geometry varies in a downstream direction to account for a lower viscosity occurring due to heat being generated in the pump. One design employs small diameter impellers and high rotational speeds.

Abstract: A method of installing an annular bearing element within a centrifugal pump utilizes a mechanical staking operation. The bearing element locates within a receptacle of a pump stage that is surrounded by a retaining wall. Once the bearing element is located within the retaining wall, the retaining wall is permanently deformed at various points against the bearing element. The bearing element, if of a hard wear resistant metal, may have flats for the circumferentially spaced apart deformations to locate within. The bearing element may be a thrust washer for transmitting downward thrust, or it may be a radial support bearing sleeve.

Abstract: A centrifugal pump has impellers for pumping low flow, high viscous materials. The impellers have high exit angles greater than 30 degrees and preferably greater than 50 degrees. The impellers and diffusers have specific geometry that varies with viscosity. The pump has zones of impellers and diffusers with the exit angles and geometry in the zones differing from the other zones. The exit angles decrease and geometry varies in a downstream direction to account for a lower viscosity occurring due to heat being generated in the pump. One design employs small diameter impellers and high rotational speeds.

Abstract: A method of installing an annular bearing element within a centrifugal pump utilizes a mechanical staking operation. The bearing element locates within a receptacle of a pump stage that is surrounded by a retaining wall. Once the bearing element is located within the retaining wall, the retaining wall is permanently deformed at various points against the bearing element. The bearing element, if of a hard wear resistant metal, may have flats for the circumferentially spaced apart deformations to locate within. The bearing element may be a thrust washer for transmitting downward thrust, or it may be a radial support bearing sleeve.

Abstract: A submersible pump assembly has a pump and a valve connected to the outlet of the pump. An outlet of the valve is connected to a riser. A valve member in the valve housing is vertically movable between a pumping position and a priming position, the valve member being biased toward the priming position. A priming conduit connects the outlet of the valve housing to the inlet of the pump for directing well fluids flowing through the conduit into an intake of the pump for re-priming the pump. When the pump is pumping well fluid, the valve member is moved to the pumping position by the fluid pressure, well fluids flowing from the inlet of the valve housing to the outlet of the valve housing but not through the priming conduit. When pumping ceases, the valve member returns to the priming position, well fluids flowing through the priming conduit for re-priming the pump.

Abstract: A submersible pump assembly has a pump and a valve connected to the outlet of the pump. An outlet of the valve is connected to a riser. A valve member in the valve housing is vertically movable between a pumping position and a priming position, the valve member being biased toward the priming position. A priming conduit connects the outlet of the valve housing to the inlet of the pump for directing well fluids flowing through the conduit into an intake of the pump for re-priming the pump. When the pump is pumping well fluid, the valve member is moved to the pumping position by the fluid pressure, well fluids flowing from the inlet of the valve housing to the outlet of the valve housing but not through the priming conduit. When pumping ceases, the valve member returns to the priming position, well fluids flowing through the priming conduit for re-priming the pump.

Abstract: A centrifugal pump has impellers for pumping low flow, high viscous materials. The impellers have high exit angles greater than 30 degrees and preferably greater than 50 degrees. The impellers and diffusers have specific geometry that varies with viscosity. The pump has zones of impellers and diffusers with the exit angles and geometry in the zones differing from the other zones. The exit angles decrease and geometry varies in a downstream direction to account for a lower viscosity occurring due to heat being generated in the pump. One design employs small diameter impellers and high rotational speeds.

Abstract: A fluid pump has an integral filament-wound housing bonded to internal parts of the pump. The pump housing is made of composite material (such as fiberglass strands coated with epoxy resin) wound about an adapter, pumping members and an output flange. Once hardened, the housing, adapter, pumping members and output flange are permanently bonded together to form a unitary structure. Pump efficiency is greatly enhanced because the pump housing forms a fluid-tight seal between (a) pumping members and (b) between pumping members and the housing and further prevents rotation of the pumping members in response to torque forces during pump operation.

Abstract: The invention is an improvement in a centrifugal pump of the type having two or more pumping stages. Each stage includes a stationary diffuser and a companion rotatable impeller with a wear ring set arranged between the diffuser and impeller of each stage. The improvement includes a bearing ring formed of a hard material, preferably harder than sand. A second bearing ring is formed of a resilient material in thrust-absorbing, sealing contact with the first ring whereby grit or sand may be lodged between the rings without substantially impairing such contact of the rings with one another. In the first embodiment, the bearing rings perform a sealing function as well as absorb axial thrust. In the second embodiment, a primary sealing function is provided by a separate annular disc with which the impeller is in contact.