A centrifugal pump including an outer case; an inner case; a first unit and a second unit placed in fluid communication with each other, each unit including a plurality of impellers; the inner case includes two half-parts joined along a connection plane containing the axis of rotation; a connecting element is placed between the first unit and the second unit, the connecting element is engaged with a last impeller of the first unit and with a last impeller of the second unit.

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.

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.

Disclosed are pumps designed to make priming more efficient and therefore reduce priming time. The disclosed pumps include one or more deflection structures that prevent fluid moving through a diffuser of the pump from continuing in a circular path and instead divert the fluid in a different direction that leads directly to an outlet of the pump. This deflection reduces air bubble accumulation inside the pump while priming and makes it easier for air to escape through the pump outlet. Making it easier for air to escape the pump outlet ultimately allows air to escape the pump faster during priming, reducing back pressure caused by trapped air pockets inside the pump and improving priming performance.

Electric submersible pump and other centrifugal pump stages having non-axisymmetric components and passage contours are disclosed. Such a component can be a shrouded impeller having a non-axisymmetric profile for its hub and/or shroud.

A flow corrector (14) which includes a tubular body (40) with an entry end (42) and an exit end (44), and a plurality of parallel flow passages (54a, 54b, 54c, 54d) between the entry end and the exit end.

An improved parallel flow pump is provided. The improved parallel flow pump includes clearance for tooling, nuts, and bolts, and further provides smoothed, contoured surfaces and one or more turning vanes to improve the top-to-bottom velocity distribution in the discharge manifold into which the pump flows.

The inventive technology, in particular embodiments thereof, may be described as an apparatus (e.g., a pump) that imparts work to and redirects a fluid, and that features an impeller configured to contact and redirect an impeller inflow along a toroidal flowpath to generate an impeller discharge that has both axial and tangential velocity components, where the axial velocity component is substantially 180 degrees relative to a direction of an impeller inflow, in a meridional plane, the apparatus also featuring a diffuser having a diffuser axis that is aligned with an impeller axis of rotation, the diffuser featuring a diffuser outlet annular radial size that is greater than a diffuser inlet annular radial size; and/or curved diffuser vanes established as part of the diffuser, that redirect the impeller discharge so as to reduce the tangential velocity components.

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 spacer, with an upper ring housing and lower ring canopy extending upward and downward, respectively, along the perimeter of the spacer. 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 high-capacity fluid pump comprising a dedicated lubrication system in fluid communication with the pump's drive assembly to reduce wear of internal components within the gearbox, as well as a drive shaft-supported impeller and outboard head to reduce deflection. Moreover, the blades of the outboard head are preferably shaped to decrease the inlet's cross section and stabilize incoming fluid, thereby reducing cavitation, pre-rotation, and turbulent flow at the pump inlet and increasing the overall velocity of incoming fluid.