Provided is a water pump including a lower casing, an upper casing coupled to an upper side of the lower casing to form an impeller accommodating space therein by the coupling with the lower casing and having an inlet communicating with the impeller accommodating space and allowing a fluid to be introduced therethrough and an outlet allowing the fluid to be discharged therethrough, an impeller provided in the impeller accommodating space and including an upper plate and a lower plate arranged to be spaced apart from each other vertically and a plurality of blades arranged and coupled between the upper plate and the lower plate, and a rotor coupled to the impeller and rotated together with the impeller, wherein the upper casing has a spacing recess provided on an inner surface corresponding to an outer circumference of the upper plate of the impeller.

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.

An electric coolant pump is used as an auxiliary water pump in a vehicle. The pump includes radial mounting of the shaft (4) is provided by means of a coolant-lubricated radial sliding bearing (41) arranged between the pump impeller (2) and the rotor (32). A dry-running electric motor (3) with a radially inner stator (31) and a radially outer rotor (32) is accommodated in a motor chamber (13) separated from the pump chamber (10). A shaft seal (5) is between the radial sliding bearing (41) and the motor chamber (13). The rotor (32) is bell-shaped with an inner surface facing the shaft seal (5) and being fixed to the shaft seal (5) to axially overlap with the shaft (4). The motor chamber (13) has an opening to the atmosphere, which is closed by a liquid-tight pressure equalization membrane (6) that is permeable to vapor.

A centrifugal well pump assembly has a non-rotating diffuser between upper and lower rotating impellers. The upper impeller has a cylindrical skirt on a lower side that rotates within a diffuser receptacle. The lower impeller has a cylindrical balance ring on an upper side that rotates within a diffuser cavity. Impeller sleeves are bonded to the skirt and balance ring. Diffuser sleeves are bonded to the diffuser receptacle and cavity. The diffuser sleeves are of a harder material than the impeller sleeves. Each of the impeller sleeves has upper, intermediate and lower circumferential rows of inserts. Each insert has a face flush with the impeller sleeve and is in sliding engagement with one of the diffuser sleeves. The inserts in the intermediate row may be rotationally staggered relative to the inserts in the upper and lower rows to create serpentine flow paths for well fluid leakage.

A diffuser subassembly for use in downhole submersible pump assemblies includes a bearing set for supporting a drive shaft of the pump assemblies. The bearing set includes a sleeve for supporting the drive shaft in upward, downward and radial directions. The sleeve includes a central flange captured axially between a pair of bushings fixed to a diffuser body. Axial loads from the drive shaft may be transferred through the central flange of the sleeve to one or the other of the bushings into the diffuser body to accommodate upward and downward thrust forces. The bushings may be keyed to discourage rotational motion with respect to the diffuser body.

A submersible well fluid pump has diffusers non-rotatably mounted in a pump housing. A drive shaft rotates an impeller between each of the diffusers. A bearing is positioned between and in abutment with two of the diffusers. An annular recess encircles an outer wall of the bearing. A wave spring has undulations with inward protruding indentations in contact with a base of the recess and outward protruding indentations in engagement with an inner wall of the housing. The wave spring is split and radially compressed between the base of the recess and the housing inner wall.

A press-fit thrust bearing system and apparatus. A press-fit thrust bearing for an electric submersible pump includes a protruding band extending around a midsection of a bushing, the protruding band extending inward towards a drive shaft, outward towards a diffuser, or both. When extending outwardly, the band is press-fit into the diffuser to prevent dislodgment of the bushing. A non-rotating guide sleeve extends around the bushing above the protruding band, the guide sleeve interlocking with the protruding band to prevent rotation of the bushing. The guide sleeve includes a projection, the protruding band has a channel and the projection mates with the channel to form the interlock. A pair of flanged, rotatable bearing sleeves extend inwards of the single bushing and are keyed to the drive shaft. The top and bottom faces of the bushing serve as thrust handling surfaces.

An implantable blood pump includes a tube including an inner wall, and wherein during operation of the blood pump, the impeller rotates within the tube and a distance between the inner wall of the tube and the thrust bearing decreases as a speed of the impeller increases.

A technique facilitates operation of a pump, such as a submersible pump in an electric submersible pumping system. The pump has a sequential diffuser and impeller which are operationally engaged via a thrust device. In some embodiments, the diffuser and impeller also are operationally engaged via a front seal. A bypass channel is used to route a flow of fluid from a tip region of the impeller to an inlet region of the impeller without passing through the thrust device during operation of the pump.

An electric submersible pump system can include a shaft; at least one impeller operatively coupled to the shaft; and a bearing assembly that rotatably supports the shaft, where at least one component of the electric submersible pump includes a volumetric composite material that includes polycrystalline diamond material and at least one metallic material.