A rotary oscillating sub-assembly for positive displacement pumping of a fluid, said sub-assembly comprising: a hollow body defining a cavity having a wall with two ducts passing therethrough; a piston co-operating with said cavity to define a working chamber and including a channel that opens out longitudinally into said working chamber, said piston being movable angularly so as to put said working chamber into fluid-flow communication with one, then none, then the other of said ducts, and being movable in longitudinal translation to reciprocate so as to cause the volume of said working chamber to vary and successively suck in and then discharge said fluid, said piston carrying a sealing gasket that is formed of at least a sealing ring, a sealing half-ring, and at least one sealing strip that longitudinally connects said sealing ring to said sealing half-ring.

The invention relates to a rotary lobe pump including a pump housing with a pump chamber, an inlet opening and an outlet opening. A first multi-lobed rotary piston is rotably mounted around a first axis in the pump chamber. A second multi-lobed rotary piston is rotably mounted around a second axis in the pump chamber and meshes with the first rotary piston. The first and second rotary pistons are rotated by a drive unit to create a fluid flow from the inlet opening to the outlet opening. The drive unit includes a first electric drive motor mechanically coupled with the first rotary piston and a second electric drive motor mechanically coupled with the second rotary piston.

The invention relates to a rotary lobe pump including a pump housing with a pump chamber, an inlet opening and an outlet opening. A first multi-lobed rotary piston is rotably mounted around a first axis in the pump chamber. A second multi-lobed rotary piston is rotably mounted around a second axis in the pump chamber and meshes with the first rotary piston. The first and second rotary pistons are rotated by a drive unit to create a fluid flow from the inlet opening to the outlet opening. The drive unit includes a first electric drive motor mechanically coupled with the first rotary piston and a second electric drive motor mechanically coupled with the second rotary piston.

The invention relates to system and method for desanding an oil well that includes a fluidizing device (TORE), connected to a downhole pump that connects to a production tubing such that a supply duct is connected to the discharge of the pump and a discharge duct is connected to the suction of the pump. Embodiments include a pressure balance transition device between the TORE and the pump and/or a flow splitting device in the production tubing after the discharge of the pump. Other embodiments relate to a system and method for desanding an oil well in which a fluidizing unit is connected to a pump such that the supply duct is connected to an opening in the pump body or pump rotor and a discharge duct is connected to the suction of the pump. If connected to the rotor, the supply duct is integral to the pump rotor.

The invention relates to system and method for desanding an oil well that includes a fluidizing device (TORE), connected to a downhole pump that connects to a production tubing such that a supply duct is connected to the discharge of the pump and a discharge duct is connected to the suction of the pump. Embodiments include a pressure balance transition device between the TORE and the pump and/or a flow splitting device in the production tubing after the discharge of the pump. Other embodiments relate to a system and method for desanding an oil well in which a fluidizing unit is connected to a pump such that the supply duct is connected to an opening in the pump body or pump rotor and a discharge duct is connected to the suction of the pump. If connected to the rotor, the supply duct is integral to the pump rotor.

An electric submersible progressive cavity pump assembly is disclosed, which includes an electric motor, a progressive cavity pump, a transmission rotatable by the motor, and a torque isolator coupled between the transmission and the progressive cavity pump, where the torque isolator includes resilient members which accommodate sudden changes in torque.

A vehicle including a housing supported on a framework member of the vehicle via a supporting member, a liquid medium supply unit fixed to the housing and driven by a motor to supply a liquid medium to a cooled or lubricated portion, and a first atmosphere communicating mechanism that establishes a communication between an inside of a motor portion of the liquid medium supply unit and atmosphere, the first atmosphere communicating mechanism including a volumetric member that is disposed apart from the liquid medium supply unit in a position higher than the liquid medium supply unit, that has a predetermined volumetric space, and that is fixed to the housing.

An electrical submersible pump assembly has a thrust bearing mechanism with first and second thrust runners axially and rotationally secured to the shaft and located within a housing. First and second thrust receiving structures are rigidly mounted in the housing to receive thrust from the first and second thrust transferring devices. A deflectable member located in the first thrust transfer thrust device decreases in axial thickness in response to thrust of a selected level. The second thrust transfer thrust device has an axial length less than an axial distance from the second thrust receiving structure to the second thrust runner, defining an initial axial gap. During operation of the pump, the shaft and the first and second thrust runners move axially a limited extent, closing the gap and transferring thrust from the second thrust transfer device to the second thrust receiving structure.

A submersible pump assembly has a seal section between the motor and the well fluid pump, the seal section having a housing, a shaft and a thrust bearing unit. The thrust bearing unit includes a thrust runner mounted to the shaft that rotates against a thrust bearing base fixed in the housing. An annular, metal thrust runner wave spring has an inner diameter surface in contact with the shaft and an outer diameter surface in contact with the runner bore. The wave spring has a transverse width between the inner diameter surface and the outer diameter surface that is elastically deflectable, exerting an inward bias force against the shaft and an outward bias force against the runner bore.

A lubricant vane pump for providing a pressurized lubricant for an internal combustion engine includes a pump housing, a pump chamber, a shiftable control ring comprising a pressure-relief-valve, a pump rotor, a pretensioning element which pushes the control ring into a high pumping volume position, a control chamber, and a pump outlet cavity fluidically connected to the control chamber. The pump chamber comprises pump compartments which rotate from a charge to discharge zone. The control ring envelops the pump chamber. The pump rotor comprises radially slidable vanes which rotate in the control ring to provide the pump chamber with the pump compartments. A high lubricant pressure in the control chamber moves the control ring into a low pumping volume direction against the pretensioning element. The pressure-relief-valve of the control ring connects or disconnects the control chamber with one of the pump compartments between the charge zone and the discharge zone.