A hydraulic pump assembly having a main pump, a charge pump and an auxiliary pump driven by a single shaft is provided. A pair of hydraulic porting members cooperates to feed and distribute hydraulic fluid between the three pump units, and a single inlet may be used to provide hydraulic fluid to the charge pump and the auxiliary pump.

Lifting device (10) for vertically lifting liquids, where the lifting device (10) comprises: a lifting line arrangement (18) for guiding a liquid from an open lower reservoir (16) to an upper reservoir (14); a lowering line arrangement (20) for guiding the liquid from the upper reservoir (14) to the lower reservoir (16); a pressure converter (12) with an actuating member (36), the pressure converter (12) being configured to convert a liquid pressure in the lowering line arrangement (20) into a liquid pressure in the lifting line arrangement (18) by means of a substantially linear movement of the actuating member (36); and a pump member (38) for pumping the liquid in the lifting line arrangement (18) towards the upper reservoir (14) and/or for pumping the liquid in the lowering line arrangement (20) towards the pressure converter (12).

Lifting device (10) for vertically lifting liquids, where the lifting device (10) comprises: a lifting line arrangement (18) for guiding a liquid from an open lower reservoir (16) to an upper reservoir (14); a lowering line arrangement (20) for guiding the liquid from the upper reservoir (14) to the lower reservoir (16); a pressure converter (12) with an actuating member (36), the pressure converter (12) being configured to convert a liquid pressure in the lowering line arrangement (20) into a liquid pressure in the lifting line arrangement (18) by means of a substantially linear movement of the actuating member (36); and a pump member (38) for pumping the liquid in the lifting line arrangement (18) towards the upper reservoir (14) and/or for pumping the liquid in the lowering line arrangement (20) towards the pressure converter (12).

A pump is formed by a housing (10) having an inlet (11) and an outlet (12) for a fluid. The housing (10) contains a rotator (13) provided with at least one surface recess (17a, 17b, 17c, 17d) that forms with an interior surface of the rotor a chamber (18a, 18b, 18c, 18d) that, on rotation of the rotor (13), conveys fluid from the inlet (11) to the outlet (12). A flexible seal (23) is provided on or as part of the housing (10) and is located between the inlet (11) to the outlet (12) to engage the rotor (13) to prevent fluid passing from the outlet (12) to the inlet (11). A second inlet (16) is provided leading to the outlet (12) for the supply to the outlet (12) of a second fluid and the second inlet (16) also supplies the second fluid to the back of the seal (23) to urge the seal (23) against the rotor (13).

A pump is formed by a housing (10) having an inlet (11) and an outlet (12) for a fluid. The housing (10) contains a rotator (13) provided with at least one surface recess (17a, 17b, 17c, 17d) that forms with an interior surface of the rotor a chamber (18a, 18b, 18c, 18d) that, on rotation of the rotor (13), conveys fluid from the inlet (11) to the outlet (12). A flexible seal (23) is provided on or as part of the housing (10) and is located between the inlet (11) to the outlet (12) to engage the rotor (13) to prevent fluid passing from the outlet (12) to the inlet (11). A second inlet (16) is provided leading to the outlet (12) for the supply to the outlet (12) of a second fluid and the second inlet (16) also supplies the second fluid to the back of the seal (23) to urge the seal (23) against the rotor (13).

A vacuum pump system includes a secondary pumping mechanism incorporated into a stationary portion of a scroll pump. The stationary portion includes the stationary plate scroll of the scroll pump and defines a gas passageway in which the secondary pumping mechanism is disposed. The gas passageway is connected to a gas flow path through the scroll pump at a location upstream of an exhaust check valve of the scroll pump. The secondary pumping mechanism is displaceable within the gas passageway to draw residual gas in the compression stage upstream of the check valve into the gas passageway, and may pump the residual gas back out through the exhaust check valve, to evacuate residual gas from the compression stage.

A vacuum pump system includes a secondary pumping mechanism incorporated into a stationary portion of a scroll pump. The stationary portion includes the stationary plate scroll of the scroll pump and defines a gas passageway in which the secondary pumping mechanism is disposed. The gas passageway is connected to a gas flow path through the scroll pump at a location upstream of an exhaust check valve of the scroll pump. The secondary pumping mechanism is displaceable within the gas passageway to draw residual gas in the compression stage upstream of the check valve into the gas passageway, and may pump the residual gas back out through the exhaust check valve, to evacuate residual gas from the compression stage.

A hydraulic circuit includes a pump in fluid communication with a reservoir containing a liquid to be pumped. The pump includes an inlet and an outlet. The hydraulic circuit also includes a venturi pump in fluid communication with the reservoir and with the outlet of the pump, and an injection valve including a cooling feature. The injection valve is in fluid communication with the outlet of the pump, and is configured to dispense liquid supplied to the injection valve by the pump. The cooling feature is in fluid communication with the venturi pump. The pump is configured to produce a first flow of liquid, and the hydraulic circuit is configured to supply a first portion of the first flow of liquid to the injection valve for dispensing by the injection valve and a second portion of the first flow of liquid to the venturi pump.

A hydraulic pump assembly having a main pump, a charge pump and an auxiliary pump driven by a single shaft is provided. A pair of hydraulic porting members cooperates to feed and distribute hydraulic fluid between the three pump units, and a single inlet may be used to provide hydraulic fluid to the charge pump and the auxiliary pump.

A submersible pumping system has an electric motor, a rotary hydraulic pump driven by the electric motor, and a linear hydraulic pump that is configured to move a production fluid. The rotary hydraulic pump produces a pressurized working fluid that drives the linear hydraulic pump. In another aspect, a method is disclosed for controlling the temperature of an electric motor within a submersible pumping system disposed in a wellbore. The method includes the steps of circulating motor lubricant through a hydraulically driven production pump to reduce the temperature of the motor lubricant.