The multi-compressor system (7) has a plurality of parallelly coupled compressors (8); inlet connection lines (15) each connected to a refrigerant suction fitting of a respective compressor (8); outlet connection lines (17) each connected to a refrigerant discharge fitting of a respective compressor (8); a common oil balancing line (18) and balancing connection lines (19) each connecting the common oil balancing line (18) to an oil balancing connection (21) of a respective compressor (8); and spring-loaded normally-open valves (25) each being arranged within a respective balancing connection line (19) or within an oil balancing connection (21) of a respective compressor (8) and each being configured to close when a pressure difference between a pressure prevailing in the low pressure volume of the respective compressor (8) and a pressure prevailing in the common oil balancing line (18) reaches a predetermined value.

A fuel system for a turbomachine includes a fuel tank and a first fuel line in fluid communication with the fuel tank and one or more fuel injectors. The first fuel line includes a main fuel pump disposed on the first fuel line, and an electric metering system disposed on the first fuel line downstream of the main fuel pump configured for starting the turbomachine and metering fuel to the fuel injectors.

An electric oil pump includes a pump housing provided with an a first cavity and a second cavity; a first rotor assembly disposed in the first cavity; a stator assembly and a second rotor assembly that are disposed in the second cavity; an electric control board assembly; an isolating member, where the stator assembly is disposed at a first side of the isolating member, the electric control board assembly is disposed at a second side of the isolating member; and a wiring terminal fixedly connected to the isolating member; where a connecting position between the wiring terminal and the isolating member is sealed and a connecting position between the isolating member and the pump housing is sealed. The electric oil pump can prevent working medium from affecting the performance of the electric control board assembly.

A rotary compressor is provided for which a vane slot is formed in each cylinder, a suction port is disposed at one side of the vane slot in a circumferential direction with a partition wall interposed therebetween, and at least one elastic portion is formed in a penetrated or recessed manner at at least one circumferential side surface of the partition wall or between circumferential side surfaces. Accordingly, an elastic strain of the partition wall may increase to reduce friction loss between the vane slot and a vane, a sealing distance may be secured between axial side surfaces of the partition wall to prevent refrigerant leakage between the vane slot and the suction port, an amount of oil or refrigerant stored between the vane and the vane slot may be increased by virtue of the at least one elastic portion formed on an inner surface of the vane slot defining the partition wall, thereby improving lubricity.

A method for pumping a liquid-gas mixture into a subsurface well includes introducing gas into a liquid at a first pressure to generate a mixture. The mixture is pumped through a first positive displacement pump to a second pressure greater than the first pressure. The mixture at the second pressure is pumped through at least a second positive displacement pump to a third pressure greater than the second pressure. The mixture is moved into the subsurface well at at least the third pressure.

A method for pumping a liquid-gas mixture into a subsurface well includes introducing gas into a liquid at a first pressure to generate a mixture. The mixture is pumped through a first positive displacement pump to a second pressure greater than the first pressure. The mixture at the second pressure is pumped through at least a second positive displacement pump to a third pressure greater than the second pressure. The mixture is moved into the subsurface well at at least the third pressure.

A pump device, that supplies a liquid reserved in a reservoir to a first liquid supply destination and a second liquid supply destination, includes: a first pump whose suction port and discharge port are not switched between at forward rotation and at reverse rotation; a second pump whose suction port and discharge port are switched each other between at forward rotation and at reverse rotation; a power source that optionally switches a rotation direction of the power source; a shaft member that is rotated by a driving force from the power source; and a control device that controls at least a rotation direction of the power source. Further, the first pump and the second pump are provided on the shaft member, the first pump is connected to the first liquid supply destination, and the second pump is connected to the second liquid supply destination.

An electric pump system and method of operating the same involves pumping a fluid through a fluid passageway defined in a mechanical pump from a pump inlet to a hollow shaft of a motor, through the hollow shaft to an internal motor cavity defined by a housing of the motor, and through another fluid passageway defined in the motor housing and mechanical pump that leads to a pump outlet. The system and method further involve pumping the fluid through another fluid passageway defined in the mechanical pump from yet another pump inlet to the pump outlet. The temperature of fluid exiting the hollow shaft can be assessed and used by an electronic control unit (ECU) of the electric pump system to control the same. The electric pump system can be part of a cooling and lubrication system for an electric vehicle transmission, gearbox, differential or transfer case, for example.

A compressor system (10) and an intake pipe (300) used for the compressor system (10), wherein the intake pipe (300) comprises: a lubricant separator (310), which is configured to separate a lubricant which is in a compression fluid flowing through the intake pipe (300); and a first lubricant supply pipe (340), which is configured to supply the separated lubricant to a first compressor (100) or a second compressor (200) in the compressor system (10).

A method for pumping a liquid-gas mixture into a subsurface well includes introducing gas into a liquid at a first pressure to generate a mixture. The mixture is pumped through a first positive displacement pump to a second pressure greater than the first pressure. The mixture at the second pressure is pumped through at least a second positive displacement pump to a third pressure greater than the second pressure. The mixture is moved into the subsurface well at at least the third pressure.