An inlet valve system (10), as may be used for a cylinder chamber (20) of a compressor, such as a reciprocating compressor, is disclosed. A plurality of inlet valves (250) is movable between an open position and a closed position. The plurality of inlet valves is arranged between an unloader chamber (120) and a cylinder chamber (20) of the compressor. A control valve (270, 270′) is coupled to a controller (300) and is movable between a first position and a second position to close the inlet valves. A check valve (260, 260′) is movable between a first position and a second position to open the inlet valves. The check valve and the control valve are respectively fluidly coupled to a control chamber (252), which is decoupled from any pressure control external to cylinder chamber (20).

Automated control mechanisms and methods for controlling fluid flow in a hemodialysis apparatus are described. The methods can involve a controller receiving information from a pressure sensor in a control chamber of a reciprocating diaphragm-based blood pump and causing the application of a time-varying pressure waveform on a diaphragm of the blood pump during a fill-stroke of the blood pump. The controller can be configured and programmed to monitor a pressure variation in the control chamber measured by the pressure sensor and to compare the measured pressure variation to a pre-determined value. Based on such comparison, the controller can initiate a procedure to pause or stop a dialysate pump of the hemodialysis apparatus if the magnitude of the measured pressure variation deviates from the pre-determined value.

Automated control mechanisms and methods for controlling fluid flow in a hemodialysis apparatus are described. The methods can involve a controller receiving information from a pressure sensor in a control chamber of a reciprocating diaphragm-based blood pump and causing the application of a time-varying pressure waveform on a diaphragm of the blood pump during a fill-stroke of the blood pump. The controller can be configured and programmed to monitor a pressure variation in the control chamber measured by the pressure sensor and to compare the measured pressure variation to a pre-determined value. Based on such comparison, the controller can initiate a procedure to pause or stop a dialysate pump of the hemodialysis apparatus if the magnitude of the measured pressure variation deviates from the pre-determined value.

Oil and gas companies worldwide strive to improve artificial lift efficiencies to minimize environmental footprint and lower operational expense. In order to lower artificial lift costs, the traditional rod pump must be replaced and improved upon. The present invention of the rodless pump and multi-sealing hydraulic sub is an optimized hydraulic pumping system that eliminates rod wear, lowers pump intake pressure, and extends the reserve life of oil and gas wells regardless of casing configuration or depth. Lowering the pump's intake pressure in an oil and gas well by using a positive displacement pump such as the present invention will allow maximum hydrocarbon reserves to be produced with minimal energy consumption to power the pump. The superior surface seals and smaller footprint of the rodless pump eliminate the possibility of surface hydrocarbon leaks, minimizing environmental impact.

Oil and gas companies worldwide strive to improve artificial lift efficiencies to minimize environmental footprint and lower operational expense. In order to lower artificial lift costs, the traditional rod pump must be replaced and improved upon. The present invention of the rodless pump and multi-sealing hydraulic sub is an optimized hydraulic pumping system that eliminates rod wear, lowers pump intake pressure, and extends the reserve life of oil and gas wells regardless of casing configuration or depth. Lowering the pump's intake pressure in an oil and gas well by using a positive displacement pump such as the present invention will allow maximum hydrocarbon reserves to be produced with minimal energy consumption to power the pump. The superior surface seals and smaller footprint of the rodless pump eliminate the possibility of surface hydrocarbon leaks, minimizing environmental impact.

A gas transfer and depressurization system that is configured to transfer gas from a first location to a second location wherein during the transfer of gas the pressure of the first location is reduced. The gas transfer and depressurization system includes a drive chamber having an interior volume with a drive assembly movably disposed therein. A first cylinder and a second cylinder are operably coupled to the drive chamber on opposing sides thereof. The drive assembly includes a drive rod having portions extending into the first cylinder and second cylinder wherein the drive rod has pistons formed on opposing ends thereof. A controller is operably coupled to a compressed air source and is configured to provide compressed air into said drive chamber so as to reciprocally move the drive assembly. Gas blocks and coupling block are additionally present and facilitate flow of gas intermediate the first and second cylinders.

Oil and gas companies worldwide strive to improve artificial lift efficiencies to minimize environmental footprint and lower operational expense. In order to lower artificial lift costs, the traditional rod pump must be replaced and improved upon. The present invention of the rodless pump and multi-sealing hydraulic sub is an optimized hydraulic pumping system that eliminates rod wear, lowers pump intake pressure, and extends the reserve life of oil and gas wells regardless of casing configuration or depth. Lowering the pump's intake pressure in an oil and gas well by using a positive displacement pump such as the present invention will allow maximum hydrocarbon reserves to be produced with minimal energy consumption to power the pump. The superior surface seals and smaller footprint of the rodless pump eliminate the possibility of surface hydrocarbon leaks, minimizing environmental impact.

A pumping cassette including a housing having at least two inlet fluid lines and at least two outlet fluid lines. At least one balancing pod within the housing and in fluid connection with the fluid paths. The balancing pod balances the flow of a first fluid and the flow of a second fluid such that the volume of the first fluid equals the volume of the second fluid. The balancing pod also includes a membrane that forms two balancing chambers. Also included in the cassette is at least two reciprocating pressure displacement membrane pumps. The pumps are within the housing and they pump the fluid from a fluid inlet to a fluid outlet line and pump the second fluid from a fluid inlet to a fluid outlet.

A pumping cassette including a housing having at least two inlet fluid lines and at least two outlet fluid lines. At least one balancing pod within the housing and in fluid connection with the fluid paths. The balancing pod balances the flow of a first fluid and the flow of a second fluid such that the volume of the first fluid equals the volume of the second fluid. The balancing pod also includes a membrane that forms two balancing chambers. Also included in the cassette is at least two reciprocating pressure displacement membrane pumps. The pumps are within the housing and they pump the fluid from a fluid inlet to a fluid outlet line and pump the second fluid from a fluid inlet to a fluid outlet.

A reciprocating piston motor, motor-pump assembly and method for driving a pump. The piston motor includes a pressure medium housing, comprising a first pressure medium chamber having a first pressure medium piston, a second pressure medium chamber having a second pressure medium piston, and a pressure medium control system. The pressure medium control system includes a pressure medium inlet and outlet that are operatively connected to the pressure medium housing. The pressure medium control system is configured to move the pressure medium pistons. A coupling system is provided that is configured to combine the driving forces generated by the first and second pressure medium pistons for driving a fluid pump.