Abstract: The compressor arrangement comprises a main compressor having a suction side, a delivery side, and at least one dry gas seal. The dry gas seal is fluidly coupled to a sealing gas feed circuit adapted to receive sealing gas from the delivery side of the main compressor and feed the sealing gas to the at least one dry gas seal. An auxiliary compressor unit is further provided, including a sealing gas inlet fluidly coupled to the sealing gas feed circuit, and a sealing gas outlet fluidly coupled to the sealing gas feed circuit and adapted to booster the sealing gas pressure in the sealing gas feed circuit. The auxiliary compressor unit is further adapted to receive a gas flow from the main compressor, for instance a primary vent from the dry gas seal for recovery purposes.

Abstract: The system (100) is used for starting and synchronizing synchronous motors (10) with power electricity of an electric grid (20). The system (100) includes a variable frequency driver (30) for starting the synchronous motors (10), and an electrical diverter (61, 63) for each synchronous motor (10). The electrical diverter (61, 63) has a control input electrically coupled to a control output of the variable frequency driver (30) so to selectively couple stator windings (12) of synchronous motors (10) with a power output (33) of the variable frequency driver (30) or with the electric grid (20) based on signals that are received at a control input of the variable frequency driver (30) and represent a position of the shafts of the synchronous motors (10). Therefore, switching occurs at desired shafts positions.

Abstract: The disclosure concerns a waste heat recovery cycle system and related method in which a Brayton cycle system operates in combination with a Rankine cycle system. The Brayton cycle system has a heater configured to circulate a fluid, namely an inert gas, in heat exchange relationship with a heating source, such as an exhaust gas of a different system, in order to recover waste heat from such different system by heating the inert gas. The Rankine cycle system has a heat exchanger configured to circulate a second fluid, in heat exchange relationship with the inert gas of the Brayton cycle system to heat the second fluid while at the same time cooling the inert gas. The second fluid can be selected among fluids having a boiling point at a temperature lower than the temperature of the inert gas from the expansion unit/group in the Brayton cycle system.

Abstract: It is disclosed a method for reducing the pulsation level in a multi-compressor plant where each compressor of a plurality of compressors is driven by a respective motor. The method manages to reduce the pulsation level by starting a first motor of a first compressor and then starting in succession each one of the other motors in a way to synchronize all motors between each other with a specified phase shift.

Abstract: Positive drive valve actuating mechanisms useable to operate a valve of a reciprocating compressor for oil and gas industry and related methods are provided. The valve actuating mechanism includes a driver configured to perform a rotating motion and a follower connected to a mobile part of the valve and to the driver. The follower is configured to transform the rotating motion of the driver into a reciprocating motion to open the valve and to close the valve, respectively.

Abstract: A reciprocating compressor for the oil and gas industry, the reciprocating compressor has a chamber, a timing valve, an actuator and a controller. A fluid entering the chamber via a suction valve is compressed inside the chamber, and evacuated from the chamber via a discharge valve. The timing valve is located between the chamber and a fluid volume at a relief pressure that is lower than a pressure in the chamber when the timing valve is opened. The actuator is configured to actuate the timing valve. The controller is configured to control the actuator such that to open the timing valve during an expansion phase of the compression cycle, and to close the timing valve when the relief pressure becomes equal to the pressure in the chamber or when the suction valve is opened.

Abstract: It is disclosed a method for reducing the pulsation level in a multi-compressor plant where each compressor of a plurality of compressors is driven by a respective motor. The method manages to reduce the pulsation level by starting a first motor of a first compressor and then starting in succession each one of the other motors in a way to synchronize all motors between each other with a specified phase shift.

Abstract: Fluid flow adapter for a cylinder of a reciprocating compressor, the cylinder having a side wall provided with a valve seat, the fluid flow adapter comprising a filler element having an internal surface facing an internal volume of the cylinder and an external surface facing the valve, the filler element having at least a channel connecting the internal surface to the external surface, wherein the internal surface is flush with the side wall of the cylinder, the channel being configured to allow the passage of fluid between the internal volume of the cylinder and the valve.

Abstract: Apparatuses and methods overcoming the technical challenges in actuating valves of reciprocating compressors used in oil and gas industry are provided. A valve assembly includes an actuator, a shaft, a collar and a thrust bushing. The actuator is configured to generate a displacement. The shaft configured to receive a rotating motion caused by the displacement and to penetrate inside a compressor body of the reciprocating compressor. The collar is located close to a location where the shaft penetrates inside the compressor body. The thrust bushing is located between the collar and the compressor body. The rotating motion actuates a valve closing member of a valve inside the compressor body.

Abstract: A crosshead-piston rod assembly for a reciprocating compressor comprises a piston rod; a crosshead having a bore; a connection element attached to the piston rod and at least partially inserted into the bore for connecting the crosshead to a piston.

Abstract: A valve assembly in a reciprocating compressor used in oil and gas industry is provided. The valve assembly comprises an actuator configured to a valve actuating motion and a valve. The valve has a valve seat comprises an inlet port configured to allow a fluid to flow through the valve seat, a counter-seat comprising an outlet port configured to allow the fluid to flow through the counter-seat, and a valve closing member attached to the counter-seat and configured to cover the inlet port when the counter-seat is in a closed position. The counter-seat is configured to receive the valve actuating motion and to move between the closed position and an open position in which the valve closing member does not cover the inlet port thereby selectively allowing the fluid to flow on a flow path which comprises the inlet port and the outlet port.

Abstract: Cam actuated valves for compressors including mechanisms for changing an instant when the cam actuated valve is opened and/or a time interval during which the cam actuated valve is in an open state within the time range of a compression cycle. A reciprocating compressor has: a body including a compression chamber; a cam having an oblong portion, being located inside the body and being configured to be rotated around a rotation axis, to perform a rotation during each compression cycle; an actuating element located inside the body and configured to receive a linear displacement or an angular displacement due to the oblong portion of the cam; and a valve located on a flow path of the fluid toward or from the compression chamber and configured to be switched to an open state by the actuating element. The reciprocating compressor also includes a controller configured to adjust timing of the valve.

Abstract: A compressor includes a piston disposed in a housing and configured to be reciprocatably driven in the housing by an electromagnetic drive. A conventional linear motor drive assembly reciprocatably drives the piston in an embodiment. A magnetically-geared drive assembly reciprocatably drives the piston in another embodiment. A solenoid drive assembly reciprocatably drives the piston in another embodiment. A control system is coupled to the drive for varying piston displacement, and an accumulator conserves force by decelerating a translating assembly at the end of one stroke and accelerating the assembly in a subsequent stroke.

Abstract: A compressor including a pair of opposed pistons disposed in a housing and defining a compression chamber. An electromagnetic actuator reciprocatedly drives the pistons within the housing in cooperation with force accumulator. The force accumulators bank the force during a first reciprocation, decelerating the pistons, and apply the force in a subsequent reciprocation, thereby accelerating the pistons.

Abstract: Disclosed is a differential pressure valve comprising: a valve body, the valve body having at least one flow inlet and one flow outlet: at least one shutter, the shutter being movable between an open position and a closed position under a differential pressure across the valve; at least one flow passage from the flow inlet to the flow outlet; at least one biasing member configured to bias the shutter towards a closed position so as to block the flow passage through the flow inlet. The biasing member is a non-linear biasing member.

Abstract: Fluid flow adapter for a cylinder of a reciprocating compressor, the cylinder having a side wall provided with a valve seat, the fluid flow adapter comprising a filler element having an internal surface facing an internal volume of the cylinder and an external surface facing the valve, the filler element having at least a channel connecting the internal surface to the external surface, wherein the internal surface is flush with the side wall of the cylinder, the channel being configured to allow the passage of fluid between the internal volume of the cylinder and the valve.

Abstract: An actuated rotary valves for reciprocating compressors used in oil and gas industry, the valve including a stator with a stator opening, a rotor with a rotor opening, and an actuation mechanism. The actuation mechanism is configured to receive a rotation motion and to actuate the rotor to perform first an axial translation moving away from the stator and then a rotation. The actuation mechanism includes an outer shaft configured to receive the rotation motion, and an inner shaft inside the outer shaft and configured to rotate the rotor. The outer shaft is configured to rotate a predetermined angular displacement while pushing the rotor away from the stator before engaging the inner shaft to rotate together with the rotor.

Abstract: An automatic valve including a valve seat having first gas flow passages extending there through and a valve guard having second gas flow passages extending there through. The valve further comprises at least one shutter member movably arranged between the valve guard and the valve seat, at least one set of spring members biasing the at least one shutter member towards a closed position in sealing engagement with the valve seat to close the first gas flow passages, and at least one spring holder ring provided with a plurality of spring retention seats. Each spring member of the set of spring members is partially housed in a respective spring pocket formed in the valve guard and retained in a respective one of the spring retention seat.

Abstract: A crosshead-piston rod assembly for a reciprocating compressor comprises a piston rod; a crosshead having a bore; a connection element attached to the piston rod and at least partially inserted into the bore for connecting the crosshead to a piston.

Abstract: A crosshead for a piston rod comprises a main body having a first seat and a second seat being configured to hold a connecting rod, the second seat being configured to hold a piston rod; the main body comprising a linking portion defining at least partially the first seat and the second seat for holding respectively the connecting rod and the piston rod; the main body comprising a closing portion defining at least partially the second seat and being configured to secure the piston rod inside the second seat.