Abstract: A dry gas mechanical seal system configured to inhibit the emission of process gas. The mechanical seal system having tandem first and second stage seals, and a single separation gas supply subsystem configured to direct a supply of separation gas from an inlet through interfacing portions of the first stage seal into a process cavity and from the inlet through the interfacing portions of the second stage seal and out through an outlet to the atmosphere, thereby inhibiting the emission of process gas between a compressor housing and a rotating compressor shaft.

Abstract: A dry gas mechanical seal system configured to inhibit the emission of process gas. The mechanical seal system having tandem first and second stage seals, and a single separation gas supply subsystem configured to direct a supply of separation gas from an inlet through interfacing portions of the first stage seal into a process cavity and from the inlet through the interfacing portions of the second stage seal and out through an outlet to the atmosphere, thereby inhibiting the emission of process gas between a compressor housing and a rotating compressor shaft.

Abstract: A dry gas mechanical seal system configured to inhibit the emission of process gas. The mechanical seal system having tandem first and second stage seals, and a single separation gas supply subsystem configured to direct a supply of separation gas from an inlet through interfacing portions of the first stage seal into a process cavity and from the inlet through the interfacing portions of the second stage seal and out through an outlet to the atmosphere, thereby inhibiting the emission of process gas between a compressor housing and a rotating compressor shaft.

Abstract: A mechanical seal assembly with an electronically controllable carrier load. The assembly includes a magnetic ring affixed to the carrier and driven by a solenoid. The solenoid can apply an axial force to the carrier. The carrier load can be controlled to prevent or reduce friction between the primary ring and mating ring in slow-roll running conditions by partially or completely compensating a spring force provided by a biasing mechanism. The carrier load can further be controlled to inhibit seal hang-up. In embodiments, desired the carrier load can be determined by rotational speed. In embodiments, carrier load can be determined based on sensor signals.

Abstract: A dry gas mechanical seal system configured to inhibit the emission of process gas. The mechanical seal system having tandem first and second stage seals, and a single separation gas supply subsystem configured to direct a supply of separation gas from an inlet through interfacing portions of the first stage seal into a process cavity and from the inlet through the interfacing portions of the second stage seal and out through an outlet to the atmosphere, thereby inhibiting the emission of process gas between a compressor housing and a rotating compressor shaft.

Abstract: A dry gas mechanical seal system configured to inhibit the emission of process gas. The mechanical seal system having tandem first and second stage seals, and a single separation gas supply subsystem configured to direct a supply of separation gas from an inlet through interfacing portions of the first stage seal into a process cavity and from the inlet through the interfacing portions of the second stage seal and out through an outlet to the atmosphere, thereby inhibiting the emission of process gas between a compressor housing and a rotating compressor shaft.

Abstract: A mechanical seal assembly with an electronically controllable carrier load. The assembly includes a magnetic ring affixed to the carrier and driven by a solenoid. The solenoid can apply an axial force to the carrier. The carrier load can be controlled to prevent or reduce friction between the primary ring and mating ring in slow-roll running conditions by partially or completely compensating a spring force provided by a biasing mechanism. The carrier load can further be controlled to inhibit seal hang-up. In embodiments, desired the carrier load can be determined by rotational speed. In embodiments, carrier load can be determined based on sensor signals.

Abstract: A mechanical seal assembly with an electronically controllable carrier load. The assembly includes a magnetic ring affixed to the carrier and driven by a solenoid. The solenoid can apply an axial force to the carrier. The carrier load can be controlled to prevent or reduce friction between the primary ring and mating ring in slow-roll running conditions by partially or completely compensating a spring force provided by a biasing mechanism. The carrier load can further be controlled to inhibit seal hang-up. In embodiments, desired the carrier load can be determined by rotational speed. In embodiments, carrier load can be determined based on sensor signals.

Abstract: A mechanical seal system configured to inhibit the emission of process gas from a rotating machine. An annular plunger is axially slidable between a inboard closed position and an outboard open position such that when the plunger is in the closed position, the plunger inhibits the flow of the sealing fluid between the inlet passageway to the seal interface, and when the plunger is in the closed position, the plunger enables the flow of the sealing fluid between the inlet passageway and the seal interface. A biasing mechanism and solenoid provide opening and closing forces to the plunger. Normally-open and normally-closed configurations are provided.

Abstract: A dry gas mechanical seal system configured to inhibit the emission of process gas. The mechanical seal system having tandem first and second stage seals, and a single separation gas supply subsystem configured to direct a supply of separation gas from an inlet through interfacing portions of the first stage seal into a process cavity and from the inlet through the interfacing portions of the second stage seal and out through an outlet to the atmosphere, thereby inhibiting the emission of process gas between a compressor housing and a rotating compressor shaft.

Abstract: A dry gas mechanical seal system configured to inhibit the emission of process gas. The mechanical seal system having tandem first and second stage seals, and a single separation gas supply subsystem configured to direct a supply of separation gas from an inlet through interfacing portions of the first stage seal into a process cavity and from the inlet through the interfacing portions of the second stage seal and out through an outlet to the atmosphere, thereby inhibiting the emission of process gas between a compressor housing and a rotating compressor shaft.

Abstract: A mechanical seal assembly with an electronically controllable carrier load. The assembly includes a magnetic ring affixed to the carrier and driven by a solenoid. The solenoid can apply an axial force to the carrier. The carrier load can be controlled to prevent or reduce friction between the primary ring and mating ring in slow-roll running conditions by partially or completely compensating a spring force provided by a biasing mechanism. The carrier load can further be controlled to inhibit seal hang-up. In embodiments, desired the carrier load can be determined by rotational speed. In embodiments, carrier load can be determined based on sensor signals.

Abstract: An actuator assembly of a digital inlet valve for a fuel pump adapted to cooperate with an inlet valve member includes an actuator body in which is fixed a coil, a cover closing the body and, a magnetic core arranged in a core guiding bore provided in the actuator body. The magnetic core is slidable along a main axis in order, in use, to close an air gap under the influences of a first compression spring, and of a magnetic field, the core cooperating with the valve member.

Abstract: An inlet valve assembly for a high-pressure fuel pump is disclosed. The inlet valve assembly comprises an inlet valve member moveable between open and closed positions to control the fuel flow from a source of low-pressure fuel to a pumping chamber of the fuel pump, a first biasing spring arranged to apply a first force to the valve member in an opening direction, a second biasing spring arranged to apply a second force to the valve member in a closing direction, and an actuator arrangement operable to remove the first force from the valve member, thereby to allow the valve member to move into its closed position.

Abstract: A mechanical seal system configured to inhibit the emission of process gas from a rotating machine. An annular plunger is axially slidable between a inboard closed position and an outboard open position such that when the plunger is in the closed position, the plunger inhibits the flow of the sealing fluid between the inlet passageway to the seal interface, and when the plunger is in the closed position, the plunger enables the flow of the sealing fluid between the inlet passageway and the seal interface. A biasing mechanism and solenoid provide opening and closing forces to the plunger. Normally-open and normally-closed configurations are provided.

Abstract: A dry gas mechanical seal system configured to inhibit the emission of process gas. The mechanical seal system having tandem first and second stage seals, and a single separation gas supply subsystem configured to direct a supply of separation gas from an inlet through interfacing portions of the first stage seal into a process cavity and from the inlet through the interfacing portions of the second stage seal and out through an outlet to the atmosphere, thereby inhibiting the emission of process gas between a compressor housing and a rotating compressor shaft.

Abstract: A pressure limiting valve communicates between a closed state, where a ball is biased against a valve seat along a contacting line and, an open state, where the ball is at a distance of the valve seat enabling fluid under pressure to exit via a relief orifice opening in the valve seat. The valve seat is shaped so that in the closed state of the valve, the contacting line between the ball and the valve seat is at a distance from the relief orifice opening.

Abstract: A valve arrangement comprising: a valve outlet for communication with a low pressure drain; a valve housing provided with a bore for receiving fuel from an accumulator volume; and a valve member having a closed position in which it engages a valve seating defined by the bore to prevent fuel flow from the accumulator volume to the valve outlet. The valve arrangement further comprises a first restricted flow means for restricting the flow of fuel between the accumulator volume and the valve outlet during a first stage of valve opening movement; a second restricted flow means effective during a second stage of valve opening movement to provide a greater restriction than during the first stage; and a third restricted flow means effective during a third stage of valve opening movement to provide a variable restriction to fuel flow dependent on the extent of opening movement of the valve member.

Abstract: A valve arrangement comprising: a valve outlet for communication with a low pressure drain; a valve housing provided with a bore for receiving fuel from an accumulator volume; and a valve member having a closed position in which it engages a valve seating defined by the bore to prevent fuel flow from the accumulator volume to the valve outlet. The valve arrangement further comprises a first restricted flow means for restricting the flow of fuel between the accumulator volume and the valve outlet during a first stage of valve opening movement; a second restricted flow means effective during a second stage of valve opening movement to provide a greater restriction than during the first stage; and a third restricted flow means effective during a third stage of valve opening movement to provide a variable restriction to fuel flow dependent on the extent of opening movement of the valve member.

Abstract: An inlet valve assembly for a high-pressure fuel pump is disclosed. The inlet valve assembly comprises an inlet valve member moveable between open and closed positions to control the fuel flow from a source of low-pressure fuel to a pumping chamber of the fuel pump, a first biasing spring arranged to apply a first force to the valve member in an opening direction, a second biasing spring arranged to apply a second force to the valve member in a closing direction, and an actuator arrangement operable to remove the first force from the valve member, thereby to allow the valve member to move into its closed position.