A reciprocating pump (10) comprises a first upright leg (12), a second upright leg (14), a first cross-over conduit (18), a second cross-over conduit (18), a lower valve assembly (20) and an upper drive assembly (22). The drive assembly includes plungers (30) which exert alternating downward pumping forces on columns of liquid in the legs (12, 14). The valve assembly is located in a reservoir of water (55) and includes suction openings (80, 64) in the water, which lead into the cross-over conduits (18) and (18), respectively. The valve assembly includes a system of valves and pistons (74, 76) for controlling flow of water into the legs (12, 14) via the cross-over conduits (12, 14) when pumping forces are alternately applied to columns of wafer in the legs (12, 14) wherein water in the legs is raised and lowered in alternating pendulum fashion. Water is drawn into and alternately forced along the cross-over conduits into the legs where the water is pumped from upper ends of the legs (12, 14) via slots (31) defined in the plungers.

A reciprocating pump (10) comprises a first upright leg (12), a second upright leg (14), a first cross-over conduit (18), a second cross-over conduit (18), a lower valve assembly (20) and an upper drive assembly (22). The drive assembly includes plungers (30) which exert alternating downward pumping forces on columns of liquid in the legs (12, 14). The valve assembly is located in a reservoir of water (55) and includes suction openings (80, 64) in the water, which lead into the cross-over conduits (18) and (18), respectively. The valve assembly includes a system of valves and pistons (74, 76) for controlling flow of water into the legs (12, 14) via the cross-over conduits (12, 14) when pumping forces are alternately applied to columns of wafer in the legs (12, 14) wherein water in the legs is raised and lowered in alternating pendulum fashion. Water is drawn into and alternately forced along the cross-over conduits into the legs where the water is pumped from upper ends of the legs (12, 14) via slots (31) defined in the plungers.

A hydraulic system is provided for powering one or more external hydraulically powered devices. The system includes one or more pumping systems attached to a common crankshaft and including an inner sleeve, an outer sleeve, a valve member and an end body. The system can include a pair of high pressure fluid tanks and a low pressure fluid tank. The pumping systems can increase the fluid pressure within the high pressure fluid tanks back and forth and in a sequenced manner, and force the higher pressure fluid through the one or more powered devices. Drive systems are provided to assist the pumping systems in rotating the common crankshaft. The drive systems can include a piston assembly for rotating the crankshaft and a valving system for directing fluid into the piston assembly to power the piston assembly.

An example apparatus includes a housing including an inlet and an outlet. The example apparatus also includes a rotor defining a bore. The rotor is disposed in the housing. The example apparatus further includes a piston disposed in the bore. A motor is operatively coupled to the rotor to rotate the rotor from a first position to a second position. The bore is to be in fluid communication with the inlet and the outlet when the rotor is in the second position.

An example apparatus includes a housing including an inlet and an outlet. The example apparatus also includes a rotor defining a bore. The rotor is disposed in the housing. The example apparatus further includes a piston disposed in the bore. A motor is operatively coupled to the rotor to rotate the rotor from a first position to a second position. The bore is to be in fluid communication with the inlet and the outlet when the rotor is in the second position.

A reciprocating pump (10) comprises a first upright leg (12), a second upright leg (14), a first cross-over conduit (18), a second cross-over conduit (18), a lower valve assembly (20) and an upper drive assembly (22). The drive assembly includes plungers (30) which exert alternating downward pumping forces on columns of liquid in the legs (12, 14). The valve assembly is located in a reservoir of water (55) and includes suction openings (80, 64) in the water, which lead into the cross-over conduits (18) and (18), respectively. The valve assembly includes a system of valves and pistons (74, 76) for controlling flow of water into the legs (12, 14) via the cross-over conduits (12, 14) when pumping forces are alternately applied to columns of wafer in the legs (12, 14) wherein water in the legs is raised and lowered in alternating pendulum fashion. Water is drawn into and alternately forced along the cross-over conduits into the legs where the water is pumped from upper ends of the legs (12, 14) via slots (31) defined in the plungers.

An apparatus for pumping a fluid from a fluid inlet to a fluid outlet is disclosed. The apparatus comprises: a spool axially movable within a cavity, wherein a first chamber is located at a first axial end of the cavity and a second chamber is located at a second axial end of the cavity, wherein the volume of the first chamber and the second chamber varies depending upon the axial position of the spool within the cavity; a valve movable between a first position and a second position, wherein in the first position the valve is configured to convey fluid from the fluid inlet to the first chamber and from the second chamber to the fluid outlet, and in the second position the valve is configured to convey fluid from the fluid inlet to the second chamber and from the first chamber to the fluid outlet.

A piston includes a piston housing and a decompression valve disposed in the piston housing. The decompression valve includes a valve housing seated in the piston housing and a valve member moveably received by the valve housing. The valve member has a radially outer surface including an annular shoulder. In addition, the piston includes an end cap secured to the first end of the piston housing. A radially inner surface of the end cap includes an annular valve seat. The decompression valve has a closed position with the annular shoulder of the valve member engaging the valve seat of the end cap and an open position with the annular shoulder of the valve member axially spaced from the valve seat of the end cap. The piston also includes a biasing member configured to bias the decompression valve to the closed position.

A piston includes a piston housing and a decompression valve disposed in the piston housing. The decompression valve includes a valve housing seated in the piston housing and a valve member moveably received by the valve housing. The valve member has a radially outer surface including an annular shoulder. In addition, the piston includes an end cap secured to the first end of the piston housing. A radially inner surface of the end cap includes an annular valve seat. The decompression valve has a closed position with the annular shoulder of the valve member engaging the valve seat of the end cap and an open position with the annular shoulder of the valve member axially spaced from the valve seat of the end cap. The piston also includes a biasing member configured to bias the decompression valve to the closed position.

A hydraulic intensifier comprising a reciprocating differential piston arrangement and a controller configured to control the supply of low pressure hydraulic fluid to the intensifier is provided. The controller comprises at least one solenoid operated pilot valve and electronic operator configured to operate the pilot valve.