A pump includes a pair of valves, coupled to a camshaft that selectively opens and closes the valves such that when one valve opens the other valve closes. The valves are in fluid communication with a piston chamber. A crankshaft operates a piston in a piston cylinder with the opening and closing of the valves such that as the piston is drawn from the piston chamber, the inlet valve is open and the outlet valve is closed and when the piston is forced into the chamber, the outlet valve is open and the inlet valve is closed. The camshaft and crankshaft are coupled together to cause synchronous operation of the valves and piston.

A plate segment for a reciprocating pump power end frame assembly, the power end frame assembly having a pair of end plate segments and at least one middle plate segment disposed between the end plate segments. The plate segment consists of the middle plate segment or one of the pair of end plate segments and includes a plate having a front wall, a rear wall, a top wall, a bottom wall and a pair of sidewalls and at least one opening forming a bearing support surface, the opening extending through the plate. The plate segment further includes at least one extension extending from at least one of the sidewalls of the plate at a position to align with and contact a corresponding extension on an adjacently positioned plate.

A plate segment for a reciprocating pump power end frame assembly, the power end frame assembly having a pair of end plate segments and at least one middle plate segment disposed between the end plate segments. The plate segment consists of the middle plate segment or one of the pair of end plate segments and includes a plate having a front wall, a rear wall, a top wall, a bottom wall and a pair of sidewalls and at least one opening forming a bearing support surface, the opening extending through the plate. The plate segment further includes at least one extension extending from at least one of the sidewalls of the plate at a position to align with and contact a corresponding extension on an adjacently positioned plate.

A power end frame assembly for a reciprocating pump that includes a first and second end plate segment each including annular bearing support surfaces configured to support a crankshaft bearing assembly. At least one middle plate segment is disposed between the first and second end plate segments and includes an annular bearing support surface configured to support a crankshaft bearing assembly. The annular bearing support surfaces of the first and second end plate segments and the at least one middle plate segment each have a diameter and are coaxially aligned. The diameter of at least one of the first and second end plate segments is different from the diameter of the at least one middle plate segment to facilitate insertion and removal of the crankshaft bearing assembly from the power end frame assembly.

Method and apparatus overcoming gas-lock in reciprocating downhole pumps. On the downstroke of a plunger in a barrel, gassy fluid is compressed in the pump chamber between standing and travelling valves. Downhole plunger movement drags a sleeve over a mandrel for opening a chamber valve to a staging chamber located at a downhole end of the travelling valve for receiving at least a portion of the compressed and gassy fluid therein. On the upstroke, the chamber valve is dragged closed for sealably retaining the compressed gassy fluid therein while drawing an additional increment of fluid through the standing valve into the pump chamber. Continued downstroke and upstroke cycles increases pressure of the compressed gassy fluid in the pump chamber until it exceeds the hydrostatic head above the travelling valve for resumption of normal fluid pumping.

A power end frame assembly for a reciprocating pump that includes a first and second end plate segment each including annular bearing support surfaces configured to support a crankshaft bearing assembly. At least one middle plate segment is disposed between the first and second end plate segments and includes an annular bearing support surface configured to support a crankshaft bearing assembly. The annular bearing support surfaces of the first and second end plate segments and the at least one middle plate segment each have a diameter and are coaxially aligned. The diameter of at least one of the first and second end plate segments is different from the diameter of the at least one middle plate segment to facilitate insertion and removal of the crankshaft bearing assembly from the power end frame assembly.

A control device for controlling a displacement pump or motor, comprising a variable mechanical device, comprising at least two masks, wherein the at least two masks are phased relative to each other and a shaft, and are configured to create a desired cam profile. A cam follower is operatively connected to at least one of an intake valve an output valve of a displacement pump or motor.

A skid for supporting a reciprocating pump assembly, the reciprocating pump assembly including a power end frame assembly having a pair of end plate segments and a plurality of middle plate segments disposed between the end plate segments. The end plate segments each have at least a pair of feet and the middle plate segments each having at least one foot. The skid includes a base and a plurality of pads extending from the base. At least a portion of the plurality of pads correspond to the end plate segment feet and at least another portion of the plurality of pads correspond to the at least one foot of each middle plate segment.

It is provided a dosage pump (10) comprising a pump housing (12), a first valve (18), a second valve (20), an actuation lever (22), wherein the actuating lever (22) is adapted to be tilted around a tilting axis (24), a disc (34) for providing a torque, wherein the disc (34) is adapted to rotate around an input axis, a first cam (26) connected to the disc (34) and a second cam (30) connected to the disc (34), wherein the actuating lever (22) comprises a first raceway (28), wherein the first raceway (28) and the second raceway (32) are formed such that at least partially during an angle of rotation of the disc (34), where the actuation lever (22) has to apply an actuation force for opening and/or closing the first valve (18) and/or the second valve (20), the first cam (26) or the second cam (30), whose contact point to its corresponding raceway (28, 32) is farer away from the tilting axis (24) of the actuation lever (22) and/or adjusted to a lower torque at the actual angle of rotation of the disc (34), provides the tilting force onto the actuation lever (22). Due to the at least two cams (26, 30) the actuation force at the valves (18, 20) can be provided by means of the cam (26, 30) with a large lever arm, so that a lower torque of the disc (34) is sufficient, which can be generated with a lower energy consumption.

A skid for supporting a reciprocating pump assembly, the reciprocating pump assembly including a power end frame assembly having a pair of end plates and a plurality of middle plates disposed between the end plates. The end plates each have at least a pair of feet and the middle plates each having at least one foot. The skid includes a base and a plurality of pads extending from the base. At least a portion of the plurality of pads correspond to the end plate feet and at least another portion of the plurality of pads correspond to the at least one foot of each middle plate.