A pump body of a high-pressure pump includes a pressure chamber formed in a deep portion of a cylinder. The pump body closes the pressure chamber on a side opposite to a plunger. The plunger reciprocates within the cylinder to vary a volume of the pressure chamber. The large-diameter portion provided at an end of the plunger on a side protruding to the pressure chamber has an outside diameter larger than an inside diameter of the cylinder and smaller than an inside diameter of the pressure chamber. In this case, the large-diameter portion is engaged with a step portion between the cylinder and the pressure chamber in a state before attachment of the high-pressure pump to an internal combustion engine. Accordingly, separation of the plunger from the cylinder is avoidable.

Embodiments of the invention provide a pump assembly for a hydraulic tool. The pump assembly can include a reciprocating element that is configured to move between a retracted position and an extended position, a cam surface in the reciprocating element that can engage cam followers, a rotating element that can receive rotational input, and a base that can at least partially surrounds the rotating element. Movement of the cam followers along the cam surface can move the reciprocating element from the retracted position to the extended position.

Embodiments of the invention provide a pump assembly for a hydraulic tool. The pump assembly can include a reciprocating element that is configured to move between a retracted position and an extended position, a cam surface in the reciprocating element that can engage cam followers, a rotating element that can receive rotational input, and a base that can at least partially surrounds the rotating element. Movement of the cam followers along the cam surface can move the reciprocating element from the retracted position to the extended position.

The present disclosure provides a high-pressure fuel pump having barrel sets comprising offset, opposing barrel units within the same plane and having plungers disposed therein. The high-pressure fuel pump further includes a camshaft having at least one offset lobe and a cam ring encircling the lobe and in contact with the plungers, which translate the rotational movement of the camshaft to longitudinal movement of the plungers, controlling inflow, compression, and outflow of fuel within the pump.

The present disclosure provides a high-pressure fuel pump having barrel sets comprising offset, opposing barrel units within the same plane and having plungers disposed therein. The high-pressure fuel pump further includes a camshaft having at least one offset lobe and a cam ring encircling the lobe and in contact with the plungers, which translate the rotational movement of the camshaft to longitudinal movement of the plungers, controlling inflow, compression, and outflow of fuel within the pump.

A cam ring of a supply pump revolves around a camshaft without rotating. A tappet reciprocates in a direction perpendicular to the camshaft in response to revolution of the cam ring such that the tappet slides along a cam ring sliding surface. A plunger reciprocates together with the tappet to pressurize and deliver fuel. The cam ring sliding surface is shaped in a convex form that has a curved contour line which is non-circular. A height of an inside of the cam ring sliding surface is higher than a height of a periphery of the cam ring sliding surface. Specifically, an ellipsoidal surface portion is formed at the cam ring sliding surface, and an axial direction of a major axis of the ellipsoidal surface portion is set to coincide with a direction perpendicular to a sliding direction of the cam ring sliding surface.

In a reciprocating high-pressure fuel pump that operates a plunger while facing a cam ridge of a plunger driving cam provided on a camshaft to which power of a crankshaft of an internal combustion engine is transmitted, the cam ridge includes a cam curved surface including two apexes at a cam angle interval of 180° and two valley bottoms at a cam angle interval of 180° and alternately connecting the apexes and the valley bottoms, and a crossing angle between a first virtual line connecting the two apexes and a second virtual line connecting the two valley bottoms is not a right angle as viewed in a direction of a camshaft axis.

Systems and methods to enhance the flow of fracturing fluid into a wellhead during a high-pressure fracturing operation may include providing a pump frame and a crankshaft. A plurality of first plungers may be connected to the crankshaft and may reciprocate in a first plane. The hydraulic fracturing pump also may include a plurality of second plungers connected to the crankshaft and positioned to reciprocate in a second plane. The first plane and the second plane may define a non-zero offset angle between the first plane and the second plane. The crankshaft may include a plurality of crankpins, and each of the crankpins may be connected to one of the first plungers and one of the second plungers. The first plungers may pump a first fracturing fluid and the second plungers may pump a second fracturing fluid different from the first fracturing fluid.

A rotational output assembly is configured to provide power to a drive assembly to cause pumping by a pump. The rotational output assembly includes an electric motor and a pinion drive projecting axially from the motor. The pinion drive interfaces with bearings supported on a pump frame. The pinion drive includes a gear teeth section between portions interfacing with the bearings supported on the pump frame. The gear teeth section interfaces with a drive gear of the drive assembly to cause rotation of the drive gear.

The invention relates to a radial reciprocating engine (1) having cylinders (5) arranged in a cylinder carrier (16) and a piston element (21) arranged in each cylinder (5) that is connected to a guide element (22), wherein the guide element (22) runs on a slide surface (14), whereby a stroke movement is imposed on the piston element (21). Since the piston element (21) is spherical at least in the region of the piston element (21) which seals the inner walls (51) of the cylinder (5) during the stroke movements, a linear seal is created, which enables a more compact design in comparison to radial pumps with cylindrical piston elements.