A pump may generally include a frame including a reservoir. The reservoir stores a hydraulic fluid. The pump may also include a motor assembly supported by the frame and a pump assembly operably driven by the motor assembly. The pump assembly is in fluid communication with the reservoir and configured to dispense the hydraulic fluid out of the frame. The pump assembly includes a first piston and a second piston, wherein the first piston dispenses hydraulic fluid out of the frame between a first pressure and a second pressure greater than the first pressure, and the second piston dispenses hydraulic fluid out of the frame between the first pressure and a third pressure, the third pressure being greater than the second pressure.

A pump may generally include a frame including a reservoir. The reservoir stores a hydraulic fluid. The pump may also include a motor assembly supported by the frame and a pump assembly operably driven by the motor assembly. The pump assembly is in fluid communication with the reservoir and configured to dispense the hydraulic fluid out of the frame. The pump assembly includes a first piston and a second piston, wherein the first piston dispenses hydraulic fluid out of the frame between a first pressure and a second pressure greater than the first pressure, and the second piston dispenses hydraulic fluid out of the frame between the first pressure and a third pressure, the third pressure being greater than the second pressure.

The present invention provides a high-pressure pump. The high-pressure pump comprises a motor assembly, a gear assembly, a plunger assembly, a pump head assembly and a water inlet and outlet valve assembly. The motor assembly comprises a motor and a dual-layer housing. An annular water channel surrounding a motor stator is formed at the dual-layer housing. The periphery of the motor stator coil is filled with heat-conductive material, and the heat of the motor stator coil is conducted to the annular water channel through the heat-conductive material to perform active heat dissipation for the motor stator coil. Therefore, the cooling efficiency is high and the structure is simple.

The present disclosure is directed to a system for fracturing operation in oil/gas fields. The disclosed fracturing system is integrated onto a semitrailer that can be conveniently transported to any oil field. The disclosed fracturing system further includes major components needed for delivering high-pressure fracturing fluid into a wellhead, including but not limited to at least one power generation source and at least one plunger pump driven by the at least one power generation source via simple transmission mechanisms utilizing reduction gearbox and/or transmission shafts. The power generation source, in particular, includes a turbine engine capable of being powered by 100% natural gasified liquid fuel. The fracturing system further includes hydraulic and cooling component for serving the various needs for the turbine engine, the reduction gearbox, and the plunger pump, such as lubrication of various moving parts

Systems and methods to enhance the flow of fracturing fluid into a wellhead during a high and the second plungers may pump a second fracturing fluid different from the first fracturing fluid.

Systems and methods to enhance the flow of fracturing fluid into a wellhead during a high and the second plungers may pump a second fracturing fluid different from the first fracturing fluid.

A hydraulic fracturing pump includes a power end with a plurality of torsion tubes extending between sides of a crankcase housing in which a crankshaft is rotatably mounted. The crankshaft is coupled by piston arms to crossheads disposed to reciprocate along crosshead axes that are perpendicular to the crankshaft. Disposed within the crankcase housing are a plurality of ribs generally perpendicular to the crankshaft and extending from the base of the crankshaft housing to an upper surface of the crankshaft housing. The torsion tubes are generally adjacent the upper surface of the crankcase housing and pass perpendicularly through each of the plurality of ribs and are attached to the ribs to provide rigidity to the power end.

A method for determining a current wear (w) of a hydrostatic pump, particularly of a radial piston pump, with a variable-speed drive, where the pump is connected to a fluid passage, in which a fluid is pumped by the pump to create a current actual volume flow in the fluid passage. A current actual volume flow (Q.sub.act) is determined, by measuring the volume flow in the fluid passage at a predetermined drive-vector, a computed volume flow (Q.sub.comp) is determined, by a first computational method, at the predetermined drive-vector, and the current wear (w) of the pump is determined, by a second computational method, which relates the current actual volume flow (Q.sub.act) to the computed volume flow (Q.sub.comp).

A piston pump and a piston motor are provided. The piston pump includes a cylinder body, a piston, a main shaft, an end cover, and an oil dispensing mechanism. The oil dispensing mechanism includes an oil suction mechanism and an oil discharging mechanism. A roller is mounted on the piston, and the roller is rotatablely connected to the piston. A driving wheel is arranged on the main shaft, and the driving wheel is mounted in cooperation with the main shaft or is integrally formed with the main shaft. A driving groove is formed on the driving wheel, and a roller-path surface of the driving groove is a curved surface. The size of the driving groove is adapted to the size of an outer circle of the roller. The main shaft rotates to drive the driving wheel to rotate to further drive the piston to move along the cylinder bore.

An apparatus comprising a synthetically commutated machine with one or more services, a prime mover coupled to the machine, a hydraulic circuit extending between the services and hydraulic loads to fluidically connect the services to the hydraulic loads such that groups of one or more services are fluidically connected to respective groups of one or more hydraulic loads. The apparatus configured such that the flow of hydraulic fluid to or from a group of services of the machine is controlled responsive to measuring a flow rate and/or pressure requirement of the hydraulic loads which are fluidically connected to the services, or receiving a demand signal indicative of a demanded pressure and/or flow rate based on a pressure and/or flow demand of hydraulic loads which are fluidically connected to the services.