A piston includes a piston cap and a piston rod with the piston cap being removable from the piston rod body. The piston cap includes a cap body and a socket extending into the cap body. A mounting portion of the piston rod body extends into the socket of the cap body to connect the piston rod body to the piston cap. A wear sleeve is mounted on the piston rod.

A compressor of an embodiment includes: a piston that is housed in a case and moves back and forth in an axis direction inside the case; a main shaft that i) extends in the axis direction inside the case, and ii) guides the piston to move in the axis direction; and a drive that drives the piston to move along the axis direction. The piston includes: a main shaft bush through which the main shaft passes in the axis direction; and a compression board that has an outer diameter greater than an outer diameter of the main shaft bush, and that is fixed to an end portion of the main shaft bush on a side in the axis direction. Fluid inside the case is compressed, and then is ejected to an outside of the case. The drive is arranged between the compression board and an end portion of the case.

A drive system for a fluid displacement pump includes an electric motor, a drive coupled to the rotor at a first end of the electric motor, a pump including a fluid displacement member mechanically coupled to the drive, and a controller configured to control a level of power to the electric motor based on a pressure setting set by a user. The electric motor includes a stator and a rotor disposed on an axis. The drive coupled to the rotor converts the rotational output to a linear, reciprocating input to power a pump.

A compressor unit includes: a reciprocating compressor main body having a drive portion and a compression portion driven by the drive portion to compress a hydrogen gas; an electric motor that is a power source of the drive portion; a hydrogen supply flow path which is connected to a suction side flow path and to the compressor main body and through which a hydrogen gas flows; a fuel cell module that is disposed in the hydrogen station, generates electric power using a hydrogen gas guided through the hydrogen supply flow path, and supplies the generated electric power to the electric motor; and an inverter that adjusts a rotation speed of the electric motor.

A system for dispensing abrasive materials includes a transfer pump configured to pump abrasive material to a metering pump configured to pump the abrasive material to an application. Dynamic interfaces within the pumps are at least partially formed by sleeved components of the pump interfacing with a seal configured to engage with the sleeved surface during relative movement between the sleeved surface and the seal. The smooth exterior surfaces of the sleeves interface with the seals to prevent abrasive particulate in the material from adhering to the sleeve, preventing the abrasive particulate from being pulled between the sleeve and the seal.

A drive system for a fluid displacement pump includes an electric motor, a drive coupled to the rotor at a first end of the electric motor, a fluid displacement member mechanically coupled to the drive, and a pump frame mechanically coupled to the electric motor. The electric motor includes a stator and a rotor disposed on an axis. The drive coupled to the rotor converts the rotational output to a linear, reciprocating input to the fluid displacement member. The rotor is disposed about the stator to rotate about the stator.

Apparatus and methods for measuring backlash of a gear train of a pump unit for pumping a fluid. An example method may include locking a crankshaft of the pump unit such that the crankshaft cannot rotate. The method may further include commencing operation of a processing device to receive rotational position measurements indicative of rotational position of an output shaft of a prime mover, cause the prime mover to rotate the output shaft in a first direction until the output shaft reaches a first rotational position, and cause the prime mover to rotate the output shaft in a second direction until the output shaft reaches a second rotational position. The processing device may then determine backlash of the gear train by determining rotational distance between the first rotational position of the output shaft and the second rotational position of the output shaft.

An oscillating positive displacement pump with at least one mobile part arranged to be movable relative to a fixed part. The mobile part is driven and drives a displacement element of the positive displacement pump. An electrodynamic drive is provided as a drive, on which a plurality of coils and permanent magnets are provided that are arranged on the mobile part of the drive respectively, and at least one guide member is provided on the drive, which allows the mobile part to move only along a degree of translation freedom. The positive displacement pump is designed as a diaphragm pump, which is associated with a measurement and control unit with a data storage and data processor, which processes a position signal of the mobile part and the strength of the drive current as a measured and/or control variable. An arrangement of a plurality of such positive displacement pumps and a method of operating at least one such oscillating positive displacement pump are also provided.

The present invention discloses a high-power five cylinder plunger pump. The high-power five cylinder plunger pump has a stroke of 10 inches, a cylinder spacing of 11.5 inches, and a braking power of 5000 HP. Beneficial effects: high power, large displacement; suitable for electric drive fracturing and turbine fracturing; an integral power end assembly or a split-type power end assembly could be selected according to specific operation conditions, thus better implementing the arrangement of fracturing units or fracturing vehicles; the dimension of the cylinder spacing ensures stable operations under a 5000 HP braking power with a long stroke.

A piston includes a piston cap, a piston rod body, and a piston head, with the piston cap being removable from the piston rod body. The piston cap includes a cap body and a connecting portion extending from the cap body and away from the piston rod body. The connecting portion includes a neck and a cap head with the cap head connected to an end of the neck disposed opposite the piston rod body. The cap head is wider than the neck. A mounting portion of the piston rod body extends into a receiving portion of the cap body to connect the piston rod body to the piston cap.