A piston pump is disclosed suitable to be installed on machines for dispensing fluid products, comprising a jacket, a piston device mobile with alternate motion inside said jacket and comprising a rod and a head. The pump also comprises a pipe for fluids to enter and a pipe for fluids to exit, said pipes being disposed on the same side of the jacket and on opposite sides with respect to the piston device.

[Problems] To provide a driving method for a metering pump, a driving apparatus for a metering pump, a vaporizer and an anesthesia apparatus which are capable of suppressing a pulsation in the metering pump, and lowering the costs and reducing the sizes of the vaporizer and the anesthesia apparatus.

[Means for solving the Problems] A metering pump 16 is joined to the stepping motor 15, includes an eccentric mechanism converting a revolving motion of the stepping motor 15 into a reciprocating motion of a plunger 16A, and makes a constant liquid delivery by sucking and discharging an anesthetic agent through variations in the cubic volume of a cylinder 16D caused by the reciprocating motion of the plunger 16A. The control section 12: calculates a suction and discharge cycle T of the metering pump 16 on the basis of a set anesthetic-gas concentration and a fresh-gas flow rate; sets a discharge period T2 of the cycle T to be longer than a suction period T1 of the cycle T; and controls the revolution speed of the stepping motor 15 so that the travelling speed of the plunger 16A is kept constant during the discharge period T2.

An example hydraulic pump comprises: a housing; an input shaft extending from the housing; a seal disposed within the housing and positioned about the input shaft; and a seal guard member positioned about the input shaft and mounted to the housing at an interface between the input shaft and the housing, wherein the seal guard member is configured to allow rotation of the input shaft without rotating therewith.

An example hydraulic pump comprises: a housing; an input shaft extending from the housing; a seal disposed within the housing and positioned about the input shaft; and a seal guard member positioned about the input shaft and mounted to the housing at an interface between the input shaft and the housing, wherein the seal guard member is configured to allow rotation of the input shaft without rotating therewith.

A self-aligning mud pump apparatus is provided. In one embodiment, the mud pump includes a rotatable crankshaft, a crosshead, a crosshead guide, and a hub disposed in a housing. The hub is disposed on the crankshaft and is operable to convert rotating motion of the crankshaft to reciprocating motion of the crosshead within the crosshead guide. The hub is coupled to the crosshead via a connecting rod, which is connected the crosshead such that the connecting rod has five degrees of freedom with respect to the crosshead guide. The mud pump may also or instead include a piston coupled to the crosshead with five degrees of freedom between the piston and the crosshead. Additional systems, devices, and methods are also disclosed.

A fracturing and power generation switchable apparatus, a well site, a control method of the well site, a control device, and a storage medium are provided. The fracturing and power generation switchable apparatus includes a power device, a speed transmission device, and a bearing base. The switchable apparatus is configured to switch between a first state and a second state, under the first state, the plunger pump is fixed on the bearing base and is connected with the speed transmission device, and the switchable apparatus is supplied as a fracturing apparatus, and under the second state, the electric generator is fixed on the bearing base and is connected with the speed transmission device, and the switchable apparatus is supplied as a power generation apparatus.

Systems and methods for supplying lubricating oil to a high-pressure fuel pump of an engine fuel system. In one embodiment, a system may include a plurality of channels routing lubricating oil to a gear system and drive shaft of a pump without flowing an entire volume of the lubricating oil through a cavity of the drive shaft.

An electric drive hydraulic fracturing pump system includes one or more electric motors, with each electric motor electrically coupled to a dedicated dual inverter to control operation of the motor. A plurality of electric motors may be coupled to each end of a pump crankshaft and configured to provide rotational power to the power end of a hydraulic fracturing pump through a planetary gearset coupled to each end of the crankshaft. A hydraulic cooling circuit having a first and second cooling systems may be used to regulate the temperature of the electric motors and dual inverters.

An electric drive hydraulic fracturing pump system includes one or more electric motors, with each electric motor electrically coupled to a dedicated dual inverter to control operation of the motor. A plurality of electric motors may be coupled to each end of a pump crankshaft and configured to provide rotational power to the power end of a hydraulic fracturing pump through a planetary gearset coupled to each end of the crankshaft. A hydraulic cooling circuit having a first and second cooling systems may be used to regulate the temperature of the electric motors and dual inverters.

A system for energy recovery from a rod pump includes a reversible hydraulic pump; a variable speed reversible motor-generator connected to the reversible hydraulic pump; and a variable speed drive that operates the motor-generator to rotate the reversible hydraulic pump in a forward direction to pump hydraulic fluid to the rod pump during an upstroke, and to operate the motor-generator in a generator mode in which a weight of a rod string lowers a piston in the rod pump during a downstroke to pump hydraulic fluid to rotate the hydraulic pump in reverse such that the motor-generator generates electricity, and the variable speed drive modulates a speed of the motor-generator during the downstroke to modulate a speed of the reversible hydraulic pump to control a rate of flow of hydraulic fluid through the reversible hydraulic pump and thereby modulate a rate of downward motion of the rod string.