A high pressure pump including a linear actuator having a servo motor to axially rotate a hollow rotor shaft in alternating directions, the servo motor having a stator positioned co-axially around the hollow rotor shaft with an interior of the rotor shaft being co-axially coupled to a drive member to convert axial rotation into reciprocal displacement, the drive member being constrained against linear movement and supporting a shaft. At least one piston is coupled to the shaft and the piston is arranged within a cylinder to define a pumping chamber, whereby alternating rotation of the rotor shaft causes reciprocal linear displacement of the piston to pressurize fluid in the pumping chamber. A drive mechanism includes a controller coupled to a servomotor and an encoder to measure movement of the hollow rotor or output shaft and send a feedback signal proportional to the movement to the controller.

Systems are provided comprising at least one driving cylinder comprising a driving chamber and a driving piston within the driving chamber. The driving piston separates the driving chamber into a driving fluid zone for receiving a driving fluid and a buffer zone for receiving a buffer fluid. The driving piston is movable in the driving chamber by the driving fluid. The systems may also comprise a driven cylinder comprising a driven chamber and a driven piston moveable in the driven chamber. The driven piston is connected to and driven by the driving piston to move within the driven chamber. The driven chamber comprises an input port configured to receive a driven fluid at a first, lower pressure into the driven chamber and an output port configured to expel the driven fluid at a second, higher pressure from the driven chamber when the driven fluid is pressurized by the driven piston. The buffer fluid is different from the driving fluid and the driven fluid, and the buffer fluid in the buffer zone separates the driving fluid from the driven fluid.

A method monitors the state of a device having a first drive cylinder for receiving hydraulic fluid and a first drive piston which is movably arranged in the first drive cylinder. The method determines a speed of the first drive piston, establishes a difference between the determined speed of the first drive piston and an expected speed of the first drive piston, and determines a faulty state as a function of the difference established between the determined speed of the first drive piston and the expected speed of the first drive piston.

A control method and a control device applied to an electric fracturing apparatus are provided. The electric fracturing apparatus includes a plunger pump and a first motor configured to drive the plunger pump, and the method includes: acquiring a preset displacement of the plunger pump; acquiring a rotation speed of the first motor and a discharge pressure of the plunger pump; determining a real-time displacement of the plunger pump based on the rotation speed of the first motor and the discharge pressure of the plunger pump and adjusting the real-time displacement; and upon the real-time displacement reaching the preset displacement, allowing the first motor to be kept in a stable operation state.

Methods and systems are provided to adaptively control a hydraulic fluid supply to supply a driving fluid for applying a driving force on a piston in a gas compressor, the driving force being cyclically reversed between a first direction and a second direction to cause the piston to reciprocate in strokes. During a first stroke of the piston, a speed of the piston, a temperature of the driving fluid, and a load pressure applied to the piston is monitored. Reversal of the driving force after the first stroke is controlled based on the speed, load pressure, and temperature.

A controller for operating a rod pumping unit at a pump speed. The controller includes a processor configured to operate a pump piston of the rod pumping unit at a first speed. The processor is further configured to determine a pump fillage level for a pump stroke based on a position signal and a load signal. The processor is further configured to reduce the pump speed to a second speed based on the pump fillage level for the pump stroke.

The present invention concerns a method of controlling a liquid volume which can be conveyed with a metering pump in a given time, comprising the steps: a. providing an input signal for controlling the liquid volume which can be conveyed with the metering pump in the given time, and b.lLinking the input signal to an actuating signal which influences the liquid volume which can be conveyed with the metering pump in the given time so that a change in the input signal leads to a change in the actuating signal and thus a change in the liquid volume which can be conveyed. To react to individual process demands it is proposed according to the invention that linking in step b. is effected in such a way that a change in the input signal leads to a change in the liquid volume which can be conveyed with the metering pump in the given time, which change in the liquid volume is non-proportional to the change in the input signal.

Methods and systems are provided to adaptively control a hydraulic fluid supply to supply a driving fluid for applying a driving force on a piston in a gas compressor, the driving force being cyclically reversed between a first direction and a second direction to cause the piston to reciprocate in strokes. During a first stroke of the piston, a speed of the piston, a temperature of the driving fluid, and a load pressure applied to the piston is monitored. Reversal of the driving force after the first stroke is controlled based on the speed, load pressure, and temperature.

A method operates a construction material and/or viscous-material pump having: at least one conveying cylinder, the conveying cylinder being designed to receive and discharge construction material and/or viscous material; and at least one conveying piston, the conveying piston being disposed in the conveying cylinder for movement in order to draw construction material and/or viscous material into the conveying cylinder and to displace drawn-in construction material and/or viscous material out of the conveying cylinder. The method includes: conveying construction material and/or viscous material, by movement of the conveying piston in order to draw in and displace construction material and/or viscous material; sensing a position variable during the movement, the position variable characterizing a position of the conveying piston along its stroke in the conveying cylinder; sensing a conveying variable during the movement, the conveying variable being of a different type than the position variable and characterizing the conveying of construction material and/or viscous material by the pump; and determining a profile of a subsequent movement of the conveying piston by linking the sensed position variable and the sensed conveying variable to each other; and controlling the subsequent movement in accordance with the determined profile.

Provided for may be a motor speed control apparatus for use with a piston pump. The piston may be adapted to create a plurality of compressions and the piston may have a compression path and a decompression path. Further, the piston cylinder may include a proximal end, a distal end, and a piston length. The piston cylinder may have a proximal threshold position and a distal threshold position. In an embodiment, the apparatus includes a proximal and a distal hall effect sensor. The apparatus may comprise a computer, wherein instructions instruct the piston to decelerate at the distal threshold position during the compression path and the proximal threshold position during the decompression path, and/or wherein the computer executable instructions instruct the piston to accelerate at the distal threshold position during the decompression path and the proximal threshold position during the compression path.