The disclosure relates to a position detection device for determining the position of the diaphragm or the drive piston of an electric-motor-driven diaphragm pump, in particular detecting the upper and lower reversal point (Po, Pu) in the movement curve of the diaphragm of a diaphragm pump operated in an electric-motor-driven manner via eccentric means, wherein a diaphragm actuated by a drive connecting rod closes a conveying chamber with valve means provided on an inlet and outlet side such that the volume can be changed between a minimum and maximum volume, whereby a reciprocating movement of an electric motor having a rotor attached to a shaft is converted into an actuation movement of the drive connecting rod via the effect of the eccentric means, wherein the position detection device has detecting means for detecting the average value position of the rotor shaft, as well as an evaluation device in order to determine at least the position of the upper reversal point of the diaphragm from the average value position.

Various embodiments include methods for operating a high-pressure pump comprising: driving a piston arranged in a compression chamber with a motor shaft; during movement of the piston toward the top dead center, closing the inlet valve so the fluid is then delivered by the piston through an outlet valve; applying a coil current to an electromagnet used to close the inlet valve during and/or after overshooting the top dead center; detecting a start time at which the coil current, on account of starting of an opening movement of the inlet valve, fulfills a predetermined change criterion; labelling a dead center rotation position of the motor shaft at which the piston is at the top dead center based at least in part on the ascertained start time; and adjusting operation of the pump based on the identified dead center rotation position.

The embodiments herein relate generally to subterranean formation operations and, more particularly, systems and methods for achieving target downhole pressures having target downhole wave shapes for enhancement of subterranean formation stimulation and production. In particular, a treatment fluid is introduced into a subterranean formation and a downhole pressure wave in the subterranean formation having a downhole wave shape is determined, and a surface pressure wave having a surface wave shape is determined. The downhole wave shape and the surface wave shape are compared, followed by adjustment of the surface pressure to achieve a target downhole pressure wave in the subterranean formation having a target downhole wave shape. The target downhole pressure and target downhole wave shape may be selected to maximize production of the subterranean formation.

Certain conditions or triggering events require preventing or throttling the discharge of a servicing fluid from a pump to a wellhead or a borehole. Powering down may not be desirable or may require a duration that allows the condition or triggering event to persist. Selectively and automatically activating one or more pressure control valves may throttle or prevent the servicing fluid from being pumped from the pump during the power down sequence or without requiring a power down sequence. Selective activation of a pressure control valve may introduce pressurized fluid into a cylinder of the pump extending a rod to force or maintain a suction valve in an open position. While the suction valve is in the open position, the stroke of the plunger may not create enough pressure to pump the servicing fluid causing the servicing fluid to flow between a fluid header and a chamber of the pump.

Non-limiting exemplary embodiments of a pumping system and methods for operating the pumping system in a region of high pressure or a region of high flow are disclosed. The pumping system includes a piston disposed within a piston cylinder, a drive shaft, an eccentric coupled to the drive shaft, a connecting arm having opposing first and second ends, and a controller for controlling the rotation of the drive shaft such that the piston oscillates within a region of high pressure or a region of high flow.

Devices, systems, and methods for detecting properties of motion of at least one component of fluid exchange devices, such as, for example, a pressure exchange device or system.

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.

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.

An axial piston machine is capable of suppressing a sudden change in hydraulic pressure in a piston oil chamber upon start and stop to enable the axial piston machine to start and stop smoothly. The axial piston machine includes: a cylinder block including a rotation axis and a plurality of piston oil chambers disposed around the rotation axis; pistons housed in the plurality of piston oil chambers, respectively; and orifices formed in the cylinder block that allow fluid communication between each of the piston oil chambers and an outside of the cylinder block. The orifices are positioned to be opened when the movable swash plate is in the neutral position and to be closed when the movable swash plate is in the operating position. The orifices are closed by outer peripheral surfaces of the pistons when the pistons approach a top dead center position.

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.