An apparatus can include a central member between a first fluid section and a second fluid section, wherein the central member, first fluid section, and second fluid section define a longitudinal axis thereon, at least one first fluid section driving member in mechanical communication with the central member, at least one second fluid section driving member in mechanical communication with the central member, an oscillating member in mechanical communication with the central member configured to oscillate the central member along the longitudinal axis, a pump inlet in fluid communication with a fluid source, and a pump outlet.

An apparatus can include a central member between a first fluid section and a second fluid section, wherein the central member, first fluid section, and second fluid section define a longitudinal axis thereon, at least one first fluid section driving member in mechanical communication with the central member, at least one second fluid section driving member in mechanical communication with the central member, an oscillating member in mechanical communication with the central member configured to oscillate the central member along the longitudinal axis, a pump inlet in fluid communication with a fluid source, and a pump outlet.

A submersible pumping system includes an electric motor and a pump driven by the electric motor. The pump includes a rotatable shaft driven by the motor, one or more piston assemblies configured for linear reciprocating motion and a mechanism for converting the rotational movement of the shaft to linear reciprocating movement in the piston assemblies. In one aspect, the mechanism for converting the rotational movement of the shaft includes a tilt disc assembly. In another aspect, the mechanism for converting the rotational movement of the shaft includes a camshaft assembly.

A method to dislodge debris from a pump system in which the pump system includes a down-hole pump coupled by a rod string to an above-ground pump actuator, which is coupled to a controller configured to operate the pump system, and where the actuator has an adjustable stroke length. The method also includes determining that the pump system should begin operating in a pump clean mode, implementing the pump clean mode configured in the controller, and cycling the pump actuator at a preset command speed using a preset starting stroke length, preset acceleration rate and a preset deceleration rate. The method also includes continuing to cycle the pump actuator while incrementally decreasing the stroke length by a preset stroke length increment resulting in increased pump cycling frequencies. Further, the method calls for determining that the pump clean mode is complete, and returning the pump system to a normal operation mode.

A pump supplying an application system of a liquid covering product including a motor actuating at least two pistons, a drum rotated by the motor, the drum including an outer cylindrical surface having a cam profile, each piston being secured to a rod on which a roller is fastened rolling over the cam profile such that the roller connected to each piston via one of the rods is translated along the translation axis of the corresponding piston under the action of the rotation of the drum, each roller being in contact with the cam profile in an angularly offset position relative to the other rollers such that one of the pistons is moving when the other piston reaches an inversion point of its movement direction, and the pump including compensating means suitable for accelerating one of the pistons when another piston reaches an inversion point of its movement direction.

A vibratory drive includes a pulse generator and at least one actuator. The actuator includes a first fluid chamber and a second fluid chamber, the volumes of which are adjustable in phase opposition. The first fluid chamber has a fluid connection to a third fluid chamber in the pulse generator. The second fluid chamber has a fluid connection to a fourth fluid chamber in the pulse generator. The third and fourth fluid chambers each have portions that are defined by linearly moveable defining elements. The pulse generator includes a rotor that rotates relative to a first axis of rotation and that defines respective portions of the third fluid chamber and the fourth fluid chamber. The defining elements are linearly moveable in the rotor. The pulse generator includes a coupling element that is separate from the rotor. The defining elements are coupled in their movement to that of the coupling element.

A method for manufacturing an at least sectionally spherical-cap-shaped recess on a drive shaft for a hydrostatic axial piston machine includes whirling of the recess and heat treatment of the recess to form a wear layer. A drive shaft for a hydrostatic axial piston machine includes at least one recess manufactured according to the method. A hydrostatic axial piston machine includes a drive shaft with at least one recess manufactured according to the method.

A method to dislodge debris from a pump system in which the pump system includes a down-hole pump coupled by a rod string to an above-ground pump actuator, which is coupled to a controller configured to operate the pump system. The method also includes determining that the pump system should begin operating in a pump clean mode, and implementing the pump clean mode configured in the controller. The method also includes impressing a preset vibration frequency during a portion of a pump stroke of at least one pump cycle. Further, the method calls for determining that the pump clean mode is complete, and returning the pump system to a normal operation mode.

A system for detecting an abnormality in hydraulic rotating equipment according to one embodiment includes: a sensor that measures a drain pressure of the hydraulic rotating equipment; and processing circuitry. The hydraulic rotating equipment is of an axial piston type and includes M pistons. The processing circuitry performs frequency analysis on a pressure waveform that is a result of measurement by the sensor to generate a frequency spectrum, and if a pressure amplitude of a rotational Mth-degree component in the frequency spectrum is less than a predetermined percentage of a pressure amplitude of a rotational first-degree component in the frequency spectrum, determines that the hydraulic rotating equipment is in a normal condition, whereas if the pressure amplitude of the rotational Mth-degree component is greater than the predetermined percentage of the pressure amplitude of the rotational first-degree component, determines that there is an abnormality in the hydraulic rotating equipment.

A system for detecting an abnormality in hydraulic rotating equipment according to one embodiment includes: a sensor that measures a drain pressure of the hydraulic rotating equipment; and processing circuitry. The hydraulic rotating equipment is of an axial piston type and includes M pistons. The processing circuitry performs frequency analysis on a pressure waveform that is a result of measurement by the sensor to generate a frequency spectrum, and if a pressure amplitude of a rotational Mth-degree component in the frequency spectrum is less than a predetermined percentage of a pressure amplitude of a rotational first-degree component in the frequency spectrum, determines that the hydraulic rotating equipment is in a normal condition, whereas if the pressure amplitude of the rotational Mth-degree component is greater than the predetermined percentage of the pressure amplitude of the rotational first-degree component, determines that there is an abnormality in the hydraulic rotating equipment.