An engine (12) drives a variable capacity-type hydraulic pump (16), discharged hydraulic oil is selectively supplied to a cooling fan (19) and a hoist cylinder (11) in accordance with switching of a selection valve (17), thereby controlling the same on the basis of each target value. A pump discharge pressure (Pp) of the hydraulic oil discharged from the hydraulic pump (16) and a motor supply pressure (Pm) of the hydraulic oil supplied to a hydraulic motor (18) via the selection valve (17) are detected by sensors (27, 28) and are compared with pressure determination values stored in advance as a pump discharge pressure (Pp) and an actuator supply pressure (Pm) generated when the target value is achieved. Presence/absence of abnormality in the hydraulic actuator control device (15) is determined on the basis of a result of the comparison, and when abnormality is determined to have occurred, control is performed to minimize the capacity of the hydraulic pump (16).

Systems and methods for monitoring, detecting, and/or intervening with respect to cavitation and pulsation events during hydraulic fracturing operations may include a supervisory controller. The supervisory controller may be configured to receive pump signals indicative of one or more of pump discharge pressure, pump suction pressure, pump speed, or pump vibration associated with operation of the hydraulic fracturing pump. The supervisory controller also may be configured to receive blender signals indicative of one or more of blender flow rate or blender discharge pressure. Based on one or more of these signals, the supervisory controller may be configured to detect a cavitation event and/or a pulsation event. The supervisory controller may be configured to generate a cavitation notification signal indicative of detection of cavitation associated with operation of the hydraulic fracturing pump, and/or a pulsation notification signal indicative of detection of pulsation associated with operation of the hydraulic fracturing pump.

An inclined-axis axial piston machine includes a housing, a drive shaft and a cylinder barrel. The drive shaft is mounted in the housing so as to be rotatable with respect to a first axis of rotation and is integral with a flange. Each piston is coupled to the flange via a ball joint. A multiplicity of counting perforations are arranged in a periodically distributed and continuous manner over an outer circumferential surface of the flange. The housing accommodates a sensor arranged opposite the counting perforations such that rotation of the drive shaft causes a signal change at the sensor. Each counting perforation is formed integrally from the flange, in the form of a recess having a single continuous perimeter. A side wall of the recess, starting from the perimeter, extends uninterruptedly, without sharp bends or offsets, over the entire circumference of the perimeter.

A method controls the start-up of an oil pump of a gearbox by a brushless electric motor that has no position sensor. The stator coils are powered from the off mode in a constant-current open-loop control sequence until the pump reaches a speed threshold at which speed regulation switches over to closed-loop control on a setpoint corresponding to the lubrication flow rate required to ensure the reliability of the gearbox, but without in so doing exceeding a current threshold indicative of pump seizure, at which point motor control switches back over to the constant-current open-loop control sequence. The open-loop current setpoint is higher than the threshold for switching over to closed-loop control so that in the open-loop control mode the motor torque available at the pump is higher than in the closed-loop control mode.

System/method for real-time monitoring and control of pump operations at a well provide a pump control system that uses pump fillage with a proportional-integral-differential (PID) based algorithm to control positive displacement pump operations. The pump control system/method obtains measured or inferred pump speed from available pump speed data and, using certain pump characteristics provided by the well operator, calculates a theoretical fluid flow rate based on the pump speed. The pump control system/method thereafter compares the calculated theoretical fluid flow rate to a measured or observed fluid flow rate to calculate a pump fillage. The calculated pump fillage is then provided as a process input to the PID based algorithm along with a desired pump fillage from the well operator. The PID based algorithm processes the calculated pump fillage and the desired pump fillage using tuning parameters to determine an optimum pump speed based on the desired pump fillage.

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.

There is provided a technique that includes: a controller configured to execute a process recipe including a plurality of steps to perform a predetermined process on a substrate. The controller acquires device data, which includes at least one of a current value, a rotational speed, and a back pressure of a pump, in a specific step among the plurality of steps and compares an acquired value of the device data with a previously acquired value of the device data. The controller generates a notification if at least one of the following conditions is met: the acquired value for the current value is larger than the previously acquired value for the current value, the acquired value for the back pressure is larger than the previously acquired value for the back pressure, and the acquired value for the rotational speed is smaller than the previously acquired value for the rotational speed.

The present disclosure provides a device for monitoring oil pressure in an oil cylinder of a diaphragm compressor, including a piston rod and a strain gauge circuit. The strain gauge circuit includes a strain gauge component and a bridge circuit connected, and the strain gauge component is arranged on the surface of the piston rod. A strain gauge component is noninvasively arranged on the piston rod of the diaphragm compressor to measure the load of the piston rod, such that the oil pressure can be measured indirectly, and thus the oil pressure of the diaphragm compressor can be measured nondestructively. Nondestructive and noninvasive monitoring of the diaphragm compressor is safe and reliable, and can achieve accurate monitoring of the oil pressure especially in high-pressure working conditions.

An aircraft hydraulic control system includes a pump system, a fluid circuit, and a controller. The pump system includes a hydraulic pump and a ram air turbine assembly. The fluid circuit delivers hydraulic fluid to the hydraulic pump and receives the hydraulic fluid output from the hydraulic pump. The controller is in signal communication with the hydraulic pump. The controller determines a rotational frequency of a ram air turbine included in the ram air turbine assembly, and controls the hydraulic pump so as to control the flow of hydraulic fluid in the fluid circuit. The flow of hydraulic fluid in the fluid circuit controls a fluid pressure of the aircraft.

Systems and methods for monitoring, detecting, and/or intervening with respect to cavitation and pulsation events during hydraulic fracturing operations may include a supervisory controller. The supervisory controller may be configured to receive pump signals indicative of one or more of pump discharge pressure, pump suction pressure, pump speed, or pump vibration associated with operation of the hydraulic fracturing pump. The supervisory controller also may be configured to receive blender signals indicative of one or more of blender flow rate or blender discharge pressure. Based on one or more of these signals, the supervisory controller may be configured to detect a cavitation event and/or a pulsation event. The supervisory controller may be configured to generate a cavitation notification signal indicative of detection of cavitation associated with operation of the hydraulic fracturing pump, and/or a pulsation notification signal indicative of detection of pulsation associated with operation of the hydraulic fracturing pump.