Techniques are provided for protecting a rotary positive displacement pump, e.g., using a signal processor that receives signaling containing information about power, torque, speed, viscosity and specific gravity related to the operation of a pump; and determines whether to enter an enhanced pump protection mode for the rotary positive displacement pump based at least partly on a relationship between an actual corrected tune ratio and a tuned ratio set point (Tune Ratio SP). The signal processor may determine if the actual corrected tune ratio is less than or equal to the actual corrected tune ratio set point (Tune Ratio SP), and if so, then to enter the enhanced pump protection mode, else continues to use a basic pump protection mode, and also determines the actual corrected tune ratio based upon a ratio of an actual corrected power (PAcorr) divided by a tuned corrected power (PTcorr) at a specific operating speed.

Techniques are provided for protecting a rotary positive displacement pump, e.g., using a signal processor that receives signaling containing information about power, torque, speed, viscosity and specific gravity related to the operation of a pump; and determines whether to enter an enhanced pump protection mode for the rotary positive displacement pump based at least partly on a relationship between an actual corrected tune ratio and a tuned ratio set point (Tune Ratio SP). The signal processor may determine if the actual corrected tune ratio is less than or equal to the actual corrected tune ratio set point (Tune Ratio SP), and if so, then to enter the enhanced pump protection mode, else continues to use a basic pump protection mode, and also determines the actual corrected tune ratio based upon a ratio of an actual corrected power (PAcorr) divided by a tuned corrected power (PTcorr) at a specific operating speed.

A hydraulic pump is described, comprising at least one inlet duct for a fluid, at least one outlet duct for the fluid and at least one pumping unit interposed between the inlet and outlet ducts. At least one multifunction valve is interposed between the inlet duct, upstream of the pumping unit, and the outlet duct, downstream of the pumping unit, which valve is configured to divert the flow of fluid from the inlet duct to the outlet duct without the fluid flowing into the pumping unit. The multifunction valve comprises a valve body that defines an inner bypass channel in which a shutter element is axially movable, an actuator member operatively associated with the shutter element and configured to move it from a closing position to an opening position of the bypass channel, and an elastic contrast element operatively associated with the shutter element and configured to keep it in the first closing position of the bypass channel when such shutter element is not actuated by the actuator member. The actuator member consists of a bias spring manufactured with a shape memory alloy, configured to move the shutter element from the first closing position to the second opening position of the bypass channel when a predefined temperature value is reached.

A hydraulic pump is described, comprising at least one inlet duct for a fluid, at least one outlet duct for the fluid and at least one pumping unit interposed between the inlet and outlet ducts. At least one multifunction valve is interposed between the inlet duct, upstream of the pumping unit, and the outlet duct, downstream of the pumping unit, which valve is configured to divert the flow of fluid from the inlet duct to the outlet duct without the fluid flowing into the pumping unit. The multifunction valve comprises a valve body that defines an inner bypass channel in which a shutter element is axially movable, an actuator member operatively associated with the shutter element and configured to move it from a closing position to an opening position of the bypass channel, and an elastic contrast element operatively associated with the shutter element and configured to keep it in the first closing position of the bypass channel when such shutter element is not actuated by the actuator member. The actuator member consists of a bias spring manufactured with a shape memory alloy, configured to move the shutter element from the first closing position to the second opening position of the bypass channel when a predefined temperature value is reached.

There is disclosed a pump apparatus which can more accurately determine the occurrence of an abnormal vibration. The pump apparatus includes: a pump; an electric motor for driving the pump; an inverter as a speed changing means for the electric motor; a vibration detector for detecting at least one of a vibration of the pump, a vibration of the electric motor and a vibration of the inverter; and a controller for controlling the pump. The controller includes a storage unit for storing a measured vibration value measured by the vibration detector. The storage unit has a storage table which, when the rotational speed of the pump is increased stepwise to a predetermined rotational speed, stores the measured vibration value measured at each step.

A drilling motor system for drilling a subterranean well includes a stator tube, the stator tube being an elongated tubular member with a central stator bore. A stator elastomer layer is located within the central stator bore, lining a wall of the central stator bore. The stator elastomer layer has an elastomer bore that includes a plurality of stator lobes extending in a helical pattern along an axial length of the central bore. A rotor is located within the elastomer bore, the rotor being an elongated member that includes a plurality of rotor lobes extending in a helical pattern along an axial length of the rotor. The stator elastomer layer includes a failure detection system, the failure detection system operable to identify a region of damaged stator elastomer layer.

A method for conveying a fluid through a screw pump, wherein at least one drive spindle of the screw pump is driven by an asynchronous motor, wherein, the asynchronous motor is operated at a first nominal frequency, a gas/liquid mixture being conveyed as fluid, a measurable variable depending on a liquid content of the fluid is registered, and after a fulfillment of a frequency-change condition depending on the measurable variable the asynchronous motor is operated at a second nominal frequency, reduced in comparison with the first nominal frequency.

A method for conveying a fluid through a screw pump, wherein at least one drive spindle of the screw pump is driven by an asynchronous motor, wherein, the asynchronous motor is operated at a first nominal frequency, a gas/liquid mixture being conveyed as fluid, a measurable variable depending on a liquid content of the fluid is registered, and after a fulfillment of a frequency-change condition depending on the measurable variable the asynchronous motor is operated at a second nominal frequency, reduced in comparison with the first nominal frequency.

A progressive cavity pump (PCP) system includes a PCP with a rotor rotatably disposed in a stator, a permanent magnet motor, sucker rod(s), and a control system. The rotor is coupled to one of the sucker rods via a high-torque connection that allows for counter clockwise rotation without loosening the connection between the rotor and sucker rod. The control system operates the system in a production mode by rotating the rotor clockwise. Upon manual input by a user, or automatic triggering when protections settings of the control system call for a shutdown or cleanout or when the control system senses an imminent pump shutdown, the control system operates the system in a reverse mode by rotating the rotor counterclockwise. The reverse mode pumps fluids and suspended solid particles down into the well prior to pump shutdown to inhibit the solids from clogging the pump or preventing the pump from restarting.

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.