A double-action piston pump of an application system for applying a fluid medium to a substrate, wherein the piston pump has a piston which is movable between a first reversal point and a second reversal point for delivering the fluid medium, wherein on reaching the first reversal point and the second reversal point, the movement direction of the piston is reversed, wherein during an output period, the fluid medium is output by means of an output device, and during an interruption period, an output of the fluid medium by means of the output device is interrupted, wherein during the interruption period, the movement direction of the piston is reversed, wherein on reversal of the movement direction during the interruption period, the piston is situated at an intermediate position between the first reversal point and the second reversal point.

The disclosure relates to a coating agent pump for conveying a coating agent in a coating installation, in particular for conveying paint in a painting installation, with an electric drive motor for driving the coating agent pump so that the coating agent pump continuously changes its pump position during operation. The disclosure provides a position measuring system for quantitatively detecting the pump position of the coating agent pump.

A monitor and control system for a hydraulic fracturing pump is described herein to reduce or eliminate harmful oscillations in fluid discharge pressure caused by the pump load dynamics. The monitor and control system receives various sensor data from the operation of the pump, including the pump crank position, and executes a pump control equation or model based on the pump sensor data, pump load data and/or pump speed data. Pump control equations or models are specific to the design and dynamic operation of the pump, incorporating the number of plungers, pump dynamics, motor lag and motor dynamics, etc. Using the pump control equations or models, the monitor and control system determines control commands for the pump motor to reduce or eliminate the oscillatory discharge pressure at the pump.

Operating a pumping system includes moving a pumping element to transition liquid through the pump, and determining a value based at least in part upon inlet pressure and pumping speed that is indicative of a pressure of the liquid within a bore susceptible to cavitation. Pumping speed and/or inlet pressure can be varied responsive to the determined value to limit cavitation.

An infusion system includes a double action infusion pump. The pump includes a cylinder and a reciprocating piston received within the cylinder, the reciprocating piston separating a first pump chamber from a second pump chamber of the cylinder. A reciprocating motor is coupled with the reciprocating piston, and the first and second pump chambers alternate between filling and evacuating conditions with reciprocation of the reciprocating piston through operation of the reciprocating motor, and the speed of reciprocation is varied to provide a continuous output of fluid between the first and second pump chambers. A fluid source and a catheter are optionally coupled with the double action infusion pump. The catheter includes one or more infusion ports near a catheter distal portion, and the one or more infusion ports receive and expel the continuous output of fluid from the double action infusion pump.

A compensating device for volumetric pumps, comprising: a storage tank (2) predisposed for being connected to the delivery line (O) of a pump (P) and to a source of pressurized gas (A); a control valve (3) arranged for opening or closing the connection between the tank (2) and the source of pressurized gas (A); a control module (4) connected to the control valve (3). The device comprises a level sensor (5) associated with the tank (2) for detecting a threshold level for a liquid within the tank (2) and connected to the control module (4) for transmitting to the module (4) at least one operating signal indicating a liquid level higher than the threshold level. The control module (4) is configured to determine the opening of the control valve (3) in the presence of said operating signal and to determine the closing of the control valve (3) in the absence of said operating signal.

An infusion system includes a double action infusion pump. The pump includes a cylinder and a reciprocating piston received within the cylinder, the reciprocating piston separating a first pump chamber from a second pump chamber of the cylinder. A reciprocating motor is coupled with the reciprocating piston, and the first and second pump chambers alternate between filling and evacuating conditions with reciprocation of the reciprocating piston through operation of the reciprocating motor, and the speed of reciprocation is varied to provide a continuous output of fluid between the first and second pump chambers. A fluid source and a catheter are optionally coupled with the double action infusion pump. The catheter includes one or more infusion ports near a catheter distal portion, and the one or more infusion ports receive and expel the continuous output of fluid from the double action infusion pump.

A method for detecting faults in a pump includes: monitoring suction pressure and discharge pressure time domain signals, filtering the monitored suction pressure time domain signals and the discharge pressure time domain signals via a band pass filter, performing Fast Fourier Transform on the filtered suction pressure time domain signals and the discharge pressure time domain signals for conversion to suction pressure frequency domain signals and discharge pressure frequency domain signals, respectively, performing root mean square calculations on the suction pressure frequency domain signals and the discharge pressure frequency domain signals, analyzing the root mean square suction pressure frequency domain signals and the root mean square discharge pressure frequency domain signals to determine a performance index, and comparing the performance index against a predetermined cavitation threshold to determine whether cavitation exists.

A control system and method of a VFD-based pump are disclosed. The control system controls an electric motor via a VFD, and the electric motor drives the pump. The control system comprises: an anti-ripple injection module for injecting an anti-ripple signal into a control path, the anti-ripple signal causing pressure ripples in the pump output to he at least partially cancelled. Further disclosed is a pump system, comprising: a VFD, an electric motor, and a pump, wherein the VFD comprises the control system stated above.

Operating a pumping system includes moving a pumping element to transition liquid through the pump, and determining a value based at least in part upon inlet pressure and pumping speed that is indicative of a pressure of the liquid within a bore susceptible to cavitation. Pumping speed and/or inlet pressure can be varied responsive to the determined value to limit cavitation.