Methods and systems for pumping fluid through tubing are provided. Methods include orbiting one or more first rollers at multiple angular speeds around the periphery of a substantially circular first disk having a first radius with each first roller travelling at the same angular speed as the other first rollers, orbiting second rollers at a second angular speed around a substantially circular second disk having substantially the first radius, and increasing the pressure of fluid in tubing between one first roller and one second roller by causing the one or more first rollers to orbit at a first angular speed greater than the second angular speed so the one first roller moves along and fully compresses the tubing in a first section of the first disk, and simultaneously causing the one second roller to move along and fully compress the tubing in a first section of the second disk.

A method for determining cavitation in a pump is disclosed. The method includes detecting, by a sensor, a pressure of a fluid pumped by the pump and determining, by a controller, whether the pressure exceeds a pressure range. Cavitation is determined when the pressure exceeds the pressure range. The method includes selectively incrementing or decrementing, by the controller, a counter value of a counter based on determining whether the pressure exceeds the pressure range. The counter value is incremented when the pressure exceeds the pressure range, and decremented when the pressure does not exceed the pressure range. The method includes determining, by the controller, whether the counter value exceeds a threshold value, and generating, by the controller, an alert when the counter value exceeds the threshold value and causing, by the controller, the alert to be displayed via a display.

A fluid transport system includes at least one flow control device and a multiphase pump configured to transport fluid. At least one pump sensing device is configured to measure at least one operating characteristic of the multiphase pump. A controller is programmed with a pump map including a correlation of the at least one operating characteristic of the multiphase pump with at least one operating characteristic of the fluid. The controller is configured to determine an estimated value of the at least one operating characteristic of the fluid based on the measured value of the at least one operating characteristic of the multiphase pump and the pump map. At least one regulating device coupled to at least one flow control device is modulated based on the estimated value of the at least one operating characteristic of the fluid.

Backlash in a precision system such as a pumping system can be reduced or eliminated with an anti-backlash device that has a first nut coupled to and fixed in relation to a piston. The first nut and a second nut may engage with a lead screw of a motor driving the piston. Relative rotation between the first and second nuts are limited or prevented. A biasing member maintains a spaced relationship between the first and second nuts along the lead screw such that the first nut remains in engagement with the lead screw to thereby reduce or eliminate backlash when the lead screw is rotated by the motor.

A pumping system with a pressure sensor positioned on the fill side and a pressure sensor on the dispense side to obtain and provide pressure information that can be used by a controller in determining various operating profiles. To avoid trapping air in a process fluid, a pressure sensor can be flush mounted or mounted at an angle on the sidewall of a feed chamber, a bottle, or a reservoir tank at or near the bottom or half-height. The pressure information obtained from the fill side can have many beneficial including filtration confirmation, air detection, and reduced pressure priming of a filter. The pumping system may further include a graphical user interface for displaying the operating profiles and various associated alarms in real time.

A method of controlling an auxiliary pump for supplying the hydraulic fluid of a hybrid transmission of a vehicle. The auxiliary pump, after the expiration of a predetermined time interval of deactivation, is activated to prevent accumulation of air in the intake area of the auxiliary pump. In addition, a device for the execution of the method, in which a control device is provided which has its signals connected with the electric auxiliary pump for the purpose of controlling the auxiliary pump in order to prevent accumulation of air in the intake area of the auxiliary pump.

A suction pressure acquisition unit acquires pressure data indicating pressure of a pump. A variation coefficient calculation unit calculates a variation coefficient indicating amplitude of pressure magnitude of the pump on a basis of the pressure data acquired by the suction pressure acquisition unit. An adjustment unit performs adjustment detection information that includes the variation coefficient calculated by the variation coefficient calculation unit, by using a pressure transmission coefficient representing ease of transmission for pressure of the pump. The detection information is used for cavitation occurrence detection. A determination unit 125 detects cavitation occurrence in the pump on a basis of the detection information adjusted by the adjustment unit.