A screw-spindle pump comprising: first and second screw spindles forming running and drive spindles, respectively, and a pump housing configured to receive the first and second screw spindles. The first and second screw spindles form, with at least the pump housing, delivery chambers, moving from a suction side to a pressure side of the pump as a consequence due to rotation of the screw spindles. The pump housing has an elongate insert, as an abutment for the first and second screw spindles and against which the first and second screw spindles are supported, the elongate insert having a first portion forming a first abutment for the second screw spindle and a second portion forming a second abutment for the first screw spindle. The elongate insert is clamped into a receptacle of the pump housing using a cross-sectional dimension of the elongate insert.

The pump device includes a motor portion that includes a shaft rotating about a central axis and a pump portion that is driven by a motor portion via the shaft. The pump portion includes a pump rotor that rotates along with the shaft and a pump housing that includes an accommodation portion that accommodates the pump rotor. The pump housing includes a pump body that includes a first bearing portion that supports the shaft and a pump cover with an accommodation portion disposed between the pump cover and the pump body. The pump cover includes a flow path through which oil is discharged and suctioned, and includes a second bearing portion that rotatably supports the shaft and that communicates with the flow path. An end portion of the shaft on one side in the axial direction is disposed at the second bearing portion or inside the flow path.

A rotary pump, preferably a vacuum pump, featuring: a delivery space including an inlet on a low-pressure side and an outlet on a high-pressure side of the pump; a rotor which is arranged in the delivery space and delivers a fluid from the inlet into the delivery space to the outlet from the delivery space; at least one housing part which delineates the delivery space at least axially; and a drive shaft which is connected in drive terms to the rotor; including at least one sealing element which is connected, secured against shifting and/or rotating, to the drive shaft and/or rotor and forms a radial sealing gap with the housing part.

The invention is based on pump system (10), in particular a self-suction pump system, with a liquid conveying unit (12) for conveying a liquid (56) and with a vacuum pump unit (14) which is, at least in an initial operation state, configured to supply the liquid conveying unit (12) with the liquid (56).

In order to improve a construction, it is proposed that at least in the initial operation state, the vacuum pump unit (14) is configured to transport a gas along the liquid conveying unit (12).

The invention includes a pump having a barrel, a plunger, a seal, a fluid conduit, and a motion drive. The barrel defines an elongated chamber. The plunger includes a tip, which is disposed in the chamber. The seal sealingly engages between the chamber and the plunger, and the motion drive is configured to rotate the chamber with respect to the plunger and to translate the tip within the chamber.

A method for calibrating a unit controller with a managing process determining a position of a decoupler mechanism on the pumping unit. The managing process can calibrate the unit controller with a dual pump mode in response to determining the decoupler mechanism is in a coupled position. The managing process can calibrate the unit controller with a single pump mode in response to determining the decoupler mechanism is in a decoupled position with the pumping unit operating with the first fluid end coupled to the power end and the second fluid end decoupled from the power end. The system controller can pump a wellbore treatment fluid in accordance with the pumping unit in i) the dual pump mode or ii) the single pump mode.

A diaphragm pump having a crankshaft that is rotatable about a rotational axis and coupled to a piston. The piston is reciprocally displaceable within a piston cylinder along an axis of motion between suction and discharge strokes. A diaphragm housing coupled to the piston cylinder at least partially defines a pumping chamber through which fluid is pumped as the piston reciprocates. The axis of motion, which intersects a connection between the piston and the connecting rod, may not intersect the rotational axis of the crankshaft such that, relative to an arrangement in which the axis of motion does intersect the rotational axis, a peak magnitude of piston side load forces during the discharge stroke is reduced and a peak magnitude of piston side load forces during the suction stroke is increased so as to attain an improved balance between the peak magnitudes of piston side load forces of the discharge and suction strokes.

A fluid machine includes a first rotor having a first rotor first working portion and a first rotor second working portion, a second rotor having a second rotor first working portion configured to mesh with the first rotor first working portion and a second rotor second working portion configured to mesh with the first rotor second working portion and rotate independently from the second rotor first working portion.

A hydraulic system includes a hydraulic gear pump with a first gear having a plurality of first gear teeth and a second gear having a plurality of second gear teeth. The hydraulic system also includes a control valve and a control circuit. The control circuit controls the pump to adjust at least one of a flow in the hydraulic system to a flow set point or a pressure in the hydraulic system to a pressure set point, and concurrently establishes an opening of the control valve to adjust at least one of the flow to the flow set point or the pressure to the pressure set point. The control circuit establishes a position of a first tooth relative to a position of a second tooth to seal a fluid path from the outlet of the hydraulic gear pump to the inlet of the hydraulic gear pump.

A hydraulic system includes a hydraulic gear pump with a first gear having a plurality of first gear teeth and a second gear having a plurality of second gear teeth. The hydraulic system also includes a control valve and a control circuit. The control circuit controls the pump to adjust at least one of a flow in the hydraulic system to a flow set point or a pressure in the hydraulic system to a pressure set point, and concurrently establishes an opening of the control valve to adjust at least one of the flow to the flow set point or the pressure to the pressure set point. The control circuit establishes a position of a first tooth relative to a position of a second tooth to seal a fluid path from the outlet of the hydraulic gear pump to the inlet of the hydraulic gear pump.