A collecting device for loosening and collecting debris in a well comprises a first and second end portions, a collecting receptacle between the first and second end portions having at least one receptacle section and at least one screen receptacle, and a motor. The device at its first end includes a feed pipe, a conveying screw in feed pipe driven by the motor and arranged to move the debris in towards the collecting receptacle, and a tool at the leading end portion of the conveying screw. A method described of loosening and collecting debris in a well by the collecting device.

A progressive cavity pump includes at least one of a jacketed stator casing and a jacketed inlet body. The jacketed stator casing includes a stator heating chamber, a stator assembly, and a rotor rotatably disposed within the stator assembly. The stator heating chamber forms a first space around the stator assembly and receives heating fluid therein. The stator assembly includes a cylindrical wall and a stator segment that forms a helically-convoluted chamber within the cylindrical wall. The jacketed inlet body includes an inlet heating chamber and a working fluid chamber in fluid communication with the helically-convoluted chamber. The inlet heating chamber forms a second space around the working fluid chamber and receives heating fluid therein. The stator heating chamber and the inlet heating chamber are isolated from each other, the helically-convoluted chamber, and the working fluid chamber.

A progressive cavity pump includes a torque input disposed on a rotational axis, a resilient stator cylinder, a screw rotor situated within the resilient stator cylinder, and a universal joint. The universal joint rotationally couples the screw rotor to the torque input, and includes a swivel block, a linkage, a universal joint coupler, and a fastener. The swivel block has opposite laterally extending trunnions. The linkage extends parallel to the rotational axis, and laterally captures the laterally extending trunnions. The universal joint coupler is disposed around the swivel block and adjacent the linkage. The fastener connects the universal joint to the swivel block. The fastener and the laterally extending trunnions cooperate to transmit torque about the rotational axis through the linkage, while permitting lateral translation of the universal joint coupler in a plane orthogonal to the rotational axis.

A device is provided for pumping fluid from a wellbore up to surface. The device includes a stator unit, a rotor unit run within the stator unit on a rod string, the rotor unit and the stator unit engaging with one another to form an annular space therebetween for passage of fluid. An upstream check valve on the rod string uphole of the rotor unit is moveable from an open position in which fluid is passable through the annular space, and a closed position in which fluid passage through the annular space is prevented. A hollow rod section extends through the rod string in fluid communication with the annular space both downstream and upstream of the upstream check valve, for entry of fluid into a downhole end of the hollow rod section, passage of fluid upstream therefrom and exit of fluids from an uphole end of the hollow rod section, back into the annular space. A method is further provided for pumping fluid from a wellbore after shutdown.

Sealing in rotary positive displacement machines based on trochoidal geometry that comprise a helical rotor that undergoes planetary motion within a helical stator is described. Seals can be mounted on the rotor, the stator, or both. The rotor can have a hypotrochoidal cross-section, with the corresponding stator cavity profile being the outer envelope of the rotor as it undergoes planetary motion, or the stator cavity can have an epitrochoidal cross-section with the corresponding rotor profile being the inner envelope of the trochoid as it undergoes planetary motion. In some embodiments, the geometry is offset in a manner that provides advantages with respect to sealing in the rotary machine. In multi-stage embodiments, the rotor-stator geometry remains substantially constant or varies along the axis of the rotary machine.

A transmission assembly includes a cavity in a female U-joint having a groove that extends radially outward from an inner diameter thereof and bounded by three planar drive surfaces. A male U-joint member includes a drive end includes a longitudinal rectangular extension protruding radially outward from a periphery and positioned within the groove of the cavity. The drive end includes a longitudinal rectangular insert has a portion forming the extension positioned within the groove and retained within the drive end. The extension includes (1) opposing longitudinal sides, each forming a side crest disposed between a pair of angular side surfaces that extend axially from the side crest inward toward a center of the extension, and (2) a top side forming a top crest disposed between a pair of angular top surfaces that extend axially from the top crest downward toward the center of the extension.

Rotary positive displacement machines based on trochoidal geometry that includes a helical rotor that undergoes planetary motion relative to a helical stator are described. The rotor can have a hypotrochoidal-based cross-sectional shape, with the corresponding stator cavity cross-sectional shape being the outer envelope of the rotor cross-sectional shape as it undergoes planetary motion, or the stator cavity can have an epitrochoidal-based cross-sectional shape with the corresponding rotor cross-sectional shape being the inner envelope of the stator cross-sectional shape as it undergoes planetary motion. Such machines can be configured so that the stator axis is spaced from the rotor axis, the rotor is configured to spin about its axis and the stator is configured to spin about its axis, and/or the rotor and the stator are held at a fixed eccentricity so that the rotor undergoes planetary motion relative to the stator, but does not orbit.

Problem: To provide a fluid transfer device that can solve an issue of pulsation that occurs when a liquid material is discharged from a nozzle by eccentrically rotating a male-screw-shaped rotor within a stator having a female-screw-shaped insertion hole, an application device including the fluid transfer device, and an application method. Solution: A fluid transfer device 1 includes: an outer cylinder 10; a stator 11 that has a female-screw-shaped insertion hole 12 as a through-hole and is provided on an inner periphery of the outer cylinder; and a male-screw-shaped rotor 20 that is connected to a rotor driving part and eccentrically rotates in contact with an inner periphery of the stator. In the fluid transfer device 1 capable of transferring a fluid in a transport path formed by the stator 11 and the rotor 20, by rotating the rotor 20 inserted through the insertion hole 12, contact force with the rotor 20 at an inlet portion and an outlet portion of the stator 11 is smaller than contact force with the rotor 20 at a central portion of the stator 11.

This disclosure relates to pumps and, more particularly, to progressive cavity pumps.

A full-metal anti-high temperature cycloid downhole motor comprises an outer tube, a stator, a rotor, a partition plate, a flow distribution disc, and a flow guide mechanism. The inside of the stator is provided with N grooves, the inner side walls of the N grooves form an annular inner contour surface; the rotor is formed with N−1 rotating heads provided along the axial direction of the outer tube, and each rotating head is provided with an embedding slot, one side of the embedding slot is provided with a notch, a rotor copper rod that can be in rolling engagement with the inner contour surface through the notch is provided in the embedding slot, and there is a changing gap between the outer wall of the rotor copper rod and the inner wall of the embedding slot.