A uniaxial eccentric screw pump for rotating a rotor about its axis and revolving the rotor without involving complicated operations and control is provided. The uniaxial eccentric screw pump includes a rotor drive mechanism capable of revolving a rotor while rotating the rotor about its axis. The rotor drive mechanism includes a rotation power transmission member rotatable about a predetermined center axis, and a revolution track formation member capable of revolving a proximal shaft portion of the rotor while allowing rotation of the proximal shaft portion about its axis. The rotor drive mechanism distributes power output from the same motor in parallel and transmit the power to the rotation power transmission member and the revolution track formation member, enabling the rotation power transmission member and the revolution track formation member to rotate about their axes while being synchronized mechanically, and enabling the rotor to revolve while rotating about its axis.

The invention relates to an eccentric screw pump comprising at least one stator (1) made from an elastic material and a rotor (2) that is rotatable in the stator (1), wherein at least some regions of the stator (1) are surrounded by a stator casing (3), and the stator casing (3), as a casing split along its length, consists of at least two casing segments (19) and forms a stator clamping device by means of which the stator can be clamped against the rotor (2) in the radial direction, wherein the stator clamping device has one or more movable adjusting elements which work on the casing segments (19) to adjust and clamp the stator. Said pump is characterised in that the stator clamping device comprises one or more actuators which are connected to the adjusting elements or are equipped with adjusting elements for an automated advancement of the stator.

A stator assembly for a progressing cavity pump is provided. The stator assembly includes a number of stator laminates having a planar body defining a primary, inner passage and a number of outer passages, the outer passages disposed effectively adjacent the inner passage whereby the inner passage is at least partially defined by a band, wherein the band is outwardly flexible. The stator laminates are coupled to each other in a stack wherein the stator laminate body inner passages define a helical passage. The helical passage is a flexible helical passage.

An electrical submersible pump assembly has a thrust bearing mechanism with first and second thrust runners axially and rotationally secured to the shaft and located within a housing. First and second thrust receiving structures are rigidly mounted in the housing to receive thrust from the first and second thrust transferring devices. A deflectable member located in the first thrust transfer thrust device decreases in axial thickness in response to thrust of a selected level. The second thrust transfer thrust device has an axial length less than an axial distance from the second thrust receiving structure to the second thrust runner, defining an initial axial gap. During operation of the pump, the shaft and the first and second thrust runners move axially a limited extent, closing the gap and transferring thrust from the second thrust transfer device to the second thrust receiving structure.

An electrical submersible pump assembly has a thrust bearing mechanism with first and second thrust runners axially and rotationally secured to the shaft and located within a housing. First and second thrust receiving structures are rigidly mounted in the housing to receive thrust from the first and second thrust transferring devices. A deflectable member located in the first thrust transfer thrust device decreases in axial thickness in response to thrust of a selected level. The second thrust transfer thrust device has an axial length less than an axial distance from the second thrust receiving structure to the second thrust runner, defining an initial axial gap. During operation of the pump, the shaft and the first and second thrust runners move axially a limited extent, closing the gap and transferring thrust from the second thrust transfer device to the second thrust receiving structure.

A progressing cavity pump operated by a motor is provided. In one embodiment, a system includes a motor, a progressing cavity pump having a rotor and a stator, and a fluid coupling that connects the motor to the progressing cavity pump. The fluid coupling includes an input turbine and an output turbine disposed within a housing. The motor is connected to the input turbine of the fluid coupling and the rotor of the progressing cavity pump is connected to the output turbine of the fluid coupling to enable the progressing cavity pump to be operated by the motor via the fluid coupling to pump fluid through the progressing cavity pump. Additional systems, devices, and methods are also disclosed.

A stator for an eccentric screw pump with an internal hollow space with a helically coiled inner contour for accommodating a rotor. The stator includes a stator core arranged in a stator casing, which stator core includes at least two radially separable core parts. According to the invention, the at least two radially separable core parts are each made from a metallic material or a technical ceramic material. The stator casing is a stator tube and is made of a metallic material. The stator casing is shrink-fitted onto the stator core. The invention also relates to an eccentric screw pump and a method for producing a stator.

A mud motor stator or a pump comprising of a tubular outer portion; a number of lobes extending radially inwardly from the tubular outer portion, at least one of which comprises a skeletal structure and method for producing a mud motor stator or a pump comprising of placing material and bonding the material together in a pattern dictated by the design shape of the stator or pump.

Rotary positive displacement machines based on trochoidal geometry and including a helical rotor that undergoes planetary motion relative to a helical stator can be designed and configured so that the axial load or rotor pressure force is positive, negative, or neutral. In some embodiments, a change in axial load, caused by a change in differential pressure across the machine, can be used to trigger a change in a mechanical configuration of the machine.

A progressive cavity pump includes a sealed drive between the rotor and universal joint. The universal joint includes a socket configured to receive a drive shaft of the rotor. A cover, such as a locking nut, is disposed over the connection between the rotor and universal joint. Seals are retained in place by the locking nut to prevent abrasive materials from entering into the interface between the rotor and the universal joint.