A free-mold stator for a progressing cavity pump can comprise a housing include an inner housing surface defining an uninterrupted helical profile, and a liner including an inner liner surface and an outer liner surface. The inner liner surface and the outer liner surface can each define an uninterrupted helical profile, and the inner housing surface of the housing can be adapted to receive the outer liner surface to prevent lateral and rotational movement between the liner and the housing.

A scroll compressor includes a plurality of fixing protrusions that are provided spaced apart from each other in a key that constitutes an Oldham ring, and an orbiting scroll, to which the key is coupled, or a ring body of the Oldham ring may be provided with a plurality of fixing grooves which are spaced part from each other and into which the plurality of fixing protrusions are respectively inserted and fixed.

A compressor is provided and may include a shell, a hub, an insert, and at least one collar. The hub may be disposed within the shell and define an axis of rotation. The hub may include an axially extending aperture. The insert may be disposed within the aperture. The at least one collar may be disposed about the hub.

The non-lubricated compressor (10) for compressing a gas, comprises: a stationary stator (12) with a housing (18) comprising a rotor cavity (20) delimited by a bottom wall (22), a top wall (24), and a lateral wall (26) connecting said bottom wall (22) and said top wall (24), a rotor element (14) arranged for rotation about an axis (z) within the rotor cavity (20) for compressing a gas therein, a self-supporting sealing element (16) arranged within the rotor cavity (20), wherein the sealing element (16) is made of an abradable carbon material, and comprises a wall portion (34) arranged on an inner surface of the lateral wall (26) of the rotor cavity (20).

A rotary engine rotor and a method for supplying rotary engine rotors are provided. The rotary engine rotor has a center axis, a rotor body, a plurality of peripheral surfaces, and a plurality of recess members. The rotor body has a central bore that extends along the center axis. The plurality of peripheral surfaces are disposed around an exterior perimeter of the rotor body. Each of the plurality of recess members are disposed in a respective one of the plurality of peripheral surfaces. Each recess member includes an interior cavity open to an exterior of the rotor.

A submersible multi-stage labyrinth-screw pump, having a rotor shaft; an end seal for the rotor shaft; an axial unloading unit integrated into the end seal of the rotor shaft; a lower radial bearing; a longitudinal channel, which connects a high-pressure zone at an exit for the rotor and the chamber of the axial unloading unit of the shaft, the axial unloading unit comprising a thrust block with a wear-resistant insert, a thrust collar, mated with a segment of the end seal, the end seal housing, a spring, a thrust ring, and a seat sleeve of the end seal, wherein the end seal of the rotor shaft's axial unloading unit operates as follows, when high pressure appears in the chamber of the rotor shaft's axial unloading unit, the fluid is kept from unproductive flows by hermetic contact of the ground insert of a segment and a seat of the end seal.

A method and apparatus to increase the labyrinth screw pump life, achieved by a decrease in axial forces in thrust tribo-couplings by creating a chamber into which high pressure at the exit from the stage is transmitted through the additional holes of the rotor, thereby creating an opposite axial force, which reduces the contact pressure on the friction surface of the thrust bearing.

An eccentric screw pump with a rotor (2) and with a rotationally fixed stator (6; 6) surrounding the rotor (2). The rotationally fixed stator includes at least one elastomeric portion, wherein a pressure chamber (16) is arranged on this elastomeric portion of the stator (6; 6) at a side facing away from the rotor (2). The pressure chamber (16) is connected to a pressure region of the eccentric screw pump such that the at least one elastomeric portion of the stator (6; 6) is subjected to a pressure produced by the eccentric screw pump.

It is intended to provide a vacuum pump so that without upsizing the vacuum pump, noise and vibration are reduced, heat dissipation property is secured, and the casing is downsized. Therefore, at least one turning part is provided in an exhausting path formed in a casing body. The casing body is formed of a material whose thermal conductivity is higher than that of a rotor and vanes, and a cylinder part where the vanes slide is press fitted in the casing body.

It is intended to provide a vacuum pump so that without upsizing the vacuum pump, noise and vibration are reduced, heat dissipation property is secured, and the casing is downsized. Therefore, at least one turning part is provided in an exhausting path formed in a casing body. The casing body is formed of a material whose thermal conductivity is higher than that of a rotor and vanes, and a cylinder part where the vanes slide is press fitted in the casing body.