A screw rotor is made out of polymer. The screw rotor includes a shaft with a rotor body on it. The polymer of the shaft is reinforced with fibers. The shaft features elements that engage the rotor body or corresponding elements on the rotor body, such that the elements prevent an axial and/or rotational movement of the shaft with respect to the rotor body.

The invention relates to a rotary vane vacuum pump comprising a housing member whose inner wall defines at least one pumping space, and a rotor that is arranged for rotation in the pumping space and has a rotor member and at least one vane, wherein the vane projects radially beyond the rotor member and together with the inner wall of the housing body a pumping volume that can be pumped by rotation of the rotor from an inlet to an outlet of the rotary vane vacuum pump, wherein the vane, at least in a region cooperating with the inner wall, comprises a polytetrafluoroethylene material containing polyimide particles and manufactured by hot pressing and sintering, and wherein the inner wall has a slide layer at least in a region cooperating with the vane, said slide layer comprising an oxide layer formed by anodic oxidation in an electrolyte including oxalic acid.

A polymeric composite insert component for a scroll compressor comprises a polymer and at least one reinforcing or lubricating particle. The insert component comprises an annular body and an axial projection. The annular body comprises a first annular inner surface defining a first centrally-disposed opening having a central axis. The annular body has a first side configured to engage a partition plate and a second side configured to engage a floating seal assembly. The axial projection extends from the first side of the annular body. The axial projection is configured to engage the partition plate. The insert component is configured to fluidly seal first and second interfaces during operation of the compressor. The first interface is defined between the first contact surface and the partition plate. The second interface defined between the second contact surface and the floating seal assembly.

The present invention recites a method of fabricating a stator for a downhole motor, the method comprising the steps of providing a stator tube having an interior surface and applying a bonding agent to the interior surface of the stator tube. Additionally, a mandrel is positioned within the stator tube, the mandrel having an outer geometry that is complimentary to a desired inner geometry for the stator. Furthermore, a reinforcing material is introduced into the stator tube to fill space between the mandrel and the interior surface of the stator tube and subsequently solidified to bond the reinforcing material to the interior surface of the stator tube. The mandrel is then removed from the bonded stator tube and reinforcing material such that a stator is fabricated.

Swash plate 3, which is a sliding member, includes base material 31, and coating layer 31 that is formed on base material 31 and has a thickness of 10 m or more. Coating layer 31 includes binder resin 321 and solid lubricant 322, which is dispersed in binder resin 321 and has a c-axis orientation, and a relative c-axis intensity ratio of solid lubricant 321 in coating layer 32 is 80% or more.

In order to prevent deterioration in performance of an oil-free screw compressor and scuffing caused by rust, surfaces of both male and female rotors are coated with heat-resistance coatings containing a solid lubricant. A coating contains Polyimide resin to which Molybdenum disulfide, as a solid lubricant, and Aluminum oxide and Titanium oxide, as additives, are added. Accordingly, it is possible to realize a coating that is higher in heat resistance and longer in lifetime than a conventional one.