TourTour Pneumatic cylinder with air lubricated piston bearing
High frequency precision pneumatic cylinder: piston diameter 50 mm, pressure supply 6 baro, radial load up to 500 N, bearing gap 10 Ám, gas consumption 5 liter/min. Total gas lubrication at maximum piston load 1200N, 10 liter/min.

The pneumatic cylinder is a good example where pressurized gas is already present and can also be used to eliminate the friction between the piston and the cylinder, in the same way as in a pressurized bearing.
 

Air is pressurized between the piston and cylinder wall via the porous surface ring (A). The pressurized surface of the piston (C), is separated from the pressurized piston bearing by a gab in the surface (B), connected to ambient pressure.
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