Context
Aerostatic bearings

The lubricant most often used in aerostatic thrust bearings is air, which has the advantage of being readily available. This remark is perfectly true for aerodynamic thrust bearings, but needs to be weighed against aerostatic lubrication: the presence of a supply circuit comprising a compressor and filtering, de-oiling and dehumidification systems is essential. However, such supply circuits are commonplace, and the use of air instead of another gas removes the need for sealing systems, whose service life is often limited. A classic example of a product integrating the drive turbine, guide bearings and axial stop on the same shaft is the dental turbine. Examples could continue with machining or painting spindles.

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