CENTRIFUGALSEPARATOR MED ETT HOLJE AVTETAT MEDELST EN MEKANISK TETNING

The present invention relates to a centrifugal separator of the kind comprising a rotor (1), which is supported by a vertical driving shaft (2), a stationary casing (3), which surrounds the rotor (1) and has a bottom opening (5) through which the driving shaft (2) extends, a frame (4) which supports the casing (3) and is arranged to support radially in a resilient manner a radial bearing (6) for the driving shaft (2), and a mechanical seal with two sealing rings abutting axially against each other, one rotatable (11) and one non-rotatable (13), to seal the interior of the casing (3) from connection with the space surrounding the radial bearing (6) via the opening (5) in the bottom of the casing (3). In order to decrease the stresses on the radial bearing (6) and to provide for a more reliable sealing between the casing (3) and the housing of the mechanical seal, the non-rotatable sealing ring (13) is radially fixed relative to the casing (3), whereas the rotatable sealing ring (11) is arranged during operation to be moving radially relative to the non-rotatable sealing ring (13).