Abstract: A bearing seal between the internal space of a centrifuge and its drive part utilizes, in a preferred embodiment, three similar sealing elements arranged in axial succession to each other and pressed against a protective bushing of the drive shaft in an elastic manner. The protective bushing of the drive shaft has a reduced diameter in the contact area of the sealing element closest to the internal space of the centrifuge, so that protective gas introduced into the space between the sealing elements and the subsequent sealing elements flows into the internal space of the centrifuge.

Abstract: A centrifugal filter has a centrifuge drum rotatable about an axis and provided with a plurality of sieve support plates lining the drum. Each of the plates is generally flat and rectangular and has a radially inwardly directed inner face. They are each formed with an array of flow grooves extending on and opening radially inwardly at the inner face and each having an outer end and an inner end spaced along the plate therefrom. The flow grooves are of increasing flow cross section from their outer ends to their inner ends. An outlet serves for draining liquid from the inner ends. A filter medium overlies the inner face over the flow grooves. Thus flow is maintained substantially uniform even at the outer groove ends, where relatively little filtrate moves. As a result clogging of these flow grooves is impossible; they will stay clear along their entire lengths.