Agitator seal

摘要

The invention relates to an agitator seal for chemical engineering equipment closed off from the outside atmosphere, which agitator seal is free-running without the use of a lubricant, does not have a tendency to jam in prolonged operation, is corrosion-resistant and, moreover, enables the agitator shaft to be supported in an axial direction. The agitator shaft is mounted by means of two ball bearings essentially composed of non-metallic materials within the bearing casing and channel-shaped recesses designed as a running surface for the balls of the ball bearings are arranged on the inner surface of the bearing casing in the region of the respective end sections of the bearing casing. The end sections of the bearing casing are preferably designed as a laboratory-glass planar flange. Borosilicate glass 3.3 is recommended as a material for the inner rings of the ball bearings and for the bearing casing, and ruby is recommended for the balls. The balls are guided in a two-piece guide cage made of titanium or of chemically resistant plastic such as graphite-powder filled polytetrafluoroethene.