Centrifugal extractor of non-contact journaled construction

Abstract

A centrifugal extractor of non-contact journaled construction is provided in which, even under the environments of corrosive gase and mist-like liquid such as nitric acid mist generated in the reprocessing of a spent nuclear fuel, no problem in corrosion or deterioration of parts occurs and high reliability is obtained, and operation is enabled for a long period of time free from maintenance. A rotorhoused in a rotor housingis journaled by a main shaftand rotated and driven by a motor. The main shaft is surrounded by a drive-portion housing, and has a thrust magnetic diskon the upper end and radial magnetic disksand a motor-rotor portionin the circumference thereof. Thrust bearing electromagnets, radial bearing electromagnetsand a motor stator portionare incorporated into the drive-portion housing, and covered by non-magnetic anticorrosive protective plates, and a protective pipe, the motor-rotor portion being also covered by a protective can. Slide bearingsfor touch down made of fluorocarbon resin are disposed on the upper end of the main shaft and on the inner wall of the drive-portion housing in the vicinity of the upper end of the rotor.