Abstract: Magnetic fluid sealing ring is usually made up of permanent magnet which is polarized axially. New type magnetic sealing ring is designed using a permanent magnet polarized in radial direction. The construction and working principle of new type sealing ring are presented. Using finite element to analyze method, the magnetic fields of new type magnetic sealing ring and traditional type are analyzed. The distribution figures of the magnetic fields are shown. The sealing abilities are calculated. And the two types of magnetic fluid sealing rings are experimented. The magnetic fluid sealing rings made up of 1, 2, and 3 stages are tested respectively. The experiment and simulation results are given. The results show that compared with traditional magnetic fluid sealing ring, new type magnetic fluid sealing ring using a permanent magnet polarized in radial direction has a small size, simple construction and high sealing ability

Key words: Magnetic fluid, Seal, Sealing ability