Currently there are two main rotary shaft sealing solutions installed on coal mine motors, one is the non-contact IP66 labyrinth Isolator, and the other is the IP67 structural design that can be operated in submerged working conditions.

The traditional IP66 structure is non-contact, relying on the centrifugal force of the rotor ring to retain the water or dust dust entering into the labyrinth outside and discharge out from the purge hole at the bottom position. Labyrinth design is suitable for high speed, but can not be applied to the submerged conditions.

In the past time, the IP67 seal of the rotary shaft of the explosion-proof motor, is a combination of rubber lip seal and labyrinth seal. This combination will take up a lot of space, and at the same time, due to the high rubber friction coefficient, the OEMs have to reduce the preload of the rubber lip seal to prevent fast temperature increasing. Such structure can be operated underwater for a short period of time before the sealing lips wear out, but in harsh environment full of dust and particles, the rubber sealing lips will wear out and leak quickly, which will eventually lead to the failure of the combination design.

The BRS patented IP67 structure combines the advantages of PTFE oil seals, magnetic oil seals and labyrinth labyrinths, which has solved the problems of scratching on the shaft, short working life, and small adaptive range of radial run out of the shaft with the lip seal.

IP67 Bearing Isolator is comprised with a rotor ring which has been processed with hardening treatment, a copper static ring installed into the housing via the interference fit press-fit, ensuring that the installation firm enough, a double-lipped PTFE lip seal which is embedded between the rotor and static rings, and the sealing lips can only wear the outer surface of the rotor ring, avoiding the shaft being scratched. The double-lip PTFE lip seal is filled with special additive medium with low coefficient of friction and can offer excellent dry friction performance, which can provide excellent sealing protection with high velocity and good adapting to shaft run out .The outside of PTFE lip seal is the magnetic end seal. The magnetic face seal can adapt to huge shaft run out compared to lip seals, especially in the presence of particles, such as dust.