21317JV Nilos Ring for 21317 Series Bearings 100x180x4mm

Nilos JV Sealing Rings: A Nilos ring that seals the inner roller bearing ring is described as a JV type. They are used to provide sealing for bearings that have no shields or seals. A Nilos ring of suitable dimensions can be installed so that the Nilos ring fully encloses the open area of the bearing.
Nilos rings are required in particular installations where excess dirt or debris may be present that could penetrate up to the bearing, if some further mechanical protection is required or if condensation is formed.
Sealing is produced by placing the sealing edge of the Nilos ring under light pressure at the inner bearing ring so that it rubs to a greater or lesser depth into the hardened roller bearing ring. The fine labyrinth produced as a result prevents the leakage of grease and the penetration of dirt into the bearing. If sealing is required around the outer raceway then an AV type Nilos ring should be used.