SKF supplies some sizes of single row angular contact ball bearings in the 72 B(E) and 73 B(E) series sealed on both sides. For information about the suitability of seals under various conditions, refer to Sealing solutions.
Bearings sealed on both sides are lubricated for the life of the bearing and should not be washed or relubricated. The bearings are considered virtually maintenance-free. If they are to be hot mounted, an induction heater should be used. SKF does not recommend heating capped bearings above 80 °C (175 °F). However, if higher temperatures are necessary make sure that the temperature does not exceed the permissible temperature of either the seal or grease, whichever is lowest. During start-up, grease may leak at the inner ring. For bearing arrangements where this would be detrimental, special design steps must be undertaken. For additional information, contact the SKF application engineering service.
Non-contact sealsBearings with non-contact seals can be operated at the same speeds as open bearings. The seals form an extremely narrow gap with the inner ring shoulder (fig. 1). They are made of oil and wear-resistant NBR that is reinforced by a sheet steel insert. The seals, which are fitted in a recess on the outer ring, make good, positive contact with the recess.
SKF single row angular contact ball bearings with a non-contact seal on both sides are identified by the designation suffix 2RZ.
Greases for sealed bearingsSealed single row angular contact ball bearings are filled as standard with the high performance polyurea grease (GXN). Its specifications are listed in table 1. The standard grease is not identified in the bearing designation (no designation suffix).
For non-standard greases, contact the SKF application engineering service.