The deep groove ball bearings manufactured by RKB are also available in closed designs, with seals or shields. The seals, which are normally made of acrylonitrile-butadiene rubber (NRB) with a metallic reinforcement, are retained in their correct position by a recess in the outer ring. The working temperature range is from -40 to 100 °C, with a peak of 120 °C for short periods of time.
Type ZZ
One-piece inner and outer ring
High strength two-piece pressed steel cage guided on balls (J)
Two non-contacting steel shields at both sides (ZZ)
Supplied already filled with grease for maintenance free operations
Shielded type to keep the grease inside the bearing without compromising the limiting speed
Type 2RS
One-piece inner and outer ring
High strength two-piece pressed steel cage guided on balls (J)
Two contacting rubber seals at both sides (2RS, or 2RSL for light contact)
Supplied already filled with grease for maintenance free operations
Sealed type to keep the grease inside the bearing and enhance contaminant exclusion