This type of needle roller bearing consists of a needle cage and a hardened, thin special-steel plate outer ring which is used as a raceway.
These bearings are produced in standard open type and closed end type. Open type has a wide range of possible applications. Closed type is completely closed on one side of the outer ring and is ideal for use when perfect closing of the shaft end is desired.
Both open and closed bearings are suitable for very tight and less demanding applications, especially where the hole in the housing cannot be used as a raceway.
HK types are supplied either without seals or with one (RS) or two (2RS) sealing rings. The sealed type has a wider outer ring than the standard type and is installed with seals consisting of a reinforcing ring and special synthetic rubber to prevent grease leaks and the entry of foreign particles.
BK needle sleeves are closed on one side, so they are suitable for mounting on shaft ends. They are not sealed on the open side.
Metric bearing series: HK, TA, TLA (open), BK, TAM, TLAM (closed), YT, YTL (full complement open type), HMK, with increased load capacity.
Inch bearing series: B, BH, M. MH, J, JP, JH, JTT, BA, BHA, BAM, BHAM, YB, DCL, HCK