Bearing Designations

Bearing Designations

Metric bearings The designation of Bearings is as per the international standard, ISO 355-1977. Metric bearings identified by the prefix K-J follow the designation system described below for inch-size bearing. Inch sizes Inch-size taper roller bearings are designated following a system which is completely different from that used for metric taper roller bearings. The inner ring with roller and cage assembly, known as the cone, and the outer ring (cup) have individual designations. The complete bearing designation consists of the cone designation followed by the cup designation, the two designations being separated by an oblique stroke. The cones and cups belong to various “bearing series” Any cup belonging to a particular series can be assembled with any cone of the same series to form a complete bearing. The cone, cup and bearing series designation generally consist of a three to six-figure combination and may be preceded by a letter combination (LL, L, LM, M, HM, H and HH). The letters serve to indicate whether the bearing series is light or heavy.