The rotational speed of a bearing is normally affected by friction heat generated in the bearing. If the heat exceeds a certain amount, seizure or other failures occur, thus causing rotation to be discontinued.
The limiting speed is the highest speed at which a bearing can continuously operate without generating such critical heat.
The limiting speed differs depending on various factors including bearing type, dimensions and their accuracy, lubrication, lubricant type and amount, shapes of cages and materials and load conditions, etc.
The limiting speed determined under grease lubrication and oil lubrication (oil bath) for each bearing type are listed in the bearing specification table.
These speeds are applied when bearings of standard design are rotated under normal load conditions (approximately,C/P≧16*，Fa/Fr≦0.25
Each lubricant has superior performance in use, according to type.
Some are not suitable for high speed ; when bearing rotational speed exceeds 80 % of catalog specification, consult with JTEKT.