Bearing speed limit index

The bearing type table usually has a speed limit indicator, so what does it specifically refer to?

The speed limit of the bearing is an estimated speed: the number of revolutions per minute below which the bearing will remain in normal use. Limit speed given in bearing size table. The data, which are usually based on the installation on the horizontal shaft, are calculated by testing under the premise of good lubrication operation and suitable load.

During the working process, if the bearing runs beyond a certain speed, it will begin to produce uncontrollable internal heat. For example, precision bearings applied to the machine tool industry, under the action of periodic load in the working environment, the contact surface is prone to exhaustion and damage, which is one of the common reasons for bearing failure. Therefore, to ensure the service life of the bearing, its manufacturing material must have a high contact fatigue strength.

At the same time, the speed limit will also be affected by the bearing structure type, size, lubrication form, and special design. Changes in the type of bearing seal will also affect the speed limit of the bearing.

In addition, if the bearing is mainly used to bear the radial and axial combined load based on the radial load, it is generally not appropriate to bear the axial load alone, the inner ring and the outer ring can be installed respectively, and the shaft is not allowed to tilt to the shell, and additional axial force will be generated under the radial load. The size of the axial clearance of the bearing has a great relationship with whether the bearing can work normally. When the axial clearance is too small, the temperature rise is higher. When the axial clearance is large, the bearing is easy to damage. Therefore, special attention should be paid to adjusting the axial clearance of the bearing during installation and operation, and pre-interference installation can be performed if necessary to increase the rigidity of the bearing.