Types of loads
The bearings are selected based on the type of dynamic and static load and speed, it is designed to take. Definitely, bearings can not be selected randomly. Each type of bearing is designed for certain type of function. A bearing selected wrongly, will not give desired performance and in most of the cases would fail prematurely.Let us look at the different types of loads, that act on any bearing. There are basically three types of loads acting on a bearing. They are :-
What is Preload?
Preload can be defined as the internal bearing load without applying any external work load. There can be axial & radial preloads.
Why Preloads?
There are many instances when preload is desirable. They are:
- The design requires stiffness, for vaious reasons like natural frequency.
- Low noise and vibration are the criteria.
- The shaft can not afford to be loose guided, e.g. shaft of a drilling machine.
- Comphensates wear & settings, e.g. Automotive differential where misalignment of gears is unacceptable
Methods of Bearing Preload:-
- Preload by using axial spring load.
- Use of an inactive baring and/or nut, e.g. Angular contact ball bearing in pairs.
- Customs built methods, which are designed to keep the separable bearings in proper contact.
Drawbacks of Preload:-
- Sytem requires higher torque and hence higher energy consumption.
- The bearing temperature may rise.
- The life may become shorter, if preload is not properly managed.