Rotary Bearings & Housing Units
What are rotary bearings?
A rotary bearing is a component used in motion systems that allow rotation of moving parts. They have an inner and outer surface (races) with metal balls or rollers between them. This allows the surface to slide over a shaft when in motion, reducing friction as there is low surface area contact.
What is the different between a ball bearing and a roller bearing?
Rotary bearings are classified by the type of bearing that hold the loads in the cage between the races - ball or roller. Both types can support different primary load directions, known as radial loads or axial loads (thrust).
Ball bearings have round ball to separate the races, which creates a very small contact area, highly reducing friction and making them ideal for high-speed applications. They are categorised by the configuration of the outer race. Common types include deep groove and angular contact ball bearings.
Roller bearings have cylindrical rollers to separate the races which improves load distribution. They are available in different shapes and can handle high loads. They are categorised by the shape of the roller. Common types include tapered roller bearing and needle roller bearings.
What are rotary bearings used for?
Rotary bearing bearings are designed to be used in a wide range of machine motion systems to ensure continuous low friction movement. They can be usually found in:
- Electric motors
What do I need to consider when selecting a bearing?
Once the bearing type is known, there are many other varying specifications of rotary bearings for consideration that include:
- Primary load direction - radial or axial
- Mounting configuration
- Environment to be used in
What lubrication should be used with rotary bearings?
Bearing failure is mainly caused by lack of lubrication so it is important to select the proper oil or grease for the application.
- Grease lubricants adhere well and usually last longer due to the thick consistency. They are best used in moderate to high load applications.
- Oil lubricants dissipate heat well and have a lower viscosity, making them more suited to high-speed or low torque applications.