Plain Bearings (sliding friction)
DUNLOP Plain, rod end, spherical bearings and ball joints
For plain bearings, sliding friction occurs when two surfaces, generally separated by a third medium such as PTFE, bronze, nylon or lubricant, move relative to each other.
Specific pressure is determined by the strength of materials selected, this historical principle is used for all types of plain bearings in their various applications.
The main advantage of plain bearings lies in their design and structure, they are frequently used in maintenance-free designs and require less space in a machines design.
Rolling Bearings (rolling friction)
DUNLOP Deep groove, angular contact, self-aligning, thrust, cylindrical, taper, spherical and bearing units
Rolling bearings work with the principle of rolling friction, the applied load is transmitted by rolling elements, rotating around and between two bearing rings, normally guided by ring raceways grooves. Usually the rolling elements are positioned within the bearing by separators, also termed retainers or cages. As described for plain bearings, rolling bearings also require lubricant separation of the metallic parts.
This, along with a good surface finish, ensures smooth running surfaces and reduces friction from the transmitted forces, resulting in minimal power loss. The principle distinction between rolling element bearings and their initial bearing description is generally classified solely due to the rolling element shape (e.g.. ball or roller etc).
The differences between ball and roller bearings are also considered in the calculation formula for rolling bearings.
Please refer to the individual bearing sections for product information.