First, some background on bushings in general. Bushings, also known as “Plain Bearings” or “Sleeve Bearings,” are designed for use in numerous applications and offer features and benefits unavailable with many rolling-element bearings. Bushings are distinguished from rolling-element bearings primarily by the fact that they consist of only one part, which may be built up of different materials, layered and combined into a load carrying system.
Depending on the application, bushings are available for operation with supplemental lubrication or to run “dry”, with no additional lubrication. Bushings are available impregnated with lubricant, with lubricant “plug” inserts, or with inherently low coefficients of friction. Bushing materials include cast or machined metals, stabilized polymers (“plastics”), fiber-wound composites, and combinations of different types of materials. Selecting the right bushing for each project requires detailed knowledge of the application requirements and experience with bushing technology. AST’s bearing experts are available to help with advice and guidance to make the selection process as easy as possible.
Now, onto our specific category: bronze wrapped bushings. Bronze wrapped bushings are wrapped from a cold formed homogenous bronze (CuSn8) with exceptional material properties. Depending on the lubrication conditions, the bearing can be provided with diamond shaped lubricant indents (for grease) or through holes (for grease or oil). With this design, a lubricant film rapidly builds up during the initial run-in period of the mating parts and thereafter running friction is considerably reduced.
The AST090G material has graphite embedded into the diamond indentations to provide good lubrication conditions on start-up, even when operated with no added lubrication. This bearing design provides high load carrying capacity, good fatigue properties, dimensional stability, and improved thermal conductivity. Tighter tolerance control can be achieved by re-machining the assembled bearing.
For more information on bronze wrapped bushings, including details on AST’s full product line, whitepapers and 3D CAD models, click here. If you have a specific question regarding these or any bearings, contact AST’s team of tribological experts by clicking here.