Bronze Bushes

Bronze Bushes

Bronze bushes are plain bearings that support rotating or sliding shafts in a wide range of low-to-medium speed applications. They operate without rolling elements, relying instead on a film of lubricant — or in the case of self-lubricating types, the material's own internal lubrication — to carry the load between shaft and bush. Bronze bushes are a practical, cost-effective bearing solution for applications where ball or roller bearings are over-specified or impractical. AIMS Industrial supplies bronze bushes for maintenance and engineering applications across Australia.

Types of Bronze Bushes

• Cast bronze (SAE 660 / C93200): The standard engineering bronze bush. Good load capacity, excellent machinability, and widely available. Suitable for general industrial use — pivot pins, linkage bearings, conveyor rollers, and machinery pivot points. Requires external lubrication for best service life.
• Sintered bronze (oilite / SAE 841): Manufactured by powder metallurgy — the porous structure is impregnated with oil during production. This oil migrates to the bearing surface under load and heat, providing continuous self-lubrication. Ideal for applications where periodic regreasing is difficult or impractical.
• Wrapped bronze bushes: Formed from strip rather than cast — a thin bronze strip is rolled into a cylindrical bush shape. Lower cost, good for moderate loads. Often used in automotive and agricultural machinery linkages.
• Flanged bronze bushes: A flange at one end locates the bush axially in the housing as well as providing radial support. Used where thrust load or axial location must also be managed by the bush.

Load and Speed Considerations

Bronze bushes are best suited to low-to-moderate shaft speeds and steady loads. The key selection parameters are the PV value (pressure × velocity) — the product of the specific bearing pressure and the surface velocity. Each bronze grade has a maximum PV rating; exceeding it leads to rapid wear or thermal failure. For high-speed applications, rolling element bearings are more appropriate. For very slow movement or oscillation, bronze bushes are often the better choice.

Lubrication

Non-self-lubricating bronze bushes (cast and wrought types) require grease or oil lubrication, typically supplied through a grease nipple drilled into the housing. Lubrication intervals depend on load, speed, and operating temperature. In contaminated environments, more frequent lubrication is needed to flush contaminants from the bearing clearance. Oilite sintered bushes require no maintenance lubrication, making them suitable for sealed or inaccessible housings.

Sizing and Fit

Bronze bushes are dimensionally defined by bore diameter, outside diameter, and length. A controlled press fit into the housing is standard — the bush OD is slightly larger than the housing bore, and the bush is pressed in cold. After pressing, the bore should be checked against the required shaft clearance, as pressing can slightly reduce bore diameter.

Order Bronze Bushes from AIMS Industrial

AIMS stocks bronze bushes in standard sizes across cast, oilite, and flanged configurations. For non-standard sizes or large quantities, contact our team.