A bronze eccentric bush in a cone crusher is a wear part by design: it conforms, embeds tramp metal and sacrifices itself before the shaft does. Mining & Aggregate duty is shock, abrasion and water sprays with little maintenance access; the material is what decides whether the bearing survives it.
| Industry duty | shock load from crusher jaws and falling ore, in continuous abrasive dust |
|---|---|
| Typical media | ore dust, slurry, water spray |
| Housing temperature | −20 to +120 °C |
| Material and grade | cast bronze (CuSn6 / C93200) |
| Hardness | 60–80 HB |
| Temperature ceiling | 250 °C |
| Corrosion / chemical | water and seawater; needs grease or graphite plugs |
| Relative cost | ≈1.5× of a standard 52100 bearing |
A cone crusher's eccentric runs at 200–400 rpm under a load that reverses every revolution, in a housing that is deliberately allowed to move. A rolling bearing could not survive the misalignment or the contamination, so the design uses a bronze bush that conforms, wears predictably and can be replaced in a planned shutdown rather than an unplanned one.
| Position | Bearing type | Material / finish | Why it works there |
|---|---|---|---|
| Cone crusher eccentric | CuSn6 bush | Bronze bush, oil lubricated | Conforms under eccentric load; a replaceable wear part. |
| Pitman toggle seat | Bronze seat | Bronze seat or wear plate | Takes the shock and wears instead of the frame. |
| Screen shaft bush | Bronze bush | Bronze bush, grease | Slow rotation with grit; bronze tolerates it. |
| Material | Fit here | Choose it when |
|---|---|---|
| Bronze | Best fit | Eccentric and toggle positions where wear is designed in. |
| 100Cr6 / 52100 | Workable alternative | Where speed is high enough for rolling contact and the structure is stiff. |
| POM | Workable alternative | Light, clean positions only — never in a crusher. |
Typically one to three years depending on the duty and the oil system. It is a planned replacement, not a failure.
The bush seizes to the shaft within seconds, and the shaft is destroyed with it. That is why the oil pressure interlock exists.
Sometimes, if the wall thickness allows and the eccentricity is preserved. Most plants replace it.
Hardness, temperature, corrosion and equivalents for cast bronze.
Read →Typical duty, recommended types and suffixes for mining & aggregate.
Read →Crushers & screens — crusher, screen and conveyor pulley positions in hard-rock plant.
Read →Wash plant & slurry — wash plant, dewatering and slurry pump positions where water is constant.
Read →Send the position, bore size, quantity and the medium it sees. We reply with the material certificate, clearance class, lubricant and price within 30 minutes on working days.