Cone crusher bronze bushings and sleeves: wear limits, measurement and RFQ guide

Why bronze bushings matter

In a bushing-type cone crusher, the eccentric bushing converts the rotation of the countershaft into the gyratory movement of the main shaft. The socket liner supports the head assembly and transmits crushing forces to the main frame. Frame bushings, countershaft bushings and main shaft sleeves provide radial support at other load points.

These parts rely on a pressure-fed oil film. When the film fails, metal contacts metal and a bushing can burn out in hours. For purchasers, the practical question is simple: what signs show that a bushing is near the end of its life, and what information does the supplier need to make an accurate replacement?

Parts to define in the RFQ

• Inner and outer eccentric bushings (eccentric sleeve)
• Socket liner (bowl-shaped bearing for the head ball)
• Frame bushing and spider bushing (upper main shaft support)
• Countershaft bushing and countershaft box parts
• Main shaft sleeve and head bushing
• Oil grooves, oil ports, dowels and any fasteners included in the assembly

Wear signals to record

Metso describes three typical signs of eccentric bushing burnout: total lockup of the crusher, overheating of the lubricating oil, and bronze filings in the screen of the hydraulic unit. A persistently low countershaft box oil pressure can also indicate excessive bearing clearance caused by bushing wear.

Common causes include improper lubricating oil, a lube system or oil pump failure, incorrect liner configuration, a closed side setting that is too small, off-center or segregated feed, excess fines in the feed, and incorrect crusher rotation.

When to inspect

The most practical rule is to inspect all crusher bushings at every liner change. Metso recommends this step to avoid unexpected stoppages. For Sandvik CH series machines, the spider bushing clearance is typically checked with a feeler gauge every 250 operating hours and at every liner change. Always use the manual for the specific machine to confirm limits.

How to measure

• Measure the main shaft outer diameter and the eccentric bore inner diameter at a minimum of four heights and two positions 90 degrees apart, then compare with OEM tolerances.
• After a burnout, clean and polish the main shaft and the inner diameter of the eccentric before installing a new bushing.
• Check bushing clearances with a feeler gauge at the positions specified in the manual.
• For the socket liner, use the spherical oil groove depth as the replacement guide; a common limit is replacement when the groove depth has worn to about 2.5 mm (0.098 in).
• Always inspect the head ball when replacing a socket liner. A scored or out-of-round head ball will quickly destroy a new liner.

Bronze alloy selection

Cone crusher bushings are usually made from leaded tin bronze, where the lead provides emergency protection if the oil film is briefly interrupted. A common general-purpose grade is C93200 (SAE 660), with a typical composition of about 81–85% copper, 6.25–7.5% tin, 6–8% lead and 2–4% zinc. Heavy-duty eccentric bushings for HP style machines often use a higher-lead tin bronze such as C93800, while Symons style machines commonly use C93700.

The safest specification is the one on the OEM drawing or reference number. Do not order by the word "bushing" alone; confirm the alloy, hardness, bore size, outer diameter, length and oil groove layout with the supplier.

RFQ information buyers should send

• Crusher model and machine series (for example HP300, CH440, GP200), plus the serial plate photo if available
• Part name or OEM reference number, such as eccentric bushing, socket liner, countershaft bushing or frame bushing
• Drawing, sample or used-part photos showing the worn contact faces and oil grooves
• Bore inner diameter, outer diameter, length and any keyway or dowel details
• Material request or original alloy information
• Quantity, destination country or port, packing requirement and required delivery date
• Operating evidence if a failure occurred: oil temperature, oil pressure, debris on the return screen, feed conditions and downtime history

Break-in after installation

After a new eccentric bushing is installed, Metso recommends a staged break-in: run the crusher free of load for 1 hour, then run for 2 hours at about 50% of the motor's nominal power, then close the crusher until about 75% power is reached and run for another 4 hours, then reach full load for 1 hour. Inspect the crusher between stages and watch for abnormal oil temperature or knocking of the adjustment ring.

Source notes

• Metso: Avoid burnout of your HP crusher's eccentric bushing explains burnout signals, causes, measurement after failure and the break-in procedure.
• Metso: Five steps to optimize crusher lubrication covers oil temperature, pressure, return screen checks and oil analysis.
• Metso crusher inspections describes daily, 1000-hour, wear-replacement and annual inspection scope.
• Qiming Casting: Cone crusher socket assembly documents socket liner replacement limits and head ball inspection.
• Bunting Bearings: C93200 (SAE 660) bronze data lists the typical composition and properties of general-purpose bearing bronze.
• Pilot Crushtec: Checking the spider bushing on Sandvik cones shows the feeler gauge check interval for CH420/CH430/CH440 machines.

FAQ

How often should eccentric bushings be replaced?

There is no fixed interval. It depends on lubrication quality, feed conditions and operating hours. Falling oil pressure, rising oil temperature or bronze debris on the return screen are reasons to inspect, and every liner change is a practical checkpoint.

When must a socket liner be replaced?

A common limit is when the spherical oil groove depth has worn to about 2.5 mm (0.098 in). Also inspect the head ball, because a damaged head ball will quickly destroy a new socket liner.

Can a quote be started from the model only?

Yes, but an accurate quote needs the part name or reference number, drawing or used-part photos, and bore, outer diameter and length measurements. Different batches and modifications can change the dimensions.

Can a new bushing be installed after a burnout?

Only after the main shaft and eccentric bore are cleaned, polished and measured. If they are outside tolerance, installing a new bushing alone will lead to a fast repeat failure.

RFQ support from XCT Mining

XCT Mining supplies independent aftermarket replacement bronze bushings and sleeves for cone crushers, including eccentric bushings, socket liners, frame bushings, countershaft bushings, main shaft sleeves and custom parts by drawing, sample or used-part photo.

Send crusher model, part name or reference number, drawing or photos, bore and outer diameter measurements, material, quantity, destination port and required delivery date to leon@xctmining.com or WhatsApp +86 13013110975.

XCT Mining is an independent aftermarket supplier of replacement crusher parts. Metso, Nordberg, Sandvik, Barmac, Terex, Symons and other names are used only to identify machine compatibility or replacement applications. All trademarks belong to their respective owners. XCT Mining does not claim to be an OEM, authorized dealer, official distributor or affiliated company of these brands.