• Shaft diameters from 4 inch to 11.25 inch (101.6mm to 285.8mm)
• Turning reach of 16 inch (406.4mm) from the spindle face, or 22 inch (558.8mm) with the optional extension
• Pneumatic drive running on 6 bar (90 psi) at 0.85 m3/min (30 CFM)
• Operational weight of 90.7kg (200 lbs)
• Supplied with tooling, for hire on its own or with a BLJ technician

A portable journal turning lathe mounts on the end of the shaft and turns its cutting tool around the journal, instead of spinning the shaft in a conventional lathe. That is what lets a large shaft be machined without lifting it out of the plant.

1. Expose the shaft end. The gear or bearing is removed so the end of the shaft is accessible.
2. Mount. The lathe bolts directly to the end of the shaft.
3. Centre. Adjusting screws centre and align the lathe on the shaft axis, even if the end face of the shaft is no longer square.
4. Turn. The turning bar reaches along the journal and the tool feeds at 0.076mm to 0.279mm per revolution, bringing the journal back to a round, concentric surface.

Because the machine references the shaft itself, the journal is machined about the axis it actually runs on.

Download the journal turning lathe data sheet (PDF)

Four things decide whether the lathe can do the job on site. Checking them before mobilising is what stops a wasted trip.

• Swing clearance: at least 212.7mm (8.37 inch) radius around the shaft centreline, so the machine can rotate.
• Length off the shaft end: around 787.4mm (31 inch) of clear space for the machine with the turning bar fully retracted.
• Reach to the journal: the worn journal needs to sit within 406.4mm (16 inch) of the mounting face, or 558.8mm (22 inch) with the optional extension.
• Compressed air: a supply of 6 bar (90 psi) delivering 0.85 m3/min (30 CFM).

Send us the shaft diameter, the journal position and a photo of the access around the shaft end, and we will confirm the fit before hire.

Shaft journals are the load-bearing surfaces that carry bearings, pulleys and couplings. When they wear, the result is vibration, poor fitment and faster wear on everything connected to them. A journal turning lathe is used for:

• Restoring bearing journals damaged by a failed or worn bearing
• Re-turning journals worn by damaged pulleys
• Bringing a journal back within tolerance for concentricity and roundness
• Re-turning large shafts and roll journals that are too big or too costly to remove
• Avoiding a shaft replacement where the journal can be machined back to specification

It is common on crushing and screening equipment, pumps and rotating process equipment, and marine vessels. BLJ’s recent work includes restoring both 175mm journals on a mobile crusher shaft for a Brisbane client, and journal turning on a dredging vessel for a dredging company in South Queensland.

Whether machining is cheaper than a new shaft depends on wear depth, lead time and downtime, and the trade-off between repair and replacement is usually decided on those three. Where a keyway on the same shaft has also worn, it can be recut with our portable keyway milling machines in the same visit.

You can hire the journal turning lathe from BLJ In-situ Solutions and run it with your own people, or we can supply it with a BLJ technician who carries out the work as part of our journal turning services.

What is included with a hire: the lathe and the tooling and equipment required to set it up and operate it.

What you need to provide: compressed air at 6 bar and 30 CFM, access to the shaft end with the gear or bearing removed, the clearances listed above, and confirmation that the equipment is isolated and safe to work on.

Journal turning is one part of BLJ’s wider on-site machining and mechanical maintenance work. Brisbane operators can build onsite journal turning into their planned maintenance programs, and unplanned shaft failures are handled through our emergency and unplanned onsite machining services.

We support sites across Australia from our workshops in Brisbane and Gladstone.

BLJ In-situ Solutions is certified and registered by TQCS International Pty Ltd to ISO 9001:2015 Quality Management Systems standard. All work undertaken by our technicians is executed in accordance with its Quality Management System processes.