Recently, a client of ours in the pulp and paper industry had a Radicon BU400 underdriven worm gearbox fail on them. The Radicon unit was on an important piece of machinery, and the failure proved to be quite costly in terms of production lost. We were given the task of making sure that a failure such as this would not happen again.
Diagnosis
On a very tight schedule, we inspected the Radicon unit with a view to an urgent repair. Existing machine hardware required that this unit be returned to service, as size and design restrictions meant that no replacement would be suitable. Immediately upon inspection, we found that the wormwheel had failed. This in turn necessitated new bearings and seals, which are a standard part of a repair anyway.
The original failure had been caused by the lubricant being separated from the wormwheel and wormshaft, increasing heat (and wear) from metal to metal contact. Eventually, the heat build-up caused heavy pitting on the teeth of the wormwheel, necessitating replacement.
What Next?
Lead times for replacement spare parts for this equipment are always very long (over three months), as all stock is made to order in the UK. Obviously, this would not do on this occasion, so we took matters into our own hands.
Radicon Repair – Stop Future Failures
In addition to commissioning the manufacture of a new wormwheel, we designed and fabricated an application-specific oil deflector, to ensure that lubricant remains where it should during operation.
The deflector was fabricated from a single piece of aluminium plate to ensure that it remained robust during operation and mounted with socket head cap screws.
Outcome
Since being returned to service, the repaired BU400 hasn’t missed a step. Lubrication control is at the heart of the turnaround.
