Case Studies: Gear Boxes

Tyre manufacturing plant upgrade

Recently the engineering manager of a major multinational tyre manufacture sought the help of Visiscope; the purpose being to ascertain the condition of the worm wheel reduction gear boxes of the imported second hand bag-o-matic tyre presses.

These presses were part of a production upgrade of the factory, however the design and location of the reduction boxes in the presses meant that a costly and time delaying strip down exercise might be required.

After completing a contractors safety training session, the Visiscope technicians then set about to undertake NDT inspection of the two reduction box's. Although the location and design of the reduction box's hampered direct viewing access, the technicians using a 5 meter long video scope were able to view the gear wheel via the oil fill and drain points.

As a result of this NDT inspection, the factory engineers were able to make the decision to continue with the installation of the presses. The video recorded images of the gear wheels will be retained by the maintenance engineers for comparison assessment at a later date.

Tyre Plant Press Gear Box inspection
(Note the Gear Wear in right Image)

Commercial Fishing Boat

A Wellington based commercial fishing boat was conducting a routine maintenance service on there main winch gearbox. After the gearbox was drained of oil it was discovered that at the base of the gearbox existed loose circular metal components. It was thought that a bearing had collapsed.

To gain access to all of the bearings around the winch drum a major strip down would be required. It was estimated this would put the fishing boat out of service for a 3 week period. The Captain did not want to run the risk of going to sea and losing a net due to a potential gearbox failure.

Visiscope technicians where called to site to conduct a RVI. The 1.5m long video fibrescope was used to scan each bearing. The winch was slowly rotated enabling the Visiscope technicians to thoroughly scan each bearing. It was discovered that all bearings were in good condition.

It was concluded that a failure of some kind had occurred some years ago and the sump of the gear box had not been cleaned out. It took the Visiscope technicians approximately 4 hours to carryout the inspection. The Visiscope RVI gave the Engineering team peace of mind by enabling them to carryout an accurate condition assessment.

After the physical inspection was carried out the video footage was replayed a couple of times by the Engineering team to check that nothing was missed in the initial survey. Should a potential failure like this have occurred at sea tens of thousands of dollars would have been lost in revenue.

Gearbox Bearing Inspection