News Details

I visited a site last week to discuss the problems on a gearbox which included short bearing life (approximately 2 years) and short oil life (less than 3 months on the 100L sump).

 

Much of the challenge is the wet environment. Despite the desiccating breathers, there is a severe moisture level in the oil, and the added complication has been the short desiccating breather life of less than a week.

 

The oil looked muddy! This was due to the free water in the sample along with the high rust particulate levels from the system.

 

So what to do? For many, this may simply be a case of living with the problem and scheduling more downtime to cope with the gearbox repairs and oil changes. While some maintenance managers might have attempted to address the problems, they probably would have met resistance from management not to spend any more on their restricted budgets.

 

But for this particular maintenance manager, the reason I was there, this was just another of the many challenges he faces in his goal for world class standards. Despite the failure of the desiccating breathers at this stage, he knows that he can solve this issue and enjoy the benefits of life extension on the oil and gearbox, reduced downtimes, and costs, and improved compliance in his safety and quality standards. He is willing to try, whether it be filtration carts, or alternative breather arrangements or even a new oil type. And he is willing to learn from the oil analysis data to seek all areas of improvement.

 

It occurred to me whilst driving home that despite the challenges, this site will indeed succeed with this attitude.

 

We look forward to your feedback.

 

Regards,

Martin Williamson at KEW Engineering Ltd.

 

 

Upgrade breathers to ensure good air quality free of particulate and moisture - use a desiccating breather and if necessary mount the breather away from the gearbox to avoid premature failure in a wet environment.

 

Consider, if necessary, a bladder type expansion chamber to eliminate air flow into and out of the gearbox, yet still allowing air expansion and avoiding seal damage.

 

Upgrade the drain and breather pipes to have a tee-piece for fitting a filter cart. Regular filtration of the gearbox with a filter cart will ensure clean oil and in some cases will also assist with removal of accumulated moisture.

 

If necessary upgrade to a higher quality oil to overcome temperature and moisture issues, but do not assume the oil will rectify the root cause issue, it will only mask it.

On large volume systems, add permanent off-line filtration along with oil sampling connectors and tee-piece connections for more efficient drains and re-fills or top-ups. If necessary, add a cooling circuit to reduce overall oil temperature and extend the oil life.

Shield any exposed seals especially in plants where high pressure washdown sprays are used.

 

Fit a best-practice connector for oil sampling to ensure accurate and consistent analysis and trending of the results.

 

Work with the gearbox OEM to ensure proper flushing and achieved cleanliness during build and assembly.

 

Store gearboxes correctly in the stores to avoid contamination and degradation thorugh rusting and corrosion.

 

Ensure alignment, balance and mounting of the units are correct.