Mobil has put out a whitepaper following research conducted together with Schaeffler Technologies into the causes of white etching cracks (WEC) in the gearboxes of wind turbines.
WEC is blamed for 80% of gearbox failures in wind turbines, so the report will be of great interest to operators looking to avoid bearing failures that lead to critical equipment failure and expensive repairs.
One finding that will relieve many operators is that lubricants free from metal additives—like Mobil SHC Gear 320 WT, which is available through Mobil UK stockists—have been shown to not contribute to WEC. Instead, the report points to metal-containing additives as contributing to the problem. It particularly highlights magnesium, calcium, and sodium alkyl sulfonates, as well as zinc dialkyldithiophosphate, as potentially causing issues through increased below-surface stress and greater friction.
Schaeffler Technologies, a prominent bearing manufacturer, teamed up with ExxonMobil to conduct the project to investigate the effects of lubrication in WEC. While WEC can result from factors other than lubrication, the findings will enable windfarm operators to confidently select suitable lubricants like Mobil SHC Gear 320 WT.
Industrial Marketing Advisor Jarmo Vihersalo of ExxonMobil said:
“Working side by side with the team at Schaeffler Technologies, we are proud that our leading wind turbine gear oil—used in more than 40,000 wind turbines worldwide—is now proven not to contribute to WEC. While WEC remains an issue for the industry, we hope this news will at least alleviate some concern.”