Investigating the effect of temperature and time on the starvation of lubricants for the wind turbine industry

ABSTRACT In the wind turbine industry, mechanical components sometimes have to operate under starved lubrication. This occurs mainly after maintenance and/or repairing procedures, when the wind turbine is starting up again after a prolonged inactive period. In field observations have shown that oil starvation is more prominent in warmer climates and of course for longer durations where the mechanical components remained ‘inactive’. To get a better insight on this issue, a validation test procedure was developed based on reciprocating sliding tests. This protocol was used to investigate the starvation behaviour of two commercially available oils on metallic components, which were exposed at different temperatures (ranging from −20° to 40°C) and durations (ranging from 5 to 21 days). Based on these tests the resistance to starvation (failure time) and the effect of critical waiting time and temperature to initiate starvation were assessed.