Info Centre >> Fuel and Lube Oil Technical Manual >> 7. Lube Oil - Test Results >> 7.7 Turbine Oil
Turbine Oil
The table below shows the test parameters for Turbine Oils, including Steam Turbines and Gas Turbines .
Test equipment for Hydraulic Oil and Turbine Oil
| Turbine Oil | |||||||||||||||||||
Test Parameter |
Oil Condition |
Default Limit |
Comment |
||||||||||||||||
Viscosity (cSt at 40°C) |
Exceeds limit | < +/- 10% nom | Viscosity increase is more common than decrease. It should be noted and checked at more frequent intervals. Check that the correct grade of oil is used for top-up. | ||||||||||||||||
Water (%) |
Satisfactory | 0.05% - 0.15% | Upper limit should be checked against manufacturers’ data. Some oils, especially synthetic oils, cannot tolerate water - BEWARE. Water contamination may lead to hydrolysis of synthetic oils and rapid TAN increase. | ||||||||||||||||
f |
Borderline | 0.15% - 0.2% | |||||||||||||||||
f |
Exceeds limit | 0.20% > 0.1% | |||||||||||||||||
f |
—- synthetic oils | ||||||||||||||||||
TAN |
Exceeds limit | Change +/- 0.4 from nominal | TAN should always be monitored by trend as the TAN of some oils can fall from new then rise again as the oil ages. | ||||||||||||||||