Feature Article: Wind Turbines

With the increasing need to monitor long-life, high performance wind turbine gearbox lubricant, the RULER will bring you the answer, by measuring antioxidants on-site, all gearbox lubricants and greases used in the wind turbines, using antioxidants as amines, phenols, phenates, zincdithiophosphates, etc. used as single antioxidant or as synergistic mixtures.

By measuring the amount of remaining antioxidants (Remaining Useful Life), wind turbine operators will be able to detect early oxidative degradation before acidic compounds and oxidative compounds like varnish, and sludge will start to appear. These oxidative compounds are to be avoided as the accumulation of these in lubrication orifices, piping and coolers impairs circulation of oil and causes higher bearing and oil temperatures. Higher oil temperatures greatly accelerate the rate of oil oxidation.

Operator Benefits

This proactive maintenance strategy has proven for wind turbine operators to result in following benefits:

• Replace all off-site analysis with RULER analysis, by combining RULER with other on-site screening tools (saving sample preparation time, shipment costs and operator time)
• Measure and know at any time the lubricant life - contributing to lubricant life assessment and extension (saving costly downtime costs)
• On-site lubricant quality control (saving mechanical failure to mixing of type of lubricants)

Value of RULER:

1. To be part of on-site lubricant screening programs, which can be performed in complement with off-site (laboratory) programs.
2. Screening programs consist of testing water contamination, cleanliness (particle count), viscosity and oxidation (RULER).
3. Will reduce costly off-site analysis by replacing analysis like FTIR, PDSC, FTIR, and HPLC by RULER measurement for antioxidants.
4. By measuring and trending the lubricants' oxidative health condition, operators will detect abnormal oxidative signals, as part of root cause failure Analysis (RCA).
5. RULER can be used on a wide range of lubricants divided in 2 categories

   a. Gearbox and main bearing lubricants
   b. Greases (main gearbox and generator bearing)

The graphs below show you the typical graphs for these lubricants.

Gear box lubricant

Greases (main gearbox and generator)