Turbines have to withstand a lot of stress from long operating hours, guarding off wind, heat and rain, so it is important that operators do all they can to ensure that they are running at their optimum capability. One of the factors that can impact the health of a wind turbine is choosing the best turbine oil for the job.
The right turbine oil, if it has been correctly tested and maintained, will last longer, and help the turbine to operate more effectively than a poorly chosen, tested and maintained one. This is why it makes sense to make the right lubricant choice from the beginning of your turbine’s life.
The right oil for the job
In order to select the correct turbine oil for your machinery, it is important that you have an understanding of the characteristics, both physical and chemicals, of turbine oils, which are not the same as other lubricants you may have used in the past.
Lubricating oils used for the operation of turbines are known as Rust and Oxidation inhibited oils. These oils are used for turbines whether they operate on steam, water or gas. It is important that you use an R&O inhibited oil because turbines have a number of unique challenges, including operating cycles, geometry, and operating temperature, which can put them at risk of contamination.
A steam turbine that is looked after correctly should last two or three decades. The main cause of early steam turbine failure is oxidation, most commonly due to contamination by water, which can cause rust to form and set off the process of oxidation.
Due to their very nature, steam turbines are regularly exposed to water, which means that it is important to choose an oil that has additives, including rust inhibitors, antioxidants and demulsibility improvers, as these can counteract the worst effects of water contamination.
The issue that caused most gas turbine oils to fail early is the extremely high operating temperatures they reach. Gas turbines can heat up to as much as 121°C, which means that they require an oil that is formulated specifically for higher temperature applications, such as Mobil DTE 832.
The best oils for hydro turbines are ISO 46 and R&O oils. It is important to choose an oil with demulsibility and hydrolytic properties, as the constant exposure to warmer and significant changes in operating temperature can alter the stability of oil if these specifics are not present.