Turbine Oil Quality and Field Application Requirements

Abstract

Power generation and other types of industrial turbines have always required the use of high quality lubricants. This paper will discuss the evolution of turbine oil formulation technology, and the use of different quality products in different applications. The original “R&O” type circulating oils, which are suitable for use in many hydraulic and steam turbine systems, have a long and successful history. Next came high performance products, designed for increased operating life. Finally, products have been introduced recently that provide the high stability needed for systems which operate under severe conditions of thermal stress, such as may occur in certain gas turbine operations. Selecting a suitable turbine oil requires meeting the application requirements of equipment and service environment, while balancing initial and life cycle cost considerations and oil performance history. Field experience with different types of equipment and different turbine oil types will be described, with examples of situations where each oil type has performed successfully. Experience with field performance problem-solving will also be addressed, such as a gas turbine filter plugging problem which was resolved by selecting the appropriate turbine lubricant. Turbine equipment manufacturers generally specify the properties and performance requirements of turbine oils according to the type and severity of operation. Standardized laboratory tests provide an indicator of an oil's performance, although such performance needs to be confirmed by field experience. New testing tools are needed which will better correlate to the performance requirements of new generation equipment.