Improving the Analysis of Gear-Oil Debris with a Compact Filter

Filter debris analysis (FDA) is a condition-based monitoring tool used by mechanized industries to identify wear mechanisms in critical, oil-lubricated machinery. Often discarded during regular maintenance, the filter acts as a trap with potentially valuable wear data that may not be collected or analyzed consistently using more standard, periodic oil analysis (oil analysis is good for trending oil deterioration). Using particles liberated from the filters, the laboratory can use several techniques, including a scanning electron microscope (SEM), to provide rapid, automated counting of large wear particles into size bins and classification by elemental composition. FDA is not currently a standard condition monitoring tool used in the wind industry. Utility-scale wind turbines have large gearbox oil filters, typically 15-30 inches (400-800 mm) in height, weighing 10-20 pounds (4-9 kg). Because of the large filter size, costs of logistics and analysis are barriers to regular use of FDA. Thus, researchers from the National Wind Technology Center at the National Renewable Energy Laboratory conducted a test program with Hydac Technology Corporation and SGS Herguth Laboratories, Inc. to overcome these barriers as part of the Drivetrain Reliability Collaborative (formerly known as the Gearbox Reliability Collaborative).