Deutsche Windtechnik Develops Special Erosion Protection for Rotor Blades
In cooperation with the paint manufacturer, Colorvision, Hamburg, Deutsche Windtechnik has developed a special coating for rotor blades on wind turbines which meets the extreme requirements of erosion protection needed for rotor blades.
The abrasion resistance of the Leading Edge Protector (LEP) required has been tested and confirmed at the test laboratory of the Institute for Lacquers and Paints, ILF, Magdeburg by means of a high-pressure water-jet test; all test items completed the test run without any resultant surface defects. In the course of further test runs, the LEP proved to be the only product currently available on the market with outstanding properties for application in both onshore and offshore wind farms.
The paint system and the study results were presented at the fair “WindEnergy Hamburg 2014” last week.
“Our objective was to develop a new coating which would provide a wide scope of application, covering a broad temperature range and ensuring resistance to extreme air humidity. The system should also be simple to use and fault-tolerant,” explains Stefan Brassel, Manager of the Rotor Blade Service department, when describing the goals of the new development. “After executing a range of preliminary tests and gaining experience in field tests, we were very pleased to receive confirmation of the quality of the new coating from an approved test laboratory.”
Wide Scope of application
Initial application tests were conducted under real conditions on rotor blades in a wind farm in Germany (onshore) in 2012. After one year there was no sign of any abrasion or similar damage. These tests were followed by UV tests and adhesion tests in the lab without any negative findings. In May 2014, lab tests conducted in rel. humidity of over 90% confirmed that the leading edge coating LEP could be applied in a wide range of temperatures with a high level of air humidity. This means that the LEP can be used during production in the hall as well as on the suspended rotor blades in the wind farm in the course of maintenance and service work.
Repairing of rotor blades during servicing
The leading edges of the rotor blades in wind turbines are subjected to a high load, particularly in the final third towards the blade tip, as a result of the increasing rotational speed, and show clear signs of abrasion through to erosion damage the longer they are in operation. Even well-known protective paints and foils available on the market do not provide continuous protection over a period of 20 years which is why the repair of erosion damage in the course of servicing work is gaining importance. Fields of application with low temperatures and high air humidity are required.