Bearing Test Bench Now Fully Functional
Over the past months, the first blade bearings have been tested in Hamburg on the new BEAT 6.1 test bench using a highly simplified yet customary setup. The installation of specially manufactured hybrid components means that, with immediate effect, dynamic loads can also be applied to the bearing, which, in turn, produces particularly realistic test conditions. The latest, now fully operational test bench to join the IWES portfolio is to be presented to guests right in time for the site opening on May 6.
The improved insight into damage and damage progression on wind turbine bearings subject to very high loads can now be integrated directly into the design stage which, to date, was essentially based on experience. Optimized blade bearings help to prevent turbine downtimes and make turbine operation even more economic.
Bearings are among the components to be exposed to the greatest loads and have a comparatively high failure rate. They are a factor preventing further turbine growth. The first test runs for bearings in continuous operation have already been conducted and will be followed by others up until mid-August. For the endurance tests for bearings for wind turbines up to 10 MW, the test engineers at Fraunhofer IWES use complex data analyses to create time series which simulate various damage mechanisms. This makes it possible to test the resilience of bearings over their entire service life within just a few months prior to their installation in a wind turbine. The goal of the BEAT 6.1 test bench (Bearing Endurance and Acceptance Test rig) is to simulate the loads which act on the 10-ton bearings during operation as realistically as possible.
The expansion of the test bench to include hybrid components was thus the last decisive development stage. Where wind turbines feature more rigid connection constructions (e.g., on the braces of the rotor blade), the components also apply loads to the blade, whereas where the design is more flexible, e.g., on the trailing edge of the rotor blade, the components are also more elastic. Dynamic loads are modeled in this way, and a realistic test situation is created.
“The new test bench at the site in Hamburg bundles activities and also facilitates the experimental testing of bearings for the next generation of wind turbines. With the BEAT 6.1. test bench, Fraunhofer IWES has further enhanced its portfolio of validation services, which help turbine and component manufacturers to verify further and new developments prior to their market launch”, stressed Andreas Reuter, Managing Director of Fraunhofer IWES.
Rotor blade bearings measuring 5 meters in diameter from the HAPT (Highly Accelerated Pitch Bearing Test) research project have been tested on the new test bench right from the very start. The test series with function and fatigue tests will continue to run up to summer 2021. This will allow blade bearings to be validated at a very high level.
The goal is to develop methods for the accelerated testing of blade bearings in cooperation with the research partners, the bearing manufacturer IMO, and the Institute of Machine Elements, Engineering Design, and Tribology (IMKT) at Leibniz University Hanover.
“The possibility of testing IMO bearings on this unique bench gives us a real knowledge edge. When designing new and ever larger bearings in the future, we will be able to refer to comparisons between various bearing concepts”, explained Dr. Henrik Albertsen, Head of Application Technology at IMO.
Following the test runs in the public project, the infrastructure will be made open for use by all interested parties.