An RBC-D 50 yoke from German special and custom machine manufacturer Ematec was used to install rotor blades on two EP-5 generation wind turbines, from wind turbine manufacturer Enercon, at a wind farm in the Königshain-Wiederau part of Germany. The wind farm is being built by energy company Leipziger Stadtwerke and wind turbine builder Eab New Energy.
The yoke automatically adapts to each specific rotor blade, balancing itself by identifying the centre of gravity for safe blade handling. Two counterweights at each wing of the yoke automatically adjust to the centre of gravity with or without the blade.
The yoke can handle blades ranging from 45 to 110 meters in length and stabilise them at inclination angles of up to ±30 degrees, ensuring uncontrolled movements are avoided.
The yoke was used in combination with the Autonomous Positioning System (APS) from Seasight Solutions facilitating installation without the use of taglines.
“The RBC-D has become indispensable in our installation process,” says Matthias Jöde, project manager at Enercon. “It offers complete process reliability and significantly accelerates the installation process.
“Our rotor blades can be flexibly mounted at various angles using Ematec’s yokes. With numerous sensors on the yoke we always have complete control and can correct any deviations immediately in real-time. If predefined thresholds are exceeded, the system stops automatically.”
Ematec says the system helps speed up installation as it can be used in wind speeds up to 10 m/s compared to traditional methods that only allow installation with wind speeds up to 8 m/s. “On average the APS saves us 2.3 days per construction site, days that would otherwise be lost due to weather conditions,” explains Klaas Schumann from Enercon’s site engineering department.
At Königshain-Wiederau each set of rotor blades was installed in just one-and-a-half days. Enercon has ordered 30 RBC-D yokes from Ematec in recent years and is deploying them worldwide.
The system is now being used at another windfarm in Kleinschirma where it is installing blades on two Enercon E-160 turbines.
