A leading manufacturer of wind turbines relies on eldec technology. The short-circuit rings in the electric motor of a machine are processed using induction brazing. The entire part benefits from the process quality of this application.
Process reliability when brazing short-circuit rings
Wind turbines are exposed to special stresses: For example, while a car engine is designed for a maximum of 6,000 hours, a wind turbine must survive about 120,000 hours of operation without damage – equivalent to 20 years without stopping. This means that every single part – and especially the electric motor of a wind turbine – must comply with extremely demanding quality requirements.
Under these circumstances, a leading manufacturer of wind turbines now relies on induction brazing technology from eldec. Experts use this precise and reliable method for attaching the short-circuit ring to the lower end of the machine’s generator. The inductor produced by eldec heats the ring to between 680 and 720 °C. The phosphorus-based solder melts and joins the short-circuit ring to the outside of the generator with several copper bars. Engineers from eldec and the wind turbine manufacturer jointly designed this process, which takes approximately four minutes, and perfected it in tests.
The greatest benefit of the application becomes evident when looking at the brazed seam: It exhibits very little oxide formation and therefore has a very high quality. Another benefit is that very little heat dissipates into the rods, which virtually rules out distortions of the part.
The generator as the energy source has special significance for induction welding. A medium-frequency model from the eldec CUSTOM LINE Series with 250 kW power is used in this case. Frequency ranges are between 10 and 25 kHz. The individually configured, robust generator ultimately ensures a stable production process and low energy consumption.