A turbine of this size can produce over $1,000,000 of electricity annually. With the replacement motor’s estimated lead-time being 6-months or more, this repair could easily be a savings of up to half-a-million dollars.
A Decatur Industrial WIND customer had a motor damaged during installation. The motor suffered a broken stator foot and a replacement motor from the OEM would not be available for many months. The foot and stator yolk are cast as one piece and not replaceable without replacing the entire stator yolk assembly. The customer engaged us to find a way to repair the motor so it could immediately go back into service.
Decatur Industrial machinists knew that without all four mounting feet on the motor it was unusable in the application, preventing the turbine from operating. Our team got to work machining the entire side of the stator with the fractured foot. We milled the yolk to remove the remainder of the damaged foot support structure. We also removed the rear foot on the damaged side of the stator along with the support structure. A complete new front and rear foot assembly with support structure was machined to fit the stator. The foot had to mount precisely to the stator and provide the exact footprint with bolt pattern to allow the motor to bolt into the turbine. We installed the new foot assembly and then replaced the damaged bearings. The motor was fully assembled, test run, and shipped to the wind farm. The farm installed the repaired motor which enabled the turbine to come back on-line, producing power for customers.