Astraeus Wind Energy says its MAG MEGAFLEX machining system has passed its initial supplier qualification by completing ‘Operation 20’ metal-cutting processes on a Clipper Windpower C96 turbine hub.
The system simultaneously machines all three blade faces, which enabled it to complete the qualification hub in less than one shift, Astraeus says.
The 18,144 kg (40,000 lbs.) spherical hub was approximately 3.6 m x 3.6 m (12 ft x 12 ft) in size, with a blade bolt circle of about 2.5 m (8.2 ft). Operation 20 for this part included milling the blade faces, drilling and tapping or counter-boring more than 60 3 mm (1.5 in) holes per face, boring and drilling the blade-pitch gear mounting surfaces, and cutting various other features.
Tolerances on the part, which was laser-inspected after machining, include 0.05 mm (0.002 inch) true position on holes and Â±1 degree on angles.
The patent-pending MEGAFLEX design, which is based on three MAG FTR 5000 floor-type boring mills surrounding a B-axis rotary table, simultaneously machines all three blade faces on a wind turbine hub in one setup, Astraeus adds.