The Dörries large gantry with movable table is designed for swing diameters up to 15mHACO A/S, a Danish family-owned company, has installed a second large machine that can process very large workpieces in a single-clamping operation. Supplied by
Starrag, which has a UK subsidiary in Birmingham, this machine allows HACO to process massive rotor housings and brake discs for offshore wind turbines in the 14 to 15MW class more efficiently and precisely than was previously possible.
This latest investment in a very large Dörries gantry machine with a fixed gantry and sliding base, complements a Droop+Rein gantry machine with a travelling gantry that was installed earlier and has been running since the beginning of 2024; and despite their differences, both machines share the same core components, simplifying maintenance and operation. Moreover, this latest gantry machine significantly expands HACO’s machining range, thanks to its enhanced main drive and increased swing diameter of the workpiece. Indeed, HACO can now manufacture larger welded rotor housings and other substantial components with precision.
Hubert Erz, a senior sales consultant for renewables at Starrag, said: “Our two large machines are two true giants and now in production. We are setting a new benchmark in machining workpieces for gearless wind turbines in the 14 and 15MW power classes, and here the focus is primarily on rotor housings, generator housings and brake discs, which currently have a diameter of around 9m and are manufactured within a tolerance of ±0.1mm.
“The two 870-tonne machines required a foundation capable of withstanding the enormous static and dynamic loads necessary for precise machining, so during the design phase Starrag implemented extensive assembly and handling precautions to ensure that these substantial components could be transported and aligned accurately. A central feature is the ‘two-storey basement’, which not only provides a stable base but also facilitates access to central components.”
Henning Albrechtsen, HACO’s managing director, added: “Our machined components, from rotor housings, brake discs and stator laminations, remain predominantly welded workpieces that will be manufactured in larger dimensions in the future. At the same time, our product portfolio has expanded. In addition to traditional parts, we now also machine castings, such as generator housings and adapter components for connecting the nacelle and tower. These latest investments put us in an ideal position to meet the requirements of the next generation of wind turbines.”