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9.3 Tower design
The upper part of the guyed tower design is shown on figure 9.6:
Figure 9.6: Illustration of the upper part of the tower
TOWER
The tower (1) is a ø168.3x7.1 mm steel pipe with a length of 11.3 m. A flange (2) is welded
onto the top of the pipe, providing an interface for the yaw system. Due to the height of the
tower it may be necessary to weld the tower from shorter pieces of pipe.
The tower is mounted with three guy wires (3) in two levels. The upper attachment brack-
ets (4) are positioned as high up the tower as possible, but below the blade radius, as to
prevent collision between the brackets and the rotor blades during operation. The upper
guy wires are attached at an angle of approximately 30� to vertical while the angle for the
lower guy wires is approximately 50� to vertical. The lower brackets are positioned half-
way between the upper brackets and the ground with the intention of preventing buckling
of the tower. With a height of 12 m the foot-print radius of the guy wires is approximately
6 m.
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