This conceptually innovative tower design developed by Siemens, Andressen Towers and Tension Control Bolts Ltd provides a economically viable tower for wind turbines above 100 m. The TCB bolted Steel Shell Tower is suitable for higher towers up to 140 Metres. Significantly increasing the energy yield of a wind turbine generator on sites with a high wind shear.

There are 300 of this tower design across Northern Europe primarily in Sweden, Denmark and Finland. The Bolted Steel Shell Tower consists of multiple tower sections.

Each section fabricated from steel ‘shells’ which are transported and then assembled together on site. A standard truck can be used to transport the sections in this ‘flat-pack’ design. The sections are bolted together with TCBs (HRC / tension-controlled / Tension Control Bolts) bolts to form a tower section.

Advantages :

  • Fast and easy installation using tension-controlled TCBs with tower erection completed within a couple of days.
  • Utilising TCBs means there are no welded connections, problems with fatigue and cracks are avoided.
  • High hub heights; virtually no restriction on the maximum hub height.
  • Low transportation requirements.
  • Super quick erection in a couple of days.
  • Minimal maintenance - In fact, the TCBs require no re-torquing during the tower’s lifetime. Research from the Fraunhofer Institute allied to the University of Rostock engineering faculty verified that Greenkote TCBs from Tension Control Bolts will not lose pre-load after correct installation. In simple terms the TCBs are maintenance free and will outlive the design life of the tower. These towers are almost always located in remote areas.
  • Reduced steel requirement; in contrast tubular steel towers have larger tower diameters with thicker steel material.
  • Utilises steel coils which are more cost effective than quarto steel plates.
  • Highly automated shell production ensuring consistent high quality and reduced costs.
  • Easy transportation of shells on standard trailers, in containers or by rail, facilitating access to even remote locations.
  • Fully recyclable tower at end of life.
  • Highly effective corrosion protection; Greenkote® TCBs from Tension Control Bolts Ltd have the C5-M approval for highly corrosive environments; typically marine, coastal and off-shore applications as well as the German Ü mark for construction products administered by DIBt (German Institute for Construction Technology) and shows that the Ü marked product conforms with additional German specifications, on top of European CE markings and again very relevant to highly corrosive applications in the wind energy market.

Greenkote® anti-corrosion protection

Tension Control Bolts Ltd has its own metal coating plant producing an environmentally friendly process called Greenkote®, which is comparable to galvanising, although it is harder wearing and readily accepts all paint systems. Learn more about Greenkote.