Quick release tower seafastening

TWD introduces the quick release tower seafastening to speed up and improve the safety of WTG seafastening operations. The quick release tower seafastening excludes manual handling and ensures instant decoupling of tower and seafastening.

Installing future WTG

Transportation of WTG components requires dedicated seafastening structures on board of vessels. To withstand the transport loads, towers are currently bolted to the seafastening. Depending on the severity of the operational conditions, each bolt must be set at a specific pre-tension. Before lifting the component from the seafastening, the tension on the bolts must be released. Pre-tensioning and releasing of the bolts require extensive manual labour and as turbines are increasing in both weight and size, an increasing number of bolts is necessary to secure the tower to the seafastening.

The market’s tendency to install bigger turbines, in increasingly deeper water depths, introduces challenges regarding installation and transportation of future generation WTGs. To handle the larger turbines, floating installation vessels might prove a feasible solution. Although floating installation vessels provide opportunities concerning crane- and deck capacity, using them requires re-evaluation of the conventional working methods.

To ensure the flange integrity of both tower and seafastening during floating operation a specific level of pre-tension must always be applied, as lowering the tension might result in significant damage to both flanges. Additionally, lowering the pre-tension might result in life threatening situations for the technicians loosening the bolts, as the tower is allowed some movement. To overcome these challenges, TWD introduces a remote operated mechanism allowing for an instant release of the tension; the quick release tower seafastening.

Tower clamp closed

Tower clamp open

Quick release concept

TWD’s extensive knowledge and experience in designing dedicated seafastening structures have been combined in the quick release tower seafastening concept. The quick release tower seafastening provides a solution that excludes the need for a bolted interface between tower and seafastening. By doing so, the quick release tower seafastening excludes manual handling and ensures an instant uncoupling of tower and seafastening.


  • excludes manual handling
  • solution to floating lifts
  • remote operated
  • increases on-board safety
  • excludes bolted interface
  • quick release/fastening mechanism
  • seafastening of full towers
  • ensures controlled lifting (tower guide system)


Tailored design

Contractors have chosen TWD as their preferred seafastening designer on over 50 offshore wind farm projects. Our specialized engineers would be happy to hear your boundary conditions and requirements, to tailor a tower, monopile or TP seafastening to your needs! Find more information on our services here.

Triggered your interest? Visit our stand, E-D18.03 at WindEurope Copenhagen from 26-28 November 2019, and learn more about our engineering capabilities. We look forward to welcome the engineering challenges ahead of us!

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