Add to favorites

#Industry News

Putting the ‘walk’ into ‘walk-to-work’

As the 108m ‘Acta Orion’ is to provide an easy ‘walk-to-work’ for technicians rather than a high speed journey followed by a potentially nasty scramble up a wind tower, it’s involved a careful look at the access system.

In fact, owners Acta Marine “had an Ampelmann gangway in mind” from the first Friso Talsma of Ampelmann told MJ, so it’s been integrated into the vessel design, rather than an ‘add on’, with elements like a platform base to give it a little extra elevation in order to provide a near horizontal transfer to the windmill. However, since the system is a plug & play design that comes complete with its own power pack, (dropping installation time to around only eight hours) it can easily be repositioned.

The result is significant rise in efficiency. Standard fast crew boats can only deal with waves of 1.5m Hs – which, given the necessary margins for getting the technicians off the towers again realistically translates into 1.2m or 1.3m Hs. By contrast the Ampelmann on Orion will allow it to continue to work in sea states of up to 2.5m Hs, opening wide the operational window: “We can actually get three personnel safely onto the tower balcony within minutes,” added Mr Talsma.

So while on its first deployment for Van Oord on the Gemini windfarm, Orion will have access via the stern, there is also alternative space for it amidships allowing it to be repositioned between assignments. Both arrangements are viable because the Ampelmann takes realtime measurements of the ship’s motion, compensation coming from six, separate hydraulic cylinders. The result is that the top of the Ampelmann remains completely stationary compared to the structure, even though the access system will have to deal with high sea states and also the larger movements that come from an aft position.

Mr Talsma explained Acta Marine were looking beyond mere installation: “Therefore it’s not just a gangway that Amplemann are delivering, it’s a whole package and that includes the system, the operators, and the back office to ensure a quick response and a continuous online view so that if any issues crop up, things can be tweaked without returning to shore.”

Alongside the personnel transfer, Ampelmann has also cooperated with Acta Marine to develop a fully motion compensated cargo solution, allowing equipment weighing up to 300kg to the wind turbine without a crane. By using the same system with a modified, removable tip, a standard size pallet can easily be picked up. This is the very first vessel to be fitted with the new cargo lifting device and Mr Talsma concluded: “This is, itself, a game changer –this way vessels can increase the operational limit from the usual 1m Hs demanded by cranes to 2.5m Hs seas.”

Details

  • Het Nieuwe Diep 39-d, 1781 AE Den Helder, Netherlands
  • Acta Marine