arctic


icebreakers or ice classed vessels and barges, or the so-called Wagenborg “Ice train” which deploys a dedicated barge connected to an icebreaker, which travels stern first. By using an icebreaker and two barges up to 4,500 tonnes of cargo can be transported.


More than a decade on, Wagenborg has a substantial presence in Kazakhstan with 28 units operating there, including tugs, barges and offshore accommodation units for 2,000 people and it can boast an impressive 45,000 hours operating in shallow, ice-infested waters.


And in November, Wagenborg’s two latest eagerly anticipated ice breaking support vessels launched from Royal Niestern Sand- er Shipyard (also part of the group).


extremes ranging from minus 40 degrees Celsius to plus 40. And coupled with that, it is an area with a very shallow draught ranging from only 1.5 m to 5 m.”


Typically there is first-year moving ice of 60-70 cm in the Kashagan field and this is almost fresh water ice, with little salt content, he emphasises, making the ice very strong. “Given the wind and currents in the winter there are significant forces on the hull and propulsion equipment. There is also the pressure of the well and the presence of the lethal gas H2S.”


Extensive experience However, Wagen- borg did not shy away from the challenge. “We knew we had extensive experience and the right knowledge in-house. We had been shipping for more than 100 years in ice-infested waters. Subsidiaries, Nedlift and Foxdrill had been providing supporting services to the on and offshore oil and gas industries. We had been providing ferry services in the Wadden Sea, known for its shallow waters and environmental sensitivity for over 100 years. We had the


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knowledge there but had to combine it to take on this challenge.”


This led to the decision to build two dedicated ice breaking supply vessels specifically designed for shallow waters in 1998 at Kvaerner Masa Yards in Helsinki. Wagen- borg – which designs nearly all of its vessels itself – knew that conventional ice- breaking techniques combining the weight and power of a vessel would not work because these would not get the vessel over an ice ridge. “A different approach was needed to penetrate these grounded ridges.”


Therefore a special shallow draught hull design, combined with an Azipod thruster emerged. This had the capability to break ice of 1m, unusually travelling stern first, effective- ly “eating the ice away”. These two vessels – the Antarcticaborg and Arcticaborg – also embodied a zero dumping philosophy.


Two newbuild icebreakers A unique supply method to this remote area was also needed, he says. Transport by a dedicated supply vessel was possible; a convoy using


Instrumentation campaign These two newbuilds - Sanaborg and Serkeborg - are ideally suited for the conditions of Kazakh- stan, the Pechora Sea and Yamal Peninsula, Russia or Canadian waters. One is likely to go to Caspian and the other to the Russian Arctic. From design to completion, the ves- sels have taken two years.


Sanaborg and Serkeborg are more efficient than the existing vessels because of the new propulsion and hull form. They also have a decreased draught and beam and increased length. The two have unique ice class thrusters developed together with Wärtsilä. The new Icepod® is suitable for ice milling, “washing and breaking the ice”. MARIN car- ried out the verification of the bollard pull of the thrusters and will be involved in the extensive instrumentation campaign on the new vessels (see separate article).


Mr Derks is optimistic about the many pos- sibilities in the North Caspian, Russia and Canadian Arctic but he also warns that it is an extremely difficult and challenging, environmentally sensitive area - often more difficult than the industry thinks. “It is es- sential to take a long-term view. We need to work with model testing for open sea conditions and in ice, it is vital to work closely together; the yards, owners, their clients (the oil majors) and research institutes to get the optimal result.”


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