Next Generation to Break the Ice -The Oblique Icebreaker

Abstract

Abstract In the early 1990's Russia was looking for the possibility to build a new oil export channel from the Timan — Pechora area through a pipeline to a port located in the Gulf of Finland. Various port options were studied and the final export harbour location was decided to be in Primorsk, Russia in the Eastern end of the Gulf of Finland. From Primorsk the crude oil would be shipped to commercial markets by tankers Already at that time it was seen that the increased oil transportation in the Baltic Sea would mean larger size tankers. This led to new requirements for the of icebreaking operations to assist the vessels, which are wider than the assisting icebreakers. With the existing icebreaker fleet two icebreakers are needed to create wide enough channel for one tanker. To avoid using two icebreakers and reduce the operation cost, one vessel would need to be able to make both wide and narrow channel. The oblique icebreaker concept was developed in the mid 1990's by Aker Arctic (at that time Kvaerner Masa Yards Arctic Research Centre - MARC). The idea is to use one single vessel with two operational modes; normally bow / stern ahead or in an oblique angle. This would enable the vessel to create both narrow and wide channel. The oblique operation would mean that the ship hull is not symmetric. The general requirements in asymmetric ship design has forced to new thinking also in other areas, which in turn has re-opened the commonly used solutions and designs. The new unconventional concept has opened wide range out-of-the-box possibilities also in other areas, such as oil spill combatting, ice management in harbours and offshore. The novel concept has seen many stages of development and now it is becoming reality as Russian Ministry of Transportation decided to order the first oblique icebreaker in 2011 for Baltic operations. The first vessel (NB508 at Arctech shipyard) is under construction, when this paper is being written. The operation of the new concept will also be a learning process for the captains and will in time further reveal new possibilities for the vessel use. Experience from the design of the Baltic version is used to further develop the concept for Arctic use. The Arctic version was introduced to public in May 2013. This paper shows the technology behind the vessel under construction and also shows major principles of the concept and introduces the new possibilities of the oblique ship concept.