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Daewoo readies prototype Yamal icebreaking LNGC for action

Mon 20 Jun 2016 by Mike Corkhill

Daewoo readies prototype Yamal icebreaking LNGC for action
Breaking ice in the stern-first mode, the Yamal LNGCs will require no icebreaker escorts

The world’s first icebreaking LNG carrier is now nearing completion at Daewoo Shipbuilding & Marine Engineering (DSME). On order to Sovcomflot (SCF), the 172,000m3 Christophe de Margerie, or DSME Hull No 2418, is the first of 15 such vessels being built at the yard for Russia’s Yamal LNG project and is set to open up a new chapter in LNG shipping.

Although there are 11 ice class LNG carriers in service, none is able to move through thick ice in traditional icebreaking mode. The existing ships are all Arc4, or ice class 1A, vessels, with hulls and propulsion systems designed to handle ice thicknesses not exceeding 0.8m.

Hull No 2418 and the rest of DSME’s Yamal series are being constructed to Russian Register Arc7 ice class, equivalent to a level between the new Polar Classes 3 and 4. The design will enable the ships to proceed through ice up to 2.1m thick on a continuous basis and load cargoes at Yamal’s Sabetta terminal, high in the Russian Arctic, year-round without the need for dedicated icebreaker escorts.

Russia’s Novatek and its project partners Total, China National Petroleum Corp (CNPC) and the Silk Road Fund of China are developing Yamal as a three-train scheme with an aggregate LNG production capacity of 16.5 million tonnes per annum (mta). The US$27 billion initiative is scheduled to commence commercial operations late in 2017, thereafter building to full production by 2020.

Sabetta is located on the Yamal peninsula’s Ob Bay in northwest Siberia, well inside the Arctic Circle. The Kara Sea site poses special challenges: temperatures of -40˚C are not uncommon during the winter months and waters around Sabetta are ice-covered for approximately 300 days a year.

 

Yamal fleet

Ownership of the Yamal fleet is split amongst a number of players. In addition to SCF, and its involvement with the lead vessel, Teekay will operate six ships, Dynagas five and Mitsui OSK Lines (MOL) three. The full fleet will be jointly classed by BV and the Russian Maritime Register.

Chinese partners will hold stakes in the Teekay, Dynagas and MOL ships and the last of the 15 icebreaking vessels is due for completion by early 2020.

Yamal LNG has also provisionally agreed to take up to six existing Dynagas Arc4 LNGCs in the 150-162,000m3 size range on charter. The sextet would be utilised in the delivery of LNG to Asian customers from 2019 for a minimum of 15 years.

Global warming has led to a shrinking of the Arctic ice cap over the past two decades, to the extent that vessels of a lesser ice class are eligible for employment in northern polar waters at certain times of the year. For example, the Russian maritime authorities will allow ships with ice-strengthening to class 1A to operate on the Northern Sea Route (NSR) if they fulfil additional requirements regarding crewing and icebreaker assistance.

Dynagas is as yet the only owner to have sailed an LNGC on the NSR, its 150,000m3, Arc4 Ob River having made the transit, with an icebreaker escort for part of the journey, in November 2012.

 

Super carriers

Yamal’s 15 icebreaking LNGCs are being built to the double-acting ship (DAS) design developed by Aker Arctic in 2003 for a pair of 110,000 dwt oil tankers for use in Neste Shipping’s Baltic Sea operations. The DAS technology enables ice class vessels to proceed in the conventional bow forward direction in open seas and thin ice but astern in thicker ice and the full icebreaking mode.

Astern icebreaking operations on the Yamal LNGCs will be assisted by a heavy-scantling, aft hull structure and a podded propulsion system. Each ship will employ six Wärtsilä dual-fuel engines, comprising four 12-cylinder and two 9-cylinder 50DF units. The complement is able to deliver up to 45MW of power to the three ABB Azipod propeller units on each vessel.
Wärtsilä engines were considered as being the most suitable for handling the extreme engine load variations that can occur within a short timespan when a ship is proceeding through thick ice.

The Azipod units also facilitate icebreaking operations. When a podded ship runs astern in ice, the propellers mill the underwater part of the ridge, cutting a passage through, and at the same time generating a flow of water flow which flushes the hull, facilitating progress through the ridge field.

 

Prototype pioneer

Christophe de Margerie will serve as the Yamal LNG fleet prototype vessel. Construction work at the DSME yard is now virtually complete and sea and gas trials are due to commence in July. The vessel is set to depart Korea in October to undertake an ice performance testing programme prior to delivery to SCF on 31 January 2017.

The final stages of the commissioning phase will enable all the participating owners in the Yamal LNG fleet to assess the efficacy of the Arc7 ship design in the harsh winter conditions that pertain in the Russian Arctic in December and January.

While the performance of the ship’s propulsion units, ice-strengthened hull and reinforced GTT No 96 membrane containment system will be a primary focus, also under scrutiny will be the ability of the cargo-handling equipment, navigation systems and winterisation features to cope with the Arctic environment.

Prior to and post-delivery, Christophe de Margerie will also be utilised for training the crews of the other Yamal icebreaking LNGCs. SCF affiliate Unicom will manage the ship and will make use of the group’s decade-long involvement in both gas carrier and ice class operations.

Besides Hull No 2418, SCF holds ownership stakes in and is responsible for the technical management of eight LNG carriers and four LPG vessels. The company also operates a fleet of 112 oil tankers, a number of which are ice class vessels engaged in Arctic projects.

In 2010 the group’s SCF Baltica, an ice class 1A Aframax tanker of 116,000 dwt, became the first large commercial vessel to make the high-latitude voyage from the Atlantic Ocean to the Pacific along the NSR’s 2,150 nautical mile (4,000km) route.

SCF also has experience of DAS icebreaking operations, through its three 70,000 dwt Vasily Dinkov-class shuttle tankers that have been serving the Varandey terminal in the Barents Sea since 2008. These double-acting ships require no icebreaker escorts.

The work of the Unicom project team that has been at DSME supervising the construction of Christophe de Margerie is just about complete. Next, it will be the manager’s specially trained crews who’ll be putting this breakthrough vessel through its Arctic paces and paving the way for the delivery of Yamal LNG to customers worldwide.

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