Saga debut for new LNG cargo system
Bringing a first-of-kind containment system and vessel concept to the LNG transportation market, the 45,000m3-capacity ‘Saga Dawn’ is being readied in China for handover soon to a young, Singapore-based company with Sino-Norwegian roots
Ordered from the Haimen yard of China Merchants Heavy Industry in eastern Jiangsu province, the vessel features self-supporting, IMO Type A tanks mounted within an insulated hold space, writes David Tinsley. The patented system, named LNT A-BOX, was developed by LNG New Technologies (LNT), an affiliate of contractual owner Landmark Capital, in conjunction with Swedish ship designer FKAB.
LNT’s rationale has been to devise a comparatively simple, cost-effective containment method that would open up construction of mid-size LNG carriers to a wider range of shipyards, especially those in China, and bridge the gap between smaller ships with Type C tanks and those with larger membrane-type containment systems.
LNT has provided engineering services for the newbuild project at Haimen, and is marketing the patented LNT A-BOX solution, and in a range of sizes, to other, potential licensee yards looking to enter the LNGC sector.
Saga Dawn will be operated by Saga LNG Shipping, which is also owned by Landmark Capital, a Singaporean company and financial advisory with its base of operations in Shanghai. Thome Ship Management is Saga LNG’s partner for pre-delivery procedures, crewing and technical management.
The vessel is powered throughout by Wärtsilä dual-fuel machinery and employs a comprehensive Wärtsilä drive train and engineering package. A single 12V50DF main engine, rated at approximately 11,700kW, drives a controllable pitch propeller through a reduction gearbox. Running at 8,250kW power on the design draught, the tanker is expected to make just under 17 knots. The two auxiliaries, comprising six- and eight-cylinder models of the L20DF series, give a total output of some 2,500kW, and can also run on LNG fuel.
Wärtsilä was also contracted to supply the complete cargo handling plant, incorporating an integrated fuel system utilising both compressors and forced vaporisation. The cargo section is divided into three tanks, of 0.6t/m3 design density and 0.4 bar maximum allowable relief valve setting (MARVS). The boil-off rate for the LNT A-BOX system is given as about 0.15% per day.
Applying proven technologies in a new configuration, LNT A-BOX consists of IMO type A independent, prismatic tanks forming the primary barrier, a conventional cargo tank support system, and liquid-tight, thermal insulation attached to the inner hull surface acting as a full secondary barrier. The insulation system was supplied by MGI Thermo. Six cargo pumps promise full-load discharge within 15 hours.
The void space between the tank and insulation facilitates visual inspection of both tank and insulation surfaces. The design is intended to obviate any restrictions on partial loading, a vitally important factor for the planned operating profile of the ship and its intended primary role in coastal and intra-regional trading.
LNT A-BOX is seen as core to the future fleet development strategy of Saga LNG Shipping.
PRINCIPAL PARTICULARS—Saga Dawn
Deadweight @scantling draught
Deadweight @design draught
Main engine power, MCR
LATEST PRESS RELEASES
As of November 2018, SCHOTTEL Norway AS and Frydenbø SCHOTTEL Nordic AS have been merged under SCHOT... Read more
The First Integrated Navigational Planning and Route Optimization Platform Delivered by One Company Read more
Sofia Fürstenberg Stott has been an architect of Nor-Shipping’s evolution to embrace and enable new ... Read more
Nor-Shipping is aiming to set a new benchmark for the maritime and ocean event segment with a move t... Read more
Located in the Netherlands, Intertech B.V. is now Datum Electronics’ representative for torque senso... Read more