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by ship motion and thermal

Vessels cycling and proved its liquid leakage protection for a con- tinuous 15-day period.

Raising the future through the past

SPB technology ? rst entered service in 1993 aboard Polar

Eagle and Arctic Sun, a pair of ABS-classed vessels built at the IHI shipyard in Aichi.

Although only two vessels were built with the SPB system, their record during 20 years of nonstop service

ABS-classed , the world’s ? rst LPG FPSO.Sanha on one of the world’s most results in the kind of ? at-deck vessels 1964,when the ? rst purpose-built LNG severe and challenging runs thoroughly needed for ? oating processing plants carriers, ABS-classed Methane Progress proved the strength and durability of the

While JMU was not the pioneer of this and Methane Princess, entered service. tank design. The shipbuilder now sees an technology, the company applied sophis- These vessels used an update of the opportunity for its containment technol- ticated computer analysis capability to prismatic Type A concept developed by ogy to take an important place in emerg- redevelop and improve on the original the Conch Co. The inner hull was lined ing LNG markets and applications. concept to make it work as a Type B tank with insulation, and the tanks rested on This design eliminates the sloshing and incorporated it in the Sanha, the wooden support blocks. problem and has proven capable of world’s ? rst FPSO for LPG. IHI began building prismatic Type A handling partial loading under extreme tanks for LPG, ammonia and ethylene sea conditions. This makes it a viable

A history of LNG containment carriage in 1960. After making a name in candidate for ? oating terminals, where

The ? rst maritime LNG containment those sectors, the company focused its tanks are constantly in a state of partial system was a prismatic tank of the Type engineering efforts in 1980 on the chal- ? lling.

A variety, installed in a World War II-era lenge of evolving the Conch concept into Internally, the tank is modeled on cargo ship converted for gas carriage a freestanding or self-supporting Type conventional bulk liquid cargo holds – a under ABS class in 1958. Renamed B tank. Rigorous studies were made to stiffened plate structure subdivided into

Methane Pioneer, the ship carried LNG substantiate the design, including ship four spaces by a centerline liquid-tight from Lake Charles, Louisiana, to the motion analysis, FEM (? nite element bulkhead and swash bulkheads. As in

The SPB “Type B” tank was developed in

Canvey Island terminal in England. The method) analysis of the tank and hull, a traditional bulk liquids carrier, the

Japan by IHI and received AIP from ABS success of that conversion – the vessel ? ne-mesh FEM analysis of local struc- bulkheads control the natural frequency in 1983. Photo from ABS .Surveyor remained in service for a decade and tures, fatigue analysis and crack propaga- of the cargo. By preventing ship motions ? nished up doing LPG storage – may tion analysis. Even the insulation system, from creating resonance with the liquid, have signi? cant repercussions in light of which is not load-bearing, was subjected they eliminate sloshing problems, and today’s changing gas markets. to extensive model tests. The tests further the capability for partial loading allows

Another ancestor of the SPB tank demonstrated the suitability of the sys- a ship to quickly leave the berth in the made LNG transport a global business in tem to withstand dynamic loads caused event of an emergency.

LNG projects on the rise at locations in 30 countries at the beginning of April 2014. And

By Stephen Gordon, Clarkson Research growth in this sector is expected to continue. There are 16 LNG liq-

Rapid development in the LNG sector underscores the signi? cant uefaction plants under construction, with a further 27 projects that role technology will continue to play in the natural gas industry and have received FID or are at the FEED stage. These developments, energy markets. LNG shipping has grown signi? cantly over the last along with other potential projects, are expected to support ? rm 20 years, accounting for 32% of all natural gas trade in 2012 – up trade growth over the long term, despite short-term delays to proj- from 24% in 1990. Between 1990 and 2012, LNG trade increased ect startups. It is worth noting that there is signi? cant potential for by a compound annual growth rate of 7.2% compared to 5.4% per export growth in the US and Australia. annum for pipeline gas and 2.4% for global gas demand over the Global numbers for 2013 indicate Asian nations accounted for same period. Global LNG trade increased from 52 million metric three-quarters of global LNG imports, with Japan, South Korea, tons (mmt) in 1990 to 222mmt in 2010. By 2013, trade volumes had India, China and Taiwan ranking as the top ? ve LNG import desti- increased to an estimated 244mmt. nations. LNG trade routes between countries have multiplied as

At the end of 2004, only 10 countries were exporting LNG. At the well, increasing from 45 in 2003 and 93 in 2008 to 168 in 2013.

beginning of April 2014, there were 17 countries (with 89 liquefac- Changes in the global LNG carrier ? eet also re? ect an expansion. tion trains) that have LNG liquefaction infrastructure. The total In 1996, the ? eet stood at 90 ships, nearly doubling to 174 by the production capability of these units is estimated at 293mmt per start of 2005 and rising to 361 by the start of 2011. Today, the ? eet annum. Qatar remains the largest exporter, with volumes reaching stands at 392 vessels. 78mmt in 2013, equivalent to one-third of global exports. With the global demand for gas escalating, the LNG industry is

The import side of the LNG business comprised 107 facilities poised for continued growth. • oedigital.com oedigital.com July 2014 | OEJuly 2014 | OE 6565 064_OE0714_Vessels1_ABS.indd 65 6/20/14 5:14 PM