Korea’s shipbuilding industry is accelerating efforts to widen the technology gap with China in liquefied natural gas (LNG) carriers. LNG carriers are a representative high value-added vessel, and Korean shipbuilders with advanced technology lead the global market, but Chinese companies have been catching up quickly in recent years.
On the 28th, the shipbuilding industry said HD Hyundai’s institutional sector affiliate HD Hyundai Samho is building a 177,000-cubic-meter LNG carrier with three cargo tanks at the Yeongam shipyard in South Jeolla. A standard LNG carrier typically has four cargo tanks and a capacity of 174,000 cubic meters. The vessel HD Hyundai Samho is constructing is seen as a model that can increase LNG loading volume and boost transport efficiency.
This vessel reduced the number of cargo tanks to three while increasing loading capacity by 3,000 cubic meters. By cutting non-cargo structures and equipment that used to go between tanks, it rearranged internal hull space, and the length of each individual cargo tank was expanded by up to 55% compared with the 174,000-cubic-meter class.
Reducing the number of cargo tanks on an LNG carrier by one requires demanding construction methods and safety verification. The fewer the cargo tanks, the larger each tank becomes, which intensifies the “sloshing” of LNG inside the ship. When sloshing occurs, LNG can strike internal structures of the cargo tank forcefully and damage the cargo tank system.
This is the first time a Korean shipbuilder has built a large LNG carrier with a “three-tank configuration.” Chinese shipbuilders have obtained technology certification for the three-tank configuration, but have not yet built a vessel. In 2023, Hudong–Zhonghua Shipbuilding received technology certification for a 174,000-cubic-meter three-tank LNG carrier from five major international classification societies, including the American Bureau of Shipping (ABS).
The case is being assessed as a technology that will bolster Korean shipbuilders’ competitiveness in LNG carrier orders going forward. The vessel offers high LNG transport efficiency and can also lower construction costs, which can offset Korean shipbuilders’ price disadvantages versus Chinese rivals.
Ships that transport LNG from the United States and the Middle East to Asia and Europe need the efficiency of carrying more cargo within fixed dimensions in a single voyage to cut fuel consumption and shipping costs. This vessel has about 3,000 cubic meters more capacity than the four-tank configuration on the same 177,000-cubic-meter hull. With the same ship size, it can load more LNG and reduce transport costs.
With the number of cargo tanks reduced to three, the materials used to build the tanks and the royalties paid to France’s GTT, which holds the core cargo tank technology, are also expected to decrease. Korean shipyards pay GTT license royalties for cargo tanks. It is generally known to be around 5% of the cargo tank area. Reducing the number of cargo tanks eliminates one cofferdam, the space between tanks, yielding a reduction in total area.
Ryu Min-cheol, a professor at Korea Maritime and Ocean University, said, “Building three cargo tanks implies higher pressures could occur, which suggests HD Hyundai has found a safe construction method,” and added, “On the assumption there are no safety issues, the surface area would be smaller than with four cargo tanks, reducing the amount of materials and allowing the ship price to come down further.”
Localization of LNG cargo tanks is also gathering pace. Localizing cargo tanks is cited as a key task to improve shipbuilding profitability by cutting expense by the amount of royalties paid to GTT. The government last year selected the localization of LNG cargo tanks as one of the “15 ultra-innovation economy leading projects” and is accelerating technology demonstration.
Previously, there was one round of “first-generation cargo tank technology” development in Korea. The Korea-style LNG cargo tank model “KC-1,” developed in 2004 led by KOGAS subsidiary KLT, progressed to the demonstration stage. During testing, however, a “cold spot (icing phenomenon)” occurred in which the outer wall temperature of the cargo tank fell below the allowable range, halting ship operations and derailing commercialization efforts.
Development of second-generation cargo tank technology is now accelerating. The three major shipbuilders have each been pursuing domestic cargo tank technologies. Samsung Heavy Industries received technology certification for its in-house cargo tank technology, KC-2C, from DNV of Norway and three other international classification societies. HD Hyundai Heavy Industries obtained certifications from Lloyd’s Register of the United Kingdom and the Korean Register, while Hanwha Ocean received certifications from five societies including DNV.
Korea Gas Corporation (KOGAS) plans to place an order within this year for a vessel to demonstrate second-generation cargo tank technology. The technology of the shipbuilder selected in the bidding competition will proceed through actual demonstration.
Source: Chosunbiz
