Dapeng Princess, the world's largest fourth-generation liquefied natural gas carrier for shallow water, was delivered on Feb 18. (PHOTO: sasac.gov.cn)

By LU Zijian

The Dapeng Princess, the largest fourth-generation Liquefied Natural Gas (LNG) carrier to sail in shallow water channels in the world, was delivered on February 18. Designed by Hudong-Zhonghua Shipbuilding (Group) Co. Ltd., and jointly built with China Shipbuilding Trading Co., Ltd., this vessel gives a glimpse of China's progress in becoming an important player in the global shipbuilding industry.

LNG vessel production boosted

Regarded as one of the jewels in the crown of global shipbuilding, LNG vessels are extremely difficult to construct and represent a country's capability of shipbuilding.

During long -distance transportation, LNG needs to be kept at low temperature (-163°C). Invar, the material in direct contact with LNG, is a steel containing 36 percent nickel, which will hardly shrink or deform when the normal temperature drops down to -163°C.

The difficulty is that the invar used on LNG vessels is only 0.7 mm thick for the most part, about the thickness of paper. The total length of welds of a large LNG vessel's enclosure system could reach 150 kilometers, and 10 percent of the welds need to be done manually. All these require high standards in welding technology.

Though China arrived late to the LNG vessel market, it has rapidly grown into a key player. In 2008, Hudong-Zhonghua built China's first LNG vessel, Dapeng Sun, and it was the world's largest thin-film LNG vessel at the time. With its various components maintaining 40 years of fatigue resistance, Dapeng Sun is among the ranks of global "long-life" giant ships.

From the second generation of LNG vessels, Hudong-Zhonghua began to develop and design independently. In 2022, the shipyard began to build the fifth generation, the evaporation rate of which has dropped to 0.085 percent per day from 0.15 percent per day in the first generation, a huge leap forward in this important technical index of LNG vessels.

According to China Association of the National Shipbuilding Industry (CANSI), China's international market share of new orders for large LNG vessels exceeded 30 percent for the first time in 2022.

Cruise in the making

Large LNG vessels have realized mass production in China, and the first large cruise ship built is to set sail at the end of May, according to China State Shipbuilding Corporation Limited.

The ship is as high as a 24-story building and 87 percent complete. The number of the components in its construction reached an incredible 25 million, five times that of C919, China's first homegrown large jetliner.

In order to control the weight of the hull, the ship used a large amount of steel plates that are a mere four to eight millimeters thin. A smart workshop was specifically built by Shanghai Waigaoqiao Shipbuilding Co., Ltd to make such thin plates, adopting technologies such as laser cutting and laser composite welding to improve the efficiency and precision of the transfer, cutting, processing and construction of the thin plates.

To cope with the massive engineering data of the cruise ship, Shanghai Waigaoqiao independently developed a new generation shipbuilding management platform, turning the traditional construction site drawings into a tablet computer to enable all-time tracking of 25 million parts of the cruise ship from design, procurement, and production, to construction, commissioning and delivery.

Li Yanqing, secretary-general of CANSI, said that once the construction of the cruise ship is completed, China's shipbuilding industry will be able to build all the marine vessels and platforms in the world.

Shipbuilding's good prospects

According to CANSI, China's shipbuilding international market share has been ranked first for 13 consecutive years until 2022.

Among the 18 major ship types in the world, China topped the new order list in 12 ship types. In particular, new orders for bulk carriers, container ships, car carriers and crude oil tankers made up 74.3 percent, 56.8 percent, 88.7 percent and 66.1 percent respectively.

Top Chinese shipbuilding enterprises maintain a strong international competitiveness, as six of them are in the worlds' top 10 in terms of shipbuilding completion, new orders and handheld orders.

New breakthroughs in high-end equipment have also been achieved, especially in the field of high-tech ships and marine engineering equipment.

The world's first dual-fuel main engine, with intelligent control of exhaust gas recirculation system, has also been delivered. In addition, large intelligent fishery breeding ships at 100,000-ton level, the fourth-generation self-elevating wind power installation vessel and other offshore engineering equipment were delivered.

In the following three to four years, China's shipbuilding enterprises will welcome the peak period of delivery, while shipbuilding enterprises will focus on quality and safety, and ensure the delivery of handheld orders on schedule.