In the large family of civil ships, there are two high-end ships that are recognized in the world as "the crown jewels" of the shipbuilding industry, one is a luxury cruise ship and the other is an LNG (liquefied natural gas) ship. LNG ships are called "Big Macs", and they are called "super freezers at sea". They are special ships that transport liquefied gas at -163 ℃. Its high technology, high difficulty and high added value are internationally recognized. There are only a few countries in the world that can build LNG ships, and Invar, which is the core material of LNG ships, is also known as the "Pearl in the Pearl." Previously, only one company in the world could produce it. At present, this global exclusive monopoly is being broken by China BGTG Special Steel Group. BGTG Special Steel has recently passed the French GTT company's certification of LNG marine Invar, becoming the world's second qualified supplier to supply thin film LNG marine Invar.
French GTT company (Gazt ransport · Technigaz) is an engineering company specializing in the research and development of low temperature storage and transportation technology of liquefied natural gas. It has more than 60 years of experience in manufacturing LNG storage tank membrane sealing systems. The French GTT company has a number of patented technologies for thin-film LNG tanker tankers. All materials used in thin-film LNG ships need to be certified and licensed by the company.
As a major power tool, the first LNG ship manufactured in China in April 2008 was successfully undocked, marking the rapid rise of Chinese shipyards in the field of LNG ship construction. However, as the core material of LNG ships, Invar alloys always rely on imports, the main reason is that it is too difficult to develop. In thin-film LNG ship maintenance systems, Invar alloys are widely used as thin-film materials, such as paper, with a thickness of 0.7 mm. They are ultra-low temperature resistant special steels with an operating temperature of -163 ° C. These data show that the technical difficulty of its development is far beyond imagination.
As early as four years ago, the project “Key Technology Application Research of LNG Ship Invar and Insulation Box Plywood” by the Ministry of Industry and Information Technology led by Hudong Zhonghua Shipbuilding (Group) Company was officially launched. Development of Invar alloys. Facing the challenges, BGTG Central Research Institute Special Steel Technology Center and Welding and Corrosion Research Institute, BGTG Special Steel Steelmaking Plant, BGTG Hot Rolling Plant, BGTG Special Steel Strip Plant and other departments worked hard to overcome difficulties and break foreign technology Barriers, successfully completed the industrial trial production of this alloy, and achieved stable physical properties and good strength and toughness under ultra-low temperature conditions (-196 ° C). Subsequently, BGTG Special Steel actively contacted the French GTT company with a thin-film shipbuilding technology patent to carry out the certification work. After two rounds of strict certification in 2015 and 2017, it finally completed the plant certification and LNG actual ship simulation verification. French GTT company recently dispatched a special certificate for BGTG Special Steel on the spot, and China Classification Society also issued an LNG marine Invar alloy strip certification for BGTG Special Steel at the same time. So far, BGTG Special Steel has become the world's second qualified supplier of thin-film LNG marine invar alloys while realizing the localization of LNG marine invar alloys.