-45℃ weld seam still has high safety
Recently, Posco and external companies have successfully developed steel pipes for hydrogen transmission, which will be used in Ansan, the first hydrogen demonstration city in South Korea. A hydrogen demonstration city is an environmentally friendly city that uses hydrogen energy for residential facilities and transportation. The Korean Ministry of Land, Infrastructure and Transport designated Dingansan City, Ulsan Metropolitan City, Jeonju, and Wanzhou City as hydrogen demonstration cities in 2019. Up to now, South Korea's hydrogen transmission pipelines mainly use imported seamless steel pipes under 6 inches. However, due to the large amount of hydrogen transmission in South Korea's hydrogen demonstration cities, the South Korean Ministry of Land, Infrastructure and Transport has adjusted the design plan to a large-diameter pipeline with a diameter of 8 inches. Generally speaking, welded steel pipes are used for large-diameter steel pipes above 8 inches, but due to safety issues in the weld zone, the application is limited. In response, Posco developed a new steel product that significantly improved the service life and safety of the weld, and was able to cope with cracking and corrosion caused by hydrogen, and commissioned Husteel to manufacture the steel pipe. When this type of steel pipe is at -45°C, the weld seam also has high safety and can resist external impact.