Demands of double wall piping has been increasing due to the increase in orders for eco-friendly fuel propulsion ships in accordance with IMO's environmental regulations. Marine double piping is divided into engine piping and hull piping, and our company acquired the certification and production facilities to produce all marine engine and hull double piping. The production of vacuum insulated double piping for liquefied fuel was carried out as an R&D task, and the quantitative goals of vacuum degree and BOG were achieved.