Design Aspects of Winterized and Arctic LNG Carriers: A Classification Perspective

It is anticipated that Russia will be one of the major suppliers of LNG to meet energy demand in Europe and in the United States in the future. As a result, large quantities of gas will be transported from Russia through seaborne trade by LNG ships. Due to the geographical location of large gas fields in Russia, these LNG ships will need to be designed to specifically operate in severe weather conditions. Meeting the transportation challenge demands an analytical and a more comprehensive and systematic approach to the management of the risks. More detailed analysis has been made possible through developments in computing and modeling technology. That technology plays an essential role in addressing the key safety issues associated with emerging LNG transportation needs in the Arctic trade. In addition, the application of risk assessment methodology in the evaluation of novel concepts permits a better understanding of the risks associated with LNG shipping in arctic waters and its integration into design technical standards, survey requirements and operational practices. The paper will discuss various aspects of the ship design and operational requirements from a Classification perspective. Particular consideration will be given to issues such as the strength of the hull structure to endure ice loads on deck, ice breaking capabilities and the design of the containment system to withstand the dynamic loads envisaged under harsh weather conditions, in particular sloshing loads. In addition the paper will cover requirements for safety equipment and systems under freezing condition and the propulsion systems for ships in this trade. The paper will summarize the latest Classification technology initiatives to support the development of standards for the design, construction and maintenance of an LNG carrier operating in a harsh cold weather environment.