Chemical Tankers Constructed with Stainless Steel and Stainless Clad Steel for their Cargo Tanks

NK-classed chemical tankers (232 total) were investigated as to their use of stainless steel and stainless clad steel and the cases of damage found in structures consisting of such materials. As the result of the above investigation, it is found that the use of the above materials has risen because of their superiority on corrosion resistance for wide range of cargoes intended to be carried and the extent of use has been enlarged. In NK's experience, serious damages have not been found in such structures and the structures are deemed to have sufficient integrity for carrying dangerous cargoes. The result of structural analysis of typical chemical tankers shows that the conventional design has sufficient strength for the structures including novel application of such materials to shell structure. Though superiority of the materials to mild steel for corrosion resistance is expected, the cases of damage found show not serious corrosion but frequent occurence, especially caused by contact with sea water. Attention is addressed to corrosion protection and operational procedure considering the above damage cases. Further, the problems on the application to shell structure are considered and serious problems are not evident.