LEAK PREVENTIVE METHOD FOR LIQUEFIED FUEL PIPE FLANGE

摘要

PURPOSE:To prevent leakage of liquefied fuel, by externally cooling the flange of fuel pipe, so that the temperature difference between the flange and the bolt center at the time of pipe cool-down. CONSTITUTION:A detailed study of relationships between packing, face pressure and cooling speed of a flange coupling used for LNG piping has led to a conclusion that the leakage from the flange coupling at the time of cool-down is attributable to a temperature difference between the flange and bolts used for fastening the flange, in other words, a change in the flange, packings and their face pressure. The temperature of the flange and the center of the bolt is observed and then the flange is so cooled that the allowable temperature difference is about half that for generating the leakage. This control method of differential temperature is practicable for preventing the leakage from the flange.