| 摘要 |
<p>PURPOSE:To prevent a heat transfer pipe from destruction, by generating a solidified nucleus in plural places so as to cause freezing expansion in multiple stages and disperse expansion force when heat source fluid in the heat transfer pipe freezes. CONSTITUTION:A vaporizer, arranging a heat transfer pipe 2 penetrating in an enclosed vessel 1 containing an intermediate medium of Freon or the like, vaporized liquefied natural gas by the intermediate medium. Heat source fluid of the seawater or the like is allowed to flow in said heat transfer pipe 2. And the heat transfer pipe 2, forming in its intermediate part an internal contour reduced part 7-1, 7-2, 7-3 at least in one part, increases a solidified nucleus by said internal contour reduced part 7-1, 7-2, 7-3 when the heat source fluid is allowed to flow staying and freezing.</p> |
