| 摘要 |
PURPOSE:To significantly improve the expansion efficiency of a membrane expansion structure of a low temperature liquefied gas tank by constituting same such that it has, at each fin concentrating section thereof, a plateau formed to swell upwardly from adjacent flat plate sections with each fin being formed continuously from the fin concentrating section to extend divergently from the concentrating section. CONSTITUTION:A low temperature liquefied gas tank, for example an underground low temperature tank, includes, as an outer tank, a body 1 of concrete installed in the foundation 2 and, as an inner tank, a membrane 4 received in the concrete body 1 with suitable heat insulating materials 3 interposed therebetween. In this case, the membrane 4 is constituted as a membrane 10 which has fins 11 disposed to extend in radial directions to make a pattern as of a tortoise shell with each fin 11 extending divergently from a three-forked fin concentrating section 12. As seen in an enlarged view, each fin concentrating section 12 has, at the center thereof, a substantially triangular plateau A formed to swell upwardly from adjacent flat plate sections B, C, D with each fin 11 being formed continuously from the plateau A to make a branch of the three-fork. |
