| 摘要 |
PURPOSE:To make an independent breeding tank unnecessary,by providing such an arrangement that an outer tank is formed in a two unit structure consisting of a floating roof and an outer tank body, and the floating roof is elevated in accordance with variations in the pressure differential between the inner and outer tanks. CONSTITUTION:An inner tank 1 which is set on a heat-insulator 4 is disposed in an outer tank comprising an outer tank body 2 and a floating roof 3 which is elevatably fitted onto the outer tank body 2 to cover the inner tank 1. Pedestals 5 are attached to the inner wall of the outer tank body 2 in predetermined positions to support the floating roof 3, and further, stoppers 7 are projectingly formed on the inner wall of the floating roof 3 below an outer surface receiving member 6 to prevent the floating roof 3 from raising above a predetermined level. A seal bag 8 is attached along the entire periphery of the floating roof 3 below the stoppers 7 to air-tightly seal between the outer tank body 2 and the floating roof 3. |
