US-12618530-B2 - Triple-shell tank

Abstract

A triple shell tank includes an inner tank, an intermediate tank covering the inner tank, and an outer tank covering the intermediate tank. The inner tank includes an inner tank side plate, an inner tank roof, and an inner tank bottom plate. The intermediate tank includes an intermediate tank side plate, an intermediate tank roof, and an intermediate tank bottom plate. The circular steps of the intermediate tank side plate include a lowermost step formed of an intermediate tank side plate piece for height adjustment having a height corresponding to a height difference between the inner tank bottom plate and the intermediate tank bottom plate, and a second step on the lowermost step formed of an intermediate tank side plate piece arranged at a same height position as an inner tank side plate piece of a lowermost step in the circular steps of the inner tank side plate.

Inventors

• Takanori KOMATSU

Assignees

• KAWASAKI JUKOGYO KABUSHIKI KAISHA

Dates

Publication Date

20260505

Application Date

20221220

Priority Date

20211227

Claims (4)

1. 1 . A triple shell tank comprising: an inner tank; an intermediate tank covering the inner tank; and an outer tank covering the intermediate tank, wherein the inner tank includes an inner tank side plate, an inner tank roof, and an inner tank bottom plate, the inner tank side plate being assembled by stacking a plurality of circular steps formed by arranging a plurality of inner tank side plate pieces in a circular ring shape, the intermediate tank includes an intermediate tank side plate, an intermediate tank roof, and an intermediate tank bottom plate, the intermediate tank side plate being assembled by stacking a plurality of circular steps formed by arranging a plurality of intermediate tank side plate pieces in a circular ring shape, and the circular steps of the intermediate tank side plate include a lowermost step formed of an intermediate tank side plate piece for height adjustment having a height corresponding to a height difference between the inner tank bottom plate and the intermediate tank bottom plate, and a second step on the lowermost step formed of an intermediate tank side plate piece arranged at a same height position as an inner tank side plate piece of a lowermost step in the circular steps of the inner tank side plate.
2. 2 . The triple shell tank according to claim 1 , further comprising an inner tank anchor strap having one end connected to the inner tank side plate and another end connected to the lowermost intermediate tank side plate piece.
3. 3 . The triple shell tank according to claim 1 , further comprising an intermediate tank anchor strap having one end connected to the intermediate tank side plate piece in the second step and another end connected to a base structure of the triple shell tank.
4. 4 . The triple shell tank according to claim 2 , further comprising an intermediate tank anchor strap having one end connected to the intermediate tank side plate piece in the second step and another end connected to a base structure of the triple shell tank.

Description

TECHNICAL FIELD The present disclosure relates to a triple shell tank that stores a low temperature liquefied gas. BACKGROUND ART A flat-bottomed tank having a multi-shell structure is known as a facility for storing a low temperature liquefied gas. Patent Literature 1 discloses a flat-bottomed tank having a triple shell structure including an inner tank, an intermediate tank, and an outer tank. In construction of the triple shell tank, it is desirable from the viewpoint of shortening the construction period not to sequentially install the inner tank, the intermediate tank, and the outer tank but to construct them in parallel. In this case, construction openings for carrying in and out construction materials and construction equipment and for allowing workers to enter and exit are opened on the side plate of each of the inner tank, the intermediate tank, and the outer tank. In general, the side plate of each of the inner tank, the intermediate tank, and the outer tank is assembled by stacking a plurality of circular steps formed by arranging side plate pieces in a circular ring shape. The construction opening is opened by temporarily removing one or a plurality of the side plate pieces after the circular step is formed. The triple shell tank has a structure in which the intermediate tank covers the entire inner tank, and the outer tank covers the entire intermediate tank. A cool layer is interposed between the bottom plates of adjacent tanks, and therefore a height difference occurs between the height positions of the bottom plates of each tank. Therefore, a height difference also occurs at the lowermost height position of the side plate of each tank. Accordingly, when the construction opening is opened on each side plate by removing the side plate piece, a step may occur between adjacent construction openings. This step may interrupt smooth work implementation. CITATION LIST Patent Literature Patent Literature 1: JP S55-20937 A SUMMARY OF INVENTION An object of the present disclosure is to provide a structure excellent in workability during construction in a triple shell tank including an inner tank, an intermediate tank, and an outer tank. A triple shell tank according to one aspect of the present disclosure is a triple shell tank including: an inner tank; an intermediate tank covering the inner tank; and an outer tank covering the intermediate tank, in which the inner tank includes an inner tank side plate assembled by stacking a plurality of circular steps formed by arranging a plurality of inner tank side plate pieces in a circular ring shape, an inner tank roof, and an inner tank bottom plate, the intermediate tank includes an intermediate tank side plate assembled by stacking a plurality of circular steps formed by arranging a plurality of intermediate tank side plate pieces in a circular ring shape, an intermediate tank roof, and an intermediate tank bottom plate, and the circular steps of the intermediate tank side plate include a lowermost step formed of an intermediate tank side plate piece for height adjustment having a height corresponding to a height difference between the inner tank bottom plate and the intermediate tank bottom plate, and a second step on the lowermost step formed of an intermediate tank side plate piece arranged at a same height position as an inner tank side plate piece of a lowermost step in the circular steps of the inner tank side plate. According to the present disclosure, it is possible to provide a structure excellent in workability during construction in a triple shell tank including an inner tank, an intermediate tank, and an outer tank. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a longitudinal cross-sectional view illustrating an example of a triple shell tank of the present disclosure. FIG. 2 is a cross-sectional view illustrating details of the vicinity of a lower end of a side plate of each tank of the triple shell tank. FIG. 3 is an exploded view illustrating a stack state of a circular step formed by a side plate piece for each of an inner tank side plate, an intermediate tank side plate, and an outer tank side plate. FIG. 4 is a cross-sectional view illustrating an open state of a construction opening of an inner tank side plate, an intermediate tank side plate, and an outer tank side plate. FIG. 5 is a cross-sectional view illustrating a placement state of an inner tank anchor strap and an intermediate tank anchor strap. DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of the triple shell tank according to the present disclosure will be described in detail with reference to the drawings. The triple shell tank that is a construction target of the present disclosure is a tank that stores a low temperature liquefied gas, and is a flat-bottomed tank having a ground installation triple shell structure. The liquefied gas to be stored is, for example, liquefied hydrogen or liquid helium. [Structure of Triple Containment Tank] The structure of a triple shell tank