JP2000046299A - Bottom part cold reserving layer for double barrel low temperature tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent movement of a horizontal direction such as earthquake, and aim at stabilization by arranging a projection/recessed shaped fitting part on upper and lower contact surfaces of a mold body so as to converge movement of the horizontal direction to a ring part cold reserving layer composed of a mold body of a laminated structure arranged on a lower part of an inner tank side plate lower part. SOLUTION: A ring part cold reserving layer 8 arranged on a lower part of an inner tank annular plate 12 just under an inner tank side plate 9, is formed by laminating mold bodies 16 which are mold-manufactured by perlite concrete and the like in a factory and the like beforehand. A fitting part 19 composed of a recessed part 17 and a projection part 18 which are fitted mutually to surfaces that are brought into contact with upper and lower parts at the time of laminating, is arranged on the mold body 16. In a lowest layer mold body 16A made of perlite concrete which is executed at a job site, ensures predetermined compression strength, and can be tightly fixed so as to suppress movement by a fixing member 15. It is thus possible to hold a stable load supporting condition without moving a ring part cold reserving layer in a horizontal direction by the earthquake.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat bottom cylindrical double-shell low-temperature storage tank for storing low-temperature liquefied gas such as liquefied natural gas (LNG) and liquefied propane gas between the inner tank bottom plate and the outer tank bottom plate. It relates to the bottom cold insulation layer to be provided.

[0002]

2. Description of the Related Art The entire structure of a conventional flat-bottom cylindrical double-shell low-temperature storage tank and the structure of a bottom cold-storage layer will be described with reference to FIGS.

As shown in FIG. 7, a flat-bottom cylindrical double-shell low-temperature storage tank has a metal inner tank 1 for storing low-temperature liquefied gas such as liquefied natural gas (LNG), and a cooling layer 3 disposed around the inner tank 1. This is a storage tank having a double shell structure including a metal outer tank 2 provided therebetween. A bottom cooling layer 4 is provided between the inner tank bottom plate 5 and the outer tank bottom plate 6 below the double shell storage tank, that is, on the outer tank bottom plate 6 located below the inner tank bottom plate 5. The bottom cold insulating layer 4 includes a disc-shaped central cold insulating layer 7 and an annular ring cold insulating layer 80 located on the outer periphery thereof. The outer tub 2 may be formed of a prestressed concrete structure having a liquid storage function or a concrete structure, not shown, in addition to the metal as shown in the figure.

[0004] As shown in an enlarged view in FIG. 8, of the cold insulation layer 4 at the bottom of the double-shell low-temperature storage tank, the ring insulation layer 80 is provided below the inner tank annular plate 12 directly below the inner tank side plate 9. I have. In order to support the storage solution and the large load of the inner tank 1, the ring-shaped cold insulating layer 80 has a laminated structure in which the cold insulating material blocks 14 made of perlite concrete or lightweight aggregate concrete having high compressive strength and heat insulating performance are laminated. Has formed. The lowermost layer of the cold insulator block 14 laminated structure is fixed on the upper surface of the outer tank bottom plate 6 so as not to move by casting the concrete body on site.

Further, between the inner tank side plate 9 and the outer tank side plate 10,
In addition, between the outer peripheral surface of the ring-shaped cold insulating layer 80 and the inner wall surface below the outer tank side wall 10, a side cold insulating layer 11 made of a heat insulating material having high heat insulating performance such as perlite particles is provided. Furthermore, between the lower part of the inner tank center bottom plate 13 and the outer tank bottom plate 6, that is, inside the ring cooling layer 80, a laminated structure using a block body of a material having higher heat insulation performance than the ring cooling layer 80. A central cold insulation layer 7 (not shown) is formed.

[0006]

The ring cold storage layer 80 of the bottom cold storage layer 4 of the double-shell low-temperature storage tank as exemplified in FIGS. Since it supports the large load of the inner tank 1, it is strong against the compressive load in the vertical direction. However, when a large load is applied in the horizontal direction due to an earthquake or the like, the cold insulator block 14 of the laminated structure moves horizontally. Was concerned. In addition, there is a concern that the large load applied to the ring-shaped cold insulating layer 80 in the horizontal direction may cause deformation of the cold insulating material blocks 14 and damage due to friction.

Also, when constructing the storage tank, when placing the inner tank annular plate 12 on the upper part and constructing the inner tank side plate 9, care must be taken not to stably support the upper load and to move horizontally. It was necessary to pay for the construction.

The present invention has been made in view of the above-mentioned problems, and has a double-shell low-temperature storage tank that is stable without moving in the horizontal direction even when it receives a horizontal load due to an earthquake or the like and has excellent construction efficiency. To provide a bottom insulation layer.

[0009]

The bottom cold insulating layer of the double-shell low-temperature storage tank according to the present invention is an inner tank of the double-shell low-temperature storage tank provided between the inner tank bottom plate and the outer tank bottom plate. The ring-shaped cold insulating layer made of a laminated body having a laminated structure provided at the lower part of the side plate is provided with an uneven fitting portion on the upper and lower contact surfaces of the molded body so as to restrain horizontal movement.

[0010] In addition, the bottom cold insulating layer of the double-shell low-temperature storage tank according to the present invention is provided below the inner tank side plate of the bottom cold insulating layer provided between the inner tank bottom plate and the outer tank bottom plate of the double-shell low-temperature storage tank. The ring portion heat insulating layer made of a multilayered molded body has a through hole inserted through each of the laminated mold bodies so as to restrain horizontal movement, and a key block made of a columnar cold insulating material inserted so as to fill the inserted hole. Are provided.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cold storage layer at the bottom of a double-shell low-temperature storage tank according to the present invention will be described in detail with reference to FIGS.

As shown in FIG. 1, a ring cooling layer 8 provided directly below the inner tank side plate 9 and below the inner tank annular plate 12.
Is formed by laminating a mold body 16 previously formed from a pearlite concrete body or the like at a factory or the like. The mold body 16 is provided with a fitting portion 19 composed of a concave portion 17 and a convex portion 18 which are fitted to each other on the upper and lower surfaces that are in contact with each other during lamination, so that even if a horizontal load due to an earthquake or the like is received, , So as not to move in the horizontal direction.

The lowermost layer portion of the ring-shaped cold insulating layer 8 formed by lamination may be formed by fixing a lowermost layer mold body 16A made of perlite concrete or the like in advance at a factory or the like on the outer tank bottom plate. Alternatively, a fixing member 15 such as a shaped steel material previously fixed to the upper surface of the outer tank bottom plate 6 is embedded.
If the perlite concrete is constructed by casting in place, the fixing strength of the mold body 16A is further increased. The lowermost molded body 16A made of perlite concrete that has been constructed in the field has a predetermined compressive strength and a fixed member 1A.
5 can be firmly fixed so as not to move. Above the lowermost mold body 16A, there are provided a concave portion 17A and a convex portion 18A which are fitted in a stacked state.

For the intermediate layer of the ring-shaped cold insulating layer 8 formed by lamination, an intermediate layer molded body 16B made of a material having relatively good heat insulation performance such as perlite concrete is used at a factory or the like. This intermediate layer mold 1
The recesses 17 fitted in the upper and lower portions of 6B in a stacked state are also provided.
B and the projection 18B are provided respectively. The intermediate layer mold body 16B is desirably made of a material having a high heat insulating performance. If the strength is slightly inferior, the intermediate layer mold body 16B may be damaged during transportation or construction by forming a large cross-sectional area of the portion serving as the convex portion 18B. It is possible to enhance the strength at the time of fitting without the need. In the case of FIG.
Although the case where B is a single layer is shown, it may be formed of a plurality of layers in relation to manufacturing, transportation, and arrangement work.

The uppermost layer of the ring-shaped cold insulating layer 8 formed by lamination is made of a material having high compressive strength, such as lightweight aggregate-containing concrete such as mesalite, for directly receiving the inner tank load or the like. An uppermost mold body 16C formed in a factory or the like is used. A concave portion 17C and a convex portion 18C are provided below the uppermost mold body 16C to form a fitting portion 19C.
To form Since the uppermost molded body 16C uses a material having excellent compressive strength, the convex portion 18C formed at the lower portion of the uppermost molded body 16C has high strength, and may be chipped during transportation, construction, or when using a storage tank. There is no damage.

A filling cold insulating material 20 made of a heat insulating material such as perlite concrete is filled between an outer peripheral surface of the ring cold insulating layer 8 and an inner wall surface below the outer tub side plate 10 so as to fill the ring cold insulating layer. 8 Formed so as to restrict movement in the outer peripheral direction. The filling cold insulating material 20 is constructed by using a heat insulating material having adhesiveness and elasticity at the place of casting so as to maintain the close contact with the peripheral wall surface. By applying the filling cold insulating material 20 in this manner, the horizontal movement of the ring cold insulating layer 8 can be prevented, and the ring cold insulating layer 8 can be suppressed to prevent the laminate from collapsing.

FIG. 2 shows an embodiment in which the mold bodies 16 (16A, 16B, 16C) constituting the ring cooling layer 8 are stacked. Fitting portion 1 provided on mold body 16
Numeral 9 (19A, 19B, 19C) shows a case where it is formed by a circular concave portion 17 (17A, 17B, 17C) and a cylindrical convex portion 18 (18A, 18B, 18C) as shown in the figure. By providing the fitting portion 19 for fitting the concave and convex portions formed on the upper and lower contact surfaces of the mold body 16 having the laminated structure as described above, the laminated upper and lower mold bodies are not shifted from each other due to an earthquake or the like, and are not horizontal. A stable state can be maintained without moving in the diametric direction and the circumferential direction. The figure shows a case where one concave portion 17 and one convex portion 18 are provided.
In order to increase the strength in the horizontal direction, a plurality is provided to increase the sectional area of the joint. Alternatively, although not shown, it may be formed of a triangular, rectangular, trapezoidal or other irregular portion that is easy to manufacture and easy to stack.

As illustrated in FIG. 2, on the lower surface of the uppermost mold body 16C formed of concrete or the like using a lightweight aggregate such as mesalite having relatively high compressive strength,
A cylindrical projection 18C is provided in the fitting portion 19C. Even if this convex part 18C has a small cross-sectional area as shown in the figure,
Since the high-strength material is used as described above, there is no chipping or damage during transportation, construction, or use of the storage tank. Further, a cylindrical convex portion 18B provided on an intermediate layer mold body 16B formed of perlite concrete or the like.
As shown in the figure, the fitting portion 19C is formed in a cylindrical shape with a large cross-sectional area so that it is not chipped or damaged during transportation or construction, and the strength at the time of fitting is increased. it can. The recesses 17C and 17B provided in the intermediate layer mold body 16B are formed so as not to be crushed, buried, or damaged. These molds 1
Since 6B and 16C can be manufactured by being poured into a mold in advance at a factory or the like, uniformity can be achieved with good dimensional accuracy and good quality performance. Further, the lowermost mold body 16A is constructed with high work efficiency by using perlite concrete or the like cast in place.

The ring cooling layer 8 illustrated in FIG. 3 includes a fitting portion 29 (29A, 29B, 29C) provided on the mold body 16 (16A, 16B, 16C) and a rectangular recess 27.
(27A, 27B, 27C) and the rectangular projection 28 (28
A, 28B, 28C), and a single unit is provided at the center along the circumferential direction. The mold body 16 provided with such uneven portions has a structure that is resistant to horizontal movement in the diameter direction of the storage tank. Since the rectangular long convex portion 28 has a large cross-sectional area and a large surface area on the top, even if the strength of the heat insulating material of the mold body 16 is small, it does not chip or damage during transportation, It is not damaged because the strength can be increased even when using a storage tank. Further, the long rectangular recess 27 does not have to worry about damage even if the strength of the heat insulating material of the mold body 16 is small because the groove is hard to be crushed. In the illustrated example, a case where a single wide rectangular uneven portion is provided at the center is shown, but in consideration of strength, production, transportation, construction, etc., a narrow rectangular uneven portion is provided. A plurality of portions may be provided in parallel. Alternatively, the concave and convex fitting portions may be formed in a mountain shape and a groove shape such as a hemispherical cross section or a triangular cross section, and a plurality of the fitting portions may be provided in parallel along the circumferential direction or the diametrical direction.

The ring cooling layer 8 shown in FIG. 4 is fitted not only in the fitting section 29 provided along the circumferential direction of the storage tank as shown in FIG. 3 but also in the direction along the diameter of the storage tank. Part 39 (3
9A, 39B, and 39C) are shown. A key frame-shaped convex portion 3 is provided below the uppermost mold body 16C.
8C, and a key-groove-shaped recess 37C is provided above the intermediate layer mold body 16B below it. The fitting portion 39B of the intermediate layer mold body 16B is provided with a key frame-shaped projection 38B and a key groove-shaped recess 37B.
Also, the fitting portion 39A of the lowermost mold body 16A has
A key frame-shaped protrusion 38A and a key groove-shaped 37A are provided. As described above, the molded body 16 provided with the fitting portion 39 having the key structure in the direction along the diametrical direction of the storage tank can also prevent the circumferential movement of the ring portion cold insulating layer 8 in the circumferential direction. Although not shown, the uneven fitting portion is formed in a shape that is easy to manufacture, transport, and construct, and is formed at both ends of the mold body, or in a lattice shape, in different directions of vertical and horizontal positions.
This prevents a side slip at the boundary of each mold body and provides a strong structure. Although not shown, when the mold bodies of the respective layers are sequentially shifted in the circumferential direction and laminated, the restraining force of the rotational movement in the circumferential direction can be further increased.

The ring cooling layer 8 illustrated in FIG. 5 has a mold body 16 (16A, 16B, 16) provided with an insertion hole 21 penetrating at least a plurality of layers from above to below.
C) are laminated, and a key block 22 is inserted so as to fill the insertion hole 21 of the molded body 16, and the molded body 16 is
Are formed so as not to move in the horizontal direction. The key block 22 is made of a material having high horizontal shear strength and compressive strength and good heat insulating properties, such as perlite concrete. The shape of the insertion hole 21 and the key block 22 is a column shape as shown in the figure, a polygonal column shape not shown, a substantially conical shape, a substantially pyramid shape, a wedge shape, or the like, and a shape that is easy to manufacture and construct. In addition, insertion hole 2
The number of 1 and the key block 22 may be plural according to heat insulation and strength, ease of manufacture and construction, horizontal stability, and the like. Since the molded body 16 and the key block 22 provided with the insertion holes 21 can be molded in advance using a mold or the like at a factory or the like, dimensional accuracy and quality performance can be achieved. If a granular cold insulator such as pearlite grains or a heat insulating material having excellent elasticity and cold insulating performance such as glass wool is interposed between the key block 22 and the key block 22 in the insertion hole 21, a gap is hardly generated and a more stable fixing is achieved. And it is possible to maintain the cooling performance.

As shown in FIG. 5, a filling insulating material 30 made of a heat insulating material such as perlite concrete cast on site is provided between the outer peripheral surface of the ring-shaped insulating layer 8 and the inner wall surface below the outer tank side plate 10. Is installed, the key block 2
In addition to preventing the movement of the ring cooling layer 8 due to the shear force of 2, the outer circumferential stability is further increased. In addition, when the filling cold insulating material 30 having adhesiveness and elasticity is applied, adhesion between the ring portion cold insulating layer 8 and the peripheral wall can be obtained, and the collapse of the laminate can be prevented. In addition, the mold 1
When the above-mentioned key block 22 is formed by filling and inserting a heat insulating material such as perlite concrete cast in place into the insertion hole 21 of No. 6, the gap is also filled, so that the adhesion is improved, and the integration of the laminate is improved. Can be further improved.

The ring cooling layer 8 illustrated in FIG. 6 is provided with a plurality of insertion holes 31 and 41 over each layer vertically adjacent to the mold bodies 16A, 16B and 16C.
A plurality of key blocks 3 with different materials and shapes for 1, 41
An embodiment example in which two and 42 are provided and fixed so as not to move in the horizontal direction is shown. Key blocks 32 and 42 are
When the strength is taken into consideration, the heat insulation performance decreases, and when the heat insulation property is taken into account, the strength decreases. Therefore, by dividing into a plurality of parts in consideration of the strength and the heat insulating property, the performance of both can be dispersed and averaged, and balanced strength and heat insulating performance can be secured. As shown in the figure, a key block 32 having heat insulation performance equivalent to that of the mold bodies 16A and 16B is inserted into the insertion hole 31 located in the intermediate layer, and the insertion hole 4 located in the upper layer is formed.
1 shows a case where a key block 42 having a compressive strength and a shear strength equal to or higher than that of the molded body 16C is inserted. Although not shown, for each layer vertically adjacent to each other,
In accordance with the heat insulation performance and compressive strength of each layer, by using multiple key blocks of different materials and shapes, while maintaining the cooling performance and strength of the ring cooling layer,
It is possible to more efficiently increase the resistance between the layers in the horizontal direction.

[0024]

As described above, of the cold insulation layer at the bottom of the double-shelled low-temperature storage tank according to the present invention, the ring insulation layer made of a laminated molded body provided below the inner tank side plate has a horizontal movement. Since the upper and lower contact surfaces of the mold body are provided with uneven fitting portions so as to restrain them, the ring cooling layer does not move horizontally due to an earthquake or the like, and a stable load supporting state is maintained. In addition, since friction is prevented at the laminated contact surface of the mold body and frictional damage is not caused, it is possible to maintain the cool performance of the ring cool layer. In addition, the mold body is easily aligned horizontally at the fitting portion and can be easily stacked and fixed. Further, when constructing a heavy object such as an annular plate or an inner tank side plate on the upper part of the laminated mold bodies, the lower part is stable without shifting or moving, so that a safe operation can be performed on the upper part. In addition, since this mold body can be manufactured in a factory or the like in advance, management such as improvement of processing accuracy and uniformity of quality can be achieved.

[0025] In the cold insulation layer at the bottom of the double-shelled low-temperature storage tank according to the present invention, the ring insulation layer formed of a mold having a laminated structure provided below the inner tank side plate is laminated so as to restrain horizontal movement. Since the insertion holes to be inserted into the respective molded bodies and the key blocks made of the columnar heat insulating material inserted so as to fill the insertion holes are provided, it is possible to maintain a stable load supporting state without horizontal movement due to an earthquake or the like. , And good cooling performance can be maintained without a short heat path. In addition, the positioning and installation of the mold body can be easily performed during the construction of the ring cooling layer, and the key block can be easily and easily installed. In addition, since the mold body and the key block can be easily formed easily by adjusting the dimensions in advance at a factory, uniform processing accuracy and quality can be achieved.

[0026]

[Brief description of the drawings]

FIG. 1 is an explanatory vertical cross-sectional view of a double-shelled low-temperature storage tank according to the present invention, showing a part of a bottom cold-storage layer with a part removed.

FIG. 2 is an explanatory perspective view showing an embodiment of a ring-shaped cold insulating layer of the bottom cold insulating layer.

FIG. 3 is a perspective explanatory view showing an embodiment of a mold body for forming a ring cooling layer.

FIG. 4 is a perspective explanatory view showing another embodiment of a mold body.

FIG. 5 is a perspective explanatory view showing an embodiment of a ring-shaped cold insulating layer formed of a molded body provided with an insertion hole and a key block in the bottom cold insulating layer of the double-shell low-temperature storage tank according to the present invention.

FIG. 6 is an explanatory vertical sectional view showing another embodiment of a ring-shaped cold insulating layer formed by a molded body provided with the insertion hole and the key block.

FIG. 7 is an explanatory vertical cross-sectional view schematically showing a conventional cold-holding structure of a double-shell low-temperature storage tank.

FIG. 8 is an enlarged sectional view of a conventional double-shelled low-temperature storage tank with a part of the bottom cold storage layer partially omitted.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 inner tank 2 outer tank 3 cold insulating layer 4 bottom cold insulating layer 5 inner tank bottom plate 6 outer tank bottom plate 7 central cold insulating layer 8,80 ring cold insulating layer 9 inner tank side plate 10 outer tank side plate 11 side cold insulating layer 12 inner tank annular Plate 13 Inner tank central bottom plate 14 Cold insulator block 15 Fixing member 16, 16A, 16B, 16C Molded body 17, 17A, 17B, 17C Recess 27, 27A, 27B, 27C Recess 37, 37A, 37B, 37C Recess 18, 18A , 18B, 18C convex parts 28, 28A, 28B, 28C convex parts 38, 38A, 38B, 38C convex parts 19, 19A, 19B, 19C fitting parts 29, 29A, 29B, 29C fitting parts 39, 39A, 39B, 39C Fitting part 20, 30 Filling cold insulator 21, 31, 41 Insertion hole 22, 32, 42 Key block

Claims (2)

[Claims] 1. A ring-shaped cold insulating layer formed of a multilayered molded body provided at a lower portion of an inner tank side plate among a bottom cold insulating layer provided between an inner tank bottom plate and an outer tank bottom plate of a double shell low temperature storage tank. Characterized in that the upper and lower contact surfaces of the mold body are provided with uneven fitting portions so as to restrain the movement of the mold body. 2. A ring-shaped cold insulating layer formed of a multilayered molded body provided below the inner tank side plate among the bottom cold insulating layers provided between the inner tank bottom plate and the outer tank bottom plate of the double shell low temperature storage tank. A double-shell low-temperature storage tank, comprising: an insertion hole inserted through each of the laminated mold bodies so as to restrict the movement of the mold; and a key block made of a columnar cold insulator inserted so as to fill the insertion hole. Bottom insulation layer.