Large double-layer low-temperature ethylene storage tank

Abstract

The large double-layer low-temperature ethylene storage tank comprises a tank body, the tank body is composed of an inner tank and an outer tank, a hot corner protection layer bottom plate is arranged between bottom plates of the inner tank and the outer tank, a middle-layer wall plate is welded to the lower portion of the inner side wall of the outer tank, the upper end of the middle-layer wall plate is welded to the inner side wall of the outer tank, and the lower end of the middle-layer wall plate is welded to the lower portion of the inner side wall of the outer tank. The lower end of the middle layer wall plate is in arc transition welding with the hot corner protection layer bottom plate, and a reinforcing base plate is welded to a welding seam at the arc welding position. Compared with the prior art, right-angle welding of the middle layer wall plate and the hot corner protection layer bottom plate is changed into bending steel plate butt joint, smooth transition butt joint type welding is achieved, steel plate deformation caused by thermal expansion of the tank body can be effectively absorbed, welding seam cracking is prevented, and the independent staircase design is adopted, so that the welding efficiency is improved. The additional load of the wall plate of the tank body can be effectively reduced, the wall thickness of the tank body and the size design of the foundation can be reduced, and later overhaul and maintenance from stairs are facilitated.

Description

Technical Field

[0001] The utility model relates to the field of petrochemical industry, and in particular to a large double-layer low-temperature ethylene storage tank. Background Art

[0002] At present, in the petrochemical field, the common ethylene storage tanks are small in diameter and height, and the volume is not large. Conventional design can meet the design requirements. However, some large ethylene storage tanks have an inner tank size of φ42X35.8m and an outer tank size of φ44X39m, with a capacity of 46000m 3 The operating temperature reaches -104°. Due to the large size and total weight of the storage tank, the structural design must be optimized to ensure the absolute safety and reliability of the equipment operation.

[0003] Because leaked low-temperature ethylene is flammable and explosive, ethylene tank failures often occur due to cracking in the welds between the tank's bottom plate and siding. Conventional thermal angle protection layers are added between the outer and inner tanks, with the bottom plate and siding also using fillet welds. This design changes the fillet weld between the siding and bottom plates to a butt weld with a curvature of R200. This replaces one fillet weld with two butt welds, adding a backing plate to the outside of the weld to ensure full penetration. Advantages: The connection structure between the intermediate siding and bottom plates is changed from a fillet weld to an R200 smooth transition butt weld, which effectively absorbs steel plate deformation caused by thermal expansion of the tank and prevents weld cracking.

[0004] Common ethylene storage tanks have small diameters and heights, resulting in small volumes, low total weight, and minimal settlement. Conventional designs utilize spiral staircases leading from the ground to the top, bolted or welded to the tank's exterior. If large ethylene storage tanks still utilize spiral staircases fixed to the tank's exterior, the additional load on the cladding is significant, requiring higher cladding thickness. This can easily lead to heavier tanks and significant foundation settlement. Utility Model Content

[0005] The purpose of this utility model is to provide a large double-layer low-temperature ethylene storage tank that solves the above problems.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a large double-layer low-temperature ethylene storage tank, including a tank body, which is composed of an inner tank and an outer tank, and a thermal angle protection layer bottom plate is provided between the bottom plates of the inner tank and the outer tank, and an intermediate layer wall panel is welded to the lower part of the inner wall of the outer tank, and the upper end of the intermediate layer wall panel is welded to the inner wall of the outer tank, and the lower end of the intermediate layer wall panel is welded to the thermal angle protection layer bottom plate in an arc transition, and a reinforcing pad is welded on the weld at the arc welding position.

[0007] Preferably, an arc-shaped connecting transition plate is provided between the intermediate layer wall panel and the thermal corner protection layer bottom plate, and the upper and lower ends of the connecting transition plate are welded to the intermediate layer wall panel and the thermal corner protection layer bottom plate respectively.

[0008] Preferably, the connecting transition plate is a curved steel plate with a curvature of R200.

[0009] Preferably, the reinforcing pad is arc-shaped and is connected to the outer side of the connecting transition plate, and the arc length of the reinforcing pad is greater than that of the connecting transition plate.

[0010] Preferably, the space between the wall panels of the inner tank and the outer tank is filled with expanded perlite.

[0011] Preferably, insulation bricks are filled between the intermediate layer wall panels and the wall panels of the outer tank.

[0012] Preferably, a bottom insulation layer is filled between the bottom plate of the inner tank and the bottom plate of the thermal corner protection layer, and insulation bricks are filled between the bottom plate of the outer tank and the bottom plate of the thermal corner protection layer.

[0013] Preferably, an inspection platform is provided on the top of the tank body, an independent staircase is provided on the side of the tank body, a walkway is provided between the inspection platform and the top of the staircase, and the staircase is connected to the inspection platform through the walkway.

[0014] Preferably, oblong bolt holes are vertically opened on the end plates at both ends of the walkway, and are fixedly connected to the inspection platform and the end surface of the stairs respectively by fastening bolts matching the oblong bolt holes.

[0015] Compared with the prior art, the advantages of the present invention are:

[0016] (1) The utility model changes the right-angle welding between the intermediate layer wall plate and the bottom plate of the thermal angle protection layer into butt welding of steel plates with a curvature of R200, and changes one corner weld into two butt welds, thus realizing a smooth transition butt welding type. It can effectively absorb the deformation of the steel plate caused by thermal expansion of the tank body and prevent the weld from cracking. In addition, a reinforcing pad is welded outside the butt weld to use the reinforcing pad as a reinforcing rib to ensure full penetration of the weld.

[0017] (2) The utility model designs and installs the tank body and the stairs on independent foundations. After reaching the top via the stairs, the stairs are connected to the inspection platform via a walkway, eliminating the need for the stairs to be fixed to the tank body. This effectively reduces the additional load on the tank body wall, and can reduce the tank body wall thickness and the size of the foundation design. Since ethylene gas is prone to combustion or explosion when exposed to high temperatures or fire sources, the stairs are designed to be independent and at a certain distance from the tank body, making it convenient for later inspection and maintenance from the stairs.

[0018] (3) Due to the heavy weight of the tank body and the significant foundation settlement, the two ends of the walkway are connected to the tank body and the stairs respectively with vertical oblong bolt holes, which can effectively eliminate the displacement between the tank body and the stairs caused by foundation settlement. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0020] Figure 2 This is a schematic diagram of the assembly of the walkway and maintenance platform of the utility model;

[0021] Figure 3 It is a partial schematic diagram of the interior of the tank body of the utility model.

[0022] In the figure, 1. tank body; 2. walkway; 3. stairs; 4. maintenance platform; 5. oblong bolt hole; 6. middle layer wall panel; 7. bottom insulation layer; 8. thermal corner protection layer bottom plate; 9. connection transition plate; 10. reinforcement pad; 11. outer tank; 12. inner tank; 13. expanded perlite; 14. insulation brick. DETAILED DESCRIPTION

[0023] The utility model will be further described below.

[0024] A large double-layer low-temperature ethylene storage tank includes a tank body 1, which is composed of an inner tank 12 and an outer tank 11. Figure 3 A thermal angle protection layer bottom plate 8 is provided between the bottom plates of the inner tank 12 and the outer tank 11. An intermediate layer wall plate 6 is welded to the lower portion of the inner side wall of the outer tank 11. The upper end of the intermediate layer wall plate 6 is welded to the inner side wall of the outer tank 11. The lower end of the intermediate layer wall plate 6 is welded to the thermal angle protection layer bottom plate 8 in an arc transition, and a reinforcing pad 10 is welded to the weld at the arc weld. The present invention replaces the right-angle welding of the intermediate layer wall plate 6 and the thermal angle protection layer bottom plate 8 with a butt weld of steel plates with a curvature of R200. One fillet weld is replaced with two butt welds, achieving a smooth transition butt weld type. This can effectively absorb the deformation of the steel plates caused by thermal expansion of the tank body 1 and prevent weld cracking. In addition, a reinforcing pad 10 is welded outside the butt weld to use as a reinforcing rib to ensure full penetration of the weld.

[0025] An arc-shaped connecting transition plate 9 is provided between the intermediate layer wall panel 6 and the thermal corner protection layer bottom plate 8. The upper and lower ends of the connecting transition plate 9 are respectively welded to the intermediate layer wall panel 6 and the thermal corner protection layer bottom plate 8. The arc transition between the intermediate layer wall panel 6 and the thermal corner protection layer bottom plate 9 is realized through the connecting transition plate 9. The connecting transition plate 9 is an arc-shaped steel plate with a curvature of R200.

[0026] The reinforcing pad 10 is arc-shaped and is circumscribed to the outer side of the connecting transition plate 9. The arc length of the reinforcing pad 10 is greater than that of the connecting transition plate 9, and the two butt welds can be effectively reinforced.

[0027] The space between the inner tank 12 and the outer tank 11 is filled with expanded perlite 13, which has a good thermal insulation effect. The space between the intermediate layer wall 6 and the outer tank 11 is filled with insulation bricks 14, which play a role in thermal insulation and supporting the intermediate layer wall 6.

[0028] A bottom insulation layer 7 is filled between the bottom plate of the inner tank 12 and the bottom plate 8 of the thermal corner protection layer, and the bottom insulation layer 7 plays a role of insulation. Insulation bricks 14 are filled between the bottom plate of the outer tank 11 and the bottom plate 8 of the thermal corner protection layer, and the insulation bricks 14 play a role of insulation and support.

[0029] An inspection platform 4 is provided on the top of the tank body 1, and an independent staircase 3 is provided on the side of the tank body 1. A walkway 2 is provided between the inspection platform 4 and the top of the staircase 3, and the staircase 3 is connected to the inspection platform 4 through the walkway 2. Figure 1 This utility model designs and installs the tank body 1 and staircase 3 on independent foundations. After reaching the top via the staircase 3, the walkway 2 connects to the inspection platform 4, eliminating the need for the staircase 3 to be fixed to the tank body 1. This effectively reduces the additional load on the tank body 1 wall panels, allowing for a smaller wall thickness and foundation design. Because ethylene gas is prone to combustion or explosion when exposed to high temperatures or fire, the staircase 3 is designed to be independent and at a distance from the tank body 1, facilitating later inspection and maintenance from the staircase 3.

[0030] In addition, due to the heavy weight of the tank body 1 and the significant foundation settlement, the two ends of the walkway 2 are connected to the tank body 1 and the stairs 3 respectively using vertical oblong bolt holes 5, which can effectively eliminate the displacement between the tank body 1 and the stairs 3 caused by the foundation settlement. Therefore, oblong bolt holes 5 of M20X55 are used on the end plates at both ends of the walkway 2, and are fixed to the maintenance platform 4 and the end surface of the stairs 3 respectively through fastening bolts matching the oblong bolt holes 5. Figure 2 .

[0031] The above is a detailed introduction to a large double-layer low-temperature ethylene storage tank and process provided by the utility model. Specific examples are used in this article to illustrate the principles and implementation methods of the utility model. The description of the above embodiments is only used to help understand the method and core idea of ​​the utility model; at the same time, for those skilled in the art, according to the idea of ​​the utility model, there will be changes in the specific implementation method and application scope. Changes and improvements to the utility model will be possible without exceeding the concept and scope specified in the appended claims. In summary, the content of this specification should not be understood as a limitation on the utility model.

Claims

1. A large double-layer low-temperature ethylene storage tank, comprising a tank body, characterized in that: The tank body consists of an inner tank and an outer tank, a thermal angle protection layer bottom plate is provided between the bottom plates of the inner tank and the outer tank, an intermediate layer wall plate is welded to the lower part of the inner wall of the outer tank, the upper end of the intermediate layer wall plate is welded to the inner wall of the outer tank, the lower end of the intermediate layer wall plate is welded to the thermal angle protection layer bottom plate in an arc transition, and a reinforcing pad is welded to the weld at the arc welding location.

2. A large double-layer low-temperature ethylene storage tank according to claim 1, characterized in that: An arc-shaped connecting transition plate is provided between the intermediate layer wall plate and the thermal corner protection layer bottom plate, and the upper and lower ends of the connecting transition plate are respectively welded to the intermediate layer wall plate and the thermal corner protection layer bottom plate.

3. A large double-layer low-temperature ethylene storage tank according to claim 2, characterized in that: The connecting transition plate is a curved steel plate with a curvature of R200mm.

4. A large double-layer low-temperature ethylene storage tank according to claim 2, characterized in that: The reinforcing pad is arc-shaped and is circumscribed to the outer side of the connecting transition plate. The arc length of the reinforcing pad is greater than that of the connecting transition plate.

5. A large double-layer low-temperature ethylene storage tank according to claim 1, characterized in that: The space between the wall plates of the inner tank and the outer tank is filled with expanded perlite.

6. A large double-layer low-temperature ethylene storage tank according to claim 1, characterized in that: The space between the intermediate layer wall plate and the wall plate of the outer tank is filled with thermal insulation bricks.

7. A large double-layer low-temperature ethylene storage tank according to claim 1, characterized in that: A bottom insulation layer is filled between the bottom plate of the inner tank and the bottom plate of the thermal corner protection layer, and insulation bricks are filled between the bottom plate of the outer tank and the bottom plate of the thermal corner protection layer.

8. The large double-layer low-temperature ethylene storage tank according to claim 1, characterized in that: An inspection platform is provided on the top of the tank body, an independent staircase is provided on the side of the tank body, a walkway is provided between the inspection platform and the top of the staircase, and the staircase is connected to the inspection platform through the walkway.

9. A large double-layer low-temperature ethylene storage tank according to claim 8, characterized in that: The end plates at both ends of the walkway are vertically provided with oblong bolt holes, and are fixedly connected to the inspection platform and the end faces of the stairs respectively through fastening bolts matching the oblong bolt holes.

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