JPH108740A - Tank dismantling method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a tank dismantling method capable of shortening the construction period and reducing the construction cost by eliminating the need for long-time high-place work and temporary installation of a large-scale work scaffold. SOLUTION: The lower end of a tank side plate 2a is cut off from a tank bottom 3a and jacked up, and a plurality of wedge-shaped guide members 8 are arranged in a gap generated between the bottom 3a and the lower end of the side plate 2a and fixed to the bottom 3a. An initial state for jacking down the side plate 2a on each guide member 8 and starting dismantling work is prepared, and a plurality of circumferential portions at the lower end of the side plate 2a are vertically cut to a required length, and the cut side plate is cut. While the cut pieces 9 at the lower end 2a are guided by the respective guide members 8, they are expanded in a petal shape by the tank load, the side plate 2a is lowered, and the cut pieces 9 are cut and removed to return to the initial state. Most of 2a is dismantled and the tank roof 4a descending to the bottom 3a is dismantled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to petroleum, LPG, L
The present invention relates to a tank dismantling method for storing NG or the like.

[0002]

2. Description of the Related Art When rebuilding or removing a large tank for storing petroleum, LPG, LNG or the like, it is necessary to disassemble the tank into a size that can be transported by loading it on a truck or the like. .

Conventionally, when such a tank is dismantled, a large-scale work scaffold is temporarily provided around the tank, and by using the work scaffold, an operator sequentially uses a burner to sequentially increase the size of the tank from the upper structure of the tank. , And the work of hanging it on the ground with a large crane was repeated.

[0004]

However, in such a conventional dismantling method, work in a high place where workability is poor is required for a long time, and much time is required for temporarily setting a work scaffold. Therefore, there is a problem that the construction period becomes longer and the construction cost increases.

The present invention has been made in view of the above circumstances, and provides a tank dismantling method capable of shortening the construction period and reducing the construction cost by eliminating the need for long-time high-place work and temporary installation of a large-scale work scaffold. It is intended to be.

[0006]

According to the present invention, the lower end of the tank side plate is separated from the bottom of the tank and jacked up, and the gap formed between the bottom of the tank and the lower end of the tank side plate rises toward the radial center of the side plate. A plurality of wedge-shaped guide members forming a gradient are arranged and fixed to the bottom of the tank, and the tank side plate is jacked down on each of the guide members to prepare an initial state for starting dismantling work. A plurality of locations in the circumferential direction are vertically cut to a required length, and the cut pieces at the lower end of the tank side plate are spread in a petal shape by the tank load while guiding each cut piece to each guide member, and the tank side plate is lowered. Repeating the work of cutting and removing each cut petal-shaped piece and returning to the initial state, after that, most of the tank side plates are dismantled and descend to the tank bottom. Tank demolition method which is characterized in that the dismantling of the tank roof, it relates to a.

In this way, most of the demolition work can be performed on the ground, so that it is not necessary to perform a long-time high-altitude work or a large-scale temporary work scaffold as in the conventional art.

In addition, the dismantling work of the tank roof, which has been conventionally performed at a high place where workability is poor, can be performed on the ground.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 9 show an embodiment of the present invention. In this embodiment, an inner tank 1a and an outer tank 1 are shown.
b illustrates a case in which a ground-type tank 1 having a double shell structure composed of b is dismantled.

The body of each of the inner tank 1a and the outer tank 1b is formed in a cylindrical shape by tank side plates 2a and 2b. The tank side plate 2a of the inner tank 1a is erected on the tank bottom 3a, and the outer tank 1b The tank side plate 2b is erected on the base slab 3b, and dome-shaped tank roofs 4a, 4b are joined to the upper ends of the tank side plates 2a, 2b.

When disassembling the tank 1 having such a double shell structure, first, the storage liquid and the vaporized gas in the tank 1 are extracted and made empty, and then the inner tank 1a and the outer tank 1b are removed.
The suction material such as perlite filled in between is sucked and discharged by a vacuum method. After that, the atmosphere in the tank 1 is replaced with air, and the internal accessories (liquid level gauge, thermometer, Nozzle).

When the dismantling preparation is completed as described above, FIG.
As shown in FIG. 2, the tank roofs 4a and 4b of the inner tank 1a and the outer tank 1b are integrally connected to each other by the support 5, and then the lower end of the tank side plate 2b of the outer tank 1b is cut as shown in FIG. So that all the load of the outer tub 1b is applied to the tank roof 4a of the inner tub 1a.

Further, as shown in FIG. 3, at a plurality of circumferential positions on the outer peripheral surface on the lower end side of the tank side plate 2a of the inner tank 1a,
Attach the support portion 6 that protrudes outward by welding, etc.
A jack 7 such as a screw jack or a hydraulic jack is arranged below each of the support portions 6.

Next, as shown in FIG. 4, the lower end of the tank side plate 2a of the inner tank 1a is separated from the tank bottom 3a, and the inner tank 1a and the outer tank 1 are separated by the jacks 7 through the support portions 6.
b), and further, as shown in FIG. 5, a wedge shape which forms an ascending gradient toward the radial center side of the tank side plate 2a in a gap formed between the tank bottom 3a and the lower end of the tank side plate 2a of the inner tank 1a. A plurality of guide members 8 are arranged and fixed to the tank bottom portion 3a, and as shown in FIG. 6, the tank side plate 2a of the inner tank 1a is jacked down on each guide member 8, and each jack 7 and each support portion 6 are formed. Remove and prepare the initial state to start dismantling work.

After preparing the initial state in this way, as shown in FIG. 7, a plurality of circumferential portions at the lower end of the tank side plate 2a of the inner tank 1a are cut in a required length in the vertical direction, and the cut tank side plate 2a is cut. While the cut pieces 9 at the lower end are guided by the guide members 8, the cut pieces 9 are spread in a petal shape by the tank load, and the tank side plate 2 a is lowered. Then, as shown in FIG. Thereafter, the operation returns to the initial state, and thereafter, the above-described operation procedure from the initial state is repeated in the same manner to continue the disassembly operation.

At this time, as the tank side plate 2a of the inner tank 1a is lowered, the tank side plate 2b of the outer tank 1b is also lowered, so that the lower end of the tank side plate 2b of the outer tank 1b is cut and removed in accordance with the lowered state of the tank 1. And the tank side plate 2a of the inner tank 1a
Of course, it does not hinder the cutting operation for the lower end.

The tank load decreases as the tank side plates 2a and 2b are dismantled.
Generally, the thickness of each of the tank side plates 2a and 2b is reduced toward the upper side, so that even when the disassembling operation of each of the tank side plates 2a and 2b proceeds, each cut piece 9 can be satisfactorily moved by the tank load. When the entire load of the outer tub 1b is applied to the tank roof 4a of the inner tub 1a as in the present embodiment, a tank load sufficient to spread the cut pieces 9 can be obtained. Can be easily secured.

In this manner, the tank side plates 2a, 2b
As shown in FIG. 9, when the disassembly is advanced from the lower end,
Since most of the tank side plates 2a and 2b are dismantled and the respective tank roofs 4a and 4b are lowered to the tank bottom 3a, the tank roofs 4a and 4b lowered to the tank bottom 3a are used for ground work. The dismantling of the tank 1 is completed by dismantling the tank roofs 4a and 4b.

Therefore, according to the above embodiment, most of the dismantling work can be performed on the ground, so that it is not necessary to perform a long-time work at a high place or temporarily construct a large-scale work scaffold as in the related art. Accordingly, it is possible to shorten the construction period and reduce the construction cost.

In addition, since the tank roofs 4a and 4b can be dismantled on the ground, which has been conventionally performed at a high place where workability is poor, the tank roofs 4a and 4b can be dismantled efficiently and safely. can do.

Incidentally, the tank dismantling method of the present invention is not limited to the above-described embodiment, and the case of a tank having a double shell structure is illustrated in the drawings. It is also possible to apply, in this case,
It is needless to say that the weight may be mounted on the tank roof as needed, and that various changes may be made without departing from the spirit of the present invention.

[0023]

According to the tank dismantling method of the present invention described above, various excellent effects as described below can be obtained.

(I) Since most of the dismantling work can be performed on the ground, it is not necessary to perform long-time high-place work or temporary installation of a large-scale work scaffold as in the conventional art, thereby shortening the construction period. And reduction of construction cost.

(II) Since the tank roof can be dismantled on the ground, which has been conventionally performed at a high place where workability is poor, the tank roof can be dismantled efficiently and safely.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a state in which tank roofs of an inner tank and an outer tank are integrally connected.

FIG. 2 is a schematic view showing a state in which a lower end portion of a tank side plate of an outer tank is cut and removed.

FIG. 3 is a schematic view showing a state where a jack is arranged around a lower end of a tank side plate of an inner tank.

FIG. 4 is a schematic view showing a state in which a tank side plate of an inner tank is separated from a tank bottom and jacked up.

FIG. 5 is a schematic view showing a state in which a wedge-shaped guide member is arranged between a tank bottom and a tank side plate of an inner tank.

FIG. 6 is a schematic diagram showing a state in which a tank side plate of an inner tank is jacked down on a guide member.

FIG. 7 is a schematic diagram showing a state in which a plurality of locations at the lower end of the tank side plate of the inner tank are cut in the vertical direction and expanded in a petal shape.

FIG. 8 is a schematic diagram showing a state in which each cut piece that has spread in a petal shape is cut and removed and returned to an initial state.

FIG. 9 is a schematic diagram showing a state in which each tank side plate is disassembled and each tank roof is lowered to the tank bottom.

[Explanation of symbols]

 Reference Signs List 1 tank 2a tank side plate 3a tank bottom 4a tank roof 8 guide member 9 cut piece

Claims (1)

[Claims] 1. A wedge-shaped guide member in which a lower end of a tank side plate is separated from a tank bottom portion and jacked up, and a clearance formed between the tank bottom portion and the lower end of the tank side plate forms an upward gradient toward a radially center side of the tank side plate. Are arranged and fixed to the tank bottom, and the tank side plate is jacked down on each of the guide members to prepare an initial state for starting dismantling work. Direction, cut the cut pieces at the lower end of the tank side plate into the petals while guiding each cut piece to each guide member, descend the tank side plate, and then cut each petal-shaped cut The work of cutting and removing the pieces and returning to the initial state was repeated, and after that, the tank roof that descended to the bottom of the tank was dismantled because most of the tank side plates were dismantled. Tank dismantling method characterized by the following.