JPH062513B2 - How to dismantle the storage tank - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for disassembling a storage tank that stores a fluid such as liquefied natural gas or heavy oil and that is airtightly constructed with the outside.

[Conventional technology]

Side walls and bottom plates of storage tanks that store liquefied natural gas, heavy oil, etc.
From inside due to sludge and water contained in the fluid,
Further, when salt and sulfur contained in the outside air corrode from the outside and the corroded portion cannot be regenerated by repair, it is necessary to dismantle the entire tank.

As shown in FIG. 6 as one of the methods for dismantling the entire storage tank, a work scaffold c is temporarily provided outside the storage tank a near the side wall b of the storage tank a from the ground e to the upper part of the storage tank a. The crawler crane d is arranged in e, the worker uses the work scaffold c to sequentially dismantle from the upper part of the storage tank a to a weight that the crawler crane d can support, and the dismantled pieces are temporarily placed on the ground e by the crawler crane d. Then the dismantling of the storage tank is completed.

[Problems to be solved by the invention]

However, such a conventional disassembling method has the following problems.

(1) Since a high-rise work scaffold is required outside the storage tank, a large amount of cost was required for its temporary construction.

(2) Since a large cargo handling machine such as a crawler crane requires a long period of time until the end of dismantling, a great deal of cost was required.

(3) Since there are many dismantling works in high places, the danger is high and the work efficiency is low.

[Object of the Invention]

The present invention was devised to effectively solve the problems of the conventional method, and provides a method of disassembling a storage tank that enables disassembly on the ground without requiring a work scaffold or a large cargo handling machine. With the goal.

[Means for solving problems]

In order to achieve the above object, the method for disassembling the storage tank of the present invention is
A bottom end of the storage tank is tightly adhered around the bottom end, and a cylindrical sealing material mounting frame whose upper end is located near the inner surface of the side wall of the storage tank is provided inside the storage tank so that it can slide on the inner surface of the side wall of the storage tank. An elastic sealing material that adheres to the entire circumference is attached to the upper end of the sealing material mounting frame, and a required position below the position where the sealing material adheres to the side wall of the storage tank is cut over the entire circumference to form an upper storage tank and a lower storage tank. The storage tank, the compressed air is fed into the storage tank to float the upper portion of the storage tank, the side wall of the lower portion of the storage tank is removed, and then the pressure of the compressed air inside the storage tank is adjusted. Even if the lower end of the upper portion is lowered until it comes into contact with the bottom plate, the side wall of the upper portion of the storage tank is successively removed from the lower side in the same procedure as described above.

〔Example〕

Hereinafter, a method for disassembling a storage tank according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of a method for disassembling a storage tank according to the present invention, FIG. 2 is a top view of an opening, and FIG. 3 is a side view of the storage tank during disassembly.

As shown in FIG. 1, before disassembling, the height of the sealing material mounting frame 4 is slightly higher than the height of the lowermost side plate 2a constituting the side wall 2 of the storage tank 1 and increases upward.
Are arranged close to the inside of the side wall 2. The lower end of the sealing material mounting frame 4 is airtightly welded to the bottom plate 3 of the storage tank 1,
An elastic sealing material 5 having one end slidably attached to the side wall 2 is airtightly attached to the upper portion. A blower 7 is arranged on the roof 6 of the storage tank 1, and an opening 8 provided in the central portion of the roof 6 and a discharge port of the blower 7 are connected by a pipe 9. Around the opening 8, as shown in FIG. 2, the required number (the number required to prevent the storage tank 1 from floating and to stabilize the posture of the storage tank 1 when the storage tank 1 floats) One end of the wire rope 10 (three in the embodiment) is fixed at substantially equal intervals, and the other end is wound around the winding drum 11 with a brake provided on the ground 14 two to three times, and then tensioned to prepare. Complete.

As shown in FIG. 3, the blower 7 sends compressed air from the opening 8 to the inside of the storage tank 1 through the pipe 9 and then cuts the upper end of the lowermost side plate 2a over the entire circumference to form the storage tank. It divides into the upper part 1a and the storage tank lower part 1b. After loosening the wire rope 10 to float the storage tank upper portion 1a, the side plate 2a is cut from the bottom plate 3 and removed, and the storage tank upper portion 1a is changed to the bottom plate 3.
The pressure is lowered while adjusting the pressure inside the storage tank 1 until it abuts on the upper surface, and after the abutment, the wire rope 10 is wound around the winding drum 11 to bring the wire rope 10 into a tensioned state.

The remaining storage tank upper portion 1a is sequentially cut and removed by the same procedure as described above, the side wall 2 is removed, and then the roof 6 and the bottom plate 3 are removed to complete the disassembly of the storage tank 1.

[Modification]

The present invention is not limited to the above embodiments, and the following modifications included in the scope of claims are possible.

FIG. 4 to FIG. 5 are cross-sectional views of the storage tank during disassembly showing a modified example.

As shown in FIG. 4, the blower 7 sends compressed air from the opening 8 to the inside of the storage tank 1 through the pipe 9, and then cuts the entire circumference of the upper end of the lowermost side plate 21 to cut the storage tank upper part. It divides into 1a and the storage tank lower part 1b. After loosening the wire rope 10 and floating the storage tank upper part 1a to form a gap C at the cutting point, and inserting at least three pillows 12 into the gap C at substantially equal intervals,
Stop the compressed air supply and lower the storage tank upper part 1a,
The lower end of the side wall 2 is brought into contact with the upper surface of 12 to fix the storage tank upper portion 1a, leaving the side plate block 21a at the place where the pillow 12 is inserted, and cutting and removing the side plate block 21b at the other place from the bottom plate 3. . And as shown in FIG. 5, the upper part 1 of the storage tank
a is re-floated, the pedestal 13 is provided on the bottom plate 3 and the lower end of the side wall 2, the remaining side plate block 21a is cut and removed, and the storage tank upper portion 1a abuts on the upper surface of the bottom plate 3. The pressure inside the storage tank 1 is adjusted and lowered, and after contact, the wire rope 10 is wound around the winding drum 11 to
Ten is tense.

The remaining storage tank upper portion 1a is sequentially cut and removed by the same procedure as described above, and after the side wall 2 is removed, the roof 6 and the bottom plate 3 are removed to complete the disassembly of the storage tank 1.

As described above, by inserting the pillow and the pedestal into the cut gap, it is possible to enhance the work safety.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and various modifications may be made without departing from the gist of the present invention.

〔The invention's effect〕

As described above, the storage tank disassembling method of the present invention has the following excellent effects.

(1) Since it is not necessary to temporarily install a high-rise work scaffold outside the storage tank, it is possible to reduce costs and shorten the construction period.

(2) Since a large cargo handling machine is not required, the cost can be reduced, and a large work space can be secured to increase the work safety.

(3) Since dismantling work on the ground is possible, work efficiency and work safety are increased.

[Brief description of drawings]

FIG. 1 is a sectional view of a method for disassembling a storage tank according to the present invention, FIG. 2 is a top view of an opening, FIG. 3 is a sectional view of a storage tank during disassembly, and FIGS. 4 to 5 are sectional views showing modified examples. FIG. 6 is a sectional view of the conventional method. 1 is a storage tank, 2 is a side wall, 3 is a bottom plate, 4 is a sealing material mounting frame, 5 is a sealing material, 6 is a roof, 7 is a blower, 8 is an opening, 9 is a pipe, 10 is a wire rope, 11 is a winding Drum, 12 is a pillow, and 13 is a pedestal.

Claims (1)

[Claims] 1. A bottom surface of a storage tank is tightly fixed at its lower end all around, and a cylindrical sealing material mounting frame whose upper end is located near the inner surface of the side wall of the storage tank is provided inside the storage tank, and the inner surface of the side wall of the storage tank is provided. An elastic sealing material that slidably adheres to the entire circumference is attached to the upper end of the sealing material mounting frame, and the required position below the position where the sealing material adheres to the side wall of the storage tank is cut over the entire circumference. The storage tank is divided into a storage tank upper part and a storage tank lower part, and compressed air is supplied to the inside of the storage tank to float the storage tank upper part, and then the side wall of the storage tank lower part is removed, and then the pressure of the compressed air inside the storage tank. The lower side of the upper part of the storage tank is lowered until it comes into contact with the bottom plate while adjusting the above, and then the side wall of the upper part of the storage tank is sequentially removed from the lower side in the same procedure as described above.