JP7796549B2 - Cutting and disassembly methods - Google Patents

Description

This disclosure relates to cutting methods, dismantling methods, repair methods, and operation methods.

When working with structures, in addition to normal operating tasks, demolition work may be required when removing a structure, and repair work may be required when maintaining a structure.

For example, Patent Document 1 discloses a cutting method in which a structure is turned on its side and then cut to disassemble it into individual elements.

Japanese Patent Application Laid-Open No. 2019-210685

However, with the cutting method disclosed in Patent Document 1, effluent may flow out from the cavity within the structure during cutting work.

The purpose of this disclosure is to provide cutting, dismantling, repair, and operation methods that can suppress spills from structures.

To solve the above problem, the cutting method disclosed herein partitions the cavity within a structure with a sealing material and then cuts the structure.

The repair method disclosed herein also identifies cracks extending from cavities within a structure to the exterior surface of the structure and seals the cracks with a sealant.

The operating method disclosed herein also involves partitioning the cavity within the structure with a sealing material and operating the structure.

The method disclosed herein can suppress runoff from structures.

3 is a flowchart of a cutting method according to the first embodiment of the present disclosure. FIG. 1 is a side view of a structure to be cut according to a first embodiment of the present disclosure. FIG. 1 is a side view of a structure after a partitioning step according to a first embodiment of the present disclosure. FIG. 10 is a side view of a structure after a partitioning step according to a second embodiment of the present disclosure. FIG. 10 is a partial cross-sectional view of the extension portion after spraying of the reinforced resin foam according to the second embodiment of the present disclosure. FIG. 10 is a perspective view of a mining rig after a partitioning step according to a third embodiment of the present disclosure. FIG. 11 is a side view of the vessel after the partitioning process according to the fourth embodiment of the present disclosure has been performed. FIG. 13 is a side view of the wind power generation facility after a partitioning step according to a fifth embodiment of the present disclosure has been performed. 10 is a flowchart of an operating method according to a sixth embodiment of the present disclosure. FIG. 10 is a perspective view of a mining rig after a partitioning process according to a sixth embodiment of the present disclosure has been performed. 10 is a flowchart of a repair method according to a seventh embodiment of the present disclosure. FIG. 13 is a side view of the vessel after a closing step according to a seventh embodiment of the present disclosure has been performed. 1 is a schematic cross-sectional view of a plunger pump according to an embodiment of the present disclosure. 10 is a table showing confirmation results according to an embodiment of the present disclosure.

Each embodiment of the present disclosure will be described below using the drawings. The same or corresponding components will be designated by the same reference numerals throughout the drawings, and common descriptions will be omitted.

First Embodiment
A cutting method according to the first embodiment will be described with reference to FIGS.

(Overall procedure for cutting method)
As shown in FIG. 1, an operator performs a cutting method on a structure 1, including a partitioning step (ST01), a cutting step (ST02), and a disassembling step (ST03).

(Structure configuration)
As shown in FIG. 2, in the cutting method of this embodiment, the structure 1 to be cut stands so as to extend from the bottom of the water upward above the water surface WS.
The structure 1 comprises an extension 11 having a cavity 12 therein.
The cavity 12 contains residue RS such as oil, grease, etc.
The cavity 12 extends from underwater to above the water surface WS.

(Partitioning process)
First, the worker performs ST01.
In performing ST01, the worker partitions the cavity 12 in the structure 1 with a sealing material 13 including a resin foam 131.
3 , in ST01, the worker fills the cavity 12 above the cutting line CUT with resin foam 131 so as to plug the cavity 12. At this time, the worker fills the resin foam 131 so that the resin foam 131 is adhered to the entire periphery of the inner wall 14 of the extension portion 11. The worker also fills the upper and lower parts of the cavity 12 with resin foam 131 so that the resin foam 131 and the inner wall 14 of the extension portion 11 seal off the majority of the cavity 12.
When it is necessary to fill the resin foam 131 in a location in the cavity 12 that is difficult to access from outside the structure 1, the worker may fill the cavity 12 with the resin foam 131 by using an opening OP provided in the extension portion 11. After filling the cavity 12 with the resin foam 131, the opening OP is sealed with a door, a cover, or the like.

The resin foam 131 is a foamed resin containing fine bubbles inside the resin. The foamed resin has a lower specific gravity and is more flexible than a material made of resin alone.
If the resin foam 131 has closed-cell foam, the rate at which the residue RS and water permeate into the resin foam 131 is slow, making it more suitable for this application.

The resin foam 131 may be a thermoplastic resin foam or a thermosetting resin foam, but a thermosetting resin foam that can be applied and hardened at room temperature is more preferable.
In the case of thermosetting resins, workers mix the base resin with the curing agent, then spray the uncured resin containing bubbles or a foaming agent onto the surface to harden it. When the uncured resin hardens, it becomes sponge-like.

The resin foam 131 may be filled in three or more locations, not just two, to more reliably prevent leakage of the residue RS, or it may be filled in only one location if it can prevent leakage of the residue RS.

The worker will confirm in advance through testing etc. that the appropriate thickness of the resin foam 131 is sufficient to prevent leakage of residue RS and water intrusion.

Thermosetting resin foams include, but are not limited to, foams made from urethane resin, phenolic resin, urea resin, epoxy resin, and acrylic resin.

For example, rigid urethane foam can be obtained by mixing a polyisocyanate having two or more isocyanate groups (NCO) and a polyol having two or more hydroxyl groups (OH) together with a catalyst (an amine compound, etc.), a blowing agent (water, fluorocarbon, etc.), a foam stabilizer (silicone oil), etc., and spraying the mixture onto a specified location to simultaneously carry out the foaming reaction and resinification reaction. Rigid urethane foam has a density of ^about 25 to 35 kg/m3 and floats on water.
In addition, the usable temperature range for rigid urethane foam is approximately -70 to 100°C, so it can be used outdoors almost throughout the year.

If it is difficult to seal the cavity 12 in a plug-like shape as shown in Figure 3 due to the low viscosity and easy flow of the uncured resin foam 131, the worker may take measures such as placing a net with an appropriate mesh size or a cloth or sheet of an appropriate thickness at the bottom end of the resin foam 131 filling area to suppress the flow of the uncured resin foam 131.

Furthermore, if there is a possibility that water may enter the interior of the structure 1 from portions other than the extension portion 11 or from the connection between the extension portion 11 and portions other than the extension portion 11, after performing ST01 and before performing ST02, the worker may take measures such as spraying a resin material from inside or outside the structure 1 to the portions where water may enter, thereby sealing the route of seawater intrusion. When spraying the resin material from the outside, the worker may spray the resin material directly onto the target area using a sprayer, etc., but considering work safety, the spraying work may also be performed using a drone, for example, equipped with a spray system for discharging resin foam. The resin material to be sprayed is a material similar to the resin foam 131.

(Cutting step)
After performing ST01, the worker performs ST02.
In carrying out ST02, the worker cuts the structure 1 so as to cross the cavity 12 at the cutting line CUT, which is the underwater portion of the extension portion 11, and collapses the cut structure 1 as a whole, laying it on the water surface WS.
Cutting means include laser cutting, electric saws, water cutters, and welding, but the worker may select the cutting means depending on the circumstances, such as the material of the extension portion 11, the thickness between the outer and inner surfaces of the extension portion 11, the size of the extension portion 11, environmental conditions, construction period, and regulations regarding construction work.
Before cutting, the worker may remove the portions of the structure 1 other than the extension portion 11 .

When the hardened resin foam 131 is adhered to the inner wall 14 of the extension section 11, the resin foam 131 not only prevents leakage of the residue RS, but also prevents water from entering the cavity 12 when the cut structure 1 is laid on the water surface WS. This also makes it easier for the structure 1 to float on the water surface WS.

If necessary, workers may install floats on the structure 1 lying on the water surface WS to prevent it from sinking, or if filling the cavity 12 with resin foam 131 sufficiently prevents water from entering the cavity 12 and prevents the structure 1 from sinking, then installation of floats may be omitted.

Furthermore, in case of any leakage of the residue RS, the worker may surround the structure 1 that has been cut and is floating on the water surface WS with a fence or the like to prevent the residue RS from spreading.
Furthermore, the worker may prepare dispersants, gelling agents, oil absorbents, etc. in case of leakage of the residue RS.
When cutting the structure 1, if the structure 1 falls over forcefully, the structure 1 itself may be damaged, causing the residue RS to leak, or the large impact or splashes of water may damage floats or fences that have been installed in advance around the area where the structure 1 falls. Therefore, the worker may support the structure 1 with a crane or the like and gradually fall it over.

When gradually tipping the structure 1, the worker may float a raft as a float at the intended tipping position, and then slowly tip the structure 1 onto the raft. In this case, multiple rafts may be provided.

(Disassembly process)
After performing ST02, the worker performs ST03.
In performing ST03, the worker disassembles the cut structure 1.
In this case, the worker can tow the cut structure 1, floating it on the water surface WS, to a location where it can be disassembled, and disassemble the structure 1 into small parts for disposal.

(Action and effect)
According to the cutting method of this embodiment, the residue RS remaining in the structure 1 is less likely to flow out of the structure 1.
Therefore, the outflow of materials from the structure 1 onto the water surface WS when the structure 1 is cut is suppressed.

Furthermore, the cutting method of this embodiment prevents residue RS from leaking out of the extension portion 11 to the water surface WS or from leaking out of residue RS to the water surface WS via the extension portion 11.

Furthermore, according to the cutting method of this embodiment, even if the structure 1 falls onto the water surface WS, the residue RS remaining in the partitioned cavity 12 is unlikely to flow out onto the water surface WS.
Therefore, the outflow of residue RS onto the water surface WS is suppressed.

Furthermore, according to the cutting method of this embodiment, the worker can close even a narrow gap by applying the resin foam 131 .
Therefore, the operator can easily partition cavities 12 of various sizes and shapes.

Furthermore, according to the cutting method of this embodiment, a resin material is sprayed onto the outside of the structure 1 before cutting, thereby preventing the residue RS from leaking to the water surface WS from areas that are difficult to suppress with the sealing material 13.

Second Embodiment
A cutting method according to the second embodiment will be described with reference to FIGS.
The cutting method of this embodiment is the same as the cutting method of the first embodiment, except for the points described below.

(Cutting method procedure)
In this embodiment, in performing ST01, the worker partitions the cavity 12 in the structure 1 with the sealing material 13 including the balloon 132.
4 , in ST01, the worker inflates and installs the balloon 132 in the portion of the cavity 12 above the cutting line CUT so as to plug the cavity 12. At this time, the worker installs the balloon 132 so that the balloon 132 contacts the inner wall 14 around the entire circumference of the stretched portion 11. The worker also installs the balloons 132 at both the top and bottom of the cavity 12 so that the balloon 132 and the inner wall 14 of the stretched portion 11 seal off the majority of the cavity 12, thereby sealing off the majority of the cavity 12.
When it is necessary to install the balloon 132 in a location where it is difficult to access the cavity 12 from outside the structure 1, an operator may use the opening OP provided in the extension portion 11 to install the balloon 132 in the cavity 12 or inflate the balloon 132. After the balloon 132 is installed or inflated, the opening OP is sealed with a door, a cover, or the like.

The shape of the balloon 132 may be any shape that, when inflated, adheres closely to the inner wall 14, preventing leakage of the residue RS and preventing water from entering. For example, the inflated shape may be cylindrical, spherical, or truncated conical, but is not limited to these.

The size of the balloon 132 is preferably somewhat larger than the inner diameter of the extension portion 11 so that it can adhere closely to the inner wall 14 when inflated and be fixed to the inner wall 14 by the inflation force of the balloon 132.

The material of the balloon 132 may be, but is not limited to, a rubber sheet, a rubberized cloth, or the like. The operator may stack multiple layers of rubber sheet or rubberized cloth. To prevent gas, residue RS, or water from passing through the layers of the balloon 132, the operator may insert a thin film made of a material that is impermeable to gas, residue RS, and water between the layers of the balloon 132.
Examples of rubber include, but are not limited to, chlorosulfonated polyethylene rubber used in rescue boats, chloroprene rubber used in balloons, and urethane.
The fibers contained in the rubberized fabric include, but are not limited to, polyester fibers, aramid fibers, and polyethylene fibers.

When the inflated balloon 132 is tightly attached to the inner wall 14, the balloon 132 prevents the residue RS from leaking and also prevents water from entering the cavity 12 when the cut structure 1 is laid on the water surface WS. This also makes it easier for the structure 1 to float on the water surface WS.

Furthermore, the worker may spray the reinforced resin foam 133 before hardening onto the contact area between the balloon 132 and the inner wall 14 as shown in Figure 5, and then harden it to improve the sealing ability against oil and seawater. The material of the reinforced resin foam 133 is the same as that of the resin foam 131.

The balloons 132 may be installed in three or more locations to more reliably prevent leakage of residual RS, rather than just two locations, or may be installed in only one location if this prevents leakage of residual RS.

The appropriate size of the balloon 132 for preventing leakage of residue RS and preventing water intrusion will be confirmed in advance through testing, etc.

To prevent the balloon 132 from shifting from its installed position, the worker can stretch a net over the lower end of the installation position of the balloon 132, and if necessary, the upper and lower ends, to prevent the balloon 132 from shifting from its installed position. Alternatively, the worker can install a jig between the outer surface of the balloon 132 and the inner wall 14 to fasten the balloon 132 to the inner wall 14, and secure the balloon 132 in the appropriate position by fastening it.

If the internal pressure of balloon 132 decreases after balloon 132 is installed before towing ends and structure 1 is pulled onto land, a system for replenishing gas (air) into balloon 132 in response to the decrease in internal pressure may be installed inside structure 1, etc. when balloon 132 is installed.
After the structure 1 is transported to the disassembly site, the worker deflates and removes the balloon 132 before disassembling the structure 1, and if there is no damage to the balloon 132, the balloon 132 may be reused. This also makes it possible to reduce the amount of industrial waste generated when the structure 1 is cut.

Following the execution of ST01, the worker performs ST02, which is the same as in the first embodiment.

(Action and effect)
The cutting method of this embodiment has the same effects as those of the first embodiment.

In addition, according to the cutting method of this embodiment, the worker can easily close the gaps throughout the entire balloon 132 by inflating the balloon 132 .
Therefore, it is easy for the worker to partition the large cavity 12 .

Furthermore, according to the cutting method of this embodiment, the worker can recover the balloon 132 by deflating the balloon 132 before disassembling the structure 1.
Therefore, the operator can reuse the balloon 132.

Furthermore, according to the cutting method of this embodiment, reinforcing resin foam 133 is sprayed and hardened between the balloon 132 and the inner wall 14 of the structure 1, thereby suppressing leakage of residue RS between the balloon 132 and the inner wall 14.

Third Embodiment
A cutting method according to the third embodiment will be described with reference to FIG.
The cutting method of this embodiment is the same as the cutting method of the first or second embodiment, except for the points described below.

(Cutting method procedure and structure configuration)
As shown in FIG. 6, in the cutting method of this embodiment, the structure 1 to be cut is a mining rig 101 installed on water.
The worker performs a cutting method on the mining rig 101, similar to the first or second embodiment, including a partitioning step (ST01), a cutting step (ST02), and a disassembly step (ST03).

The mining rig 101 is located on the ocean.
The mining rig 101 comprises a pillar portion 111 .
The pillar portion 111 has a cavity 12 inside and extends from the bottom of the water above the water surface WS.
The cavity 12 contains residue RS such as oil, grease, etc.
The cavity 12 extends from underwater to above the water surface WS.

In performing ST01, the worker separates the cavity 12 in the pillar portion 111 with a sealing material 13, in performing ST02, the worker cuts the mining rig 101 so that it crosses the cavity 12 in the underwater part of the pillar portion 111, and in performing ST03, the worker disassembles the cut mining rig 101 into small parts at places where it can be disassembled.
The worker can use the resin foam 131 used in the first embodiment or the balloon 132 used in the second embodiment as the sealant 13 that partitions the cavity 12 .

(Action and effect)
The cutting method of this embodiment has the same effects as those of the first embodiment.

<Fourth embodiment>
A cutting method according to the fourth embodiment will be described with reference to FIG.
The cutting method of this embodiment is the same as the cutting method of the first or second embodiment, except for the points described below.

(Cutting method procedure and structure configuration)
As shown in FIG. 7, in the cutting method of this embodiment, the structure 1 to be cut is a ship 201 .
The worker performs a cutting method on the ship 201, similar to the first or second embodiment, including a partitioning step (ST01), a cutting step (ST02), and a disassembly step (ST03).

The vessel 201 comprises a hull 211 having a cavity 12 therein.
The cavity 12 contains residue RS such as oil, grease, etc.

In carrying out ST01, the worker partitions off the cavity 12 inside the ship's hull 211 with sealing material 13, in carrying out ST02, the worker cuts the ship 201 at the part including the cavity 12 to a size that makes it easy to carry out ST03, and in carrying out ST03, the worker disassembles the cut ship 201 into small parts at a location where they can be disassembled.
The worker can use the resin foam 131 used in the first embodiment or the balloon 132 used in the second embodiment as the sealant 13 that partitions the cavity 12 .

(Action and effect)
The cutting method of this embodiment has the same effects as those of the first embodiment.

Fifth Embodiment
A cutting method according to the fifth embodiment will be described with reference to FIG.
The cutting method of this embodiment is the same as the cutting method of the first or second embodiment, except for the points described below.

(Cutting method procedure and structure configuration)
As shown in FIG. 8, in the cutting method of this embodiment, the structure 1 to be cut is a wind power generation facility 301 installed on water.
The worker performs a cutting method on the wind power generation equipment 301, similar to the first or second embodiment, including a partitioning step (ST01), a cutting step (ST02), and a disassembling step (ST03).

The wind power generation facility 301 is installed on the ocean.
The wind power generation facility 301 includes a tower 311 .
In this embodiment, the tower 311 is a tower-type structure installed on the ocean, and is a large composite structure.
The tower 311 has a cavity 12 inside and extends from the bottom of the water above the water surface WS.
The cavity 12 contains residue RS such as oil, grease, etc.
The cavity 12 extends from underwater to above the water surface WS.

In performing ST01, the worker partitions the cavity 12 inside the tower 311 with sealing material 13, in performing ST02, the worker cuts the wind power generation equipment 301 so that it crosses the cavity 12 in the underwater part of the tower 311, and in performing ST03, the worker disassembles the cut wind power generation equipment 301 into small parts at places where it can be disassembled.
The worker can use the resin foam 131 used in the first embodiment or the balloon 132 used in the second embodiment as the sealant 13 that partitions the cavity 12 .

When implementing ST01, to prevent the outflow of residue RS remaining inside or near the nacelle 312, the worker may partition off the cavity 12 directly below the nacelle 312 with sealing material 13.

If there is a possibility that water may enter the interior of the structure 1 through the nacelle 312 or the connection between the nacelle 312 and the tower 311 of the wind power generation equipment 301, after performing ST01 and before performing ST02, the worker may take measures such as spraying a resin material from inside or outside the wind power generation equipment 301 onto the parts where water may enter, thereby sealing the path of seawater intrusion.

Before performing ST02, the worker may remove the propeller 313 from the wind power generation equipment 301.

(Action and effect)
The cutting method of this embodiment has the same effects as those of the first embodiment.

In addition, the cutting method of this embodiment prevents residue RS from inside the nacelle 312 or near the nacelle 312 from leaking to the water surface WS.

Sixth Embodiment
An operating method according to the sixth embodiment will be described with reference to FIGS.
The partitioning step performed in the operating method of this embodiment is the same as the partitioning step performed in the cutting method of the first or second embodiment, except for the points described below.
The mining rig 101 used in the operating method of this embodiment is similar to the mining rig 101 used in the cutting method of the third embodiment, except for the points described below.

(Operation procedure)
As shown in FIG. 9, an operator performs an operation method for the structure 1, which includes a partitioning step (ST101) and an operating step (ST102).
As shown in FIG. 10 , in the operating method of the embodiment, the structure 1 to be operated is a mining rig 101 .

(Partitioning process)
First, the worker performs ST101.
When performing ST101, the worker partitions off the cavity 12 within the pillar portion 111 with a sealing material 13 to prevent leakage material LK in the mining rig 101 from flowing out to the water surface WS through the pillar portion 111.
The worker can use the resin foam 131 used in the first embodiment or the balloon 132 used in the second embodiment as the sealant 13 that partitions the cavity 12 .

(Operating step)
After performing ST101, the worker performs ST102.
In performing ST102, the worker operates the mining rig 101 to extract oil or gas from the ground below the water surface WS.

(Action and effect)
According to the operating method of this embodiment, leakage material LK in the structure 1, including extracted oil, can be prevented from flowing out onto the water surface WS.
Therefore, the outflow from the structure 1 is suppressed.

Seventh Embodiment
A repair method according to the seventh embodiment will be described with reference to FIGS.
The ship 201 used in the repair method of this embodiment is similar to the ship 201 used in the cutting method of the fourth embodiment, except for the points described below.

(Repair procedure)
As shown in FIG. 11, a worker performs a repair method on a structure 1, the repair method including an identifying step (ST201) and a sealing step (ST202).
As shown in FIG. 12, in the repair method of this embodiment, the structure 1 to be repaired is a ship 201 .

(Identifying step)
First, the worker performs ST201.
In performing ST201, the worker identifies a crack CK extending from a cavity 12 within the hull 211 of the ship 201 to the outer surface 215 of the hull 211.

(Clothing process)
After performing ST201, the worker performs ST202.
When performing ST202, the worker seals the identified crack CK with sealing material 13 to prevent leakage material LK in the cavity 12 inside the ship's hull 211 from flowing out from the crack CK to the outer surface 215 of the ship's hull 211.
The worker can use the resin foam 131 used in the first embodiment or the balloon 132 used in the second embodiment as the sealant 13 for sealing the crack CK.

(Action and effect)
According to the repair method of this embodiment, leakage material LK within the structure 1 can be prevented from flowing out of the structure 1 through the crack CK.
Therefore, the outflow from the structure 1 is suppressed.

<Modification>
The method of each embodiment may be applied to any structure where spills are possible, not just the structures described above.

The structure 1 to which the method of each embodiment is applied may be a structure provided anywhere where there is a possibility of spillage.
Alternatively, the structure 1 may be a structure located on a brackish or freshwater lake.
As another modification, the structure 1 may be a structure provided on the ground.

In the partitioning process of each of the first to sixth embodiments, the worker partitions the cavity 12 using a resin foam 131 or a balloon 132, but any sealing material 13 that can partition the cavity 12 may be used.
Alternatively, the operator may separate the cavity 12 with a metal lid as the sealant 13 .

In the sealing step of the seventh embodiment, the worker seals the crack CK with a resin foam 131 or a balloon 132, but any sealing material 13 that can seal the crack CK may be used.
Alternatively, the worker may close the crack CK with a metal cover as the sealant 13 .

In the fifth embodiment, the worker separates the cavity 12 within the tower 311 of the wind power generation facility 301 with a sealing material 13, but any cavity within the wind power generation facility 301 may be separated.
As a modified example, the worker may partition off cavities within the foundation (monopile, tripile), cavities within the blades, cavities within the nacelle, and the like, within the wind power generation facility 301 .

In the cutting methods of each of the first to fifth embodiments, the worker sprays resin material from the outside of the structure 1, but any process may be performed as long as it can prevent the outflow of residue RS.
Alternatively, the worker may use a drone to cover the structure 1 from the outside with a sheet, completely enveloping the structure 1 and preventing the residue RS from escaping.
As another modification, in the fifth embodiment, the worker may use a drone to cover the nacelle 312 from the outside with a sheet, completely enveloping the nacelle 312 and thereby preventing the outflow of residue RS.

The cutting method of each of the first to fifth embodiments may be applied to any method for cutting a structure.
For example, the cutting method according to each of the first to fifth embodiments may be implemented as a method for dismantling a structure to be dismantled.

Although embodiments of the present disclosure have been described above, these embodiments are presented as examples and are not intended to limit the scope of the disclosure. These embodiments can be implemented in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the disclosure. These embodiments and their variations are included within the scope and spirit of the disclosure.

The present disclosure will be described in more detail below with reference to examples, but the present disclosure is not limited to the following examples.
An example of the sealing material will be described with reference to FIGS.

<Example for confirming the effect of resin foam>
(1. Oil leakage prevention performance confirmation)
In Examples 1 to 4, the worker checked the oil leakage prevention performance of the resin foam 131.
The worker used piping made of the same material as the inner wall of tower 311, which is a large composite structure of the fifth embodiment, and used plunger pump 90 to mix and discharge two-component rigid urethane foam, mixing liquid A (main agent) and liquid B (hardener), and then injected uncured resin foam 131 into one end of the piping, allowing it to harden and seal one end of the piping.
Although the outline of a plunger pump 90 is shown in FIG. 13, the pump for filling resin foam is not limited to this.
The thickness of the resin foam 131 in the axial direction of the pipe was set to four values: 0.3 times, 0.5 times, 0.75 times, and 1.0 times the inner diameter of the pipe.
The other end of the pipe was configured so that it could be closed with a lid.
After the resin foam 131 hardened, the worker injected the same type of oil as that remaining in the nacelle 312 of the fifth embodiment into the piping.
Although no pressure is applied to the oil when the actual machine is dismantled, in order to err on the side of caution in this test, workers applied a pressure of approximately 0.5 atmospheres to the oil, closed the valve, and left it in that state at room temperature for 14 days.
After the holding period ended, the worker visually checked whether there was any oil leakage from the portion sealed with the resin foam 131 and whether the oil pressure had dropped significantly.
The results of this confirmation are shown in FIG.

(2. Seawater intrusion prevention performance verification)
In Examples 5 to 8, in the same manner as in "1. Confirmation of oil leakage prevention performance" above, the worker sealed one end of the pipe with resin foam 131, capped the other end, and poured water into the pipe. In this leakage confirmation test, the worker used tap water instead of seawater. Thereafter, the worker performed the same operations as in "1. Confirmation of oil leakage prevention performance" above.
Assuming that the inner diameter of the cut portion of the tower 311 is approximately 3 m and that approximately half of that, or 1.5 m, is submerged in seawater, a maximum hydrostatic pressure equivalent to 1.5 m (approximately 0.015 MPa) will be applied to the resin foam 131. However, in order to be on the safe side, the worker set the water pressure to 0.05 MPa and kept it in that state at room temperature for 14 days.
After the holding period had ended, the worker visually checked whether there was any water leakage from the portion sealed with the resin foam 131, and also checked whether the water pressure had dropped significantly.
The results of this confirmation are shown in FIG.

<Example for confirming the effect of balloons>
(1. Oil leakage prevention performance confirmation)
In Examples 9 to 13, the worker used piping made of the same material as the inner wall of tower 311, which is a large composite structure of the fifth embodiment. He placed balloon 132, which becomes cylindrical when inflated, at one end of the piping in an uninflated state, injected air to inflate balloon 132, and secured balloon 132 to the end of the piping. The outer diameter of balloon 132 in the inflated state was 1.2 times the inner diameter of the piping, and the length of balloon 132 in the axial direction of the piping was set to three values: 0.5, 0.75, and 1.0 times the inner diameter of the piping. The air pressure of balloon 132 was 0.05 MPa.
After inflating the balloon 132, the worker also prepared a test specimen in which the contact area between the inner surface of the pipe and the balloon 132 was sprayed with hard urethane resin foam as reinforcing resin foam 133 to improve adhesion. The side to which the reinforcing resin foam 133 was sprayed was the side that could be accessed after inflating the balloon 132, and the thickness of the foam sprayed at the contact area between the inner surface of the pipe and the balloon 132 was approximately 1/20 to 1/10 of the inner diameter of the pipe (the inner diameter of the tower 311 in the actual device) at its thickest point.
The other end of the pipe was designed to be closable with a lid.
After the balloon 132 was installed, the worker injected the same type of oil as that remaining in the nacelle 312 portion of the piping.
Although no pressure is applied to the oil when the actual machine is dismantled, in order to err on the side of caution in this test, workers applied a pressure of approximately 0.5 atmospheres (0.05 MPa) to the oil, closed the valve, and left it in that state at room temperature for 14 days.
After the holding period ended, the worker visually checked whether there was any oil leakage from the portion sealed with the balloon 132, and also checked whether the oil pressure had dropped significantly.
The results of this confirmation are shown in FIG.

(2. Seawater intrusion prevention performance verification)
In Examples 14 to 18, in the same manner as in "1. Confirmation of oil leakage prevention performance" above, the worker sealed one end of the pipe with balloon 132, capped the other end, and injected water into the pipe.
After inflating the balloon 132, the worker also prepared a test specimen in which a hard urethane resin foam was sprayed as a reinforcing resin foam 133 at the contact point between the inner surface of the pipe and the balloon 132 to improve adhesion.
Assuming that the inner diameter of the cut portion of tower 311 is approximately 3 m and that approximately half of that, or 1.5 m, is submerged in seawater, a maximum hydrostatic pressure equivalent to a water depth of 1.5 m (approximately 0.015 MPa) will be applied to balloon 132. However, in order to be on the safe side, the worker set the water pressure to 0.05 MPa and kept it in that state at room temperature for 14 days.
After the holding period had ended, the worker visually checked whether there was any water leakage from the portion sealed with the balloon 132, and also checked whether the water pressure had dropped significantly.
The results of this confirmation are shown in FIG.

<Additional Notes>
The method according to the above-described embodiment can be understood, for example, as follows.

(1) In the cutting method according to the first aspect, the cavity 12 within the structure 1 is partitioned with a sealing material 13, and the structure 1 is then cut.

According to this embodiment, the residue RS remaining in the structure 1 is less likely to flow out of the structure 1.
Therefore, the outflow of materials from the structure 1 during cutting is suppressed.

(2) The cutting method according to the second aspect is the cutting method according to (1), in which the structure 1 has an extension portion 11 having the cavity 12.

This feature prevents residue RS from leaking out of the extension section 11 or through the extension section 11.

(3) The cutting method according to the third aspect is the cutting method (1) or (2) in which the structure 1 extends from underwater above the water surface WS.

According to this embodiment, even if the structure 1 falls onto the water surface WS, the residue RS remaining in the partitioned cavity 12 is unlikely to flow out onto the water surface WS.
Therefore, the outflow of residue RS onto the water surface WS is suppressed.

(4) A cutting method according to a fourth aspect is any one of the cutting methods (1) to (3), in which the sealing material 13 includes a resin foam 131.

According to this aspect, by applying the resin foam 131, the worker can seal even a small gap.
Therefore, the worker can easily partition cavities 12 of various sizes and shapes.

(5) The cutting method according to the fifth aspect is any one of the cutting methods (1) to (4) in which the sealing material 13 includes a balloon 132.

According to this aspect, the worker can easily close the gaps throughout the entire balloon 132 by inflating the balloon 132 .
Therefore, it is easy for the worker to partition the large cavity 12 .
Furthermore, according to this embodiment, the worker can recover the balloon 132 by deflating the balloon 132 before disassembling the structure 1.
Therefore, the operator can reuse the balloon 132.

(6) A cutting method according to the sixth aspect is the cutting method (5), in which a reinforcing resin foam 133 is sprayed and solidified between the balloon 132 and the inner wall 14 of the structure 1 before the cutting.

This feature prevents leakage of residue RS between the balloon 132 and the inner wall 14.

(7) A cutting method according to the seventh aspect is any of the cutting methods (1) to (6), in which a resin material is sprayed from the outside of the structure 1 before the cutting.

This embodiment prevents leakage of residue RS from areas that are difficult to prevent with the sealing material 13.

(8) The demolition method according to the eighth aspect is a method for demolition of a structure that includes any one of the cutting methods (1) to (7).

According to this embodiment, the residue RS remaining in the structure 1 is less likely to flow out of the structure 1.
Therefore, the outflow of materials from the structure 1 during cutting is suppressed.

(9) The repair method according to the ninth aspect involves identifying a crack CK extending from a cavity 12 within a structure 1 to the outer surface 215 of the structure 1, and sealing the crack CK with a sealant 13.

According to this aspect, leakage material LK within the structure 1 can be prevented from flowing out of the structure 1 through the crack CK.
Therefore, the outflow from the structure 1 is suppressed.

(10) In the operating method according to the tenth aspect, the cavity 12 within the structure 1 is partitioned with a sealing material 13, and the structure 1 is operated.

According to this aspect, leakage of materials from the structure 1 can be prevented.
Therefore, the outflow from the structure 1 is suppressed.

1 Structure 11 Extension 12 Cavity 13 Sealing material 14 Inner wall 90 Plunger pump 101 Mining rig 111 Pillar 131 Resin foam 132 Balloon 133 Reinforced resin foam 201 Ship 211 Hull 215 Outer surface 311 Tower 312 Nacelle 313 Propeller CK Crack CUT Cutting line LK Leakage material OP Opening RS Residue WS Water surface

Claims (6)

a step of partitioning the cavity in a structure having an extension portion with a cavity and extending from underwater to above the water surface with a sealing material;
cutting the structure along a cutting line that is the underwater portion of the extension;
Including,
the encapsulant includes a resin foam;
the cavity contains residue;
In the partitioning step, the resin foam is filled into the upper and lower parts of the cavity above the cutting line so that the residue is sealed between the resin foam and the inner wall of the extension portion;
the sealing material comprises a balloon;
Cutting method. In the partitioning step, the resin foam is filled into the cavity by utilizing an opening provided in the extension portion.
The cutting method according to claim 1 . The residue is oil or grease.
The cutting method according to claim 1 or 2. The cutting method according to claim 1 , wherein a reinforcing resin foam is sprayed between the balloon and the inner wall and hardened before the cutting step. a step of partitioning the cavity in a structure having an extension portion with a cavity and extending from underwater to above the water surface with a sealing material;
cutting the structure along a cutting line that is the underwater portion of the extension;
Including,
the encapsulant includes a resin foam;
the cavity contains residue;
In the partitioning step, the resin foam is filled into the upper and lower parts of the cavity above the cutting line so that the residue is sealed between the resin foam and the inner wall of the extension portion;
Before the cutting step, a resin material is sprayed from the outside of the structure .
Cutting method. A method for dismantling a structure, comprising the cutting method according to any one of claims 1 to 5 .