JP6986378B2 - Piping removal method - Google Patents

Description

This disclosure relates to a method of removing pipes.

For example, when dismantling a chimney with asbestos lined inside or removing pipes in a nuclear power plant, it is necessary to cut and remove the pipes while preventing the scattering of dust inside the pipes. Therefore, for example, a step of inserting a tube corresponding to the length of the chimney into the inside of the chimney in a contracted state, a step of expanding the tube so as to create a space between the inner wall of the chimney, and the inner wall of the chimney. The step of filling the space between the inflated tube with the foaming agent and the chimney whose inner wall is covered with the foaming agent are sequentially cut into round slices, and the cut chimneys are sequentially cut each time. , And a method of disassembling the chimney, which comprises a step of removing the chimney (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2003-343827

However, in the method of disassembling the chimney described in the above-mentioned patent document, the inner wall of the chimney is covered with the foaming agent, but since the tube is taken out from the inside of the chimney when the chimney is cut, the foaming agent exhibits a hollow shape. Therefore, when cutting the chimney, the foaming agent may be peeled off from the inner wall of the chimney and asbestos on the inner wall may be scattered around.

In view of the above circumstances, at least one embodiment of the present invention aims to provide a pipe removing method for removing dust and the like inside the pipe while suppressing the scattering.

(1) The method for removing pipes according to at least one embodiment of the present invention is
It is a pipe removal method that removes a part to be removed, which is a part of the pipe, by cutting the pipe at a predetermined cutting position.
An injection foaming step of injecting and foaming the foamable resin before foaming into the inside of the pipe so that at least the cutting position of the pipe is solid with the foamable resin after foaming.
After the injection foaming step, at least a cutting / removing step of cutting the pipe at the cutting position and removing the removal target portion is provided.

According to the method (1) above, the injection foaming step of injecting the foamable resin before foaming into the inside of the pipe and foaming it so that at least the cutting position of the pipe is solid with the foamable resin after foaming. After the injection foaming step, at least a cutting / removing step of cutting the pipe at the cutting position and removing the removal target portion is provided.
If the foamable resin inside the pipe is hollow at the cutting position, the foamable resin may peel off from the inner peripheral surface of the pipe when the pipe is cut at the cutting position, and the pipe is cut and removed. Occasionally, dust or the like adhering to the inner peripheral surface of the pipe may be scattered around.
However, according to the method (1) above, since the inside of the pipe is solid with foamable resin at the cutting position, the inner peripheral surface of the pipe is formed in the radial direction of the pipe by the foamable resin after foaming at the cutting position. Pressed outward. As a result, by cutting the pipe at the cutting position, even if the adhesive strength between the foamable resin and the inner peripheral surface of the pipe is reduced due to the influence of vibration, impact, and heat during cutting, the foamable resin is inside the pipe. It becomes difficult to peel off from the peripheral surface, and it becomes easy to keep the inner peripheral surface of the pipe on the cut surface in a state of being covered with the foamable resin. Therefore, it is possible to suppress the scattering of dust and the like adhering to the inner peripheral surface of the pipe to the surroundings when the pipe is cut and removed.

(2) In some embodiments, in the method (1) above, before the injection foaming step, a flow regulation that regulates the flow range of the foamable resin before foaming in the pipe axis direction is regulated inside the pipe. Further provided with an installation step for installing the member.

According to the method (2) above, before the injection foaming step, an installation step of installing a flow control member for regulating the flow range of the foamable resin in the pipe axis direction before foaming is further provided inside the pipe. The flow range of the foamable resin before foaming in the pipe axis direction can be regulated. As a result, the range to be filled with the foamed resin inside the pipe can be appropriately set by installing the flow control member, so that the cutting position is solid with the foamed resin regardless of the layout of the pipe. , It is possible to inject a foamable resin before foaming into the inside of the pipe and foam it. Therefore, regardless of the layout of the pipe, it is possible to suppress the scattering of dust and the like adhering to the inner peripheral surface of the pipe when the pipe is cut and removed.

(3) In some embodiments, in the method of (1) above,
The removal target portion includes a first removal target portion and a second removal target portion adjacent to the first removal target portion in the pipe axial direction of the pipe.
In the case of further removing the second removal target part which is a part of the pipe after removing the first removal target part of the pipe.
In the injection foaming step, the flow of the foamed resin remaining inside the pipe after the removal of the first removal target portion regulates the flow range of the foamable resin before foaming in the pipe axis direction. Used as a regulatory member.

According to the method (3) above, when the second removal target part, which is a part of the piping after the first removal target part is removed, is further removed, the injection foaming step is performed after the first removal target part is removed. The foamable resin after foaming remaining inside the pipe is used as a flow control member for regulating the flow range of the foamable resin before foaming in the pipe axis direction. That is, when the pipe is removed by repeating the injection foaming step and the cutting / removal step, the foamable resin after foaming related to the previous injection foaming step that remains inside the pipe after the first removal target portion is removed. Can be used as a flow control member that regulates the flow range of the foamable resin in the pipe axis direction before foaming in this injection foaming step.
As a result, when the pipe is removed by repeating the injection foaming step and the cutting / removal step, the number of times that the flow control member is separately installed can be reduced, so that the pipe can be removed efficiently.

(4) In some embodiments, in any of the methods (1) to (3) above, the injection foaming step is located on the other side of the cutting position on at least one side in the pipe axis direction of the removal target portion. The foamable resin before foaming is injected into the inside of the pipe and foamed so that the foamable resin after foaming becomes solid over the cutting position.

According to the method (4) above, in the injection foaming step, the foamed resin becomes solid from the cutting position on at least one side in the pipe axis direction of the removal target portion to the cutting position on the other side. Since the foamable resin before foaming is injected into the inside of the pipe and foamed, the inside becomes solid with the foamable resin over the entire part to be removed. As a result, the process can be simplified as compared with the case where a region where the foamable resin does not exist is provided in a part of the removal target portion as described later.
Further, for example, even when it is necessary to further cut the removal target portion after removal at the removal destination, it is possible to suppress the scattering of dust and the like adhering to the inner peripheral surface of the removal target portion to the surroundings.

(5) In some embodiments, in any of the methods (1) to (3) above, the injection foaming step is a first region including a cutting position on one side in the pipe axis direction of the removal target portion. And the second region including the cutting position on the other side in the pipe axis direction of the removal target portion becomes solid with the foamable resin after foaming, and the second region between the first region and the second region is formed. The foamable resin before foaming is injected into the inside of the pipe and foamed so that the foamable resin after foaming does not exist in the three regions.

According to the method (5) above, the first region including the cutting position on one side in the pipe axis direction of the removal target portion and the second region including the cutting position on the other side in the pipe axis direction of the removal target portion are formed. Since the foamable resin after foaming becomes solid, the foamable resin after foaming becomes solid at one end and the other end in the pipe axis direction in the removal target portion. Further, according to the method (5) above, the foamable resin after foaming does not exist in the third region between the first region and the second region in the removal target portion. That is, it is possible to provide a region in which the foamable resin does not exist in a part of the removal target portion.
As a result, it is possible to suppress the amount of the foamable resin used and suppress the cost increase while making both ends of the part to be removed solid with the foamable resin after foaming. In particular, when the length of the part to be removed in the pipe axis direction is long, the effect of suppressing the cost increase is high.
Further, since the weight of the foamable resin filled inside the removal target portion can be suppressed, the weight increase due to the injection of the foamable resin in the removal target portion can be suppressed, and the removal target portion can be easily moved.

(6) In some embodiments, in any of the above methods (1) to (5), the removal target portion includes a curved tube portion.

For example, as a known method for disassembling a chimney, a step of inserting a tube corresponding to the length of the chimney into the inside of the chimney in a contracted state and a step of expanding the tube so as to create a space between the inner wall of the chimney. The step of filling the space between the inner wall of the chimney and the inflated tube with a foaming agent, and the chimney with the inner wall covered with the foaming agent are sequentially cut into round slices, and the cut chimney is cut. A method of dismantling a chimney is known, which comprises a step of sequentially removing each time the chimney is cut, and a method of disassembling the chimney. This known method of dismantling a chimney includes a step of inflating the tube so that a space is created between the chimney and the inner wall of the chimney. Since it is difficult to inflate the tube, it is difficult to apply a known chimney dismantling method to the removal of the pipe including the curved pipe portion.
On the other hand, according to the method (6) above, even in a pipe including a curved pipe portion such as an elbow portion, the pipe is piped so that at least the cutting position of the pipe is solid with the foamed resin after foaming. It is possible to carry out an injection foaming step in which a foamable resin before foaming is injected into the inside of the pipe and foamed, and a cutting / removal step in which the pipe is cut at the cutting position and the removal target portion is removed after the injection foaming step. .. As a result, even if the pipe includes a curved pipe portion such as an elbow portion, the pipe can be cut and removed by suppressing the scattering of dust and the like adhering to the inner peripheral surface of the pipe to the surroundings.

(7) In some embodiments, in any of the above methods (1) to (6),
The effervescent resin is a two-component mixed type resin in which a first liquid and a second liquid are mixed and foamed.
In the injection foaming step, a filling device having a sealing portion that abuts and seals the outer peripheral surface of the pipe and a mixing nozzle that mixes the first liquid and the second liquid is used, and the sealing portion is sealed in the pipe. The filling port opened in the pipe is sealed by abutting on the outer peripheral surface of the pipe, and the first liquid and the second liquid mixed by the mixing nozzle are injected into the inside of the pipe through the filling port. And foam.

According to the method (7) above, since a filling device having a mixing nozzle for mixing the first liquid and the second liquid is used, the first liquid and the second liquid are mixed in advance in carrying out the injection foaming step. Since it is not necessary, work efficiency is improved. Further, since the mixture of the first liquid and the second liquid is injected into the inside of the pipe immediately after the first liquid and the second liquid are mixed, the first liquid and the second liquid are mixed and then foamed. Even if the time required to complete the foaming of the sex resin is relatively short, the desired range in the pipe can be filled with the foamed resin.
Further, according to the method (7) above, a filling device having a sealing portion that abuts and seals the outer peripheral surface of the pipe is used, and the filling port opened in the pipe by abutting the sealing portion on the outer peripheral surface of the pipe. Is sealed, and a mixture of the first liquid and the second liquid is injected into the inside of the pipe and foamed. As a result, for example, even when the filling port is provided on the lower surface of the pipe, the mixture of the first liquid and the second liquid leaks to the outside when the mixture of the first liquid and the second liquid is injected. Can be suppressed. Therefore, since the restriction on the position of the filling port can be relaxed, it becomes easy to provide the filling port, and the pipe removal work can be made more efficient.

(8) In some embodiments, in any of the above methods (1) to (7),
In the injection foaming step, the foamable resin before foaming is injected into the inside of the pipe through a filling port opened in the pipe.
The filling port is a confirmation port for confirming the completion of foaming of the foamable resin injected into the inside of the pipe, and an air at the time of expansion due to foaming of the foamable resin injected into the inside of the pipe. Also serves as at least one of the outlets.

According to the method (8) above, the filling port is a confirmation port for confirming the completion of foaming of the foamable resin injected into the inside of the pipe, and the foaming resin injected into the inside of the pipe. It also serves as at least one of the air vents when expanding due to foaming. As a result, the number of openings provided in the pipe can be suppressed, so that the man-hours for providing openings in the pipe can be suppressed, and the work of removing the pipe can be made more efficient.

(9) In some embodiments, in any of the above methods (1) to (8), the foaming ratio of the effervescent resin is 1.3 times or more and 10 times or less.

According to the method (9) above, since the foaming ratio of the foamable resin is 1.3 times or more, the amount of the foamable resin used can be suppressed and the cost increase can be suppressed. Further, since the foaming ratio of the foamable resin is 1.3 times or more, the weight increase of the part to be removed including the foamable resin after foaming can be suppressed, and the removal work can be facilitated.
Generally, the foaming ratio of a foamable resin is affected by the ambient temperature at the time of construction, and the foaming ratio increases when the ambient temperature is high, and decreases when the ambient temperature is low. Therefore, when the foaming ratio exceeds 10 times, the variation in the foaming ratio due to the ambient temperature becomes large, and the force that the foamable resin after foaming presses the inner peripheral surface of the pipe toward the radial outer side of the pipe is also applied for each construction. There is a risk that the variation will increase.
However, according to the method (9) above, since the foaming ratio of the foamable resin is 10 times or less, the force of the foamed resin after foaming to press the inner peripheral surface of the pipe toward the radial outer side of the pipe. Can be suppressed from being scattered from construction to construction. This makes it possible to provide a method for removing pipes that is not easily affected by the ambient temperature.

(10) In some embodiments, in any of the methods (1) to (9) above, the effervescent resin is an effervescent silicone.

According to the method (10) above, since the foamable resin is foamed silicone, the heat resistant temperature of the foamable resin is improved as compared with the case where urethane foam, polystyrene foam, or the like is used as the foamable resin. As a result, the foamable resin after foaming is less likely to be affected by the heat at the time of cutting, so that it is possible to suppress the scattering of dust and the like adhering to the inner peripheral surface of the pipe at the time of cutting and removing the pipe.

According to at least one embodiment of the present invention, the pipe can be cut and removed while suppressing the scattering of dust and the like inside the pipe.

(A) to (e) are diagrams schematically showing a procedure for removing a pipe by the pipe removing method according to the embodiment. (A) to (e) are diagrams schematically showing a procedure for removing a pipe by a pipe removing method according to another embodiment. It is a flowchart which shows the procedure in the pipe removal method which concerns on some Embodiments. (A) to (c) are schematic diagrams for explaining the pipe removing method according to still another embodiment. It is a schematic diagram explaining the pipe removal method which concerns on still another Embodiment.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention to this, but are merely explanatory examples. No.
For example, expressions that represent relative or absolute arrangements such as "in one direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" are exact. Not only does it represent such an arrangement, but it also represents a tolerance or a state of relative displacement at an angle or distance to the extent that the same function can be obtained.
For example, expressions such as "same", "equal", and "homogeneous" that indicate that things are in the same state not only represent exactly the same state, but also have tolerances or differences to the extent that the same function can be obtained. It shall also represent the existing state.
For example, the expression representing a shape such as a quadrangular shape or a cylindrical shape not only represents a shape such as a quadrangular shape or a cylindrical shape in a geometrically strict sense, but also an uneven portion or a chamfer within the range where the same effect can be obtained. It shall also represent the shape including the part and the like.
On the other hand, the expressions "equipped", "equipped", "equipped", "included", or "have" one component are not exclusive expressions excluding the existence of other components.

1 (a) to 1 (e) are diagrams schematically showing a procedure for removing a pipe by the pipe removing method according to the embodiment. 2 (a) to 2 (e) are diagrams schematically showing a procedure for removing a pipe by a pipe removing method according to another embodiment. FIG. 3 is a flowchart showing a procedure in the pipe removing method according to some embodiments.
In FIGS. 1 (a) to 1 (e) and FIGS. 2 (a) to 2 (e), the vertical direction of the paper surface represents the vertical direction of the pipe. In the examples shown in FIGS. 1 (a) to 1 (e) and FIGS. 2 (a) to 2 (e), the pipe 100 has a first straight pipe portion 101 extending upward and a first straight pipe portion in order from the bottom. It is connected to the upper part of 101 via the elbow portion 104 which is a curved pipe portion, and is connected to the second straight pipe portion 102 extending in the right direction in the drawing and the elbow portion 105 at the right end of the second straight pipe portion 102. It has a third straight pipe portion 103 extending upward. In the examples shown in FIGS. 1 (a) to 1 (e) and FIGS. 2 (a) to 2 (e), the second straight pipe portion 102 is inclined so as to increase in height toward the right side of the drawing. However, the second straight pipe portion 102 may be horizontal, or may be inclined so that the height becomes lower toward the right side of the drawing.

In some embodiments, the pipe 100 is, for example, a nitrogen supply pipe for nitrogen purging in a nuclear plant. For example, when the pipe 100 is cut and removed in a decommissioning operation or the like, if radioactive substances adhere to the inside of the pipe 100 as dust, the radioactive substances adhering to the inside of the pipe 100 when the pipe 100 is cut will be around. There is a risk of scattering. Therefore, when the pipe 100 is cut and removed, it is required to suppress the scattering of radioactive substances adhering to the inside of the pipe 100.
Therefore, in the pipe removal method according to some embodiments, as described below, the pipe 100 is cut and the removal target portion is removed while suppressing the scattering of dust and the like adhering to the inside of the pipe 100. do.

The pipe removal method according to some embodiments is a pipe removal method for removing a part to be removed, which is a part of the pipe, by cutting the pipe at a predetermined cutting position.
An injection foaming step of injecting and foaming the foamable resin before foaming into the inside of the pipe so that at least the cutting position of the pipe is solid with the foamable resin after foaming.
After the injection foaming step, at least a cutting / removing step of cutting the pipe at the cutting position and removing the removal target portion is provided.

In the pipe removing method of some embodiments, in the pipe 100, the second straight pipe portion 102 and the elbow portions 104 and 105 connected to both ends of the second straight pipe portion 102 are the removal target portions 109.
Hereinafter, with reference to FIGS. 1 to 3, a procedure for cutting and removing the removal target portion 109 according to some embodiments from the pipe 100 at the cutting positions 109a and 109b will be described.

(Installation step S10)
As shown in FIG. 3, some embodiments of the pipe removal method further include an installation step S10, which is performed prior to the injection foaming step S20.
In the installation step S10, in order to regulate the flow range of the foamable resin injected into the pipe 100 in the pipe axis direction in the injection foaming step S20 described later, that is, to prevent leakage of the foamable resin, FIGS. As shown in 2 (b), an expansion type flow control member 11A is installed inside the pipe 100 as the flow control member 11.

The inflatable flow control member (hereinafter, also simply referred to as a flow control member) 11A expands in the pipe 100 to form the pipe 100, such as a cloth bag coated with rubber or a rubber balloon. It is intended to block. The flow control member 11A is inserted into the inside of the pipe 100 from the outside of the pipe 100 through a hole made in the pipe 100, and when it swells inside the pipe 100 by, for example, nitrogen gas or compressed air, the pipe 100 is closed. Let me. As a result, the inside of the pipe 100 is sealed with the flow control member 11A.
The flow regulating member 11A may be inserted into the inside of the pipe 100 from the outside of the pipe 100 via the filling port 106 described later.

In one embodiment shown in FIG. 1, the piping is made solid with the foamed resin from the cutting position 109a on at least one side in the pipe axis direction of the removal target portion 109 to the cutting position 109b on the other side. A foamable resin before foaming is injected into the inside of 100 and foamed. Therefore, in one embodiment shown in FIG. 1, the flow regulating member 11A is located on the lowermost side along the pipe axis direction of the pipe 100 within the range in which the foamed resin fills the inside of the pipe 100 with the foamed resin as described later. To place.

Further, in another embodiment shown in FIG. 2, the first region 111 including the cutting position 109a on one side in the pipe axis direction of the removal target portion 109 and the cutting position on the other side in the pipe axis direction of the removal target portion 109. The second region 112 including 109b becomes solid with the foamable resin after foaming, and the foamable resin after foaming does not exist in the third region 113 between the first region 111 and the second region 112. Inject the foamable resin before foaming into the inside of the pipe 100 and foam it. Therefore, in the other embodiment shown in FIG. 2, the flow control member 11A is arranged at a position corresponding to both ends of the first region 111 along the pipe axis direction, and is along the pipe axis direction of the second region 112. The flow control member 11A is arranged at a position corresponding to the lower end of both ends. Of both ends of the second region 112 along the pipe axis direction, the position corresponding to the upper end exists in the third straight pipe portion 103 extending upward. Therefore, as shown in FIG. 2B, the flow control member 11A does not have to be arranged at the position corresponding to the upper end portion.

(Injection foaming step S20)
In the injection foaming step S20, the foamable resin before foaming is injected into the inside of the pipe 100 and foamed so that at least the cutting positions 109a and 109b of the pipe 100 are solid with the foamable resin after foaming.
In some embodiments, the effervescent resin is a two-component mixed foam silicone that foams by mixing two liquids, a first liquid and a second liquid, such as a main agent and a curing agent. And cure. The foamable resin will be described in detail later.

In the injection foaming step S20, as shown in FIGS. 1 (b) and 2 (b), from the filling port 106 previously opened in the pipe 100, as shown in FIGS. 1 (c) and 2 (c), The effervescent resin 20 before foaming, which is the liquid after mixing the first liquid and the second liquid, is injected into the pipe 100. In addition, in one embodiment shown in FIG. 1 (b), the filling port 106 is provided above the vicinity of the elbow portion 105 at the right end of the second straight pipe portion 102. That is, in one embodiment shown in FIG. 1 (b), the filling port 106 is provided on the upper surface of the removal target portion 109.
Further, in another embodiment shown in FIG. 2B, the filling port 106 is above the vicinity of the elbow portion 105 at the right end and above the vicinity of the elbow portion 104 at the left end of the second straight pipe portion 102. It is provided in. That is, in the other embodiment shown in FIG. 2B, the filling port 106 is provided on the upper surface of the removal target portion 109.

The foamable resin 20 before foaming injected from the filling port 106 flows downward inside the pipe 100, but the downward flow is restricted by the flow regulating member 11A installed in the installation step S10 described above. Further, in another embodiment shown in FIG. 2, the foamable resin 20 before foaming injected into the first region 111 from the filling port 106 is on the upper side of both ends of the first region 111 along the pipe axis direction. The flow is also regulated by the flow control member 11A installed at the position corresponding to the end of the.

The injection amount of the foamable resin 20 before foaming is appropriately adjusted depending on the size of the range in which the foamable resin after foaming fills the inside of the pipe 100, the foaming ratio, and the like.

As shown in FIGS. 1 (d) and 2 (d), the foamable resin 20 before foaming foams and expands inside the injected pipe 100. Thereby, in one embodiment shown in FIG. 1, the foamable resin 30 is filled from the cutting position 109a on at least one side in the pipe axis direction of the removal target portion 109 to the cutting position 109b on the other side. As a result, the inside of the part to be removed 109 becomes solid with the foamable resin 30.
Further, in another embodiment shown in FIG. 2, the first region 111 including the cutting position 109a on one side in the pipe axis direction of the removal target portion 109 and the cutting position 109b on the other side in the pipe axis direction of the removal target portion 109. The second region 112 including the above is filled with the foamable resin 30 after foaming and becomes solid, but the third region 113 between the first region 111 and the second region 112 is filled with the foamable resin 30 after foaming. Does not exist.

The filling port 106 also serves as an air vent for guiding the gas inside the pipe 100 to the outside of the pipe 100 when the foamable resin foams and expands in the pipe 100. As a result, the number of openings provided in the pipe 100 can be suppressed, so that the man-hours for providing openings in the pipe 100 can be suppressed, and the work of removing the pipe can be made more efficient.

The foamable resin 30 after foaming adheres to the inner peripheral surface of the pipe 100. Further, the foamable resin 30 after foaming presses the inner peripheral surface of the pipe 100 toward the outside of the pipe 100. In other words, the inner peripheral surface of the pipe 100 is pressed toward the radial outer side of the pipe 100 by the foamable resin 30 after foaming. As a result, the foamable resin 30 after foaming comes into close contact with the inner peripheral surface of the pipe 100.

Whether or not the foaming and curing of the foamable resin is completed is determined by, for example, as shown in FIGS. 1 (d) and 2 (d), the foamable resin protruding to the outside of the pipe 100 through the filling port 106. It can be determined by the presence or absence of the protruding portion 31 of the above and the elapsed time from mixing the first liquid and the second liquid.
Further, whether or not the foamable resin 30 after foaming expands and reaches a desired position in the pipe axis direction in the pipe 100 can be determined by, for example, a tapping sound inspection or an ultrasonic inspection.

As described above, the filling port 106 also serves as a confirmation port for confirming the completion of foaming of the foamable resin. As a result, the number of openings provided in the pipe 100 can be suppressed, so that the man-hours for providing openings in the pipe 100 can be suppressed, and the work of removing the pipe can be made more efficient.
As described above, in some embodiments, the filling port 106 is an air vent port at the time of expansion due to foaming of the foamable resin injected into the pipe 100, and the foamable resin injected into the pipe 100. Also serves as a confirmation port for confirming the completion of foaming.
An air vent may be provided separately from the filling port 106, or a confirmation port may be provided separately from the filling port 106.

In one embodiment shown in FIG. 1, in this way, a region wider than the removal target portion 109 is filled with the foamable resin 30 after foaming. That is, in one embodiment shown in FIG. 1, as shown in FIG. 1 (d), the cutting position 109a on one side in the pipe axis direction is included, and extends on both sides in the pipe axis direction with the cutting position 109a in between. The foamed resin 30 is filled from the first region 111 to the second region 112 including the cutting position 109b on the other side in the pipe axial direction and extending on both sides in the pipe axial direction with the cutting position 109b in between.
Further, in another embodiment shown in FIG. 2, as shown in FIG. 2D, the cutting position 109a on one side in the pipe axis direction is included, and extends to both sides in the pipe axis direction with the cutting position 109a in between. The first region 111 and the second region 112 including the cutting position 109b on the other side in the pipe axial direction and extending on both sides in the pipe axial direction across the cutting position 109b are filled with the foamable resin 30 after foaming. Is done.

(Cut and remove step S30)
In the cutting / removing step S30, after the injection foaming step S20, as shown in FIGS. 1 (e) and 2 (e), the pipe 100 is cut at the cutting positions 109a and 109b, and the removal target portion 109 is removed. That is, in the cutting / removing step S30, the pipe 100 is cut at the portion filled with the foamable resin 30 after foaming, and the removal target portion 109 is removed.

The remaining portion of the pipe 100 after the removal target portion 109 is removed has the ends 121 and 122 sealed with the foamable resin 30 after foaming.

As shown in FIGS. 1 (e) and 2 (e), the pipe end of the pipe 100 is closed at the ends 121 and 122 with respect to the remaining portion of the pipe 100 after the removal target portion 109 is removed. The member 125 may be attached.

By repeatedly performing each of the above steps, the pipe 100 can be cut and removed while suppressing the scattering of dust and the like adhering to the inner peripheral surface of the pipe 100 to the surroundings.

In some of the above-described embodiments, the following effects are exhibited.
(1) As described above, in some embodiments, the cutting positions 109a and 109b are solid in the foamable resin 30 after foaming, so that they adhere to the inner peripheral surface of the pipe 100 when the pipe 100 is cut and removed. It is possible to suppress the scattering of dust and the like that had been generated to the surroundings.
If the foamable resin 30 inside the pipe 100 is hollow at the cutting positions 109a and 109b, the foamable resin 30 is removed from the inner peripheral surface of the pipe 100 when the pipe 100 is cut at the cutting positions 109a and 109b. There is a risk of peeling, and there is a risk that dust or the like adhering to the inner peripheral surface of the pipe 100 when the pipe 100 is cut or removed may be scattered around.

However, according to some of the above-described embodiments, since the inside of the pipe 100 is solidified by the foamable resin 30 after foaming at the cutting positions 109a and 109b, the inner peripheral surface of the pipe 100 is the cutting position 109a. At 109b, the foamable resin 30 after foaming presses the pipe 100 toward the outside in the radial direction. As a result, by cutting the pipe 100 at the cutting positions 109a and 109b, even if the adhesive strength between the foamable resin 30 and the inner peripheral surface of the pipe 100 is lowered due to the influence of vibration, impact, and heat during cutting, foaming is performed. The sex resin 30 is less likely to be peeled off from the inner peripheral surface of the pipe 100, and the inner peripheral surface of the pipe 100 on the cut surface is easily kept covered with the foamable resin 30. Therefore, it is possible to suppress the scattering of dust and the like adhering to the inner peripheral surface of the pipe 100 to the surroundings when the pipe 100 is cut and removed.

(2) In some of the above-described embodiments, a flow regulating member 11 for regulating the flow range of the foamable resin 20 before foaming in the pipe axis direction is installed inside the pipe 100 before the injection foaming step S20. Further, step S10 is provided.

As a result, the range filled with the foamed resin 30 inside the pipe 100 can be appropriately set by installing the flow control member 11, so that the cutting position is the foamed resin 30 after foaming regardless of the layout of the pipe 100. The foamable resin 20 before foaming can be injected into the inside of the pipe 100 so as to be solid and foamed. Therefore, regardless of the layout of the pipe 100, it is possible to suppress the scattering of dust and the like adhering to the inner peripheral surface of the pipe 100 when the pipe 100 is cut and removed.

(3) For example, the end portion 122 on the right side of the drawing in FIGS. 1 (e) and 2 (e) is the lower end of the third straight pipe portion 103 extending upward, and is foamable after foaming as described above. It is sealed with resin 30. Therefore, when the third straight pipe portion 103 is removed after the removal target portion 109 is removed, the foamable resin 30 filled in the end portion 122 has the foamable resin 20 before foaming inside the third straight pipe portion 103. It can be used as a flow control member 11 for new injection.

That is, when the pipe 100 is removed by repeatedly executing the above-mentioned injection foaming step S20 and the cutting / removing step S30, the pipe 100 remains inside the pipe 100 after the removal target portion 109 is removed in the previous cutting / removing step S30. The foamable resin 30 after foaming according to the previous injection foaming step S20 can be used as the flow control member 11 for regulating the flow range of the foamable resin 20 before foaming in the pipe axis direction in the current injection foaming step S20.

Here, the removal target portion is the above-mentioned removal target portion 109 as the first removal target portion and the third straight pipe as the second removal target portion adjacent to the first removal target portion in the pipe axis direction of the pipe 100. Part 103 is included. In this case, the pipe removal method according to some embodiments can be expressed as follows. That is, the pipe removal method according to some embodiments is an injection foaming step in the case of further removing the second removal target portion which is a part of the pipe 100 after the first removal target portion is removed from the pipe 100. S20 is a flow control member 11 that regulates the flow range of the foamable resin 30 after foaming remaining inside the pipe 100 after the removal of the first removal target portion in the pipe axis direction of the foamable resin 20 before foaming. Use as.
As a result, when the pipe 100 is removed by repeating the injection foaming step S20 and the cutting / removal step S30, for example, the number of times that the expansion type flow control member 11A is separately installed can be reduced, so that the pipe 100 can be efficiently removed. can.

(4) In one embodiment shown in FIG. 1, the injection foaming step S20 has foamability after foaming from at least one cutting position 109a in the pipe axis direction of the removal target portion 109 to the other cutting position 109b. The foamable resin 20 before foaming is injected into the inside of the pipe 100 so that the resin 30 becomes solid and foamed.

Therefore, the inside of the part to be removed 109 becomes solid with the foamed resin 30 after foaming. As a result, the process can be simplified as compared with the case where the region where the foamed resin 30 does not exist after foaming is provided in a part of the removal target portion 109 as in the other embodiment shown in FIG.
Further, for example, even when it is necessary to further cut the removal target portion 109 after removal at the removal destination, it is possible to suppress the scattering of dust and the like adhering to the inner peripheral surface of the removal target portion 109 to the surroundings.

(5) In another embodiment shown in FIG. 2, the injection foaming step S20 has a first region 111 including a cutting position 109a on one side in the pipe axis direction of the removal target portion 109 and a pipe axis direction of the removal target portion. The second region 112 including the cutting position 109b on the other side of the above becomes solid in the foamable resin 30 after foaming, and the third region 113 between the first region 111 and the second region 112 is formed after foaming. The foamable resin 20 before foaming is injected into the inside of the pipe 100 and foamed so that the foamable resin 30 does not exist.

As a result, it is possible to suppress the amount of the foamable resin used and suppress the cost increase while making both ends of the removal target portion 109 solid with the foamable resin 30 after foaming. In particular, when the length of the removal target portion 109 in the pipe axis direction is long, the effect of suppressing the cost increase is high.
Further, since the weight of the foamable resin filled inside the removal target portion 109 can be suppressed, the weight increase due to the injection of the foamable resin of the removal target portion 109 can be suppressed, and the removal target portion 109 can be easily moved.

(6) In some of the above-described embodiments, the removal target portion 109 includes elbow portions 104 and 105 as curved pipe portions.

For example, as a known method of disassembling a chimney, a step of inserting a tube corresponding to the length of the chimney into the inside of the chimney in a contracted state and a step of expanding the tube so as to create a space between the inner wall of the chimney. The step of filling the space between the inner wall of the chimney and the inflated tube with a foaming agent, and the chimney with the inner wall covered with the foaming agent are sequentially cut into round slices, and the cut chimney is cut. A method of dismantling a chimney is known, which comprises a step of sequentially removing each time the chimney is cut, and a method of disassembling the chimney. This known method of dismantling a chimney includes a step of inflating the tube so that a space is created between the chimney and the inner wall of the chimney. Since it is difficult to inflate the tube, it is difficult to apply a known chimney dismantling method to the removal of the pipe including the curved pipe portion.

On the other hand, in some of the above-described embodiments, even in the pipe 100 including the curved pipe portions such as the elbow portions 104 and 105, at least the cutting positions 109a and 109b of the pipe 100 are the foamable resin 30 after foaming. After the injection foaming step S20 in which the foamable resin 20 before foaming is injected into the inside of the pipe 100 and foamed, and the injection foaming step S20, the pipe 100 is cut at the cutting positions 109a and 109b. It is possible to carry out the cutting / removal step S30 for removing the removal target portion 109. As a result, even in the pipe 100 including the curved pipe portions such as the elbow portions 104 and 105, the pipe 100 is cut and removed by suppressing the scattering of dust and the like adhering to the inner peripheral surface of the pipe 100 to the surroundings. can.

(About foaming resin)
As described above, in some embodiments, the effervescent resin is a two-component mixed type foamed silicone, which is foamed and cured by mixing the first liquid and the second liquid.
Specific products of foamed silicone include, for example, Peneseal (registered trademark) "CT-18" and "CT-18H", which are products of NICHIAS Corporation, and two-component curable foam, which is a product of Shin-Etsu Chemical Co., Ltd. Examples thereof include silicones "KE-513" and "KE-521", and two-component curable foamed silicones "TB5277", "12X195" and "TB5277C" which are products of ThreeBond Co., Ltd.

The foamed silicone used in some embodiments has a heat resistant temperature of about 200 to 250 ° C., and has a heat resistant temperature higher than that of urethane foam, polystyrene foam, or the like. Therefore, the heat resistant temperature of the foamable resin is improved as compared with the case where urethane foam, styrofoam, or the like is used as the foamable resin. As a result, the foamable resin 30 after foaming is less likely to be affected by the heat at the time of cutting, so that it is possible to suppress the scattering of dust and the like adhering to the inner peripheral surface of the pipe 100 at the time of cutting and removing the pipe 100. ..

Further, the foamed silicone used in some embodiments has a foaming ratio of 1.3 times or more and 10 times or less.
Since the foaming ratio of the foamable resin is 1.3 times or more, the amount of the foamable resin used can be suppressed and the cost increase can be suppressed. Further, since the foaming ratio of the foamable resin is 1.3 times or more, the weight increase of the removal target portion 109 including the foamable resin 30 after foaming can be suppressed, and the removal work can be facilitated.

Generally, the foaming ratio of a foamable resin is affected by the ambient temperature at the time of construction, and the foaming ratio increases when the ambient temperature is high, and decreases when the ambient temperature is low. Therefore, when the foaming ratio exceeds 10 times, the variation in the foaming ratio due to the ambient temperature becomes large, so that the foamable resin 30 after foaming presses the inner peripheral surface of the pipe 100 toward the radial outer side of the pipe 100. There is a possibility that the force and the range filled with the foamable resin 30 after foaming will vary greatly from construction to construction.
However, in the foamed silicone used in some embodiments, the foaming ratio is 10 times or less, so that the foamable resin 30 after foaming presses the inner peripheral surface of the pipe 100 toward the radial outer side of the pipe 100. It is possible to prevent the range filled with the foamable resin 30 after foaming and the like from being dispersed depending on the construction. This makes it possible to provide a method for removing pipes that is not easily affected by the ambient temperature.

In some of the above-described embodiments, when the pipe 100 is cut and removed by decommissioning work or the like, each of the above-mentioned steps is performed by remote control.

(About still other embodiments)
Yet another embodiment of the pipe removal method will be described with reference to FIGS. 4 and 5.
In still another embodiment shown in FIGS. 4 and 5, in the injection foaming step S20, the sealing portion 201 that abuts and seals the outer peripheral surface of the pipe 100 and the mixing nozzle that mixes the first liquid and the second liquid. A filling device 200 having 202 is used.
More specifically, the filling device 200 has a discharge unit 210 to which the downstream side (discharge side) of the mixing nozzle 202 is connected, as is well shown in FIG. 4 (a). The discharge portion 210 has a seal portion 201 provided at the opening end 211 on the outlet side. The shape of the opening end 211 exhibits a shape along the outer peripheral surface of the pipe 100. Therefore, as described below, when the opening end 211 is pressed toward the outer peripheral surface of the pipe, the sealing portion 201 is in close contact with the outer peripheral surface of the pipe 100 to seal the filling port 106. The size of the opening end 211 and the seal portion 201 is larger than the size of the filling port 106.

In the filling device 200 shown in FIGS. 4 and 5, the supply pump for supplying the first liquid to the mixing nozzle 202 and the second liquid to the mixing nozzle 202 are not shown on the upstream side of the mixing nozzle 202. The supply pumps that supply are connected to each other. When the first liquid and the second liquid are supplied to the mixing nozzle 202 from these supply pumps, the first liquid and the second liquid are mixed by passing through the mixing nozzle 202 and flow out from the downstream side of the mixing nozzle 202. ..

In still another embodiment shown in FIGS. 4 and 5, in the injection foaming step S20, the seal portion 201 provided at the opening end 211 of the discharge portion 210 of the filling device 200 is brought into contact with the outer peripheral surface of the pipe 100. The filling port 106 opened in the pipe 100 is sealed, and the first liquid and the second liquid mixed by the mixing nozzle 202 are injected into the inside of the pipe 100 through the filling port 106 to be foamed.

For example, in the example shown in FIG. 4, the filling port 106 is provided on the upper surface of the pipe 100, as in some embodiments described above. In this case, as shown by the arrow a in FIG. 4B, the discharge portion 210 of the filling device 200 is pressed from above the pipe 100, and the seal portion 201 is brought into close contact with the outer peripheral surface of the pipe 100 to bring the sealing portion 201 into close contact with the outer peripheral surface of the pipe 100. To seal. After that, as shown by an arrow b in FIG. 4C, the first liquid and the second liquid mixed by the mixing nozzle 202, that is, the effervescent resin 20 before foaming is put into the inside of the pipe 100 via the filling port 106. inject.

Further, for example, in the example shown in FIG. 5, the filling port 106 is provided on the lower surface of the pipe 100. In this case, as shown in FIG. 5, the discharge portion 210 of the filling device 200 is pressed from below the pipe 100, and the seal portion 201 is brought into close contact with the outer peripheral surface of the pipe 100 to seal the filling port 106. Then, as shown by the arrow c, the first liquid and the second liquid mixed by the mixing nozzle 202, that is, the effervescent resin 20 before foaming is injected into the inside of the pipe 100 through the filling port 106.

In the example shown in FIG. 4, since the filling port 106 is provided on the upper surface of the pipe 100, the filling device 200 is separated from the pipe 100 before the foamable resin 20 before foaming is cured, and the filling port 106 is provided. Can be opened.
Further, in the example shown in FIG. 4, since the filling port 106 is provided on the upper surface of the pipe 100, the filling port 106 may be used as the above-mentioned air vent or confirmation port, or may be used as the air vent or the confirmation port. The confirmation port may be provided separately from the filling port 106.

In the example shown in FIG. 5, since the filling port 106 is provided on the lower surface of the pipe 100, the foamable resin is completely cured so that the foamable resin 20 before foaming does not leak from the filling port 106. The filling port 106 is closed by the filling device 200.
In the example shown in FIG. 5, as described above, the filling port 106 is closed by the filling device 200 until the curing of the foamable resin is completed. Will be provided separately.

As described above, in still another embodiment shown in FIGS. 4 and 5, a filling device 200 having a mixing nozzle 202 for mixing the first liquid and the second liquid is used, so that the injection foaming step S20 is carried out. Since it is not necessary to mix the first liquid and the second liquid in advance, the work efficiency is improved. Further, since the mixture of the first liquid and the second liquid is injected into the inside of the pipe 100 immediately after the first liquid and the second liquid are mixed, after the first liquid and the second liquid are mixed. Even if the time required to complete the foaming of the foamable resin is relatively short, the desired range in the pipe 100 can be filled with the foamable resin 30 after foaming.
Further, according to still another embodiment shown in FIGS. 4 and 5, a filling device 200 having a sealing portion 201 that abuts and seals the outer peripheral surface of the pipe 100 is used, and the sealing portion 201 is placed on the outer peripheral surface of the pipe 100. The filling port 106 opened in the pipe 100 is sealed, and a mixture of the first liquid and the second liquid is injected into the inside of the pipe 100 to be foamed. As a result, for example, even when the filling port 106 is provided on the lower surface of the pipe 100 as shown in FIG. 5, the first liquid and the second liquid are injected when the mixture of the first liquid and the second liquid is injected. It is possible to prevent the mixture with the two liquids from leaking to the outside. Therefore, since the restriction on the position of the filling port 106 can be relaxed, the filling port 106 can be easily provided and the pipe removal work can be made more efficient.

The present invention is not limited to the above-described embodiment, and includes a modification of the above-mentioned embodiment and a combination of these embodiments as appropriate.
For example, in the above description, the removal of the piping used in the nuclear power plant has been described as an example, but the scope of the present invention is not limited to the removal of the piping used in the nuclear power plant. For example, the present invention may be applied to the removal of a chimney or a pipe lined with asbestos, or the present invention may be applied to the removal of a pipe to which other dust or the like is attached.

11 Flow control member 11A Inflatable flow control member (flow control member)
20 Effervescent resin (foamable resin before foaming)
30 Foamable resin (foamable resin after foaming)
100 Piping 104, 105 Elbow part 106 Filling port 109 Removal target part 109a, 109b Cutting position 111 First area 112 Second area 113 Third area 200 Filling device 201 Sealing part 202 Mixing nozzle

Claims (9)

It is a pipe removal method that removes a part to be removed, which is a part of the pipe, by cutting the pipe at a predetermined cutting position.
An injection foaming step of injecting and foaming the foamable resin before foaming into the inside of the pipe so that at least the cutting position of the pipe is solid with the foamable resin after foaming.
After the injection foaming step, at least a cutting / removing step of cutting the pipe at the cutting position and removing the removal target portion is provided.
The removal target portion includes a first removal target portion and a second removal target portion adjacent to the first removal target portion in the pipe axial direction of the pipe.
In the case of further removing the second removal target part which is a part of the pipe after removing the first removal target part of the pipe.
In the injection foaming step, the flow of the foamed resin remaining inside the pipe after the removal of the first removal target portion regulates the flow range of the foamable resin before foaming in the pipe axis direction. used as a regulating member, piping removing method. In the injection foaming step, after foaming, a first region including a cutting position on one side in the pipe axis direction of the removal target portion and a second region including a cutting position on the other side in the pipe axis direction of the removal target portion are formed. Before foaming, the inside of the pipe is made solid so that the foamable resin after foaming does not exist in the third region between the first region and the second region. The method for removing a pipe according to claim 1, wherein the foamable resin is injected and foamed. It is a pipe removal method that removes a part to be removed, which is a part of the pipe, by cutting the pipe at a predetermined cutting position.
An injection foaming step of injecting and foaming the foamable resin before foaming into the inside of the pipe so that at least the cutting position of the pipe is solid with the foamable resin after foaming.
After the injection foaming step, at least a cutting / removing step of cutting the pipe at the cutting position and removing the removal target portion is provided.
The injection foaming step is performed so that the inside of the pipe becomes solid with the foamable resin after foaming from at least one cutting position in the pipe axis direction of the removal target portion to the other cutting position. the foaming resin before foaming to the inside of the pipe injection to be foamed, piping removing method. Any of claims 1 to 3, further comprising an installation step of installing a flow control member for regulating the flow range of the foamable resin in the pipe axis direction before foaming inside the pipe before the injection foaming step. The piping removal method described in item 1. The pipe removal method according to any one of claims 1 to 4 , wherein the removal target portion includes a curved pipe portion. The effervescent resin is a two-component mixed type resin in which a first liquid and a second liquid are mixed and foamed.
In the injection foaming step, a filling device having a sealing portion that abuts and seals the outer peripheral surface of the pipe and a mixing nozzle that mixes the first liquid and the second liquid is used, and the sealing portion is sealed in the pipe. The filling port opened in the pipe is sealed by abutting on the outer peripheral surface of the pipe, and the first liquid and the second liquid mixed by the mixing nozzle are injected into the inside of the pipe through the filling port. The method for removing a pipe according to any one of claims 1 to 5, wherein the pipe is foamed. In the injection foaming step, the foamable resin before foaming is injected into the inside of the pipe through a filling port opened in the pipe.
The filling port is a confirmation port for confirming the completion of foaming of the foamable resin injected into the inside of the pipe, and an air at the time of expansion due to foaming of the foamable resin injected into the inside of the pipe. The method for removing a pipe according to any one of claims 1 to 6 , which also serves as at least one of the outlets. The pipe removing method according to any one of claims 1 to 7 , wherein the foaming ratio of the foamable resin is 1.3 times or more and 10 times or less. The method for removing a pipe according to any one of claims 1 to 8 , wherein the foamable resin is foamed silicone.

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