JP3551284B2 - Piping freezing method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a pipe freezing method, and particularly when performing work such as repair and replacement of a pipe, a pipe which ensures that water is hardly stopped in a part of the center of the pipe which is hard to freeze when water is stopped using an ice plug. Related to the freezing method.
[0002]
[Prior art]
Conventionally, for example, as shown in FIG. 7, when repairing / replacement of a cold / hot water pipe or the like used for an air conditioner, a repair / replacement in which a crack or the like has occurred in the middle of a route connecting the pipe 2 from the water tank 1. At the replacement location 3a, the valve 4 interposed between the routes leading to the location 3a is closed, and after the flow of the liquid from the water tank 1 is shut off, repair and replacement work is performed.
[0003]
However, at the repair / replacement location 3b where no valve is arranged in the vicinity, the water of the tank 1 and the pipe 2 is drained, and then the repair / replacement work of the pipe is performed. For this reason, if the water filling after the operation is also taken into consideration, the cost becomes long and expensive. Therefore, in the case of repairing / replacement of a portion like 3b, a freezing method has been considered in which a part of a flow pipe to the repair / replacement portion 3b is formed with a water plug 5 by an ice plug (Japanese Patent Laid-Open No. 51-1979). 102220, JP-A-63-26491).
[0004]
As shown in FIG. 8, the ice plug has a jacket 7 that holds a cooling medium 6 such as liquid nitrogen formed around the pipe 2 on the outer surface of the pipe 2, locally freezes the liquid 8 in the pipe, and makes the ice plug ( An ice stopper 9 is formed to temporarily stop the flow of the liquid inside the pipe.
[0005]
[Problems to be solved by the invention]
However, in order to stop the liquid inside the pipe by using the above-mentioned conventional ice plug, it is necessary to completely freeze the liquid at the center of the pipe. It takes longer to do it. Also, in the case of large-diameter piping, the temperature is balanced with an ice layer of a certain thickness formed on the inner surface of the piping, and the ice plug cannot be applied to large-diameter piping because the temperature does not completely freeze to the center of the piping. was there.
[0006]
Accordingly, an object of the present invention is to provide a pipe freezing method that can form an ice plug inside a pipe in a short time and reliably in a pipe freezing method using an ice plug, and that can be applied to a large-diameter pipe. And
[0007]
[Means for Solving the Problems]
To achieve the above object, a pipe freezing method according to the present invention, a cooling medium to freeze the pipe internal fluid from the pipe surface by using, in the pipe freezing method for water stopping a pipe by ice plugs, existing leading to the pipe The insertion type freezing promoting jig inserted from the opening is guided into the inside of the pipe corresponding to the disposition position of the cooling medium, and is frozen for each jig to form an ice plug.
[0008]
In this case, it is preferable that the insertion type freezing promoting jig is a steel ball.
[0009]
Further, the insertion type freezing promoting jig may be formed of a hollow container, and the cooling medium may be supplied and filled in the hollow container.
[0010]
[Action]
According to the above configuration, the insertion type freezing promoting jig is inserted from the opening of the tank or the like, guided to the ice plug forming portion adjacent to the repair exchange portion, and the freezing volume of the pipe freezing portion is set in the gap between the pipe and the jig. By doing so, it is possible to reduce the number of pipes, and to repair and replace pipes in a short time and reliably. Furthermore, by supplying a cooling medium to the inside of the jig as a hollow container , the effect of accelerating freezing is remarkably increased, and the effect of shortening the time required for forming ice plugs required for repairing and replacing pipes is great. Become.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a method according to the related art will be described with reference to the drawings, and then a specific embodiment of the pipe freezing method according to the present invention will be described.
[0012]
FIG. 1 is an explanatory sectional view showing a conventional pipe freezing method, in which an elastic bag is used as a pipe section reducing jig to promote freezing. A cooling medium 14 such as liquid nitrogen is held on the surface of the pipe 10 via a jacket 12 with the pipe repairing portion interposed therebetween, and an ice plug 16 is formed inside the pipe. The ice plug 16 is formed by the cooling action of the cooling medium 14. When the ice plug 16 is formed inside the pipe, the volume of the ice plug 16 is reduced by installing the elastic bag 18 inside the pipe 10 and expanding the bag. Extremely reduced.
[0013]
FIG. 2 to FIG. 4 show a procedure of a freezing method using a jig for reducing the cross-section of a pipeline made of the elastic bag 18.
[0014]
First, as shown in FIG. 2A, a split T-tube 20 is attached to a repair location of the pipe 10. The split T-tube 20 has half-tubes 22 a and 22 b capable of surrounding the pipe 10, and a branch pipe 24 is provided on one of them. The branch pipe 24 is equipped with a valve 28 that is linked to the handle 26, and a flange 29 is formed at the tip of the branch end 24. This may be a commercially available product.
[0015]
Next, as shown in FIG. 2B, the drill holder 30 is attached via the flange portion 29. The drill holder 30 has a flange portion 32 and can be flange-connected to the split T-tube 20, and has a drill insertion hole 34 formed along the center of the branch tube 24. An electric drill device 37 equipped with a drill 36 is mounted on the drill holder 30, the drill 36 is inserted from the insertion hole 34, and a hole is formed in the pipe wall of the pipe 10 to form a pipe wall hole 38. .
[0016]
After drilling in the pipe 10, with the drill 36 inserted into the drill holder 30, the split T-shaped pipe 20 is moved to a position where the valve 28 can be opened and closed, and the valve 28 is closed and water is stopped. As shown in (3), the drill 36 is removed. At the same time, a pair of elastic bags 18 as a pipe section reduction member are prepared. A supply cylinder 40 for supplying air, liquid nitrogen, or the like is connected to the elastic bag 18 so that the elastic bag 18 can be expanded by opening the cylinder 40.
[0017]
Next, as shown in FIG. 3A, the pair of elastic bags 18 inserted from the drill insertion holes 34 are passed through the tube wall holes 38, and are respectively installed at the ice plug execution positions 42. This may be performed using an operation wire or the like. Then, the cylinder 40 is opened, and the elastic bag 18 is inflated.
[0018]
After the expansion of the elastic bag 18, as shown in FIG. 3 (2), the jacket 12 is installed on the outer peripheral surface of the pipe 10 at the ice plug execution position 42, and the cooling medium 14 such as liquid nitrogen is filled in the jacket 12. An ice plug 16 is formed. The formed ice plug 16 has a small volume between the outer surface of the elastic bag 18 and the inner surface of the pipe 10 because the cross section of the pipeline is reduced by the elastic bag 18, and the ice plug 16 is frozen to generate the ice plug 16. The time to complete is greatly reduced.
[0019]
After the formation of the ice plug 16, as shown in FIG. 3C, the split T-tube 20, the drill holder 30, the jacket 12 having the cooling medium 14, and the cylinder 40 connected to the elastic bag 18 are removed. . Thereafter, the repair / replacement section 44 can be cut without draining the entire piping route. After cutting the repair / exchange section 44, the flange 46 is welded to the cut pipe end.
[0020]
Next, as shown in FIG. 4A, a connection of the gate valve 50 and the drill holder 30 is connected to a T path pipe 48 newly connected to the repair / replacement section 44. After the ice plug 16 is melted, the drill holder 30 and the elastic bag 18 are removed.
[0021]
According to such a method , the volume of the ice plug 16 formed by the action of the cooling medium 14 of the jacket 12 is significantly reduced because the elastic bag 18 is located inside the freezing point and the amount of frozen volume is reduced. Then, since the ice plug 16 naturally arranges the elastic bag 18 in the center of the pipe 10 during the generation process, the hard-to-freeze portion at the center of the pipe is closed by the elastic bag 18, and the inside of the pipe 10 The water is stopped by the built-in ice plug 16. As a result, even when the freezing method is performed by attaching the refrigerant jacket 12 to the outer periphery of the pipe, the water stopping effect can be easily given to the center of the pipe, and the freezing method can be performed even for a large-diameter pipe. Become.
[0022]
FIG. 5A shows a first embodiment of the present invention using an insertion-type freezing promoting jig. This is a preferred example when the repair / replacement unit 44 is located at a position close to the water tank 51. Now, when implementing the ice plug 16 at the broken line position in the figure, a steel ball 56 as an insertion type freezing promoting jig connected with a wire 54 is inserted from the opening 52 of the water tank 51, and Guide to 42. In this manner, similarly to the case where the elastic bag 18 is used, as shown in FIGS. Can be formed.
[0023]
FIG. 6 shows a second embodiment of the present invention . This shows a modification of the insertion type freezing jig. This insertion type freezing promotion jig is installed inside the pipe to reduce the freezing volume inside the pipe, but it also efficiently promotes freezing from inside the pipe. For this purpose, a jig is formed by a hollow container 60 having a hollow portion 58 inside, and this is connected to an external cold and heat source 64 (a cylinder of liquid nitrogen or the like) from the opening of the water tank 51 using a tube 62 instead of a wire. And the jig body also supplies a cold heat source to the freezing section. This embodiment has the effect of shortening the freezing time as compared with the previous example.
[0024]
【The invention's effect】
As described above, according to the pipe freezing method according to the present invention, in a pipe freezing method in which a cooling medium is used to freeze a pipe internal fluid from the pipe surface and the pipe is stopped with an ice plug, an existing pipe communicating with the pipe is used. The insertion type freezing promotion jig inserted from the opening is guided inside the pipe corresponding to the location of the cooling medium, and the jig is frozen for each jig to form an ice plug, so the freezing volume is reduced. The pipes can be stopped in a short time due to freezing, and the repair and replacement of the pipes can be performed in a short time and reliably. In particular, large-diameter pipes that could not be completely frozen in the past In addition, repair and replacement work using an ice plug was made possible.
[Brief description of the drawings]
FIG. 1 is a vertical cross-sectional view showing an arrangement configuration of an elastic bag used in a freezing method according to a conventional technique .
FIG. 2 is an explanatory view showing working steps (first to third steps) of a freezing method according to a conventional technique .
FIG. 3 is an explanatory view showing working steps (fourth to sixth steps) of a freezing method according to a conventional technique .
FIG. 4 is an explanatory view showing working steps (seventh to eighth steps) of a freezing method according to a conventional technique .
FIG. 5 is a work explanatory view using steel balls used in a freezing method according to the first embodiment of the present invention and a vertical and horizontal sectional view showing an arrangement configuration.
FIG. 6 is an operation explanatory view using a hollow container used for a freezing method according to a second embodiment of the present invention, and a cross-sectional configuration diagram of the hollow container.
FIG. 7 is an explanatory diagram of pipe repair.
FIG. 8 is an explanatory sectional view and a perspective view of a conventional freezing method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Piping 12 Jacket 14 Cooling medium 16 Ice plug 18 Elastic bag 20 Split T pipe 22a, 22b Half pipe 24 Branch pipe 26 Handle 28 Valve 29 Flange part 30 Drill holder 32 Flange part 34 Drill insertion hole 36 Drill 37 Electric Drill device 38 Pipe wall hole 40 Cylinder 42 Ice plug implementation position 44 Repair / exchange part 46 Flange 48 T path pipe 50 Gate valve 51 Water tank 52 Tank opening 54 Wire 56 Steel ball 58 Cavity 60 Hollow container 62 Tube 64 Cold heat source

Claims (3)

In a pipe freezing method in which the pipe internal fluid is frozen from the pipe surface using a cooling medium and the pipe is stopped with an ice plug, an insertion-type freezing promoting jig inserted from an existing opening communicating with the pipe is provided with the cooling medium. A pipe freezing method characterized in that the pipe is guided into the inside of a pipe corresponding to a position and is frozen for each jig to form an ice plug. The method according to claim 1, wherein the insertion-type freezing promoting jig is a steel ball. The piping freezing method according to claim 1, wherein the insertion-type freezing promoting jig is formed of a hollow container, and a cooling medium is supplied and filled in the hollow container.

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