JP4985931B2 - Water leakage detector and piping structure using the detector - Google Patents

Description

  The present invention uses a detection tool for detecting water leakage in a pipe for hot water or the like provided in association with an air conditioner or the like, in particular, a pipe having a heat insulating material such as glass wool on its outer periphery, and the detection tool. It relates to the piping structure.

As water leak detection means, in order to detect water leaks such as tanks and pipes in the drainage station, a water-absorbing coating material that changes its conductivity by absorbing water and a conductive coating material are applied in layers. There has been proposed a method (Patent Document 1) for detecting a water leak by detecting a change in conductivity of a water-absorbing coating material generated at a location where the water leak occurs. In addition, as a method of detecting the occurrence of condensation and water wetting in electronic devices such as temperature / humidity measuring devices and mobile phones, and precision devices, water leak detection tests that apply pigments or chemicals that develop or change color when wet. Paper and the like are known (Patent Documents 2 and 3).
However, any of these detection means is a method in which leaked water directly contacts a test paper or the like, and is not a method of detecting water leaks in a heat retaining pipe having a heat retaining material or a heat insulating material wrapped around the outer periphery. Therefore, there is a demand for means that can be easily used and reliably detect water leakage at the site of piping work such as water supply, hot water supply, and drainage.
JP 7-294367 A Japanese Patent Laid-Open No. 9-5244 JP-A-6-300751

Piping for water supply, hot water supply, drainage, cold water, hot water, etc., the temperature of the fluid flowing in the pipe, for example, hot water is lowered by the temperature of the outside air, and conversely, the temperature of the surroundings is increased by the heat from the pipe. In order to avoid inconvenience such as becoming, a heat insulating material made of glass wool, rock wool or the like is attached to the outer periphery of the tube. This heat insulating material is made into a cylindrical or semi-cylindrical shape that can be divided by glass wool or the like, and there is also a heat insulating material whose outer periphery is covered with a cover material such as aluminum foil or glass cloth.
For example, in the construction of water distribution pipes, when heat insulation is applied to piping, the heat insulation construction is usually performed after performing a water leak test on the pipe, but when the test is difficult to perform or the test is conducted after a while In such cases, heat insulation work is performed before the water leak test.

Water leakage after the heat insulation work cannot be easily detected by visual inspection from the outside because of the heat insulation material, and the leaked water flows along the heat insulation material and is away from the water leakage location of the piping. There may be water leakage. For this reason, if there is a water leak in the heat-insulated piping, it is necessary to remove all of the heat-insulating material in the vicinity.
The present invention provides a means capable of properly detecting a water leaking part of a pipe after heat insulation without removing unnecessary heat insulation.

In order to solve the above problem, the water leakage detection tool of the present invention includes a stab pin that doubles as a stabbed heat insulator and a water guide, a hygroscopic discolored paper provided on the top of the stab pin, and, if necessary, And a transparent resin sheet or a transparent plastic sheet such as polyvinyl chloride provided on the discolored paper surface. In the case of a horizontal pipe that is piped in a horizontal direction, the water leakage detection tool of the present invention (water leakage detection pin: hereinafter also referred to simply as a detection pin) is inserted into the heat insulating material from the lower surface of the place where water leakage is expected. Used in.
Further, the present invention provides a non-water-permeable heat insulating material between a heat insulating material and a heat insulating material below a portion where water leakage is expected, such as a jointed portion of the pipe, when the pipe to be heat-insulated is in the vertical direction (soot pipe). The present invention relates to a water leak detection piping structure in which a water stop material composed of, for example, is mounted and a detection pin is disposed above the water stop material.

In the present invention, just by inserting the detection pin of the present invention into the joint part of the pipe where water leakage of the heat-insulated pipe is expected, when the water leaks, the leaked water is transmitted through the insertion pin Since the discolored paper at the top of the pin is wetted and discolored, it is possible to easily detect a water leak location.
According to the present invention, the detection pin can be easily mounted simply by being inserted from the surface of the heat insulating material, and since the inspection only looks at the color change of the discolored paper, there is no misunderstanding and can be easily removed after the inspection. Moreover, since the insertion pin is also a thin needle, it has many advantages such as not detracting from the heat retaining effect.

The insertion pin of the detection pin of the present invention may consist of a single pin having a push-in portion at the top like a thumbtack, or an inverted U-shaped U-shape in which two long pins are broken. It may be a nail. Although the length of a pin is not specifically limited, It is set as the length which reaches the inside of a heat insulating material through a cover material. The insertion pin is usually made of metal like a needle or a nail, but may be made of plastic.
As the color-changing paper, a surface of the paper or the paper itself is coated or impregnated with a color material that dissolves when wet or dissolves in water. As a method of color change, for example, a color change method in which a yellow colored paper and a red colored paper are overlapped, and the red pigment on the lower paper melts by being wetted with water, so that the upper yellow paper is changed to red Alternatively, a method may be used in which the color material applied in a dotted manner on the paper surface is dissolved in water and the entire paper surface is colored. As the color material, a color material that changes color or develops color by reaction with water, a color material that becomes a fluorescent color, or any other color material can be used. The discolored paper is preferably moisture absorbing or water absorbing.

The discolored paper is preferably provided in a form where the insertion pin is pierced so that it can easily come into contact with moisture transmitted through the insertion pin. If a transparent resin sheet or a transparent plastic sheet or film (hereinafter referred to as a resin sheet) is provided on the upper surface of the color-changing paper, in order to avoid discoloration due to moisture in the atmosphere or moisture adhering at the time of wearing. good.
The transparent resin sheet may be formed by directly applying a resin liquid on the surface of the color changing paper to form a resin film, or simply overlaying a plastic film such as polyethylene, polypropylene, polyvinyl chloride (vinyl chloride) on the color changing paper or an adhesive. You may provide by the method of laminating | stacking via. In the case of a plastic film, the adhesive is applied to the lower surface as an area larger than the discolored paper, covering the top part of the piercing pin, and the heat insulating material with the adhesive overhanging the area of the discolored paper You may make it adhere | attach on the surface of this.
The detection pin of the present invention can be used in a form in which a transparent resin sheet is not provided.

Examples of the present invention will be described below with reference to the drawings. However, the present invention is not limited to these examples.
FIG. 1 is a side view showing an embodiment of a water leakage detection pin according to the present invention, wherein 1 is a detection pin, 2 is a U-shaped nail insertion pin, 3a is yellow discolored paper, 3b is red discolored paper, 4 Indicates a transparent resin sheet, and 5 indicates a sealing agent for sealing the top of the insertion pin 2. As shown in the figure, the color changing papers 3a and 3b and the transparent resin sheet 4 are integrated by being pierced with the piercing pin 2 in an overlapped state, and in order to prevent moisture from entering from the through hole of the piercing pin 2, Sealing agent 5 is applied to the head.
In addition, when the piercing pin 2 is penetrated only through the color changing paper 3 and the transparent resin sheet 4 is covered on the upper surface of the color changing paper 3 including the top of the piercing pin 2 separately from the present embodiment, the sealing agent 5 is used. Is unnecessary.

FIG. 2 is a plan view showing an example of the color change of the color change paper 3. The color change papers 3a and 3b are both dyed with a pigment that dissolves in water, and when not used (in a dry state), When yellow is visible (FIG. 2A) and the red color changing paper 3b on the lower surface gets wet with water, the red pigment dissolves and shifts to the yellow color changing paper 3a, and the yellow color changing paper 3a turns red (FIG. 2B). ). It is detected that there is water leakage by this color change.
In the case of this embodiment, the yellow discolored paper can be used as long as it is not colored with a water-soluble dye, but can be changed to red upon receiving the transfer of the red dye. Yellow and red are used because they are easily visible to the eyes, but other colors are of course acceptable.

FIG. 3 shows another example of the laminated structure of the color changing paper, and shows a state in which the transparent resin sheet 4 and the color changing papers 3a and 3b are laminated using the double-sided adhesive tape 6 to form the color changing laminated body 7. In the case of this example, the double-sided pressure-sensitive adhesive tape 6 is used for lamination, but it may be laminated using an adhesive or a pressure-sensitive adhesive. When the color-changing paper 3 has two upper and lower sheets, the transparent resin sheet 4 may be a transparent resin sheet (adhesive sheet) in which an adhesive is applied to the entire lower surface. When there is an adhesive surface of the adhesive tape 6 on the lower surface of the resin sheet 4 protruding on the outer periphery of the color changing paper 3, the release paper (release paper) 8 a covering only this adhesive surface or the entire lower surface of the color changing laminate 7 is covered. It is preferable that the release paper 8 to be covered is bonded and peeled off during use.
The color-changing paper 3 or the color-changing laminated body 7 and the insertion pin 2 do not necessarily have to be assembled together, and may be supplied separately and assembled at the time of use.

FIG. 4 is an explanatory view showing a method of using the detection pin of the present invention, and shows an example of construction of a horizontal draw pipe. As shown in the figure, the pipe 10 and the pipe 10 are connected by a joint 11 to cover the pipe with a required length, and the pipe 10 and the joint 11 are covered with a heat insulating material 12. Usually, a pressurized water leakage test is performed after piping to check the presence or absence of water leakage between the pipe 10 and the joint 11. After the coating with the heat insulating material 12, the position of the joint 11 becomes unclear, Due to the material 12, the leakage state cannot be visually observed.
The water leakage detection pin of the present invention is attached by inserting the detection pin 1 at positions corresponding to both ends of the joint 11 of the heat insulating material 12 when the heat insulating material 12 is applied to the joint 11 portion. As shown in FIG. 5, the water leakage from the pipe flows through the heat insulating material 12 to the lower side thereof, so that the detection pin 1 is attached to the lower side of the pipe. If the transparent resin sheet 4 of the detection pin 1 is attached so as to be in close contact with the surface covering material 13 of the heat insulating material 12, it is preferable because the leaked water does not drip down the pipe. In the figure, reference numeral 14 denotes a protective material such as a wire mesh wound around the outer periphery of the heat insulating material.
After the pressure leak test, the presence or absence of discoloration of the detection pin is confirmed, and the heat insulating material in the discolored portion is removed to obtain a good connection state. In this example, the case of a joint has been described, but the same applies to the case of a valve or the like.

  6 and 7 are explanatory diagrams showing a method of applying the water leakage detection pin to the pipe in the vertical direction. In the case of the construction of the soot pipe, in FIG. 6, since the water leakage from the T-shaped joint 11a flows downward along the outer peripheral surface of the pipe 10, it cannot be detected simply by inserting the detection pin 1 near the joint 11a. There is a case. In the present invention, the water stop material 15 is interposed between the heat insulating material 12 at a downstream position of the joint 11a or the like where water leakage is expected, and the heat insulating material above it, preferably at a position close to the upper surface of the water stop material 15. The detection pin 1 is inserted. The leaked water accumulates on the water stop material 15 and is guided by the piercing pin 2 to wet the discolored paper 3 and discolor the detection pin 1. As shown in FIG. 6, water leakage can be detected in the same manner in the case of the elbow joint 11b and the valve 16. As shown in FIG. 7, a caulking agent 17 may be applied to the contact portion with the pipe 10 on the upper surface of the water stop plate 15 as required.

  The water-stopping material is a resin sheet on the end surface of a closed-cell plastic foam molded into a hollow disk that can be divided at an appropriate thickness, such as a heat insulating material such as urethane foam, or a molded product of glass wool or rock wool. You can use the one that has been pasted. In addition, when a conventional heat insulating material is applied, an adhesive plastic sheet may be adhered to the upper end surface of the downstream heat insulating material as a water stopping material, or a plastic sheet having an appropriate thickness may be attached. May be interposed.

  The detection pin of the present invention may be a transparent plate made of hard plastic such as polyvinyl chloride or polystyrene instead of the soft transparent resin sheet 4 of FIG. 1, and this transparent plate is inserted into the transparent plate like a thumbtack. The pin may be integrated. In this case, a discolored paper can be supplied separately and the transparent plate-like body with a stab pin can be used repeatedly.

It is sectional drawing which shows one Example of the detection pin of this invention. It is explanatory drawing which showed the coloring method of the detection pin of FIG. It is a cross-sectional schematic diagram which shows the other example of lamination | stacking of the discoloration paper of a detection pin. It is a perspective view which shows an example of the usage method of a detection pin. It is explanatory drawing of the detection method of a detection pin. It is a cross-sectional schematic diagram which shows the example of application to the construction of the soot pipe of a detection pin. It is a cross-sectional schematic diagram which shows the other example of application of a detection pin.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Detection pin 2 Insertion pin 3 Color changing paper 4 Transparent resin sheet 10 Pipe 11 Joint 15 Water stop material

Claims (4)

When performing piping and heat insulation work in the vertical direction, a water insulation material is installed between the heat insulation material and the heat insulation material below the place where water leakage is expected, such as the joint part of the pipe, and the heat insulation material above this water insulation material. In addition, a water leakage detector consisting of a stab pin serving both as a stab and a water guide and a hygroscopic discoloration paper provided at the top of the stab pin is inserted into the heat insulation material after the heat insulation work. A water leak detection piping structure that can detect a water leak. The water leakage detection tool is a stab pin that stabs a heat insulating material and conducts water, a hygroscopic color change paper provided on the top of the stake pin, and a transparent resin sheet or a transparent plastic sheet provided on the color change paper surface. The water leak detection piping structure according to claim 1, comprising: The color change paper of the water leakage detector is composed of two upper and lower papers. When the lower paper colored with a water-soluble color material gets wet with water, the color material dissolves and shifts to the upper paper. The water leakage detection piping structure according to claim 1, wherein the color of the water leakage is changed. When piping horizontally and performing heat insulation , the insulation material below the place where water leakage is expected, such as the joint part of the pipe, and the insertion pin that combines the penetration of the insulation material and the water conduction A method for detecting a water leakage portion of a pipe after heat insulation construction, wherein a water leakage detection tool comprising hygroscopic color-changing paper provided at a top portion is inserted.

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