JPH03219199A - Thermal insulation device - Google Patents

Abstract

PURPOSE:To shorten a time for a leak fluid to come outside a thermal insulation layer, and enable the early detection of a leak accident by so providing a through-hole on a thermal insulation material covering equipment and piping as to be continuous to the outer surface thereof from the outside. CONSTITUTION:A thermal insulation material 2 is fitted to the outer surface of a pipe 1, and a covering material 3 and sheathing materials 4 and 5 comprising an aluminum foil or the like, are wound around the outside of the material 2. In addition, a through-hole 7 is drilled from the outside to the external surface of the pipe 1. This through-hole 7 is vertically positioned at the bottom side of the pipe 1, reaching the outer surface of the pipe 1 through the sheathing material 4, an air layer a2, the covering material 3, the thermal insulation material 2 and an air layer a1. The diameter of the hole 7 is determined to suit the outer diameter of a thermal insulation layer 6. According to the aforesaid construction, a time for a leak fluid to come outside the thermal insulation layer 6 is shortened and the corresponding early detection of a leak accident becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a heat insulating device for equipment, piping, etc. in a plant such as a power plant.

(Prior Art) The equipment and piping of a power plant are equipped with a heat insulating device coated with a heat insulating material in order to keep the medium sealed inside warm. The insulation structure of this insulation device is as follows: 1. For example, a molded insulation material is attached around the piping, a covering material is wrapped around the insulation material, and an exterior material is wrapped on top of it to protect it. It has become.

In such heat insulation equipment, the heat insulation material has a two-sided structure that connects the pipes from above and below, and the joints are sealed with markings, etc., and the covering material is generally aluminum foil, which is placed on top of the heat insulation material. The seams are simply sealed with adhesive tape or the like, and the exterior material is made from iron plates processed into sheet metal and wrapped around the covering material.

Therefore, in such a heat insulating structure, since the heat insulating material is molded using a mold, an air layer exists between the pipe and the heat insulating material because it does not adhere closely to the surface of the pipe. Also, an air layer is present between the exterior material and the covering material due to poor finishing accuracy.

On the other hand, if a crack or thinning phenomenon occurs in the pipe that penetrates the pipe wall, the fluid inside the pipe leaks and enters the heat insulating layer. This leak fluid first penetrates into the air layer between the pipe and the heat insulating material and is absorbed by the heat insulating material, passing through the joints of the heat insulating material and reaching the covering material. Furthermore, the leaked fluid breaks the seam of the sheathing material, which is a simple seal, and fills the air space between the sheathing material and the exterior material, and then exits from the heat insulating layer through the seam of the exterior material.

(Problem to be solved by the invention) The leakage fluid that has gone out of the heat insulation layer through such a route is
It is only when a patrol inspector discovers that a leak has occurred in the pipes. However, since it takes a long time for the leaked fluid to exit the heat insulating layer after the leak occurs, there are the following disadvantages.

First, if the detection time becomes longer, thinning and cracking of the pipe progresses before the leak is discovered, causing the pipe to rupture all around and increasing the damage caused by the accident. Second, when a large amount of the internal fluid of the leaked pipe permeates into the heat insulating material, harmful corrosive components such as NacQ impregnated in the heat insulating material are eluted and significantly corrode the outer surface of the pipe. The longer it takes for the leak to be discovered, the greater the depth and range of this corrosion, and the more damage it causes.

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat insulating device that shortens the time for leak fluid to exit the heat insulating layer and enables early detection of leak accidents.

[Structure of the invention]

(Means for Solving the Problems) The heat retaining device of the present invention is characterized in that a through hole communicating from the outside to the outer surface of the equipment and piping is provided in the heat insulating material that covers the equipment and piping. be.

(Function) In the present invention, when a leakage accident occurs in one piece of equipment or piping, the leaked fluid penetrates the heat insulating material, coating material, and exterior material, and then fills each air layer and then flows through the through hole into the heat insulating layer. flows outside. Therefore, it becomes easier for patrol inspectors to discover leakage fluid.

It becomes possible to quickly take emergency measures against leaks.

(Embodiments) The present invention will be described below with reference to embodiments shown in the drawings. In FIGS. 1 and 2 showing the heat retention device for tube 1, tube 1
A two-part heat insulating material 2 is attached to the outer surface of the insulation material 2, and the upper and lower seams 2x are simply filled with a joint material such as rock wool. This heat insulating material 2 is usually molded using a mold and does not adhere closely to the outer surface of the tube 1, so that an air layer a1 exists between the tube 1 and the heat insulating material 2 as shown in FIG. become.

Furthermore, a covering material 3 such as aluminum foil is wrapped around the outer surface of the heat insulating material 2, and exterior materials 4 and 5 are wrapped around it for decorative protection. Seam 3x of the covering material 3, 3
are simply sealed with connecting tape, etc., and the exterior materials 4 and 5
Seams 4x and 5x have a general seal structure. Since the exterior material 4 is made from sheet metal processed iron plate and wrapped around the outer surface of the sheathing material 3, the finishing accuracy is poor and there is a gap between the sheathing material 3 and the exterior material 4 as shown in FIG. Also, an air layer a2 is present.

In the present invention, the heat insulating material 2 provided on the outer surface of the pipe 1
This is characterized in that a through hole 7 communicating with the outer surface of the tube 1 from the outside is provided in the heat insulating layer 6 made of the covering material 3 and the exterior material 4. When the piping system is long, the through holes 7 are provided at multiple locations at appropriate intervals, and the direction of the through holes 7 is as shown in FIG. It is a downward hole that reaches the outer surface of the pipe 1 through the covering material 3 - heat insulating material 2 - air layer a, and the diameter of the hole is appropriately set according to the outer diameter of the heat insulating layer 6.

Next, the operation of the heat retaining device of the present invention configured as described above will be explained. Normally, the internal fluid of the tube 1 is effectively kept warm by a heat insulating layer 6 consisting of a heat insulating material 2, a covering material 3, and an exterior material 4. However, if the pipe 1 cracks at a certain point and the internal fluid leaks due to thinning, the leaked fluid moves along the outer surface of the pipe 1 through the air layer a□ while being partially absorbed by the heat insulating material 2. . When the leak fluid reaches the through hole 7,
It runs down the hole wall of the heat insulating material 2 all at once and is discharged out of the heat insulating layer 6 through the hole 7 in the exterior material 4.

Also, the reason why the through holes 7 are provided on the bottom side of the heat insulating layer 6 will be explained. The first is that leakage fluid collects on the bottom side of the tube 1. Not only when the leak fluid is a liquid but also when it is steam, the amount of leak steam at the beginning of the leak is very small, so most of the leak steam is cooled by the heat insulating material 2, etc., and becomes condensed, and the bottom surface of the heat insulating material 2. This takes advantage of the fact that people gather around each other.

The second reason is that, on the contrary, if the through holes 7 are provided on the upper surface side, it is not preferable for rainwater or falling foreign matter to enter the heat insulating layer 6 through the through holes 7. Furthermore, as shown in FIG. 2, the hole diameter φ4 of the exterior material 4 is made smaller than the hole diameter φ2 of the heat insulating material 2 and the hole diameter φ1 of the covering material 3. This is to prevent rainwater from penetrating into the heat insulating layer 6 due to capillary action when it runs down the exterior material 4.

In this way, in the present invention, by providing the through holes 7 in the heat insulating layer 6 of the tube 1, the time required for leakage fluid to exit the heat insulating layer 6 using the through holes 7 in the tube 1 can be effectively shortened. .

This is useful for early detection of leakage accidents in the pipe 1 by patrol inspectors. Furthermore, when the piping system of the pipe 1 is installed with a slope, the leak fluid reaches the through hole 7 quickly, so that the time from the occurrence of the leak to the discharge of the leak fluid to the outside of the heat insulating layer 6 is further shortened.

Next, other embodiments shown in FIGS. 3 and 4 will be described. In this embodiment, compressed air is introduced into the heat retaining layer 6 of the tube 1. That is, as shown in FIG. 3, an air injection bed 8 and an air injection pipe 9 are provided using through holes 7 provided in the heat insulating layer 6.

As shown in detail in FIG. 4, an air injection bed 8 is inserted into the through hole 7 of the heat insulating layer 6 and fixed to the outer surface of the tube 1 by welding 10. The air injection bed 8 is also provided with an air outlet 11 that communicates with the through hole 7 . An air injection pipe 9 is inserted from the hole in the outer cover material 4 of the heat insulation layer 6 of this air injection floor 8 to the end.
are connected by welding 10, and the gap between them and the outer covering material 4 is also welded lO.
closed and sealed.

In FIGS. 3 and 4, compressed air sent from the air injection pipe 9 passes through the air injection bed 8 and is ejected from the air outlet 11 into the through hole 7. The compressed air that has entered the heat insulating layer 6 is pumped along the heat insulating layer 6 of the pipe 1 and
It is discharged to the outside through through holes 7 provided at appropriate intervals.

Therefore, if a leakage accident occurs in the middle of the pipe 1, the leakage body 48 is carried along with the flow of compressed air, so it quickly reaches the through hole 7 near the heat insulating layer 7 and is discharged.

Therefore, this is useful for early complete repair in case of pipe 1 leakage accident. In addition, when compressed air is injected, the internal pressure of the heat insulating layer 6 becomes higher than atmospheric pressure, so if the pipe 1 is an outdoor pipe, the seals at the joints 4x and 5x of the exterior materials 4 and 5 shown in Fig. 1 may deteriorate. Even if the sealing force is lost, rainwater can be prevented from entering into the heat insulating layer 6. Furthermore, in the case of the piping system of pipe 1 in a strongly corrosive environment or a highly concentrated radioactive environment, if compressed air is injected into the heat insulating layer 6, the pressure inside the heat insulating layer 6 will be high, so the heat insulating layer will prevent corrosive fluids and radioactivity. 6 can be prevented from entering.

〔Effect of the invention〕

As described above, according to the present invention, by providing a through hole in the heat insulation layer leading from the outside to the outer surface of the internal equipment, pipes, etc.,
This has the advantage that the time it takes for leak fluid to exit the heat insulating layer is shortened, and leak accidents can be discovered early.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the main parts of the heat retaining device of the present invention, FIG. 2 is a sectional view showing an enlarged through hole portion thereof, and FIG. 3 is a side view showing another embodiment of the present invention. FIG. 4 is an enlarged sectional view showing the air injection portion.

Claims (1)

[Claims] A heat retention device characterized by having a through hole that communicates with the outside surface of the equipment and piping from the outside in the insulation material that covers the equipment and piping.