JP3125502B2 - Sealing test method for rubber seams - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airtightness test method for a high-pressure gas storage system, and more particularly to an airtightness test method for a rubber seam capable of non-destructively and easily airtightly testing a seal made of a rubber sheet. It is.

[0002]

2. Description of the Related Art Recently, CAES (Compressed Air Energ
y Storege System (short for energy storage system using high-pressure air) is attracting attention. In CAES, surplus nighttime electric power is stored in place of air compression energy, and the air compression energy is returned to electric power during daytime and used. As a result, the difference in power demand between day and night is averaged, the utilization efficiency of the power generated by the power plant is increased, and the peak of power demand concentrated in daytime is reduced. Specifically, CAES operates a compressor with nighttime electric power to create high-pressure compressed air, stores the high-pressure compressed air, and pays out the high-pressure compressed air the next day, mixes it with fuel gas, burns it, and generates electricity. The gas turbine is designed to run. That is, it is a system that converts the energy of surplus electric power into energy of gas pressure and stores it.

In CAES, an underground is used as a place for storing compressed air. A cavity is formed in the bedrock to serve as a space (storage room) for storing air. Since the surrounding area is rock, a robust storage room that can withstand high pressure can be easily constructed. Furthermore, the use of underground leads to effective use of land above ground.

[0004] Separately, utilization of cavities in underground rock for the purpose of storing fuel gas such as propane and methane has been studied. This system is called a satellite base, and stores fuel gas at high pressure in a storage tank using rock around the city or a storage tank built underground.

[0005] Rocks selected for CAES and satellite bases, of course, have sufficient strength and airtightness, but may have small gaps. Even if it is a small gap, the pressure of the stored gas is 40 to 100 kg / cm ^2.
Because of the high pressure, gas may leak therefrom. In order to prevent this, the storage chamber will be sealed.

[0006] Despite the use of such a solid rock, it is necessary to provide a seal in order to obtain a desired airtightness. The present applicant considers that the airtightness is increased by using a rubber airtight sheet as a sealing material. This can be achieved by joining rubber sheets of an appropriate size and lining the entire surface of the cavity. The rubber sheet is easy to follow even when the cavity has a curved surface when building the storage room, and can be used without being fixed to the cavity. It is not fixed to the cavity because it is supported by the internal pressure of the stored gas even if it is not fixedly supported, and when the pressure becomes high, it can be pressed against the cavity and resist the pressure. In addition, even if the cavity moves due to vibration or the like, there is no breakage. Furthermore, rubber sheets are cheaper than metal materials such as steel, and are easy to carry on site. Since the seam of the rubber sheet may be bonded with an adhesive or the like, the construction is simple.

[0007]

Incidentally, when the above-mentioned seal is applied, it is necessary to perform an inspection such as an airtight test in order to confirm the reliability. In particular, the seam test must always be performed because the seam is bonded on site.

[0008] However, there is no precedent at all in the art of forming a cavity in an underground bedrock and lining the cavity with rubber. For this reason, an inspection method in such a system has not been established. The present applicant considers that it is important to establish an inspection method in order to spread such a system.

[0009] As a condition, first, it is natural that the inspection is nondestructive. For nondestructive inspection, for example, if the inspection target is steel, methods such as X-ray inspection, color check, and acoustic inspection are well known, but none of these methods is suitable for rubber. In addition, it must be possible to inspect from inside the storage room. Because the area around the storage room is rock, inspection from outside is not possible. Since the inspection is performed before the gas is stored, it is preferable that the inspection can be performed under substantially atmospheric pressure. On the other hand, if a reliable rubber sheet is used in advance, the inspection location may be limited mainly to the joint.

As described above, various conditions must be satisfied in order to establish an airtight test method.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide an airtightness test method of a rubber seam which can easily and nondestructively test a seal made of a rubber sheet.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, according to the present invention, rubber sheets are overlapped with each other to form a seam,
After sealing the perforated pipe in the seam and bonding the seam, the rubber sheet and the perforated pipe are joined together and lined in the cavity, and then a test gas is sent into the perforated pipe, and from the seam, It detects whether or not the test gas leaks.

[0013]

With the above arrangement, when the lining is completed, the perforated pipe is confined between the rubber sheets over all the seams. The hole of the perforated pipe is in contact with the rubber sheet from the inside of the seam. When the test gas is fed into the perforated pipe, the test gas flows out of the hole toward the rubber sheet. Because the perforated pipe is confined between the rubber sheets, the test gas does not escape from the seam. If the test gas leaks into the storage chamber, it indicates that the seam is defective.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 2 is a cross-sectional view of a storage room using a rock for CAES, and FIG. 1 is a cross-sectional view showing details of a joint portion of a rubber sheet serving as a seal of the storage room.

As shown in FIG. 2, a cavity 1 is formed in an underground rock. In this embodiment, the cavity 1 is formed in a substantially horizontal and elongated tunnel shape by a shield excavation method or the like. . In order to make this cavity a storage chamber 2 for storing high-pressure gas, a large number of concrete segments 3 of an appropriate size are arranged inside the cavity 1 along the rock. In the cavity 1,
In this way, a storage room 2 surrounded by a concrete wall composed of many segments 3 is formed. In this example,
The storage room 2 has a substantially cylindrical shape, a size of several kilometers in the longitudinal direction, a diameter of several meters, and the like.
It is several hundred meters deeper.

A rubber film 5 is lined along the concrete wall 4 over the entire inside of the storage chamber 2. However, the rubber film 5 is not joined to the concrete wall 4. The rubber film 5 is formed by splicing a large number of fixed-size rubber sheets 6 having a predetermined size, for example, cut into a rectangular shape. The rubber film 5 thus formed constitutes one bag as a whole, and covers the inside of the storage chamber 2. This bag directly serves as a container for storing the stored gas.

As shown in FIG. 1, the seams of the rubber sheets 6 are overlapped with each other, and the seams 7 of the adjacent rubber sheets 6 are overlapped with each other. Glue with adhesive 8. A seam 9 is formed around each rubber sheet 6. The adhesive 8 does not use an organic solvent, for example, a thermosetting adhesive. This is to prevent the volatile gas of the organic solvent from diffusing into the storage chamber 2. The adhesive 8 is injected into the seam 9 or applied to one side or both sides of the seam to be used for bonding, and the adhesive 8 is interposed substantially over the entire surface of the seam 7. Do not use adhesive on the part that touches the opening pipe.

A perforated pipe 10 is sandwiched between the rubber sheet 6 and the seam 9 where the rubber sheet 6 is overlapped during bonding. After the rubber sheet 6 is bonded, the perforated pipe 10 is confined in the bag-shaped seam 9. The perforated pipe 10 has a large number of ventilation holes 11 on the side surface, and is arranged along the seam 9. When many rubber sheets 6 are joined, the perforated pipes 10 are also connected. Since the seam 9 is formed in the longitudinal direction and the circumferential direction of the storage chamber 2, the perforated pipe 10 is also provided in the longitudinal direction and the circumferential direction. In the longitudinal direction, a perforated pipe 10 is connected between both ends of the storage chamber 2 (within a cross section of the rubber film 5 indicated by a solid line). It is formed in an annular shape by making one round in the circumferential direction (within the seam 9 indicated by a broken line). A large number of the perforated pipes 10 in the circumferential direction are arranged at predetermined intervals in the longitudinal direction. A pipe joint or the like is provided at a portion where the perforated pipes 10 intersect, whereby the longitudinal perforated pipe 10 and the circumferential perforated pipe 10 communicate with each other. These many circumferentially perforated pipes 10
Thus, the perforated pipe 10 in the longitudinal direction is laid as if it were a cage. Thus, the rubber film 5 constituting the bag and the perforated pipe network concealed by the joint 9 are formed in the storage chamber 2.

After completion of the lining, an airtight test is performed. An injection port for the test gas is provided at an arbitrary position of the perforated pipe 10, and a test gas supply source placed on the ground or the like is connected to the injection port. When the test gas is supplied from the test gas supply source, the test gas is distributed throughout the perforated pipe 10, and the test gas is supplied from the vent holes 11 of the perforated pipe 10 to the seam 9 of the rubber sheet 6. Come out.

Here, gases such as ammonia, various halogens, and helium are used as the test gas. On the other hand, a gas detection device for detecting the test gas is installed in the storage room.

If the adhesion is normal, the test gas will not escape from the seam. If the test gas leaks into the storage chamber 2, it is known that the seam 9 is defective. By detecting the test gas in the storage chamber 2 in this manner, the quality of the airtightness of the joint of the rubber sheet 6 is detected. In order to identify a defective portion, soap water is applied to the seam 9 and the generation of bubbles due to leak gas is used. If the test gas cannot be used, air may be used. In this case, the detection with the soapy water is performed from the beginning.

In order to efficiently specify a defective portion, inspection may be performed for each span. For example,
Valves and inlets are provided in the perforated pipe 10 at appropriate intervals along the longitudinal direction of the storage chamber 2, and during testing, the valves are opened and closed appropriately or the inlets are changed. .

The present invention also has the effect that the perforated pipe 10 formed in a cage shape is used as the skeleton of the rubber film 6. Since the rubber film 6 is not supported by other structures, it is likely to collapse unless a certain internal pressure is applied. In addition, during the construction of the lining, the shape is not determined because the bag has not yet been formed, and the joining is troublesome. Therefore, a temporary supporting bone is required during the construction, but if the perforated pipe 10 is assembled as a framework and the rubber sheet 6 is stretched between the perforated pipes 10, the lining can be easily performed.

The perforated pipe 10 is left as it is even after the completion of the airtight test after the completion of the lining, and is used for the airtight test at the time of periodic inspection. For this purpose, it is preferable that the pipe diameter is not too large. If the pipe diameter is large,
While filling the storage room with high-pressure compressed air,
This is because the perforated pipe 10 is buckled and crushed by the pressure, and cannot be reused.

On the other hand, if the diameter of the pipe is too small, a pressure loss occurs when the test gas is supplied, so that the airtight test cannot be performed properly. After all, the pipe diameter should be about 3/4 inch, and a perforated pipe made of iron should be used.

[0027]

The present invention exhibits the following excellent effects.

(1) Since only a perforated pipe is inserted in the joint, the structure is simple, does not hinder the operation, and can be used repeatedly.

(2) The airtightness of the seal by the rubber film can be guaranteed, which leads to the promotion of practical use of CAES. It will also provide a standard test method for airtightness in the future.

[Brief description of the drawings]

FIG. 1 is a sectional view of a seam of a rubber sheet showing one embodiment of the present invention.

FIG. 2 is a cross-sectional view of a storage chamber showing one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hollow 5 Rubber film 6 Rubber sheet 9 Seam 10 Perforated pipe

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideyuki Tatsuki 3-2-16-1 Toyosu, Koto-ku, Tokyo Ishikawa-jima-Harima Heavy Industries, Ltd. Toyosu General Office (56) References JP-A-55-48630 A) JP-A-58-221141 (JP, A) Jikken Sho 51-4088 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01M 3/00-3/40 B65D 88 / 76 B65G 5/00 H02J 15/00 JICST file (JOIS)

Claims (1)

(57) [Claims] 1. An airtightness of a rubber seam for inspecting an airtightness of a seam in order to cover a cavity formed in an underground rock with a rubber film spliced with a rubber sheet and store high-pressure gas therein. In the test method, the rubber sheets are overlapped with each other to form a seam, a perforated pipe is sealed in the seam, the seam is adhered, and the rubber sheet and the perforated pipe are sequentially joined and lined in the cavity. An airtightness test method for a rubber seam, comprising feeding a test gas into a perforated pipe and detecting whether the test gas leaks from the seam.