JPH062193U - Airtightness monitoring device for wire penetration - Google Patents

Abstract

(57) [Abstract] [Purpose] Even if the pressure of the gas enclosed in the wire penetration changes due to temperature changes in the surrounding environment, it is not mistaken for poor airtightness, and the wire penetration is airtightly provided on the shielding wall. Accurately detect the airtightness of. The airtight wall 20 includes two wall portions 20 that are airtightly installed in the tube 16 with a space in the axial direction of the tube 16.
It consists of A and 20B. These two wall parts 20A, 20B
A gas filling chamber 24 is formed between them. The gas filling chamber 24 has two gas filling chambers 24A,
It is divided into 24B. These two gas filling chambers 24A, 2
The gas 26 is filled in 4B at the same pressure. Gas 2 enclosed in these two gas-filled chambers 24A, 24B
The differential pressure of 6 is measured by the differential pressure gauge 32.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of an airtightness monitoring device for an electric wire penetration portion through which an electric wire penetrates a radiation shielding wall such as a reactor containment vessel and a radioactive waste storage room.

[0002]

[Prior art]

 Generally, when passing an electric wire through a reactor containment vessel, a radioactive waste storage room, etc., a container or a part that needs to be hermetically sealed, the wire penetration is hermetically sealed to the shielding wall to prevent leakage of internal radiation. It is provided in. As shown in FIGS. 5 and 6, the wire penetrating portion is generally provided with a cylinder 16 penetrating through the shielding wall 14 for accommodating the electric conductor 18, and the electric conductor 18 penetrates the inside of the cylinder 16 in an airtight manner. As described above, the airtight wall 20 provided in the cylinder 16 is used. To monitor whether the airtightness of the wire penetration portion 10 is broken, the airtight wall 20 of the wire penetration portion 10 is It is formed from two wall portions 20A, 20B that form a gas filled chamber 24 that extends over the inside and the outside of the electrical conductor 18 and is attached at intervals in the axial direction of the cylinder 16, and is attached to the gas filled chamber 24 in an airtight manner. The airtightness monitoring device 12 including a pressure gauge 40 for measuring the pressure of the gas 26 enclosed in the gas filling chamber 24 may be provided.

The airtightness monitoring device 12 of the wire penetration portion 10 according to the related art includes either the electric conductor 18 and the airtight wall 20, the tube 16 and the airtight wall 20, or the tube 16 and the airtight wall 20. Pay attention to the fact that when a part with poor airtightness occurs in a place, the gas in the gas filling chamber leaks to the outside from that part, or the external atmosphere enters the gas filling chamber and the gas pressure in the gas filling chamber changes. The airtightness is detected by measuring the pressure of the gas in the gas filling chamber with a pressure gauge.

[0004]

[Problems to be solved by the device]

 However, the pressure of the gas in the hermetic chamber also changes due to causes other than leakage, that is, changes in the ambient temperature, or changes in the temperature of the wire penetration due to changes in the load flowing through the electric conductor. In the conventional technology, even if the pressure in the airtight chamber changes due to such a temperature change, the indication value of the pressure gauge may change, and it may be mistaken for airtightness.

According to the present invention, in order to avoid the above-mentioned drawbacks, even if the pressure in the airtight chamber changes due to temperature change, it is possible to accurately detect the airtightness without being erroneously recognized as the airtightness. To provide an airtight monitoring device.

[0006]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention is provided with a cylinder that is hermetically penetrated through a shielding wall to accommodate an electric conductor, and a cylinder provided so that the electric conductor is hermetically penetrated inside the cylinder. The airtight wall of the wire penetration part consisting of the airtight wall and the airtight wall consists of two wall parts that are installed at intervals in the axial direction of the cylinder and that form a gas filled chamber across the inside and outside of the electrical conductor. In the airtightness monitoring device for the wire penetration part consisting of a measuring instrument that measures the pressure of the gas filled in the filling chamber, the gas filling chamber is divided into two gas filling chamber parts by the dividing wall, and the measuring instrument is The present invention provides an airtightness monitoring device for a wire penetrating portion, characterized by comprising a differential pressure gauge connected to the chamber portion and measuring the differential pressure of gas filled in two gas filled chamber portions at the same pressure. .

[0007]

[Action]

 In this way, by dividing the gas-filled chamber into two, filling the two gas-filled chambers with gas at the same pressure, and installing a differential pressure gauge to measure the differential pressure, the pressure of the gas changes due to temperature changes. If changes occur, the pressure in the two airtight chambers changes to the same value, so that no pressure difference is generated and the indicated value of the differential pressure gauge does not fluctuate. When the pressure changes due to gas leakage, the pressure in only the gas-filled chamber where the leakage changes changes and a differential pressure is generated.By measuring this differential pressure, the airtightness can be accurately determined. Can be detected.

[0008]

Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an airtightness monitoring device 12 for a wire penetrating portion 10 of the present invention. A cylinder 16 provided penetratingly, an electric conductor 18 housed in the cylinder 16 and penetrating the shielding wall 14, and an electric conductor 18 in the cylinder 16 provided in the cylinder 16 so as to penetrate in an airtight manner. It consists of a closed airtight wall 20.

The shield wall 14 is used as a wall of a reactor containment vessel, a radioactive waste storage room, and the like (not shown), and seals the radiation and the like enclosed in these vessels and the room. Therefore, it is formed of a material that is impermeable to radiation or the like.

As shown in FIG. 1, the cylinder 16 penetrates the shielding wall 14 in an airtight manner, and penetrates the shielding wall 14 with an electric conductor 18 housed therein. As shown in FIG. 1, a cable 22 is connected to both ends of the electric conductor 18 to electrically connect the inside and outside of the shield wall 14 to each other.

The airtight wall 20 is airtightly attached to the inside of the cylinder 16 so as to prevent radiation and the like in the shield wall 14 from leaking through the wire penetration portion 10. The airtight wall 20 is, as shown in FIG. It comprises two wall portions 20A, 20B mounted axially of the barrel 16 at a distance. As shown in FIG. 2, these two wall portions 20A and 20B are airtightly provided in the cylinder 16 by having their outer peripheral surfaces airtightly attached to the inner peripheral surface of the cylinder 16. Further, the electric conductor 18 penetrates the two wall portions 20A and 20B in an airtight manner, and the gas filled chamber 24 is formed across the inside and outside of the electric conductor 18 by the two wall portions 20A and 20B. To be done.

The airtightness monitoring device 12 of the wire penetration portion 10 measures the pressure of the airtight filling chamber 24 formed in this way and the gas 26 in the airtight filling chamber 24 that is airtightly attached to the airtight filling chamber 24. It consists of a measuring instrument 30. As shown in FIGS. 1 and 2, the gas filling chamber 22 is divided by a dividing wall 28 into two gas filling chamber portions 24A and 24B. In the embodiment of FIGS. 1 and 2, the dividing wall 28 is arranged in the horizontal direction of the cylinder 16 so as to divide the gas filling chamber 24 into upper and lower parts, and is hermetically sealed to the two wall portions 20A and 20B. Mounted. Therefore, the two gas filling chambers 24A and 24B are hermetically sealed and mutually airtight.

The gas 26 is enclosed in the two gas-filled chambers 24A and 24B, but the gas 26 is preliminarily set so that a pressure difference is not generated between the two gas-filled chambers 24A and 24B. The filling chambers 24A and 24B are filled with the same pressure. Therefore, even if the temperature of the wire penetration portion 10 changes due to the ambient temperature change or the load change of the electric conductor 18, the gas pressures in the two gas filling chambers 24A and 24B both change to the same value. Therefore, there is no difference in the pressure of the gas 26 enclosed between the two gas-filled chambers 24A and 24B.

Further, the gas 26 is previously filled in the two gas filling chambers 24A and 24B at a pressure higher or lower than the atmospheric pressure of the surrounding atmosphere. Therefore, when airtightness occurs, the gas 26 flows out, or the surrounding atmosphere flows into the gas filling chamber 24, and the pressure of the gas 26 in the gas filling chamber 24 changes. In particular, if the airtightness of one of the gas filling chambers 24 is poor, the change in the pressure due to the airtightness causes the gas 26 in the two gas filling chambers 24, which have been sealed at the same pressure in advance, to flow. There will be a difference in pressure.

In the present invention, the measuring instrument 30 is composed of a differential pressure gauge 32. As shown in FIGS. 1 and 2, the differential pressure gauge 32 is provided with a pipe hole provided in each of the two airtight filling chambers 24A, 24B. It is airtightly connected to the two gas filling chambers 24A and 24B via a pipe 36 connected to 34. Therefore, the differential pressure gauge 32 can measure the differential pressure of the gas 26 enclosed in the two gas filling chambers 24A and 24B at the same pressure.

Next, the use state of the present invention will be described. The airtightness of the wire penetration portion 10 is monitored by visually confirming the indicated value of the differential pressure gauge 32. That is, when there is no airtight portion in the wire penetration portion 10, there is no difference in the pressure of the gas 26 enclosed in the two gas-filled chambers 24A and 24B. By confirming with the differential pressure gauge 32 that no occurrence has occurred, it can be confirmed that the wire penetration portion 10 is airtight. In this case, in particular, even if the pressure of the gas 26 changes due to the temperature change due to the ambient temperature change or the load change of the electric conductor 18, the pressure of the gas sealed in the two gas filling chambers 24A and 24B is Since it changes to the same value, no differential pressure is generated and the indicated value of the differential pressure gauge 32 does not change either. For this reason, a change in the pressure of the gas 26 due to a change in temperature will not be mistaken for airtightness.

On the other hand, if a poorly airtight portion occurs between the electric conductor 18 and the airtight wall 20, between the cylinder 16 and the airtight wall 20, or at any place of the cylinder 16 and the airtight wall 20, that portion is generated. The gas 26 in the gas filling chamber 24 leaks to the outside, or the external atmosphere flows into the gas filling chamber 24, and one of the two gas filling chambers 24A and 24B is filled. The pressure of the gas inside changes. Therefore, the pressure of the gas 26 is different between the two gas-filled chambers 24A and 24B, and the indicated value of the differential pressure gauge 32 is changed, so that the airtightness can be accurately detected.

In the embodiment of FIGS. 1 and 2, the dividing wall 28 is arranged horizontally and the gas filling chamber 24 is divided into upper and lower parts. However, as shown in FIGS. As in the case of the airtight wall 20, the inner peripheral surface of the cylinder 16 may be airtightly engaged and arranged in the vertical direction of the cylinder 16, and the gas filling chamber 24 may be divided into front and rear in the axial direction of the cylinder 16.

[0019]

[Effect of device]

 According to the present invention, as described above, the gas filling chamber is divided into two, the two gas filling chambers are filled with gas at the same pressure, and the differential pressure gauge for measuring the differential pressure is provided. Therefore, if the gas pressure changes due to a temperature change, the pressures of the two hermetic chambers change to the same value, no differential pressure is generated, and the indicated value of the differential pressure gauge does not fluctuate. It is not mistaken as a defect, but only when the pressure changes due to gas leakage, the pressure changes only in the gas-filled chamber where the gas leaks, resulting in a differential pressure. Therefore, there is a merit that the airtightness can be accurately detected.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an airtightness monitoring device for an electric wire penetration portion according to the present invention.

FIG. 2 is a cross-sectional view of an airtightness monitoring device for a wire penetration portion according to the present invention.

FIG. 3 is a vertical cross-sectional view of another embodiment of the airtightness monitoring device for the wire penetration portion of the present invention.

FIG. 4 is a cross-sectional view of another embodiment of the airtightness monitoring device for the wire penetration portion of the present invention.

FIG. 5 is a vertical cross-sectional view of a conventional airtightness monitoring device for a wire penetration portion.

FIG. 6 is a cross-sectional view of a conventional airtightness monitoring device for a wire penetration portion.

[Explanation of symbols]

 10 Wire Penetration Part 12 Airtight Monitoring Device 14 Shielding Wall 16 Tube 18 Electric Conductor 20 Airtight Wall 20A, 20B Two Wall Parts 24 Gas Filling Chambers 24A, 24B Two Gas Filling Chambers 26 Gas 28 Dividing Wall 30 Measuring Instrument 32 Differential Pressure Meter 34 Piping hole 36 Piping

Claims (1)

[Scope of utility model registration request] 1. An electric wire penetration consisting of a cylinder that is hermetically penetrated through a shielding wall for accommodating an electric conductor, and an airtight wall provided in the cylinder so that the electric conductor is hermetically penetrated inside the cylinder. The airtight wall of the section is composed of two wall portions that are mounted at intervals in the axial direction of the cylinder and that extend over the inside and the outside of the electric conductor to form a gas filled chamber, and are enclosed in the gas filled chamber. In an airtightness monitoring device for an electric wire penetration portion including a measuring instrument for measuring gas pressure, the gas filling chamber is divided into two gas filling chamber portions by a dividing wall, and the measuring instrument is
An airtightness monitoring device for a wire penetrating portion, comprising a differential pressure gauge connected to the two gas-filled chamber portions and measuring a differential pressure of gas enclosed in the two gas-filled chamber portions at the same pressure. .