JP3131735B2 - How to check for leakage of cable penetration - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a method for confirming leakage of a wire penetration between rooms that require airtightness, that is, a cable penetration.

[Conventional technology]

As described in Japanese Utility Model Laid-Open No. 55-109898, a conventional apparatus has an airtight chamber provided in the center of a cable penetration section, and applies air pressure to the airtight chamber from the outside of the airtight chamber, and the entire cable penetration section is provided. This is to make it possible to check for leaks.

The airtight chamber is partitioned by the main body of the penetrating portion, the electric cable, and two end plates.
A pressure device (including a pressure gauge) provided on the penetrating portion main body side can apply pressure to the entire airtight chamber to perform the operation.

This conventional example is a method in which leakage is checked collectively for a plurality of cable penetration portions, and the range in which leakage is checked becomes wide. (The pressurized volume increases.) Another conventional example is disclosed in Japanese Patent Application Laid-Open No. 61-273115. It has a sleeve on each cable.

The structure of the airtight chamber is such that a plurality of cable penetration portions are filled with a sealing material to provide an airtight space as in the conventional device, and the method of checking leakage is performed by using a leak check nozzle provided outside the airtight chamber. This is a method in which a plurality of cable penetration portions are collectively checked at a time by applying more air pressure. Also in this conventional example, the pressure range is wide because the pressurization range is the entire cable penetrating portion.

[Problems to be solved by the invention]

The above prior arts are designed so that leak checking can be performed collectively for a plurality of cable penetrations.However, since the pressure range of the airtight chamber is wide, when checking for leaks, There is a possibility that the sealing pressure of the hermetic chamber may change due to the fluctuation of the ambient temperature or the like, so it is necessary to confirm the leakage at a relatively high pressure that is not affected by the fluctuation of the ambient temperature.

In addition, if leakage occurs in the airtight chamber, it is difficult to identify (determine the position) of the leaking cable penetrating portion. There is a disadvantage that the repair work becomes extremely large because the method is either a method of filling and repairing the entirety of the cable penetration portion from the outside with a sealing material.

An object of the present invention is to make it possible to confirm leakage of an airtight chamber seal portion independently for each of a plurality of cable penetration portions or for each of a plurality of cable penetration portions in order to compensate for the disadvantages of the above-described conventional technology. It is another object of the present invention to provide a method for confirming a leakage of a cable penetration, which is capable of repairing a seal portion only at a cable penetrating portion where the leakage has occurred even when a leakage occurs.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a cable that penetrates an airtight wall, and a cable that is provided airtight at a penetrating end of the wall, a tip portion is formed at an open end, and the cable penetrates the inside of the cable one by one. When confirming leakage from the sealing material of a cable penetration comprising a cylindrical sleeve that has been filled, and a sealing material that is filled in the base end portion of the sleeve and seals between the cable and the sleeve, A jig for closing the open end is attached, a gap formed in the sleeve at the tip side from the sealing material is made airtight, and a pressurized gas is sealed in the gap to check for leakage of each sleeve. This is a method for confirming the leakage of the cable penetration performed every time. Here, a plurality of cables may penetrate the sleeve in addition to the case where the cables penetrate one by one. Further, when leakage from the sealing material is confirmed, the gap is filled with the sealing material via the opening end.

Furthermore, the above-mentioned leak check jig has a two-part structure so that the cable wire can be sandwiched, and an O-ring is attached to the seal between the leak check sleeve and the cable wire to maintain airtightness. What you can do is better. Further, it is preferable that the leak check jig is provided with a leak check nozzle so as to be pressurized from the outside.

[Action]

According to the above configuration, a jig is attached to the opening end of the sleeve tip to make the gap in the sleeve airtight, and pressurized gas is sealed in the airtight gap to check leakage from the seal. Work can be done. When the leak checking operation is completed, the jig is removed from the open end of the sleeve tip. If leakage from the seal portion is confirmed, the repair work can be easily performed by filling the seal material through the open end.

Further, in the cable penetration according to the present invention, when a jig is attached to the opening end of the sleeve distal end portion, the air gap forms an airtight chamber, and this airtight chamber can be made extremely small as compared with the prior art.

As a result, the sealing pressure in the hermetic chamber is hardly affected by changes in the ambient temperature, and even in the event that a leak occurs in the hermetic seal portion, the sealing material can be repaired for each cable or for each unit. It becomes possible.

In this case, the method of attaching the leakage checking sleeve to the end plate of the cable penetrating portion includes welding, screwing, and the like.

By filling the above-mentioned leak confirmation sleeve with a fixture and a sealing material for mechanically fixing the cable, there is a function of forming an airtight seal portion of the cable penetration portion.

At the extended end of the leak checking sleeve, a leak checking jig that fixes the cable wire and the leak checking sleeve at the same time is attached, and has the function of performing leak checking when necessary. I have.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows the entire structure of a cable penetration having a radiation shielding function when an embodiment of the present invention is employed. The plurality of penetrating cables 1 penetrate through the penetrating cable container 2 incorporated in the airtight wall 3, and are taken out of the airtight wall 3 to the outside of the container 2.

A radiation shielding material 4 having a shielding function equivalent to that of the airtight wall 3 is filled between the through cables 1 in the through cable storage container 2. An airtight seal between the rooms partitioned by the airtight wall 3 is formed by providing an airtight seal portion 6 at a cable penetration portion of an end plate 5 provided outside the radiation shielding member 4.

This hermetic seal portion 6 is provided with a leakage confirmation sleeve 7 in which the through cable 1 is disposed at the center and which is attached to the end plate 5 by welding.
The fixture 8 of the through cable 1 is attached between the two to restrain the axial movement of the through cable 1. The sealing structure of the hermetic seal portion 6 is such that a sealing material 9 is filled between the leak confirmation sleeve 7 and the through cable 1 for sealing. The filling of the sealing material 9 is performed by using an injection jig (not shown) such as an injection needle from the leakage confirmation sleeve 7 extended outside the protective cover 10. The leak confirmation sleeve 7, the fixing metal member 8, and the sealing material 9 are attached to all the through cables 1 in the above structure.

FIG. 2 shows an embodiment of the present invention shown in FIG.
3 shows a configuration for checking leakage of the hermetic seal portion 6.

A leak checking jig 11 is attached to the outside of the leak checking sleeve 7 so as to sandwich the through cable 1, and a pressurizing device 12 for pressurizing a part of the jig 11 is provided. The leak check jig 11 has a split structure as shown in FIG.
Since it is a pressing jig, it is sealed with an O-ring 13.

The method of confirming the leakage is as follows.
As shown in the drawing, the pressure is sealed in the hermetic chamber 14 which is the cavity of the cylindrical sleeve 7 with the pressurized gas. In this case, since the volume of the airtight chamber 14 is small, the leakage can be confirmed at a relatively low pressure without being affected by the fluctuation of the ambient temperature.

If a leak is found in the seal portion 6 in the hermetic chamber 14, the leak check jig 11 is removed, a repair seal material 15 is additionally filled from the end of the sleeve 7, and the leak check is performed again. Become.

 According to this embodiment, the following effects can be obtained.

(1) Leakage of multiple cable penetrations can be checked for each cable individually, so even if a leak should occur, repair work is limited to the penetration and the workability is greatly improved. improves.

Further, as shown in FIG. 2 of this embodiment, by extending the leakage confirmation sleeve, there is an effect that the repair seal material can be filled several times.

(2) Further, since the repair range can be limited, the filling amount of the sealing machine for the repair can be greatly reduced, and the economic efficiency is improved.

(3) Since the airtight chamber at the cable penetration portion can be made extremely small, the sealing pressure of the airtight chamber is not affected by fluctuations in the ambient temperature, and leakage can be confirmed even under relatively low pressure.

In the above embodiment, the case where one cable is used and one sleeve is described as an example. However, the same operation and effect can be obtained even when a plurality of cables are used as a unit and this penetrates one sleeve. can get. That is, leakage can be confirmed for each of a plurality of cables.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION Since this invention can comprise an airtight chamber for every one of several cable penetration parts, or for every several cables, it has the effect as described below.

(1) Leakage of multiple cable penetrations can be checked for each cable or for multiple cables, so even if a leak should occur, repair work should be performed only on the cable penetrations. Workability is greatly improved.

(2) Also, since the repair range can be limited, the amount of sealing material for repair can be greatly reduced, and the economic efficiency can be improved.

(3) Since the airtight chamber at the cable penetration portion can be made extremely small, the sealing pressure of the airtight chamber is not affected by fluctuations in the ambient temperature, and leakage can be confirmed even under relatively low air pressure.

[Brief description of the drawings]

FIG. 1 is a sectional view of a cable penetration showing one embodiment of the present invention, and FIG. 2 is a detailed view taken in the direction of the arrow II in FIG. 1, showing the structure of the hermetic seal portion and leakage of the hermetic seal portion. FIG. 3 is a cross-sectional view showing the configuration, and FIG. 1 ... penetrating cable, 5 ... end plate, 6 ... airtight seal part, 7 ... leak check sleeve, 8 ... fixing bracket, 9 ...
... Seal material, 11 ... Jig for checking leakage, 12 ... Pressurizing device, 13
... O-ring, 14 ... airtight chamber, 15 ... repair seal material.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01M 3/02 G21C 13/036 G21C 17/003 H02G 3/22

Claims (3)

(57) [Claims] 1. A cable which penetrates an airtight wall, and a tubular sleeve which is hermetically provided at a penetrating end of the wall, has a distal end formed at an open end, and the cable penetrates the inside of the cable one by one. A jig for closing the open end when confirming leakage of the cable penetration from the sealing material, the sealing material being filled in a base end portion of the sleeve and sealing between the cable and the sleeve. To make a gap formed in the sleeve on the tip side from the sealing material in an airtight state, fill the gap with a pressurized gas, and perform a leak check of a cable penetration for checking each sleeve individually. Confirmation method. 2. A method according to claim 1, wherein said sleeve penetrates a plurality of cables in addition to a cable penetrating one by one. 3. The method according to claim 1, wherein when leakage from the sealing material is confirmed, the gap is filled with the sealing material via the opening end.