JPH0340050Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a wire penetration device that is installed in a container containing a cryogenic liquid, such as an LNG or LPG storage tank.

[Conventional technology]

A pump is installed inside the container to pump up the liquid from the container containing the cryogenic liquid such as LNG. The electric wire that supplies driving power to this pump is passed through the container in an airtight manner to avoid leakage of gasified LNG, etc. For this reason, wire penetration devices have been conventionally provided, but in conventional devices, a penetration fitting is sandwiched between a pair of flange joints provided in the middle of a wire insertion tube protruding from a container, and the wire is inserted into the penetration fitting. It was made to penetrate airtight.

Conventionally known methods for maintaining airtightness in this case include filling an insulating mixture between the electric wire and the through hole of the through fitting, and interposing a packing on the flange of the insulating cylinder and tightening bolts to the through fitting. There was a method to do so.

[The problem that the idea attempts to solve]

In the penetration part of the above-mentioned electric wire penetration device, there is a large pressure difference (50Kgf/ ^cm2) between the inside and outside of the container.
G) and a large temperature difference (from normal temperature)
(difference with LNG temperature). For this reason, the method of filling with an insulating mixture has the drawback that the amount of filling is large and the overall size of the device is increased. In addition, the method of tightening the packing with bolts can solve the problem of increasing the size, but it can only provide a low airtightness of about 10 ^-4 cc/sec, and furthermore, depending on the tightness of the packing, etc.
The disadvantage is that the airtight performance varies.

Therefore, the purpose of this invention is to improve airtightness without increasing the size of the device.

[Means to solve the problem]

In order to achieve the above object, this invention provides a through hole 2 in the center of the main body fitting 1 made of a metal plate of a required thickness, and also provides a plurality of mounting holes 3 along the outer periphery of the main body fitting 1. A ceramic insulating tube 5 is fitted onto the conductor pull-out rod 4 passed through the through hole 2, both ends of the conductor pull-out rod 4 are exposed from both ends of the insulating tube 5, and the conductor pull-out rod is inserted from the outer peripheral surface of one end of the insulating tube 5. An end fitting 6 is fitted over a range covering the outer peripheral surface of 4, and a silver brazing layer 7 is provided at each fitting portion,
A mounting bracket 8 is fitted in a range extending from the inner circumferential surface of one end of the through hole 2 to the outer circumferential surface of the insulating cylinder 5, a silver brazing layer 9 is provided at the fitting part, and electric wires 10, 10, and insert insulating protective tubes 11, 11 in the range extending from the connecting part to the main body metal fitting 1, and then connect the insulating tube 5 and the protective tube 1.
The structure is such that the gap between 1 and 11 is filled with an insulating mixture 12.

[Effect]

The main body fitting 1 is airtightly installed between flange joints 15 of a wire insertion pipe 14 connected to a container 13 such as a tank. Airtightness between the conductor pull-out rod 4 and the insulating tube 5 is maintained by the silver solder layer 7 of the end fitting 6. Airtightness between the insulating tube 5 and the main body fitting 1 is maintained by the silver solder layer 9 of the mounting fitting 8.

〔Example〕

As shown in the accompanying drawings, the main body fitting 1 is a metal disc, and has a thickness that can withstand the pressure difference between the inside and outside of the container 13 (see FIG. 4). Three through holes 2 are provided in the central portion of the main body fitting 1, and a plurality of attachment holes 3 are provided along the outer periphery of the main body fitting 1. The end of the through hole 2 on the side of the container 13 has a larger diameter.

A conductor pull-out rod 4 is passed through the central portion of the through hole 2 . An insulating tube 5 made of ceramic is fitted around the outer periphery of the conductor pull-out rod 4. Both ends of the conductor pull-out rod 4 are exposed from both ends of the insulating cylinder 5. An end fitting 6 is fitted between the insulating cylinder 5 and the conductor pull-out rod 4. As shown in FIG. 3, the end fitting 6 consists of two end cylindrical portions with different diameters that fit onto the outer circumferential surface of the end of the insulating tube 5 and the outer circumferential surface of the conductor pull-out rod 4, and a central stepped portion that corresponds to the end surface of the insulating tube 5. Become. Gap between end fitting 6 and insulating cylinder 5 and end fitting 6
The gap between the conductor pull-out rod 4 and the conductor pull-out rod 4 are each preliminarily metallized and soldered with silver, and the silver solder layer 7 fixes the gap to maintain airtightness.

In addition, the power supply side end of the through hole 2 of the main body fitting 1,
A mounting bracket 8 is fitted between the outer peripheral surface of the insulating cylinder 5 and the end thereof. The mounting bracket 8 is attached to the through hole 2
It has both end cylinder parts of different diameters and an intermediate stage part that fit into the inner peripheral surface of the insulating cylinder 5 and the central outer peripheral surface of the insulating cylinder 5, and the gaps between these fitting parts are each pre-metalized and then silver soldered. It is fixed by the silver solder layer 9 and kept airtight.

Terminal fittings 16 are fixed to both ends of the conductor pull-out rod 4, respectively, and cable terminals 18 are fastened to each terminal fitting 16 with bolts 19, respectively. The conductor 20 of the electric wire 10 is inserted into the insertion port of each of these cable terminals 18 and integrated by crimping.

The insulating cylinder 5, the conductor pull-out rod 4 exposed from both ends thereof, the terminal fitting 16, and the cable terminal 1
A protective tube 11 made of an insulating material is fitted around the connecting portion between the electric wire 8 and the electric wire 10 at a required interval. The protection tube 11 consists of a large diameter protection tube 11a and a small diameter protection tube 11b. Large diameter protection tube 11 on the power supply side
The inner end of a is tightly fitted inside three guide pins 21 protruding around the power supply side end of the through hole 2 of the main body metal fitting 1. Further, the inner end portion of the large diameter protective tube 11a on the side of the container 13 is fitted into the large diameter portion of the through hole 2. The small diameter protection tube 11b is screwed to the end of the large diameter protection tube 11a.

Between the two large-diameter protection tubes 11a mentioned above, the insulating tube 5 surrounded by them, the ends of the conductor pull-out rod 4 and the terminal fitting 16, and between the through hole 2 of the main body fitting 1 and the insulating tube 5. In between, an insulating compound 12 is filled.

Note that similar airtight penetration devices are provided for the other two through holes 2 of the main body fitting 1.

The device of the embodiment has the above configuration, and each large-diameter protection cylinder 11a is fixedly integrated with the internal insulation cylinder 5 and the like by solidifying the insulating mixture 12. The main body fitting 1 is a flange joint 15 provided in the middle of a wire insertion tube 14 provided in a container 13, as shown in FIG.
It is interposed between the respective flanges, is kept airtight by a packing 22, and is fastened and fixed with bolts and nuts passed through the mounting holes 3. During installation work, prepare the main body metal fitting 1, conductor pull-out rod 4, insulating tube 5, and terminal mounting metal fitting 1.
6. Insulating mixture 12 and both large diameter protective tubes 11a
are assembled together, and the electric wire 10
The cable terminal 18 is crimped to the conductor 20 of the wire 10 in advance, and the small-diameter protection tube 11b is fitted around the electric wire 10. Afterwards, connect cable terminal 1.
8 to the terminal mounting bracket 16 with bolts 19, and connect the inner end of the small diameter protection tube 11b to the large diameter protection tube 11a.
screwed to the outer end of the The electric wire 10 drawn into the container 13 is connected to a suction pump 23 for liquid fuel such as LNG.

In the electric wire penetration device installed in this manner, there are two paths for leakage of gas generated on the side of the container 13: one passing through the inside of the electric wire 10 and one passing through the outside of the electric wire 10.

Passing through the inside of the electric wire 10 occurs when the outer sheath of the electric wire 10 inside the container 13 is damaged, but in this case, the leaked gas passes through the inside of the electric wire 10 and reaches the electrical equipment on the power supply side, so it is safe. It is desirable to maintain a high degree of airtightness. Therefore, in this invention, the electric wire 10 is cut and the conductor pull-out rod 4 is connected to the conductor 20 at the cut end via the cable terminal 18 and the terminal fitting 16, and the conductor pull-out rod 4 and the main body metal fitting 1 are connected. In order to insulate between the conductor pull-out rods 4
An insulating cylinder 5 is fitted in the insulating cylinder 5. Further, the airtightness between one end of the insulating tube 5 and the conductor pull-out rod 4 is ensured by the silver brazing layer 7 formed on the fitting part of the end fitting 6, and the airtightness between the insulating tube 5 and the main body fitting 1 is ensured by the silver brazing layer 7 formed on the fitting part of the end fitting 6. The stability is ensured by the silver solder layer 9 formed on the fitting portion of the mounting bracket 8.

Of the gas passing through the outside of the electric wire 10, the gas that enters the protective tube 11 on the side of the container 13 is blocked at the fitting portion between the end fitting 6 and the mounting fitting 8, as in the case described above. Gas that does not enter the protective cylinder 11 is blocked by the packing 22 of the flange joint 15. Even if a small amount of gas leaks from this part of the gasket 22, it will be dissipated to the outside air, so the airtightness of this part will not be as much of a problem.

Moreover, inside the electric wire insertion tube 14, the container 1
Since there is a large temperature difference between the 3 side and the power supply side,
If there is no insulating compound 12, dew condensation will occur on the outer circumferential surface of the ceramic insulating cylinder 5, and this condensation may cause discharge between the end fitting 6 on the live side and the mounting fitting 8 on the earth potential side. be. However, in this invention, since the insulating mixture 12 is filled around the insulating cylinder 5, no condensation occurs.
In addition, the insulating mixture 12 also has the effect of improving the withstand voltage between phases and between ground.

Note that the wire penetration device of this invention is subject to a heat cycle due to the temperature difference between the temperature of cryogenic liquefied gas such as LNG and room temperature, so the materials of the main body fitting 1, mounting fitting 8, end fitting 6, and insulating cylinder 5 are It is preferable to select one with a thermal expansion coefficient similar to that of the other. In the above embodiment, based on the thermal expansion coefficient of the ceramic insulating cylinder 5, the material of the end fitting 6 and the mounting fitting 8 is Kovar, and the material of the main body fitting 1 is iron/nickel 42.
I chose.

[Experiment example]

The experimental results for the wire penetration device of the above example were as follows.

Insulation resistance...2000MΩ or more Withstand voltage...9000V AC, no abnormality for 10 minutes Water pressure resistance...100Kgf/cm ² G, no abnormality for 10 minutes Heat cycle: 30 minutes in liquefied nitrogen, 30 minutes at room temperature 5
Helium leak test after cycle heat cycle (in liquefied nitrogen) 1×10 ^-9 cc/sec to 1×10 ^-10 cc/sec [Effects of the device] As described above, this device By fitting the end fitting 6 between the conductor pull-out rod 4 and the insulating cylinder 5 and forming the silver brazing layer 7 on the fitting part, high-pressure LNG, etc. in the container 13 can be prevented from leaking to the outside from between the conductor draw-out rod 4 and the insulating cylinder 5. It has the effect of reliably interrupting with high precision. In addition, by fitting the mounting bracket 8 between the insulating cylinder 5 and the main body metal fitting 1 and forming the silver brazing layer 9 on the fitting part, the insulating mixture 12 and the insulating mixture 12 and Between the inner surface of the protective tube 11,
and high pressure LNG from the gap between the insulation mixture 12 itself.
This has the effect of reliably blocking the leakage of foreign substances to the outside with high precision.

In addition, the insulating mixture 12 filled between the insulating tube 5 and the protective tube 11 prevents dew condensation on the outer surface of the insulating tube 5 due to the temperature difference between the container side and the power source side, and prevents condensation on the outer surface of the insulating tube 5. This has the effect of ensuring sufficient withstand voltage between the two.

[Brief explanation of drawings]

Figure 1 is a sectional view of the wire penetration device of the embodiment, Figure 2
The figure is a front view of the main body fitting same as the above, FIG. 3 is a partially enlarged sectional view of the same as the above, and FIG. 4 is a sectional view of the same as the above in an attached state. 1...Body metal fitting, 2...Through hole, 3...Mounting hole, 4...Conductor pull-out rod, 5...Insulating tube, 6...End fitting, 7...Silver raw layer, 8...Mounting metal fitting, 9...
Silver raw layer, 10...Electric wire, 11...Protection tube, 11
a...Large diameter protection tube, 11b...Small diameter protection tube, 12
... Insulating mixture, 13 ... Container, 14 ... Wire insertion tube, 15 ... Flange joint, 16 ... Terminal mounting bracket, 18 ... Cable terminal, 19 ... Bolt, 20 ... Conductor, 21 ... ...Guide pin, 22...
...Patsukin, 23...Pump.

Claims (1)

[Scope of utility model registration request] A through hole 2 is provided in the center of the main body fitting 1 made of a metal plate with a required thickness, and a plurality of mounting holes 3 are provided along the outer periphery of the main body fitting 1.
A ceramic insulating cylinder 5 is attached to the conductor pull-out rod 4 passed through the
, expose both ends of the conductor pull-out rod 4 from both ends of the insulating tube 5, and fit the end fitting 6 in the range from the outer peripheral surface of one end of the insulating tube 5 to the outer circumferential surface of the conductor pull-out rod 4. A silver solder layer 7 is provided in each of the holes, a mounting bracket 8 is fitted in a range extending from the inner peripheral surface of one end of the through hole 2 to the outer peripheral surface of the insulating cylinder 5, and a silver solder layer 9 is provided in the fitted portion, and a conductor drawer is provided. stick 4
Electric wires 10, 10 are connected to both ends of the insulating tubes 11, 11, and insulating protection tubes 11, 11 are inserted in the range extending from the connection portion to the main body metal fitting 1, and an insulating mixture is inserted into the gap between the insulating tube 5 and the protection tubes 11, 11. A wire penetration device for a cryogenic container, which is filled with a substance 12.