JP2006109625A - Method for removing insulating oil from oil-filled cable line - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for quickly removing insulating oil from an oil-filled cable line. <P>SOLUTION: Using a compressor 7, working fluid is supplied to the oil passage in an oil-filled cable line through a connector portion 21a provided or newly provided in the oil-filled cable line. Insulating oil is discharged from a connector portion 21a provided or newly provided in the oil-filled cable line at a point away from the above connector 21a by the working fluid's extrusive force on the insulating oil, and it is recovered. When a suction apparatus 8 is additionally connected to the connector 21a on the insulating oil recovery side to suck the insulating oil, that is more effective. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In the present invention, when an OF cable (Oil-Filled cable) line is replaced or removed, the insulating oil filled in the OF cable line is prevented from leaking and contaminating the surrounding environment. It relates to technology to be extracted in advance.

  The OF cable line is filled with insulating oil for absorbing the expansion and contraction of the cable, and this insulating oil enters and exits between the oil passage in the cable and the hydraulic adjustment tank installed outside. Thus, the expansion and contraction of the cable is absorbed.

  The OF cable line is laid on the bottom of the water (sea floor, river bottom) or underground, if necessary, but the cable may need to be replaced due to deterioration over time, transmission capacity increase, abnormal faults, etc. . Alternatively, in recent years, since the pressure has increased, the CV cable has replaced the OF cable, and it is necessary to remove the existing OF cable line that is no longer used.

  As a countermeasure for preventing the insulating oil from leaking out from the existing OF cable line and contaminating the surrounding environment when replacing or removing the OF cable line, for example, a method described in Patent Document 1 is known. In this method, after the OF cable is cut at a predetermined location, a part of the insulating oil in the oil passage is extracted from the cut end portion, and then the sealing material is injected into the oil passage and the sealing material is solidified. The oil passage is sealed.

Japanese Patent No. 2886255

  The above-mentioned conventional method is, in other words, a method in which the insulating oil is confined in the cut cable by plugging the cut end. Therefore, in the above conventional method, it is considered that the sealing material comes off or breaks and the insulating oil leaks out from it, and the cable is damaged and the insulating oil leaks out from there. It is done. Therefore, it is preferable to extract the insulating oil in the cable line without using the conventional method.

  Then, this invention makes it a subject to provide the method which can extract the insulating oil in OF cable line | wire quickly.

  The present invention is a method for extracting insulating oil in an OF cable line, and supplies a working fluid to an internal oil passage from a connector portion provided on or provided on the OF cable line, and is insulated by the working fluid. Insulating oil is discharged and collected from a connector portion provided on or provided on the OF cable line at a location away from the connector portion by an oil pushing force. That is, according to the present invention, the insulating oil in the OF cable line is caused to flow toward the connector portion on the insulating oil recovery side by the pushing force of the insulating oil by the working fluid, and the insulating oil is discharged therefrom.

  Further, the present invention can employ a configuration in which a suction force is simultaneously applied to the oil passage by the connector portion on the insulating oil recovery side. With this configuration, the fluidity of the insulating oil that flows toward the connector portion on the insulating oil recovery side is enhanced.

  The present invention is also a method for extracting insulating oil in an OF cable line laid on the ground, in the ground, or in the water, wherein the connector on the working fluid supply side is made higher and the connector on the insulating oil recovery side The structure which makes a part a low-order side is employable. According to this configuration, since the insulating oil receives a force that flows to the lower side due to the gravity action of the insulating oil, the fluidity of the insulating oil that flows toward the connector portion on the insulating oil recovery side is further enhanced.

  As described above, according to the present invention, the working fluid is supplied from one connector portion to the internal oil passage, and the insulating oil is ejected from the other connector portion by the pushing force of the insulating oil by the working fluid and recovered. Therefore, the insulating oil in the OF cable line can be quickly extracted.

  In addition, if the other connector portion simultaneously applies a suction force to the oil passage, the fluidity of the insulating oil can be improved, so that the insulating oil can be extracted more rapidly.

  Hereinafter, an insulating oil draining method in an OF cable line according to an embodiment of the present invention will be described. Prior to this, an OF cable line to which the method according to the present embodiment is applied will be briefly described with reference to FIG. .

  The OF cable line includes an OF cable 1, a cable branch part 2, a cable line terminal part 3, and a cable connection part 4. The cable branch portion 2 is a portion for branching, for example, a three-core OF cable 1 into each phase, and is generally called a “branch box”. The cable line end portion 3 is disposed at the end rising portion of the OF cable line, is insulated by the glass tube 31 and the upper cover 32, and is generally called a “termination junction box”. The cable connection portion 4 is a portion that connects the adjacent OF cables 1 and 1 in a straight line, and is generally called a “straight connection box”. These configurations are the same as existing ones.

  In such an OF cable line, an oil tank 6 is connected to the cable branch portion 2 through an oil supply pipe 5. More specifically, the oil supply pipe 5 is connected to a connector portion 21a formed in the housing 21 constituting the cable branching portion 2 and communicating with the internal oil passage, so that it is formed over substantially the entire length of the cable line. The oil passage and the inside of the oil tank 6 are connected via an oil supply pipe 5.

  The description of the OF cable line is as described above. Next, the insulating oil draining method according to the present embodiment will be described with reference to FIG. The cable line in FIG. 2 is a schematic representation of the cable line in FIG.

  First, the connector part 21a of each cable branch part 2 is opened, and in this state, the compressor 7 is connected to the connector part 21a of one cable branch part 2, and the connector part 21a of the other cable branch part 2 is connected. The suction machine 8 is connected to.

  The compressor 7 is for generating compressed air and forcing it into the OF cable line via the connector part 21a of one cable branch part 2, while the suction machine 8 is for the other cable branch. The insulating oil in the OF cable line is sucked through the connector part 21a of the part 2 and is recovered.

  Then, next, the compressor 7 is operated and compressed air is supplied from one cable branch part 2 to an oil passage. Thereby, the insulating oil in the OF cable line is pushed by the compressed air, flows to the other cable branch part 2 side, and is discharged from the open connector part 21 a of the other cable branch part 2. Further, by operating the suction machine 8 at the same time, the insulating oil flowing toward the other cable branch 2 is sucked, thereby promoting the fluidity of the insulating oil.

  As described above, according to the insulating oil draining method according to the present embodiment, compressed air is supplied to the oil passage at a location away from the location where the insulating oil is desired to be drained, and the pushing force is applied to the insulating oil. By applying a suction force to the oil passage at a location where the oil is to be extracted, the insulating oil in the OF cable line can be quickly extracted.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of this invention.

  For example, in the above-described embodiment, the compressor 7 and the suction device 8 are connected to the connector portions 21a and 21a for refueling, and compressed air is supplied from one connector portion 21a to the oil passage and from the other connector portion 21a. Although the insulating oil in the oil passage is sucked, these portions are not limited to the connector portions 21a and 21a for oil supply. For example, a connector portion for oil collection is used to inspect the deterioration degree of the insulating oil. If provided separately, the compressor 7 and the suction machine 8 may be connected thereto.

  Further, in the above embodiment, the compressor 7 and the suction machine 8 are connected to the end of the OF cable line and the insulating oil in the OF cable line is extracted at one time. For example, the OF cable line May be divided into a plurality of sections, and the insulating oil may be extracted for each section. In this case, as shown in FIGS. 1 and 2, since the connector 41a is also formed in the housing 41 constituting the cable connecting portion 4, the compressor 7 and the suction machine 8 may be connected to the connector 41a. .

  Moreover, in the said embodiment, since it is the 3-core OF cable 1, although the cable branch part 2 is provided separately from the cable line termination part 3, if it is a single-core OF cable, a cable line termination part will be provided. Since the connector portion for refueling is provided in this, the compressor 7 and the suction device 8 are connected here. Further, even in the case of the three-core OF cable 1, a connector portion for refueling may be provided at the cable line end portion 3, and this can be used.

  Moreover, in the said embodiment, although the extraction of the insulating oil for 3 core OF cable 1 is demonstrated, if it is a single core OF cable, three will be laid corresponding to 3 phases. Therefore, the insulation oil is extracted for each OF cable.

  Moreover, in the said embodiment, although insulating oil is extracted using the existing connector part 21a, when extracting insulating oil, a connector part is newly formed on an OF cable track, and this is utilized. You may do it.

  Moreover, in the said embodiment, although the compressor 7 and the suction device 8 should be connected clearly to which connector part each should be connected, for example, the OF cable track is along an inclined surface such as a mountain surface. If the compressor 7 is connected to the higher connector portion and the suction device 8 is connected to the lower connector portion, the insulating oil is lowered by the gravity action of the insulating oil. Since the force flowing to the side is received, the insulating oil in the OF cable line can be extracted more quickly.

  Moreover, in the said embodiment, although compressed air is supplied using the compressor 7, in short, what is necessary is just to be able to make pushing force act on the insulation oil in OF cable track, Therefore The compressor is merely an example. The working fluid may be any fluid that does not pollute the surrounding environment, such as gas other than air or water.

  Moreover, in the said embodiment, although the suction machine 8 is used together with the compressor 7, a suction machine is only an illustration like the compressor. Moreover, when the pushing force of the insulating oil by the compressor 7 is sufficient, the suction device 8 is unnecessary.

The conceptual diagram of the conventional OF cable track is shown. The conceptual diagram of the OF cable track | line which applied the insulating oil draining method which concerns on this embodiment is shown.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... OF cable, 2 ... Cable branch part, 21 ... Housing, 21a ... Connector part, 3 ... Cable line terminal part, 31 ... Glass pipe, 32 ... Upper cover, 4 ... Cable connection part, 41 ... Housing, 41a ... Connector 5, oil supply pipe, 6 ... oil tank, 7 ... compressor, 8 ... suction machine

Claims (4)

  A method for extracting insulating oil from an OF cable line, wherein working fluid is supplied to an internal oil passage from a connector portion provided on or provided on the OF cable line, and the pushing force of the insulating oil by the working fluid The insulating oil is extracted from the OF cable line by discharging the insulating oil from the connector part provided on or provided on the OF cable line at a location away from the connector part.   The method for extracting insulating oil in an OF cable line according to claim 1, wherein a suction force is applied to the oil passage at the insulating oil recovery side connector portion simultaneously.   A method for extracting insulating oil from an OF cable line laid on the ground, in the ground, or underwater, with the connector on the working fluid supply side set to the high side and the connector on the insulating oil collection side set to the low side The insulating oil draining method in the OF cable line according to claim 1 or 2.   Each of the connector part on the working fluid supply side and the connector part on the insulating oil recovery side is a connector part provided at a terminal part of the OF cable line or a connector part provided at a cable connection part in the middle of the OF cable line. The method for draining insulating oil in an OF cable line according to any one of claims 1 to 3.

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