CN109768509B - Elbow type joint special for electrified repair of power cable, repair device and method - Google Patents
Elbow type joint special for electrified repair of power cable, repair device and method Download PDFInfo
- Publication number
- CN109768509B CN109768509B CN201910215189.9A CN201910215189A CN109768509B CN 109768509 B CN109768509 B CN 109768509B CN 201910215189 A CN201910215189 A CN 201910215189A CN 109768509 B CN109768509 B CN 109768509B
- Authority
- CN
- China
- Prior art keywords
- cable
- repair
- elbow
- liquid
- joint
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000008439 repair process Effects 0.000 title claims abstract description 170
- 238000000034 method Methods 0.000 title claims abstract description 29
- 239000007788 liquid Substances 0.000 claims abstract description 191
- 238000003860 storage Methods 0.000 claims abstract description 32
- 238000001035 drying Methods 0.000 claims abstract description 16
- 238000002347 injection Methods 0.000 claims description 91
- 239000007924 injection Substances 0.000 claims description 91
- 210000002310 elbow joint Anatomy 0.000 claims description 50
- 238000002788 crimping Methods 0.000 claims description 32
- 230000008569 process Effects 0.000 claims description 9
- 238000012360 testing method Methods 0.000 claims description 8
- 238000010276 construction Methods 0.000 claims description 7
- 238000003780 insertion Methods 0.000 claims description 7
- 230000037431 insertion Effects 0.000 claims description 7
- 238000002360 preparation method Methods 0.000 claims description 7
- 238000009434 installation Methods 0.000 claims description 6
- 238000009413 insulation Methods 0.000 abstract description 18
- 230000002035 prolonged effect Effects 0.000 abstract description 3
- 239000007789 gas Substances 0.000 description 16
- 230000032683 aging Effects 0.000 description 9
- 238000005516 engineering process Methods 0.000 description 7
- 210000003128 head Anatomy 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 238000007605 air drying Methods 0.000 description 5
- 229920003020 cross-linked polyethylene Polymers 0.000 description 5
- 239000004703 cross-linked polyethylene Substances 0.000 description 5
- 240000005572 Syzygium cordatum Species 0.000 description 4
- 235000006650 Syzygium cordatum Nutrition 0.000 description 4
- 208000027418 Wounds and injury Diseases 0.000 description 4
- 230000008033 biological extinction Effects 0.000 description 4
- 230000006378 damage Effects 0.000 description 4
- 238000013461 design Methods 0.000 description 4
- KPUWHANPEXNPJT-UHFFFAOYSA-N disiloxane Chemical class [SiH3]O[SiH3] KPUWHANPEXNPJT-UHFFFAOYSA-N 0.000 description 4
- 208000014674 injury Diseases 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 210000001503 joint Anatomy 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- KWOLFJPFCHCOCG-UHFFFAOYSA-N Acetophenone Chemical compound CC(=O)C1=CC=CC=C1 KWOLFJPFCHCOCG-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 239000003292 glue Substances 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 210000001331 nose Anatomy 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 230000003449 preventive effect Effects 0.000 description 2
- 230000035882 stress Effects 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- 206010035148 Plague Diseases 0.000 description 1
- 241000607479 Yersinia pestis Species 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000006482 condensation reaction Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
The invention discloses a special elbow-shaped connector for live repair of a power cable, a live repair device and a live repair method. The special elbow type connector, the repair liquid storage tank, the gas drying tank, the air compressor and the like form the electrified repair device, so that insulation repair of an aged cable can be realized on the premise of not influencing normal operation of the power cable, the service life of the cable is greatly prolonged, the problem of overlong power failure time is not required, the cable repair device has very high cable repair efficiency, and the cable repair device is suitable for popularization and use in the field.
Description
Technical Field
The invention belongs to the technical field of power cable repair, relates to a power cable live repair technology capable of being used after long-time operation insulation aging, and particularly relates to a special elbow joint for power cable live repair and a power cable live repair method.
Background
Crosslinked polyethylene (XLPE) power cables have excellent electrical, mechanical and heat resistance properties, etc., and thus are widely used in urban grid construction.
Early cable manufacturing process is not high and waterproof nature is not good, and in production, transportation and operation etc. process, can inevitably produce some local defect in the insulating layer, the moisture that gets into in XLPE is insulating through various channels can gather in the microdefect department under the effect of electric field to initiate the water tree, under the effect of overvoltage, the water tree point is easy to be initiated the electricity generation tree, further probably leads to cable insulation body breakdown. With the increase of the service life of the cable, the aging problem of urban cables in China is serious, the aging problem still plagues the power department in spite of the great improvement of the water tree resistance of the cable in recent years, and most of early aged cables are buried underground and concentrated in a central urban area, so that huge engineering quantity and huge cost are generated by directly replacing the aged cables. Therefore, the cable repair technology is adopted to repair the local aging area of the cable, so that the service life of the cable is prolonged, a large amount of manpower and material resources are saved, and the cable repair technology has practical significance.
XLPE cable repair technology has been internationally known for over 30 years. Early attempts have been made to inject dry nitrogen and acetophenone into the cable core, but the repair effect is not ideal and the economic benefit is not high; after that, it has been found that the siloxane has a unique effect in the field of cable repair, and under the action of the catalyst, the siloxane can consume the moisture in the cable insulation layer through the hydrolysis condensation reaction, and generate an oligomer to fill the water tree cavity, thereby achieving the purpose of prolonging the service life of the cable. To date, the Novinium corporation of America developed two-generation repair solutions based on the siloxane repair principle, the first generation being 841 technology, which can effectively prolong the cable life by 10 to 15 years; the second generation is 732/733 technology, which improves the siloxane and catalyst formulation and has better performance by adding additives such as voltage stabilizers, antioxidants, etc. to suppress partial discharge.
In order to reliably inject the repair liquid into the cable core, a special joint adapter is required to connect the cable head with the injection device. US7658629B2 discloses a cable connection fitting for cables connected to other electrical components via copper noses, which is not applicable if the cable is connected to a switchgear, a box-type substation or the like via an elbow joint. US7538274B2 discloses a high voltage connector which requires removal of the cable intermediate connector before use and then fixing of the two cables in the connector, the injection process being completed through the injection conduit which can withstand greater pressures and shorten the construction time, but unlike the previous US patent, the injection process requires a power outage. US7331806B2 discloses a cable connector with an internal reservoir, the interior of the connector being designed as a multi-cavity structure, which prolongs the time for the repair liquid to pass through the cable and reduces the influence of the external environment on the repair liquid process; however, the internal structure of the design is complex, the production cost is high, the price is high, the repairing method is complex, and the technical popularization is difficult.
Domestic cable repair technology is still in the starting stage. The patent application CN200410072791.5 discloses a power cable repair liquid injection system, the repair process of which requires a whole power outage, and there is no specific description how to reliably connect the injection device with the cable head. The patent application document with the application number of CN201010028136.5 discloses a crosslinked polyethylene power cable live repair device and a live repair method thereof, wherein an adapter is only suitable for a cable with a copper nose arranged on a cable head, and if the cable is connected with a switch cabinet, a box-type transformer substation and the like through an elbow joint, the method is not suitable.
Disclosure of Invention
The invention aims at overcoming the defects of the prior art, and provides a special elbow joint for electrified repair of a power cable, so that the connection between a repair liquid injection device and the cable elbow joint is realized, and further the injection of the repair liquid can be completed under the condition of no power failure.
The invention further aims to provide a power cable live repair device and method based on the special elbow type connector.
The invention designs an elbow type connector special for live repair of a power cable, which is similar to the elbow type connector in structure according to an elbow type structure used for connecting the power cable on the existing live operation equipment (such as a switch cabinet, a box type transformer substation and the like), and comprises an elbow type insulating shell, a liquid injection connector assembly and a conductive assembly, wherein the liquid injection connector assembly and the conductive assembly are arranged on one side of the elbow type insulating shell; the elbow type insulating shell is internally of a hollow structure, and an elbow type cavity for accommodating the conductive component is formed; the conductive component comprises a conductive rod and a crimping terminal, wherein the conductive rod is used for being electrically connected with a cable connecting terminal of the live operation equipment, the crimping terminal is used for being electrically connected with a cable to be repaired, the conductive rod is connected with the crimping terminal and is arranged in an elbow-shaped cavity of the shell, and free connecting ends of the conductive rod and the crimping terminal face to two outlet directions of the elbow-shaped cavity respectively; the liquid injection joint assembly comprises a liquid injection joint arranged on one side of the elbow-type insulating shell and a cap matched with the liquid injection joint, and a liquid injection channel extending to the crimping terminal is arranged on the inner side of the liquid injection joint. Through above-mentioned special elbow type of electrified restoration of power cable connects, can replace the original elbow type that uses on electrified operation equipment in restoration power cable repair process and connect, realize the insulation restoration to power cable under the circumstances that does not influence electrified operation equipment normal work.
Above-mentioned special elbow formula of electrified restoration of power cable connects, crimping terminal is tubular conductive part, and its lateral wall design has a plurality of inwards sunken contacts, and this contact forms the electricity with the cable core of waiting to repair of inserting crimping terminal to be connected, has seted up the conducting rod mounting hole on the other end lateral wall opposite with the cable core insertion end on the crimping terminal. Therefore, the conducting rod and the cable core of the cable to be repaired can be kept in good electrical connection, and normal operation of the electrified operation equipment is ensured.
According to the elbow type connector special for live repair of the power cable, the conductive assembly is fixed in the cavity of the elbow type insulating shell through the inner semi-conductive layer, the inner wall structure of the inner semi-conductive layer is matched with the shapes of the conductive rod and the crimping terminal, and the limiting step for clamping the crimping terminal is designed at the end part of the inner semi-conductive layer matched with the outer wall of the crimping terminal; in a preferred implementation, the inner surface of the limiting step is conical in the circumferential direction to facilitate insertion of the cable core. The outer sides of the elbow-shaped insulating shell, the liquid injection joint and the cap are all provided with outer semi-conductive layers. The inner semi-conductive layer and the outer semi-conductive layer are made of conductive rubber. The inner semi-conductive layer can effectively control electric stress, the outer semi-conductive layer is matched with the cable shield to realize shielding continuity, and the outer semi-conductive layer is ensured to be in a grounding state.
Above-mentioned special elbow formula of electrified restoration of power cable connects, when not using, in order to realize annotating the omnidirectional of liquid joint and seal, the inside design of block has from the lid top inner wall extension, be used for inserting annotating the insulating rod of liquid passageway. In a preferred implementation manner, the inner wall of the liquid injection channel of the liquid injection connector and the outer side wall of the cap insulating rod corresponding to the inner wall are designed to be of a wavy undulating structure, so that the liquid injection connector has two functions: (1) The creepage phenomenon is restrained by increasing the surface distance from the inside of the special elbow joint to the outer semi-conductive layer through the liquid injection channel; (2) The insulating rod on the cap can be tightly combined with the liquid injection channel, and is not easy to fall off. In order to further increase the combination firmness of the cap and the liquid injection joint, a limiting protrusion is designed on the inner wall of the cap, and a limiting groove matched with the limiting protrusion is designed on the corresponding position of the outer wall of the liquid injection joint.
The elbow type connector special for live repair of the power cable is provided with the pull ring on the elbow type insulating shell for convenient assembly and disassembly. The elbow-shaped insulating shell is also provided with a grounding eye which is used for being connected with a grounding wire.
The invention further provides a power cable live repair device based on the special elbow joint for live repair of the power cable, which comprises a plurality of special elbow joints for live repair of the power cable, a repair liquid storage tank, a gas drying tank, an air compressor and a residual liquid collection tank; the special elbow connectors for live repair of the power cables are used for connecting the cable connecting terminals of the live operation equipment with the cables to be repaired; the repair liquid storage tank, the gas drying tank and the air compressor are sequentially communicated through pipelines; the output port of the repair liquid storage tank is communicated with an elbow joint liquid injection joint connected with one end of the cable to be repaired through a pipeline, and the input port of the residual liquid collection tank is communicated with an elbow joint liquid injection joint connected with the other end of the cable to be repaired. The number of the elbow-type connectors special for live repair of the power cable is twice that of the power cable to be repaired.
Above-mentioned electrified prosthetic devices of power cable, repair liquid holding vessel and elbow type connect annotate on the pipeline that liquid connects intercommunication and raffinate holding vessel and elbow type connect annotate on the pipeline that liquid connects intercommunication all are provided with the valve for inflow and the flow size of control repair liquid. The valve is a liquid valve.
When the power cable live repairing device and the air compressor work, compressed air is pressed into the air drying tank through the air tank and the compressor, so that moisture in the air is absorbed, and water molecules are prevented from entering the cable along with repairing liquid, and the repairing effect is prevented from being influenced; the dry air is continuously pressed into the repair liquid storage tank to transfer pressure to the repair liquid, and the repair liquid with pressure formed by the dry air is injected into the cable core of the power cable through the liquid injection channel of the special elbow joint.
Above-mentioned electrified prosthetic devices of power cable to be convenient for control repair liquid or gas flow size to and convenient operation and equipment safety, install manometer, handle and liquid level gauge on the repair liquid holding vessel, install handle and relief valve on the raffinate is collected and is irritated, install manometer, handle and relief valve on the gas drying is irritated, install air on the air compressor and irritate and the manometer. The air compressor and the repair liquid storage tank can adjust the pressure of the compressed gas to 0.2-0.8MPa according to the pressure gauge, so that the flow rate of the repair liquid reaches a proper size, and the low-pressure injection is kept. The repair liquid storage tank can observe the residual quantity of the repair liquid through a liquid level meter. The safety valve arranged on the residual liquid collecting tank and the gas drying tank can overflow from the safety valve when the pressure exceeds a limited range, so that the safety is ensured. In addition, be provided with the repair liquid filling opening on the repair liquid holding vessel, when the liquid level gauge shows lowerly, can in time supply repair liquid in to the repair liquid holding vessel through the repair liquid filling opening to avoid influencing the normal clear of power cable repair work. The repair liquid may be any repair liquid for insulation and aging of a cable, and the repair device may be used for injecting other gases or liquids into a power cable.
The invention further provides a power cable live repair method based on the power cable repair device, which is carried out by using the power cable live repair device according to the following steps:
(1) Preparation before repair
Before repairing, power is cut off from the live operation equipment, electric parameters of the cable are measured after power cut off, and the aged cable is selected as the cable to be repaired; carrying out an air circulation test on the cable to be repaired to ensure that the repair liquid can be penetrated; the method specifically comprises the following sub-steps:
(11) The power failure and the safety preparation are carried out, and the power failure flow and other preparation works (such as power inspection, rail arrangement, hanging of a signboard and the like are carried out before equipment is contacted) are strictly carried out according to related systems in the field, so that the safety and the order of repair construction are ensured;
(12) Insulation test after power failure, dismantling the cable from the live operation equipment after power failure, measuring insulation resistance, absorption ratio, dielectric loss or leakage current of the cable (according to DL/T596-2005 electric power equipment preventive test procedure, by related professionals, suggesting to measure more than two items), and recording test data;
(13) Determining a target cable, and selecting a cable meeting the aging requirement as the target cable according to the cable aging condition and the insulation test result to perform insulation repair;
(14) The on-site assembly debugging repair system adopts an air injection system formed by an air compressor and an air drying tank connected with the air compressor, and dry air with set pressure (injection air pressure of 0.2-0.6MPa is selected according to the length of the cable and the thickness of insulation) is introduced into a target cable, so that the air tightness at a joint is ensured, and the repair liquid can be penetrated;
(2) Repair construction process
Removing elbow connectors arranged on live operation equipment, installing special elbow connectors for live repair of a power cable, and respectively connecting special elbow connector liquid injection connectors connected with two ends of a cable to be repaired with a repair liquid storage tank and a residual liquid collection tank through pipelines; restoring the power supply to the electrified operation equipment after the installation is finished, simultaneously starting an air compressor to perform low-pressure injection, injecting the dried air into a repair liquid storage tank, then injecting the repair liquid under pressure into the cable to be repaired through an elbow joint until the repair liquid is injected into the whole cable, and recovering the redundant repair liquid from the residual liquid collection tank through a pipeline; then closing the air compressor, and simultaneously introducing a small amount of gas into the injection end of the cable to enable the redundant repair liquid to flow out from the other end; the method specifically comprises the following sub-steps:
(21) Removing the elbow joint connected with the target cable on the live operation equipment, and replacing the special elbow joint for live repair of the power cable according to the conventional elbow joint installation step, so that the conducting rod in the cavity of the elbow insulating shell is abutted with the cable connecting terminal of the live operation equipment, and the cable core of the cable to be repaired is abutted with the crimping terminal;
(22) The method comprises the steps that a special elbow joint liquid injection joint connected with two ends of a cable to be repaired is connected with a repair liquid storage tank and a residual liquid collection tank through a pipeline respectively, the repair liquid storage tank is used for providing repair liquid, and the residual liquid collection tank is used for collecting the repair liquid flowing out from the other end of the cable; in order to ensure that the repairing liquid does not leak under larger air pressure, the pipeline and the special elbow joint upper liquid injection joint can be connected together through accessories such as insulating filling glue or a clamp;
(23) Restoring the power supply to the electrified operation equipment according to the regulation after the installation is completed;
(24) Under the condition of ensuring air tightness, the air compressor is regulated to gradually increase the air pressure, compressed air output by the air compressor is dried by the air drying tank and then is continuously pressed into the repair liquid storage tank, so that repair liquid in the repair liquid storage tank is injected into a cable core to be repaired through a special elbow joint; the whole injection process is electrified, and the injection time is determined by the length, the section, the flow resistance and the like of the cable; the gas drying tank is used for drying air, removing moisture in the air and preventing the moisture in the air from entering the cable to be repaired to influence the repair effect; valves may be used to control the flow of repair fluid and to address certain special situations (e.g., rapid closing of the valve upon repair fluid leakage interrupts the supply);
(25) Closing an air compressor after repairing liquid is injected into the whole cable to be repaired, removing a repairing liquid storage tank from a special elbow joint, connecting a gas drying tank with the special elbow joint through a pipeline, introducing dry air into an injection end of the repairing cable, enabling part of superfluous repairing liquid to flow out from the other end, and collecting the superfluous repairing liquid by a residual liquid collecting tank; until no repair liquid overflows from the pore of the cable head (a transparent hose can be used for a pipeline connected with the residual liquid collecting tank for convenient observation, and the overflow condition of the repair liquid is observed from the transparent hose) so as to prevent the repair liquid from flowing out of the cable head due to heat after the cable normally operates;
(3) Repairing subsequent work
After the cable is repaired, power is cut off for the live operation equipment, then an elbow-shaped connector arranged on the live operation equipment is removed, the elbow-shaped connector is separated from the repaired cable, and a cap is arranged on a liquid injection connector of the elbow-shaped connector, so that potential electrical hazards such as creepage and the like are prevented, and personal injury is avoided; then restoring the site; the special elbow joint can be used as a conventional elbow joint, so that after the cable is repaired, the cap is mounted on the liquid injection joint of the elbow joint, thereby preventing potential electrical hazards such as creepage and personal injury; and then resumes the field.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the elbow type connector special for live repair of the power cable, the power cable is normally used through the conductive component arranged in the elbow type insulating shell, and meanwhile, the repair liquid is injected into the aged cable through the liquid injection connector arranged on the elbow type insulating shell, so that insulation repair of the aged cable can be realized on the premise that normal operation of the power cable is not affected, and the technical blank of live repair of the cable with the elbow type connector is filled.
2. The special elbow type connector for the electrified repair of the power cable is convenient to install and simple to operate, can be used as a conventional elbow type connector without dismantling, has high cable repair efficiency when being used for repairing the cable, and is suitable for popularization and use in the field.
3. When the elbow type connector special for live repair of the power cable is not used, the cap is arranged on the liquid injection connector, so that potential electrical hazards such as creepage can be prevented, personal injury is avoided, and safe operation of the power cable is ensured.
4. The live repair method of the power cable provided by the invention only has the possibility of short power failure time when the elbow type connector is replaced (the problem is not existed if the live operation equipment is a special elbow type connector), and the aged cable can be repaired in a live mode after the elbow type connector is installed, so that the power failure time is greatly shortened, and the service life of the cable is prolonged.
5. According to the live repair method for the power cable, provided by the invention, even if an intermediate joint exists and the repair liquid is injected into an aged cable at low pressure, the live repair can be realized, and the problem of overlong power failure time is not required to be worried about.
6. According to the power cable live repair method provided by the invention, as a low-pressure injection method can be adopted, complex equipment such as a vacuum liquid suction device is not needed, so that the repair device is simpler and the economic cost is lower.
Drawings
Fig. 1 is a schematic diagram of an elbow-type joint structure special for live repair of a power cable.
Fig. 2 is a schematic diagram of the live repair device for the power cable of the invention.
In the figure, a special elbow connector for 1, a special elbow type insulating shell, a 1-1 conducting rod, a 1-3 crimping terminal, a 1-4 liquid injection connector, a 1-4-1 liquid injection channel, a 1-4-2 limiting groove, a 1-5 cap, a 1-5-1 insulating rod, a 1-5-2 limiting bulge, a 1-6 inner semiconductive layer, a 1-6-1 limiting step, a 1-7 outer semiconductive layer, a 1-8 pull ring, a 1-9 grounding eye, a 2 repair liquid storage tank, 2-1, 3-1, 4-2 pressure gauges, 2-2, 3-2, 5-1 handles, 2-3 liquid level gauges, 3 gas drying tanks, 3-3, 5-2 safety valves, 4 air compressors, 4-1 air tanks, 5 residual liquid collection, 6 cables, 7 switch cabinets, 7-1 bushings, 7-2 arc extinction insertion rods and 8 valves.
Detailed Description
The present invention will now be described in more detail by way of examples, which are given herein for further illustration only and are not to be construed as limiting the scope of the invention, as many insubstantial modifications and adaptations of the invention will now occur to those skilled in the art in light of the foregoing disclosure.
Example 1 Special elbow-type connector for live repair of Power Cable
The embodiment provides an elbow joint 1 special for live repair of a power cable, which is suitable for a switch cabinet 7. The cable connecting terminal of the switch cabinet is provided with a sleeve 7-1, and a matched arc extinction inserting rod 7-2 is arranged in the sleeve.
The special elbow type connector structure for live repair of the power cable is shown in fig. 1, and comprises an elbow type insulating shell 1-1, a liquid injection connector assembly arranged on one side of the elbow type insulating shell, and a conductive assembly. The elbow type insulating shell is internally of a hollow structure, and an elbow type cavity for accommodating the conductive component is formed. The conductive component comprises a conductive rod 1-2 and a crimping terminal 1-3, wherein the crimping terminal 1-3 is a copper pipe, a plurality of inwards pressed grooves are formed in the side wall of the crimping terminal, one end of the crimping terminal is a cable core insertion end of a cable to be repaired, and a conductive rod mounting hole is formed in the side wall of the other end of the crimping terminal. The conducting rod 1-2 is arranged in the crimping terminal mounting hole, the conducting rod 1-2 and the crimping terminal 1-3 are fixed in the elbow-shaped insulating shell cavity through the inner semi-conducting layer 1-6, the inner wall structure of the inner semi-conducting layer is matched with the shapes of the conducting rod and the crimping terminal, and the limiting step 1-6-1 for clamping the crimping terminal is designed at the end part of the inner semi-conducting layer matched with the outer wall of the crimping terminal; the inner surface of the limiting step is conical along the circumferential direction so as to facilitate the insertion of the cable core. The free connection ends of the conducting rod and the crimping terminal face to the two outlet directions of the elbow-shaped cavity respectively. A space for accommodating a sleeve is formed between the conducting rod 1-2 and the inner wall of the elbow type insulating shell, and when the special elbow type connector is in butt joint with the cable connecting terminal of the switch cabinet, the conducting rod 1-2 is electrically connected with the arc extinction inserting rod 7-2, so that the conducting rod is electrically connected with the cable connecting terminal of the switch cabinet. The crimp terminal 1-3 has a length shorter than the length of the cavity of the elbow-type insulating housing in which it is located, thereby forming a guide space for guiding insertion of the cable, and after the cable is inserted into the elbow-type insulating housing, the cable core thereof is inserted into the crimp terminal and brought into close contact with the contact piece on the inner wall of the crimp terminal. The liquid injection joint assembly comprises a liquid injection joint 1-4 arranged at one side of the elbow-shaped insulating shell and a cap 1-5 matched with the liquid injection joint, wherein a liquid injection channel 1-4-1 extending to the compression joint terminal is arranged at the inner side of the liquid injection joint 1-4. The inside of the cap is designed with an insulating rod 1-5-1 extending from the inner wall of the top of the cap and used for being inserted into the liquid injection channel, and the inner wall of the liquid injection channel of the liquid injection joint and the outer side of the insulating rod of the cap corresponding to the inner wall of the liquid injection channel are designed into wavy structures. The corresponding positions of the inner wall of the cap and the outer wall of the liquid injection joint are respectively provided with a limit protrusion 1-5-2 and a limit groove 1-4-2 matched with the limit protrusion.
The outer sides of the elbow type insulating shell, the liquid injection joint and the cap are all provided with outer semiconductive layers 1-7. The inner semi-conductive layer and the outer semi-conductive layer are made of conductive rubber. The inner semi-conductive layer can effectively control electric stress, the outer semi-conductive layer is matched with the cable shield to realize shielding continuity, and the outer semi-conductive layer is ensured to be in a grounding state.
The pull rings 1-8 are arranged at the corner positions of the elbow type insulating shell, so that the special elbow type connector is convenient to assemble and disassemble. The semiconducting layer outside the elbow-shaped insulating shell is provided with grounding eyes 1-9 for connection with a grounding wire.
Example 2 Power Cable live repair apparatus
The present embodiment provides a power cable live repair device suitable for a switch cabinet 7 based on the elbow joint special for power cable live repair provided in embodiment 1. For a three-phase cable, which consists of three cables, the two ends of the cable are connected to a switch cabinet, respectively, as shown in fig. 2.
The structure of the power cable live repairing device is shown in fig. 2, and the power cable live repairing device comprises an elbow joint 1 special for power cable live repairing in six embodiments, a repairing liquid storage tank 2, a gas drying tank 3, an air compressor 4 and a residual liquid collecting tank 5. The special elbow joint for live repair of the power cable replaces the original elbow joint of the three-phase cable and is used for connecting the cable connecting terminal of the switch cabinet with the cable to be repaired. The cable is firstly connected into the elbow-shaped insulating shell of the special elbow-shaped connector, and the cable core is inserted into the crimping terminal and is tightly contacted with the contact piece on the inner wall of the crimping terminal, so that the conducting rod and the cable core form good electric contact. And then the special elbow-shaped connector connected with the cable is mounted on the switch cabinet, so that the sleeve of the cable connecting terminal of the switch cabinet is inserted into one side of the elbow-shaped insulating shell, and the conducting rod 1-2 is abutted with the arc extinction inserting rod 7-2, thereby realizing the electric connection between the conducting rod and the cable connecting terminal of the switch cabinet. The repair liquid storage tank 2, the gas drying tank 3 and the air compressor 4 are communicated through pipelines in sequence; the output port of the repair liquid storage tank is communicated with an elbow joint liquid injection joint connected with one end of the cable to be repaired through a pipeline, and the input port of the residual liquid collection tank is communicated with an elbow joint liquid injection joint connected with the other end of the cable to be repaired.
The repairing liquid storage tank 2 is provided with a pressure gauge 2-1, a handle 2-2 and a liquid level gauge 2-3, the gas drying tank 3 is provided with a pressure gauge 3-1, a handle 3-2 and a safety valve 3-3, and the air compressor 4 is provided with an air tank 4-1, a pressure gauge 4-2 and a compressor. The residual liquid collecting tank 5 is provided with a handle 5-1 and a safety valve 5-2. In addition, the repair liquid storage tank is also provided with a repair liquid injection port. The valve 8 is arranged on the pipeline of the repairing liquid storage tank 2 communicated with the elbow joint liquid injection joint and the pipeline of the residual liquid collection tank 5 communicated with the elbow joint liquid injection joint and is used for controlling the inflow and flow of the repairing liquid. The valve is a liquid valve.
Application example
The application example uses the power cable repair device provided in the embodiment 2 to repair the cable for the switch cabinet in an electrified manner, and the steps are as follows:
(1) Preparation before repair
The method comprises the following sub-steps:
(11) The power failure and the safety preparation are carried out, and the power failure flow and other preparation works (such as power inspection, rail arrangement, hanging of a signboard and the like are carried out before equipment is contacted) are strictly carried out according to related systems in the field, so that the safety and the order of repair construction are ensured;
(12) Insulation test after power failure, dismantling the three-phase cable from the electrified operation equipment, measuring insulation resistance, absorption ratio, dielectric loss or leakage current of each phase cable of the three-phase cable (according to DL/T596-2005 electric power equipment preventive test procedure, completed by related professionals, suggesting measurement of more than two items), and recording test data;
(13) Determining a target cable, and selecting a cable meeting ageing requirements (for example, dielectric loss factors are larger than relevant standards) as the target cable according to cable ageing conditions and insulation test results to perform insulation repair;
(14) The on-site assembly debugging repair system adopts an air injection system formed by an air compressor and an air drying tank connected with the air compressor, and dry air with set pressure (injection air pressure of 0.2-0.6MPa is selected according to the length of the cable and the thickness of insulation) is introduced into a target cable, so that the air tightness at a joint is ensured, and the repair liquid can be penetrated;
(2) Repair construction process
The method comprises the following sub-steps:
(21) Removing an elbow joint connected with a target cable 6 on a switch cabinet 7, and replacing the special elbow joint for live repair of the power cable according to a conventional elbow joint installation step to ensure that a conducting rod in a cavity of an elbow type insulating shell is abutted with a cable connecting terminal of live operation equipment, and a cable core to be repaired is abutted with a crimping terminal;
(22) The special elbow joint liquid injection joints connected with the two ends of the cable to be repaired are respectively connected with the repair liquid storage tank and the residual liquid collection tank through pipelines, and the pipelines are reliably connected with the liquid injection joints of the special elbow joints by using accessories such as filling glue, hoops and the like so as to ensure that the repair liquid is not leaked under larger air pressure;
(23) Restoring the power supply to the switch cabinet according to the regulation after the installation is completed;
(24) Under the condition of ensuring air tightness, the air compressor 4 is regulated to gradually increase the air pressure, compressed air output by the air compressor is dried by the air drying tank 2 and then is continuously pressed into the repair liquid storage tank 1, a valve is regulated to enable repair liquid in the repair liquid storage tank to be injected into a cable core to be repaired through the special elbow joint 1, the pressure of the compressed air is regulated to be 0.2-0.8MPa according to the reality of the air compressor and the pressure gauge of the repair liquid storage tank, the flow rate of the repair liquid is enabled to reach a proper size, and the low-pressure injection of the repair liquid is kept; the whole injection process is electrified, and the injection time is determined by the length, the section, the flow resistance and the like of the cable;
(25) Closing an air compressor after repairing liquid is injected into the whole cable to be repaired, removing a repairing liquid storage tank from a special elbow joint, connecting a gas drying tank with the special elbow joint through a pipeline, introducing drying gas into an injection end of the repairing cable, enabling part of superfluous repairing liquid to flow out from the other end, and collecting the superfluous repairing liquid by a residual liquid collecting tank; until no repair liquid overflows from the pore of the cable head (the repair liquid overflows through observing in a transparent hose connected with a residual liquid collecting tank), so as to prevent the repair liquid from flowing out of the cable head due to heating after the cable is normally operated;
repeating the steps (21) - (25), and sequentially performing insulation repair on all the target cables.
(3) Repairing subsequent work
The special elbow joint can be used as a conventional elbow joint, so that after the cable is repaired, the cap 1-5 is mounted on the liquid injection joint 1-4 of the elbow joint, thereby preventing electrical hidden hazards such as creepage and personal injury; and then resumes the field.
Claims (5)
1. The elbow type connector (1) special for the live repair of the power cable is characterized by comprising an elbow type insulating shell (1-1), a liquid injection connector assembly and a conductive assembly, wherein the liquid injection connector assembly and the conductive assembly are arranged on one side of the elbow type insulating shell; the elbow type insulating shell is internally of a hollow structure, and an elbow type cavity for accommodating the conductive component is formed; the conductive component is fixed in the elbow type insulating shell cavity through the inner semi-conductive layers (1-6); the conductive component comprises a conductive rod (1-2) and a crimping terminal (1-3), wherein the conductive rod is used for being electrically connected with a cable connecting terminal of the live operation equipment, the crimping terminal is used for being electrically connected with a cable to be repaired, the conductive rod is connected with the crimping terminal and is arranged in an elbow-shaped cavity of the shell, and free connecting ends of the conductive rod and the crimping terminal face to two outlet directions of the elbow-shaped cavity respectively; the liquid injection joint assembly comprises a liquid injection joint (1-4) arranged at one side of the elbow-shaped insulating shell and a cap (1-5) matched with the liquid injection joint, wherein a liquid injection channel (1-4-1) extending to the crimping terminal is arranged at the inner side of the liquid injection joint (1-4); an insulating rod (1-5-1) extending from the inner wall of the top of the cap and used for being inserted into the liquid injection channel is arranged in the cap; the inner wall of a liquid injection channel of the liquid injection connector and the outer side wall of the cap insulating rod corresponding to the inner wall are designed to be of a wavy structure; a limiting protrusion (1-5-2) is designed on the inner wall of the cap, and a limiting groove (1-4-2) matched with the limiting protrusion is designed on the corresponding position of the outer wall of the liquid injection joint; the outer sides of the elbow-shaped insulating shell, the liquid injection joint and the cap are all provided with outer semi-conductive layers (1-7).
2. The elbow joint special for live repair of power cable according to claim 1, wherein the crimp terminal is a tubular conductive member, a plurality of inwardly recessed contact members are arranged on the side wall of the crimp terminal, the contact members are electrically connected with a cable core of the cable to be repaired inserted into the crimp terminal, and a conductive rod mounting hole is formed in the side wall of the other end of the crimp terminal opposite to the insertion end of the cable core.
3. An electrified repairing device for a power cable, which is characterized by comprising a plurality of elbow connectors (1) special for electrified repairing of the power cable, a repairing liquid storage tank (2), a gas drying tank (3), an air compressor (4) and a residual liquid collecting tank (5); the special elbow connectors for live repair of the power cables are used for connecting the cable connecting terminals of the live operation equipment with the cables to be repaired; the repair liquid storage tank (2), the gas drying tank (3) and the air compressor (4) are communicated through pipelines in sequence; the output port of the repair liquid storage tank is communicated with an elbow joint liquid injection joint connected with one end of the cable to be repaired through a pipeline, and the input port of the residual liquid collection tank is communicated with an elbow joint liquid injection joint connected with the other end of the cable to be repaired.
4. The power cable live repair device according to claim 3, wherein valves are provided on the pipe in which the repair liquid storage tank is communicated with the elbow joint liquid injection joint and on the pipe in which the residual liquid collection tank is communicated with the elbow joint liquid injection joint.
5. A method for live repair of a power cable, characterized in that the method for live repair of a power cable according to claim 3 or 4 is carried out by the following steps:
(1) Preparation before repair
Before repair, power is cut off to the live operation equipment, electric parameters of the cable are measured after power cut off, and the aged cable is selected as the cable (6) to be repaired; carrying out an air circulation test on the cable (6) to be repaired, so as to ensure that the repair liquid can be penetrated;
(2) Repair construction process
Removing elbow connectors configured on live operation equipment, installing a special elbow connector (1) for live repair of a power cable, and respectively connecting a special elbow connector liquid injection connector connected with two ends of a cable to be repaired with a repair liquid storage tank and a residual liquid collection tank through pipelines; restoring the power supply to the electrified operation equipment after the installation is finished, simultaneously starting an air compressor to perform low-pressure injection, injecting the dried air into a repair liquid storage tank, then injecting the repair liquid under pressure into the cable to be repaired through an elbow joint until the repair liquid is injected into the whole cable, and recovering the redundant repair liquid from the residual liquid collection tank through a pipeline; then closing the air compressor, and simultaneously introducing gas into the injection end of the cable to enable the redundant repair liquid to flow out from the other end and be collected by the residual liquid collecting tank;
(3) Repairing subsequent work
After the cable is repaired, power is cut off for the live operation equipment, then an elbow-shaped connector mounted on the live operation equipment is removed, the elbow-shaped connector is separated from the repaired cable, a cap is mounted on a liquid injection connector of the elbow-shaped connector (1), and then the live operation equipment is restored;
or after the cable repair is finished, the cap is mounted on the liquid injection joint of the elbow joint (1), and then the site is restored.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910215189.9A CN109768509B (en) | 2019-03-21 | 2019-03-21 | Elbow type joint special for electrified repair of power cable, repair device and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910215189.9A CN109768509B (en) | 2019-03-21 | 2019-03-21 | Elbow type joint special for electrified repair of power cable, repair device and method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109768509A CN109768509A (en) | 2019-05-17 |
| CN109768509B true CN109768509B (en) | 2024-03-22 |
Family
ID=66459335
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910215189.9A Active CN109768509B (en) | 2019-03-21 | 2019-03-21 | Elbow type joint special for electrified repair of power cable, repair device and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109768509B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112018654B (en) * | 2020-09-01 | 2022-05-17 | 广东电网有限责任公司江门供电局 | Elbow type cable head pulling-out device |
| CN112202012B (en) * | 2020-09-22 | 2022-02-18 | 华南理工大学 | Connector and repair device for bad electrical contact inside high-voltage cable |
| CN112234494B (en) * | 2020-10-10 | 2021-09-21 | 广东海洋大学 | Ship cable gas-liquid composite stage type water tree restoration method |
| CN113471889B (en) * | 2021-05-28 | 2022-10-14 | 国网河北省电力有限公司临漳县供电分公司 | Cable repairing device and cable repairing method |
| CN113555838A (en) * | 2021-07-14 | 2021-10-26 | 国网北京市电力公司 | Overvoltage preventing device for elbow-shaped head of cable terminal |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW432750B (en) * | 1997-06-30 | 2001-05-01 | Cooper Ind Inc | High voltage electrical connector, insert for insertion in an access cavity of the same, dielectric injection plug, and high voltage electrical connector assembly |
| CN103001155A (en) * | 2013-01-04 | 2013-03-27 | 西南交通大学 | Method for intelligently repairing insulating water tree of crosslinked polyethylene power cable |
| CN202977772U (en) * | 2012-12-17 | 2013-06-05 | 广州高力电缆附件有限公司 | Separable connector |
| CN208508494U (en) * | 2018-08-10 | 2019-02-15 | 中航建设集团成套装备股份有限公司 | A kind of cable T-type connect-disconnect plug |
-
2019
- 2019-03-21 CN CN201910215189.9A patent/CN109768509B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW432750B (en) * | 1997-06-30 | 2001-05-01 | Cooper Ind Inc | High voltage electrical connector, insert for insertion in an access cavity of the same, dielectric injection plug, and high voltage electrical connector assembly |
| US6332785B1 (en) * | 1997-06-30 | 2001-12-25 | Cooper Industries, Inc. | High voltage electrical connector with access cavity and inserts for use therewith |
| CN202977772U (en) * | 2012-12-17 | 2013-06-05 | 广州高力电缆附件有限公司 | Separable connector |
| CN103001155A (en) * | 2013-01-04 | 2013-03-27 | 西南交通大学 | Method for intelligently repairing insulating water tree of crosslinked polyethylene power cable |
| CN208508494U (en) * | 2018-08-10 | 2019-02-15 | 中航建设集团成套装备股份有限公司 | A kind of cable T-type connect-disconnect plug |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109768509A (en) | 2019-05-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109768509B (en) | Elbow type joint special for electrified repair of power cable, repair device and method | |
| CN110112611B (en) | Pressure balance type high-voltage cabin penetrating connector and connecting method | |
| CN105606850A (en) | High-voltage DC support insulator test apparatus, test system and system method | |
| CN203481774U (en) | Cable joint | |
| CN103809085A (en) | Junction device for cable high-voltage resistance test and cable high-voltage resistance test | |
| CN112202012B (en) | Connector and repair device for bad electrical contact inside high-voltage cable | |
| CN204142901U (en) | A kind of high voltage power cable test device | |
| CN115792310B (en) | On-site experiment device and method for switching all-in-one machine | |
| CN106054044A (en) | Insulation test device for gas filled tank | |
| CN206976587U (en) | A kind of high-voltage undersea cable rigidity transition joint | |
| JP3349275B2 (en) | Elephant for cable head | |
| CN214124274U (en) | High-voltage test patch cord capable of preventing high-voltage leakage | |
| CN209434791U (en) | Dedicated elbow-type connector and prosthetic device are repaired in power cable electrification | |
| CN104931865B (en) | A kind of Voltage Cable Lines Construction pressure test insulating boot and test method | |
| CN203690874U (en) | Watertight conjunction box | |
| CN215813157U (en) | Capacitive oil paper insulating sleeve aging test platform | |
| CN202749204U (en) | Shrapnel type extractor device of high-voltage bushing end screen | |
| CN103050905B (en) | Switch cubicle ac voltage withstanding insulation annex | |
| CN206236523U (en) | A kind of box switching station and oil-filled transformer 35kV gas-filling cabinet sleeve pipes | |
| Pelissou et al. | Underground medium-voltage cable rejuvenation—Part II: Pilot projects in the field | |
| CN106019022B (en) | Cover plate test device for connecting gas chamber between oil-gas type transformer and GIS and operation method | |
| CN218995455U (en) | Portable insulating cylinder for withstand voltage test | |
| CN220084993U (en) | Insulating main shaft test device | |
| CN205543941U (en) | Connector of transformer high -tension bushing and GIS equipment room | |
| CN113241719B (en) | Waterproof and explosion-proof high-voltage cable intermediate joint and use method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |