Cable fault detection device

Abstract

The invention relates to the technical field of submarine cables, and discloses a cable fault detection device, which comprises a mounting base and a buoy, and is characterized in that a cable body is internally provided with a detection pipe, and the detection pipe is internally provided with a mobile reference module; the movable reference module comprises two end caps, a center rod is fixedly installed between the two end caps, the surface of the center rod is sleeved with an expansion air bag, and when airflow flows in the detection pipe, the movable reference module moves along an inner cavity of the detection pipe. According to the detection device provided by the invention, the detection pipe is arranged in the cable body, the mobile reference module is arranged in the detection pipe, gas is injected into the detection pipe, the mobile reference module is driven to move along the detection pipe, and the underwater sonar detector is used for detecting the moving path of the mobile reference module; according to the dynamic detection mode, the identifiability is high, the detection and analysis difficulty is reduced, the working efficiency is improved, and a guarantee is provided for regular inspection and maintenance of submarine cables.

Description

Technical Field

[0001] The present invention relates to the technical field of submarine cables, and in particular to a cable fault detection device. Background Art

[0002] Submarine cable failures are mainly caused by two reasons: one is electrical failures such as breakdown caused by the submarine cable itself; the other is physical damage caused by external forces such as illegal anchoring by upstream ships and fishing operations. In order to reduce the occurrence of failures, it is necessary to conduct regular inspections of the operating status of submarine cables to detect potential risks in advance. Traditional manual diving inspections are subject to many constraints, low operating efficiency, high safety risks, and are only applicable to shallow sea areas. They cannot meet the power supply guarantee needs under complex sea conditions. Intelligent and efficient submarine cable operation and maintenance methods and guarantee equipment are urgently needed.

[0003] In the prior art, a patent document with announcement number CN116238653A discloses a submarine cable fault monitoring device, including a hull, a fault detector body is installed on the top of the hull, a number of fixed seats are installed on both sides of the hull, a connecting arm is rotatably installed on the fixed seat through a rotating shaft, wherein one end of the connecting arm is connected to the rotating shaft, and the other end of the connecting arm is installed with an auxiliary float through a telescopic mechanism, and a distance adjustment mechanism is installed on the connecting arm, and two tension springs are installed on the distance adjustment mechanism, wherein one end of the tension spring is connected to the distance adjustment mechanism, and the other end of the tension spring is fixed to the side of the hull through a fixed bracket.

[0004] In actual use, the fault detector body is set on the hull. Since it is too far away from the submarine cable, it is suitable for detecting some targets with larger fault defects. For faults caused by damage and leakage of submarine cables that are not obvious in the early stage, this long-distance detection has a small fault target, which is difficult to detect and analyze, and is easy to miss, resulting in a huge workload and low efficiency. Based on this, the existing underwater cable fault detection has the problems of long distance, poor resolution, difficult operation and low work efficiency, which need to be solved urgently. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings of the existing underwater cable fault detection in the prior art, such as long distance, poor resolution, great difficulty in operation and low working efficiency, and to propose a cable fault detection device.

[0006] In order to achieve the above-mentioned objectives, the present invention adopts the following technical solutions: a cable fault detection device, comprising a mounting base and a buoy, a traction rope is connected between the mounting base and the buoy, a pressure relief valve is arranged in the buoy, a flow guide assembly is arranged in the mounting base, the pressure relief valve is connected to the flow guide assembly through a connecting pipe, and a cable body laid underwater is fixedly connected to the mounting base.

[0007] A detection tube is arranged inside the cable body. The diversion assembly is communicated with the inner cavity of the detection tube. A mobile reference module is arranged inside the detection tube. The mobile reference module includes two end caps. A central rod is fixedly installed between the two end caps. An expansion airbag is sleeved on the surface of the central rod. When the air pressure inside the detection tube changes, the volume of the expansion airbag becomes larger or smaller, so that the outer surface of the expansion airbag makes sliding contact with the inner wall of the detection tube. When there is air flow inside the detection tube, the mobile reference module is driven to move along the inner cavity of the detection tube. The mobile reference module moves along the detection tube, and an underwater sonar detector is used to detect the movement path of the mobile reference module, so as to detect the defective positions of damage, deformation or fracture of the cable body.

[0008] Preferably, the diversion assembly includes a drainage cover. A first joint and a second joint are respectively fixedly installed at both ends of the drainage cover. The end of the connecting pipe far away from the buoy is communicated with the inner cavity of the drainage cover. Both the first joint and the second joint are communicated with the detection tube. A valve sleeve and a support sleeve are fixedly installed inside the drainage cover. A transmission rod is slidably installed inside the support sleeve. A valve plug is fixedly installed at the end of the transmission rod. A return spring is arranged between the support sleeve and the valve plug. Under the action of the return spring, the valve plug slides into the valve sleeve. The valve sleeve is communicated with the orifice of the first joint. The opening and closing of the first joint are controlled by the movement of the valve plug.

[0009] Among them, a plurality of plugging blocks are arranged inside the detection tube. The plurality of plugging blocks divide the inner cavity of the detection tube into multiple segments. The first joint and the second joint are respectively communicated with the inner cavities of the detection tube on both sides of the plugging block, so that the air flow inside the detection tube flows in one direction, thereby achieving the effect of driving the mobile reference module to move in a fixed direction.

[0010] Preferably, a permanent magnet block is embedded inside the transmission rod, and a first spiral coil is embedded inside the support sleeve. After the first spiral coil is energized, a repulsive or attractive force magnetic to the permanent magnet block is generated. After the first spiral coil is energized, it adsorbs the transmission rod to act, so that the valve plug is opened, and the air flow enters the detection tube from the first joint, driving the mobile reference module to return along the original path inside the detection tube, meeting the requirement that the mobile reference module can be reused.

[0011] Preferably, an induction wire is embedded inside the end cap. An installation ring is fixedly installed inside the end cap. A second spiral coil is embedded inside the installation ring. The induction wire is electrically connected to the second spiral coil. A permanent magnet ring is slidably sleeved on the surface of the central rod, and the permanent magnet ring contacts the end face of the expansion airbag.

[0012] Preferably, when the cable body is energized, a magnetic field is generated in the cable core of the cable body. An air flow is injected into the detection tube to push the mobile reference module to move along the inner cavity of the detection tube. After the magnetic induction current generated by the induction wire cutting the magnetic field is introduced into the second spiral coil, the second spiral coil generates a repulsive or attractive force with the magnetic ring of the permanent magnet. By changing the pressure of the permanent magnet ring on the expansion airbag, the size of the expansion airbag is adjusted, thereby changing the moving speed of the mobile reference module.

[0013] When the mobile reference module moves along the inner cavity of the detection tube, an underwater sonar detector is used to detect the moving path of the mobile reference module. This dynamic detection method has strong recognition, reduces the difficulty of detection and analysis, and improves work efficiency.

[0014] Preferably, when the cable body is powered off, the magnetic field around the cable core of the cable body disappears, and the volume of the expansion airbag shrinks, so that an air ventilation gap is generated between the outer surface of the expansion airbag and the inner wall of the detection tube. The inner cavity of the detection tube is communicated through the ventilation gap. Under normal conditions, the entire inner cavity of the detection tube is in a communicating state. Air is injected into the detection tube to detect the air pressure change in the detection tube, so as to monitor the safety of the entire cable body.

[0015] The present invention has the following beneficial effects: 1. The detection device proposed by the present invention, by arranging a detection tube in the cable body and a mobile reference module in the detection tube, injecting gas into the detection tube to drive the mobile reference module to move along the detection tube, and using an underwater sonar detector to detect the moving path of the mobile reference module, so as to detect the defective positions of breakage, deformation or fracture of the cable body. This dynamic detection method has strong recognition, reduces the difficulty of detection and analysis, and improves work efficiency, providing guarantee for the regular inspection and maintenance of submarine cables.

[0016] 2. The detection device proposed by the present invention, when the air flow rate injected into the detection tube is constant, by changing the pressure of the permanent magnet ring on the expansion airbag, adjusting the size of the expansion airbag, thereby changing the moving speed of the mobile reference module, to meet the use requirements of different detections; For example, when the cable body is deformed and there is a narrow area in the inner cavity of the detection tube, the narrow area blocks the movement of the mobile reference module from passing through, achieving the effect of detecting the position of the narrow area. Then, the volume of the expansion airbag is reduced to facilitate the mobile reference module to pass through the narrow area for subsequent detection tasks. Or, when the cable body has different degrees of leakage and the input flow rate is close to the leakage flow rate, the mobile reference module will stay near the leakage point to better determine the leakage position and facilitate maintenance.

[0017] 3. The detection device proposed by the present invention sets two buoys in a cable section of a certain length. When the maintenance ship sails to the positions of the two buoys, air is injected into the detection pipe at the position of the pressure relief valve, driving the mobile reference module to move along the detection pipe. The mobile reference module will stop at the cable body fracture point, thereby detecting the specific cable fracture position, such as the burial depth parameter and the offset position of the broken head, facilitating salvage and repair.

[0018] 4. The detection device proposed by the present invention controls the opening and closing of the first joint through the movement of the valve plug in the drainage cover. When injecting air into the detection pipe at the buoy, the first joint is closed by using the valve plug, so that the air flow in the detection pipe flows in one direction, thereby achieving the effect of driving the mobile reference module to move in a fixed direction; Since a first spiral coil is arranged in the support sleeve, after the first spiral coil is energized, it adsorbs the transmission rod to act, enabling the valve plug to open, allowing the air flow to enter the detection pipe from the first joint, driving the mobile reference module to return along the original path in the detection pipe, and realizing the function of the mobile reference module moving back and forth during daily detection, which can be reused. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a plan view of the detection device proposed by the present invention; Figure 2 is a partial structural schematic diagram of the cable body proposed by the present invention; Figure 3 is a front sectional structural schematic diagram of the mobile reference module proposed by the present invention; Figure 4 is Figure 1 an enlarged schematic diagram of the structure at A in Figure 5 is a front sectional structural schematic diagram of the drainage cover proposed by the present invention Figure 1 ; Figure 6 is a front sectional structural schematic diagram of the drainage cover proposed by the present invention Figure 2 .

[0020] In the figure: 1. Installation base; 2. Buoy; 3. Towing cable; 4. Pressure relief valve; 5. Cable body; 6. Detection pipe; 7. End cap; 8. Central rod; 9. Expansion airbag; 10. Drainage cover; 11. First joint; 12. Second joint; 13. Connecting pipe; 14. Valve sleeve; 15. Support sleeve; 16. Transmission rod; 17. Valve plug; 18. Return spring; 19. Plug; 20. Permanent magnet block; 21. First spiral coil; 22. Inductive wire; 23. Second spiral coil; 24. Permanent magnet ring; 25. Underwater sonar detector; 26. Ventilation gap; 27. Mobile reference module. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0022] Referring to Figures 1 - 6 , a cable fault detection device includes an installation base 1 and a buoy 2. A towing cable 3 is connected between the installation base 1 and the buoy 2. A pressure relief valve 4 is arranged inside the buoy 2. A diversion component is arranged inside the installation base 1. The pressure relief valve 4 is communicated with the diversion component through a connecting pipe 13. A cable body 5 laid underwater is fixedly connected with the installation base 1.

[0023] A detection tube 6 is arranged inside the cable body 5. The diversion component is communicated with the inner cavity of the detection tube 6. Specifically, the diversion component includes a drainage cover 10. First joints 11 and second joints 12 are respectively and fixedly installed at both ends of the drainage cover 10. One end of the connecting pipe 13 far from the buoy 2 is communicated with the inner cavity of the drainage cover 10. Both the first joints 11 and the second joints 12 are communicated with the detection tube 6. In detail, a plurality of plugging blocks 19 are arranged inside the detection tube 6. The plurality of plugging blocks 19 divide the inner cavity of the detection tube 6 into multiple sections. The first joints 11 and the second joints 12 are respectively communicated with the inner cavities of the detection tube 6 on both sides of the plugging block 19. For details, see Figure 5 .

[0024] Refer to Figure 5 , a valve sleeve 14 and a support sleeve 15 are fixedly installed inside the drainage cover 10. A transmission rod 16 is slidably installed inside the support sleeve 15. A valve plug 17 is fixedly installed at the end of the transmission rod 16. A return spring 18 is arranged between the support sleeve 15 and the valve plug 17. Under the action of the return spring 18, the valve plug 17 slides into the valve sleeve 14. The valve sleeve 14 is communicated with the mouth of the first joint 11. When the air pressure inside the first joint 11 increases, the valve plug 17 can be pushed open. When the air pressure inside the first joint 11 is relatively small, the valve plug 17 blocks the valve sleeve 14. The opening and closing of the first joint 11 are controlled by the movement of the valve plug 17.

[0025] Refer to Figure 3 , a mobile reference module 27 is arranged inside the detection tube 6. The mobile reference module 27 includes two end caps 7. A center rod 8 is fixedly installed between the two end caps 7. An expansion airbag 9 is sleeved on the surface of the center rod 8; Specifically, an induction wire 22 is embedded inside the end cap 7. An installation ring is fixedly installed inside the end cap 7. A second spiral coil 23 is embedded in the installation ring. The induction wire 22 is electrically connected with the second spiral coil 23. A permanent magnet ring 24 is slidably sleeved on the surface of the center rod 8. The permanent magnet ring 24 contacts the end face of the expansion airbag 9.

[0026] When the cable body 5 is energized, a magnetic field is generated in the cable core of the cable body 5. An air flow is injected into the detection tube 6, which pushes the mobile reference module 27 to move along the inner cavity of the detection tube 6. After the magnetic induction current generated by the induction wire 22 cutting the magnetic field is introduced into the second spiral coil 23, the second spiral coil 23 generates a repulsive or attractive force with the magnetic property of the permanent magnet ring 24. When the permanent magnet ring 24 presses the expansion airbag 9, the internal pressure of the expansion airbag 9 increases and it undergoes an expansion deformation, reducing or bringing into contact the distance between the outer surface of the expansion airbag 9 and the inner wall of the detection tube 6. When the permanent magnet ring 24 moves away from the expansion airbag 9, the expansion airbag 9 naturally contracts, maximizing the distance between the outer surface of the expansion airbag 9 and the inner wall of the detection tube 6 to form a ventilation gap 26.

[0027] When the cable body 5 is de-energized, the magnetic field around the cable core of the cable body 5 disappears, and the volume of the expansion airbag 9 shrinks, creating a ventilation gap 26 between the outer surface of the expansion airbag 9 and the inner wall of the detection tube 6. The inner cavity of the detection tube 6 is connected through the ventilation gap 26, so that under normal conditions, the entire inner cavity of the detection tube 6 is in a connected state.

[0028] During use, the normal state of the cable body 5 is de-energized. Since the inner cavity of the detection tube 6 is connected to the open valve plug 17 through the ventilation gap 26, air is injected into the detection tube 6 to detect the air pressure change inside the detection tube 6 in order to monitor the safety of the entire cable body 5. When the air pressure inside the detection tube 6 changes, the volume of the expansion airbag 9 becomes larger or smaller. Air with a certain air pressure is injected into the detection tube 6 to make the outer surface of the expansion airbag 9 slide into contact with the inner wall of the detection tube 6. If the detection tube 6 is damaged or broken and the internal air is discharged outward, causing an air flow to flow inside the detection tube 6, it drives the mobile reference module 27 to move along the inner cavity of the detection tube 6. When the mobile reference module 27 moves along the inner cavity of the detection tube 6, the movement path of the mobile reference module 27 is detected using the underwater sonar detector 25, as Figure 1 shown.

[0029] Under the condition that the air flow rate injected into the detection tube 6 is constant, by changing the pressure of the permanent magnet ring 24 on the expansion airbag 9, the size of the expansion airbag 9 is adjusted, and using the frictional force between the expansion airbag 9 and the detection tube 6, the movement speed of the mobile reference module 27 is changed to meet the usage requirements of different detections. For example, when the cable body 5 is deformed and there is a narrow area in the inner cavity of the detection tube 6, the narrow area blocks the movement of the mobile reference module 27 from passing through, achieving the effect of detecting the position of the narrow area. Then, the volume of the expansion airbag 9 is reduced to facilitate the mobile reference module 27 to pass through the narrow area for subsequent detection tasks. Or, when the cable body 5 has different degrees of leakage and the air flow input rate is close to the leakage rate, the mobile reference module 27 will stay near the leakage point to better determine the leakage position for convenient repair.

[0030] It should be noted here that the moving speed of the moving reference module 27 is not only controlled by the magnitude of the air flow rate injected into the detection tube 6, but also needs to be controlled by adjusting the current magnitude of the cable core of the lead-in cable body 5. Because if only the flow rate is used to control its moving speed, when the air flow rate in the injection detection tube 6 is large, the air flow discharges from the pressure relief valves 4 at various places, and the moving speed of the moving reference module 27 is too fast to keep the moving reference module 27 near the leakage point. If the air flow rate in the injection detection tube 6 is small, the speed of the moving reference module 27 is too slow, affecting the detection efficiency.

[0031] Taking the complete breakage of a submarine cable as an example, when the cable body 5 breaks, first use a submarine cable pulse tester to preliminarily detect and locate the fault point of the laid submarine cable. The submarine cable pulse tester can accurately measure the length of the submarine cable from the fault point to the signal input point. However, since the cable body 5 is not laid in a straight line, only the range of the fault point can be roughly determined, and the position of the fault point still needs to be accurately detected. The detection device proposed by the present invention sets two buoys 2 in a cable section of a certain length. The repair ship sails to the positions of the two buoys 2 within the range of the fault point, injects gas into the detection tube 6 at the position of the pressure relief valve 4, and drives the moving reference module 27 to move along the detection tube 6. The moving reference module 27 will stop at the breakage of the cable body 5, thereby detecting the specific cable breakage position, such as the burial depth parameter and the offset position of the cable end, guiding divers to search for the cable underwater or guiding the operation of the flushing and suction dredging device, significantly improving the repair efficiency of sudden submarine cable breakage accidents at sea and providing convenience for salvage and repair.

[0032] In this embodiment, a permanent magnet block 20 is embedded inside the transmission rod 16, and a first spiral coil 21 is embedded inside the support sleeve 15. After the first spiral coil 21 is energized, it generates a repulsive or attractive force with the magnetic property of the permanent magnet block 20.

[0033] By setting the drainage cover 10, the opening and closing of the first joint 11 are controlled by the movement of the valve plug 17 inside the drainage cover 10. When injecting gas into the detection tube 6 at the buoy 2, the first joint 11 is closed by using the valve plug 17, so that the air flow in the detection tube 6 enters the detection tube 6 from the second joint 12, and the air flow in the detection tube 6 flows in one direction, thereby achieving the effect of driving the moving reference module 27 to move in a fixed direction. As Figure 1 shown, the moving reference module 27 moves to the right. Since the first spiral coil 21 is arranged inside the support sleeve 15, and the external power supply supplies power to the first spiral coil 21. After the first spiral coil 21 is energized, it adsorbs the transmission rod 16 to act, so that the valve plug 17 is opened, and the air flow enters the detection tube 6 from the first joint 11. As Figure 6As shown, the driving mobile reference module 27 returns along the original path in the detection tube 6, that is, the mobile reference module 27 is moved to the left. During daily detection, the function of the mobile reference module 27 moving back and forth can be realized and reused. It should be noted that a mobile reference module 27 is respectively arranged in the cables of each section, and the mobile reference module 27 cannot enter the drainage cover 10.

[0034] For the detection device proposed by the present invention, by arranging a detection tube 6 in the cable body 5 and arranging a mobile reference module 27 in the detection tube 6, injecting gas into the detection tube 6 to drive the mobile reference module 27 to move along the detection tube 6, and using the underwater sonar detector 25 to detect the moving path of the mobile reference module 27, so as to detect the defective positions of damage, deformation or fracture of the cable body 5. This dynamic detection method has strong recognition, reduces the difficulty of detection and analysis, improves work efficiency, and provides guarantee for the regular inspection and maintenance of submarine cables.

[0035] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitution or change, and should be covered within the protection scope of the present invention.

Claims

1. A cable fault detection device, comprising a mounting base (1) and a buoy (2), characterized in that: A traction rope (3) is connected between the installation base (1) and the buoy (2), a pressure relief valve (4) is provided in the buoy (2), a flow guide component is provided in the installation base (1), the pressure relief valve (4) is connected to the flow guide component via a connecting pipe (13), and a cable body (5) laid underwater is fixedly connected to the installation base (1); A detection tube (6) is arranged in the cable body (5), the flow guide assembly is in communication with the inner cavity of the detection tube (6), and a movable reference module (27) is arranged in the detection tube (6); The mobile reference module (27) comprises two end caps (7), a center rod (8) is fixedly mounted between the two end caps (7), and an expansion airbag (9) is sleeved on the surface of the center rod (8). When the air pressure in the detection tube (6) changes, the volume of the expansion airbag (9) increases or decreases, so that the outer surface of the expansion airbag (9) is in sliding contact with the inner wall of the detection tube (6). When air flows in the detection tube (6), the mobile reference module (27) is driven to move along the inner cavity of the detection tube (6).

2. A cable fault detection device according to claim 1, characterized in that: The flow guide assembly comprises a flow guide cover (10), and a first joint (11) and a second joint (12) are fixedly mounted at both ends of the flow guide cover (10), and an end of the connecting pipe (13) away from the buoy (2) is connected to the inner cavity of the flow guide cover (10), and the first joint (11) and the second joint (12) are both connected to the detection tube (6).

3. A cable fault detection device according to claim 2, characterized in that: A valve sleeve (14) and a support sleeve (15) are fixedly installed in the drainage cover (10), a transmission rod (16) is slidably installed in the support sleeve (15), a valve plug (17) is fixedly installed at the end of the transmission rod (16), and a return spring (18) is arranged between the support sleeve (15) and the valve plug (17). Under the action of the return spring (18), the valve plug (17) is slidably inserted into the valve sleeve (14), the valve sleeve (14) is communicated with the mouth of the first joint (11), and the opening and closing of the first joint (11) is controlled by the movement of the valve plug (17).

4. A cable fault detection device according to claim 3, characterized in that: A plurality of sealing plugs (19) are arranged in the detection tube (6), and the plurality of sealing plugs (19) divide the inner cavity of the detection tube (6) into a plurality of sections. The first connector (11) and the second connector (12) are respectively connected to the inner cavity of the detection tube (6) located on both sides of the sealing plug (19).

5. A cable fault detection device according to claim 4, characterized in that: A permanent magnet block (20) is embedded in the transmission rod (16), and a first spiral coil (21) is embedded in the support sleeve (15). When the first spiral coil (21) is energized, it generates a magnetic repulsive or attractive force with the permanent magnet block (20).

6. A cable fault detection device according to claim 5, characterized in that: An induction wire (22) is embedded in the end cap (7), a mounting ring is fixedly installed in the end cap (7), a second spiral coil (23) is embedded in the mounting ring, the induction wire (22) is electrically connected to the second spiral coil (23), and a permanent magnet ring (24) is slidingly sleeved on the surface of the center rod (8), and the permanent magnet ring (24) is in contact with the end surface of the expansion airbag (9).

7. A cable fault detection device according to claim 6, characterized in that: When the cable body (5) is energized, the cable core of the cable body (5) generates a magnetic field, airflow is injected into the detection tube (6), and the movable reference module (27) is pushed to move along the inner cavity of the detection tube (6). After the magnetic induction current generated by the induction wire (22) cutting the magnetic field is introduced into the second spiral coil (23), the second spiral coil (23) generates a magnetic repulsive or attractive force with the permanent magnet ring (24).

8. A cable fault detection device according to claim 7, characterized in that: When the movable reference module (27) moves along the inner cavity of the detection tube (6), the moving path of the movable reference module (27) is detected by using an underwater sonar detector (25).

9. A cable fault detection device according to claim 6, characterized in that: When the cable body (5) is powered off, the magnetic field around the cable core of the cable body (5) disappears, and the volume of the expansion airbag (9) shrinks, so that a ventilation gap (26) is generated between the outer surface of the expansion airbag (9) and the inner wall of the detection tube (6), and the inner cavity of the detection tube (6) is connected through the ventilation gap (26).

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