Oil-filled cable terminal plugging structure and installation method thereof

Abstract

An oil-filled cable terminal plugging structure and an installation method thereof, relating to the field of cable plugging technology. The invention comprises an outer sleeve, the outer sleeve is a hollow structure with one side open and the other side closed, an inner cone is embedded inside the outer sleeve, the inner cone is a hollow structure with one side open and the other side closed, an inner plug is arranged inside the inner cone, the central area of ​​one side of the inner plug extends outward to form a cone plug, and the cone plug matches and corresponds to the oil guide pipe. The invention achieves minimization of damage to submarine oil-filled cables, minimization of seawater pollution and economic losses, and maximization of safety of submarine cables.

Description

Technical Field

[0001] The invention relates to the technical field of cable plugging, and in particular to an oil-filled cable terminal plugging structure and an installation method thereof. Background Art

[0002] There is an oil pump station at each end of the submarine oil-filled cable. The two pump station systems are configured exactly the same. It provides guarantee for the oil supply of the submarine cable under normal and abnormal conditions. At the same time, it can monitor the oil flow and oil pressure of the oil-filled cable in real time, and grasp the operating status of the submarine cable from the side. In order to ensure the stable operation of the submarine oil-filled cable, it is necessary to use a sealing structure to seal the submarine oil-filled cable when it is damaged and leaking oil, so as to prevent the leakage of insulating oil in the submarine cable oil-filled pipe and the infiltration of seawater. However, the submarine cable is located on the seabed, and the force of seawater will affect the sealing structure. The sealing mechanism in the prior art is likely to loosen in this environment and affect the sealing effect, and may also cause damage to the sealing structure. Summary of the invention

[0003] The purpose of the present invention is to solve the shortcomings of the prior art and to propose an oil-filled cable terminal plugging structure and an installation method thereof.

[0004] In order to achieve the above purpose, the technical solution adopted by the present invention is: a sealing structure for an oil-filled cable terminal, an oil guide tube is provided at the center of the oil-filled cable, an outer sheath is provided at the outermost layer of the oil-filled cable, the sealing structure includes an inner plug, an inner cone and an outer sleeve which are sequentially arranged from the inside to the outside, an inner plug is provided inside the inner cone, and the central area of ​​one side surface of the inner plug extends outward to form a cone plug, the cone plug matches the inner diameter of the oil guide tube, the inner cone is a hollow structure with one side open and the other side closed, and the outer sleeve is a hollow structure with one side open and the other side closed.

[0005] Furthermore, the inner cone part includes a frustum part and a cylinder part connected in sequence, the frustum part is embedded in the outer sleeve, one side of the cylinder part extends into the outer sleeve and is connected to the frustum part, and the other side of the cylindrical part extends to the outside of the outer sleeve.

[0006] Furthermore, the outer sleeve is provided with an accommodating cavity inside, and the accommodating cavity matches and corresponds to the shape and size of the inner cone located in the outer sleeve.

[0007] Furthermore, a clamping outer tube is sleeved on the outer side of the cylindrical component, and the tube opening of the clamping outer tube away from the outer sleeve side protrudes toward the central axis direction of the clamping outer tube to form a bayonet, the inner diameter of the bayonet is the same as the inner diameter of the cylindrical component, and the thickness of the bayonet is the same as the thickness of the side wall of the cylindrical component.

[0008] Furthermore, a second sealing ring is provided between the inner wall of the bayonet and the port of the cylindrical component.

[0009] Furthermore, a first sealing ring is provided between the contact surface between the inner plug and the cable, and a first elastic gasket is provided between the other side surface of the inner plug and the inner wall of the closed side of the truncated cone component.

[0010] Furthermore, a second elastic gasket is provided between the outer wall of the closed side of the truncated cone component and the inner wall of the closed side of the outer sleeve.

[0011] Furthermore, the blocking structure includes a hollow sampling tube, one side of which passes through the outer sleeve, the inner cone and the inner plug in sequence and extends into the oil guide tube.

[0012] Furthermore, the blocking structure includes a detection device, which includes a detection probe and a detection module. The detection probe is located at the end of the vertebral plug.

[0013] The second aspect of the present invention provides a method for installing an oil-filled cable terminal plugging structure, which is implemented based on the oil-filled cable terminal plugging structure described in the first aspect of the present invention and includes the following steps:

[0014] S1. Insert the cone plug of the inner plug into the oil guide pipe of the oil-filled cable and connect the two by welding. Install a first sealing ring at the connection surface between the inner plug and the cable, and install a first elastic gasket on the other side of the inner plug.

[0015] S2, sleeve the outer sleeve on the outside of the truncated cone component of the inner cone, and place a second elastic gasket between the bottom surface of the truncated cone component and the inner bottom surface of the outer sleeve;

[0016] S3, a second sealing ring is arranged between the inner cone and the inner wall of the outer sleeve bayonet, and a flange plate is fixed to the outer wall of the closed side of the outer sleeve by bolts;

[0017] S4. The clamping outer tube connects the cylinder of the inner cone and the metal protective layer of the oil-filled cable, and the clamping outer tube is provided with screw holes, and the two clamping outer tubes are fixed to the inner cone and the oil-filled cable by screws.

[0018] Furthermore, detection information is collected through a detection probe, and a sample of the insulating oil in the oil-filled pipe is obtained through a sampling tube.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention achieves the sealing of the oil-filled cable oil guide pipe by an inner plug. However, due to the small size of the inner plug and the certain pressure of the insulating oil in the oil guide pipe, in order to maintain a stable connection between the inner plug and the oil guide pipe, an inner cone is combined with an outer sleeve to fix the inner plug. A cone structure that cooperates with the outer sleeve is adopted. When the outer sleeve is subjected to external force, the cone structure makes the two parts more tightly connected.

[0021] 2. The present invention achieves the plugging of submarine oil-filled cables. The present invention can ensure that the submarine cable is damaged in an emergency situation with minimal damage to the oil-filled cable, thereby preventing seawater from entering to avoid large-scale damage to the submarine cable, and at the same time preventing a large amount of cable oil from flowing into the sea, causing seawater pollution and economic losses, and can also reduce the penetration of seawater into the oil-paper insulation of the oil-filled cable, leaving safety hazards, and also provide time for subsequent connections.

[0022] 3. The present invention expands the function of the axial opening of the end sealing component to form an interface for oil pressure monitoring and oil sampling, which can be connected to a corresponding pressure instrument, a monitoring terminal or a sampling device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of an oil-filled cable terminal plugging structure according to a specific embodiment of the present invention;

[0024] Figure 2 for Figure 1 Left view of;

[0025] Figure 3 for Figure 1 A top view of

[0026] Figure 4 for Figure 1 Rear view of

[0027] Figure 5 For along Figure 2 Sectional view of the AA section line;

[0028] In the figure: 1-oil-filled cable, 2-inner plug, 3-first sealing ring, 4-first elastic gasket, 5-inner cone, 6-second sealing ring, 7-second elastic gasket, 8-outer sleeve, 9-flange plate, 10-clamping outer tube, 11-oil guide tube, 12-conical plug. DETAILED DESCRIPTION

[0029] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations.

[0030] like Figure 1-5The terminal sealing structure of an oil-filled cable 1 is shown, wherein the oil-filled cable 1 comprises an oil guide pipe, a conductor, a main insulating layer, a metal protective layer and an outer layer from the inside to the outside, and the oil guide pipe is filled with insulating oil with a certain pressure.

[0031] In a specific embodiment, the sealing structure is a hollow structure with one side open and the other side closed, including an inner plug 2, an inner cone 5 and an outer sleeve 8 which are nested and installed in sequence from the inside to the outside. One end of the oil-filled cable 1 extends into the open side of the sealing structure and fits tightly against the inner wall of the closed side of the sealing structure, thereby sealing the oil guide pipe in the oil-filled cable 1, repairing the oil-filled cable, and preventing the intrusion of seawater and the leakage of insulating oil in the oil guide pipe 11.

[0032] like Figure 5 As shown, the central area of ​​one side of the inner plug 2 extends outward to form a cone plug 12, and the cone plug matches and corresponds to the oil guide tube. The cone plug 12 is inserted into the oil guide tube 11 to achieve a blocking effect.

[0033] The inner cone 5 is a hollow structure with one side open and the other side closed, and the outer sleeve 8 is also a hollow structure with one side open and the other side closed, and the outer sleeve 8 has a cylindrical structure on the outside. During use, the specific structure of the outer sleeve 8 can be adjusted as needed, for example, it can be in the shape of a quadrangular prism or a hexagonal prism.

[0034] The fixed connection between the inner plug 2 and the oil-filled cable 1 is achieved by the inner cone part 5 and the outer sleeve 8. In order to further enhance the stability between the inner cone part 5 and the outer sleeve 8, the inner cone part 5 includes a frustum part and a cylinder part. The frustum part is embedded in the outer sleeve 8, one side of the cylinder part extends into the outer sleeve and is connected with the frustum part, and the other side of the cylinder part extends to the outside of the outer sleeve 8. The frustum part and the cylindrical part can be an integrated structure or a detachable half structure; the inner plug 2 is located in the frustum part, and the frustum part covers the inner plug 2 to prevent the inner plug 2 from being separated from the oil-filled cable. In addition, in order to achieve complete blocking of the oil-filled cable 1, the inner plug 2 needs to be larger than the outer diameter of the oil-filled cable. The frustum part can accommodate the difference in outer diameters between the oil-filled cable 1 and the inner plug 2. The edge of the inner plug is embedded in the inner wall of the frustum part to achieve fixed connection between the inner plug 2 and the oil-filled cable 1. The truncated cone component can be fixedly engaged with the inner wall of the outer sleeve 8, further improving the overall stability of the blocking structure.

[0035] Since the connection between the truncated cone component and the cylindrical component is the connection transition point of the two shapes, the structural stability is relatively poor. Therefore, the truncated cone component and part of the cylindrical component are located in the outer sleeve 8, so that the structural weak positions of the inner cone 5 are all located within the protection range of the outer sleeve, thereby enhancing the overall impact resistance of the sealing structure.

[0036] Correspondingly, the outer sleeve 8 is provided with an accommodating cavity inside, and the accommodating cavity corresponds to the size and structure of the truncated cone component and part of the cylindrical component located inside the titanium sleeve 8. The inner cone 5 is stably embedded in the outer sleeve 8 through the accommodating cavity and will not fall out. The oil-filled cable 1 is clamped by the cylindrical component, and the central axis of the oil guide pipe is coincident with the central axis of the cone plug of the inner plug 2 or maintained within a suitable angle range, thereby preventing leakage of insulating oil.

[0037] A flange plate 9 is provided on the outer wall of the closed side of the outer sleeve 8, and the flange plate 9 is fixed to the outer sleeve by screws. On the one hand, the strength of the outer sleeve 8 is enhanced. On the other hand, when other additional structures are added to the outside of the outer sleeve 8, they can be directly installed on the flange plate 9, thereby ensuring the stability and integrity of the sealing structure.

[0038] In order to further maintain the position stability of the oil-filled cable 1 along the central axis of the cable, a clamping outer tube 10 is sleeved on the outer side of the cylindrical component, and the pipe opening of the clamping outer tube 10 away from the outer sleeve 8 protrudes toward the central axis of the clamping outer tube 10 to form a bayonet, and the inner diameter of the bayonet is the same as the inner diameter of the cylindrical component. The bayonet can not only further clamp the oil-filled cable 1, but also keep the relative positions of the inner cone 5 and the outer sleeve 8 fixed through the bayonet.

[0039] In order to further ensure the sealing performance and shock absorption performance, a second sealing ring 6 is provided between the inner wall of the bayonet and the port of the cylindrical component, a first sealing ring 3 is provided between the contact surface of the inner plug 2 and the cable, and a first elastic gasket 4 is provided between the inner plug 2 and the bottom surface of the truncated cone component. A second elastic gasket 7 is provided between the truncated cone and the outer sleeve 8.

[0040] In order to facilitate installation and disassembly on the one hand, and to facilitate processing on the other hand, the inner cone 5, the outer sleeve 8 and the clamping outer tube 10 are all Hough structures, which simplifies the plugging process of the submarine cable.

[0041] The sealing effect of the oil-filled cable is mainly reflected in whether there is leakage of internal insulating oil and infiltration of external seawater. Usually, the working position of the oil-filled cable is on the seabed, and it is difficult to detect a small amount of insulating oil leakage. In order to solve this problem, a hollow sampling tube is arranged in the sealing structure, and one side of the sampling tube passes through the outer sleeve, the inner cone and the inner plug in sequence and extends into the oil guide pipe. By making axial holes in the outer sleeve, the inner cone and the inner plug and adding the sampling tube, the insulating oil in the oil guide pipe at the sealing structure can be sampled in time, and it can be judged in time whether the current sealing effect meets the requirements according to the sampling results. When the sealing requirements are not met, adjustments can be made in time.

[0042] Since the plugging structure is a remedial measure for the oil-filled cable, it is necessary to detect relevant parameters of the plugging position, such as the pressure of the insulating oil, etc. For this purpose, the plugging structure is provided with a detection device, which includes a detection probe (existing sensing detection devices such as pressure sensors) and a detection module. The detection probe is located at the end of the cone plug. The detection module can use an existing signal receiving chip to upload the detection data to the remote monitoring terminal, and the remote monitoring terminal analyzes the detection data.

[0043] In a specific embodiment, a method for installing a terminal plugging structure of an oil-filled cable 1 is implemented based on the above-mentioned terminal plugging structure of the oil-filled cable 1, and includes the following steps:

[0044] S1. Insert the cone plug of the inner plug 2 into the oil guide pipe of the oil-filled cable 1, and connect the two by welding. Install the first sealing ring 3 at the connection surface between the inner plug 2 and the cable, and install the first elastic gasket 4 on the other side of the inner plug 2;

[0045] S2, sleeve the outer sleeve 8 on the outside of the truncated cone component of the inner cone 5, and place a second elastic gasket 7 between the bottom surface of the truncated cone component and the inner bottom surface of the outer sleeve 8;

[0046] S3, a second sealing ring 6 is arranged between the inner cone 5 and the inner side wall of the bayonet of the outer sleeve 8, and a flange plate 9 is fixed on the closed side of the outer sleeve 8 by bolts;

[0047] S4. The clamping outer tube 10 connects the cylinder of the inner cone 5 and the metal protective layer of the oil-filled cable 1, and the clamping outer tube 10 is provided with screw holes, and the two clamping outer tubes 10 are fixed to the inner cone 5 and the oil-filled cable 1 by screws.

[0048] S5. Collect detection information through the detection probe, and obtain the insulating oil sample in the oil-filled pipe through the sampling tube.

[0049] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A plugging structure for an oil-filled cable terminal, wherein an oil guide pipe is provided at the center of the oil-filled cable, and an outer sheath is provided at the outermost layer of the oil-filled cable, characterized in that: The plugging structure comprises an inner plug, an inner cone and an outer sleeve which are sequentially sleeved from the inside to the outside, wherein the inner plug is arranged inside the inner cone, and the central area of ​​one side of the inner plug extends outward to form a cone plug, and the cone plug matches and corresponds to the inner diameter of the oil guide pipe, the inner cone is a hollow structure with one side open and the other side closed, and the outer sleeve is a hollow structure with one side open and the other side closed; The inner cone part includes a frustum part and a cylinder part connected in sequence, the frustum part is embedded in the outer sleeve, one side of the cylindrical part extends into the outer sleeve and is connected to the frustum part, and the other side of the cylindrical part extends to the outside of the outer sleeve; a clamping outer tube is sleeved on the outer side of the cylindrical part, and the tube opening of the clamping outer tube away from the outer sleeve side protrudes toward the central axis direction of the clamping outer tube to form a bayonet, the inner diameter of the bayonet is the same as the inner diameter of the cylindrical part, and the thickness of the bayonet is the same as the thickness of the side wall of the cylindrical part; a second sealing ring is passed between the inner wall of the bayonet and the port of the cylindrical part.

2. The oil-filled cable terminal sealing structure according to claim 1, characterized in that: A first sealing ring is provided between the contact surface of the inner plug and the cable, and a first elastic gasket is provided between the other side surface of the inner plug and the inner wall of the closed side of the truncated cone component.

3. The oil-filled cable terminal sealing structure according to claim 1, characterized in that: A second elastic gasket is provided between the outer wall of the closed side of the truncated cone component and the inner wall of the closed side of the outer sleeve.

4. The oil-filled cable terminal sealing structure according to claim 1, characterized in that: The blocking structure comprises a hollow sampling tube, one side of which passes through an outer sleeve, an inner cone and an inner plug in sequence and extends into the oil guide tube.

5. The oil-filled cable terminal sealing structure according to claim 1, characterized in that: The blocking structure comprises a detection device, which comprises a detection probe and a detection module. The detection probe is located at the end of the cone plug.

6. A method for installing an oil-filled cable terminal plugging structure, characterized in that: The oil-filled cable terminal sealing structure according to any one of claims 1 to 5 is implemented, comprising the following steps: S1. Insert the cone plug of the inner plug into the oil guide pipe of the oil-filled cable and connect the two by welding. Install a first sealing ring at the connection surface between the inner plug and the cable, and install a first elastic gasket on the other side of the inner plug. S2, sleeve the outer sleeve on the outside of the truncated cone component of the inner cone, and place a second elastic gasket between the bottom surface of the truncated cone component and the inner bottom surface of the outer sleeve; S3, a second sealing ring is arranged between the inner cone and the inner side wall of the clamping outer tube, and a flange plate is fixed to the outer wall of the closed side of the outer sleeve by bolts; S4. The clamping outer tube connects the cylindrical part of the inner cone and the metal protective layer of the oil-filled cable, and the clamping outer tube is provided with screw holes, and the two clamping outer tubes are fixed to the inner cone and the oil-filled cable by screws.

7. The method for installing an oil-filled cable terminal plugging structure according to claim 6, characterized in that: The detection information is collected through the detection probe, and the insulating oil sample in the oil guide pipe is obtained through the sampling tube.

Images