Device and method for recovering semi-conductive layer in cable factory joint
By injecting the same internal semiconductor shielding material as the cable body into the semiconducting layer recovery device in the cable factory joint for heating and cross-linking recovery, the problems of pollution and quality in the prior art are solved, and higher quality and stability are achieved The inner semiconducting layer is restored to avoid electric breakdown damage.
Patent Information
- Application Number
- CN202411443227.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-16
- Publication Date
- 2025-01-14
AI Technical Summary
The semiconducting layer recovery process in the joints of the existing cable factory has the risk of pollution, and the defects caused by quality instability and pressure imbalance due to relying on manual operations, such as gaps, pores and mold clamping joints, which are prone to cause breakdown damage.
A semiconductor layer recovery device in the cable factory joint including a shell, a first mold and a curved plate is designed. By injecting the same internal semiconductor shield material as the cable body into the shell, it is used to recover the heat-raising cross-linking by using a heating rod. And vacuum exhaust ensures uniform flow and bonding of materials, reducing the dependence of manual operation.
It significantly reduces the risk of pollution, improves the quality and stability of the semiconductor layer in the joint, avoids electric breakdown damage caused by defects, and achieves a more uniform and reliable recovery of the internal semiconductor layer.
Smart Images
Figure CN119315456A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of power cable accessories, and in particular to a device and method for recovering a semi-conductive layer in a cable factory joint. Background Art
[0002] Prefabricated cable joints cannot be used for submarine cables. In most cases, molded factory joints are required for submarine cables. The production of factory joints includes the restoration of the inner semi-conductive layer.
[0003] The current mainstream process for restoring the inner semi-conductive layer is wrapping, that is, wrapping a special cross-linkable semi-conductive shielding tape around the joint conductor, and restoring the inner semi-conductive layer by heating the matching mold, manually pressing, etc. Although this process mode is simple and easy to operate, it has some obvious defects:
[0004] 1) Although the wrapped semi-conductive shielding tape used is made of the same inner semi-conductive shielding material as the cable body, its production environment and transportation environment cannot meet the corresponding cleanliness requirements, and the tape used for wrapping is inevitably contaminated with dust;
[0005] 2) The wrapping process requires manual operation by professionals. A slight uneven force will cause the corners of the strip to be squeezed to form gaps and pores, which can easily cause local electric field concentration, induce the growth of electric trees, and then cause electrical breakdown and damage to the joint. On the other hand, this process is also extremely dependent on the personal level of the operator, and the quality of the inner semi-conductive layer recovery is unstable.
[0006] 3) The existing matching molds are manually pressed, and the pressure is uneven, which is very likely to cause defects such as mold seams and unfused layers.
[0007] Therefore, those skilled in the art are committed to developing a device and method for recovering the semi-conductive layer in a cable factory joint. Summary of the invention
[0008] In view of the above-mentioned defects in the prior art, the technical problem to be solved by the present invention is to provide a device and method for restoring the semi-conductive layer in a cable factory joint.
[0009] To achieve the above-mentioned purpose, the present invention provides a semi-conductive layer recovery device in a cable factory joint, comprising a shell, a first axially extending through hole is opened in the center of the shell, a plurality of axially extending second through holes are opened around the first through hole, a heating rod is fitted in the second through hole, and a radially extending third through hole is opened on the top of the shell.
[0010] Preferably, the shell includes a first mold and a second mold that fit together up and down, the first mold and the second mold are detachably connected, and a first groove is formed on the inner wall of the first mold, and the first groove is connected to the third through hole.
[0011] Preferably, the first mold is detachably connected to a curved plate, the curved plate cooperates with the inner cavity of the first mold, the curved plate cooperates with the first groove to form an arc-shaped cavity, the curved plate is provided with at least one extrusion channel, and the first groove is connected to the first through hole through the extrusion channel.
[0012] Preferably, a temperature sensing hole is provided on the top of the first mold.
[0013] Preferably, the first mold is provided with at least one positioning ridge, and the second mold is provided with a positioning groove matching with the first ridge.
[0014] Preferably, the first mold, the second mold and the arc plate are all made of highly conductive metal materials.
[0015] Preferably, the first mold, the second mold and the inner wall of the arc-shaped cavity are all attached with a high-temperature resistant release coating.
[0016] Preferably, both ends of the shell are detachably connected with sealing rings.
[0017] The present invention also provides a method for recovering a semi-conductive layer in a cable factory joint, which is accomplished by using any of the above-described devices for recovering a semi-conductive layer in a cable factory joint.
[0018] Preferably, the method further comprises the following steps:
[0019] S1. Pre-treatment of the joint: wrap the semi-conductive nylon tape around the conductor core after welding, grinding and cleaning;
[0020] S2, mold assembly, placing the second mold just below the conductor core connector, using the auxiliary alignment rubber pressing sheet to wrap the conductor core connector, adjusting the height position of the second mold until the second mold is in close contact with the auxiliary alignment rubber pressing sheet, pulling out the auxiliary alignment rubber pressing sheet, fixing the position of the second mold, placing the arc plate and the first mold above the conductor core connector in sequence, and then fastening the molds together;
[0021] S3, shell pretreatment, when the shell is assembled in place, one end of the shell and the third through hole are plugged and sealed, and the other end of the shell is vacuumed using an exhaust pipe. After the vacuum treatment is completed, the other end is also plugged;
[0022] S4, preheating, preheating the mold;
[0023] S5, heating and extruding, injecting molten inner semi-conductive shielding material of the same material as the inner semi-conductive layer of the cable body into the third through hole;
[0024] S6, heat preservation, stabilize the mold temperature at 170℃ and maintain it for 1h~1.5h;
[0025] S7, cooling and demolding, after the shell is naturally cooled to room temperature, the shell and the curved plate are removed;
[0026] S8, surface modification, polishing and grinding the restored surface of the semi-conductive layer.
[0027] The beneficial effects of the present invention are as follows: the present invention arranges a shell, and then extrude the same inner semi-conductive shielding material as the cable body into the shell, thereby completing the temperature rise cross-linking recovery in the shell, greatly reducing the risk of contamination of the prefabricated inner semi-conductive tape used for traditional wrapping recovery during production and transportation, improving the quality of the finished product, and the present invention has a simple structure and is easy to promote.
[0028] In addition, the transition between the semi-conductive recovery layer in the joint prepared by the method and the semi-conductive layer in the cable body is smooth and uniform, and the fusion is good, avoiding the formation of defects such as gaps, pores, mold seams, and unfused layers, reducing the risk of electrical breakdown damage to the joint due to local electric field concentration in the defects, and the recovery quality is stable and reliable. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 It is a structural schematic diagram of a specific implementation mode of the present invention.
[0030] Figure 2 It is a front view of a specific embodiment of the present invention.
[0031] Figure 3 yes Figure 2 Schematic diagram of the cross-section structure of AA.
[0032] 1. Shell; 11. First mold; 11a. First groove; 11b. Temperature sensing hole; 11c. Positioning ridge; 12. Second mold; 12a. Positioning groove; 2. First through hole; 3. Second through hole; 4. Heating rod; 5. Third through hole; 6. Arc plate; 61. Extrusion channel. DETAILED DESCRIPTION
[0033] The present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that in the description of the present invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific manner, and therefore cannot be understood as limiting the present invention. The terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.
[0034] like Figure 1-3As shown, a device for recovering the inner semi-conductive layer of a cable factory joint comprises a shell 1, a first through hole 2 extending axially and horizontally is opened in the center of the shell 1, the first through hole 2 is a wire hole, which is mainly used to accommodate and place the conductor core (the diameter of the first through hole 2 ≈ the diameter of the conductor core + 5.5-6 mm), and a plurality of second through holes 3 extending axially are opened around the first through hole 2. In this embodiment, the second through holes 3 are arranged in four groups, which are respectively located at the four corners of the shell 1, and a heating rod 4 is matched in the second through hole 3. The heating rod 4 is arranged to meet the heating and insulation requirements for the recovery of the inner semi-conductive layer, so as to ensure that the molten inner semi-conductive material has a good flow state in the shell 1, and a third through hole 5 extending radially is opened in the center of the top of the shell 1. The third through hole 5 is cylindrical and mainly provides a channel for injection molding.
[0035] In this embodiment: the shell 1 includes a first mold 11 and a second mold 12 that fit together in an upper and lower manner. The first mold 11 and the second mold 12 are detachably connected. In this embodiment, the detachable connection is a bolt connection, which may be replaced by bonding, clamping, etc. in other embodiments. A first groove 11a is opened on the inner wall of the first mold 11, and the first groove 11a is connected to the third through hole 5. The molten inner semi-conductive shielding material can flow into the first groove 11a along the third through hole 5.
[0036] In this embodiment: the first mold 11 is detachably connected with an arc plate 6. In this embodiment, the detachable connection is a snap connection. In other embodiments, threaded connection or bonding can be used instead. The arc plate 6 is matched with the inner cavity of the first mold 11, and the matching gap is 0.01mm~0.02mm. The shape of the arc plate 6 is matched with the shape of the inner cavity of the first mold 11. The arc plate 6 and the first groove 11a are matched to form an arc cavity. At least one extrusion channel 61 is opened on the arc plate 6. In this embodiment, two extrusion channels 61 are set, and the two extrusion channels 61 are arranged at intervals on the arc plate 6. The first groove 11a is connected with the first through hole 2 through the extrusion channel 61. The molten inner semi-conductive material is injected from the third through hole 5, and is evenly extruded from the extrusion channel 61 after passing through the first groove 11a.
[0037] In this embodiment: a temperature sensing hole 11b is set on the top of the first mold 11, which is used to detect the internal temperature of the mold in real time during the recovery process of the inner semi-conductive layer, and provide temperature support for heating and insulation operations. The first mold 11 is provided with at least one positioning ridge 11c, and the second mold 12 is provided with a positioning groove 12a matching the first ridge. In this embodiment, the positioning ridge 11c and the positioning groove 12a are set in two groups, which are respectively located on both sides of the length direction of the first mold 11 and the second mold 12, and extend axially along the first mold 11. The positioning ridge 11c and the positioning groove 12a can assist in fitting the first mold 11 and the second mold 12.
[0038] In this embodiment: the first mold 11, the second mold 12 and the arc plate 6 are all made of highly conductive metal materials. In this embodiment, the highly conductive metal material is copper. In other embodiments, silver, gold and other materials with equivalent effects can be used. The first mold 11, the second mold 12 and the inner wall of the arc cavity are all attached with high-temperature resistant demoulding coatings. By setting the high-temperature resistant demoulding coating, the adhesion between the molten inner semi-conductive shielding material and the inner walls is reduced. In this embodiment, the high-temperature resistant demoulding coating is a polytetrafluoroethylene demoulding coating. In addition, both ends of the shell 1 are detachably connected with sealing rings (not shown in the figure). In this embodiment, the detachable connection is a snap-on connection. By setting sealing rings at both ends of the shell 1, the air tightness of the device can be effectively improved, and dust, impurities, etc. can be reduced from entering the shell 1 to affect the quality of the finished product. Since the recovery amount of the inner semi-conductive layer is small and the exhaust volume is not large, the device directly uses the end faces on both sides of the shell 1 for exhaust and discharge, thereby reducing sample molding defects.
[0039] During use: place the second mold 12 under the conductor core joint, then place the arc plate 6 and the first mold 11 above the conductor core joint in sequence, fix the first mold 11 and the second mold 12 in connection, inject the molten inner semi-conductive shielding material from the third through hole 5 into the arc space, the molten inner semi-conductive shielding material flows out evenly along the extrusion channel 61 in the arc space, thereby restoring the conductor core joint. The present invention extrude the same inner semi-conductive shielding material as the cable body for temperature rise cross-linking restoration, thereby greatly reducing the risk of contamination during the production and transportation of the prefabricated inner semi-conductive tape used for traditional wrapping restoration.
[0040] The present invention also provides a method for recovering a semi-conductive layer in a cable factory joint, which is accomplished by using the above-mentioned device for recovering a semi-conductive layer in a cable factory joint.
[0041] The specific steps include:
[0042] S1. Pre-treatment of the joint: wrap 1 to 2 layers of semi-conductive nylon tape around the conductor core after welding, grinding and cleaning, with an overlap rate of 20% to 50%.
[0043] S2. Assemble the molds. Place the second mold 12 directly below the conductor core connector. Use an auxiliary alignment rubber pressing sheet (not shown in the figure, with a thickness of 3 mm) to evenly wrap the connector and at least completely wrap the lower half of the connector. Slowly raise the adjustable base (not shown in the figure) to adjust the height of the second mold 12 until the second mold 12 is in close contact with the auxiliary alignment rubber pressing sheet. Pull out the auxiliary alignment rubber pressing sheet, fix the position of the second mold 12, place the arc plate 6 and the first mold 11 above the conductor core connector in sequence, align the positioning ridge 11c on the first mold 11 with the positioning groove 12a on the second mold 12, and then tighten the molds together.
[0044] S3, pretreatment of the shell 1. After the shell 1 is assembled in place, a sealing ring is used to plug and seal one end of the shell 1 and the third through hole 5. A vacuum pipe is used at the other end of the shell 1 to vacuum the inside of the shell 1. After the vacuum treatment is completed, a sealing ring is used to plug and seal the end as well. This step can greatly improve the airtightness of the device and reduce the entry of dust, impurities, etc. into the shell 1.
[0045] S4, preheating, start the heating rod 4 to preheat the mold to 120°C.
[0046] S5. Heat and extrude, and inject molten inner semi-conductive shielding material of the same material as the inner semi-conductive layer of the cable body into the third through hole 5. The molten inner semi-conductive shielding material flows into the arc-shaped cavity along the third through hole 5, and overflows along the extrusion channel 61 in the arc-shaped cavity. After two minutes of extrusion, remove the rubber sealing rings at both ends of the device, and continue to inject until the inner semi-conductive shielding material begins to overflow from both ends of the shell 1. Use silk cloth to seal both ends of the shell 1, and continue to inject for one minute to ensure that the interior is completely filled.
[0047] S6, heat preservation, start the heating rod 4 to stabilize the temperature in the mold at 170°C and maintain it for 1h to 1.5h, so that the injected semi-conductive shielding material and the inner semi-conductive layer of the connector body are fully cross-linked and the interface is integrated.
[0048] S7, cooling and demoulding. After the heat preservation is completed, the shell 1 is naturally cooled to room temperature, and then the shell 1 and the curved plate 6 are removed.
[0049] S7. Surface modification: polish and grind the restored surface of the semi-conductive layer, use a special curved scraper to roughly repair the restored surface of the inner semi-conductive layer, and use 400, 600 and 1000 sandpapers and silk cloth to grind and polish in turn to ensure that the generated inner semi-conductive restored interface is smooth without protrusions or depressions.
[0050] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.
Claims
1. A device for recovering the semi-conductive layer in a cable factory joint, characterized by: The invention comprises a shell (1), wherein a first through hole (2) extending axially is formed in the center of the shell (1), a plurality of second through holes (3) extending axially are formed around the first through hole (2), a heating rod (4) is fitted in the second through hole (3), and a third through hole (5) extending radially is formed at the top of the shell (1).
2. The device for recovering the semi-conductive layer in the cable factory joint as claimed in claim 1, characterized in that: The housing (1) comprises a first mold (11) and a second mold (12) which fit together at the top and the bottom. The first mold (11) and the second mold (12) are detachably connected. A first groove (11a) is formed on the inner wall of the first mold (11). The first groove (11a) is connected to the third through hole (5).
3. The device for recovering the semi-conductive layer in the cable factory joint as claimed in claim 1, characterized in that: The first mold (11) is detachably connected to a curved plate (6), the curved plate (6) cooperates with the inner cavity of the first mold (11), the curved plate (6) cooperates with the first groove (11a) to form an arc-shaped cavity, the curved plate (6) is provided with at least one extrusion channel (61), and the first groove (11a) is connected to the first through hole (2) via the extrusion channel (61).
4. The device for recovering the semi-conductive layer in the cable factory joint as claimed in claim 2, characterized in that: A temperature sensing hole (11b) is provided on the top of the first mold (11).
5. The device for recovering the semi-conductive layer in the cable factory joint as claimed in claim 2, characterized in that: The first mold (11) is provided with at least one positioning ridge (11c), and the second mold (12) is provided with a positioning groove (12a) matching the first ridge (11c).
6. The device for recovering the semi-conductive layer in the cable factory joint as claimed in claim 3, characterized in that: The first mold (11), the second mold (12) and the arc-shaped plate (6) are all made of highly conductive metal materials.
7. The device for recovering the semi-conductive layer in the cable factory joint as claimed in claim 6, characterized in that: The first mold (11), the second mold (12) and the inner wall of the arc-shaped cavity are all attached with a high-temperature resistant demoulding coating.
8. The device for recovering the semi-conductive layer in a cable factory joint as claimed in claim 1, characterized in that: Both ends of the housing (1) are detachably connected with sealing rings.
9. A method for restoring the semi-conductive layer in a cable factory joint, characterized in that: This is accomplished by using a device for recovering a semi-conductive layer in a cable factory joint as described in any one of claims 1-8.
10. The method for restoring the semi-conductive layer in a cable factory joint as claimed in claim 9, characterized in that: The following steps are involved: S1. Pre-treatment of the joint: wrap the semi-conductive nylon tape around the conductor core after welding, grinding and cleaning; S2, assembling the mold, placing the second mold (12) directly below the conductor wire core connector, using the auxiliary alignment rubber pressing sheet to wrap the conductor wire core connector, adjusting the height position of the second mold (12) until the second mold (12) is in close contact with the auxiliary alignment rubber pressing sheet, pulling out the auxiliary alignment rubber pressing sheet, fixing the position of the second mold (12), placing the arc plate (6) and the first mold (11) above the conductor wire core connector in sequence, and then fastening the molds together; S3, pre-treatment of the shell (1), when the shell (1) is assembled in place, one end of the shell (1) and the third through hole (5) are sealed with a plug, and a vacuum treatment is performed on the inside of the shell (1) using a vacuum pipe at the other end of the shell (1). After the vacuum treatment is completed, the other end is also sealed with a plug; S4, preheating, preheating the mold; S5, heating and extruding, injecting molten inner semi-conductive shielding material of the same material as the inner semi-conductive layer of the cable body into the third through hole (5); S6, keep the mold temperature stable at 170°C and maintain for 1h to 1.5h; S7, cooling and demoulding, after the shell (1) is naturally cooled to room temperature, the shell (1) and the curved plate (6) are removed; S8, surface modification, polishing and grinding the restored surface of the semi-conductive layer.