Copper wire shielding structure single-core sensing cable and forming process

Abstract

The application discloses a copper wire shielding structure single-core sensing cable and a forming process, relates to the technical field of cable production, and proposes a protection structure for a sensing unit in a single-core sensing cable. The essence is that a second supporting conductor with a slightly larger diameter is placed on both sides of the sensing unit, and the remaining periphery is based on a plurality of copper wires with different diameters, which are arranged in gaps along the periphery of the conductor insulation layer and maintain the compact arrangement of the second supporting conductor and the sensing unit. The purpose is to support and protect the sensing unit, avoid the influence of pressure deformation on the sensing effect during the process of laying and running, and as much as possible maintain the overall roundness of the cable. The semi-conductive water-blocking tape plays a water-blocking effect at the gap, and the sensing unit and the second supporting conductors on both sides bear the external radial pressure, avoiding the direct action of the pressure on the sensing unit. The forming process of the overall sensing cable is optimized and improved, and is used for maintaining the wire arrangement mode of the shielding copper wire, the first supporting conductor, the second supporting conductor and the sensing unit during the forming process.

Description

Technical Field

[0001] This invention relates to the field of cable manufacturing technology, specifically to a single-core sensing cable with copper wire shielding and its forming process. Background Technology

[0002] Sensing cables are cables with added sensing units on the basis of conventional cable structures. Taking the relevant content mentioned in patent documents such as CN110517811A and CN117524573A as examples, their essence is to use optical fiber as a signal transmission structure to provide real-time feedback of electrical signals generated by temperature changes. For reference, see the relevant content mentioned in CN106981326A.

[0003] Single-core cables are made by extrusion or sheathing a single copper conductor. Because optical fibers (the essence of sensing units) are brittle / flexible materials, the deformation caused by pressure during their manufacturing, laying, and operation directly affects their operating state, such as fiber breakage. It should also be noted that, taking the one-time molding process as an example, semiconducting resistive water tape is a flexible material and does not provide sufficient protection for optical fibers, so there is still a risk of deformation under pressure.

[0004] This application proposes a solution to this problem. Summary of the Invention

[0005] The purpose of this invention is to provide a copper wire shielded single-core sensing cable and its forming process. For single-core sensing cables, since the key structure of the internal optical fiber is a flexible material, it is subjected to pressure during cable manufacturing, laying, and operation, which causes local deformation. This directly affects the sensing effect and service life of the optical fiber, and may even cause the sensing capability to be lost due to the direct breakage of the optical fiber.

[0006] The objective of this invention can be achieved through the following technical solution: a copper wire shielded single-core sensing cable, wherein the single-core sensing cable is machined based on cable shielding armor, and the single-core sensing cable includes a copper conductor assembly, an inner insulation layer and a semi-conductive resistive water tape, wherein a copper wire shielding structure layer is provided between the semi-conductive resistive water tape and the inner insulation layer, wherein the copper wire shielding structure layer includes a shielding gap, a second supporting conductor, a shielding copper wire and a first supporting conductor, and one or more sensing units are provided in the copper wire shielding structure layer;

[0007] The sensing unit is composed of a metal protective tube and a grating optical fiber. The second support conductor, the shielding copper wire and the first support conductor are arranged along the length of the copper conductor assembly, and the second support conductor is located on both sides of the sensing unit. The shielding copper wire and the first support conductor are distributed in a ring array along the center point of the copper conductor assembly.

[0008] The diameters of the second supporting conductor and the first supporting conductor are larger than the outer diameter of the metal protective tube, and the diameter of the shielding copper wire is smaller than the diameters of the second supporting conductor, the first supporting conductor, and the metal protective tube.

[0009] The configuration is further defined as follows: the inner insulating layer is positioned between the copper conductor assembly and the copper wire shielding structure layer; the semiconducting resistive water tape is positioned at the outermost layer of the single-core sensing cable; and the gap between the second supporting conductor, the shielding copper wire, and the first supporting conductor forms a shielding gap.

[0010] The shielding copper wire is further configured such that it is located on both sides of the first supporting conductor, and the distance between the center point of the shielding copper wire and the center point of the copper conductor assembly is less than the distance between the center point of the first supporting conductor and the center point of the copper conductor assembly; the second supporting conductor is tangent to the metal protective tube in the sensing unit.

[0011] Furthermore, the distance between the center point of the first supporting conductor and the center point of the copper conductor assembly is greater than the distance between the center point of the second supporting conductor and the center point of the copper conductor assembly.

[0012] The forming process includes raw material preparation, stranding and forming, copper wire wiring and semiconducting resistive water tape wrapping. The raw material preparation step yields metal shielding wire, optical fiber sensing unit and semiconducting resistive water tape. In the stranding and forming step, the sensing unit is arranged with the second support conductor, shielding copper wire and the first support conductor, and stranded to obtain a shielded sensing structure layer.

[0013] The copper wire cabling reinforcement step uses a splitter kit, which lays a second support conductor, shielding copper wire, first support conductor and sensing unit on the inner lining insulation layer. Combined with the stranding step, a shielding gap is obtained. After forming a copper wire shielding structure layer, a semiconducting resistive water tape is obtained through a wrapping process.

[0014] The present invention has the following beneficial effects:

[0015] 1. This invention optimizes the copper wire shielding structure based on the conventional sensor cable structure and is mainly applied to medium and high voltage cables. Essentially, it uses multiple copper wires as a shielding layer to support and protect the sensing unit. Firstly, two large-diameter second support conductors provide initial support and protection for the sensing unit, preventing stress from compressive deformation from directly affecting it. Secondly, shielding copper wires and a first support conductor are added to the second support conductors, further limiting their diameter difference and arrangement. This allows the multiple shielding copper wires and the first support conductor to form a continuous triangular structure, primarily dispersing the stress from compressive deformation in both directions, further reducing the stress's impact on the sensing unit.

[0016] 2. To reiterate the above, the first supporting conductor is located on the outer side of the cable, while the shielding copper wire is located on the inner side. Therefore, when the sensor cable is under pressure deformation / bending, each copper wire squeezes against each other, causing the shielding copper wire to tend to move inward and the first supporting conductor to tend to move outward. To further optimize the forming process, the arrangement of the shielding copper wire, the first supporting conductor, the second supporting conductor, and the sensing unit is restricted by the cable sleeve. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the copper wire shielded single-core sensing cable proposed in this invention.

[0019] Figure 2 This is a schematic diagram showing the location of the forming process of the copper wire shielded single-core sensor cable proposed in this invention.

[0020] Figure 3 This is a cross-sectional view of the copper wire shielded single-core sensing cable proposed in this invention.

[0021] Figure 4 This is a schematic diagram of the splitter assembly in the molding process of the copper wire shielded single-core sensor cable proposed in this invention.

[0022] Figure 5 In the molding process of the copper wire shielded single-core sensing cable proposed in this invention Figure 4 A partial sectional view;

[0023] Figure 6 In the molding process of the copper wire shielded single-core sensing cable proposed in this invention Figure 2 A sectional view;

[0024] Figure 7 This is a front view of the cable sleeve in the forming process of the copper wire shielded single-core sensor cable proposed in this invention;

[0025] Figure 8 This is a schematic diagram of the structure of the first card in the molding process of the copper wire shielded single-core sensor cable proposed in this invention.

[0026] Figure 9 This is a schematic diagram of the second card in the molding process of the copper wire shielded single-core sensor cable proposed in this invention.

[0027] In the diagram: 1. Semiconductor resistive water strip; 2. Copper wire shielding structure layer; 201. Shielding gap; 202. Shielding copper wire; 203. First supporting conductor; 204. Second supporting conductor; 3. Inner insulating layer; 4. Copper conductor assembly; 5. Connecting sleeve assembly; 6. Cable tray; 601. First cable tray; 602. Second cable tray; 7. Metal protective tube; 8. Grating optical fiber; 901. First card; 902. Second card; 903. Corrugated strip; 904. Wire guide wheel. Detailed Implementation

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1: For single-core sensing cables, because the key internal optical fiber is a flexible material, it is subject to pressure during cable manufacturing, laying, and operation, causing localized deformation. This directly affects the sensing performance of the optical fiber, and may even lead to loss of sensing capability due to fiber breakage. The following technical solution is proposed to address this issue:

[0030] Reference Figures 1-9 The copper wire shielded single-core sensing cable in this embodiment is based on cable shielding armor processing. The single-core sensing cable includes a copper conductor assembly 4, an inner insulation layer 3, and a semi-conductive resistive water tape 1. The feature is that a copper wire shielding structure layer 2 is provided between the semi-conductive resistive water tape 1 and the inner insulation layer 3. The copper wire shielding structure layer 2 includes a shielding gap 201, a second support conductor 204, a shielding copper wire 202, and a first support conductor 203. One or more sensing units are provided in the copper wire shielding structure layer 2.

[0031] The sensing unit consists of a metal protective tube 7 and a grating optical fiber 8. The second support conductor 204, the shielding copper wire 202 and the first support conductor 203 are arranged along the length of the copper conductor assembly 4, and the second support conductor 204 is located on both sides of the sensing unit. The shielding copper wire 202 and the first support conductor 203 are arranged in a ring array along the center point of the copper conductor assembly 4.

[0032] The diameters of the second support conductor 204 and the first support conductor 203 are larger than the outer diameter of the metal protective tube 7. The diameter of the shielding copper wire 202 is smaller than the diameters of the second support conductor 204, the first support conductor 203, and the metal protective tube 7. The inner insulating layer 3 is located in the middle of the copper conductor assembly 4 and the copper wire shielding structure layer 2. The semiconducting resistive water tape 1 is located at the outermost layer of the single-core sensing cable. The gap between the second support conductor 204, the shielding copper wire 202, and the first support conductor 203 forms a shielding gap 201. The shielding copper wire 202 is located on both sides of the first support conductor 203, and the distance between the center point of the shielding copper wire 202 and the center point of the copper conductor assembly 4 is smaller than the distance between the center point of the first support conductor 203 and the center point of the copper conductor assembly 4. The second support conductor 204 is tangent to the metal protective tube 7 in the sensing unit.

[0033] Furthermore, the distance between the center point of the first supporting conductor 203 and the center point of the copper conductor assembly 4 is greater than the distance between the center point of the second supporting conductor 204 and the center point of the copper conductor assembly 4.

[0034] Solution Description: The structure of a conventional single-core sensing cable is basically similar to that of a cable, except that a sensing unit is added. Specifically, it is based on grating optical fiber 8 and is mainly used in medium and high voltage cables. Regarding the sensing unit in this invention, the number of units is not specifically limited, one or more. Thus, one sensing unit can be used as a temperature sensing module, and another sensing unit can be used as a vibration measurement module. This part will not be explained in detail. However, the optical fiber material is relatively soft, while the overall mass of the cable is relatively large, which may cause the optical fiber to bend or even break. The conductor part of the single-core optical fiber sensing cable also includes a conductor semi-conductive shielding layer, an insulation layer, and an insulating semi-conductive shielding layer set outside the copper conductor assembly 4. The optical fiber sensing unit 5 is composed of a metal protective tube, grating optical fiber, and possibly thixotropic water-blocking filler.

[0035] Specifically, this invention uses a copper wire shielding structure layer 2 to protect the sensing unit, and the following related descriptions are provided:

[0036] S1: The key lies in the arrangement of the second support conductor 204, so as to... Figure 3 For example, the second support conductor 204 is located on both sides of the sensing unit. It is also necessary to ensure that the outer diameter of the second support conductor 204 is larger than the outer diameter of the sensing unit, and that there is no gap between the second support conductor 204 and the sensing unit. Essentially, this is to ensure that the second support conductor 204 and the sensing unit are tangent, and to further limit the distance between the two and the center point of the copper conductor assembly 4, so that the sensing unit is always located in the middle position of the two second support conductors 204 and is protected. When the cable is locally compressed, the structure that bears the stress first is the support copper wire 204 rather than the sensing unit.

[0037] S2: Because the extent of cable deformation under pressure is difficult to determine, a shielding copper wire 202 and a first supporting conductor 203 are added again around the location where the supporting copper wire 204 is installed, so as to... Figure 3 For example, since there are two sensing units in the figure, shielding copper wires 202 and first support conductors 203 need to be arranged in sequence around the middle position of these two sets of sensing units. It can be indirectly understood that the shielding copper wires 202, the second support conductors 204, and the first support conductors 203 are tangent to each other. However, it should be noted that there are no contact points between the shielding copper wires 202, because the shielding copper wires 202 mainly serve a shielding function and are arranged according to process parameters. Therefore, the first support conductors 203 need to be set again between the shielding copper wires 202. The function of the first support conductors 203 is to provide additional support for the shielding copper wires 202. Essentially, they can be made of metal materials such as aluminum wire. Thus, it can be understood that a full-arc protection structure is formed by the shielding copper wires 202, the first support conductors 203, the second support conductors 204, and the sensing units. Furthermore, a semi-conductive resistive water tape 1 is generated through a stranding process to maintain the roundness of the cable.

[0038] S3: The number of shielding copper wires 202 and the first supporting conductor 203 needs to be determined in accordance with the short-circuit current of the copper conductor assembly 4. Essentially, the short-circuit current of the copper conductor assembly 4 needs to be "averaged" through the shielding copper wires 202. Therefore, the number of shielding copper wires 202 is limited by the cross-sectional area of ​​the copper conductor assembly 4. Referring again to the arrangement of shielding copper wires 202 and the first supporting conductor 203, it is necessary to ensure that there is contact between the two but no contact between the shielding copper wires 202. Based on the short-circuit current, the number of shielding copper wires 202 and the cross-sectional area can be calculated. There is no relevant standard for the specific calculation method, which is only related to the application environment and is not limited in this invention.

[0039] Example 2: Supplementary explanation of the copper wire shielding structure layer in Example 1:

[0040] Combined again Figure 3Referring to the stress changes during the bending of a cylinder, the large bending area of ​​the cylinder is under tension, while the small bending area is under compression. This further limits the difference in diameter and position between the shielding copper wire 202 and the first supporting conductor 203. It can be understood that the shielding copper wire 202 is closer to the inner insulating layer 3, while the first supporting conductor 203 is relatively farther away from the inner insulating layer 3. Furthermore, plastic material is injected into the entire shielding copper wire 202, the first supporting conductor 203, the second supporting conductor 204, and the sensing unit to form a shielding gap 201, thereby protecting one shielding copper wire in an adjacent position. The shielding copper wire 202 and the two first support conductors 203 form a triangular structure, which in turn forms a continuous triangular structure. Therefore, when the sensing cable is subjected to pressure and bending, the shielding copper wire 202 tends to move closer to the inner insulation layer 3, while the first support conductors 203 tend to move further away from the inner insulation layer 3. The purpose is to disperse the stress generated by the cable and let it be borne by the semiconducting resistance water strip 1 and the inner insulation layer 3. Specifically, it reduces the stress burden on the sensing unit. For this purpose, the semiconducting resistance water strip 1 and the inner insulation layer 3 can also be reinforced with metal materials to improve the structural strength.

[0041] Example 3: Based on the technical content of Example 1, the molding process of the integral single-core sensing cable is further explained:

[0042] The forming process includes raw material preparation, stranding and forming, copper wire cabling, and wrapping of semiconducting resistive water tape. The raw material preparation step yields metal shielding wire, optical fiber sensing unit, and semiconducting resistive water tape. In the stranding and forming step, the sensing unit is arranged with the second support conductor 204, shielding copper wire 202, and first support conductor 203, and stranded to obtain a shielded sensing structure layer. In the copper wire cabling reinforcement step, a splitter kit is used to lay the second support conductor 204, shielding copper wire 202, first support conductor 203, and sensing unit on the inner insulating layer 3. Combined with the stranding and forming step, a shielding gap 201 is obtained, forming a copper wire shielding structure layer 2. The semiconducting resistive water tape 1 is then obtained through the wrapping process.

[0043] The splitter assembly consists of a connecting sleeve assembly 5 and a cable tray 6. During the stranding and sheathing processes, the conduction direction of the single-core sensing cable is along the direction from the cable tray 6 to the connecting sleeve assembly 5.

[0044] The inner wall of the cable sleeve 6 is provided with a first groove 601 corresponding to the shielding copper wire 202 and a second groove 602 corresponding to the first support conductor 203 and the second support conductor 204. A second card 902 is provided in the first groove 601, and a first card 901 is provided in the second groove 602 corresponding to the sensing unit. A corrugated strip 903 is provided on the outer wall of the first card 901 near the copper conductor assembly 4. The corrugated strip 903 is tangent to the outer surface of the shielding copper wire 202. Multiple guide wheels 904 are rotatably mounted on the outer wall of the second card 902 corresponding to the copper conductor assembly 4. The guide wheels 904 are provided with grooves corresponding to the insulating heat-conducting layer 203.

[0045] Operating Principle: First, the conventional cable manufacturing process will be explained: Essentially, it utilizes an automated shielding armoring machine. The three main steps—raw material preparation, stranding, and sheath processing—will not be discussed in detail. What needs to be explained is the copper wire reinforcement step for the copper wire shielding structure layer 2. More specifically, in conjunction with the relevant content described in Example 2, it is necessary to restrict the placement of the shielding copper wire 202, the first supporting conductor 203, the second supporting conductor 204, and the sensing unit. Therefore, a cable sleeve 6 is added. Specifically, this is combined with... Figures 5-9 Provide explanations and cooperation Figure 2 This can be understood as the entire single-core sensing cable continuously transmitting data from right to left. Since the shielding copper wire 202, the first supporting conductor 203, and the second supporting conductor 204 are key components that enhance the cable structure, the configuration of these three components needs to be limited according to the technical content of Embodiment 2. In this regard, the cable conduit 6 is used as the key structure, and the following explanation is provided:

[0046] The main function of the cable sleeve 6 is to limit the shielding copper wire 202, the first support conductor 203, and the second support conductor 204, so as to... Figure 7 Specifically, the triangular structure is formed by restricting the setting position of the shielding copper wire 202 and the first support conductor 203. It is necessary to ensure that the cable sleeve 6 is located in the subsequent structure of the connecting sleeve assembly 5, mainly to maintain the position of the shielding copper wire 202, the first support conductor 203 and the second support conductor 204.

[0047] It should also be noted that the first card 901 and the second card 902 are needed to further restrict the placement of the shielding copper wire 202 and the sensing unit to ensure that they are in full contact with the inner lining structure layer 3. For this purpose, the first card 901 needs to be in full contact with the shielding copper wire 202, but it should not interfere excessively with the shielding copper wire 202 in conjunction with the cable transmission process. Therefore, the corrugated strip 903 is needed to contact the shielding copper wire 202 and can move slightly in conjunction with the transmission process of the shielding copper wire 202, but it is necessary to ensure that the shielding copper wire 202 entering the connecting sleeve assembly 5 is in a fully taut state, while the first support conductor 203 does not need to interfere too much.

[0048] As a key structure within a single-core sensing cable, the sensing unit requires a guide wheel 904 to ensure its transmission process and to ensure that it makes full contact with the inner insulation layer 3. When the optical fiber is used as a temperature sensing element, it is more conducive to quickly acquiring the temperature changes of the conductor.

[0049] In summary, a protective structure is proposed for the sensing unit in a single-core sensing cable. Essentially, a second support conductor with a slightly larger diameter is placed on both sides of the sensing unit. The remaining perimeter is based on multiple interlaced copper wires of varying diameters, arranged with gaps along the outer edge of the conductor insulation layer, maintaining a compact arrangement between the second support conductor and the sensing unit. The purpose is to support and protect the sensing unit, preventing deformation under pressure during installation and operation from affecting the sensing effect, and maintaining the overall roundness of the cable as much as possible. Semiconductor resistive water tape is used to block water at the gaps. Combined with the sensing unit and the second support conductors on both sides, it withstands external radial pressure, preventing direct pressure on the sensing unit. Furthermore, the overall forming process of the sensing cable is optimized and improved to maintain the wiring arrangement of the shielding copper wire, the first support conductor, the second support conductor, and the sensing unit during the forming process.

[0050] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

[0051] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0052] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A copper wire shielded single-core sensing cable, wherein the single-core sensing cable is machined based on cable shielding armor, and the single-core sensing cable includes a copper conductor assembly (4), an inner insulation layer (3), and a semi-conductive resistive water tape (1), characterized in that, A copper wire shielding structure layer (2) is provided between the semiconducting resistive water strip (1) and the inner lining insulation layer (3). The copper wire shielding structure layer (2) includes a shielding gap (201), a second supporting conductor (204), a shielding copper wire (202) and a first supporting conductor (203). One or more sensing units are provided in the copper wire shielding structure layer (2). The sensing unit is composed of a metal protective tube (7) and a grating optical fiber (8). The second support conductor (204), the shielding copper wire (202) and the first support conductor (203) are arranged along the length of the copper conductor assembly (4), and the second support conductor (204) is located on both sides of the sensing unit. The shielding copper wire (202) and the first support conductor (203) are arranged in a ring array along the center point of the copper conductor assembly (4). The diameters of the second support conductor (204) and the first support conductor (203) are larger than the outer diameter of the metal protective tube (7), and the diameter of the shielding copper wire (202) is smaller than the diameters of the second support conductor (204), the first support conductor (203), and the metal protective tube (7).

2. The copper wire shielded single-core sensing cable according to claim 1, characterized in that, The inner insulating layer (3) is located in the middle of the copper conductor assembly (4) and the copper wire shielding structure layer (2), the semiconducting resistive water tape (1) is located in the outermost layer of the single-core sensing cable, and the gap between the second supporting conductor (204), the shielding copper wire (202) and the first supporting conductor (203) forms a shielding gap (201).

3. The copper wire shielded single-core sensing cable according to claim 1, characterized in that, The shielding copper wire (202) is located on both sides of the first support conductor (203), and the distance between the center point of the shielding copper wire (202) and the center point of the copper conductor assembly (4) is less than the distance between the center point of the first support conductor (203) and the center point of the copper conductor assembly (4). The second support conductor (204) is tangent to the metal protective tube (7) in the sensing unit. Furthermore, the distance between the center point of the first supporting conductor (203) and the center point of the copper conductor assembly (4) is greater than the distance between the center point of the second supporting conductor (204) and the center point of the copper conductor assembly (4).

4. The molding process of the copper wire shielded single-core sensing cable is applied in the production process of the copper wire shielded single-core sensing cable as described in any one of claims 1 to 3, characterized in that, The forming process includes raw material preparation, stranding and forming, copper wire wiring and semiconducting resistive water tape wrapping. The raw material preparation step yields metal shielding wire, optical fiber sensing unit and semiconducting resistive water tape. In the stranding and forming step, the sensing unit, the second support conductor (204), the shielding copper wire (202) and the first support conductor (203) are arranged as described in claims 3 and 4 and stranded to obtain a shielded sensing structure layer. In the copper wire reinforcement step, a splitter kit is used to lay a second support conductor (204), a shielded copper wire (202), a first support conductor (203), and a sensing unit on the inner lining insulation layer (3). In conjunction with the stranding and forming step, a shielding gap (201) is obtained, and a copper wire shielding structure layer (2) is formed. Then, a semiconducting resistive water tape (1) is obtained through a wrapping process.

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