Waterproof crosslinked polyethylene insulated power cable

Abstract

The invention relates to the technical field of power cables, and provides a waterproof cross-linked polyethylene insulated power cable, which comprises a plurality of conductors arranged in a stranded manner, a lining layer, a sheath structure, an expansion water-blocking structure and a protection structure, the outside of each conductor is coated with a cross-linked polyethylene insulating layer, the lining layer is arranged outside the plurality of conductors, and the sheath structure is arranged outside the plurality of conductors. A filling layer is arranged between the inside of the lining layer and the plurality of conductors, a sheath structure is arranged outside the lining layer, an expansion water-blocking structure is arranged inside the sheath structure, a protection structure is arranged outside the sheath structure, the sheath structure comprises an inner sheath layer and an outer sheath layer, the inner sheath layer is coated outside the lining layer, and the outer sheath layer is coated outside the outer sheath layer. According to the technical scheme, the power cable solves the problem that in the prior art, when the cable is laid in a humid or water-containing environment, if the sheath layer of the cable is damaged, water easily intrudes into the power cable, and normal use of the cable is affected.

Description

Technical Field

[0001] This invention relates to the field of power cable technology, specifically to a waterproof cross-linked polyethylene insulated power cable. Background Technology

[0002] A cable is an electrical energy or signal transmission device, typically composed of a conductor, an insulation layer, and a sheath. It has the characteristics of being internally energized and externally insulated. Cables are widely used in urban underground power grids, power plant lead-out lines, internal power supply in industrial and mining enterprises, and underwater power transmission lines across rivers and seas. These cables consist of single or multiple conductors and insulation layers, and are used to connect circuits and electrical appliances.

[0003] When cables are laid in humid or wet environments (such as mines or underwater operations), they are easily corroded by water, especially cross-linked polyethylene insulated power cables. Because cross-linked polyethylene materials are particularly sensitive to moisture, if water gets into the insulation during manufacturing and operation, "water treeing" can easily occur, greatly shortening the cable's service life. Therefore, cables in humid or wet environments need to have high water resistance to ensure normal use. Summary of the Invention

[0004] This invention proposes a waterproof cross-linked polyethylene insulated power cable to solve the problem in the prior art where, when the cable is laid in a humid or wet environment, if the cable sheath is damaged, moisture can easily penetrate the inside of the power cable, thus affecting the normal use of the cable.

[0005] The technical solution of the present invention is as follows: A waterproof cross-linked polyethylene insulated power cable includes multiple stranded conductors, each conductor being covered with a cross-linked polyethylene insulation layer, and further includes: An inner liner is disposed outside the plurality of conductors, and a filling layer is disposed between the inner liner and the plurality of conductors; A sheath structure is provided outside the inner liner layer to protect the power cable; An expansion water-blocking structure is provided inside the sheath structure to prevent fluid from entering the power cable by expansion. A protective structure is provided on the outside of the sheath structure to replace the sheath layer of the power cable and withstand external damage.

[0006] Based on the aforementioned scheme, the sheath structure includes an inner sheath layer and an outer sheath layer, with the inner sheath layer covering the outside of the inner lining layer and the outer sheath layer covering the outside of the inner sheath layer.

[0007] Based on the aforementioned solution, the expansion water-blocking structure includes: A water-stop layer is disposed between the inner sheath layer and the outer sheath layer, and the water-stop layer is formed by spirally winding several expansion water-stop strips; Each of the expansion sealing strips has an overlapping surface on both sides.

[0008] Based on the aforementioned scheme, it also includes wrapping tape, with a plurality of wrapping tapes spirally wound between the inner sheath layer and the outer sheath layer. The plurality of wrapping tapes correspond one-to-one with the plurality of expansion waterstop strips, and a wrapping tape is provided between every two expansion waterstop strips. The wrapping tape abuts against the overlapping surface of the expansion waterstop strip.

[0009] Based on the aforementioned solution, the protective structure includes: Positioning rings: A plurality of positioning rings are evenly spaced along the axial direction on the outer sheath layer; A fixing ring is coaxially fixedly installed between the inside of each positioning ring and the outer sheath layer; The outer sheath layer has several protective ropes arranged in a circumferential spiral on its exterior. The connecting part is installed on the protective rope, and the connecting part is used to fix the position of multiple protective ropes.

[0010] Based on the aforementioned solution, the connecting part includes: The positioning frame has several positioning frames arranged in a circumferential shape on the outside of each positioning ring, and the multiple positioning frames on the outside of each positioning ring are respectively installed on the corresponding protective rope; Each positioning ring has several snap-fit ​​slots on its outer side in an arc shape. Multiple positioning frames correspond one-to-one with multiple snap-fit ​​slots, and the snap-fit ​​slots are used to place the positioning frames.

[0011] Based on the aforementioned scheme, an annular groove is also included. Each positioning ring has an annular groove coaxially formed on its outer side, and a binding ring is provided inside each annular groove. The inner side of the binding ring abuts against the positioning frame.

[0012] The working principle and beneficial effects of this invention are as follows: 1. In this invention, when the outer sheath of a power cable is damaged and moisture enters the power cable through the damaged area, the expansion water-stop strip will first come into contact with the moisture. When water enters a damaged area of ​​the outer sheath, the moisture will come into contact with and wet the nearest expansion water-stop strip at the location closest to the damaged area of ​​the outer sheath. After absorbing water, the expansion water-stop strip will begin to expand radially, thereby sealing the damaged area of ​​the outer sheath, playing a waterproof role, and protecting the power cable.

[0013] 2. In this invention, when stones or ores fall and damage the outer sheath, if a stone hits the positioning ring, the fixed ring can absorb the impact force on the positioning ring, thereby reducing the impact force on the power cable. When a stone hits the protective rope, the protective rope can play a certain buffering role and change the direction of the stone's fall to a certain extent, so as to reduce the occurrence of heavy objects such as stones damaging the outer sheath of the power cable, thereby avoiding damage to the outer sheath and preventing external moisture from entering the power cable, which would affect the service life of the power cable.

[0014] 3. In this invention, through the cooperation of the sheath structure and the expansion water-blocking structure, when the outer sheath layer is damaged, external moisture will enter the power cable through the damaged location of the outer sheath layer. At this time, through the cooperation of the expansion water-blocking structure, the fluid intrusion is prevented by the expansion of the expansion water-blocking structure, thereby achieving a waterproof effect. By setting up the protective structure, the possibility of the outer sheath layer being damaged by external forces is reduced, thereby further enhancing the waterproofness of the power cable and the overall stability of the power cable. Attached Figure Description

[0015] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0016] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the combination of the sheath structure, the expansion water-blocking structure, and the protective structure in this invention. Figure 3 This is a schematic diagram of the combination of the sheath structure and the expansion water-blocking structure in this invention; Figure 4 This is a schematic diagram of the expansion water-blocking structure in this invention; Figure 5 This is a schematic diagram of the protective structure in this invention; Figure 6 This is a schematic diagram of the separated structure in cross-section of the protective structure in this invention.

[0017] In the diagram: 1. Conductor; 2. Cross-linked polyethylene insulation layer; 3. Inner lining layer; 4. Filler layer; 5. Inner sheath layer; 6. Outer sheath layer; 7. Expansion sealing strip; 8. Overlap surface; 9. Wrapping tape; 10. Positioning ring; 11. Fixing ring; 12. Protective rope; 13. Positioning frame; 14. Clip groove; 15. Annular groove; 16. Binding ring. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] like Figures 1 to 6 As shown in the figure, this embodiment proposes a waterproof cross-linked polyethylene insulated power cable, including multiple stranded conductors 1, each conductor 1 is covered with a cross-linked polyethylene insulation layer 2, and also includes an inner liner 3, a sheath structure, an expansion water-blocking structure, and a protective structure. The inner liner 3 is disposed outside the multiple conductors 1, and a filling layer 4 is disposed between the inner liner 3 and several conductors 1. The sheath structure is disposed outside the inner liner 3 to protect the power cable. The sheath structure includes an inner sheath layer 5 and an outer sheath layer 6. The inner sheath layer 5 is disposed outside the inner liner 3, and the outer sheath layer 6 is disposed outside the inner sheath layer 5.

[0020] Specifically, after the power cable is laid, the protective structure can effectively prevent damage to the outer sheath layer 6 from external forces. For example, it can prevent friction between the ground and other structures on the outer sheath layer 6 during cable laying, so that such damage is directed to the protective structure, thereby protecting the outer sheath layer 6 of the power cable.

[0021] In certain specific operating environments, such as mine environments, unexpected mechanical accidents may occur, such as roof collapse, mine car derailment, and pillar collapse. These accidents may cause ore to fall, thereby damaging the cable and the outer sheath 6 of the power cable. This allows external moisture to penetrate the power cable. By setting up a protective structure, external impacts or crushing damage can be blocked, thereby reducing the impact on the outer sheath 6 of the power cable, protecting the cable, and reducing the possibility of external moisture penetrating the outer sheath 6.

[0022] When the outer sheath layer 6 is damaged, the expansion water-blocking structure will come into contact with the outside. When external moisture enters the power cable through the damaged location of the outer sheath layer, the expansion water-blocking structure will expand. In the presence of fluid, the expanded water-blocking structure tightly seals the damaged location of the outer sheath layer 6, thereby preventing moisture from entering the power cable.

[0023] like Figure 3 , Figure 4 As shown, the sheath structure has an expansion water-blocking structure inside, which is used to prevent fluid from entering the power cable by expansion. The expansion water-blocking structure includes a water-stopping layer, which is set between the inner sheath layer 5 and the outer sheath layer 6. The water-stopping layer is made of several expansion water-stopping strips 7 spirally wound. Each expansion water-stopping strip 7 has an overlapping surface 8 on both sides. It also includes wrapping tape 9. Several wrapping tapes 9 are spirally wound between the inner sheath layer 5 and the outer sheath layer 6. Several wrapping tapes 9 correspond one-to-one with several expansion water-stopping strips 7. There is a wrapping tape 9 between every two expansion water-stopping strips 7. The wrapping tape 9 abuts against the overlapping surface 8 of the expansion water-stopping strip 7.

[0024] Among them, the expansion sealing strip 7 is a strip-shaped sealing material with water-swelling properties, which is made of more than ten kinds of materials through intensive mixing and extrusion. It has the characteristics of high expansion ratio and strong mobility and replenishment.

[0025] Specifically, when the outer sheath 6 of the power cable is damaged, and moisture enters the power cable through the damaged area, the expansion sealing strip 7 will first come into contact with the moisture. When water enters through a damaged area of ​​the outer sheath 6, the moisture will contact and wet the nearest expansion sealing strip 7 at the location closest to the damaged area. Once the expansion sealing strip 7 absorbs water, it begins to expand radially. Due to the overlapping surface 8, a wrapping tape 9 is also provided on the outside of the expansion sealing strip 7. The wrapping tape 9 has a certain degree of elasticity, thus restricting the expansion force of the expansion sealing strip 7, preventing it from being completely released outwards, and instead directing it towards... The inner sheath layer 5 is oriented in a concentrated manner. At this time, the expansion water-stop strip 7 will actively press the inner sheath layer 5, thereby preventing the longitudinal diffusion of water. At the same time, due to the spiral arrangement of several expansion water-stop strips 7, the force generated by the expansion water-stop strip 7 during expansion will also be transmitted to the adjacent expansion water-stop strips 7. Thus, when there is a certain water pressure in the outside (such as in an underwater environment), the water-blocking layer in this area can be kept in a compressed state, thereby resisting the action of external water pressure and preventing water from entering the inside of the power cable. At the same time, due to the expansion of the expansion water-stop strip 7, the damaged position of the outer sheath layer 6 is sealed, thereby playing a waterproof role.

[0026] like Figure 5 , Figure 6As shown, a protective structure is provided on the outside of the sheath structure to replace the sheath layer of the power cable and withstand external damage. The protective structure includes positioning rings 10, fixing rings 11, protective ropes 12, and connecting parts. Several positioning rings 10 are evenly arranged on the outer sheath layer 6 along the axial direction. Each positioning ring 10 is coaxially fixed with a fixing ring 11 inside and outside the outer sheath layer 6. Several protective ropes 12 are arranged in a circumferential spiral on the outside of the outer sheath layer 6. The protective ropes 12 have good strength and wear resistance. Connecting parts are installed on the protective ropes 12 to fix the positions of multiple protective ropes 12.

[0027] Specifically, the fixing ring 11 is installed while the cable is being laid, and then the positioning ring 10 is installed on the fixing ring 11. Then, the protective rope 12 is fixed on the positioning ring 10 closest to the end of the power cable. The protective rope 12 is wrapped around multiple positioning rings 10 at a certain angle, and the relative position of the protective rope 12 and the positioning ring 10 is fixed by setting the connecting part, thus completing the installation.

[0028] When the cable is in a special environment where stones or ores fall and damage the outer sheath 6, if a stone hits the positioning ring 10, the fixed ring 11 can absorb the impact force on the positioning ring 10, thereby reducing the impact force on the power cable. When a stone hits the protective rope 12, the protective rope 12 can play a certain buffering role and change the direction of the stone's fall to a certain extent, so as to reduce the occurrence of heavy objects such as stones damaging the outer sheath 6 of the power cable, thereby reducing the occurrence of damage to the outer sheath 6.

[0029] The above, such as Figure 5 , Figure 6 As shown, the connecting part includes a positioning frame 13 and a snap-fit ​​groove 14. Each positioning ring 10 has several positioning frames 13 arranged in a circumferential shape on its outer side. The multiple positioning frames 13 on the outer side of each positioning ring 10 are respectively installed on the corresponding protective rope 12. Each positioning ring 10 has several snap-fit ​​grooves 14 arranged in an arc shape on its outer side. The multiple positioning frames 13 correspond one-to-one with the multiple snap-fit ​​grooves 14. The snap-fit ​​grooves 14 are used to place the positioning frames 13.

[0030] Specifically, when it is necessary to fix the relative position of the protective rope 12 and the positioning ring 10, first install the positioning frame 13 on the protective rope 12, then snap the positioning frame 13 into the corresponding snap-fit ​​groove 14 on the outside of the positioning ring 10, and then repeat this step to fix multiple protective ropes 12 on the positioning ring 10 respectively, and then fix the position of the positioning frame 13 and the snap-fit ​​groove 14.

[0031] The above, such as Figure 5 , Figure 6As shown, it also includes an annular groove 15. Each positioning ring 10 has an annular groove 15 coaxially formed on its outer side. Each annular groove 15 has a binding ring 16 inside it. The inner side of the binding ring 16 abuts against the positioning frame 13.

[0032] Specifically, when fixing the positions of the positioning frame 13 and the snap-fit ​​groove 14, the groove on the outside of the positioning frame 13 is aligned with the annular groove 15, and then the binding ring 16 is fixed in the annular groove 15 outside the positioning ring 10. At this time, the inner side of the binding ring 16 is located in the groove of the positioning frame 13, thereby fixing the relative positions of the positioning frame 13 and the snap-fit ​​groove 14.

[0033] The working principle or usage process of this application is as follows: After the power cable is laid, the positioning ring 10 and the protective rope 12 can effectively prevent damage to the outer sheath layer 6 from external forces. For example, in certain operating environments, such as mines, there may be unexpected mechanical accidents such as roof collapse, mine car derailment, and pillar collapse. These accidents may cause ore to fall, thereby damaging the cable and the outer sheath layer 6 of the power cable, allowing external moisture to penetrate the cable. With the help of the positioning ring 10 and the protective rope 12, if a stone hits the positioning ring 10, the fixing ring 11 can absorb the impact force on the positioning ring 10, thereby reducing the impact force on the power cable. When a stone hits the protective rope 12, the protective rope 12 can play a certain buffering role and change the direction of the stone's fall to a certain extent, thereby reducing the occurrence of heavy objects such as stones damaging the outer sheath layer 6 of the power cable, thus reducing the occurrence of damage to the outer sheath layer 6 and protecting the outer sheath layer 6 of the power cable.

[0034] When the outer sheath 6 of the power cable is damaged, and moisture enters the cable through the damaged area, the expansion sealing strip 7 will first come into contact with the moisture. When water enters through a damaged area of ​​the outer sheath 6, the moisture will contact and wet the nearest expansion sealing strip 7 at the location closest to the damaged area. Once the expansion sealing strip 7 absorbs water, it begins to expand radially. Due to the overlapping surface 8, a wrapping tape 9 is also provided on the outside of the expansion sealing strip 7. The wrapping tape 9 has a certain degree of elasticity, which restricts the expansion force of the expansion sealing strip 7, preventing it from being completely released outwards, and instead causing it to expand inwards. With the inner sheath 5 oriented in a concentrated direction, the expansion water-stop strip 7 will actively press the inner sheath 5, thereby preventing the longitudinal diffusion of water. At the same time, due to the spiral arrangement of several expansion water-stop strips 7, the force generated by the expansion water-stop strip 7 during expansion will also be transmitted to the adjacent expansion water-stop strips 7. Thus, when there is a certain water pressure in the outside (such as in an underwater environment), the water-blocking layer in this area can be kept in a compressed state, thereby resisting the action of external water pressure and preventing water from entering the inside of the power cable. At the same time, due to the expansion of the expansion water-stop strip 7, the damaged position of the outer sheath 6 is sealed, thereby playing a waterproof role.

[0035] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A waterproof cross-linked polyethylene insulated power cable, comprising multiple stranded conductors (1), each conductor (1) being covered with a cross-linked polyethylene insulation layer (2), characterized in that, Also includes: The inner liner (3) is disposed outside the plurality of conductors (1), and a filling layer (4) is disposed between the inner liner (3) and the plurality of conductors (1). The sheath structure is provided on the outside of the inner lining layer (3) to protect the power cable; An expansion water-blocking structure is provided inside the sheath structure to prevent fluid from entering the power cable by expansion. A protective structure is provided on the outside of the sheath structure to replace the sheath layer of the power cable and withstand external damage.

2. The waterproof cross-linked polyethylene insulated power cable according to claim 1, characterized in that, The sheath structure includes an inner sheath layer (5) and an outer sheath layer (6). The inner sheath layer (5) is provided on the outside of the inner lining layer (3), and the outer sheath layer (6) is provided on the outside of the inner sheath layer (5).

3. The waterproof cross-linked polyethylene insulated power cable according to claim 2, characterized in that, The expansion water-blocking structure includes: A water-stop layer is provided between the inner sheath layer (5) and the outer sheath layer (6), and the water-stop layer is formed by spirally winding several expansion water-stop strips (7); Each of the expansion sealing strips (7) has an overlapping surface (8) on both sides.

4. The waterproof cross-linked polyethylene insulated power cable according to claim 3, characterized in that, It also includes wrapping tape (9), with a plurality of wrapping tapes (9) spirally wound between the inner sheath layer (5) and the outer sheath layer (6). The plurality of wrapping tapes (9) correspond one-to-one with the plurality of expansion waterstop strips (7). A wrapping tape (9) is provided between every two expansion waterstop strips (7), and the wrapping tape (9) abuts against the overlapping surface (8) of the expansion waterstop strip (7).

5. A waterproof cross-linked polyethylene insulated power cable according to claim 4, characterized in that, The protective structure includes: Positioning rings (10), a plurality of positioning rings are provided at equal intervals along the axial direction on the outer sheath layer (6); Fixing ring (11): Each positioning ring (10) is coaxially fixedly installed with the fixing ring (11) between its interior and the outer sheath layer (6). Protective rope (12), the outer sheath layer (6) has several protective ropes (12) arranged in a circumferential spiral on the outside. The connecting part is installed on the protective rope (12) and is used to fix the position of multiple protective ropes (12).

6. A waterproof cross-linked polyethylene insulated power cable according to claim 5, characterized in that, The connecting part includes: Positioning frame (13), each of the positioning rings (10) has a plurality of positioning frames (13) arranged in a circumferential shape on the outside of each positioning ring (10), and the plurality of positioning frames (13) on the outside of each positioning ring (10) are respectively installed on the corresponding protective rope (12); The locking slots (14) are provided in an arc shape on the outside of each positioning ring (10). The multiple positioning frames (13) correspond one-to-one with the multiple locking slots (14). The locking slots (14) are used to place the positioning frames (13).

7. A waterproof cross-linked polyethylene insulated power cable according to claim 6, characterized in that, It also includes an annular groove (15), and each of the positioning rings (10) is coaxially provided with the annular groove (15) on its outside. Each of the annular grooves (15) is provided with a binding ring (16) inside, and the inner side of the binding ring (16) abuts against the positioning frame (13).

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