Power cable capable of reducing cable sheath cracking and installation equipment

Abstract

The invention relates to the technical field of cables, and particularly discloses a power cable capable of reducing cable sheath cracking and an installation device.The power cable capable of reducing cable sheath cracking comprises a winding piece, a cable core and an insulating layer wrapping the cable core, and the winding piece comprises a connecting rope; supporting pieces are fixed to the connecting rope at equal intervals, the connecting rope is spirally wound on the insulating layer, every two adjacent supporting pieces in the axis direction of the insulating layer are stacked in a staggered mode, the ends, away from the connecting rope, of the supporting pieces make contact with the insulating layer, and the winding piece is wrapped with an outer skin. According to the power cable capable of reducing cable sheath cracking, stress at the bending position of the power cable cannot be concentrated on one point of the sheath, the sheath is prevented from cracking due to excessive stretching, and stress concentration of the sheath is avoided in the process that the power cable is pulled to move by the mounting equipment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cables, in particular to a power cable and installation equipment for reducing cable sheath cracking. BACKGROUND

[0002] Cross-linked polyethylene insulated power cables are important links connecting power stations, substations and users, and bear the task of transmitting electric energy from the power generation end to the power consumption end. The cross-linked polyethylene insulated power cable comprises one or more conductor cores, an insulation layer and a protective outer sheath.

[0003] In the existing cable production process, the sheath is directly extruded by an extruder die outside the insulation layer in a molten state, and then cooled and shaped. The sheath and the insulation layer are tightly attached together to form a compact structure.

[0004] During the bending process of the cable, the outer side of the sheath at the bending position is elongated and the inner side of the sheath at the bending position is compressed because the sheath and the insulation layer are relatively fixed. The deformation stress generated by bending cannot be effectively dispersed or released, but is completely borne by the sheath itself. Under the repeated bending action, the bending position of the sheath is fatigued, eventually exceeds the elastic limit and appears micro-cracks. These cracks gradually expand with the increase of the number of bending, eventually forming a break. The break in the sheath causes water from the outside to enter the inside of the cable, the insulation performance of the cable is sharply reduced, there is a risk of electrical short circuit, and the service life of the cable is shortened, increasing the maintenance and replacement costs. SUMMARY

[0005] The technical problem to be solved by the present application is to overcome the existing defects and provide a power cable and installation equipment for reducing cable sheath cracking. The stress at the bending position of the present power cable is not concentrated on one point of the sheath, avoiding the sheath cracking due to excessive stretching. The present installation equipment avoids stress concentration of the sheath during the movement of pulling the power cable.

[0006] The technical solution adopted by the present application to solve the technical problem comprises: On the one hand, a power cable for reducing cable sheath cracking is provided, comprising a winding member, a core and an insulation layer wrapped outside the core. The winding member comprises a connecting rope, the connecting rope is fixed with support pieces at equal intervals, the connecting rope is spirally wound on the insulation layer, the two adjacent support pieces in the axial direction of the insulation layer are staggered and overlapped, and the end of the support piece away from the connecting rope is in contact with the insulation layer. The winding member is coated with a sheath.

[0007] The ratio of the area of the support piece to the area of the overlapping part of the two adjacent support pieces in the axial direction of the insulation layer is 2.0-5.0:1.0.

[0008] As a preferred technical solution of the present invention, a receiving cavity is formed between the outer skin and the insulating layer, and the receiving cavity is filled with a sealing liquid for repairing cracks in the outer skin.

[0009] As a preferred technical solution of the present invention, openings are provided on the several supporting sheets of the wrapping member.

[0010] As a preferred technical solution of the present invention, it also includes a long bag body spirally wound on the insulating layer, and the long bag body is fixedly connected to the connecting rope.

[0011] The long bag body has a folded state and an expanded state. The folded state of the long bag body has a first volume, and the expanded state of the long bag body has a second volume, and the second volume is greater than the first volume.

[0012] The long bag body is filled with gas, and the long bag body changes from a folded state to an expanded state.

[0013] As a preferred technical solution of the present invention, the plugging fluid is a sodium silicate solution or a borate flame retardant liquid.

[0014] As a preferred technical solution of the present invention, the length of the supporting piece in a direction perpendicular to the connecting rope is 2.0 cm-5.0 cm.

[0015] As a preferred technical solution of the present invention, the support sheet is an elastic metal sheet or an elastic plastic sheet, and the connecting rope is a carbon fiber rope, a steel wire rope or a plastic soft rope.

[0016] On the other hand, an installation device is also provided for use with any of the aforementioned power cables for reducing cable sheath cracking, comprising a base, a rotating ring mounted on the base, a plurality of blocking members provided at equal angles on the outer peripheral side of the ring, the base and one end of the elastic clip are fixedly connected, the other end of the elastic clip is close to the outer peripheral side of the ring, a plurality of rotating wheels are mounted at equal angles on the inner peripheral side of the ring, and the angle between the axis of the wheel and the axis of the ring is less than 90°.

[0017] The circular ring comprises a long arc segment, and a short arc segment that can be opened and closed is installed at the notch of the long arc segment.

[0018] The elastic clamping member and the blocking member cooperate to ensure that the ring can rotate only when the torque applied to the ring exceeds a set value.

[0019] As a preferred technical solution of the present invention, no less than two support rods are fixed on the base, or a hook is fixed on the base, and a positioning bolt is installed on the hook.

[0020] As a preferred technical solution of the present invention, supporting films are fixed to both ends of the base.

[0021] One end of the long arc segment is connected to the short arc segment via a rotating connector, and the other end of the long arc segment is detachably connected to the short arc segment via a limiting member.

[0022] Compared with the prior art, the present invention has the following beneficial effects: 1. The example of the present invention is a power cable that reduces the cracking of the cable sheath. On the one hand, when the power cable is subjected to external forces such as bending, stretching, and torsion, the staggered support sheets in the winding member can slide with each other. The stress at the bending position of the power cable will not be concentrated on one point of the sheath, but will be dispersed through the sliding of the staggered support sheets, thereby avoiding the sheath from cracking due to excessive stretching; on the other hand, when the sheath breaks due to cracking, the sealing liquid in the accommodating cavity flows through the break in the sheath to the outer peripheral side of the sheath, and the sealing liquid solidifies to seal the break in the sheath, thereby increasing the service life of the power cable and reducing maintenance costs; on the other hand, the long bag body in the accommodating cavity changes from a folded state to an expanded state, the hydraulic pressure of the sealing liquid in the accommodating cavity increases, and after a break appears on the sheath, the sealing liquid in the accommodating cavity flows out of the break. After multiple breaks appear in the sheath, the sealing liquid can seal multiple breaks, thereby improving the safety of the power cable and reducing the risk of accidents.

[0023] 2. The power cable with reduced cable sheath cracking according to the example of the present invention, when the power cable is subjected to impact, the wrapping member absorbs and buffers part of the impact, thereby reducing the risk of damage to the core and the insulation layer.

[0024] 3. In the installation device of the example of the present invention, when the power cable is pulled and moved, the power cable swings horizontally, and the height of the power cable at the ring changes continuously, thereby avoiding stress concentration on the outer skin. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of a partial cross-sectional structure of a power cable for reducing cable sheath cracking according to the present invention; Figure 2 for Figure 1 A magnified schematic diagram of the structure at A; Figure 3 for Figure 1 Schematic diagram of the winding structure; Figure 4 This is a schematic structural diagram of an embodiment of the installation device of the present invention; Figure 5 This is a schematic structural diagram of another embodiment of the installation device of the present invention; Figure 6 This is a structural schematic diagram of another embodiment of the installation equipment of the present invention.

[0026] In the figure: 1 outer skin, 2 support sheet, 3 connecting rope, 4 accommodating cavity, 5 opening, 6 wire core, 7 long bag body, 8 circular ring, 801 long circular arc segment, 802 blocking piece, 803 rotating connecting piece, 804 short circular arc segment, 805 limiting piece, 806 rotating wheel, 9 insulation layer, 10 base, 11 supporting rod, 12 bolt, 13 clamping hook, 14 bearing film, 15 elastic clamping piece. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0028] Embodiment one: Please refer to Figures 1-3 The embodiment discloses a power cable capable of reducing cracking of an outer skin, comprising a winding part, a wire core 6 and an insulation layer 9 wrapped outside the wire core 6. The winding part comprises a connecting rope 3, and elastic support sheets 2 are fixed on the connecting rope 3 at equal intervals. The connecting rope 3 is spirally wound on the insulation layer 9. Adjacent two support sheets 2 in the axial direction of the insulation layer 9 are staggered and overlapped. The end of the support sheet 2 away from the connecting rope 3 is in contact with the insulation layer 9. The winding part is coated with an outer skin 1.

[0029] The ratio of the area of the support sheet 2 to the area of the overlapping part of the adjacent two support sheets 2 in the axial direction of the insulation layer 9 is 2.0-5.0:1.0.

[0030] Further, the length of the support sheet 2 in the direction perpendicular to the connecting rope 3 is 2.0-5.0 cm.

[0031] Further, the connecting rope 3 is a carbon fiber rope, a steel wire rope or a plastic soft rope.

[0032] Further, the adjacent two support sheets 2 on the connecting rope 3 are staggered and overlapped.

[0033] The outer skin 1, the wire core 6 and the insulation layer 9 used in the present application are all common components of cables in the prior art, and their materials and production processes are all known technologies, which will not be described here.

[0034] The working process and principle of the embodiment are as follows: When the power cable is subjected to external forces such as bending, stretching and twisting, the staggered and overlapped support sheets 2 in the winding part can slide relative to each other. The stress at the bending position of the power cable is not concentrated on one point of the outer skin 1, but is dispersed through the sliding of the staggered and overlapped support sheets 2, thereby avoiding cracking of the outer skin 1 due to excessive stretching.

[0035] When the power cable is subjected to an impact, the wrapping member absorbs and buffers a portion of the impact, thereby reducing the risk of damage to the core 6 and the insulation layer 9.

[0036] The power cable is easy to bend, and the internal insulation layer 9 and the wire core 6 are protected from damage. Moreover, the staggered supporting sheets 2 can prevent the gnawing of rodents such as mice.

[0037] Example 2: like Figure 1 As shown, this embodiment discloses a power cable for reducing cable sheath cracking, and its structure is roughly the same as that of embodiment one, except that a receiving cavity 4 is formed between the sheath 1 and the insulating layer 9 of this embodiment, and the receiving cavity 4 is filled with a sealing liquid for repairing the sheath cracking.

[0038] The working process and principle of this embodiment are: When the outer sheath 1 is broken due to cracking, the sealing liquid in the accommodating cavity 4 flows to the outer peripheral side of the outer sheath 1 through the broken outer sheath 1, and the sealing liquid solidifies to seal the broken outer sheath 1, thereby increasing the service life of the power cable and reducing maintenance costs.

[0039] Preferably, the outer skin 1 is made of cross-linked polyethylene, and the insulating layer 9 is made of cross-linked polyethylene or polyethylene.

[0040] Furthermore, the step of injecting the plugging liquid into the accommodating cavity 4 of the power cable includes the following steps: This power cable is placed in a negative pressure container. A one-way valve is installed at one end of the power cable. The one-way valve allows the air in the accommodating chamber 4 to flow to the outside of the outer skin 1 through the one-way valve. The worker uses a vacuum pump to extract the air in the negative pressure container. When the gauge pressure in the negative pressure container is -0.093MPa to -0.098MPa, the worker uses a robotic arm or a delayed release structure to extend the end of the power cable away from the one-way valve into a container containing blocking liquid. Then the negative pressure container returns to an atmospheric pressure. The end of the power cable away from the one-way valve remains extended into the blocking liquid for 1h-24h, and the blocking liquid is absorbed into the accommodating chamber 4.

[0041] Furthermore, the support sheet 2 is an elastic metal sheet. Workers ground a portion of the support sheets 2 through a grounding wire to achieve electromagnetic shielding of the wire core 6. Preferably, the support sheet 2 is made of aluminum alloy or galvanized steel.

[0042] Furthermore, the plugging fluid is a sodium silicate solution or a borate flame retardant liquid.

[0043] Furthermore, polyol is added to the plugging fluid to reduce the minimum operating temperature of the power cable, and the polyol is ethylene glycol, propylene glycol or glycerin.

[0044] Example 3: likeFigure 1 and Figure 3 As shown in FIG. 3 and FIG. 4, the embodiment discloses a power cable with reduced cable sheath cracking, which has substantially the same structure as that of the second embodiment, except that the support sheet 2 of the winding member of the embodiment is provided with an opening 5.

[0045] The working process and principle of the embodiment are as follows: The opening 5 facilitates the flow of the sealing liquid inside and outside the support sheet 2.

[0046] Embodiment Four As shown in FIG. 5 and FIG. 6, the embodiment discloses a power cable with reduced cable sheath cracking, which has substantially the same structure as that of the third embodiment, except that the embodiment further comprises a long bag body 7 spirally wound on the insulation layer 9, and the long bag body 7 is fixedly connected with the connecting rope 3, and the diameter of the connecting rope 3 is greater than the thickness of the support sheet 2, and the connecting rope 3 provides a containing space for the long bag body 7. Figure 1 Figure 2 The long bag body 7 has a folded state and an expanded state, the folded state of the long bag body 7 has a first volume, and the expanded state of the long bag body 7 has a second volume, and the second volume is greater than the first volume.

[0047] The worker fills the long bag body 7 with gas, and the long bag body 7 changes from the folded state to the expanded state.

[0048] The working process and principle of the embodiment are as follows: The long bag body 7 is in the folded state during the process of inhaling the sealing liquid in the containing cavity 4.

[0049] When the containing cavity 4 is completely filled with the sealing liquid, and both ends of the power cable are sealed, one end of the long bag body 7 penetrates the sealing position and extends out of the sheath 1, the worker injects gas into the long bag body 7, the long bag body 7 in the containing cavity 4 changes from the folded state to the expanded state, the hydraulic pressure of the sealing liquid in the containing cavity 4 rises, the sealing liquid in the containing cavity 4 flows out of the broken part after the broken part appears on the sheath 1, and the sealing liquid can seal multiple broken parts after multiple broken parts appear on the sheath 1, thereby improving the safety of the power cable and reducing the risk of accidents.

[0050] Further, the gas is air, carbon dioxide, helium or nitrogen.

[0051] Embodiment Five As shown in FIG. 7 and FIG. 8, the embodiment discloses a power cable with reduced cable sheath cracking, which has substantially the same structure as that of the first embodiment, except that the support sheet 2 of the embodiment is an elastic plastic sheet.

[0052] The working process and principle of the embodiment are as follows: Figure 1 The long bag body 7 is in the folded state during the process of inhaling the sealing liquid in the containing cavity 4.

[0053] ​Furthermore, a shielding layer is provided between the wrapping member and the outer skin 1 to prevent electromagnetic interference.

[0054] Example 6: like Figures 4-6 As shown, this embodiment discloses an installation device, which is used in conjunction with any one of the power cables for reducing cable sheath cracking of embodiments one to five, and includes a base 10, on which a rotating ring 8 is mounted, and a plurality of blocking members 802 are provided at equal angles on the outer peripheral side of the ring 8. The base 10 is fixedly connected to one end of an elastic clip 15, and the other end of the elastic clip 15 is close to the outer peripheral side of the ring 8. A plurality of rotating wheels 806 are mounted at equal angles on the inner peripheral side of the ring 8, and the angle between the axis of the wheel 806 and the axis of the ring 8 is less than 90°, and the angle between the axis of the wheel 806 and the axis of the ring 8 is greater than or equal to 45°.

[0055] The circular ring 8 includes a long arc segment 801 , and an openable and closable short arc segment 804 is installed at the notch of the long arc segment 801 .

[0056] The elastic clamp 15 and the blocking member 802 cooperate to ensure that the ring 8 can rotate only when the torque applied to the ring 8 exceeds a set value.

[0057] The working process and principle of this embodiment are: In the power cable wiring process for reducing cable sheath cracking, the base 10 is located on a placement plane, the axis of the ring 8 is set horizontally, the power cable passes through the ring 8, and the sheath 1 of the power cable is pressed on the rotating wheel 806.

[0058] When the worker pulls the power cable to move, the elastic clip 15 abuts against the blocking member 802 to limit the rotation of the ring 8. The wheel 806 causes the power cable to swing horizontally, and the height of the power cable at the ring 8 increases. When the torque of the power cable on the ring 8 exceeds the set value, the elastic clip 15 and the blocking member 802 disengage, the power cable causes the ring 8 to rotate, the height of the power cable at the ring 8 decreases, and the elastic clip 15 abuts against another blocking member 802.

[0059] After the power cable is laid out, the short arc segment 804 on the long arc segment 801 is opened, and the power cable is detached from the long arc segment 801 .

[0060] During the process of pulling the power cable for wiring, the power cable swings horizontally to avoid stress concentration on the outer sheath 1 .

[0061] Furthermore, the direction of the friction force on the outer skin 1 is constantly changing, which reduces the relative sliding between the outer skin 1 and the insulating layer 9, thereby reducing the deformation of the outer skin 1.

[0062] Furthermore, the elastic clamp 15 is an elastic metal elastic sheet or an elastic plastic elastic sheet.

[0063] Furthermore, an arc-shaped slot is provided on the base 10 , and the ring 8 and the arc-shaped slot are slidably connected, so that the arc-shaped slot enables the ring 8 to rotate around the axis of the ring 8 .

[0064] Furthermore, the blocking member 802 is a slot provided on the outer side of the ring 8 or a protrusion fixed on the outer side of the ring 8, and an elastic pad is installed on the rotating wheel 806.

[0065] Embodiment seven: like Figure 4 As shown, this embodiment discloses an installation device, whose structure is roughly the same as that of Example 6, except that in this embodiment, no less than two support rods 11 are fixed on the base 10, and the support rods 11 are in contact with the supporting surface, thereby improving the stability of the position of the base 10 during the wiring of the power cable.

[0066] Embodiment 8: like Figure 5 As shown, this embodiment discloses a mounting device, the structure of which is substantially the same as that of the sixth embodiment, except that a hook 13 is fixed on the base 10 of this embodiment, and a positioning bolt 12 is installed on the hook 13 .

[0067] The working process and principle of this embodiment are: The worker clamps the hook 13 on the vertical side of the cable tray, and then rotates the bolt 12 so that the bolt 12 presses against the vertical side of the cable tray. The installation device is easy to lay out on the cable tray.

[0068] Embodiment 9: like Figures 4-6 As shown, this embodiment discloses a mounting device, the structure of which is substantially the same as that of the sixth embodiment, except that a long strip of soft carrying film 14 is fixed to both ends of the base 10 of this embodiment.

[0069] The carrier film 14 is located on the wiring path of the power cable to reduce the resistance to the movement of the power cable.

[0070] Preferably, the carrier film 14 is made of plant fiber fabric, synthetic fiber fabric or blended fabric.

[0071] Embodiment 10: like Figures 4-6 As shown, this embodiment discloses an installation device, whose structure is roughly the same as that of Example 6, except that, in this embodiment, one end of the long arc segment 801 and the short arc segment 804 are connected by a rotating connecting member 803, and the other end of the long arc segment 801 and the short arc segment 804 are detachably connected by a limiting member 805.

[0072] The working process and principle of the embodiment are as follows: The rotation connecting piece 803 enables the long circular arc segment 801 and the short circular arc segment 804 to rotate relative to each other.

[0073] Further, the rotation connecting piece 803 is a hinge, a hinged seat or an adhesive tape, and the limiting piece 805 is a magic tape, a bolt, a buckle or a quick release pin.

[0074] Although the embodiments of the present application have been shown and described, it is to be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application.

Claims

1. A power cable for reducing cable sheath cracking, comprising a core (6) and an insulating layer (9) wrapped around the core (6), characterized in that: The invention also includes a winding member, the winding member includes a connecting rope (3), support pieces (2) are fixed on the connecting rope (3) at equal intervals, the connecting rope (3) is spirally wound on the insulating layer (9), two adjacent support pieces (2) in the axial direction of the insulating layer (9) are staggered and stacked, and one end of the support piece (2) away from the connecting rope (3) is in contact with the insulating layer (9), and the winding member is covered with an outer skin (1); The ratio of the area of ​​the support sheet (2) to the area of ​​the overlapping portion of two adjacent support sheets (2) in the axial direction of the insulating layer (9) is 2.0-5.0:1.

0.

2. The power cable for reducing cable sheath cracking according to claim 1, characterized in that: A receiving cavity (4) is formed between the outer skin (1) and the insulating layer (9), and the receiving cavity (4) is filled with a plugging liquid for repairing cracks in the outer skin.

3. The power cable for reducing cable sheath cracking according to claim 2, characterized in that: Openings (5) are provided on the plurality of support sheets (2) of the wrapping member.

4. The power cable for reducing cable sheath cracking according to claim 3, characterized in that: It also includes a long bag body (7) spirally wound on the insulating layer (9), and the long bag body (7) is fixedly connected to the connecting rope (3); The long bag body (7) has a folded state and an expanded state. The folded state of the long bag body (7) has a first volume, and the expanded state of the long bag body (7) has a second volume, and the second volume is greater than the first volume. The long bag body (7) is filled with gas, and the long bag body (7) changes from a folded state to an expanded state.

5. The power cable for reducing cable sheath cracking according to claim 1, characterized in that: The plugging liquid is a sodium silicate solution or a borate flame retardant liquid.

6. The power cable for reducing cable sheath cracking according to claim 1, characterized in that: The length of the support sheet (2) in a direction perpendicular to the connecting rope (3) is 2.0 cm to 5.0 cm.

7. The power cable for reducing cable sheath cracking according to claim 1, characterized in that: The supporting sheet (2) is an elastic metal sheet or an elastic plastic sheet, and the connecting rope (3) is a carbon fiber rope, a steel wire rope or a plastic soft rope.

8. An installation device for use with the power cable for reducing cable sheath cracking according to any one of claims 1 to 7, characterized in that: The invention comprises a base (10), a rotating ring (8) is mounted on the base (10), a plurality of blocking members (802) are arranged at equal angles on the outer peripheral side surface of the ring (8), the base (10) is fixedly connected to one end of an elastic clamp (15), the other end of the elastic clamp (15) is close to the outer peripheral side surface of the ring (8), and a plurality of rotating wheels (806) are mounted at equal angles on the inner peripheral side surface of the ring (8), and the included angle between the axis of the wheel (806) and the axis of the ring (8) is less than 90°; The circular ring (8) comprises a long arc segment (801), and a short arc segment (804) that can be opened and closed is installed at the notch of the long arc segment (801); The elastic clamp (15) and the blocking member (802) cooperate to ensure that the ring (8) can only rotate when the torque applied to the ring (8) exceeds a set value.

9. The installation device according to claim 8, characterized in that: No less than two support rods (11) are fixed on the base (10), or a hook (13) is fixed on the base (10), and a positioning bolt (12) is installed on the hook (13).

10. The installation device according to claim 8, characterized in that: A supporting film (14) is fixed to both ends of the base (10); One end of the long arc segment (801) and the short arc segment (804) are connected via a rotating connector (803), and the other end of the long arc segment (801) and the short arc segment (804) are detachably connected via a limiting member (805).

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