A large-current flexible medium-voltage explosion-proof cable

Abstract

The application relates to the field of explosion-proof cables, and particularly discloses a large-current flexible medium-voltage explosion-proof cable, which comprises a long-rectangular-section row conductor, the row conductor is formed by horizontally stacking a plurality of wire row plates, wire grooves are linearly arranged on the wire row plates, and arc-shaped corner blocks are arranged on the two sides of the row conductor. The cable has long and short sides due to the long-rectangular design, the short side is shorter than the diameter of a cylindrical cable with the same specification, the cable has a smaller bending radius when being bent in the short side direction, and is more suitable for being laid in a narrow and multi-bending underground well or platform; the two sides of the row conductor are provided with arc-shaped corner blocks, the corner blocks are attached to the plurality of wire row plates, and the corner blocks form round corners on the edges and corners of the cable when surrounding the outer layer of the row conductor; the arc corners formed by the corner blocks can avoid sharp corners and play a role in preventing abrasion; and the corner blocks can share pressure and protect the wire row plates during pressure receiving.

Description

Technical Field

[0001] This invention relates to explosion-proof cable technology, specifically a high-current flexible medium-voltage explosion-proof cable. Background Technology

[0002] As is generally known, medium-voltage explosion-proof cables are cables that are avoided in explosive environments such as coal mines and chemical plants. The purpose is to minimize the risk of them becoming ignition sources due to electric arcs, sparks, or overheating, thereby protecting the environment in which they are used.

[0003] For example, the invention patent with application publication number CN120183799B, application publication date September 12, 2025, entitled "A Fireproof and Explosion-proof Cable," includes a conductor, an inner shielding layer, an insulation layer, an outer shielding layer, a filling layer, a wrapping layer, an armor layer, and an outer sheath. An isolation layer is fitted onto the outer wall of the wrapping layer, and a protective layer is fitted onto the outer wall of the isolation layer. Multiple sets of isolation layers and protective layers are provided and equidistantly distributed along the cable length. Through the protective layer, when a fire causes a significant increase in temperature around the outer sheath, the resulting high temperature is absorbed by the expanded graphite in the first expansion chamber. The expanded graphite causes the first expansion chamber to move the concave block towards the convex block, causing the vent holes and connecting holes to be alternately blocked, forming a heat-insulating protective layer. This prevents external high temperatures from entering the cable interior through the vent holes and connecting holes, preventing high temperatures from entering the conductor core, causing excessive heating, short circuits, or even explosions, thereby improving the cable's safety and service life.

[0004] The shortcoming of existing technology is that traditional explosion-proof cables, in order to prevent insulation damage caused by external forces such as crushing and impact in environments such as mines, are equipped with structures such as metal armor and outer sheaths to maintain explosion-proof capability. However, the flexibility of the circular cross-section core is affected after setting up several structures, and the minimum bending radius will increase, making it difficult to lay the cable in narrow, winding underground mines or platforms. Summary of the Invention

[0005] The purpose of this invention is to provide a high-current flexible medium-voltage explosion-proof cable to overcome the above-mentioned shortcomings in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-current flexible medium-voltage explosion-proof cable, comprising a rectangular conductor, wherein the conductor is formed by horizontally stacking several wire strips, and the wire strips are provided with wire grooves in a linear array. Arc-shaped corner blocks are provided on both sides of the conductor, and the corner blocks are attached to multiple wire strips to form rounded corners at the edges of the cable.

[0007] As a further description of the above technical solution: the conductor is provided with conductor shield, polypropylene shield, insulation shield, metal shield, inner wrapping layer, inner sheath, armor layer and outer sheath in sequence.

[0008] As a further description of the above technical solution: the outer sheath has deformation grooves arranged in a linear array in both horizontal directions.

[0009] As a further description of the above technical solution: the outer sheath is symmetrically provided with outer recessed grooves along the deformation groove, and a deformation wall serving as the inner wall of the deformation groove is provided between the two outer recessed grooves.

[0010] As a further description of the above technical solution: the armor layer includes metal wires spirally wound along the inner sheath.

[0011] As a further description of the above technical solution: the armor layer includes corner armor pieces arranged along the diagonal.

[0012] As a further description of the above technical solution: the inner wall of the corner armor plate is provided with an inlay groove corresponding to the metal wire.

[0013] As a further description of the above technical solution: the corner armor plate includes a vertical surface, and the vertical surface is provided with opposing horizontal steps.

[0014] As a further description of the above technical solution: the outer layer of the corner armor plate is provided with a restraining net, and the restraining net is embedded in the outer sheath.

[0015] As a further description of the above technical solution: the outer layer of the corner armor plate is provided with protrusions, and the restraint net includes a large hinge ring and a small hinge ring, with the large hinge ring hanging on the protrusions.

[0016] In the above technical solution, the high-current flexible medium-voltage explosion-proof cable provided by the present invention has the following beneficial effects: the cable has a long side and a short side due to its rectangular design. The short side has a shorter diameter than that of a cylindrical cable of the same specification, which makes the cable have a smaller bending radius when bending towards the short side, making it more suitable for laying in narrow, winding underground or platform areas. The two sides of the conductor are provided with arc-shaped corner blocks, which are attached to multiple cable trays. As they wrap around the outer layer of the conductor, they form rounded corners at the edges of the cable. The rounded corners formed by the corner blocks can avoid sharp corners and play a role in preventing wear. During the pressure process, the arc-shaped corner blocks share the pressure and protect the cable trays. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 This is a schematic diagram of the overall structure provided for an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the armor layer provided in an embodiment of the present invention; Figure 3 for Figure 2 Enlarged view of point A in the middle; Figure 4 This is a schematic cross-sectional view provided for an embodiment of the present invention; Figure 5 for Figure 4 Enlarged view of point B in the middle; Figure 6 This is a schematic diagram of the restraint mesh structure of the armor layer provided in an embodiment of the present invention; Figure 7 for Figure 6 Enlarged view of point C in the middle; Figure 8 This is a schematic diagram of the overall cross-sectional structure from another angle provided in an embodiment of the present invention; Figure 9 A schematic diagram of the metal wire winding at another helical angle for the armor layer provided in an embodiment of the present invention; Figure 10 This is a schematic diagram of another overall embodiment of the present invention. Figure 11 This is a schematic cross-sectional view of the outer sheath in a bent state provided in an embodiment of the present invention; Figure 12 This is a schematic diagram of another embodiment of the corner block provided in this invention; Figure 13 This is a schematic diagram of another overall embodiment of the present invention.

[0019] Explanation of reference numerals in the attached figures: 1. Outer sheath; 11. Deformation groove; 111. Deformation wall; 12. Outer recessed groove; 2. Armor layer; 20. Outer wrapping layer; 21. Metal wire; 22. Corner armor plate; 221. Raised point; 222. Horizontal step; 223. Inlay groove; 23. Binding net; 231. Large hinge ring; 232. Small hinge ring; 3. Inner sheath; 4. Inner wrapping layer; 5. Metal shield; 6. Insulating shield; 7. Polypropylene shield; 8. Conductor array; 81. Cable strip; 9. Corner block; 91. Adhesive surface; 92. Concave surface. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0021] Please see Figure 1-13 This invention provides a technical solution: a high-current flexible medium-voltage explosion-proof cable, such as... Figure 1 , Figure 8 and Figure 10 As shown, the cable includes a rectangular conductor 8, which is horizontally stacked from several wire strips 81. There are at least two wire strips 81, which are made of high-purity copper. Each wire strip 81 is plate-shaped and has multiple grooves arranged in a linear array on it, replacing densely packed copper wires. This ensures stable temperature and reliable performance during high-current transmission. The rectangular design of the cable provides both a long and a short side. The diameter of the short side is shorter than that of a cylindrical cable of the same specifications, resulting in a smaller bending radius when bent towards the short side (bending along the wider side). This makes it more suitable for laying in narrow, winding underground or platform environments. When bending along the long side (bending along the narrow side), special T-type, L-type and other adapters are used for conversion instead of direct bending. The bending ability of the long side is poor. The two sides of the conductor 8 are provided with arc-shaped corner blocks 9. The corner blocks 9 are attached to multiple cable trays 81. As they surround the outer layer of the conductor 8, they form rounded corners at the edges of the cable. Flat square cables naturally have anti-torsion and large transmission surface area, but the four corners are more prone to wear and deformation than round cables. The rounded corners formed by the corner blocks 9 can avoid sharp corners and play a role in preventing wear. During the pressure process, the arc-shaped corner blocks 9 share the pressure and protect the cable trays 81.

[0022] Furthermore, the corner block 9 has a mating surface 91 that fits into the conductor 8. The mating surface 91 can be changed to an arc shape or a vertical surface depending on the side of the conductor 8.

[0023] Furthermore, such as Figure 12 As shown, the arc apex of the corner block 9 has a concave surface 92, which forms a cavity. The cavity acts as a buffer to protect the conductor 8. The cavity does not contact the conductor 8 and will not affect the current conduction or heat conduction of the conductor 8.

[0024] Furthermore, such as Figure 1 As shown, the conductor 8 is provided with a conductor shielding layer, a polypropylene shielding layer 7, an insulating shielding layer 6, a metal shielding layer 5 (the metal shielding layer 5 is a copper strip shielding layer), an inner wrapping layer 4, an inner sheath 3 (the inner sheath 3 is made of polyvinyl chloride), an armor layer 2, and an outer sheath 1 in sequence. The armor layer 2 can be made of non-magnetic steel or aluminum alloy.

[0025] Furthermore, such as Figure 13As shown, the conductor 8 can also be a single wire strip plate 81. The wire strip plate 81 does not have wire grooves and is a smooth surface. The four diagonal sides of the wire strip plate 81 are rounded.

[0026] In another embodiment provided by the present invention, such as Figure 4 and Figure 5 As shown, the outer sheath 1 has deformation grooves 11 arranged in a linear array in two horizontal directions (the horizontal direction is the long side of the rectangular cross section). The deformation grooves 11 are composed of multiple connected arcs and are arranged through the long side of the rectangular cross section. They play a buffering role when hit by external objects. When bending along the short side is required, the deformation grooves 11 provide deformation space and increase the ability to bend in the short side direction.

[0027] Preferred, such as Figure 4 and Figure 5 As shown, the outer sheath 1 has symmetrically arranged outer recessed grooves 12 along the deformation groove 11. A deformation wall 111, serving as the inner wall of the deformation groove 11, is provided between the two outer recessed grooves 12. When bending the cable along the short side at a corner, the two outer recessed grooves 12 can be held in place with fingers, and while bending, the cable can be squeezed inwards (towards the conductor 8), causing the deformation wall 111 to be squeezed out, forming a protruding protrusion (such as...). Figure 11 As shown, the cable is raised in the bending direction and stretched in the other direction. The raised part is used to elevate the cable and increase the curvature when bending, thereby providing some protection for the internal conductor 8. When bending, one side of the horizontal surface will contract and the other side will stretch. When stretched, the deformation wall 111 moves closer to the deformation groove 11, and the two outer recessed grooves 12 compensate for the deformation wall 111 and relieve the tension on the surface of the outer sheath 1.

[0028] In another embodiment provided by the present invention, such as Figure 2 and Figure 9 As shown, the armor layer 2 includes a metal wire 21 spirally wound along the inner sheath 3. The metal wire 21 can be an aluminum alloy wire or a non-magnetic steel wire. The rotation angle of the metal wire 21 can be an obtuse angle, an acute angle, or a 45° angle. The larger the spiral winding angle of the metal wire 21, the less restrictive it is on the flexibility of the cable, but the strength will also decrease.

[0029] In another embodiment provided by the present invention, such as Figure 2 As shown, the armor layer 2 includes four corner armor pieces 22 arranged along the diagonal. These pieces are arranged at the diagonal to provide targeted protection for the corners and reduce the occurrence of half-side collapse due to pressure on one side.

[0030] Preferred, such as Figure 2 and Figure 3 As shown, the inner wall of the corner armor plate 22 is provided with an inlay groove 223 corresponding to the metal wire 21, which will make the corner armor plate 22 and the metal wire 21 fit more tightly.

[0031] When the cable is subjected to pressure on one side, the inner sheath 3 and the polypropylene shield 7 will deform, causing the corner armor plate 22 to move. At this time, the inlay groove 223 is fastened to the metal wire 21, and the metal wire 21 is spirally arranged. The moving inlay groove 223 fastens the spiral metal wire 21, thus distributing the pressure on one side.

[0032] Preferred, such as Figure 3 As shown, the corner armor plate 22 includes a vertical surface, and the vertical surface is provided with opposing horizontal steps 222. The outer sheath 1 fills the cavity between the two horizontal steps 222. The cavity between the horizontal steps 222 can deform and absorb vibration when under pressure, thus playing a protective role. The corner armor plate 22 is provided with an outer wrapping layer 20.

[0033] Preferred, such as Figure 6 As shown, a restraining net 23 is provided on the outer layer of the corner armor plate 22. The restraining net 23 is embedded in the outer sheath 1. The restraining net 23 is used to restrict the corner armor plate 22, binding the corner armor plate 22 so that it fits against the metal wire 21. The restraining net 23 is as follows: Figure 7 As shown, it is a diamond-shaped braid, which has a certain degree of freedom while also sharing the pressure. The outer sheath 1 is the outermost layer of the cable and is the part with the greatest degree of deformation. The binding net 23 is embedded in the outer sheath 1 when it is laid, serving as the base of the outer sheath 1 and limiting the maximum degree of deformation of the outer sheath 1 to prevent the outer sheath 1 from cracking due to excessive deformation.

[0034] Preferably, the outer layer of the corner armor plate 22 is provided with protrusions 221, such as... Figure 7 As shown, the restraint net 23 includes a large hinge ring 231 and a small hinge ring 232. The large hinge ring 231 is hung on the protrusion 221 to restrict the position of the restraint net 23 and the corner armor plate 22. The small hinge ring 232 corresponds to the cable axis. The large hinge ring 231 is symmetrically arranged along the small hinge ring 232. The small hinge ring 232 reduces the influence on the bending ability of the cable in the short side direction.

[0035] When bending is required during installation, the two outer recessed grooves 12 are held in place with fingers, and the conductor 8 is squeezed inwards while bending. This causes the deformation wall 111 to be squeezed out to form a protruding bulge. This bulge is used to elevate the cable and increase the curvature when bending, thereby providing some protection for the internal conductor 8. When bending, one side of the horizontal plane will contract while the other side will stretch. When stretching, the deformation wall 111 moves closer to the deformation groove 11, and the two outer recessed grooves 12 compensate for the deformation wall 111. Glue can also be squeezed into the deformation groove 11 during installation to maintain the bending angle and the formation of the bulge. During bending, the binding net 23 serves as the base of the outer sheath 1, limiting the maximum deformation of the outer sheath 1 to prevent cracking due to excessive deformation. When subjected to pressure or impact, the corner armor plates 22, binding net 23, and metal wire 21 provide protection, and the corner blocks 9 share the pressure to protect the internal cable tray 81.

[0036] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A high-current flexible medium-voltage explosion-proof cable, characterized in that, The cable includes a rectangular conductor (8), which is formed by horizontally stacking several wire strips (81). The wire strips (81) have wire grooves arranged in a linear array. The conductor (8) has arc-shaped corner blocks (9) on both sides. The corner blocks (9) fit into multiple wire strips (81) to form rounded corners at the edges of the cable.

2. The high-current flexible medium-voltage explosion-proof cable according to claim 1, characterized in that, The conductor (8) is provided with conductor shield, polypropylene shield (7), insulation shield (6), metal shield (5), inner wrapping layer (4), inner sheath (3), armor layer (2) and outer sheath (1) in sequence.

3. The high-current flexible medium-voltage explosion-proof cable according to claim 2, characterized in that, The outer sheath (1) has deformation grooves (11) arranged in a linear array in both horizontal directions.

4. A high-current flexible medium-voltage explosion-proof cable according to claim 3, characterized in that, The outer sheath (1) is symmetrically provided with outer recessed grooves (12) along the deformation groove (11), and a deformation wall (111) serving as the inner wall of the deformation groove (11) is provided between the two outer recessed grooves (12).

5. A high-current flexible medium-voltage explosion-proof cable according to claim 2, characterized in that, The armor layer (2) includes metal wires (21) spirally wound along the inner sheath (3).

6. A high-current flexible medium-voltage explosion-proof cable according to claim 5, characterized in that, The armor layer (2) includes corner armor plates (22) arranged along the diagonal.

7. A high-current flexible medium-voltage explosion-proof cable according to claim 6, characterized in that, The inner wall of the corner armor plate (22) is provided with an inlay groove (223) corresponding to the metal wire (21).

8. A high-current flexible medium-voltage explosion-proof cable according to claim 6, characterized in that, The corner armor plate (22) includes a vertical surface, and the vertical surface is provided with opposing horizontal steps (222).

9. A high-current flexible medium-voltage explosion-proof cable according to claim 6, characterized in that, The outer layer of the corner armor plate (22) is provided with a binding net (23), which is embedded in the outer sheath (1).

10. A high-current flexible medium-voltage explosion-proof cable according to claim 9, characterized in that, The outer layer of the corner armor plate (22) is provided with protrusions (221), and the binding net (23) includes a large hinge ring (231) and a small hinge ring (232), with the large hinge ring (231) hanging on the protrusions (221).

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