Low-voltage fire-resistant cable

Abstract

The utility model discloses a low-voltage fire-resistant cable, which belongs to the technical field of cables and comprises a heat-resistant pipe, a plurality of electric insulation pipes are arranged on the inner side of the heat-resistant pipe, wires are arranged on the inner sides of the plurality of electric insulation pipes, a plurality of inner heat-conducting holes are arranged in the electric insulation pipes, and a plurality of outer heat-conducting holes are arranged in the inner heat-conducting holes. Flame-retardant filler is arranged between the heat resisting pipe and the electric insulation pipes, a plurality of heat conduction boxes are arranged in the flame-retardant filler, and the outer side faces of the heat conduction boxes are attached to the outer side faces of the electric insulation pipes respectively. According to the utility model, heat generated by operation of the lead is conducted through the inner heat conduction holes in the electric insulation tube, so that the heat is discharged out of the cable from the inner heat conduction holes in the end part of the cable, the heat conduction box is arranged in the flame-retardant filler, and the side surface of the heat conduction box is in contact with the electric insulation tube. The water in the heat conduction box is used for cooling the surface of the electric insulation pipe, so that the electric insulation pipe is cooled.

Description

Technical Field

[0001] The utility model relates to the technical field of cables, and more specifically to a low-voltage fire-resistant cable. Background Art

[0002] A cable is a conductor covered with an insulating layer, a protective layer, a shielding layer, etc., used to transmit electric power or signal current or signal voltage. It can be divided into high-voltage cables and low-voltage cables according to voltage. Although low-voltage cable lines are more expensive and more difficult to lay and maintain than low-voltage overhead lines and low-voltage overhead insulated lines, they are widely used in low-voltage power distribution systems because of their reliable operation, no need for poles, no ground occupation, no obstruction of sight, and little influence from the outside world.

[0003] After searching, the utility model patent with announcement number CN220137993U discloses a low-voltage fire-resistant cable, including at least two conductors arranged in parallel, a heat-resistant layer coated on the outside of each conductor, an expansion insulation unit coated on the outside of each heat-resistant layer, and a sheath coated on the outside of the expansion insulation unit. The expansion insulation unit includes a metal layer, an expansion layer coated on the outside of the metal layer, and a protective layer coated on the outside of the expansion layer. The expansion layer is a mixture of refractory mud and vermiculite; the low-voltage fire-resistant cable can increase the thickness of the fire-resistant layer on the outside of the conductor through the expansion of the expansion layer, which can effectively extend the fire-resistant time and has strong practicality.

[0004] However, the above patent has the following shortcomings: when the outer part of the sheath is burned by flames, the heat it receives is easily transferred to the inner part, thus affecting the internal structure; and when the heat insulation unit is set to isolate the external heat from transferring to the wire, it will also cause the heat generated by the wire during conduction to be difficult to dissipate, affecting the use of the cable. For this reason, we propose a low-voltage fire-resistant cable. Utility Model Content

[0005] In view of the problems existing in the prior art, the utility model aims to provide a low-voltage fire-resistant cable.

[0006] In order to solve the above problems, the utility model adopts the following technical solutions:

[0007] A low-voltage fire-resistant cable comprises a heat-resistant tube, a plurality of electrical insulating tubes are arranged on the inner side of the heat-resistant tube, a conductor is arranged on the inner side of each of the plurality of electrical insulating tubes, a plurality of inner heat-conducting holes are opened inside the electrical insulating tube, a flame-retardant filler is arranged between the heat-resistant tube and the electrical insulating tube, a plurality of heat-conducting boxes are arranged inside the flame-retardant filler, the outer side surfaces of the heat-conducting boxes are respectively fitted with the outer side surfaces of the plurality of electrical insulating tubes, the inner cavity of the heat-conducting box is provided with cooling water, a metal hose is fixedly sleeved on the outer side of the heat-resistant tube, and an outer fire-resistant layer is arranged on the outer side of the metal hose.

[0008] As a preferred solution of the utility model, the outer fire-resistant layer includes an expansion layer fixedly sleeved on the outside of the metal hose, a glass fiber layer is arranged on the outside of the expansion layer, a mica tape is wrapped on the outside of the glass fiber layer, a sheath is fixedly sleeved on the outside of the mica tape wrap, a plurality of heat dissipation holes are provided on the outside of the sheath, a plurality of heat conduction ring grooves are provided on the inside of the sheath, and a plurality of external heat conduction holes are provided on the inside of the sheath.

[0009] As a preferred solution of the utility model, the sheath is made of silicone rubber.

[0010] As a preferred solution of the utility model, the expansion layer is a combination of refractory mud and vermiculite.

[0011] As a preferred solution of the utility model, the heat dissipation hole, the external heat conduction hole and the inner cavity of the heat conduction ring groove are connected.

[0012] As a preferred solution of the utility model, the metal hose is woven from metal wires.

[0013] Compared with the prior art, the advantages of the present invention are:

[0014] (1) In the utility model, the heat generated by the running of the wire is conducted through the internal heat conduction hole in the electric insulating tube, so that the heat is discharged to the outside from the internal heat conduction hole at the end of the cable. In addition, a heat conduction box is arranged inside the flame retardant filler, and the side of the heat conduction box is in contact with the electric insulating tube. The water in the heat conduction box is used to cool the surface of the electric insulating tube, thereby cooling the electric insulating tube, which has good practicality.

[0015] (2) In the utility model, the outer side of the cable is fireproofed by a sheath made of silicone rubber. The heat received by the sheath is conducted through the external heat conduction holes and the heat conduction ring grooves, and the heat is discharged by the heat dissipation holes at the non-flame burning position on the outer side of the sheath, thereby ensuring the service life of the sheath. When the sheath is damaged, the mica tape is used for fireproofing. When the mica tape is damaged, the expansion layer is heated and the vermiculite therein expands to seal the damaged part of the mica tape. The metal hose inside the expansion layer can also be used for fireproofing, thereby improving the working quality of the low-voltage fire-resistant cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0017] Figure 2 It is a cross-sectional schematic diagram of the utility model;

[0018] Figure 3 This is a schematic diagram of the structure of the metal hose of the utility model;

[0019] Figure 4It is a structural schematic diagram of the heat conduction box of the utility model;

[0020] Figure 5 For this utility model Figure 2 A is an enlarged schematic diagram.

[0021] Description of the numbers in the figure:

[0022] 1. Heat-resistant tube; 2. Electrical insulation tube; 3. Wire; 4. Internal heat-conducting hole; 5. Flame-retardant filler; 6. Heat-conducting box; 7. Metal hose; 8. External fire-resistant layer; 9. Expansion layer; 10. Glass fiber layer; 11. Mica tape wrapping; 12. Sheath; 13. Heat dissipation hole; 14. External heat-conducting hole; 15. Heat-conducting ring groove. DETAILED DESCRIPTION

[0023] The following will clearly and completely describe the technical solutions in the embodiments of the utility model in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0025] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "set / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0026] Example:

[0027] See also Figure 1-5A low-voltage fire-resistant cable comprises a heat-resistant tube 1, a plurality of electrical insulating tubes 2 are arranged on the inner side of the heat-resistant tube 1, a conductor 3 is arranged on the inner side of each of the plurality of electrical insulating tubes 2, a plurality of inner heat-conducting holes 4 are opened inside the electrical insulating tube 2, a flame-retardant filler 5 is arranged between the heat-resistant tube 1 and the electrical insulating tube 2, a plurality of heat-conducting boxes 6 are arranged inside the flame-retardant filler 5, the outer side surfaces of the heat-conducting boxes 6 are respectively fitted with the outer side surfaces of the plurality of electrical insulating tubes 2, cooling water is arranged in the inner cavity of the heat-conducting boxes 6, a metal hose 7 is fixedly sleeved on the outer side of the heat-resistant tube 1, and an outer fire-resistant layer 8 is arranged on the outer side of the metal hose 7.

[0028] In this embodiment, the direction of the plurality of inner heat conducting holes 4 is the same as the length direction of the wire 3 .

[0029] For details, please refer to Figure 1 and Figure 5 The outer fire-resistant layer 8 includes an expansion layer 9 fixedly sleeved on the outside of the metal hose 7, a glass fiber layer 10 is arranged on the outside of the expansion layer 9, a mica tape wrap 11 is arranged on the outside of the glass fiber layer 10, a sheath 12 is fixedly sleeved on the outside of the mica tape wrap 11, a plurality of heat dissipation holes 13 are provided on the outside of the sheath 12, a plurality of heat conduction ring grooves 15 are provided inside the sheath 12, and a plurality of external heat conduction holes 14 are provided inside the sheath 12.

[0030] In this embodiment, the glass fiber layer 10 is arranged in a folded wave pattern, and the direction of the external heat conducting hole 14 is the same as the length direction of the sheath 12 .

[0031] For details, please refer to Figure 1 , the sheath 12 is made of silicone rubber.

[0032] In this embodiment, the heat resistance of silicone rubber is very outstanding. It can work for a long time at 180°C, and can withstand temperatures slightly above 200°C for several weeks or longer while still being elastic. It can instantly withstand high temperatures above 300°C, and can achieve fire protection from the outside.

[0033] For details, please refer to Figure 1 The expansion layer 9 is a combination of refractory mud and vermiculite.

[0034] In this embodiment, vermiculite is a mineral that expands under high temperature. When the sheath 12, the mica tape wrap 11 and the glass fiber layer 10 are damaged, the vermiculite in the expansion layer 9 expands to seal the damaged area.

[0035] For details, please refer to Figure 5 The heat dissipation hole 13, the external heat conduction hole 14 and the inner cavity of the heat conduction ring groove 15 are connected.

[0036] In this embodiment, it is ensured that the high temperature to which the sheath 12 is exposed can flow through the heat dissipation holes 13, the external heat conduction holes 14 and the heat conduction ring grooves 15, so as to dissipate the heat from the heat dissipation holes 13 on the surface of other locations exposed to the flame.

[0037] For details, please refer to Figure 2 The metal hose 7 is woven from metal wires.

[0038] In this embodiment, the material of the metal wire can be SUS304, SUS321, SUS316, which has the function of resisting high temperature and high pressure.

[0039] Working principle: When in use, first, when the outer side of the cable is burned by flames, the sheath 12 made of silicone rubber is fireproof. In addition, the heat in the sheath 12 is conducted through the external heat conduction holes 14 and the heat conduction ring grooves 15, and the heat is discharged through the heat dissipation holes 13 at the non-flame burning position on the outer side of the sheath 12. When the sheath 12 is damaged, the mica tape wrap 11 is used for fire resistance. When the mica tape wrap 11 is damaged, the expansion layer 9 is heated and the vermiculite therein expands to seal the damaged part of the mica tape wrap 11. In addition, the metal hose 7 inside the expansion layer 9 can also be used for fire resistance.

[0040] In addition, when the wire 3 is running, the heat generated by the wire 3 is introduced into the electrical insulating tube 2, and the heat is conducted by the internal heat conduction hole 4 in the electrical insulating tube 2, so that the heat is discharged from the position where the end of the internal heat conduction hole 4 is connected to the outside, and at the same time, the cooling water in the heat conduction box 6 is used to cool the outside of the electrical insulating tube 2, so as to cool the wire 3.

[0041] The above is only a preferred specific implementation method of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or changes within the technical scope disclosed by the utility model according to the technical solution and improved ideas of the utility model, which should be included in the protection scope of the utility model.

Claims

1. A low-voltage fire-resistant cable, comprising a heat-resistant tube (1), characterized in that: A plurality of electrical insulating tubes (2) are arranged on the inner side of the heat-resistant tube (1), and a conductor (3) is arranged on the inner side of each of the plurality of electrical insulating tubes (2). A plurality of internal heat-conducting holes (4) are opened inside the electrical insulating tube (2). A flame-retardant filler (5) is arranged between the heat-resistant tube (1) and the electrical insulating tube (2). A plurality of heat-conducting boxes (6) are arranged inside the flame-retardant filler (5), and the outer side surfaces of the heat-conducting boxes (6) are respectively fitted with the outer side surfaces of the plurality of electrical insulating tubes (2). Cooling water is arranged in the inner cavity of the heat-conducting boxes (6). A metal hose (7) is fixedly sleeved on the outer side of the heat-resistant tube (1), and an outer fire-resistant layer (8) is arranged on the outer side of the metal hose (7); The outer fire-resistant layer (8) comprises an expansion layer (9) fixedly sleeved on the outside of the metal hose (7); a glass fiber layer (10) is arranged on the outside of the expansion layer (9); a mica tape wrap (11) is arranged on the outside of the glass fiber layer (10); a sheath (12) is fixedly sleeved on the outside of the mica tape wrap (11); a plurality of heat dissipation holes (13) are provided on the outside of the sheath (12); a plurality of heat conduction ring grooves (15) are provided on the inside of the sheath (12); and a plurality of external heat conduction holes (14) are provided on the inside of the sheath (12).

2. A low voltage fire resistant cable according to claim 1, characterized in that: The sheath (12) is made of silicone rubber.

3. A low voltage fire resistant cable according to claim 1, characterized in that: The heat dissipation hole (13), the external heat conduction hole (14) and the inner cavity of the heat conduction ring groove (15) are connected.

4. A low voltage fire resistant cable according to claim 1, characterized in that: The metal hose (7) is braided from metal wires.

Images