Temperature-sensing flame-retardant cable

Abstract

The utility model relates to the technical field of cables, in particular to a temperature-sensing flame-retardant cable, which comprises an outer sheath, a temperature-sensing optical fiber and at least one wire core. The wire core and the temperature sensing optical fiber are twisted and are arranged in the outer sheath; and the output end of the temperature sensing optical fiber is connected with the input end of the temperature detection equipment.

Description

TECHNICAL FIELD

[0001] The utility model relates to cable technical field, concretely relates to a temperature sensing flame-retardant cable. BACKGROUND

[0002] With the continuous improvement of the dependence of modern society on electric power energy, electric wire and cable as the core carrier of electric energy transmission has been widely used in various building facilities and industrial sites. The pyrolysis reaction of traditional cable organic insulation materials such as polyvinyl chloride and polyethylene easily occurs under high temperature environment, and its combustion process not only releases strong toxic gases such as hydrogen chloride and carbon monoxide, but also produces a large amount of smoke to block the escape channel. More seriously, the abnormal temperature rise of cable line in the initial stage of fire is often not discovered in time, which leads to the continuous overheating operation of the power supply system until the insulation failure. This unmonitored abnormal state may cause electric arc discharge and trigger the explosion accident.

[0003] At present, the flame-retardant cable technology mainly focuses on the improvement of the flame-retardant performance of materials, such as using flame-retardant PVC or XLPE outer sheath to delay combustion through the high oxygen index of the material itself, or filling mica tape and other inorganic flame-retardant materials in the core gap. However, such schemes have two key technical defects: first, there is no real-time temperature monitoring mechanism, which cannot send early warning signals before the insulation material enters the critical temperature of thermal decomposition, resulting in the loss of the best disposal opportunity for the operation and maintenance personnel; second, the traditional flame-retardant materials will still decompose and carbonize under the condition of continuous high temperature, especially when the environmental temperature exceeds the limit oxygen index of the material, the flame-retardant efficiency will be significantly reduced. Therefore, the electric wire and cable without temperature monitoring system still cannot be intervened and prevented in time when the temperature abnormally rises, which is easy to cause fire and cause serious personnel and property losses. SUMMARY

[0004] The utility model provides a temperature sensing flame-retardant cable to overcome the above-mentioned defects of lacking temperature monitoring.

[0005] To solve the above technical problems, the technical scheme of the utility model is as follows:

[0006] A temperature sensing flame-retardant cable, comprising an outer sheath, a temperature sensing optical fiber and at least one core; the core is twisted with the temperature sensing optical fiber and arranged inside the outer sheath; the output end of the temperature sensing optical fiber is connected with the input end of a temperature detection device.

[0007] As a preferred scheme, the core comprises a conductor wrapped with an insulation layer.

[0008] As a preferred scheme, the conductor comprises a single copper wire or a plurality of twisted copper wires.

[0009] As a preferred scheme, the insulation layer is made of flame-retardant polymer material.

[0010] As a preferred solution, the wire core is uniformly distributed in the outer sheath in a circumferential direction, and the temperature sensing fiber is arranged at the center of the outer sheath.

[0011] As a preferred solution, a filling layer is arranged between the wire core and the temperature sensing fiber in the outer sheath.

[0012] As a preferred solution, the filling layer comprises aramid yarn, polyester fiber or glass fiber.

[0013] As a preferred solution, the inner surface of the outer sheath is provided with a signal shielding layer.

[0014] As a preferred solution, a protective layer is further arranged between the wire core and the signal shielding layer.

[0015] As a preferred solution, the signal shielding layer comprises a copper strip or a copper wire.

[0016] Compared with the prior art, the beneficial effects of the technical scheme of the utility model are:

[0017] The utility model discloses a temperature sensing fiber real-time output temperature signal to temperature monitoring equipment, can through temperature monitoring equipment real-time monitoring cable operation temperature real-time temperature monitoring, can timely find cable temperature abnormal condition, provides effective guarantee for preventing the fire caused by cable overheating, reduces the damage, fire and other accidents of cable due to overheating, ensures the stable operation of electrical system. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a temperature sensing flame-retardant cable structure schematic diagram.

[0019] Figure 2 It is a temperature sensing flame-retardant cable structure schematic diagram when the single wire core.

[0020] Wherein, 1-outer sheath, 2-temperature sensing fiber, 3-insulation layer, 4-conductor, 5-filling layer. 6-shielding layer. 7-protective layer. DETAILED DESCRIPTION

[0021] The drawings are only used for illustrative description, and can not be understood as the limitation of the patent;

[0022] In order to better illustrate the embodiment, some components of the drawings can be omitted, enlarged or reduced, and do not represent the size of the actual product;

[0023] For those skilled in the art, it is understandable that some known structures in the drawings and their descriptions can be omitted.

[0024] The technical scheme of the utility model will be further described below in combination with the drawings and embodiments.

[0025] Embodiment 1

[0026] The embodiment provides a temperature-sensing flame-retardant cable, which comprises an outer sheath 1, a temperature-sensing optical fiber 2 and at least one core. Figure 1 As shown in the figure, it is a temperature-sensing flame-retardant cable structure schematic diagram.

[0027] The embodiment provides a temperature-sensing flame-retardant cable, which comprises an outer sheath 1, a temperature-sensing optical fiber 2 and at least one core.

[0028] As an example, the temperature-sensing optical fiber 2 is a luminescent optical fiber, and the outer sheath 1 is made of high-flame-retardant halogen-free low-smoke flame-retardant polyolefin material.

[0029] In the embodiment, the temperature-sensing optical fiber 2 is integrated in the outer sheath 1, the internal temperature distribution of the cable is monitored in real time, when the local temperature of the cable is abnormal due to overload or external fire source, the temperature-sensing optical fiber 2 can transmit the temperature signal to the monitoring device, and the early warning or linkage fire extinguishing system is triggered.

[0030] In the embodiment, the temperature-sensing optical fiber 2 is integrated in the outer sheath 1, the internal temperature distribution of the cable is monitored in real time, when the local temperature of the cable is abnormal due to overload or external fire source, the temperature-sensing optical fiber 2 can transmit the temperature signal to the monitoring device, and the early warning or linkage fire extinguishing system is triggered. Figure 1 As shown in the figure, it is a schematic diagram of the temperature-sensing flame-retardant cable after the multi-core is twisted with the temperature-sensing optical fiber. Figure 2 As shown in the figure, it is a schematic diagram of the temperature-sensing flame-retardant cable when the single-core is twisted.

[0031] Embodiment 2

[0032] The embodiment refines the core structure on the basis of the temperature-sensing flame-retardant cable provided in the embodiment 1.

[0033] The embodiment provides a temperature-sensing flame-retardant cable, which comprises an outer sheath 1, a temperature-sensing optical fiber 2 and at least one core.

[0034] In an optional embodiment, the core comprises a conductor 4 wrapped by an insulating layer 3.

[0035] As an example, the insulating layer 3 is made of irradiation crosslinking halogen-free low-smoke flame-retardant polyolefin material.

[0036] As another example, the conductor 4 is twisted by oxygen-free soft copper wire, and the conductor meets the second copper conductor specified in the national standard.

[0037] In the embodiment, the core arranged in the outer sheath 1 has the insulating layer 3 on the outer surface and the conductor 4 in the inner part, so that the functional requirements of power transmission or signal transmission are met.

[0038] Further optionally, the conductor 4 comprises a single or multiple copper wires.

[0039] In this embodiment, by selecting a single or multiple copper wires as the conductor 4, the structure of the conductor 4 can be flexibly selected according to the current carrying capacity requirements and mechanical performance requirements of different application occasions; wherein the multiple copper wire conductor 4 improves the flexibility of the conductor 4 through the twisting process, reduces the stress concentration when the cable is bent, and reduces the risk of wire breakage; it also increases the heat dissipation surface area and relieves the current carrying temperature rise. The single copper wire structure is simple, the manufacturing process is relatively mature, and the cost is relatively low, and it is more reliable in occasions that need to bear larger tension or higher stability. Secondly, the single conductor 4 does not increase the resistance caused by twisting, and is suitable for application occasions that require lower resistance and high efficiency current conduction.

[0040] Further optionally, the insulating layer 3 is made of a flame-retardant polymer material.

[0041] In this embodiment, the insulating layer 3 made of a flame-retardant polymer is arranged outside the conductor 4, which has good flame-retardant properties while meeting the insulation performance, and can form a dense carbonized layer at high temperature to block the transmission path of oxygen and heat, and inhibit the spread of fire caused by short circuit between the cores.

[0042] Embodiment 3

[0043] This embodiment improves the temperature sensing flame-retardant cable proposed in Embodiment 1 or Embodiment 2.

[0044] The temperature sensing flame-retardant cable proposed in this embodiment comprises an outer sheath 1, a temperature sensing optical fiber 2 and at least one core; the core is twisted with the temperature sensing optical fiber 2 and arranged inside the outer sheath 1; the output end of the temperature sensing optical fiber 2 is connected with the input end of a temperature detection device.

[0045] In an optional embodiment, the cores are uniformly distributed in the circumferential direction inside the outer sheath 1, and the temperature sensing optical fiber 2 is placed at the center of the outer sheath 1.

[0046] In this embodiment, the cores are arranged in a circumferential manner, which can make the overall stress distribution of the cable uniform, reduce internal structural deformation, balance the radial stress of the outer sheath 1, and avoid damage to the sheath caused by unilateral extrusion; at the same time, the temperature sensing optical fiber 2 is placed in the center, which can ensure that the heat conduction paths from all directions to the optical fiber are approximately the same, obtain more accurate temperature data, improve the accuracy and response speed of temperature monitoring, reduce internal interference of the cable, and thus prolong the service life of the cores and the optical fiber.

[0047] In an optional embodiment, a filling layer 5 is arranged between the core and the temperature sensing optical fiber 2 inside the outer sheath 1.

[0048] In this embodiment, the filling layer 5 is added inside the outer sheath 1, which can keep the relative position between the core and the temperature sensing fiber 2 stable, avoid mutual extrusion or friction damage, and further improve the overall temperature resistance and safety of the cable.

[0049] Further optionally, the filling layer 5 comprises aramid yarn, polyester fiber or glass fiber.

[0050] In this embodiment, the selection of appropriate filling materials can not only provide mechanical cushioning protection for the temperature sensing fiber 2, but also delay the spread of fire as a fire-retardant barrier.

[0051] Embodiment 4

[0052] This embodiment is an improvement on the temperature sensing fire-retardant cable proposed in Embodiments 1-3.

[0053] The temperature sensing fire-retardant cable proposed in this embodiment comprises an outer sheath 1, a temperature sensing fiber 2 and at least one core; the core and the temperature sensing fiber 2 are twisted and arranged inside the outer sheath 1; the output end of the temperature sensing fiber 2 is connected to the input end of a temperature detection device.

[0054] In an optional embodiment, the inner surface of the outer sheath 1 is provided with a signal shielding layer 6.

[0055] In this embodiment, by adding a shielding layer to the inner surface of the outer sheath 1 of the cable, the interference of the external electromagnetic field on the internal core and the temperature sensing fiber 2 is effectively reduced, and the external radiation of the internal high-frequency signal is inhibited. Specifically, the shielding layer reflects or absorbs external electromagnetic waves, and guides the induced current or noise signal to the ground or reference ground, avoiding the generation of coupling interference in the temperature sensing fiber 2 and the core, and ensuring accurate temperature detection and stable signal transmission in a high-interference environment.

[0056] Further optionally, a protective layer 7 is further arranged between the core and the signal shielding layer 6.

[0057] As an exemplary illustration, the protective layer 7 is a halogen-free low-smoke fire-retardant material.

[0058] In this embodiment, a layer of physically and electrically isolated protective layer 7 is arranged between the signal shielding layer 6 and the core, which can effectively reduce the wear of the metal edges or braided parts of the shielding layer on the core and the filling layer 5; at the same time, it reduces unnecessary coupling between the high-frequency signal in the core and the shielding layer, improves the overall firmness and durability of the cable structure, and in addition, the protective layer 7 can also block the electrochemical corrosion between the core and the shielding layer.

[0059] Further optionally, the signal shielding layer 6 comprises a copper strip or a copper wire.

[0060] As an example, the copper tape coverage is 45-50%, and the copper wire weaving density is greater than 90%.

[0061] In this embodiment, the overall anti-interference capability of the cable can be significantly improved by using copper material. The copper tape or copper wire weaving structure can be selected according to the application requirements. Specifically, the copper tape has a complete and continuous metal shielding surface, which is suitable for occasions with high shielding requirements; the copper wire weaving has greater flexibility, lighter weight, and is also convenient to use in dynamic bending environment.

[0062] Embodiment 5

[0063] In this embodiment, a temperature-sensing flame-retardant cable is made according to the temperature-sensing flame-retardant cable proposed in embodiments 1-4.

[0064] Select high-purity copper rods or oxygen-free copper rods, and get single copper wire of the required diameter by wire drawing. According to the use environment and current level requirements, a plurality of single copper wires can be twisted to obtain the conductor 4. After obtaining the conductor 4, the flame-retardant polymer material is extruded or coated as the insulating layer 3. The temperature-sensing optical fiber 2 is fixed at a reserved position to avoid bending, breaking or heat damage of the optical fiber during subsequent cabling or sheath extrusion. According to the required core number and structure, aramid yarn, polyester fiber or glass fiber is selected as the filler layer 5, and the wire core and temperature-sensing optical fiber 2 are twisted while arranged in a specific arrangement by a cabling machine. Then, before the outer sheath 1 is extruded, a copper tape or copper wire woven signal shielding layer 5 can be added on the surface of the cable according to the requirements, and then the outer sheath 1 is extruded and coated on the basis of the original wire core.

[0065] The temperature-sensing flame-retardant cable proposed in this embodiment has a wide range of applications, such as:

[0066] (1) Fire monitoring in high-rise buildings: The cable is used for power distribution and fire monitoring in key lines in buildings. Once the local temperature reaches the dangerous threshold, the temperature abnormal point can be quickly found and located through the temperature-sensing optical fiber, which assists the fire control system to start in time.

[0067] (2) Tunnel and subway engineering: The temperature-sensing flame-retardant cable is used in the ventilation system, monitoring device and power line of underground engineering, which can effectively reduce the fire risk and monitor the temperature inside the tunnel and the track area in real time.

[0068] (3) Petrochemical and chemical sites: In flammable and explosive environments, real-time temperature sensing and flame-retardant properties of the cable can provide early warning before leakage or temperature loss of control, which helps personnel to evacuate in time and remotely control in emergency.

[0069] (4) Server room and data center: Large-scale server clusters need to be accurately monitored for temperature. The cable can be used to simultaneously complete power transmission and temperature detection, ensuring that the cabinet and server work in a relatively stable temperature range.

[0070] The same or similar reference signs correspond to the same or similar components;

[0071] The terms describing the positional relationship in the drawings are only used for illustrative description, and should not be understood as a limitation on the patent;

[0072] Obviously, the above embodiments of the present application are only examples for clearly illustrating the present application, and are not a limitation on the embodiments of the present application. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, it is not necessary and impossible to enumerate all the embodiments. Any modification, equivalent replacement and improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the claims of the present application.

Claims

1. A thermally sensitive flame retardant cable, characterized in that The cable comprises an outer sheath (1), a temperature sensing fiber (2) and at least one core; the core is twisted with the temperature sensing fiber (2) and arranged inside the outer sheath (1); the output end of the temperature sensing fiber (2) is connected with the input end of a temperature detecting device.

2. A fire survival temperature sensitive cable according to claim 1, characterised in that, The core comprises a conductor (4) wrapped with an insulating layer (3).

3. A fire survival temperature sensitive cable according to claim 2, characterised in that, The conductor (4) comprises a single copper wire or a plurality of twisted copper wires.

4. A fire survival temperature sensitive cable according to claim 2, characterised in that, The insulating layer (3) is made of a flame-retardant polymer material.

5. A fire survival temperature sensitive cable according to claim 1, characterised in that, The core is uniformly distributed in the outer sheath (1) in a circumferential direction, and the temperature sensing fiber (2) is arranged at the center of the outer sheath (1).

6. A fire survival temperature sensitive cable according to claim 5, characterised in that, A filling layer (5) is arranged between the core and the temperature sensing fiber (2).

7. A fire survival temperature sensitive cable according to claim 6, characterised in that, The filling layer (5) comprises aramid yarn, polyester fiber or glass fiber.

8. A fire survival temperature limited electrical cable according to any one of claims 1 to 7, characterised in that, An inner surface of the outer sheath (1) is provided with a signal shielding layer (6).

9. A fire survival temperature sensitive cable according to claim 8, characterised in that, A protective layer (7) is further arranged between the core and the signal shielding layer (6).

10. A fire survival temperature limited electrical cable according to claim 8, characterised in that, The signal shielding layer (6) comprises a copper strip or a copper wire.

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