Intelligent monitoring high-flame-retardant water-blocking long-distance symmetric communication cable

Abstract

The invention discloses an intelligent monitoring high-flame-retardant water-blocking long-distance symmetrical communication cable, which comprises a communication line group, a plurality of intelligent monitoring units, a flame-retardant structure, a water-blocking structure, a shielding structure, an oxygen isolation structure and an outer sheath, and is characterized in that the plurality of intelligent monitoring units are uniformly distributed along the length direction of the communication line group and form a cable core together with the communication line group; the flame-retardant structure, the water-blocking structure, the shielding structure and the flame-retardant oxygen-isolating structure are all arranged between the cable core and the outer sheath, the intelligent monitoring unit comprises a monitoring module, a data processing module and a communication module, and the monitoring module is composed of a temperature sensor, a humidity sensor, a strain sensor and a current monitor. The data processing module is electrically connected with the monitoring module on one hand, and communicates with a remote monitoring center through the communication module on the other hand, so that moisture can be effectively prevented from invading into the cable, and the cable has good transmission performance, monitoring function and water-blocking and flame-retardant performance, and can autonomously monitor the operation state and perform early warning and positioning on faults.

Description

Technical Field

[0001] The present invention relates to the technical field of communication cables, in particular to the technical field of long-distance symmetrical communication cables. Background Art

[0002] Long-distance symmetrical communication cable is a communication cable that uses symmetrical cable as the transmission medium; long-distance symmetrical communication cable has the characteristics of fast signal transmission speed, small signal distortion and strong anti-interference ability. It can be used normally in electrified railway sections, electric traction power supply systems or under strong electrical interference conditions. It can ensure the stability and reliability of signal transmission and is widely used in telecommunications, radio and television, network communications and railway communications.

[0003] With the rapid development of communication technology, the coverage of long-distance communication networks is constantly expanding, and people's performance requirements for communication cables are becoming increasingly stringent. Traditional long-distance symmetrical communication cables are simply waterproof and fireproofed by water-blocking tapes and thermal insulation layers, such as the highly flame-retardant oil-filled long-distance symmetrical communication cable with announcement number CN215342089U, a railway long-distance symmetrical communication cable with announcement number CN206163190U, and a railway long-distance symmetrical communication cable with announcement number CN208521681U. Such long-distance symmetrical communication cables are vulnerable to fire hazards, humid environments, and line faults. When using such cables, many limitations are exposed; specifically, in some complex geographical environments and harsh climatic conditions, such long-distance symmetrical communication cables are susceptible to water immersion, which may cause signal transmission interruption or short-circuit failure; once a fire occurs, traditional water-blocking long-distance symmetrical communication cables may burn and spread rapidly (which will not only cause communication interruption, but may also cause serious safety accidents); in addition, such long-distance symmetrical communication cables lack effective self-monitoring methods, making it difficult for maintenance personnel to promptly detect and locate faults in the early stages of the fault, which brings great difficulties and costs to the maintenance and repair of communication networks. Summary of the invention

[0004] The purpose of the present invention is to solve the problems in the prior art and to propose an intelligent monitoring, highly flame-retardant and water-resistant long-distance symmetrical communication cable, which can not only effectively prevent moisture from invading the interior of the cable, but also has good transmission performance, monitoring function and water-resistant and flame-retardant properties, but can also autonomously monitor the operating status and provide early warning and positioning of faults, so as to facilitate timely discovery and resolution of problems, reduce communication interruption time, and improve the security, reliability and maintenance efficiency of the communication network. It is very suitable for rail transit signal control systems and has broad market prospects.

[0005] To achieve the above-mentioned purpose, the present invention proposes an intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable, comprising a communication line group, an intelligent monitoring unit, a flame-retardant structure, a water-resistant structure, a shielding structure, an oxygen-isolating structure and an outer sheath. A plurality of the intelligent monitoring units are evenly distributed along the length direction of the communication line group and together with the communication line group constitute a cable core. The flame-retardant structure, the water-resistant structure, the shielding structure and the flame-retardant and oxygen-isolating structure are all arranged between the cable core and the outer sheath. The intelligent monitoring unit comprises a monitoring module, a data processing module and a communication module. The monitoring module is jointly composed of a temperature sensor, a humidity sensor, a strain sensor and a current monitor. The data processing module is electrically connected to the monitoring module on the one hand and communicates with a remote monitoring center through the communication module on the other hand.

[0006] Preferably, the communication line group is formed by twisting a number of communication wires in groups, the communication wires having a conductor drawn from high-precision oxygen-free copper wire with a diameter ranging from 0.902 to 0.905 mm and an extruded skin-to-skin physical foamed polyolefin insulation sheath wrapped around the conductor, the thickness of the inner skin layer of the skin-to-skin physical foamed polyolefin insulation sheath being controlled at 0.15±0.01 mm, the foaming degree of the foaming layer being controlled at 68±2%, and the thickness of the outer skin layer being controlled at 0.25±0.01 mm.

[0007] Preferably, the setting spacing of the intelligent monitoring units is controlled at 10 to 30 m, the temperature sensor adopts a thermistor sensor, the humidity sensor adopts a capacitive humidity sensor, the strain sensor adopts a fiber grating strain sensor, the current monitor adopts a current transformer, the data processing module adopts a Loongson 3C5000 microprocessor chip, and the communication module adopts a GC080X wireless communication chip.

[0008] Preferably, the flame retardant structure is a composite filler of magnesium hydroxide and cross-linked polyethylene filled in the gaps of the cable core, and the filling coefficient is controlled at 0.90-0.95.

[0009] Preferably, the water-blocking structure is composed of an expandable water-blocking grease filled in the gaps in the cable core and a first water-blocking tape and a second water-blocking tape sequentially arranged outside the cable core, wherein the first water-blocking tape and the second water-blocking tape are both composite films of a water-absorbing and expanding film and a waterproof film, and the expandable water-blocking grease is a mixed grease of a water-absorbing and expanding material and a basic waterproof grease.

[0010] Preferably, the first water-blocking tape and the second water-blocking tape are separated by a polyethylene insulation layer.

[0011] Preferably, the shielding structure is composed of an alloy aluminum sheath and a high magnetic permeability steel belt which are sequentially sleeved or wrapped around the second water-blocking tape from the inside to the outside. The thickness of the alloy aluminum sheath is 1.5 to 2.5 mm, the thickness of the high magnetic permeability steel belt is 0.3 to 0.8 mm, and the wrapping gap does not exceed 25%.

[0012] Preferably, the alloy aluminum sheath and the high magnetic permeability steel belt are separated by an insulating lining layer.

[0013] Preferably, the oxygen-isolating structure is composed of a first oxygen-isolating tape wrapped around the insulating lining layer and a second oxygen-isolating tape wrapped around the high-magnetic steel tape. Both the first oxygen-isolating tape and the second oxygen-isolating tape are low-smoke halogen-free glass fiber tapes with an oxygen index > 50 and a wrapping overlap rate > 25%.

[0014] Preferably, the outer sheath is a highly flame-retardant, low-smoke, halogen-free polyolefin sheath with an oxygen index > 36 and is extruded and coated outside the second oxygen-isolating tape. The thickness of the outer sheath is controlled at 2.0 to 2.1 mm, and the surface of the outer sheath is also provided with an anti-slip texture.

[0015] Beneficial effects of the present invention: 1) Intelligent monitoring function: The present invention sets several groups of intelligent monitoring units along the length direction, and can use each group of intelligent monitoring units to collect key parameters (temperature, humidity, strain and current) inside the cable core in real time at multiple points and transmit the data to the remote monitoring center through wireless communication technology, so that maintenance personnel can timely and accurately grasp the operation status of the cable, and can not only give early warning before the fault occurs, but also quickly locate the fault point after the fault occurs, effectively shortening the maintenance time and cost of the communication network, and improving the overall operation efficiency and reliability of the communication network; 2) Reliable water-blocking performance: The present invention uses an expandable water-blocking grease and a water-blocking tape to waterproof the inside and outside of the cable core, and the outer sheath itself also has a certain waterproof ability, thereby ensuring that the communication cable can still maintain good insulation performance and signal transmission performance in a humid environment or long-term water immersion conditions, greatly improving the applicability and reliability of the communication cable in complex geographical environments and harsh climatic conditions; 3) Excellent flame retardant performance: The present invention adopts flame retardant polyolefin material in the conductor insulation layer, magnesium hydroxide and cross-linked polyethylene composite filler in the cable core gap, double oxygen isolation design outside the cable core, and low-smoke halogen-free polyolefin material to prepare the outer sheath, so that the communication cable can effectively prevent the spread of flames when encountering fire, reduce the damage of fire to the communication network and the threat to the safety of life and property of personnel; 4) Good signal transmission performance: The present invention ensures that the communication cable has low attenuation and high anti-interference signal transmission characteristics during long-distance transmission by providing high-precision oxygen-free copper conductors, optimizing the wire group twist pitch and adopting a double-layer shielding design, thereby ultimately meeting the strict requirements of modern long-distance communications on signal quality and transmission rate.

[0016] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a cross-sectional view of the intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable of the present invention; Figure 2 It is a cross-sectional view of the cable core of the intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable of the present invention; Figure 3 It is a cross-sectional view of the communication conductor of the intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable of the present invention.

[0018] In the figure: 1-first water-blocking tape, 2-polyethylene insulation layer, 3-second water-blocking tape, 4-alloy aluminum sheath, 5-insulating lining layer, 6-first oxygen-isolating tape, 7-high magnetic steel tape, 8-second oxygen-isolating tape, 9-outer sheath, 10-communication line group, 101-conductor, 102-skin-skin physical foaming polyolefin insulation sleeve, 11-expandable water-blocking paste, 12-monitoring module, 13-composite filling material. DETAILED DESCRIPTION

[0019] See also Figure 1 , Figure 2 and Figure 3 The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable of the present invention comprises a communication line group 10, an intelligent monitoring unit, a flame-retardant structure, a water-resistant structure, a shielding structure, an oxygen-isolating structure and an outer sheath 9. A plurality of the intelligent monitoring units are evenly distributed along the length direction of the communication line group 10 and together with the communication line group 10 form a cable core. The flame-retardant structure, the water-resistant structure, the shielding structure and the flame-retardant oxygen-isolating structure are all arranged between the cable core and the outer sheath 9. The intelligent monitoring unit comprises a monitoring module 12, a data processing module and a communication module. The monitoring module 12 is jointly composed of a temperature sensor, a humidity sensor, a strain sensor and a current monitor. The data processing module is electrically connected to the monitoring module 12 on the one hand and communicates with a remote monitoring center through the communication module on the other hand.

[0020] The communication line group 10 is formed by twisting a plurality of communication wires in groups, and the communication wire has a conductor 101 drawn from high-precision oxygen-free copper wire with a diameter ranging from 0.902 to 0.905 mm, and a skin-foam-skin physical foamed polyolefin insulation sleeve 102 extruded and coated outside the conductor 101, wherein the thickness of the inner skin layer of the skin-foam-skin physical foamed polyolefin insulation sleeve 102 is controlled at 0.15±0.01 mm, the foaming degree of the foaming layer is controlled at 68±2%, and the thickness of the outer skin layer is controlled at 0.25±0.01 mm; Among them, polyolefin is a material with high temperature resistance, high insulation and low dielectric properties, and the communication line group 10 can also be twisted with a twisting pitch of 100 to 210 mm; this optimized design can not only improve the pressure resistance of the communication line group 10, improve the electrical insulation of the communication line group 10 (the working capacitance and characteristic impedance of the communication line group 10 are stable, the anti-interference ability is strong, and it has high communication clarity and stability), but also enable the communication line group 10 to have certain flame retardant properties (it can slow down the spread of flames when encountering high temperatures).

[0021] The spacing of the intelligent monitoring units is controlled at 10 to 30 m (e.g., one intelligent monitoring unit is set every 20 m); the temperature sensor adopts a thermistor sensor, which can monitor the temperature change of the cable core in real time (the measurement accuracy can reach 0.2°C), and when the temperature exceeds the set threshold, it will promptly issue an early warning signal so that maintenance personnel can discover the potential overheating fault of the cable in advance; the humidity sensor adopts a capacitive humidity sensor, which can accurately measure the humidity level of the cable core (relative humidity accuracy is ±2%), and once the humidity rises abnormally (which indicates that there may be a risk of flooding), the relevant information can be transmitted to the data processing module; the strain sensor adopts a fiber grating strain sensor, which can sense the tiny strain changes caused by the cable when it is stretched, squeezed or bent by external force, and the measurement range is from very small (0 to 0.1N) to very large (100t), so that the data processing module can determine whether the communication cable is mechanically damaged or subjected to abnormal external force by analyzing the strain data; the current monitor adopts a current transformer, which is used to monitor the magnitude and change of the current transmitted in the cable (accuracy level 0.2 level), and when the current fluctuates abnormally or is overloaded, it can promptly feedback to the data processing module; the data processing module adopts the Loongson 3C5000 microprocessor chip to process and analyze the data collected by the monitoring module 12 in real time, and not only has the data storage function (it can store the monitoring data within a certain period of time for subsequent query and analysis of the cause of the fault), but also can judge the monitoring data according to the preset algorithm and threshold value and automatically trigger the alarm signal when the data is abnormal to transmit the fault information to the communication module; the communication module adopts the low-power, high-speed GC080X wireless communication chip, which can transmit the alarm information and monitoring data generated by the data processing module to the remote monitoring center (supporting a variety of wireless communication protocols, such as Wi-Fi, Bluetooth, ZigBee and 4G / 5G, etc., which can be flexibly selected according to the actual application scenario and communication distance requirements), so that the maintenance personnel can remotely monitor the operation status of the communication cable in real time through wireless communication technology, timely grasp the health status of the communication cable and respond at the first time when the fault occurs, greatly improving the maintenance efficiency and reliability of the communication network.

[0022] The flame retardant structure is a composite filler 13 of magnesium hydroxide and cross-linked polyethylene filled in the gaps of the cable core, and the filling coefficient is controlled at 0.90-0.95; wherein, magnesium hydroxide can decompose and absorb a large amount of heat and release moisture at high temperature, thereby playing a role of flame retardancy and cooling; cross-linked polyethylene provides good flexibility and structural stability for the filling layer; in addition, the filling coefficient of the composite filler 13 of magnesium hydroxide and cross-linked polyethylene is controlled at 0.90-0.95, which not only allows the gaps between the core wires to be fully filled, but also does not cause excessive impact on the overall flexibility of the communication cable, while ensuring that when a fire occurs, the flame can be effectively prevented from spreading longitudinally.

[0023] The water-blocking structure is composed of an expandable water-blocking grease 11 filled in the gap of the cable core and a first water-blocking tape 1 and a second water-blocking tape 3 sequentially arranged outside the cable core. The first water-blocking tape 1 and the second water-blocking tape 3 are composite films of a water-absorbing and expanding film and a waterproof film. The expandable water-blocking grease 11 is a mixed grease of a water-absorbing and expanding material and a basic waterproof grease. The first water-blocking tape 1 and the second water-blocking tape 3 are separated by a polyethylene insulation layer 2. The water-absorbing and expanding film can be a water-absorbing and expanding resin film, and the water-absorbing and expanding material can be a water-absorbing and expanding resin powder. For the portion outside the cable core, the present invention wraps the overlapping layers of the composite films. The isolated double-layer water-blocking composite tape can not only use the waterproof film for long-term sealing and waterproofing, but also provide preliminary blocking through the water-absorbing and swelling film when water flows in; for the inside of the cable core, the highly absorbent resin in the swelling water-blocking paste 11 can quickly absorb water and expand the volume, thereby filling up the excess gaps, and together with the basic waterproof paste, form a tight and continuous waterproof barrier to prevent water from further penetrating inward (even under a certain water pressure, this barrier can effectively prevent the flow of water, thereby protecting the key components of the communication line group 10 and the intelligent monitoring unit inside the cable core from water erosion, ultimately ensuring the normal communication function of the communication cable).

[0024] The shielding structure is composed of an alloy aluminum sheath 4 and a high magnetic permeability steel belt 7 which are sequentially sleeved or wrapped outside the second water-blocking tape 3 from the inside to the outside. The thickness of the alloy aluminum sheath 4 is 1.5-2.5 mm (such as seamless welding using an alloy aluminum plate with a thickness of 1.9 mm), and the thickness of the high magnetic permeability steel belt 7 is 0.3-0.8 mm (such as gap wrapping using a high magnetic permeability steel belt 7 with a thickness of 0.52 mm), and the wrapping gap does not exceed 25%; in addition, the cable shielding coefficient does not exceed 0.008; this double-layer shielding design can effectively shield external electromagnetic interference and ensure the purity and stability of the internal signal transmission of the communication cable (especially during long-distance transmission, it can reduce the occurrence of signal attenuation and distortion).

[0025] The alloy aluminum sheath 4 and the high magnetic permeability steel belt 7 are separated by an insulating lining layer 5; by using the insulating lining layer 5 to isolate the two shielding layers, not only can short circuits between layers be prevented, but it can also play a certain buffering role and improve the mechanical properties of the communication cable.

[0026] The oxygen-isolating structure is composed of a first oxygen-isolating tape 6 wrapped around the insulating lining layer 5 and a second oxygen-isolating tape 8 wrapped around the high-magnetic steel tape 7. The first oxygen-isolating tape 6 and the second oxygen-isolating tape 8 are both low-smoke halogen-free glass fiber tapes with an oxygen index of >50 and a wrapping overlap rate of >25%. When the cable is attacked by flames, the oxygen-isolating structure can, on the one hand, prevent oxygen from penetrating into the interior, protect the internal core wire, and avoid damage due to burning, thereby ensuring that the communication cable can still maintain basic functions for a certain period of time in the event of a fire, and provide protection for the normal operation of important equipment such as fire alarm systems and emergency lighting systems. On the other hand, it can also effectively prevent the risk of the basic waterproof grease dripping and catching fire when it encounters heat or fire.

[0027] The outer sheath 9 is a highly flame-retardant, low-smoke, halogen-free polyolefin sheath with an oxygen index > 36 and is extruded and coated outside the second oxygen-isolating tape 8. The thickness of the outer sheath 9 is controlled at 2.0-2.1 mm, and the surface of the outer sheath 9 is also provided with an anti-slip texture; wherein the anti-slip texture can increase the friction of the communication cable during the laying and use process, and prevent the communication cable from slipping; in addition, the highly flame-retardant, low-smoke, halogen-free polyolefin sheath also has good UV resistance, and can maintain its physical properties and appearance integrity under long-term outdoor exposure, thereby effectively extending the service life of the cable.

[0028] The above embodiments are intended to illustrate the present invention, not to limit the present invention. Any solution that is a simple transformation of the present invention belongs to the protection scope of the present invention.

Claims

1. Intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable, characterized by: The invention comprises a communication line group (10), an intelligent monitoring unit, a flame retardant structure, a water blocking structure, a shielding structure, an oxygen isolation structure and an outer sheath (9), wherein a plurality of the intelligent monitoring units are evenly distributed along the length direction of the communication line group (10) and together with the communication line group (10) form a cable core, the flame retardant structure, the water blocking structure, the shielding structure and the flame retardant oxygen isolation structure are all arranged between the cable core and the outer sheath (9), the intelligent monitoring unit comprises a monitoring module (12), a data processing module and a communication module, the monitoring module (12) is jointly composed of a temperature sensor, a humidity sensor, a strain sensor and a current monitor, the data processing module is electrically connected to the monitoring module (12) on the one hand and communicates with a remote monitoring center through the communication module on the other hand.

2. The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable according to claim 1 is characterized in that: The communication line group (10) is formed by twisting a plurality of communication wires in groups, wherein the communication wires have a conductor (101) drawn from high-precision oxygen-free copper wire and having a diameter in the range of 0.902 to 0.905 mm, and a skin-foam-skin physical foamed polyolefin insulation sleeve (102) extruded and wrapped around the conductor (101), wherein the thickness of the inner skin layer of the skin-foam-skin physical foamed polyolefin insulation sleeve (102) is controlled at 0.15±0.01 mm, the foaming degree of the foaming layer is controlled at 68±2%, and the thickness of the outer skin layer is controlled at 0.25±0.01 mm.

3. The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable according to claim 1 is characterized in that: The setting interval of the intelligent monitoring units is controlled at 10 to 30 m, the temperature sensor adopts a thermistor sensor, the humidity sensor adopts a capacitive humidity sensor, the strain sensor adopts a fiber grating strain sensor, the current monitor adopts a current transformer, the data processing module adopts a Loongson 3C5000 microprocessor chip, and the communication module adopts a GC080X wireless communication chip.

4. The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable according to claim 1, characterized in that: The flame retardant structure is a composite filler (13) of magnesium hydroxide and cross-linked polyethylene filled in the gaps of the cable core, and the filling coefficient is controlled at 0.90-0.

95.

5. The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable according to claim 1, characterized in that: The water-blocking structure is composed of an expandable water-blocking grease (11) filled in the gap of the cable core, and a first water-blocking tape (1) and a second water-blocking tape (3) sequentially arranged outside the cable core, wherein the first water-blocking tape (1) and the second water-blocking tape (3) are both composite films of a water-absorbing and expanding film and a waterproof film, and the expandable water-blocking grease (11) is a mixed grease of a water-absorbing and expanding material and a basic waterproof grease.

6. The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable according to claim 5, characterized in that: The first water-blocking tape (1) and the second water-blocking tape (3) are separated by a polyethylene heat-insulating layer (2).

7. The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable according to claim 6, characterized in that: The shielding structure is composed of an alloy aluminum sheath (4) and a high-magnetic-conductivity steel belt (7) which are sequentially sleeved or wrapped around the second water-blocking belt (3) from the inside to the outside, the thickness of the alloy aluminum sheath (4) is 1.5 to 2.5 mm, the thickness of the high-magnetic-conductivity steel belt (7) is 0.3 to 0.8 mm, and the wrapping gap does not exceed 25%.

8. The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable according to claim 7, characterized in that: The alloy aluminum sheath (4) and the high magnetic permeability steel strip (7) are separated by an insulating lining layer (5).

9. The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable according to claim 8, characterized in that: The oxygen-isolating structure is composed of a first oxygen-isolating tape (6) wrapped around the insulating lining layer (5) and a second oxygen-isolating tape (8) wrapped around the high-magnetic-conductivity steel tape (7), wherein the first oxygen-isolating tape (6) and the second oxygen-isolating tape (8) are both low-smoke halogen-free glass fiber tapes with an oxygen index of >50 and a wrapping overlap rate of >25%.

10. The intelligent monitoring highly flame-retardant and water-resistant long-distance symmetrical communication cable according to claim 9, characterized in that: The outer sheath (9) is a highly flame-retardant, low-smoke, halogen-free polyolefin sheath with an oxygen index of >36 and is extruded and coated outside the second oxygen-isolating tape (8). The thickness of the outer sheath (9) is controlled to be 2.0 to 2.1 mm, and the surface of the outer sheath (9) is also provided with an anti-slip texture.

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