A cable with high breakage-sensitive feedback degree and a problem feedback method

Abstract

The application belongs to the technical field of cables, and particularly relates to a cable with high damage-sensitive feedback degree and a problem feedback method. The cable with high damage-sensitive feedback degree comprises a cable core, an insulation layer, a fireproof layer and an armored layer arranged in sequence from inside to outside. A monitoring layer is additionally arranged between the insulation layer and the fireproof layer. The monitoring layer is composed of resistance wires. Two ends of the resistance wires are connected with a monitor. The monitor feeds back the damage state of the cable by means of the resistance value change of the monitoring layer. The monitoring layer composed of the resistance wires is additionally arranged between the insulation layer and the fireproof layer. When the cable is damaged by external factors, the resistance wires will be broken before the insulation layer, and the resistance value will change immediately. The monitor can capture the abnormality in real time and give a warning. The cable can be maintained in time before the cable core is damaged.

Description

Technical Field

[0001] This invention belongs to the field of cable technology, specifically relating to a cable with high damage sensitivity and a problem feedback method. Background Technology

[0002] During long-term service, cables are subjected to multiple factors such as soil compression, puncture from external construction, rodent and ant damage, and environmental corrosion, gradually leading to insulation layer damage and even internal core damage. If these issues are not detected and addressed in time, they can easily cause accidents such as leakage short circuits, power outages, and signal transmission failures. In severe cases, they may even pose safety risks such as fires and electric shocks, creating potential safety hazards.

[0003] The mainstream methods for detecting cable damage currently rely on post-incident investigation and regular inspections. However, both of these methods are lagging and cannot achieve real-time online monitoring and early warning of damage during operation, making it difficult to achieve proactive maintenance.

[0004] To achieve online monitoring of cable status, some solutions attempt to integrate sensing elements into the cable structure, such as using built-in optical fibers for distributed temperature or strain monitoring. However, fiber optic sensing systems require expensive optical demodulation equipment, have complex installation processes, and are limited in applications with strong electromagnetic interference or harsh construction environments. Furthermore, optical fibers themselves are relatively brittle, which is not conducive to the bending and laying of cables.

[0005] Therefore, the existing technology lacks a cable structure and feedback method that can provide real-time feedback on the damage status during operation. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a cable with high damage sensitivity and a problem feedback method. By adding a monitoring layer composed of resistance wires between the insulation layer and the fireproof layer, when the cable is damaged by external forces, the resistance wires will break before the insulation layer, causing an immediate change in the resistance value. The monitor can capture the anomaly in real time and issue an early warning, thus maintaining the cable in time before the cable core is damaged.

[0007] The specific technical solution adopted in this invention is as follows:

[0008] A cable with high damage sensitivity feedback includes, from the inside out, a cable core, an insulation layer, a fireproof layer, and an armor layer. A monitoring layer is also provided between the insulation layer and the fireproof layer. The monitoring layer is composed of resistance wires, and the two ends of the resistance wires are respectively connected to a monitor. The monitor uses the change in the resistance value of the monitoring layer to provide feedback on the damage status of the cable.

[0009] The resistance wire includes a first resistance wire and a second resistance wire arranged in an X-shape. The first resistance wire and the second resistance wire are electrically connected at the intersection. The monitoring layer forms a mesh structure with the help of the first resistance wire and the second resistance wire.

[0010] The first end of the first resistance wire is short-circuited with the first end of the second resistance wire to form a first end lead electrode, and the last end of the first resistance wire is short-circuited with the last end of the second resistance wire to form a last end lead electrode. The monitoring layer is provided with multiple sets on the cable, and the first end lead electrode and the last end lead electrode of each set of monitoring layers are respectively connected to a set of monitors.

[0011] Both the first resistance wire and the second resistance wire are spirally wound along the axial direction of the cable. The spiral angle of the first resistance wire is 10-15°, the spiral angle of the second resistance wire is 10-15°, and the winding direction of the second resistance wire is opposite to that of the first resistance wire.

[0012] The first resistance wire and the second resistance wire are wound alternately to form a shape, and the second resistance wire is wound around the first resistance wire at least once at the intersection.

[0013] The resistance wire comprises, from the inside out, a fiber layer, a bonding layer, a resistive functional layer, and an insulating varnish layer. The fiber layer is poly(p-phenylene terephthalamide); the bonding layer is a nickel-phosphorus alloy with nickel as the base and a phosphorus content of 5-12 wt%; the resistive functional layer is a nickel-chromium alloy with nickel as the base, a chromium content of 20.0-23.0 wt%, a silicon content of 0.75-1.60 wt%, and a carbon content of 0.05-0.08 wt%; and the insulating varnish layer is any one of polyurethane insulating varnish, polyesterimide insulating varnish, or polyamide-imide insulating varnish.

[0014] The fiber layer has a diameter of 0.08-0.1 mm, the bonding layer has a thickness of 1-2 μm, the resistive functional layer has a thickness of 8-10 μm, and the insulating varnish layer has a thickness of 2-4 μm.

[0015] A problem feedback method for cables with high damage sensitivity includes the following steps:

[0016] S1. During cable operation, the real-time resistance values ​​at both ends of the monitoring layer are collected in real time.

[0017] S2. Compare the real-time resistance value with the preset reference resistance value and calculate the resistance change rate.

[0018] S3. When the rate of change of resistance reaches the preset damage judgment threshold, a damage warning signal is generated and a cable maintenance prompt is output.

[0019] The damage determination threshold specifically includes:

[0020] S301. When the resistance change rate is ≥1% and <3%, it is judged as minor damage and a level 1 warning is generated.

[0021] S302. When the resistance change rate is ≥3% and <10%, it is judged as moderate damage and a level 2 warning is generated.

[0022] S303. When the resistance change rate is ≥10%, it is judged as severely damaged, and a level 3 warning is generated.

[0023] The beneficial effects of this invention are:

[0024] 1. This invention adds a monitoring layer composed of resistance wires between the insulation layer and the fireproof layer. When external punctures, corrosion, or compression penetrate the outer structure and damage the monitoring layer, the breakage of the resistance wire will cause an immediate change in the resistance value. The monitor can capture the anomaly in real time and issue an early warning, transforming the traditional passive repair mode of post-event investigation and regular inspection into proactive operation and maintenance. It can maintain the cable in time before the insulation layer and cable core are damaged, thereby solving the problem of the lag in cable detection.

[0025] 2. The monitoring layer in this invention is formed by a cross-mesh structure of a first resistance wire and a second resistance wire. Regardless of whether the damage is a longitudinal cut, a transverse cut, or a point puncture, at least one current path will be cut off, eliminating the detection blind zone. In addition, the mesh structure of the monitoring layer not only serves a monitoring function but also acts as a reinforcing layer, which can disperse local impact stress, prevent the outer layer crack from expanding inward, and improve the overall structural strength of the cable. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the cross-sectional structure of the cable;

[0027] Figure 2 This is a schematic diagram of the monitoring layer structure;

[0028] In the attached diagram, 1 is the cable core, 2 is the insulation layer, 3 is the fireproof layer, 4 is the armor layer, 5 is the monitoring layer, 501 is the first resistance wire, 502 is the second resistance wire, and 6 is the monitor. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0030] Specific embodiments, such as Figure 1-2 As shown, the present invention provides a cable with high damage sensitivity feedback, comprising a cable core 1, an insulation layer 2, a fireproof layer 3 and an armor layer 4 arranged sequentially from the inside out. A monitoring layer 5 is further provided between the insulation layer 2 and the fireproof layer 3. The monitoring layer 5 is composed of resistance wires, and the two ends of the resistance wires are respectively connected to a monitor 6. The monitor 6 uses the change in the resistance value of the monitoring layer 5 to provide feedback on the damage status of the cable.

[0031] This invention adds a monitoring layer 5 composed of resistance wires between the insulation layer 2 and the fireproof layer 3. When external damage penetrates the armor layer 4 and the fireproof layer 3 and damages the monitoring layer 5, the resistance wires will break locally or deform in cross-section before the insulation layer 2, causing the resistance value to rise. The monitor 6 can continuously collect this resistance value, and can detect the abnormality and issue an early warning at the first moment of damage, transforming passive emergency repair into proactive maintenance. Before the insulation layer 2 and the cable core 1 are damaged, the cable can be maintained in time, thereby solving the problem of the lag in cable detection.

[0032] like Figure 2 As shown, the resistance wire includes a first resistance wire 501 and a second resistance wire 502 arranged in an X-shape. The first resistance wire 501 and the second resistance wire 502 are electrically connected at the intersection. The monitoring layer 5 forms a mesh structure with the help of the first resistance wire 501 and the second resistance wire 502.

[0033] Parallel resistance wires are only sensitive to longitudinal cracks. When a thin transverse crack appears, it may penetrate directly through the gaps between the parallel resistance wires and damage the cable core 1. In contrast, the monitoring layer 5 of this invention, formed by the first resistance wire 501 and the second resistance wire 502, creates a cross-mesh structure. Regardless of whether the damage is a longitudinal cut, a transverse cut, or a point puncture, it will cut off at least one current path, eliminating detection blind spots. Simultaneously, the mesh structure of the monitoring layer 5 not only serves a monitoring function but also acts as a reinforcing layer, dispersing local impact stress, preventing outer cracks from expanding inward, and improving the overall structural strength of the cable.

[0034] In addition, there are blank areas near the first and last lead-out electrodes that cannot be covered by the resistance wire. These blank areas can be filled with other filler materials, such as polypropylene filler rope, which can protect the insulation layer 2 and also fix the resistance wire.

[0035] Figure 2 This is a schematic diagram of the structure. The mesh gap has been enlarged to facilitate observation of the winding method. In practical applications, the mesh aperture size can be controlled by adjusting the winding density.

[0036] The first end of the first resistance wire 501 is short-circuited with the first end of the second resistance wire 502 to form a first end lead electrode, and the last end of the first resistance wire 501 is short-circuited with the last end of the second resistance wire 502 to form a last end lead electrode. The monitoring layer 5 is provided with multiple sets on the cable, and the first end lead electrode and the last end lead electrode of each set of monitoring layers 5 are respectively connected to a set of monitors 6.

[0037] Among them, the first and last lead-out electrodes pass through the armor layer 4 and the fireproof layer 3 through the insulating and sealed terminals, and are connected to the resistance acquisition terminal of the monitor.

[0038] When monitoring layer 5 is damaged, the resistance wire experiences localized reduction in cross-sectional area or breakage, reducing the effective conductive cross-sectional area of ​​the parallel path. Consequently, the total resistance increases accordingly. Monitor 6 can identify the overall damage state of monitoring layer 5 by collecting the resistance values ​​at both ends. Furthermore, this invention features multiple sets of monitoring layers 5, each with an independent monitoring circuit. This allows operators to directly pinpoint the damaged cable section using monitor 6, and ensures that abnormal resistance values ​​or monitor 6 malfunctions in a single section do not affect the normal monitoring function of other sections.

[0039] like Figure 2 As shown, both the first resistance wire 501 and the second resistance wire 502 are spirally wound along the axial direction of the cable. The spiral angle of the first resistance wire 501 is 10-15°, the spiral angle of the second resistance wire 502 is 10-15°, and the winding direction of the second resistance wire 502 is opposite to that of the first resistance wire 501.

[0040] The reverse spiral winding of the first resistance wire 501 and the second resistance wire 502 can form a uniformly intersecting grid on the entire circumference of the cable, achieving full circumferential coverage of the cable core 1 and reducing monitoring blind spots. At the same time, the spirally arranged resistance wires have axial deformation margin. When the cable is bent during laying, reeling, or thermal expansion and contraction due to temperature, the spiral first resistance wire 501 and the second resistance wire 502 can adaptively adjust and release tensile stress, avoiding resistance wire breakage caused by hard stretching during straight laying. In addition, the spiral structure can bear part of the axial tensile force, thereby improving the overall tensile strength of the cable.

[0041] like Figure 2 As shown, the first resistance wire 501 and the second resistance wire 502 are alternately wound into shape, and the second resistance wire 502 wraps around the first resistance wire 501 at least once at the intersection.

[0042] Compared to the cross-point connection methods of spot welding and conductive adhesive bonding, the interlocking node structure has a larger contact area, and the mechanically clamped structure can maintain a tight contact during long-term operation, avoiding the failure of the electrical connection between the first resistance wire 501 and the second resistance wire 502 due to desoldering and adhesive aging and peeling, thereby reducing the probability of false alarms and missed alarms of the monitor 6.

[0043] Meanwhile, the interlocking nodes lock the two resistance wires together into a continuous overall mesh skeleton. Local external forces can be transmitted through the nodes throughout the mesh structure, resulting in better stress dispersion and further improving the cable's damage prevention and impact resistance. Moreover, this structure can be formed in one step by CNC winding equipment, eliminating the need for subsequent point-by-point processing and significantly improving production efficiency.

[0044] The resistance wire comprises, from the inside out, a fiber layer, a bonding layer, a resistive functional layer, and an insulating varnish layer. The fiber layer is poly(p-phenylene terephthalamide); the bonding layer is a nickel-phosphorus alloy with nickel as the base and a phosphorus content of 5-12 wt%; the resistive functional layer is a nickel-chromium alloy with nickel as the base, a chromium content of 20.0-23.0 wt%, a silicon content of 0.75-1.60 wt%, and a carbon content of 0.05-0.08 wt%; and the insulating varnish layer is any one of polyurethane insulating varnish, polyesterimide insulating varnish, or polyamide-imide insulating varnish.

[0045] The resistance wire in this invention adopts a four-layer composite structure. The inner layer of poly(p-phenylene terephthalamide) fiber serves as a mechanical skeleton, possessing high tensile strength and bearing the vast majority of tensile and bending loads. The nickel-phosphorus alloy bonding layer can form a substrate on the surface of the insulating fiber, buffering the difference in thermal expansion and contraction between the fiber and the metal layer, and preventing the coating from peeling off or cracking. The nickel-chromium alloy resistive functional layer has stable resistivity and a small temperature coefficient, ensuring detection accuracy and long-term stability. The outermost insulating varnish layer ensures electrical insulation at non-intersection locations.

[0046] In this process, the insulating varnish layer of the resistance wire is stripped at equal intervals in advance, that is, at the intersection point, to ensure that the resistive functional layers of the first resistance wire 501 and the second resistance wire 502 can directly contact and form an electrical connection at the intersection point.

[0047] The fiber layer has a diameter of 0.08-0.1 mm, the bonding layer has a thickness of 1-2 μm, the resistive functional layer has a thickness of 8-10 μm, and the insulating varnish layer has a thickness of 2-4 μm.

[0048] A problem feedback method for cables with high damage sensitivity includes the following steps:

[0049] S1. During cable operation, the real-time resistance values ​​at both ends of monitoring layer 5 are collected in real time.

[0050] S2. Compare the real-time resistance value with the preset reference resistance value and calculate the resistance change rate.

[0051] S3. When the rate of change of resistance reaches the preset damage judgment threshold, a damage warning signal is generated and a cable maintenance prompt is output.

[0052] The damage determination threshold specifically includes:

[0053] S301. When the resistance change rate is ≥1% and <3%, it is judged as minor damage and a level 1 warning is generated.

[0054] S302. When the resistance change rate is ≥3% and <10%, it is judged as moderate damage and a level 2 warning is generated.

[0055] S303. When the resistance change rate is ≥10%, it is judged as severely damaged, and a level 3 warning is generated.

[0056] This invention sets three damage judgment thresholds, corresponding to three damage levels: minor, moderate, and severe. The resistance change rate is calculated as: (real-time resistance value - reference resistance value) / reference resistance value × 100%. The reference resistance value is the initial resistance value of monitoring layer 5 collected after cable installation and under normal operating temperature, which can be corrected for temperature changes based on ambient temperature.

[0057] When the resistance value fluctuates slightly by 1%-3%, the resistance wire of monitoring layer 5 only undergoes elastic deformation or slight cross-sectional shrinkage, and may not yet show structural fracture. At this time, a level one warning is generated, prompting maintenance personnel to conduct routine inspections of the warning section, check for potential external compression or scraping hazards, and perform non-destructive testing on site. If a small but deep crack is found, which has damaged insulation layer 2 or cable core 1, timely maintenance should be carried out.

[0058] When the resistance value fluctuates within a moderate range of 3%-10%, a single resistance wire in monitoring layer 5 may experience a local breakage or a continuous reduction in the cross-section of multiple resistance wires, resulting in a significant decrease in the effective conductive cross-sectional area. At this time, a level 2 warning is generated, prompting maintenance personnel to develop a targeted repair plan and complete the repair of the damaged point within the specified window period to prevent the damage from further expanding to cable core 1.

[0059] When the resistance value fluctuates significantly by more than 10%, multiple resistance wires in monitoring layer 5 break simultaneously and multiple monitoring channels fail, indicating that the cable has suffered sudden external force damage. At this time, a level 3 warning is generated, requiring maintenance personnel to rush to the scene immediately to handle the situation and replace the damaged cable section to prevent accidents from occurring.

[0060] In addition, the present invention sets a trigger threshold of 1%, which can filter out the slight deviation in resistance value caused by ambient temperature fluctuations, thermal expansion and contraction of the cable itself, and bending deformation during normal operation of the cable, thereby reducing the probability of false alarms caused by environmental interference and normal operating conditions, and improving the operational stability and reliability of the entire monitoring system.

Claims

1. A cable with high damage sensitivity feedback, comprising, from the inside out, a cable core (1), an insulation layer (2), a fireproof layer (3), and an armor layer (4), characterized in that, A monitoring layer (5) is added between the insulation layer (2) and the fireproof layer (3). The monitoring layer is composed of resistance wires, and the two ends of the resistance wires are connected to the monitor (6). The monitor (6) uses the change in the resistance value of the monitoring layer (5) to provide feedback on the damage status of the cable.

2. The cable with high breakage sensitivity feedback according to claim 1, characterized in that, The resistance wire includes a first resistance wire (501) and a second resistance wire (502) arranged in an X-shape. The first resistance wire (501) and the second resistance wire (502) are electrically connected at the intersection. The monitoring layer forms a mesh structure with the help of the first resistance wire (501) and the second resistance wire (502).

3. The cable with high breakage sensitivity feedback according to claim 2, characterized in that, The first end of the first resistance wire (501) is short-circuited with the first end of the second resistance wire (502) to form a first end lead electrode. The tail end of the first resistance wire (501) is short-circuited with the tail end of the second resistance wire (502) to form a tail end lead electrode. The monitoring layer (5) is provided with multiple sets on the cable. The first end lead electrode and the tail end lead electrode of each monitoring layer (5) are respectively connected to a set of monitors (6).

4. The cable with high breakage sensitivity feedback according to claim 2, characterized in that, Both the first resistance wire (501) and the second resistance wire (502) are spirally wound along the axial direction of the cable. The spiral angle of the first resistance wire (501) is 10-15°, the spiral angle of the second resistance wire (502) is 10-15°, and the winding direction of the second resistance wire (502) is opposite to that of the first resistance wire (501).

5. A cable with high breakage sensitivity feedback according to claim 2, characterized in that, The first resistance wire (501) and the second resistance wire (502) are alternately wound and formed, and the second resistance wire (502) is wound around the first resistance wire (501) at least once at the intersection.

6. The cable with high breakage sensitivity feedback according to claim 1, characterized in that, The resistance wire comprises, from the inside out, a fiber layer, a bonding layer, a resistive functional layer, and an insulating varnish layer. The fiber layer is poly(p-phenylene terephthalamide); the bonding layer is a nickel-phosphorus alloy with nickel as the base and a phosphorus content of 5-12 wt%; the resistive functional layer is a nickel-chromium alloy with nickel as the base, a chromium content of 20.0-23.0 wt%, a silicon content of 0.75-1.60 wt%, and a carbon content of 0.05-0.08 wt%; and the insulating varnish layer is any one of polyurethane insulating varnish, polyesterimide insulating varnish, or polyamide-imide insulating varnish.

7. The cable with high breakage sensitivity feedback according to claim 6, characterized in that, The fiber layer has a diameter of 0.08-0.1 mm, the bonding layer has a thickness of 1-2 μm, the resistive functional layer has a thickness of 8-10 μm, and the insulating varnish layer has a thickness of 2-4 μm.

8. A problem feedback method for a cable with high damage sensitivity, used to provide damage status feedback for the cable with high damage sensitivity as described in claim 1, characterized in that, The cable problem feedback method specifically includes the following steps: S1. During cable operation, the real-time resistance values ​​at both ends of the monitoring layer are collected in real time. S2. Compare the real-time resistance value with the preset reference resistance value and calculate the resistance change rate. S3. When the rate of change of resistance reaches the preset damage judgment threshold, a damage warning signal is generated and a cable maintenance prompt is output.

9. A problem feedback method for cables with high damage sensitivity according to claim 8, characterized in that, The damage determination threshold specifically includes: S301. When the resistance change rate is ≥1% and <3%, it is judged as minor damage and a level 1 warning is generated. S302. When the resistance change rate is ≥3% and <10%, it is judged as moderate damage and a level 2 warning is generated. S303. When the resistance change rate is ≥10%, it is judged as severely damaged, and a level 3 warning is generated.

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