Cable detection device and method

Abstract

The present invention provides a cable detection device and method thereof, wherein the cable detection device includes a shell, a conveying component, a heating component and a liquid preheater, wherein a heating zone and a liquid storage tank are formed in the shell; the conveying component is arranged in the shell, and the conveying component is used to convey the cable from the heating zone to the liquid storage tank; the heating component is arranged in the heating zone, and the heating component is used to heat the cable in the heating zone to a first preset temperature, and the first preset temperature is less than the maximum tolerance temperature of the cable; the liquid preheater is arranged in the liquid storage tank, and the liquid preheater contacts the conductive liquid in the liquid storage tank, and is used to heat the conductive liquid to a second preset temperature; the value of the first preset temperature is the same as the value of the second preset temperature. The technical solution of the present invention facilitates the conductive liquid to enter the damaged area of ​​the cable.

Description

Technical Field

[0001] The present invention relates to the technical field of cable detection, and in particular to a cable detection device and a method thereof. Background Art

[0002] Cables play a vital role in various infrastructures of modern society. They are used in power transmission, communication systems, data processing facilities and other fields. The structure of cables usually includes the core conductive part and the outer insulation layer. Their integrity is crucial to ensure the reliable operation and overall safety of the system. Therefore, accurate cable integrity testing has become an important part of maintenance work.

[0003] In traditional cable testing methods, the cable is usually immersed in a conductive liquid to test whether it has defects. By running electricity through the cable and testing whether the surrounding liquid is charged, the insulation performance of the cable and whether the outer sheath is damaged can be determined. However, this method has certain limitations when dealing with minor damage. When the damage to the cable is small and insufficient for the liquid to penetrate naturally, the test results may be inaccurate.

[0004] In order to improve the accuracy of detection, some detection systems have introduced a booster component to increase the pressure of the conductive liquid so that it can quickly enter the tiny cracks or damage inside the cable. However, this boost may have an adverse effect on the flexible outer skin of the cable. Under the action of pressure, the flexible outer skin of the cable may be further compressed, which will in turn enhance the sealing effect of the damaged area, making it more difficult for the conductive liquid to enter the damaged area, thereby affecting the accuracy of the detection results. Therefore, a solution that can effectively identify and evaluate cable damage is needed. Summary of the invention

[0005] The main purpose of the present invention is to solve the technical problem that it is difficult for the detection method in the prior art to allow the conductive liquid to enter the damaged area of ​​the cable.

[0006] A first aspect of the present invention provides a cable detection device, comprising a shell, a conveying component, a heating component and a liquid preheater, wherein a heating zone and a liquid storage tank are formed in the shell; the conveying component is arranged in the shell, and the conveying component is used to convey the cable from the heating zone to the liquid storage tank; the heating component is arranged in the heating zone, and the heating component is used to heat the cable in the heating zone to a first preset temperature, and the first preset temperature is lower than the maximum tolerable temperature of the cable; the liquid preheater is arranged in the liquid storage tank, and the liquid preheater contacts with the conductive liquid in the liquid storage tank, and is used to heat the conductive liquid to a second preset temperature; the value of the first preset temperature is the same as the value of the second preset temperature.

[0007] Optionally, the heating assembly includes a cylinder and a heating element disposed on the cylinder, a cylinder cavity is formed in the cylinder, two opposite ends of the cylinder are respectively formed with a cable inlet and a cable outlet connected to the cylinder cavity, and the cable outlet is arranged relative to the cable inlet and close to the liquid storage tank;

[0008] The heating element is used to heat the barrel cavity to the first preset temperature, and the cables in the heating zone are arranged to pass through the cable inlet, the barrel cavity and the cable outlet in sequence.

[0009] Optionally, the heating element extends spirally on the outer peripheral wall of the cylinder.

[0010] Optionally, the conveying assembly includes two guide wheels located at opposite ends of the cylinder, and each of the guide wheels is used to support the cable so that the cable does not contact the peripheral wall of the cylinder.

[0011] A second aspect of the present invention provides a cable detection method, comprising:

[0012] Determining a first preset temperature suitable for the type of cable to be tested;

[0013] Setting the operating temperature of the heating component to the first preset temperature;

[0014] heating the conductive liquid in the liquid storage tank to a second preset temperature equal to the first preset temperature by a liquid preheater;

[0015] Move the cable into the heating zone by means of a conveying assembly, and when the surface temperature of the cable reaches the first preset temperature, move the cable into the liquid storage tank;

[0016] Collect and analyze data obtained by soaking the cable and conduct a comprehensive assessment of the cable's insulation and integrity.

[0017] Optionally, the first preset temperature is calculated by the following formula:

[0018] ;

[0019] in, is the first preset temperature in Kelvin (K), is the ambient temperature in Kelvin (K), Safety temperature rise, in Kelvin (K), is the heat loss coefficient in watts per square meter Kelvin (W / m²·K), A is the surface area of ​​the cable in square meters (m²), t is the heating time in seconds (s), m is the mass of the cable in kilograms (kg), is the specific heat capacity of the cable material, expressed in joules per kilogram Kelvin (J / kg·K); exp is the exponential function of the base of the natural logarithm.

[0020] Optionally, heating the conductive liquid in the liquid storage tank to a second preset temperature equal to the first preset temperature by a liquid preheater comprises:

[0021] Select saline solution as the conductive solution;

[0022] adjusting the mass ratio of salt to water in the salt water solution according to the first preset temperature;

[0023] The saline solution is heated using a liquid preheater to a second preset temperature equal to the first preset temperature.

[0024] Optionally, the mass ratio of salt to water in the saline solution is adjusted according to the first preset temperature and is calculated by the following formula:

[0025] ;

[0026] in, The first preset temperature The solubility under is the reference temperature The solubility under is the enthalpy change during the dissolution process, in joules per mole (J / mol), R is the ideal gas constant, which is 8.314 J / mol·K, is the reference temperature in Kelvin (K), is the first preset temperature, in Kelvin (K).

[0027] The cable detection device of the present invention has the following advantages:

[0028] By setting an appropriate first preset temperature, the heating component can accurately control the temperature of the cable, so that the flexible outer skin of the cable expands when heated. This thermal expansion phenomenon causes the originally tiny and difficult to observe cracks or damaged parts inside the cable to be physically expanded, making these cracks or damaged parts more easily accessible to conductive liquids. Normally, if the cable is not properly heated, these tiny defects may prevent the entry of conductive liquids because their openings are too small, which will make the detection results inaccurate or miss the real damage. By accurately controlling the heating, it can be ensured that each potential damage point is fully exposed, thereby increasing the sensitivity and accuracy of the detection.

[0029] In addition, heating the conductive liquid to the same second preset temperature as the cable is also for the purpose of improving detection efficiency and accuracy. First, heating the conductive liquid to the same temperature as the heated cable can prevent the cable material from shrinking rapidly due to the temperature difference. This shrinkage phenomenon may cause the cracks after thermal expansion to close rapidly, thereby hindering the penetration of the conductive liquid. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0031] Figure 1 It is a structural schematic diagram of an embodiment of a cable detection device of the present invention;

[0032] Figure 2 for Figure 1 A cross-sectional view of

[0033] Figure 3 FIG. 1 is a schematic diagram of an embodiment of a cable detection method in an embodiment of the present invention.

[0034] Description of Figure Numbers:

[0035] 1. Shell; 11. Heating zone; 12. Liquid storage tank; 2. Conveying assembly; 21. Guide wheel; 3. Heating assembly; 31. Cylinder; 311. Cable inlet; 312. Cable outlet; 32. Heating element; 4. Liquid preheater. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] The terms "including" and "having" and any variations thereof mentioned in the embodiments of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device end including a series of steps or units is not limited to the listed steps or units, but may optionally include other steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or device ends.

[0038] To facilitate understanding of this embodiment, a cable detection device disclosed in an embodiment of the present invention is first introduced in detail.

[0039] like Figure 1 to Figure 2 As shown, the cable detection device includes a shell 1, a conveying component 2, a heating component 3 and a liquid preheater, and a heating area 11 and a liquid storage tank 12 are formed in the shell 1; the conveying component 2 is arranged in the shell 1, and the conveying component 2 is used to convey the cable from the heating area 11 to the liquid storage tank 12; the heating component 3 is arranged in the heating area 11, and the heating component 3 is used to heat the cable in the heating area 11 to a first preset temperature, and the first preset temperature is lower than the maximum tolerance temperature of the cable; the liquid preheater 4 is arranged in the liquid storage tank 12, and the liquid preheater 4 is in contact with the conductive liquid in the liquid storage tank 12, and is used to heat the conductive liquid to a second preset temperature; the value of the first preset temperature is the same as the value of the second preset temperature.

[0040] Specifically, the shell 1 is the main structure of the cable detection device, and specific functional areas are designed inside it, such as the heating area 11 and the liquid storage tank 12. The shell 1 provides necessary mechanical support and protection, and also ensures the reasonable layout of the internal components of the device and environmental isolation.

[0041] The conveying component 2 is responsible for conveying the cable from the heating area 11 to the liquid storage tank 12. This component can be a roller (located outside the shell) driven by an electric motor, a roller or other mechanical device suitable for precise position control. The design of the conveying component 2 ensures the smooth movement and accurate positioning of the cable during the heating and immersion process.

[0042] The heating component 3 is arranged in the heating area 11 and is used to heat the cable to a first preset temperature. This component can be a resistance heater, an infrared heater or other efficient heating equipment, etc., which can evenly and accurately control the heating temperature to avoid overheating or uneven temperature of the cable.

[0043] The liquid preheater 4 is located in the liquid storage tank 12, directly in contact with the conductive liquid in the storage tank, and is used to heat the conductive liquid to a second preset temperature. The component can be an immersion heating rod to ensure that the liquid quickly reaches and maintains the required test temperature.

[0044] It can be understood that the cable detection device of the present invention, by setting an appropriate first preset temperature, the heating component 3 can accurately control the temperature of the cable, so that the flexible outer skin of the cable expands when heated. This thermal expansion phenomenon causes the originally tiny and difficult to observe cracks or damaged parts inside the cable to be physically expanded, making these cracks or damaged parts more easily accessible to conductive liquids. Normally, if the cable is not properly heated, these tiny defects may prevent the entry of conductive liquids because their openings are too small, which will make the detection results inaccurate or miss the real damage. By accurately controlling the heating, it can be ensured that each potential damage point is fully exposed, thereby increasing the sensitivity and accuracy of the detection.

[0045] In addition, heating the conductive liquid to the same second preset temperature as the cable is also for the purpose of improving detection efficiency and accuracy. First, heating the conductive liquid to the same temperature as the heated cable can prevent the cable material from shrinking rapidly due to the temperature difference. This shrinkage phenomenon may cause the cracks after thermal expansion to close rapidly, thereby hindering the penetration of the conductive liquid.

[0046] Optionally, the heating assembly 3 includes a barrel 31 and a heating element 32 disposed on the barrel 31, a barrel cavity (not shown) is formed in the barrel 31, and two opposite ends of the barrel 31 are respectively formed with a cable inlet 311 and a cable outlet 312 connected to the barrel cavity, and the cable outlet 312 is arranged relative to the cable inlet 311 and close to the liquid storage tank 12;

[0047] The heating element 32 is used to heat the barrel cavity to a first preset temperature. The cables in the heating zone 11 are arranged in sequence through the cable inlet 311, the barrel cavity and the cable outlet 312.

[0048] Specifically, in this embodiment, the heating element 32 can be a heating coil surrounding the outer wall of the cylinder 31, a heating plate embedded in the wall of the cylinder 31, or other forms of heating technology, which is intended to provide uniform and controllable heating to meet the needs of cable heating.

[0049] The material of the cylinder 31 is selected to be a metal with high thermal conductivity to support rapid and uniform heat conduction.

[0050] It is easy to understand that, based on the structural characteristics of the cylinder 31, the heat in the cylinder cavity is not easy to dissipate, and the cables in the cylinder cavity can be heated evenly, ensuring that all positions of the cable wall can be heated.

[0051] Optionally, the heating element 32 extends in a spiral shape on the outer peripheral wall of the barrel 31. The spiral heating element 32 configuration ensures that the heat energy is evenly distributed around the barrel 31, improves the heating efficiency and the uniformity of the cable heating, and helps to improve the accuracy of the test results. This heating method reduces the loss of heat energy and is more economical and efficient than point or segment heating.

[0052] Optionally, the conveying assembly 2 includes two guide wheels 21 located at opposite ends of the cylinder 31 , and each guide wheel 21 is used to support the cable so that the cable does not contact the peripheral wall of the cylinder 31 .

[0053] Specifically, in this embodiment, the cable and the peripheral wall of the cylinder 31 are not in contact with each other, which means that there is no physical contact between the two.

[0054] By ensuring that the cable does not contact the inner wall of the barrel 31 when heated, the gap in the cable skin is effectively prevented from being accidentally pressed closed after thermal expansion. If this phenomenon occurs, the gap may be resealed after heating, preventing the conductive liquid from entering the defective area inside the cable, thereby affecting the accuracy of the leakage test.

[0055] The present invention also proposes a cable detection method, which is applied to a cable detection device. The specific structure of the cable detection device refers to the above embodiment. Since the cable detection method adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0056] For details, please refer to Figure 3 , the cable detection method includes the following steps:

[0057] S100, determining a first preset temperature suitable for the cable type to be tested;

[0058] Specifically, the first preset temperature is calculated by the following formula:

[0059] .

[0060] in, is the first preset temperature in Kelvin (K), is the ambient temperature in Kelvin (K), Safety temperature rise, in Kelvin (K), is the heat loss coefficient in watts per square meter Kelvin (W / m²·K), A is the surface area of ​​the cable in square meters (m²), t is the heating time in seconds (s), m is the mass of the cable in kilograms (kg), is the specific heat capacity of the cable material, expressed in joules per kilogram Kelvin (J / kg·K); exp is the exponential function of the base of the natural logarithm.

[0061] The following parameters are assumed for the calculation:

[0062] Ambient temperature 293K (20°C), safe temperature rise At 30K, the heat loss coefficient is 10W / m²·K, the surface area A of the cable is 0.1m², the heating time t is 1800 seconds (30 minutes), the mass m of the cable is 1.5kg, and the specific heat capacity of the cable material is 1800J / kg·K;

[0063] Substituting into the formula:

[0064] .

[0065] 311.96K is equal to 38.81°, which means that the preset temperature of the cable heating is about 38.81 degrees Celsius.

[0066] S200, setting the operating temperature of the heating component to the first preset temperature;

[0067] According to the value of the first preset temperature, the control system of the heating component is adjusted, which involves programming or manually setting the temperature control system (including a temperature controller (such as a PID controller)) of the heating component to ensure that the heating component can accurately reach and maintain the required test temperature without exceeding the maximum tolerance temperature of the cable.

[0068] S300, heating the conductive liquid in the liquid storage tank to a second preset temperature equal to the first preset temperature by a liquid preheater;

[0069] The specific steps include:

[0070] S301, selecting a saline solution as a conductive solution;

[0071] Saline solution is selected as the conductive solution mainly because of its simplicity, low cost and good conductivity. Compared with other conductive liquids, such as various metal ion-containing solutions or electrolyte solutions in organic solvents, saline solution has lower preparation and processing requirements and relatively small environmental impact. In addition, the conductivity of the saline solution can be easily adjusted by adjusting the concentration of the salt to adapt it to different test conditions. In addition to saline solution, silver paste, potassium carbonate solution and various acid or alkaline solutions can also be used as conductive solutions, and this application does not limit this.

[0072] S302, adjusting the mass ratio of salt to water in the saline solution according to the first preset temperature;

[0073] Adjusting the mass ratio of salt to water in the saline solution according to the first preset temperature is a key step to ensure test accuracy and solution stability. This step is based on the change in the solubility of salt at different temperatures, and adjusts the salt concentration to adapt to the test temperature to ensure that the solution will not be oversaturated during the heating process, resulting in salt precipitation, or the concentration is too low to affect the conductivity. For example, the solubility of salt generally increases with rising temperature, so a higher salt concentration may be required at high temperatures to maintain the corresponding conductivity. When adjusting this ratio, factors such as solubility, conductivity and thermal stability need to be considered to ensure that the performance of the solution is not affected during the entire test process.

[0074] Specifically, it is calculated by the following formula:

[0075] .

[0076] in, The first preset temperature The solubility under is the reference temperature The solubility under is the enthalpy change during the dissolution process, in joules per mole (J / mol), R is the ideal gas constant, which is 8.314 J / mol·K, is the reference temperature in Kelvin (K), is the first preset temperature, in Kelvin (K).

[0077] Suppose we need to test the leakage of a cable at 50°C (323.15K), and we know that the solubility of sodium chloride at 25°C (298.15K) is 36 g / 100 g water, and the enthalpy change of the dissolution process is 4.0 kJ / mol.

[0078] calculate :

[0079] .

[0080] .

[0081] At 50°C, a maximum of 40.86 grams of salt can be dissolved in every 100 grams of water. To ensure safety and avoid oversaturation, one might choose to use a salt concentration slightly lower than this, for example 35 grams of salt / 100 grams of water, for leakage testing of cables.

[0082] After adjusting the mass ratio of salt to water in the brine solution, the brine solution is placed in a liquid storage tank.

[0083] S303: Use a liquid preheater to heat the saline solution to a second preset temperature equal to the first preset temperature.

[0084] S400, moving the cable into the heating zone by means of a conveying assembly, and when the surface temperature of the cable reaches the first preset temperature, moving the cable into a liquid storage tank;

[0085] In order to ensure that the cable reaches and maintains this temperature evenly throughout the heating process, the heating assembly includes one or more temperature sensors configured inside the barrel, which can monitor the temperature of the cable and the inside of the barrel in real time. These temperature sensors can be thermocouples or RTDs (resistance temperature detectors), which can work stably in high temperature environments and immediately feed back temperature data to the control system.

[0086] When the surface temperature of the cable reaches a first preset temperature, the control system instructs the conveying assembly to smoothly transfer the cable to the liquid storage tank based on data provided by the temperature sensor.

[0087] S500 collects and analyzes data obtained by immersing the cable and performs a comprehensive assessment of the cable's insulation and integrity.

[0088] After the cable is immersed in preheated conductive liquid, the electrical response of the cable is continuously monitored and recorded by current and voltage sensors. These data reflect the performance of the cable under electrical load, including any abnormal current leakage caused by insulation damage.

[0089] The collected data is transferred to the analysis software, where advanced algorithms are applied to process and analyze the data to identify the insulation strength and physical integrity of the cable. These algorithms may include statistical analysis, pattern recognition or machine learning techniques to identify abnormal patterns in the data that may indicate the location and severity of defects or damage. The analysis results help technicians determine whether the cable has insulation failure or structural damage, such as cracks, wear or corrosion, and evaluate the design standards and safety requirements of the cable to ensure that each part of the cable meets or exceeds its performance specifications.

[0090] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cable detection method, characterized in that: The cable detection method is applied to a cable detection device, which comprises: a housing (1) having a heating area (11) and a liquid storage tank (12) formed therein; A conveying assembly (2) is arranged on the housing (1), and the conveying assembly (2) is used to convey the cable from the heating area (11) to the liquid storage tank (12); A heating component (3) is arranged in the heating zone (11), and the heating component (3) is used to heat the cable in the heating zone (11) to a first preset temperature, wherein the first preset temperature is lower than the maximum tolerable temperature of the cable; A liquid preheater (4) is disposed in the liquid storage tank (12), the liquid preheater (4) is in contact with the conductive liquid in the liquid storage tank (12), and is used to heat the conductive liquid to a second preset temperature; The heating assembly (3) comprises a cylinder (31) and a heating element (32) arranged on the cylinder (31); a cylinder cavity is formed in the cylinder (31); two opposite ends of the cylinder (31) are respectively formed with a cable inlet (311) and a cable outlet (312) which are connected to the cylinder cavity; the cable outlet (312) is arranged relative to the cable inlet (311) and close to the liquid storage tank (12); The heating element (32) is used to heat the barrel cavity to the first preset temperature, and the cable in the heating zone (11) is arranged to pass through the cable inlet (311), the barrel cavity and the cable outlet (312) in sequence; The heating element (32) extends in a spiral shape on the outer peripheral wall of the cylinder (31); The conveying assembly (2) comprises two guide wheels (21) located at opposite ends of the cylinder (31), each of the guide wheels (21) being used to support the cable so that the cable does not contact the peripheral wall of the cylinder (31); The cable detection method comprises: Determining a first preset temperature suitable for the type of cable to be tested; Setting the operating temperature of the heating component to the first preset temperature; heating the conductive liquid in the liquid storage tank to a second preset temperature equal to the first preset temperature by a liquid preheater; Move the cable into the heating zone by means of a conveying assembly, and when the surface temperature of the cable reaches the first preset temperature, move the cable into the liquid storage tank; Collect and analyze data obtained by soaking cables and conduct a comprehensive assessment of the cable's insulation and integrity; The first preset temperature is calculated by the following formula: ； in, is the first preset temperature in Kelvin (K), is the ambient temperature in Kelvin (K), Safety temperature rise, in Kelvin (K), is the heat loss coefficient in watts per square meter Kelvin (W / m²·K), A is the surface area of ​​the cable in square meters (m²), t is the heating time in seconds (s), m is the mass of the cable in kilograms (kg), is the specific heat capacity of the cable material, in joules per kilogram Kelvin (J / kg·K); exp is the exponential function of the base of the natural logarithm; The method of heating the conductive liquid in the liquid storage tank to a second preset temperature equal to the first preset temperature by a liquid preheater comprises: Select saline solution as the conductive solution; adjusting the mass ratio of salt to water in the salt water solution according to the first preset temperature; heating the saline solution to a second preset temperature equal to the first preset temperature using a liquid preheater; The mass ratio of salt to water in the saline solution is adjusted according to the first preset temperature, and is calculated by the following formula: ； in, The first preset temperature The solubility under is the reference temperature The solubility under is the enthalpy change during the dissolution process, in joules / mole (J / mol), R is the ideal gas constant, which is 8.314 J / mol·K, is the reference temperature in Kelvin (K), is the first preset temperature, in Kelvin (K).

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