Device and method for preparing cable buffer layer ablation sample by using high-temperature ablation technology

Abstract

The invention relates to a device and method for preparing a cable buffer layer ablation sample by using a high-temperature ablation technology, and the device comprises a fixing assembly which is used for clamping a cable, and the cable is coated with an insulation shielding layer and a buffer layer; the ablation assembly comprises a support and a flame generator arranged on the support, the cable is covered with the support, and the flame generator conducts an ablation experiment on the cable; the adjusting assembly is connected with the support, the adjusting assembly can drive the support to move in the axial extension direction of the cable, and the adjusting assembly can further drive the support to rotate around the axis of the cable, so that the flame generator can conduct ablation experiments on multiple positions of the cable. According to the device and the method, the ablation area of the high-voltage cable buffer layer ablation sample can be accurately controlled, meanwhile, a large number of ablation sites are prepared in a short time, and an efficient and accurate sample preparation device and method are provided for X-ray detection of the high-voltage cable buffer layer.

Description

Technical Field

[0001] The invention relates to the field of experimental technology of high-voltage power cables, and in particular to a device and method for preparing a cable buffer layer ablation sample by using high-temperature ablation technology. Background Art

[0002] In recent years, the use of power cables has become an inevitable trend, and the demand for cables with voltage levels of 110kV and above has been growing steadily. Among them, XLPE insulated cables account for a relatively high proportion in cable lines of 220kV and below. However, despite the widespread use of XLPE insulated cables, XLPE cables frequently suffer from body breakdown failures, and most of the failures occur between 4 and 9 years after commissioning, which is far less than the expected service life of 30 years.

[0003] Fault analysis shows that white powder and burning phenomena appear on the surface of the insulation shield and the buffer layer. These faults are highly latent and have a wide impact, seriously threatening the safety and stability of the power grid. Although existing research on the discharge ablation defects of the cable buffer layer has gradually attracted attention, there is currently no unified standard to make detailed provisions for the buffer layer area, resulting in differences in raw materials, structure, and production process of the buffer layer of different faulty cables, and the ablation mechanism lacks a unified explanation. In addition, when using X-ray detection technology to detect faults in the cable buffer layer, due to the high randomness of the ablation process itself, it is usually necessary to analyze the damage of the insulation shielding layer after ablation to perform fault detection; this analysis method not only increases the technical complexity of the detection process, but also increases the difficulty of preparing ablated samples.

[0004] For example: Patent application No. 202010718975.3 discloses a rotary stepping cable buffer layer ablation fault simulation device and method, through which the ablation process of the high-voltage cable buffer layer can be simulated quickly, conveniently and efficiently, and the mass production of buffer layer ablation samples under different external applied voltage amplitudes can be achieved in a short time;

[0005] Another example: The patent application document with application number 201911205046.6 discloses a cable buffer layer ablation detection system and method based on an X-ray machine, the detection system comprising: a buffer layer fault cable, an X-ray machine, an X-ray machine reflector, an adjustment device and a display device; the adjustment device comprises a first adjustment plate, a second adjustment plate and a connecting rod, and the first adjustment plate and the second adjustment plate are connected by a connecting rod; the buffer layer fault cable and the X-ray machine reflector are arranged on the first adjustment plate, and the X-ray machine reflector is arranged on the rear side of the buffer layer fault cable; when the X-ray light emitted by the X-ray machine irradiates the buffer layer fault cable, the X-ray light is projected through the buffer layer fault cable onto the X-ray reflector, and the density is displayed through the display device connected to the X-ray machine reflector to determine whether the buffer layer fault cable has ablation.

[0006] However, the main disadvantages of the above-mentioned existing buffer layer ablation experimental equipment and methods are that they can only test and evaluate the electrical properties of a small number of buffer layer samples, cannot prepare a large number of buffer layer and insulation shielding layer ablation samples in a short time, cannot simulate the aluminum bellows-water-blocking buffer layer structure inside the real high-voltage transmission cable in the laboratory, and cannot reproduce the buffer layer ablation failure under real working conditions. Summary of the invention

[0007] To this end, the technical problem to be solved by the present invention is to overcome the defects of the buffer layer ablation experimental device and method in the prior art, and to provide a device and method for preparing cable buffer layer ablation samples using high-temperature ablation technology, which can achieve the efficient preparation of a large number of cable buffer layer and insulation shielding layer ablation samples in a short time, and at the same time can simulate the buffer layer structure inside the real high-voltage transmission cable under laboratory conditions, and effectively reproduce the buffer layer ablation failure under real working conditions.

[0008] In order to solve the above technical problems, the present invention provides a device for preparing a cable buffer layer ablation sample using high temperature ablation technology, comprising:

[0009] A fixing assembly, used for clamping a cable, wherein the cable is coated with: an insulating shielding layer and a buffer layer;

[0010] The ablation assembly comprises: a bracket and a flame generator arranged on the bracket, wherein the bracket cover is arranged outside the cable, the flame generator performs an ablation test on the cable, and the flame generator can adjust the size and hardness of the flame;

[0011] An adjusting component is connected to the bracket, and the adjusting component can drive the bracket to move along the axial extension direction of the cable, and the adjusting component can also drive the bracket to rotate around the axis of the cable, so that the flame generator can perform ablation experiments on multiple positions of the cable.

[0012] In one embodiment of the present invention, the flame generator comprises: a nozzle, in which an ignition device, a combustion chamber, an air hole and a fuel hole are arranged, and the air hole and the fuel hole are connected to the combustion chamber.

[0013] In one embodiment of the present invention, the flame generator further includes: an air screw cap, in which an air baffle whose thickness varies with angle is arranged, the air baffle can cover the fuel hole, and rotating the air screw cap can adjust the degree of covering of the fuel hole by the air baffle.

[0014] In one embodiment of the present invention, the support comprises:

[0015] An outer support member, which is in a semicircular arc structure, and the outer support member is connected to the adjustment assembly;

[0016] The two inner support members are hingedly fixed on the outer support member via a hinge shaft, and the opening and closing angles of the two inner support members can be adjusted by rotating the two inner support members along the hinge shaft.

[0017] In one embodiment of the present invention, the ablation components are respectively disposed on the two inner support members.

[0018] In one embodiment of the present invention, the outer bracket is connected to the adjusting assembly via a slider or a gear, and the outer bracket can rotate relative to the adjusting assembly.

[0019] In one embodiment of the present invention, the fixing assembly comprises: two fixing clamps, and the two fixing clamps respectively clamp two ends of the cable.

[0020] In one embodiment of the present invention, the adjustment component includes a multi-axis transfer module and a multi-axis robotic arm. The multi-axis transfer module drives the ablation component to move horizontally in three axes in space, and the multi-axis robotic arm drives the ablation component to rotate in three axes in space.

[0021] In one embodiment of the present invention, it further comprises: an experimental cabin, the experimental cabin comprising: a base, a frame and a protective cover, and the fixing component, the ablation component and the adjustment component are all arranged in the experimental cabin.

[0022] In order to solve the above technical problems, the present invention also provides a method for preparing a cable buffer layer ablation sample using high temperature ablation technology, using the above device, comprising the following steps:

[0023] S1. Dry the experimental environment and ensure that it is sealed;

[0024] S2. Install the cable on the fixed assembly so that the insulating shielding layer and the buffer layer covering the cable are in an overhead state;

[0025] S3. The ablation assembly is driven to move by adjusting the assembly so that the ablation assembly faces the center of one side of the cable, and then the positions of the flame generators at both ends of the ablation assembly are adjusted so that the flame generators and the diameter of the cable cross-section circle are at the same level;

[0026] S4, adjusting the flame generator to generate a flame of the desired size and hardness, adjusting the position of the ablation component by the moving component, so that the buffer layer sample is slowly ablated under the flame intensity; setting the moving component to move at a speed of 0.5 cm / min until an ablation hole of a specified diameter is formed, and stopping the experiment;

[0027] S5. Repeat the above operation until ablation points with equal spacing are obtained on the sample, and a plurality of buffer layer ablation samples are obtained.

[0028] S6. Take out the ablated sample and perform subsequent X-ray photography to detect and analyze the internal structure and potential faults of the cable buffer layer.

[0029] The above technical solution of the present invention has the following advantages compared with the prior art:

[0030] 1. The present invention causes the ablation component to undergo horizontal displacement and coaxial rotation by moving the component, thereby changing the ablation position of the firing component and the buffer layer experiment without repeatedly disassembling the experimental sample. On this basis, by adjusting the flame generator, the buffer layer can be ablated under conditions of different flame sizes and hardness, and a large number of buffer layer ablation samples can be prepared in a short time;

[0031] 2. The components of the present invention are simple in structure, easy to install and remove, making the experiment intuitive and convenient, and greatly simplifying the experimental process.

[0032] 3. Overall, the equipment has the advantages of simple structure, easy operation and low cost. The method steps are simple and the operability is strong. It can be widely used in high-voltage cable buffer layer ablation simulation experiments. It can efficiently prepare a large number of cable buffer layer and insulation shielding layer ablation samples in a short time, and provide a reliable experimental platform for high-voltage cable buffer layer ablation fault analysis and verification. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein

[0034] Figure 1 It is a schematic diagram of the overall structure of a device for preparing a cable buffer layer ablation sample using high temperature ablation technology according to the present invention;

[0035] Figure 2 is a schematic structural diagram of the ablation assembly of the present invention;

[0036] Figure 3 It is a schematic structural diagram of the nozzle of the present invention;

[0037] Figure 4 It is a schematic structural diagram of the air baffle of the present invention.

[0038] Explanation of the reference numerals in the specification: 1. Fixing assembly; 2. Ablation assembly; 21. Bracket; 211. Outer support member; 212. Articulated shaft; 213. Inner support member; 22. Flame generator; 221. Nozzle; 2211. Ignition device; 2212. Combustion chamber; 2213. Air hole; 2214. Fuel hole; 222. Air screw cap; 2221. Air baffle; 3. Adjustment assembly; 4. Experimental cabin. DETAILED DESCRIPTION

[0039] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0040] Example 1

[0041] Reference Figure 1 As shown, the present invention discloses a device for preparing a cable buffer layer ablation sample using high temperature ablation technology, comprising: a fixing component 1, an ablation component 2 and an adjustment component 3, wherein:

[0042] The fixing assembly 1 is used to clamp the cable. In this embodiment, the cable is provided with: an insulating shielding layer and a buffer layer, wherein: the buffer layer adopts an aluminum bellows-water-blocking buffer layer structure, which is used to simulate the buffer layer ablation failure in real situations;

[0043] In other embodiments, buffer layer structures with other structures may also be provided, corresponding to the buffer layer of the real structure.

[0044] In this embodiment, the fixing component 1 includes: two fixing clamps, which respectively clamp the two ends of the cable, so that the cable can be suspended, and the ablation component 2 and the adjustment component 3 can move around the cable to change the ablation position.

[0045] Specifically, the force applied when the fixing clamp is closed is controlled at 5-10N to ensure that the sample is firmly fixed while avoiding damage to the material.

[0046] The ablation assembly 2 includes: a bracket 21 and a flame generator 22 arranged on the bracket 21. The bracket 21 is covered outside the cable. The flame generator 22 performs an ablation experiment on the cable. In this embodiment, the flame generator 22 can adjust the flame size and hardness, so as to realize ablation of the buffer layer under different flame sizes and hardness conditions, and prepare a large number of buffer layer ablation samples in a short time.

[0047] The adjusting component 3 is connected to the bracket 21, and the adjusting component 3 can drive the bracket 21 to move along the axial extension direction of the cable, and the adjusting component 3 can also drive the bracket 21 to rotate around the axis of the cable, so that the flame generator 22 can perform ablation experiments on multiple positions of the cable, and change the ablation positions of the firing component and the buffer layer experiment without repeatedly disassembling the experimental samples.

[0048] The device of the present invention for preparing cable buffer layer ablation samples using high-temperature ablation technology can be widely used in high-voltage cable buffer layer ablation simulation experiments, and can efficiently prepare a large number of cable buffer layer and insulation shielding layer ablation samples in a short time, providing a reliable experimental platform for high-voltage cable buffer layer ablation fault analysis and verification.

[0049] Reference Figure 2 and Figure 3 As shown, the flame generator 22 includes: a nozzle 221, in which an ignition device 2211, a combustion chamber 2212, an air hole 2213 and a fuel hole 2214 are arranged, and the air hole 2213 and the fuel hole 2214 are connected to the combustion chamber 2212, and the oxygen in the air and the fuel required for combustion are respectively introduced into the combustion chamber 2212 from the air hole 2213 and the fuel hole 2214 to be mixed, ignited by the ignition device 2211, and then burned and ejected from the nozzle 221.

[0050] Specifically, according to actual usage requirements, the aperture size of the air hole 2213 is 10-12 mm, which can ensure sufficient oxygen for the fuel to burn fully. The aperture size of the fuel hole 2214 is 2-4 mm, which can make the fuel and oxygen gas fully mixed and fully burned in the combustion chamber 2212.

[0051] Specifically, the fuel may preferably be acetylene gas.

[0052] Reference Figure 2 and Figure 4 As shown, the flame generator 22 also includes: an air screw cap 222, in which an air baffle 2221 whose thickness varies with the angle is arranged, and the air baffle 2221 can block the fuel hole 2214, and the angle control range of the air screw cap 222 is 0 to 360°. Rotating the air screw cap 222 can make different thickness positions on the air baffle 2221 block the fuel hole 2214, and adjust the degree of blocking of the fuel hole 2214 by the air baffle 2221, so as to adjust the size and hardness of the flame.

[0053] Reference Figure 2As shown, the bracket 21 includes: an outer support member 211, a hinge shaft 212 and an inner support member 213, wherein: the outer support member 211 is a semicircular arc structure similar to a "C" shape, the outer arc of the outer support member 211 is connected to the adjustment component 3, and the opening of the outer support member 211 can be covered outside the cable; two inner support members 213 are arranged in the outer support member 211, and the two inner support members 213 are hingedly fixed to the outer support member 211 through the hinge shaft 212. The two inner support members 213 are rotated along the hinge shaft 212. According to different cable pair diameters, the opening and closing angles of the two inner support members 213 can be adjusted, thereby improving the applicability of the device, and the ablation components 2 are respectively arranged on the two inner support members 213. The two ablation components 2 are used to perform synchronous ablation on both sides of the cable. Compared with unilateral ablation, it is ensured that both sides of the cable are heated more evenly.

[0054] Specifically, the bracket 21 is made of high temperature resistant material, for example, stainless steel is used to make the bracket 21, which can not only be used under high temperature conditions but also ensure stability for long-term use.

[0055] Specifically, in this embodiment, in order to achieve multi-point ablation, it is necessary to change the angle of the bracket 21 relative to the cable. Therefore, two technical solutions for changing the angle of the bracket 21 are adopted in this embodiment:

[0056] 1. Change the connection position between the outer bracket 21 and the adjusting assembly 3, and set the outer bracket 21 and the adjusting assembly 3 to be connected through a slider or a gear, so that the outer bracket 21 can rotate relative to the adjusting assembly 3.

[0057] 2. The adjusting component 3 itself is provided with the ability of multi-axis movement and rotation. The adjusting component 3 is provided to include a multi-axis transfer module and a multi-axis robotic arm. The multi-axis transfer module drives the ablation component 2 to move horizontally in three axes in space, and the multi-axis robotic arm drives the ablation component 2 to rotate in three axes in space. The multi-axis transfer module and the multi-axis robotic arm can drive the external bracket 21 to move to any angle and any position relative to the cable.

[0058] Reference Figure 1 As shown, in order to ensure the safety and airtightness of the experiment, the device of the present invention also includes: an experimental cabin 4, the experimental cabin 4 includes: a base, a frame and a protective cover, the fixing component 1, the ablation component 2, and the adjustment component 3 are all arranged in the experimental cabin 4, and the experimental device can be isolated by the protective cover to ensure the safety and airtightness of the experiment, and the protective cover is configured as a transparent cover that can be opened and closed. On the one hand, it is convenient to take and put the cable, and on the other hand, it ensures that the experimental process is clearly visible and convenient to quickly judge the ablation state.

[0059] Example 2

[0060] On the basis of the above embodiment 1, the present invention further discloses a method for preparing a cable buffer layer ablation sample using high temperature ablation technology, using the device described in any one of claims 1 to 8, characterized in that it comprises the following steps:

[0061] S1. Dry the experimental environment and ensure that it is sealed;

[0062] S2, installing the cable on the fixing assembly 1, so that the insulating shielding layer and the buffer layer covering the cable are in an overhead state;

[0063] S3, driving the ablation assembly 2 to move by adjusting the assembly 3, so that the ablation assembly 2 is directly facing the center position of one side of the cable, and then adjusting the positions of the flame generators 22 at both ends of the ablation assembly 2, so that the flame generators 22 and the diameter of the cable cross-section circle are at the same level;

[0064] S4, adjusting the flame generator 22 to generate a flame of the required size and hardness, adjusting the position of the ablation component 2 by the moving component, so that the buffer layer sample is slowly ablated under the flame intensity; setting the moving component to move at a speed of 0.5 cm / min until an ablation hole of a specified diameter is formed, and stopping the experiment;

[0065] S5. Repeat the above operation until ablation points with equal spacing are obtained on the sample, and a plurality of buffer layer ablation samples are obtained.

[0066] S6. Take out the ablated sample and perform subsequent X-ray photography to detect and analyze the internal structure and potential faults of the cable buffer layer.

[0067] Specifically, in step S1, the experimental chamber 4 is set to ensure the sealing state of the experimental environment. The specific steps of the drying operation in the experimental chamber 4 are: open the protective cover of the buffer layer ablation experimental unit, use non-woven fabric to wipe the components of the buffer layer ablation experimental unit, and then vacuum dry the components. The drying temperature is 80°C to 100°C, the drying vacuum degree is less than 0.01Mpa, and the drying time is 24h to 36h.

[0068] Specifically, in step S2, a fixed clamp is used to clamp the cable, and the force applied when the clamp is closed is controlled to be 5-10N to ensure that the sample is firmly fixed while avoiding damage to the material.

[0069] Specifically, in step S4, the ablation point of the buffer layer should be changed after the ablation degree reaches the preset degree of the experiment. The preset degree should be specifically set according to the needs of the researchers. Generally, the degree is quantified by time, and the specific time is about 10 minutes, which is adjusted according to different ablation requirements.

[0070] Specifically, in step S5, the positions of the flame generators 22 at both ends of the ablation assembly 2 are adjusted, and the angle adjustment range is 0-360°. The position of the ablation assembly 2 should be calibrated once after every 10 ablations to maintain the ablation accuracy.

[0071] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A device for preparing a cable buffer layer ablation sample using high temperature ablation technology, characterized in that: include: A fixing assembly, used for clamping a cable, wherein the cable is coated with: an insulating shielding layer and a buffer layer; The ablation assembly comprises: a bracket and a flame generator arranged on the bracket, wherein the bracket cover is arranged outside the cable, the flame generator performs an ablation test on the cable, and the flame generator can adjust the size and hardness of the flame; An adjusting component is connected to the bracket, and the adjusting component can drive the bracket to move along the axial extension direction of the cable, and the adjusting component can also drive the bracket to rotate around the axis of the cable, so that the flame generator can perform ablation experiments on multiple positions of the cable.

2. The device for preparing a cable buffer layer ablation sample using high temperature ablation technology according to claim 1, characterized in that: The flame generator comprises a nozzle, in which an ignition device, a combustion chamber, an air hole and a fuel hole are arranged, and the air hole and the fuel hole are communicated with the combustion chamber.

3. The device for preparing a cable buffer layer ablation sample using high temperature ablation technology according to claim 2, characterized in that: The flame generator also includes: an air screw cap, in which an air baffle with a thickness that varies with the angle is arranged, and the air baffle can cover the fuel hole. Rotating the air screw cap can adjust the degree to which the air baffle covers the fuel hole.

4. The device for preparing a cable buffer layer ablation sample using high temperature ablation technology according to claim 1, characterized in that: The support comprises: An outer support member, which is in a semicircular arc structure, is connected to the adjustment assembly; The two inner support members are hingedly fixed on the outer support member via a hinge shaft, and the opening and closing angles of the two inner support members can be adjusted by rotating the two inner support members along the hinge shaft.

5. The device for preparing a cable buffer layer ablation sample using high temperature ablation technology according to claim 4, characterized in that: The ablation components are respectively arranged on the two inner support members.

6. The device for preparing a cable buffer layer ablation sample using high temperature ablation technology according to claim 4, characterized in that: The outer bracket is connected to the adjusting assembly via a slider or a gear, and the outer bracket can rotate relative to the adjusting assembly.

7. The device for preparing a cable buffer layer ablation sample using high temperature ablation technology according to claim 1, characterized in that: The fixing assembly comprises: two fixing clamps, and the two fixing clamps clamp two ends of the cable respectively.

8. The device for preparing a cable buffer layer ablation sample using high temperature ablation technology according to claim 1, characterized in that: The adjustment component includes a multi-axis transfer module and a multi-axis mechanical arm. The multi-axis transfer module drives the ablation component to move horizontally in three axes in space, and the multi-axis mechanical arm drives the ablation component to rotate in three axes in space.

9. The device for preparing a cable buffer layer ablation sample using high temperature ablation technology according to claim 1, characterized in that: Also includes: The experimental cabin comprises a base, a frame and a protective cover. The fixing component, the ablation component and the adjustment component are all arranged in the experimental cabin.

10. A method for preparing a cable buffer layer ablation sample using high temperature ablation technology, using the device according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Dry the experimental environment and ensure that it is sealed; S2. Install the cable on the fixed assembly so that the insulating shielding layer and the buffer layer covering the cable are in an overhead state; S3. The ablation assembly is driven to move by adjusting the assembly so that the ablation assembly faces the center of one side of the cable, and then the positions of the flame generators at both ends of the ablation assembly are adjusted so that the flame generators and the diameter of the cable cross-section circle are at the same level; S4, adjusting the flame generator to generate a flame of the desired size and hardness, adjusting the position of the ablation component by the moving component, so that the buffer layer sample is slowly ablated under the flame intensity; setting the moving component to move at a speed of 0.5 cm / min until an ablation hole of a specified diameter is formed, and stopping the experiment; S5. Repeat the above operation until ablation points with equal spacing are obtained on the sample, and a plurality of buffer layer ablation samples are obtained. S6. Take out the ablated sample and perform subsequent X-ray photography to detect and analyze the internal structure and potential faults of the cable buffer layer.

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