1. The utility model provides a cable buffer layer ablation process resistance measuring device which characterized in that: the device comprises an ablation shielding box, a rotating bracket, an electrode plate, a probe joint, a grounding base, a measurement loop unit and a power frequency voltage loop unit;

the bottom end of the rotating bracket penetrates through the top wall of the ablation shielding box, the rotating bracket is rotatably connected with the top wall of the ablation shielding box, and the bottom end of the rotating bracket is respectively provided with a probe connector and an electrode plate; the grounding base is positioned on the inner bottom wall of the ablation shielding box, the cable buffer layer is positioned on the grounding base, one end of the electrode plate is connected with the power frequency voltage loop unit through a lead, and the rotary support moves downwards to enable the probe connector or the electrode plate to be in contact with the cable buffer layer; the measuring loop unit is connected with the probe joint.

2. The apparatus for measuring the resistance of the cable buffer layer in the ablation process according to claim 1, wherein: and a heating electric furnace is arranged above the ablation shielding box.

3. The apparatus for measuring the resistance of the cable buffer layer in the ablation process according to claim 2, wherein: the heating electric furnace and the top wall of the ablation shielding box are provided with communicated first through holes, sleeves are arranged in the first through holes, and the rotating support is located in the sleeves.

4. The apparatus for measuring the resistance of the cable buffer layer in the ablation process according to claim 2, wherein: annular slotted holes are formed in the top walls of the electric heating furnace and the ablation shielding box, cabin penetrating connectors are arranged in the annular slotted holes and rotate along the annular slotted holes, one ends of the cabin penetrating connectors are connected with the electrode plates through leads, and the other ends of the cabin penetrating connectors are connected with the power frequency voltage loop unit through leads.

5. The apparatus for measuring the resistance of the cable buffer layer in the ablation process according to claim 1, wherein: the resistance measuring device for the cable buffer layer ablation process further comprises a first sub-support and a second sub-support, the cross sections of the first sub-support and the second sub-support are L-shaped, the first sub-support and the second sub-support are located at the bottom end of the rotating support, a wiring terminal is arranged at the tail end of the first sub-support and connected with the probe connector, and the tail end of the second sub-support is connected with the top wall of the electrode plate.

6. The apparatus for measuring the resistance of the cable buffer layer in the ablation process according to claim 1, wherein: the probe connector is a four-probe connector, and the needle points of the four-probe connector and the bottom wall of the electrode plate are located on the same horizontal plane.

7. The apparatus for measuring the resistance of the cable buffer layer in the ablation process according to claim 1, wherein: the measuring circuit unit comprises a first voltmeter, a first current source and a measuring shielding box, the first voltmeter and the first current source are located in the measuring shielding box, the measuring shielding box is located on the side wall of the rotary support, the first voltmeter is connected with the two middle probes of the four probe joints through a wire buried in the rotary support in an embedded mode, and the first current source is connected with the two probes outside the four probe joints through a wire buried in the rotary support in an embedded mode.

8. The apparatus for measuring the resistance of the cable buffer layer in the ablation process according to claim 1, wherein: the power frequency voltage loop unit comprises a second voltmeter, an ammeter, a fuse, a step-up transformer and a voltage source, the voltage source is connected with the fuse in series, the fuse is connected into the input end of the step-up transformer, the output end of the step-up transformer is connected with the second voltmeter in parallel, the output end of the step-up transformer is connected with the ammeter in series, one end of the second voltmeter is connected with the cabin penetrating connector through a wire, and the other end of the second voltmeter is connected with the grounding base through a wire.

9. The apparatus for measuring the resistance of the cable buffer layer in the ablation process according to claim 1, wherein: the resistance measuring device in the cable buffer layer ablation process further comprises a spring pressurizing device, wherein the spring pressurizing device comprises an elastic piece, a screw, a rotating seat and an insulating shell;

the one end of insulating casing is connected with runing rest's top, wall connection in the one end of elastic component and the insulating casing, the other pot head of elastic component is established on the screw, the nut diameter of screw is greater than the spring external diameter, the one end and the insulating casing roof threaded connection of roating seat, the other end of roating seat is located the insulating casing outside, the roating seat down removes and causes the elastic component compression.

10. A resistance measuring method using the resistance measuring apparatus for cable buffer layer ablation process according to any one of claims 1 to 9, characterized in that: the method comprises the following steps:

(1) placing a cable buffer layer on a grounding base in an ablation shielding box, rotating a rotating support, then pressing the rotating support, moving the rotating support downwards to enable an electrode plate to be in contact with the cable buffer layer, starting a power frequency voltage loop unit, applying voltage to the cable buffer layer through a lead, and closing the power frequency voltage loop unit after a preset state is reached;

(2) rotating the rotating support to enable the probe joint to contact the cable buffer layer, and measuring the resistance of the cable buffer layer through the measuring loop unit;

(3) and (3) repeating the steps (1) and (2) until the buffer layer is obviously ablated, and obtaining the resistance of each stage in the ablation process of the cable buffer layer.

Background

The acceleration of the urbanization process brings about the increase of the ground entering amount of the high-voltage cable and also aggravates the potential electric power safety risk. The buffer layer is an important component of the high-voltage cable, can effectively ensure the electrical contact between the aluminum sheath and the insulation shield, and solves the problem of the mismatch of the thermal expansion rates between the insulation part of the cable and the aluminum sheath. In addition, the buffer layer has water resistance, and the buffer layer can expand rapidly after absorbing water, fill the gap between the buffer layer and the corrugated aluminum sheath and prevent water from longitudinally permeating.

At present, special standards are lacked for standardizing the buffer layer materials, and cable manufacturers are difficult to determine the quality requirements during purchasing, so that the phenomenon of insufficient quality sometimes occurs, and the product difference among different manufacturers is large. In recent years, domestic power operation enterprises frequently find the phenomenon of ablation caused by discharge of a buffer layer of an operation cable, and the industry roughly proposes the reasons of ablation caused by concentration of capacitance and current, ablation caused by electrochemical corrosion, ablation caused by discharge of the buffer layer and an aluminum sheath, ablation caused by circulation of a metal sheath and the like. According to the reason analysis, the influence of structural factors of the cable is eliminated, and a large number of researches show that the white powder spots at the ablation part of the buffer layer are closely related to the water-blocking powder in the buffer layer, so that the resistance between the buffer layer and the metal sheath is increased, and the ablation is caused.

The patent application with publication number CN111929544A discloses a device and a method for simulating ablation faults of a cable buffer layer with adjustable current and surface pressure, which simulate ablation conditions of the buffer layer under different currents and surface pressures, but do not realize measurement of resistance in the ablation process of the buffer layer.

Disclosure of Invention

The invention aims to provide a resistance measuring device and a resistance measuring method for simulating the whole process of cable buffer layer ablation.

The invention solves the technical problems through the following technical means:

the invention provides a resistance measuring device for a cable buffer layer ablation process, which comprises an ablation shielding box, a rotating bracket, an electrode plate, a probe joint, a grounding base, a measuring loop unit and a power frequency voltage loop unit, wherein the ablation shielding box is arranged on the outer side of the cable buffer layer;

the bottom end of the rotating bracket penetrates through the top wall of the ablation shielding box, the rotating bracket is rotatably connected with the top wall of the ablation shielding box, and the bottom end of the rotating bracket is respectively provided with a probe connector and an electrode plate; the grounding base is positioned on the inner bottom wall of the ablation shielding box, the cable buffer layer is positioned on the grounding base, one end of the electrode plate is connected with the power frequency voltage loop unit through a lead, and the rotary support moves downwards to enable the probe connector or the electrode plate to be in contact with the cable buffer layer; the measuring loop unit is connected with the probe joint.

The working principle is as follows:

(1) the cable buffer layer is placed on the grounding base, the rotating support is rotated, then the rotating support is pressed, the electrode plate is in contact with the cable buffer layer, the power frequency voltage loop unit is started, voltage is applied to the cable buffer layer, and the power frequency voltage loop unit is closed after the cable buffer layer reaches a preset state.

(2) And rotating the rotating support to enable the probe joint to contact the cable buffer layer, and measuring the resistance and the resistivity of the cable buffer layer through the measuring loop unit.

(3) And (3) repeating the steps (1) and (2) until the buffer layer is obviously ablated, and obtaining the resistance and the resistivity of each stage in the ablation process of the cable buffer layer.

Has the advantages that: the device has a simple structure, can be quickly switched between high-voltage ablation simulation and resistance measurement of the cable buffer layer, and can obtain resistance change parameters of each stage in the ablation process of the cable buffer layer.

Preferably, a heating electric furnace is arranged above the ablation shielding box.

Preferably, the electric heating furnace and the top wall of the ablation shielding box are provided with communicated first through holes, sliding bearings are arranged in the first through holes, and the rotating support is connected with the sliding bearings.

Has the advantages that: in the process of electrification of the high-temperature cable, the temperature of a cable buffer layer is generally 70-80 ℃, the electric heating furnace can enable the cable buffer layer to reach the thermal balance of 70-80 ℃ before an experiment is started, actual working conditions can be simulated more truly, and the rotating support can move up and down along the axis of the sliding bearing through the sliding bearing and can rotate at the same time.

Preferably, the electric heating furnace and the top wall of the ablation shielding box are provided with communicated first through holes, sleeves are arranged in the first through holes, and the rotating support is located in the sleeves.

The working principle is as follows: the friction between the side wall of the rotating support and the inner side wall of the sleeve is adjusted to enable the friction to be larger than the gravity of the rotating support, the rotating support cannot drop due to the gravity, and the rotating support can move downwards along the axis of the sleeve after being pressed.

Preferably, annular slotted holes are formed in the top walls of the electric heating furnace and the ablation shielding box, cabin penetrating connectors are arranged in the annular slotted holes and rotate along the annular slotted holes, one ends of the cabin penetrating connectors are connected with the electrode plates through leads, and the other ends of the cabin penetrating connectors are connected with the power frequency voltage loop unit through leads.

Has the advantages that: the inner part of the box body can be shielded and protected through the cabin penetrating connector, and the influence of electric furnace heating and external voltage on the circuit is reduced. When the rotary bracket is rotated, the cabin penetrating connector can rotate along with the rotary bracket in the annular groove hole.

Preferably, the resistance measuring device in the cable buffer layer ablation process further comprises a first sub-support and a second sub-support, the cross sections of the first sub-support and the second sub-support are both L-shaped, the first sub-support and the second sub-support are both located at the bottom end of the rotating support, a wiring terminal is arranged at the tail end of the first sub-support and connected with the probe connector, and the tail end of the second sub-support is connected with the top wall of the electrode plate.

Preferably, the probe connector is a four-probe connector, and the needle tips of the four-probe connector and the bottom wall of the electrode plate are located on the same horizontal plane.

Has the advantages that: the measuring range of the four-probe joint can be very small, so that different ablation areas of ablation experimental materials can be selected for resistance measurement.

Preferably, the measurement loop unit comprises a first voltmeter, a first current source and a measurement shielding box, the first voltmeter and the first current source are located in the measurement shielding box, the measurement shielding box is located on the side wall of the rotary support, the first voltmeter is connected with the two middle probes of the four probe joints through a wire buried in the rotary support, and the first current source is connected with the two probes outside the four probe joints through a wire buried in the rotary support.

Preferably, power frequency voltage loop unit includes second voltmeter, ampere meter, fuse, step up transformer and voltage source, voltage source and fuse series connection, the fuse inserts step up transformer's input, step up transformer's the parallelly connected second voltmeter of output, step up transformer's the output series connection ampere meter, the one end of second voltmeter is passed through the wire and is connected with the cross cabin connector, the other end of second voltmeter passes through the wire and is connected with ground connection base.

Preferably, the cable buffer layer ablation process resistance measuring device further comprises a spring pressurizing device, wherein the spring pressurizing device comprises an elastic piece, a screw, a rotating seat and an insulating shell;

the one end of insulating casing is connected with runing rest's top, wall connection in the one end of elastic component and the insulating casing, the other pot head of elastic component is established on the screw, the nut diameter of screw is greater than the spring external diameter, the one end and the insulating casing roof threaded connection of roating seat, the other end of roating seat is located the insulating casing outside, the roating seat down removes and causes the elastic component compression.

The working principle is as follows: and the rotating base is rotated, one end of the rotating base presses a nut of the screw to enable the screw to press the elastic piece, and the rotating support can move downwards along the axis of the sliding bearing or the axis of the sleeve by adjusting the pressing force of the elastic piece.

Has the advantages that: the pressure among the electrode plate, the four-probe connector and the cable buffer layer is adjusted through the spring pressurizing device, so that the air gap is reduced, and the measurement precision is improved.

Preferably, the resistance measuring device for the cable buffer layer ablation process further comprises a moving unit, the moving unit comprises a leading-out shaft and a track, a second through hole is formed in the bottom wall of the ablation shielding box, one end of the leading-out shaft is connected with the side wall of the grounding base, and the other end of the leading-out shaft extends out of the second through hole and is connected with the track in a sliding mode.

Has the advantages that: the shaft is led out through moving, the movement of the grounding base is realized, and the cable buffer layer is positioned on the grounding base, so that the relative positions of the four probe connectors and the cable buffer layer are changed, and the resistance of the cable buffer layer at different positions can be measured.

The invention also provides a resistance measuring method adopting the resistance measuring device in the cable buffer layer ablation process, which comprises the following steps:

(1) placing a cable buffer layer on a grounding base in an ablation shielding box, rotating a rotating support, then pressing the rotating support, moving the rotating support downwards to enable an electrode plate to be in contact with the cable buffer layer, starting a power frequency voltage loop unit, applying voltage to the cable buffer layer through a lead, and closing the power frequency voltage loop unit after a preset state is reached;

(2) rotating the rotating support to enable the probe joint to contact the cable buffer layer, and measuring the resistance of the cable buffer layer through the measuring loop unit;

(3) and (3) repeating the steps (1) and (2) until the buffer layer is obviously ablated, and obtaining the resistance of each stage in the ablation process of the cable buffer layer.

The working principle of the invention is as follows:

(1) the cable buffer layer is placed on a grounding base in the ablation shielding box, the rotary support is rotated, then the rotary support is pressed, the electrode plate is in contact with the cable buffer layer, the power frequency voltage loop unit is started, voltage is applied to the cable buffer layer, and the power frequency voltage loop unit is closed after the cable buffer layer reaches a preset state.

(2) And rotating the rotating support to enable the probe joint to contact the cable buffer layer, and measuring the resistance and the resistivity of the cable buffer layer through the measuring loop unit.

(3) And (3) repeating the steps (1) and (2) until the buffer layer is obviously ablated, and obtaining the resistance and the resistivity of each stage in the ablation process of the cable buffer layer.

The invention has the advantages that: the device has a simple structure, can be quickly switched between high-voltage ablation simulation and resistance measurement of the cable buffer layer, and can obtain resistance change parameters of each stage in the ablation process of the cable buffer layer.

In the process of electrification of the high-temperature cable, the temperature of a cable buffer layer is generally 70-80 ℃, the electric heating furnace can enable the cable buffer layer to reach the thermal balance of 70-80 ℃ before an experiment is started, actual working conditions can be simulated more truly, and the rotating support can move up and down along the axis of the sliding bearing through the sliding bearing and can rotate at the same time.

The inner part of the box body can be shielded and protected through the cabin penetrating connector, and the influence of electric furnace heating and external voltage on the circuit is reduced. When the rotary bracket is rotated, the cabin penetrating connector can rotate along with the rotary bracket in the annular groove hole.

The measuring range of the four-probe joint can be very small, so that different ablation areas of ablation experimental materials can be selected for resistance measurement.

The pressure among the electrode plate, the four-probe connector and the cable buffer layer is adjusted through the spring pressurizing device, so that the air gap is reduced, and the measurement precision is improved.

Drawings

FIG. 1 is a schematic structural diagram of a resistance measuring device in the cable buffer layer ablation process in example 1 of the present invention;

FIG. 2 is a schematic structural diagram of a resistance measuring device in the cable buffer layer ablation process in example 3 of the present invention;

in the figure: an ablation shield box 111; a rotating bracket 112; a first sub-frame 113; a second sub-mount 114; a sliding bearing 115; an electrode pad 116; a probe connector 117; a ground base 118; an electric heating furnace 119; a cross-hatch connector 120; an insulated wire box 122; a first conductive line 123; a first voltmeter 1241; a first current source 1242; a measurement shield box 1243; a second voltmeter 1251; an ammeter 1252; a fuse 1253; a step-up transformer 1254; a voltage source 1255; an elastic member 1261; a screw 1262; a swivel base 1263; an insulating housing 1264; a take-off shaft 1281; a track 1282.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

It is noted that, in this document, relational terms such as first and second, and the like, if any, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Example 1

A resistance measuring device for a cable buffer layer ablation process is shown in fig. 1 and comprises an ablation shielding box 111, a rotating bracket 112, an electrode plate 116, a probe joint 117, a grounding base 118, a measuring loop unit and a power frequency voltage loop unit.

The ablation shielding box 111 is shaped as a rectangular parallelepiped, a cube or a cylinder according to actual needs, but is not limited to these shapes. The top wall of the ablation shielding box 111 is provided with a first through hole.

The rotating bracket 112 is cylindrical, the rotating bracket 112 is rotatably connected with the first through hole, the embodiment adopts the following manner to rotatably connect, the sliding bearing 115 is installed in the first through hole, the installation manner of the sliding bearing 115 and the first through hole is the prior art, the rotating shaft bracket is installed on the sliding bearing 115, and the rotating bracket 112 can move up and down along the axis of the sliding bearing 115, and simultaneously, the rotation is realized. The rotation connection mode in this embodiment can also be implemented by other modes in the prior art.

Ablation shielded cell 111 is stretched into to the one end of runing rest 112, ablation shielded cell 111 is stretched out to the other end of runing rest 112, for facilitating the installation electrode piece 116 and probe joint 117, this embodiment still includes first branch support 113 and second branch support 114, the cross-section of first branch support 113 and second branch support 114 is the L shape, the one end of first branch support 113 and the bottom fixed connection of runing rest 112, the other end of first branch support 113 sets up towards ablation shielded cell 111 inner bottom wall, the one end of second branch support 114 and the bottom fixed connection of runing rest 112, the other end of second branch support 114 sets up towards ablation shielded cell 111 inner bottom wall.

Four platinum wires are embedded in the first sub-bracket 113, a terminal is installed at the tail end of the first sub-bracket 113, the terminal is connected with the platinum wires, in this embodiment, the probe connector 117 is a four-probe connector 117, the four-probe connector 117 is connected with the terminal, and the falling point of the four-probe connector 117 is a straight line.

The end of the second sub-frame 114 is fixedly connected to the electrode plate 116, and the probe tip and the bottom wall of the electrode plate 116 are located at the same horizontal plane in this embodiment. The electrode sheet 116 in this embodiment may not only be a flat electrode sheet 116, but also be ablated by a corrugated aluminum sheath in the actual ablation process of the high-voltage cable, and therefore, the electrode sheet 116 may also be corrugated.

The grounding base 118 is fixedly installed on the inner bottom wall of the ablation shielding box 111, the cable buffer layer is placed on the grounding base 118, the position of the grounding base 118 is opposite to the position of the electrode plate 116 or the four probe joints 117, the rotating support 112 moves downwards to enable the electrode plate 116 or the four probe joints 117 to be in contact with the cable buffer layer, the bottom end of the grounding base 118 is connected with a first lead 123, the first lead 123 is a platinum wire, and the first lead 123 penetrates through the ablation shielding box 111 to be grounded.

In order to maintain the temperature of the cable core during the operation of the cable in the ablation shielding box 111, the present embodiment further includes an electric heating furnace 119, the electric heating furnace 119 is installed on the top wall of the ablation shielding box 111, and the first through hole on the ablation shielding box 111 penetrates through the top wall of the electric heating furnace 119.

The embodiment further comprises a cabin penetrating connector 120, the electric heating furnace 119 and the top wall of the ablation shielding box 111 are provided with annular slots, the cabin penetrating connector 120 is installed in the annular slot, the cabin penetrating connector 120 uses the rotary support 112 as a center and rotates along the annular slot, one end of the cabin penetrating connector 120 is connected with the electrode plate 116 through a second lead, the second lead is a platinum wire, an insulating wire box 122 is sleeved outside the second lead, and the second lead penetrates out of the ablation shielding box 111 and the electric heating furnace 119 through the cabin penetrating connector 120.

The measuring circuit unit comprises a first voltmeter 1241, a first current source 1242 and a measuring shielding box 1243, the first voltmeter 1241 and the first current source 1242 are both located in the measuring shielding box 1243, the measuring shielding box 1243 is fixedly installed on the side wall of the rotary bracket 112, the first voltmeter 1241 is connected with the middle two probes of the four-probe connector 117 through platinum wires embedded in the rotary bracket 112, and the first current source 1242 is connected with the two probes outside the four-probe connector 117 through wires embedded in the rotary bracket 112.

The power frequency voltage loop unit comprises a second voltmeter 1251, an ammeter 1252, a fuse 1253, a step-up transformer 1254 and a voltage source 1255, the voltage source 1255 is connected with the fuse 1253 in series, the fuse 1253 is connected to the input end of the step-up transformer 1254, the output end of the step-up transformer 1254 is connected with the second voltmeter 1251 in parallel, the output end of the step-up transformer 1254 is connected with the ammeter 1252 in series, one end of the second voltmeter 1251 is connected with the cabin penetration connector 120 through a second wire, and the other end of the second voltmeter 1251 is connected with the first wire 123.

In order to improve the measurement accuracy, the present embodiment further includes a spring pressing device, which includes an elastic member 1261, a screw 1262, a rotating seat 1263 and an insulating housing 1264, wherein the elastic member 1261 is a spring.

One end of the insulating housing 1264 is fixedly installed at the top end of the rotating bracket 112, one end of the elastic element 1261 is fixedly connected with the inner bottom wall of the insulating housing 1264, the other end of the elastic element 1261 is sleeved on the screw 1262, the nut of the screw 1262 is positioned above the elastic element 1261, and the diameter of the nut is larger than the outer diameter of the spring. One end of the rotating seat 1263 is in threaded connection with the top wall of the insulating housing 1264, the other end of the rotating seat 1263 is located outside the insulating housing 1264, the rotating seat 1263 is rotated to enable one end of the rotating seat 1263 to be in contact with the nut of the screw 1262, the rotating seat 1263 is continuously rotated to enable the rotating seat 1263 to press the screw 1262 downwards, and the rotating seat 1263 moves downwards to enable the elastic element 1261 to be compressed.

The working principle of the embodiment is as follows:

(1) the cable buffer layer is placed on the grounding base 118, the rotating support 112 is rotated, then the rotating support 112 is manually pressed or the rotating base 1263 is rotated, one end of the rotating base 1263 presses the nut of the screw 1262, the screw 1262 presses the elastic piece 1261, the rotating support 112 can move downwards along the axis of the sliding bearing 115 by adjusting the pressing force of the elastic piece 1261, so that the electrode plate 116 is in contact with the cable buffer layer, the voltage source 1255 is turned on, the voltage is slowly increased, the voltage increase is stopped when the second voltmeter 1251 displays that the preset test amplitude value is reached, and the test process and the parameter change are recorded. When the continuous test reaches the set time or open fire occurs and the value of the ammeter 1252 is suddenly increased, the voltage source 1255 is turned off.

(2) Manually moving the rotary bracket 112 upward or reversely rotating the rotary base 1263 to reduce the pressure of the spring pressing device, rotating the rotary bracket 112 to make the probe connector 117 contact with the cable buffer layer, properly increasing the pressure of the spring pressing device to make the probe connector 117 closely contact with the cable buffer layer, turning on the current source, and recording the parameters of the voltmeter.

(3) And (3) repeating the steps (1) and (2) until the buffer layer is obviously ablated, and obtaining the resistance and the resistivity of each stage in the ablation process of the cable buffer layer.

The beneficial effects of the embodiment are that: the device has a simple structure, can be quickly switched between high-voltage ablation simulation and resistance measurement of the cable buffer layer, and can obtain resistance change parameters of each stage in the ablation process of the cable buffer layer.

The electric heating furnace 119 can maintain the temperature of a wire core when the cable in the ablation shielding box 111 runs, and the rotary bracket 112 can move up and down along the axis of the sliding bearing 115 through the sliding bearing 115 and simultaneously realize rotation.

The shielding box, the measurement shielding box 1243, the cabin penetrating connector 120 and the embedded platinum wire realize shielding protection of the circuit part in the box, reduce the influence of electric furnace heating and external voltage on the electric furnace heating and the measurement range of the four-probe joint 117, and can select different ablation areas of ablation experimental materials to carry out resistance measurement.

The pressure between the electrode plate 116, the four-probe connector 117 and the cable buffer layer is adjusted through the spring pressurizing device, so that the air gap is reduced, and the measurement precision is improved.

Example 2

This embodiment is different from embodiment 1 in that: a sleeve (not shown) is fixedly installed in the first through hole, the rotating support 112 is installed in the sleeve, and the friction force between the side wall of the rotating support 112 and the inner side wall of the sleeve is adjusted to be larger than the gravity of the rotating support 112, so that the rotating support 112 cannot fall off due to the gravity, and the rotating support 112 can move downwards along the axis of the sleeve after being pressed.

Example 3

This embodiment is different from embodiment 1 or embodiment 2 in that: the ablation shielding box is characterized by further comprising a moving unit, the moving unit comprises a leading-out shaft 1281 and a rail 1282, a second through hole is formed in the bottom wall of the ablation shielding box 111, one end of the leading-out shaft 1281 is fixedly connected with the side wall of the grounding base 118, and the other end of the leading-out shaft 1281 extends out of the second through hole and is in sliding connection with the rail 1282.

Has the advantages that: through removing extraction axle 1281, realize the removal to ground connection base 118, because the cable buffer layer is located ground connection base 118 to change the relative position of four probe joint 117 and cable buffer layer, can measure the cable buffer layer resistance of different positions.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.