An electrode structure for high-voltage pulse discharge rock breaking

Abstract

The present invention discloses an electrode structure for high-voltage pulse discharge rock breaking, which belongs to the field of high voltage technology, and includes a coaxial cable, an electrode connection unit, a discharge electrode, and an explosion tube connected in sequence. It can be directly used for rock breaking, the electrode can be reused, and the metal wire can be easily replaced. Among them, the coaxial cable is used to transmit the pulse current to the discharge electrode, and a multi-core wire structure is adopted to reduce the loop inductance and resistance; the electrode connection unit includes realizing the connection between the coaxial cable and the discharge electrode, and filling the insulating material between the high-voltage electrode connection module and the grounding electrode connection module to improve the insulation capacity; the discharge electrode transmits the pulse current to the metal wire to form and maintain the plasma arc, which has high mechanical strength and ablation resistance and can be reused; the explosion tube is filled with metal wire to realize the explosion of the metal wire to generate shock waves, and the shock wave attenuation is reduced through the shock wave propagation medium to realize rock breaking.

Description

Technical Field

[0001] The present invention belongs to the field of high voltage technology, and more specifically, relates to an electrode structure for high voltage pulse discharge rock breaking. Background Art

[0002] High-voltage pulse discharge rock breaking technology is a specific way of applying pulse power technology to rock crushing. A high-current density pulse current acts on a metal wire, causing the wire to burn and vaporize within microseconds to form a plasma, which rapidly expands outward and generates a powerful shock wave in a very short time. The stress intensity generated by the shock wave is greater than the tensile strength of the rock, causing the rock to break.

[0003] High-voltage pulse discharge rock-breaking technology generates destructive force inside the rock, with low energy consumption, low crushing cost, and no pollution during the crushing process. At the same time, the metal wire material is easy to obtain, low-cost and non-hazardous, and has application advantages and development prospects in the field of rock crushing. However, high-voltage pulse discharge rock breaking relies on the shock wave generated by the expansion of the plasma channel formed by the discharge. The shock wave is severely attenuated in the air, making it difficult to effectively crush the rock. After each discharge, the metal wire needs to be replaced before the next discharge process can be carried out. The traditional metal wire replacement process requires manual connection of the metal wire across the high voltage and grounding electrodes. The metal wire replacement process is slow, which limits the efficiency of rock crushing. During the rock crushing process, the discharge electrode is used to maintain the plasma channel, and a large current will flow through it. At the same time, it is subjected to strong mechanical stress, and the electrode has a short service life. At the same time, the electrode is prone to deformation and is difficult to reuse. Summary of the invention

[0004] In view of the above defects or improvement needs of the prior art, the present invention provides an electrode structure for high-voltage pulse discharge, thereby solving the technical problems of severe shock wave attenuation, slow metal wire replacement and difficult electrode reuse in existing high-voltage pulse rock breaking devices.

[0005] To achieve the above objectives, the present invention provides an electrode structure for high-voltage pulse discharge, including a coaxial cable, an electrode connection unit, a discharge electrode, and an explosive tube connected in sequence, which can be directly applied to rock crushing, the electrode is reusable, and the metal wire is easy to replace.

[0006] The coaxial cable is used to transmit the pulse current to the discharge electrode;

[0007] The electrode connection unit includes a high-voltage electrode connection module, a ground electrode connection module and an insulating layer. The high-voltage electrode connection module is used to transmit the pulse current to the discharge electrode. The ground electrode connection module provides a return loop for the pulse current. The insulating layer is filled between the two connection modules to improve the insulation capacity of the equipment.

[0008] The discharge electrode includes a coaxially sleeved high-voltage electrode and a ground electrode, which are used to transmit pulse current to the metal wire to form and maintain a plasma arc, have high mechanical strength and ablation resistance, and can be reused;

[0009] The explosion tube is connected to the discharge electrode and is used to use pulse current to cause electric explosion of the metal wire, generate shock wave and reduce shock wave attenuation through the shock wave propagation medium, so as to achieve rock crushing.

[0010] Preferably, the discharge electrode is vertically inserted into the explosive tube. The explosive tube is damaged after the metal wire explodes. The discharge electrode is repeatedly used in conjunction with the explosive tube. Inserting the discharge electrode into the explosive tube is to replace the metal wire, thereby simplifying the process of replacing the metal wire.

[0011] Preferably, the high-voltage electrode is a cylinder made of tungsten-copper alloy to reduce electrode ablation; the grounding electrode is a tube made of brass to prevent shock waves from causing mechanical damage to the discharge electrode; insulating material is filled between the high-voltage electrode and the grounding electrode to ensure the insulation capacity of the discharge electrode and avoid short circuit. The insulating material of the discharge electrode is made into a cone at the head position with a bottom radius consistent with the outer diameter of the grounding electrode to increase the creepage distance and facilitate the insertion of the discharge electrode into the explosive tube.

[0012] Preferably, the explosion tube includes a metal wire, a metal foil and a shock wave propagation medium. The metal wire is connected to the high-voltage electrode and uses a pulse current to generate a metal wire explosion. The metal foil is connected to the ground electrode to provide a current loop. The metal wire is connected to the metal foil at the bottom of the metal wire. The first section of the metal wire is designed with a metal groove. The metal groove increases the contact area with the high-voltage electrode and reduces electrode ablation. The shock wave propagation medium is used to transmit the shock wave generated by the metal wire explosion, reduce the shock wave attenuation, and fix the metal wire and the metal foil. The shock wave transmission medium is made into a cylinder with an open upper end. The metal wire is vertically buried inside the cylinder, leaving only the metal groove. The metal foil is placed on the inner wall of the cylinder. The inner diameter of the cylinder is consistent with the outer diameter of the discharge electrode, ensuring close contact between the ground electrode and the metal foil and improving the flow capacity.

[0013] Preferably, the shock wave transmission medium is a cylinder with an open upper end.

[0014] Preferably, the high-voltage electrode connection module and the grounding electrode connection module of the electrode connection unit are crimped together with the high-voltage electrode and the grounding electrode respectively, so as to improve the current carrying capacity and the mechanical strength and current carrying capacity.

[0015] Preferably, the coaxial cable adopts a multi-core wire structure to reduce loop inductance and resistance.

[0016] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0017] 1. The present invention provides an electrode structure for high-voltage pulse discharge rock breaking, in which a shock wave propagation medium is filled around a metal wire to reduce the attenuation of the shock wave. The electrode structure can be directly applied to rock breaking.

[0018] 2. The present invention provides an electrode structure for high-voltage pulse discharge rock breaking. The discharge electrode adopts a coaxial design. The high-voltage electrode adopts tungsten-copper material, and a metal groove is designed at the upper end of the metal wire to reduce the ablation of the high-voltage electrode. The grounding electrode adopts a tube body made of brass, which plays a mechanical protection role while reflux, so that the discharge electrode can be reused.

[0019] 3. The present invention provides an electrode structure for high-voltage pulse discharge rock breaking, in which a metal wire is fixed in a shock wave propagation medium and made into an explosive tube. The discharge electrode can be directly inserted into the explosive tube to complete the replacement of the metal wire, thereby simplifying the metal wire replacement process and reducing the time consumption of metal wire replacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of an electrode structure for high-voltage pulse discharge rock breaking provided by an embodiment of the present invention;

[0021] Figure 2 A schematic diagram of a cross section and a section of a discharge electrode provided by an embodiment of the present invention;

[0022] Figure 3 A schematic cross-sectional view of an electrode connection unit provided in an embodiment of the present invention;

[0023] Figure 4 A schematic cross-sectional view of an explosion tube provided by an embodiment of the present invention;

[0024] Figure 5 A schematic diagram of on-site use of electrodes provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0026] The present invention provides an electrode structure for high-voltage pulse discharge, comprising a coaxial cable, an electrode connection unit, a discharge electrode, and an explosive tube connected in sequence. The structure can be directly applied to rock crushing, the electrode can be reused, and the metal wire can be easily replaced.

[0027] The coaxial cable is used to transmit the pulse current to the discharge electrode;

[0028] The electrode connection unit includes a high-voltage electrode connection module, a ground electrode connection module and an insulating layer. The high-voltage electrode connection module is used to transmit the pulse current to the discharge electrode. The ground electrode connection module provides a return loop for the pulse current. The insulating layer is filled between the two connection modules to improve the insulation capacity of the equipment.

[0029] The discharge electrode includes a coaxially sleeved high-voltage electrode and a ground electrode, which are used to transmit pulse current to the metal wire to form and maintain a plasma arc, have high mechanical strength and ablation resistance, and can be reused;

[0030] The explosion tube is connected to the discharge electrode and is used to use pulse current to cause electric explosion of the metal wire, generate shock wave and reduce shock wave attenuation through the shock wave propagation medium, so as to achieve rock crushing.

[0031] The embodiment of the present invention provides an electrode structure for high-voltage pulse discharge rock breaking, such as Figure 1 As shown, it includes a coaxial cable 101, an electrode connection unit 102, a discharge electrode 103, and an explosive tube 104 connected in sequence, which can be directly used for rock crushing, the electrode can be reused, and the metal wire is easy to replace.

[0032] The coaxial cable is used to transmit the pulse current to the discharge electrode. Specifically, the coaxial cable adopts a multi-core structure to reduce loop inductance and resistance. Specifically, the coaxial cable uses a RC-50-20-20 four-core coaxial cable, and the outer diameter of the coaxial cable is 20 mm.

[0033] The discharge electrode transmits pulse current to the metal wire to form and maintain a plasma arc. It has high mechanical strength and ablation resistance and can be reused.

[0034] Specifically, Figure 2 As shown, the discharge electrode includes a high-voltage electrode 201, a grounding electrode 203 and an insulating material 202. The high-voltage electrode is a column made of tungsten-copper alloy to reduce electrode ablation; the grounding electrode is a tube made of brass to prevent the shock wave from causing mechanical damage to the discharge electrode; the high-voltage electrode and the grounding electrode are filled with insulating material to ensure the insulation capacity of the discharge electrode and avoid short circuit. The insulating material of the discharge electrode is made into a cone at the head position with a bottom radius consistent with the outer diameter of the grounding electrode to increase the creepage distance along the surface and facilitate the insertion of the discharge electrode into the explosive tube.

[0035] Specifically, the high-voltage electrode is made of tungsten-copper alloy with a copper content of 90%, with a diameter of 10mm and a length of 70cm; the grounding electrode is a brass tube with an outer diameter of 30mm, an inner diameter of 24mm and a length of 64cm. The upper and lower ends of the high-voltage electrode are 3cm beyond the grounding electrode, respectively used for connection with the coaxial cable and the production of the insulating material cone. The insulating material is polycarbonate, which is filled between the high-voltage electrode and the grounding electrode. The bottom surface of the insulating material cone has a diameter of 30mm and a height of 25mm.

[0036] like Figure 3 As shown, the electrode connection unit includes a high-voltage electrode connection module 301, a grounding electrode connection module 303 and an insulating material 302. The high-voltage electrode connection module transmits the pulse current to the discharge electrode, and the grounding electrode connection module provides a return circuit for the pulse current. The insulating material is filled between the two connection modules to improve the insulation capacity of the equipment.

[0037] Specifically, the high-voltage electrode connection module and the ground electrode connection module of the electrode connection unit are respectively crimped together with the high-voltage electrode and the ground electrode to improve the current carrying capacity and the mechanical strength and current carrying capacity.

[0038] Specifically, the high-voltage electrode connection module and the grounding electrode connection module both use cylinders made of 3mm thick brass sheets, which are used to crimp the high-voltage electrode and the coaxial cable core wire, the grounding electrode and the coaxial cable grounding wire together, respectively. After the high-voltage electrode is connected to the coaxial cable core wire, an epoxy tube is inserted into the outside as an insulating material, and then the grounding electrode and the coaxial cable grounding wire are crimped.

[0039] The blasting tube is connected to the discharge electrode, and a pulse current is used to cause an electric explosion in the metal wire, thereby generating a shock wave and reducing the shock wave attenuation through the shock wave propagation medium, thereby achieving rock crushing.

[0040] Specifically, Figure 4 As shown, the explosion tube includes a metal wire 402, a metal foil 403 and a shock wave propagation medium 401. The metal wire is connected to the high-voltage electrode and uses a pulse current to generate a metal wire explosion; the metal foil is connected to the ground electrode to provide a current loop; the metal wire and the metal foil are connected at the bottom of the metal wire, and a metal groove is designed at the first section of the metal wire. The metal groove increases the contact area with the high-voltage electrode and reduces electrode ablation. The shock wave propagation medium is used to transmit the metal wire explosion to generate shock waves, reduce shock wave attenuation, and fix the metal wire and the metal foil. The shock wave transmission medium is made into a cylinder with an open upper end, and the metal wire is vertically buried inside the cylinder, leaving only the metal groove. The metal foil is placed on the inner wall of the cylinder, and the inner diameter of the cylinder is consistent with the outer diameter of the discharge electrode, ensuring close contact between the ground electrode and the metal foil, and improving the flow capacity.

[0041] Specifically, the shock wave propagation medium is made of polyethylene material, and is made into a cylinder with a length of 15 cm, an inner diameter of 30 mm, an outer diameter of 40 mm, and a hole depth of 8 cm. The metal wire is a copper wire with a diameter of 0.4 mm and a length of 3 cm. The radius of the metal groove at the upper end is 5 mm, the height is 2 mm, and the curvature is consistent with the first section of the high-voltage electrode. The metal wire is buried in the center of the cylinder, and its bottom end is 4 cm away from the lower end of the cylinder. The metal foil is a copper foil with a thickness of 0.2 mm, which is embedded in the cylinder. After the discharge electrode is inserted, the metal foil is in close contact with the discharge electrode through interference fit.

[0042] The discharge electrode can be vertically inserted into the explosive tube. The explosive tube is damaged after the metal wire explodes and the rock is crushed. The discharge electrode can be repeatedly used with the explosive tube. Inserting the discharge electrode into the explosive tube is to replace the metal wire, which simplifies the process of replacing the metal wire.

[0043] Specifically, the discharge electrode should be inserted into the explosive tube by 8 cm until the high-voltage electrode contacts the metal groove at the top of the metal wire. The explosive tube is fixed vertically on the bracket, and the discharge electrode is inserted into the explosive tube. The average time for the discharge electrode to be placed in the crushed rock in the explosive tube is 45 seconds.

[0044] Specifically, Figure 5 As shown, during the on-site implementation, the high-voltage pulse discharge rock-breaking system mainly includes a high-voltage pulse power supply 501, a coaxial cable 502, a discharge electrode 503, and an explosive tube 504 placed in the borehole. In this embodiment, the explosive tube is pre-buried in the borehole of the rock to be broken. After the discharge electrode is inserted into the explosive tube, the high-voltage pulse power supply is controlled to output a pulse current, and the coaxial cable and the discharge electrode transmit the pulse current to the explosive tube, causing a metal wire electric explosion to achieve the crushing of the rock in the area. After the explosive tube in the borehole is used, the discharge electrode is taken out and inserted into the explosive tube in the next borehole, and so on and so forth to achieve the overall crushing of the rock. In this way, the average wire replacement time is 15s, which effectively shortens the metal wire replacement time and improves the crushing efficiency.

[0045] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An electrode structure for high-voltage pulse discharge rock breaking, characterized in that: It comprises a coaxial cable (101), an electrode connection unit (102), a discharge electrode (103), and an explosion tube (104) which are connected in sequence; the electrode connection unit (102) comprises a high-voltage electrode connection module, a ground electrode connection module, and an insulating layer, the insulating layer is filled between the two connection modules, the discharge electrode (103) comprises a high-voltage electrode and a ground electrode which are coaxially sleeved, the high-voltage electrode connection module is connected to the high-voltage electrode, and the ground electrode connection module is connected to the ground electrode; the explosion tube (104) comprises a metal wire; and the explosion tube (104) is connected to the discharge electrode (103); The coaxial cable (101) is used to transmit pulse current; The high-voltage electrode connection module is used to transmit the pulse current to the high-voltage electrode, and the grounding electrode connection module is used to provide a return circuit for the pulse current; the discharge electrode (103) is used to transmit the pulse current to the metal wire; The explosive tube (104) further comprises a metal foil and a shock wave propagation medium; the metal wire is connected to the high-voltage electrode and is used to generate a metal wire explosion using a pulse current; the metal foil is connected to the ground electrode and is used to provide a current loop; The shock wave propagation medium is used to transmit the shock wave generated by the explosion of the metal wire and fix the metal wire and the metal foil to achieve rock crushing.

2. The electrode structure according to claim 1, characterized in that: The discharge electrode is vertically inserted into the explosion tube. The explosion tube is damaged after the metal wire explodes. The discharge electrode is repeatedly used in conjunction with the explosion tube. Inserting the discharge electrode into the explosion tube is to replace the metal wire, which simplifies the process of replacing the metal wire.

3. The electrode structure according to claim 1, characterized in that: The high-voltage electrode is a column made of tungsten-copper alloy; the ground electrode is a tube made of brass; and insulating material is filled between the high-voltage electrode and the ground electrode.

4. The electrode structure according to claim 2, characterized in that: The insulating material of the discharge electrode is a cone at the head position, the bottom radius of which is consistent with the outer diameter of the ground electrode.

5. The electrode structure according to claim 1, characterized in that: The shock wave transmission medium is a cylinder with an open upper end.

6. The electrode structure according to claim 5, characterized in that: The metal wire is connected to the metal foil at the bottom end of the metal wire, a metal groove is designed at the first section of the metal wire, and the metal wire is vertically buried inside the cylinder, leaving only the metal groove.

7. The electrode structure according to claim 5 or 6, characterized in that: The metal foil is attached to the inner wall of the cylinder, and the inner diameter of the cylinder is consistent with the outer diameter of the discharge electrode.

8. The electrode structure according to claim 1, characterized in that: The coaxial cable adopts a multi-core wire structure.

Images