CN113286409A - Thermal plasma spray gun - Google Patents

Abstract

The object of the present invention is to provide a thermal plasma torch which provides a more stable arc while enabling free power regulation. This thermal plasma spray gun has first anode assembly and second anode assembly to two anode assemblies dispose independent first power and second power respectively, thereby when the thermal plasma spray gun used, the high temperature electric arc of production can also be inside the second anode assembly in first anode assembly is inside, has avoided single positive pole and the local high temperature electrode that leads to ablates, provides the life of thermal plasma spray gun. Specifically, the thermal plasma spray gun provided by the invention comprises a cathode assembly, a first anode assembly and a second anode assembly, wherein a first power supply is arranged between the cathode assembly and the first anode assembly, a second power supply is arranged between the cathode assembly and the second anode assembly, and the first power supply and the second power supply are mutually independent.

Description

Thermal plasma spray gun

Technical Field

The invention relates to the technical field of thermal plasma, in particular to a thermal plasma spray gun.

Background

The thermal plasma has the advantages of high temperature, high enthalpy, high energy density, high chemical activity, rich active particles, high reaction speed, large temperature gradient, quick start and stop and the like, the generated high temperature and high energy are superior to most of the existing high temperature technologies, and particularly, the thermal plasma technology provides a technical path for realizing 'harmlessness, reduction and recycling' for the treatment of hazardous wastes.

The core device of the thermal plasma technology in practical application is a thermal plasma spray gun, the thermal plasma spray gun heats gas by using high-temperature electric arc formed by discharge between a cathode and an anode, and the gas is heated to 1 x 10 by the electric arc after entering a compression section of an anode nozzle⁴And ionizing at a high temperature above K, entering the expansion section of the anode nozzle to expand and accelerate, and finally forming plasma jet. Thermal plasma technology is now widely used in the fields of machinery, chemical engineering, materials and aerospace. The main performance parameters of the thermal plasma torch depend on the temperature and the velocity distribution of the plasma jet, and the temperature and the velocity distribution of the plasma jet depend on the structural characteristics of the thermal plasma torch, so that the improvement of the structure of the thermal plasma torch to enable the structure to be more reasonable is a common concern in the field.

At present, a pair of electrodes, namely a cathode assembly and an anode assembly, is mostly adopted in a commonly used thermal plasma spray gun, and plasma jet is generated under the action of a direct current power supply. In the anode assembly, due to the interaction of the flow field and the electromagnetic field (namely the flow velocity of gas and the voltage of a power supply), a high-temperature electric arc moves continuously in the anode assembly, the energy of plasma changes continuously, so that jet flow is unstable, and meanwhile, the single-anode structure easily causes the high-temperature electric arc to be gathered in the anode to cause electrode ablation.

Moreover, the cathode and the anode of most thermal plasma spray guns are fixed in structure, and the distance between the cathode and the anode is also fixed, so that the input power of the spray gun is constant under the same working current.

Disclosure of Invention

In view of the drawbacks of the prior art, it is an object of the present invention to provide a thermal plasma torch capable of freely adjusting the power while maintaining a more stable arc.

The thermal plasma spray gun provided by the invention comprises a cathode assembly, a first anode assembly and a second anode assembly, wherein a first power supply is arranged between the cathode assembly and the first anode assembly, a second power supply is arranged between the cathode assembly and the second anode assembly, and the first power supply and the second power supply are mutually independent.

According to the technical scheme, firstly, the thermal plasma spray gun provided by the invention is provided with the first anode assembly and the second anode assembly, and the two anode assemblies are respectively provided with the independent first power supply and the independent second power supply, so that when the thermal plasma spray gun is used, a generated high-temperature electric arc can be arranged in the first anode assembly and the second anode assembly, the ablation of a local high-temperature electrode caused by a single anode is avoided, and the service life of the thermal plasma spray gun is prolonged.

Secondly, set up two anodes in the thermal plasma spray gun, compare and can only produce an electric arc in single anode, the setting of double anode can make the electric arc that thermal plasma spray gun produced longer, set up the power that mutually independent makes can dispose the power of different voltages according to the electric arc length difference that produces between negative pole subassembly and first positive pole subassembly, negative pole subassembly and the second positive pole subassembly to the double anode simultaneously for the electric arc that produces between negative pole subassembly and the second positive pole subassembly that negative pole subassembly and positive pole subassembly, especially the electric arc that produces are longer is also more stable.

Finally, the arrangement of the double anodes enables the power of the thermal plasma spray gun not to be single any more, further, the arrangement of the independent power supply can further expand the power adjustment range of the thermal plasma spray gun, and particularly, the electric arc generated by the cathode component and the first anode component is the first power of the thermal plasma spray gun provided by the invention; the cathode component and the second anode component generate electric arcs to provide second power for the thermal plasma spray gun; the simultaneous arcing of the cathode assembly with the first anode assembly and the cathode assembly with the second anode assembly provides the invention with a third power for the thermal plasma torch.

Preferably, the cathode assembly, the first anode assembly and the second anode assembly are sequentially and coaxially arranged at intervals.

According to the technical scheme, the electric arc that cathode assembly and first anode assembly produced, the electric arc that cathode assembly and second anode assembly produced is on same axis, thereby make, the first anode assembly that is close to each other with the cathode assembly can be used for striking, when hot plasma spray gun adjustment power, the electric arc can shift along the axis between first anode assembly and second anode assembly, and, thereby coaxial setting makes first electric arc and second electric arc can unite on same axis and produce the electric arc of higher temperature, each subassembly interval sets up and then can avoid cathode assembly and anode assembly short circuit and cause the damage to the spray gun, also can avoid first anode assembly and second anode assembly short circuit and cause the condition that electric arc length changes.

Preferably, the cathode assembly includes a cathode head capable of emitting electrons and a cathode sleeve disposed around the cathode head, the cathode sleeve communicating with the cathode cooling water passage and the first gas passage.

According to the technical scheme, the cathode head is coated with the cathode sleeve outside, so that electrons can be stably generated by the cathode head, the phenomenon that the stability of electric arcs generated by the thermal plasma spray gun is influenced due to the combination of external impurity ions and the electrons is avoided, and meanwhile, the gas passage is formed on the cathode sleeve, so that ionized gas (helium, argon, hydrogen and the like) can be continuously introduced into the cathode, the ionization process is continuously carried out, and stable electric arcs are formed. In addition, the temperature of the plasma arc is very high, and the cathode cooling water arranged on the cathode sleeve can reduce the temperature of the arc radiated on the cathode sleeve, thereby being convenient for operation and simultaneously prolonging the service life of the plasma spray gun.

Preferably, the first anode assembly and the second anode assembly are formed in a hollow sleeve structure, and a side wall of the first anode assembly and/or the second anode assembly is in communication with the anode cooling water passage.

According to the technical scheme, the first anode assembly and the second anode assembly are formed into a hollow sleeve structure, ionized gas is ionized under the action of high-temperature electric arc, ionized plasma can be sprayed outwards through the hollow parts of the first anode assembly and the second anode assembly, and therefore waste treatment operation is more facilitated by outwards spraying hot plasma jet of the hot plasma spray gun, an anode cooling water passage is also formed in the side wall of the hollow sleeve, the temperature on the anode sleeve can be reduced when the hot plasma spray gun is used, and the service life of the hot plasma spray gun is prolonged when technicians operate the hot plasma spray gun.

Preferably, the hollow portions of the first and second anode assemblies each have a necked down section in the axial direction. According to this technical scheme, fluid gets into convergent pipe diameter and can make the gas velocity of flow grow, and the fluid gets into rear portion heavy-calibre department with higher velocity of flow again this moment, because higher velocity of flow produces low pressure environment at the rear portion, the low pressure environment at rear portion more is favorable to promoting plasma and flows to the rear end by the front end of anode assembly to the velocity of flow when being favorable to further increasing plasma and outwards spouting.

Preferably, the first anode assembly and the second anode assembly are connected by an intermediate piece, the side wall of which is provided with additional gas passages.

According to the technical scheme, the first anode assembly and the second anode assembly are connected through the intermediate piece, the insulation between the first anode assembly and the second anode assembly is further guaranteed, the additional gas passage is arranged on the intermediate piece, ionized gas is provided for the interior of the cavity of the thermal plasma spray gun through the gas passage of the intermediate piece, and therefore the tail end of the electric arc is provided with sufficient ionized gas, and the electric arc is further stabilized.

Preferably, an additional cooling water passage is further provided on the intermediate member.

According to the technical scheme, the additional cooling water passage is arranged between the first anode assembly and the second anode assembly, so that the high-temperature electric arc is further cooled at the middle section of the thermal plasma spray gun.

Preferably, the cathode assembly further comprises an insulating gas distribution ring, the insulating gas distribution ring is formed at the end part of the first gas passage, is obliquely arranged between the cathode sleeve and the cathode head, and is provided with a plurality of through holes.

According to the technical scheme, the ionized gas can rotate along the inclined wall surface of the insulating gas-distributing ring; the insulating gas-separating ring is provided with a plurality of through holes, so that ionized gas can only enter the cavity of the thermal plasma spray gun through the through holes. Because the ionized gas rotates along the inclined wall surface of the insulating gas distribution ring, and the gas entering the cavity of the plasma torch from the through hole moves along different directions, the gas collides, the ionized effect of the ionized gas is enhanced, and in addition, the electric arc is compressed to the center under the action of the rotating gas, so that the electric arc is elongated, the plasma gas is fully heated, and the waste treatment effect of the torch is improved.

Preferably, the intermediate piece further comprises an additional insulating gas distribution ring, and the additional insulating gas distribution ring is obliquely arranged in the additional gas passage.

According to the technical scheme, the insulating gas distribution ring is also arranged in the additional gas passage, so that when gas enters the second anode assembly from the additional gas passage arranged in the intermediate piece, the gas can also rotate, a second arc between the cathode assembly and the second anode assembly is also stretched, and the arc length of the second anode assembly determines the longest arc length generated by the thermal plasma torch in the invention to a certain extent.

Drawings

FIG. 1 is a schematic diagram of a thermal plasma torch according to an embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of a thermal plasma torch according to an embodiment of the present invention;

FIG. 3 is a cross-sectional view of a second anode assembly of a thermal plasma torch according to an embodiment of the present invention;

fig. 4 is a sectional view of the structure of an intermediate member of the thermal plasma torch provided in the embodiment of the present invention;

fig. 5 is an enlarged view of a portion a of the thermal plasma torch according to the embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the following specific examples and the accompanying drawings. The present invention is not limited to the embodiments described below, and various modifications, changes, combinations, and improvements based on the technical idea of the present invention adopted within the knowledge of those skilled in the art are included in the scope of the present invention.

Fig. 1 is a schematic structural view of a thermal plasma torch according to the present embodiment. As shown in fig. 1, a cathode assembly 1, a first anode assembly 2 and a second anode assembly 3, wherein the cathode assembly 1 is electrically connected to the cathodes of the first power source 4 and the second power source 5, the first anode assembly 2 is electrically connected to the anode of the first power source 4, and the second anode assembly 3 is electrically connected to the anode of the second power source 5, so that when the first power source 4 and/or the second power source 5 are turned on, discharge is generated between the cathode assembly 1 and the first anode assembly 2 and/or the second anode assembly 3, and ionized gas inside the thermal plasma torch is ionized, thereby generating a high-temperature plasma arc, which can heat and melt external substances.

In particular, the stability of the arc when a thermal plasma torch is in use often determines the reliability of the torch in use and the lifetime of the torch. There are many factors that affect the stability of the arc, such as the type of ionized gas, the voltage and current level of the power supply, the length of the arc (i.e., the distance between the cathode and the anode, etc.).

Wherein the ionized gas may be N₂Gas or Ar gas, in particular, N₂The gas has high ion flame enthalpy and fast heat transfer, is beneficial to heating and melting external materials, but cannot be used for materials which are easy to generate nitridation reaction. The Ar gas has lower ionization potential, stable and easy ignition of generated electric arc and shorter arc flame, and has good protection effect, but the Ar gas is compared with N₂The heat content of the gas is low and the price is expensive.

The first power source 4 and the second power source 5 may be any power source device capable of providing suitable voltage and current, and as a preferred example, the first power source 4 and the second power source 5 are dc power sources, and the dc current is more favorable for improving the stability of the arc.

In addition, the length of electric arc needs to match with the voltage and the current size of the power, so set up first power 4 and second power 5 respectively to first anode subassembly 1 and second anode subassembly 2 to can set up suitable voltage and current according to the electric arc length (being the distance between negative pole and the positive pole) that produces between different anode subassemblies and the negative pole subassembly 1, be favorable to improving the stability of the electric arc that thermal plasma spray gun produced.

Through above mode, at first, first anode assembly 2 and second anode assembly 3 to two anode assemblies dispose independent first power 4 and second power 5 respectively, thereby when hot plasma spray gun used, the high temperature electric arc that produces can also can be inside second anode assembly 3 inside first anode assembly 2, has avoided single positive pole and the local high temperature electrode ablation that leads to, has improved hot plasma spray gun's life.

Secondly, set up two anodes in the thermal plasma spray gun, compare and can only produce an electric arc in single anode, the setting of double anode can make the electric arc that thermal plasma spray gun produced longer, set up the mutually independent power to double anode simultaneously and make and to dispose first power 4, the second power 5 of different voltages according to the electric arc length difference that produces between cathode assembly 1 and first anode assembly 2, cathode assembly 1 and the second anode assembly 3 for the electric arc that produces between cathode assembly 1 and the anode assembly, especially longer cathode assembly 1 of electric arc that produces and the second anode assembly 3 is more stable.

Finally, the arrangement of the double anodes enables the power of the thermal plasma torch to be no longer single, and further, the arrangement of the independent power supply can further expand the power adjustment range of the thermal plasma torch, specifically, in the embodiment, three kinds of power can be adjusted when the thermal plasma torch is used, an electric arc generated by the cathode assembly 1 and the first anode assembly 2 closer to the cathode assembly is the first power of the thermal plasma torch provided by the embodiment, and the electric arc generated by the thermal plasma torch is shorter at the power, and the temperature of the plasma jet is lower; the cathode assembly 1 and the second anode assembly 3 which is farther away generate longer electric arcs, which are the second power of the thermal plasma torch provided by the embodiment, and the electric arcs generated by the thermal plasma torch are longer under the second power, and the temperature of the plasma jet is medium; the cathode assembly 1 and the first anode assembly 2 and the cathode assembly 1 and the second anode assembly 3 simultaneously generate electric arcs, which provides the third power of the thermal plasma torch, the electric arcs generated by the thermal plasma torch are longer under the third power, and the temperature of the thermal plasma jet is the highest.

It should be noted that the specific structure of each component of the thermal plasma torch is not limited in the present invention, for example, the first anode assembly 2 may be a hollow circular ring structure in some embodiments, and in other embodiments, the first anode assembly 2 may also be a hollow sleeve structure with a necking section, and the structure of each component of the thermal plasma torch in the present invention may be simply replaced without departing from the spirit of the present invention, and the scope of the present invention is not exceeded.

Fig. 2 is a schematic cross-sectional view of a thermal plasma torch according to the present embodiment. In a preferred embodiment of the invention, seen in connection with fig. 2, the cathode assembly 1, the first anode assembly 2 and the second anode assembly 3 are sequentially spaced along an axis Y, when the thermal plasma spray gun works and the first power supply 4 and the second power supply 5 are both kept in an opening state, a first electric arc and a second electric arc are generated between the cathode component 1 and the first anode component 2 and between the cathode component and the second anode component 3, the first electric arc and the second electric arc are both superposed with the axis Y, at the moment, higher heat is generated in the middle of the coincident arcs, thereby generating plasma jet with higher temperature, stabilizing the arcs and simultaneously increasing the temperature of the thermal plasma jet, and in addition, when the thermal plasma spray gun works, the second power supply 5 is turned off for a period of time after being turned on, and when the first power supply 4 is turned on simultaneously, an electric arc is generated between the cathode assembly 1 and the second anode assembly 3, and then the falling point of the electric arc on the second anode assembly 3 is transferred to the first anode assembly 2 along the axis Y.

In addition, the interval sets up between negative pole subassembly 1, first positive pole subassembly 2 and the second positive pole subassembly 3 and can guarantee to keep insulating between each subassembly, can keep insulating between negative pole subassembly 1 and the first positive pole subassembly, avoid negative pole subassembly 1 and positive pole subassembly short circuit and cause the damage to the spray gun, also can keep insulating between first positive pole subassembly 2 and the second positive pole subassembly 3, avoid first positive pole subassembly 2 and the short circuit of second positive pole subassembly 3 and cause the condition that arc length changes. In particular, the gap may be filled by the insulating ring 7, and the insulating ring 7 has a simple structure and a connection function, so as to facilitate the integral installation of each component of the thermal plasma while ensuring the insulation, and of course, the gap may be filled by other insulating structures, for example, in some embodiments, an insulating ceramic is disposed at the connection of each component, or in other embodiments, an insulating gasket is added in the threaded connection between the components, which does not exceed the protection scope of the present invention.

Wherein, preferably, the cathode assembly 1 includes a cathode tap 11 capable of emitting electrons and a cathode sleeve 12 disposed around the cathode tap 11, in the thermal plasma spray gun, the cathode head 11 continuously emits electrons by means of thermionic emission effect during the use process, so that electrons can be continuously transmitted to the anode through electric arc conduction, preferably, thorium tungsten, cerium tungsten or lanthanum tungsten electrodes have the characteristics of high melting point (tungsten melting point 3410 +/-20 ℃), strong electron emission capability, low melting rate, corrosion resistance, good heat conduction and electric conductivity and the like, so adopt thorium tungsten, cerium tungsten or lanthanum tungsten material as negative pole head 11 material to the arcing performance of the negative pole subassembly 1 of thermal plasma spray gun is better, and the stability of electric arc is higher, and the electrode burnout rate is littleer, realizes the high efficiency start-up of thermal plasma spray gun, improves the stability of electric arc, extension cathode life.

The cathode sleeve 12 is wrapped around the cathode head 11, so as to block external impurities, and avoid the external impurities from being combined with electrons to affect the stability of the arc of the thermal plasma torch, further, after the cathode sleeve 12 wraps the cathode head 11, a gas passage needs to be arranged to provide ionized gas for the interior of the cavity of the thermal plasma torch, so that the cathode sleeve 12 is communicated with a first gas passage 121 for conveying ionized gas (helium, argon, hydrogen, etc.) to the interior of the thermal plasma torch, so that the ionization process is continuously performed, a stable arc is formed, further, the gas blowing direction of the first gas passage 121 is consistent with the direction of the cathode head 11 conveying electrons to the anode, the consistent direction does not mean two directions are overlapped strictly, only the ionized gas can be ionized in the arc on the axis Y after being blown close to the axis Y, so that the utilization rate of the ionized gas can be improved. In addition, when the thermal plasma spray gun works, the temperature of the cathode head 11 is very high, often can reach thousands of degrees or even tens of thousands of degrees, and the higher temperature is unfavorable for the cathode sleeve 12 and operators, so the cathode cooling water passage 122 is arranged on the cathode sleeve 12, the temperature of the arc radiation to the cathode sleeve 12 can be reduced through the cooling of the cooling water, the operation is convenient, and the service life of the thermal plasma spray gun is prolonged.

Preferably, the first anode assembly 2 and the second anode assembly 3 are formed in a hollow sleeve structure, the side walls of the first anode assembly 2 and/or the second anode assembly 3 are both made of pure copper material with good heat conduction and electric conduction, and the anode cooling water passage 221 is communicated with the side walls of the first anode assembly 2 and/or the second anode assembly 3, so as to rapidly dissipate heat of the first anode assembly 2 and/or the second anode assembly 3. In this embodiment, the first anode assembly 2 and the second anode assembly 3 are formed in a hollow sleeve structure, when the thermal plasma torch is operated, an arc can be formed in the hollow portion of the first anode assembly 2 or the second anode assembly 3, and the anode assemblies are formed in a hollow structure, thereby facilitating ionization of ionized gas in the hollow portions of the first anode assembly 2 and the second anode assembly 3 to form plasma, and further facilitating ejection of thermal plasma jet from the hollow portions of the first anode assembly 2 and the second anode assembly 3 to perform waste treatment operation.

Wherein, preferably, the hollow parts of the first anode assembly 2 and the second anode assembly 3 are provided with necking sections along the axial direction. In this embodiment, taking the first anode assembly 2 as an example, fig. 3 is a cross-sectional view of the second anode assembly 3, when the ionized gas flows into the necking section from the a region, the tube diameter gradually decreases, the gas flow rate increases, and a higher gas flow rate enters the B region through the necking section, and a higher flow rate is still maintained within a distance, at this time, a low-pressure environment is generated around the gas with a higher flow rate, and the pressure difference between the a region and the B region is favorable for pushing the plasma to further rapidly flow out from the a region to the B region, so that the plasma torch is favorable for ejecting the thermal plasma jet outwards to perform the waste treatment operation.

Among them, fig. 4 is a sectional view preferably showing the structure of the intermediate member 6 of the thermal plasma torch provided in the present embodiment. Referring to fig. 2 and 4, the first anode assembly 2 and the second anode assembly 3 are connected by an intermediate member 6, and an additional gas passage 662 is provided on a sidewall of the intermediate member 6. In the embodiment, the first anode assembly 2 and the second anode assembly 3 are in insulation connection through the intermediate member 6, so that the insulation between the first anode assembly 2 and the second anode assembly 3 is further ensured, and the installation stability of the thermal plasma spray gun is facilitated; in addition, the ionized gas density inside the second anode assembly 3 is increased by providing an additional gas passage 662 on the intermediate member 6, and further by introducing the ionized gas into the ionized gas inflow end of the second anode assembly 3 of the thermal plasma torch through the additional gas passage 662, preferably, as shown in fig. 4, the additional gas passage 662 may be a gas passage passing through one end of the intermediate member 6 and the other end of the intermediate member 6 connected with the second anode assembly 3, and further, the additional gas passage 662 is preferably a flat gas passage, which is more advantageous for the introduction of the ionized gas, and when the cathode assembly 1 and the second anode assembly 3 are energized to generate an arc, the ionized gas is introduced between the first anode assembly 2 and the second anode assembly 3 (i.e., the arc end), so that the arc may be further stabilized.

Further, it is preferable that an additional cooling water passage 661 is further provided to the intermediate member 6. An additional cooling water passage 661 is provided between the first anode assembly 2 and the second anode assembly 3 to further cool the high temperature arc at the middle section of the thermal plasma torch.

Among them, fig. 5 is preferably an enlarged view of a portion a of the thermal plasma torch provided in the present embodiment. Referring to fig. 2 and 5, the insulating gas-distributing ring 13 is disposed between the cathode sleeve 12 and the cathode head 11, and a plurality of through holes 131 are formed on the insulating gas-distributing ring 13.

In the present embodiment, the ionized gas is introduced into the cavity of the thermal plasma torch through the first gas passage 121, and then rotates along the inclined wall surface of the insulating gas distribution ring 13; and the insulating gas-distributing ring 13 is also provided with a plurality of through holes 131 along the radial direction, so that ionized gas can only enter the cavity of the thermal plasma spray gun through the through holes 131. Because the ionized gas rotates along the inclined wall surface of the insulating gas distribution ring 13, and the gas entering the inner cavity of the plasma torch from the through hole 131 moves along different directions, so that collision occurs, the ionization effect of the gas is enhanced, in addition, the electric arc is compressed towards the center under the action of the rotated gas, so that the electric arc is elongated, the plasma gas is fully heated, and the waste treatment effect of the torch is improved.

In particular, as seen in fig. 2 and 4, an additional insulating gas distribution ring 663 is further provided in the additional gas passage 662, and when gas enters the second anode assembly 3 through the additional gas passage 662 provided in the intermediate member 6, rotation and collision can be generated, so that the second arc generated between the cathode assembly 1 and the second anode assembly 3 is also elongated, and the distance between the cathode assembly 1 and the second anode assembly 3 is further increased, so that the length of the second arc determines the longest length of the arc generated by the thermal plasma torch in the present invention to some extent, and therefore, the arc length of the thermal plasma torch can be further increased by providing the additional insulating gas distribution ring 663 in the additional gas passage 662.

Those of skill in the art will appreciate that the specific features of the various embodiments may be adaptively separated or combined. Such splitting or combining of specific features does not cause the technical solutions to deviate from the principle of the present invention, and therefore, the technical solutions after splitting or combining will fall within the protection scope of the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

So far, the technical solutions of the present invention have been described in connection with the embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present invention is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the invention, and the technical scheme after the changes or substitutions can fall into the protection scope of the invention.

Description of the reference numerals

1-a cathode assembly;

11-cathode head;

12-a cathode sleeve;

121-a first gas passage;

122-cathode cooling water path;

13-insulating gas-separating ring;

131-a through hole;

2-a first anode assembly;

221, 331-Anode Cooling Water passage

3-a second anode assembly;

4-a first power supply;

5-a second power supply;

6-an intermediate piece;

661-additional cooling water passage;

662-additional gas passages;

663-additional insulating gas-distributing ring;

7-insulating ring.

Claims (9)

1. The utility model provides a thermal plasma spray gun, its characterized in that includes negative pole subassembly, first positive pole subassembly and second positive pole subassembly, the negative pole subassembly with be provided with first power between the first positive pole subassembly, the negative pole subassembly with be provided with the second power between the second positive pole subassembly, first power and second power mutually independent.

2. A thermal plasma torch according to claim 1 wherein the cathode assembly, first anode assembly and second anode assembly are coaxially spaced in sequence.

3. The thermal plasma torch according to claim 2 wherein said cathode assembly includes a cathode head capable of emitting electrons and a cathode sleeve disposed around said cathode head, said cathode sleeve communicating with a cathode cooling water passage and a first gas passage.

4. A thermal plasma torch according to claim 3 wherein the first and second anode assemblies are formed as hollow sleeve structures, the side walls of the first and/or second anode assemblies being in communication with an anode cooling water passage.

5. A thermal plasma torch according to claim 4 wherein the hollows of the first and second anode assemblies each have a necked down section in the axial direction.

6. A thermal plasma torch according to any one of claim 3, wherein said first anode assembly and said second anode assembly are connected by an intermediate member,

an additional gas passage is provided on the side wall of the intermediate member.

7. A thermal plasma torch according to claim 6 wherein additional cooling water passages are provided in said intermediate member.

8. The thermal plasma torch according to claim 6, wherein the cathode assembly further comprises an insulating gas distribution ring formed at the first gas passage end, disposed obliquely between the cathode sleeve and the cathode head, and having a plurality of through holes formed thereon.

9. A thermal plasma torch according to claim 8 wherein said intermediate piece further comprises an additional insulating gas distribution ring, said additional insulating gas distribution ring being obliquely disposed in said additional gas passage.

Images