A plasma torch

Abstract

The utility model discloses a kind of plasma spray gun, including the rear end of spray gun middle section, the front end of spray gun middle section, electric arc nozzle, front locking ring, protective gas spiral flow distribution distributor and powder nozzle fixing frame;Further include: the rear end of spray gun middle section, the rear end of spray gun middle section is equipped with air inlet hole, backwater hole and protective gas air inlet hole.This plasma spray gun connects protective gas cover directly with spray gun middle section, realizes integrated processing, is convenient to dismount and install, reduces unnecessary pipeline setting;Protective gas spiral flow distribution distributor makes protective gas distribution more uniform and stable, simultaneously play the role of rear locking ring, reduce gun body redundancy design;Electric arc nozzle's S type cooling water flow guide mode plays better cooling effect;Front locking ring and powder nozzle fixing frame ensure that powder is transported stably in spraying process, and powder trajectory does not change.

Description

Technical Field

[0001] This utility model relates to the technical field of plasma spraying equipment, specifically a plasma spray gun. Background Technology

[0002] Atmospheric plasma spraying technology has been widely used in the preparation of metal and ceramic coatings due to its advantages such as high efficiency and low cost. However, when spraying in an open environment, active materials (such as yttrium fluoride) react violently with oxygen, causing the coating composition to deviate from the design value, which directly affects the key properties of the coating such as corrosion resistance and bonding strength. It is difficult to spray easily oxidized powders and obtain a high-purity coating on conventional plasma spraying equipment. However, by using plasma spray gun equipment, an inert gas environment can be provided during the spraying process to reduce powder oxidation and to achieve controllable adjustment of arc energy density.

[0003] An existing publication, CN203002541U, entitled "An Atmosphere Protective Cover for an Atmospheric Plasma Spray Gun," describes a protective cover comprising a left cover, a right cover, and locking bolts. The left and right covers are geometrically symmetrical. They are connected by the locking bolts to form a semi-sealed inner cavity. Each cover has a protective gas connection port machined onto a conical surface of each cover, positioned symmetrically relative to the geometric center line of the cover. This protective cover prevents powder particles from oxidizing during the atmospheric plasma spraying process, resulting in a high-quality coating.

[0004] However, the aforementioned atmosphere protection cover adopts a split structure and is connected by bolts, which is cumbersome to disassemble. It relies on symmetrical air inlets for air intake and has no special gas flow guidance design, which reduces the oxidation effect to a small extent. At the same time, it is a fixed-size symmetrical cavity, which cannot achieve controllable adjustment of arc energy density, thus limiting its applicability.

[0005] To address the aforementioned issues, we have implemented an innovative design based on the existing plasma spray gun structure. Utility Model Content

[0006] The purpose of this utility model is to provide a plasma spray gun to solve the problems mentioned in the background art, namely that the existing atmosphere protection cover adopts a split structure and is connected by bolts, which is cumbersome to disassemble, relies on symmetrical air inlets for air intake, has no special gas flow guidance design, has little effect on reducing oxidation, and is a fixed-size symmetrical cavity, which cannot achieve controllable adjustment of arc energy density and has a narrow range of applications.

[0007] To achieve the above objectives, this utility model provides the following technical solution: a plasma spray gun, comprising a rear end of a spray gun middle section, a front end of a spray gun middle section, an arc nozzle, a front locking ring, a protective gas spiral distributor, and a powder nozzle fixing bracket; further comprising: a rear end of the spray gun middle section, wherein the rear end of the spray gun middle section is provided with an air inlet, a water return hole, and a protective gas inlet; a front end of the spray gun middle section, wherein the front end of the spray gun middle section is provided with a water outlet and a protective gas outlet connected to the rear end of the spray gun middle section; an arc nozzle, wherein the arc nozzle integrates an S-shaped cooling water guide device to form a spiral cooling water path; a front locking ring, wherein the front locking ring is connected to the powder nozzle fixing bracket; a protective gas spiral distributor, wherein the protective gas spiral distributor has protective gas spiral outlet holes opened at equal angles on its inner side, and the protective gas spiral distributor is fixed to the front end of the spray gun middle section by a thread connected to the spray gun middle section; and a powder nozzle fixing bracket, wherein the powder nozzle fixing bracket is connected to the front locking ring.

[0008] Preferably, the S-shaped cooling water guiding device is made of tungsten copper alloy, with a guiding groove width of 1-3mm and a depth of 2-5mm.

[0009] Preferably, the outer periphery of the front locking ring has six sets of centrally symmetrical positioning holes, and the inner side of the powder nozzle fixing bracket has six sets of centrally symmetrical positioning through holes, with each positioning hole corresponding to the positioning through hole, and the bracket is fastened with screws.

[0010] Preferably, the powder nozzle holder has a 90-degree powder nozzle holder on one side and an 80-degree powder nozzle holder on the other side.

[0011] Preferably, the protective gas spiral distributor is connected to the restraint-type threaded protective gas cover via a thread that connects to the protective gas cover.

[0012] Preferably, the protective gas spiral distributor is connected to the open threaded protective gas cover via a thread that connects to the protective gas cover.

[0013] Compared with the prior art, the beneficial effects of this utility model are: the plasma spray gun:

[0014] The protective gas shroud is directly connected to the middle section of the spray gun, achieving integrated processing, facilitating disassembly and installation, and reducing unnecessary piping. The protective gas spiral distributor ensures more uniform and stable distribution of the protective gas, while also acting as a rear locking ring, reducing redundant gun design. The S-shaped cooling water guide of the arc nozzle provides better cooling. The front locking ring and powder nozzle holder ensure stable powder delivery and a consistent powder trajectory during spraying. The restrained threaded connection of the protective gas shroud reduces oxidation of easily oxidized powders under high-temperature conditions and hydrogen reaction, and increases arc energy density. The open threaded connection of the protective gas shroud reduces dust particles on the component surface and cools the components in an inert gas environment. This significantly improves the adaptability of atmospheric plasma spraying technology to different powders and operating conditions. Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural diagram of the rear end of the spray gun of this utility model.

[0016] Figure 2 This is a three-dimensional structural diagram of the front end of the spray gun of this utility model;

[0017] Figure 3 This is a three-dimensional structural diagram of the arc nozzle of this utility model;

[0018] Figure 4 This is a three-dimensional structural diagram of the front locking ring of this utility model;

[0019] Figure 5 This is a three-dimensional structural diagram of the protective gas spiral flow distributor of this utility model;

[0020] Figure 6 This is a three-dimensional structural diagram of the powder nozzle fixing bracket of this utility model;

[0021] Figure 7 This is a three-dimensional structural diagram of the restraint-type threaded connection protective gas cover of this utility model;

[0022] Figure 8 This is a three-dimensional structural diagram of the open-type threaded connection protective gas cover of this utility model;

[0023] Figure 9 This is a three-dimensional structural diagram of the spray gun electrode of this utility model.

[0024] In the diagram: 1. Rear end of the spray gun middle section; 101. Air inlet; 102. Water return hole; 103. Protective gas inlet; 2. Front end of the spray gun middle section; 201. Water outlet connected to the rear end of the spray gun middle section; 202. Protective gas outlet; 3. Arc nozzle; 301. S-shaped cooling water guide device; 4. Front locking ring; 401. Positioning hole; 5. Protective gas spiral distributor; 501. Protective gas spiral outlet; 502. Thread connected to the protective gas cover; 503. Thread connected to the spray gun middle section; 6. Powder nozzle holder; 601. Positioning through hole; 602. 90-degree powder nozzle holder; 603. 80-degree powder nozzle holder; 7. Restrained threaded connection protective gas cover; 8. Open threaded connection protective gas cover; 9. Spray gun electrode. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] Please see Figures 1-9 This utility model provides a technical solution: a plasma spray gun, comprising:

[0027] Example 1: As Figures 1-8 The present invention provides a technical solution: a plasma spray gun, comprising a rear end 1 of the spray gun's middle section, a front end 2 of the spray gun's middle section, an arc nozzle 3, a front locking ring 4, a protective gas spiral distributor 5, and a powder nozzle holder 6; further comprising: the rear end 1 of the spray gun's middle section, which is provided with an air inlet 101, a water return hole 102, and a protective gas inlet 103; the front end 2 of the spray gun's middle section, which is provided with a water outlet 201 and a protective gas outlet 202 connected to the rear end of the spray gun's middle section; and the arc nozzle 3, which integrates an S-shaped cooling water guide. Device 301 forms a spiral cooling water path; front locking ring 4 is connected to powder nozzle fixing bracket 6 and also to the front section of the spray gun; protective gas spiral distributor 5 has protective gas spiral outlet holes 501 opened at equal angles on its inner side, and the protective gas spiral distributor 5 is fixed to the front end 2 of the middle section of the spray gun through a thread 503 connected to the middle section of the spray gun; nozzle fixing bracket 6 is connected to the front locking ring 4; wherein, there are two outlet holes 201, return holes 102 and protective gas inlet holes 103 connected to the rear end of the middle section of the spray gun.

[0028] In this invention, the other parts of the spray gun, such as the front and rear sections of the spray gun, are not improvements of this invention, but belong to existing designs, so their structures will not be described in detail.

[0029] The S-type cooling water guide device 301 is made of tungsten copper alloy, with a guide groove width of 1-3mm and a depth of 2-5mm. An arc nozzle 3 is provided at the rear end 1 of the middle section of the spray gun. The rear end 1 of the middle section of the spray gun and the arc nozzle 3 are connected through the front section of the spray gun, which is existing technology. The front locking ring 4 has six sets of centrally symmetrical positioning holes 401 on its periphery. The powder nozzle fixing bracket 6 has six sets of centrally symmetrical positioning through holes 601 on its inner side. The positioning holes 401 and the positioning through holes 601 correspond one-to-one and are fastened with screws. The nozzle fixing bracket 6 has a 90-degree powder nozzle fixing bracket 602 on one side and an 80-degree powder nozzle fixing bracket 603 on the other side. The protective gas spiral distributor 5 is connected to the restraint-type threaded protective gas cover 7 through a thread 502 connected to the protective gas cover.

[0030] The rear end 1 of the spray gun's middle section is equipped with a water inlet pipe and a protective gas pipe. Both water and protective gas circuits are processed inside the rear end 1 of the spray gun's middle section. Water enters the front end 2 of the spray gun's middle section through the water inlet at the rear end. The cooling water cools the arc nozzle 3. It circulates in a closed loop at the front end of the spray gun, returns to the rear end through the middle section, and then enters the spray gun electrode 9 for cooling. The protective gas enters the porous protective gas spiral distributor 5 through the front end 2 of the spray gun's middle section. This porous protective gas spiral distributor 5 is tightly connected to the front end 2 of the spray gun's middle section via threads and a sealing ring, ensuring no leakage of the protective gas. The protective gas is then distributed evenly through the porous protective gas spiral distributor. The spiral of device 5 enters the protective gas shroud, providing protection. This porous protective gas spiral distributor also acts as a locking mechanism, primarily connecting the front and middle sections of the spray gun to prevent leakage. The front locking ring 4 locks the front section of the spray gun to the arc nozzle 3. The front locking ring 4 also features an innovative design, with six centrally symmetrical positioning holes 401 machined around its periphery. The nozzle holder 6 also has six centrally symmetrical positioning through holes 601 machined. The positioning through holes 601 correspond to the positioning holes 401 and are secured with screws. This prevents positional changes in the flame due to powder trajectory variations during spraying, ensuring the stability of the spray flame during the spraying process.

[0031] The cooling water guiding device of the arc nozzle 3 abandons the conventional straight guiding method and adopts an S-shaped guiding method, which can increase the contact area with the cooling water, improve the cooling effect, and extend the service life of the arc nozzle 3. The threaded connection protective gas cover is divided into two types: restraint type and open type. It is connected to the multi-hole protective gas spiral distributor 5 through threads. The restraint type threaded connection protective gas cover 7 plays the role of creating an inert gas environment to prevent the oxidation of easily oxidized powder under the reaction of hydrogen in a high-temperature environment during the spraying process. At the same time, due to the gas compression, it plays a restraining role on the flame and plays a role in increasing the energy density of the arc.

[0032] Example 2: Figures 1-7 , Figure 9 The present invention provides a technical solution: a plasma spray gun, which discloses that: a protective gas spiral distributor 5 is connected to an open threaded protective gas cover 8 through a thread 502 connected to the protective gas cover;

[0033] This structure features an open threaded connection protective gas cover 8, which is connected to a porous protective gas spiral distributor 5 via a thread 502. The open threaded connection protective gas cover 8 can reduce oxidation, but its effect is slightly less than that of a restrained type. At the same time, it can blow away dust particles from the surface of the component, reduce dust particles on the surface of the component, and cool the component.

[0034] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0035] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A plasma spray gun, comprising a rear end (1) of the middle section of the spray gun, a front end (2) of the middle section of the spray gun, an arc nozzle (3), a front locking ring (4), a protective gas spiral distributor (5), and a powder nozzle holder (6); characterized in that, Also includes: The rear end (1) of the middle section of the spray gun is provided with an air inlet (101), a water return hole (102) and a protective gas inlet (103). The front end (2) of the middle section of the spray gun is provided with a water outlet (201) and a protective gas outlet (202) connected to the rear end of the middle section of the spray gun. An electric arc nozzle (3) is provided, which integrates an S-shaped cooling water guide device (301) to form a spiral cooling water path. A front locking ring (4) is connected to a powder nozzle holder (6); A protective gas spiral distributor (5) is provided with protective gas spiral outlet holes (501) at equal angles on the inner side of the protective gas spiral distributor (5), and the protective gas spiral distributor (5) is fixed to the front end (2) of the middle section of the spray gun through a thread (503) connected to the middle section of the spray gun. Powder nozzle holder (6), which is connected to the front locking ring (4).

2. The plasma spray gun according to claim 1, characterized in that: The S-type cooling water guide device (301) is made of tungsten copper alloy, with a guide groove width of 1-3mm and a depth of 2-5mm.

3. A plasma spray gun according to claim 1, characterized in that: The front locking ring (4) has six sets of centrally symmetrical positioning holes (401) on its periphery, and the powder nozzle fixing bracket (6) has six sets of centrally symmetrical positioning through holes (601) on its inner side. The positioning holes (401) and positioning through holes (601) correspond one-to-one and are fastened with screws.

4. A plasma spray gun according to claim 1, characterized in that: The powder nozzle holder (6) has a 90-degree powder nozzle holder (602) on one side and an 80-degree powder nozzle holder (603) on the other side.

5. A plasma spray gun according to claim 1, characterized in that: The protective gas spiral distributor (5) is connected to the restraint-type threaded protective gas cover (7) via a thread (502) connected to the protective gas cover.

6. A plasma spray gun according to claim 1, characterized in that: The protective gas spiral distributor (5) is connected to the open threaded protective gas cover (8) via a thread (502) that is connected to the protective gas cover.

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