Plasma atomization device for preparing metal powder through multi-stage cooling

Abstract

The invention relates to a plasma atomization device for preparing metal powder through multi-stage cooling, and relates to the technical field of metal powder manufacturing, the plasma atomization device comprises an atomization chamber and a cooling pipe arranged on the atomization chamber, the atomization chamber is used for plasma atomization of metal, the cooling pipe is communicated with the atomization chamber, and the atomization chamber is communicated with the cooling pipe. The cooling pipe comprises an indirect cooling section and a direct cooling section, the indirect cooling section is arranged at the end, close to the atomizing chamber, of the cooling pipe, the direct cooling section is arranged at the end, away from the atomizing chamber, of the cooling pipe, the cooling pipe is provided with an expansion pipe used for storing a cooling medium, and the expansion pipe is arranged around the indirect cooling section. The cooling pipe is provided with a cooling air pipe, the cooling air pipe is communicated with the direct cooling section, and the cooling air pipe is used for filling a cooling medium into the direct cooling section of the cooling pipe. The method has the effect of improving the production quality of the metal powder.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metal powder manufacturing, in particular to a multi-stage cooling plasma atomization device for preparing metal powder. BACKGROUND

[0002] When producing metal powder, plasma atomization can be used for production. Plasma atomization is a preparation technology that evaporates metal raw materials into steam through high-temperature plasma, and then condenses the steam into ultra-fine powder through inert gas.

[0003] Currently, the cooling of metal droplets / vapor is usually achieved through single direct contact cooling or indirect contact cooling with carrier gas. Direct contact cooling is not conducive to the formation of uniform and stable metal nuclei due to low gas phase environment temperature and low concentration of metal droplets / vapor after dilution by carrier gas. Indirect contact cooling produces metal powder with different core sizes. Although indirect contact cooling can avoid the above problems, the flow rate, temperature of carrier gas near the inner wall and near the center area, and the concentration of metal droplets / vapor are not uniform, resulting in inconsistent condensation nucleation and settling time of metal droplets / vapor, and inconsistent overall cooling effect. There is a great limitation in obtaining metal powder with a narrow particle size distribution. The overall size of the metal powder produced by direct cooling is not uniform, and the overall quality of the produced metal powder needs to be improved. SUMMARY

[0004] In order to improve the production quality of metal powder, the present application provides a multi-stage cooling plasma atomization device for preparing metal powder.

[0005] The multi-stage cooling plasma atomization device for preparing metal powder provided by the present application adopts the following technical solution: A multi-stage cooling plasma atomization device for preparing metal powder, comprising an atomization chamber and a cooling pipe arranged on the atomization chamber, the atomization chamber being used for plasma atomization of metal, the cooling pipe being in communication with the atomization chamber, the cooling pipe comprising an indirect cooling section and a direct cooling section, the indirect cooling section being arranged at one end of the cooling pipe close to the atomization chamber, the direct cooling section being arranged at one end of the cooling pipe away from the atomization chamber, the cooling pipe being provided with an enlarged pipe for storing cooling medium, the enlarged pipe being arranged around the indirect cooling section, the cooling pipe being provided with a cooling gas pipe, the cooling gas pipe being in communication with the direct cooling section, the cooling gas pipe being used for filling cooling medium into the direct cooling section of the cooling pipe.

[0006] By adopting the technical scheme, the cooling of the indirect cooling section is realized by means of non-contact radiation heat transfer of the cooling medium in the enlarged pipe to the metal vapor entering the cooling pipe, the metal vapor nucleation stage adopts indirect cooling, the metal vapor concentration is not diluted, the metal nucleation rate is high, and high productivity can be ensured. The high productivity can be ensured. The direct cooling section is cooled by the direct contact between the cooling medium filled in the cooling gas pipe and the metal vapor, the cooling medium and the metal vapor are fully mixed for cooling, the cooling effect of the whole metal vapor is ensured, the metal vapor is indirectly cooled by the reactor, the metal vapor nucleation and deposition are realized, and then the metal vapor and the metal nucleus enter the direct cooling section and are directly contacted with the cooling medium for cooling, thereby overcoming the defects of single indirect cooling and single direct cooling, improving the cooling effect, improving the stability of the metal powder nucleation size, improving the stability of the whole size of the metal powder, and thereby improving the quality of the metal powder.

[0007] As preferred, a flow guide impeller is arranged in rotation in the cooling pipe, a driving motor is arranged in the cooling pipe, a rotating shaft of the driving motor is connected with the flow guide impeller, a filter plate for filtering metal powder is arranged in the cooling pipe at the direct cooling section, the flow guide impeller is arranged at a side of the filter plate away from the indirect cooling section, a powder recovery pipe is arranged in the cooling pipe and communicates with the direct cooling section, the powder recovery pipe is arranged at a side of the filter plate close to the indirect cooling section, and a gas outlet pipe is arranged in the cooling pipe and communicates with the direct cooling section, the gas outlet pipe is arranged at a side of the flow guide impeller away from the filter plate.

[0008] By adopting the technical scheme, the driving motor drives the flow guide impeller to rotate, and guides the gas to flow in the cooling pipe. The cooled metal powder is blocked by the filter plate and falls into the powder recovery pipe under the pushing of the gas. The gas enters the gas outlet pipe after passing through the filter plate and is discharged or recovered. The operation is simple and convenient, and the cooling operation is facilitated.

[0009] As preferred, the enlarged pipe is annular, and an inner wall of the enlarged pipe is connected. The enlarged pipe is sleeved on the cooling pipe. A stirring ring is arranged in rotation in the enlarged pipe. The stirring ring is sleeved on the cooling pipe in rotation. The stirring ring is provided with a plurality of stirring rods. A first transmission assembly is arranged between the stirring ring and the driving motor. The first transmission assembly is used for driving the stirring ring to rotate according to the rotation of the rotating shaft of the driving motor.

[0010] By adopting the technical scheme, the driving motor drives the stirring ring to rotate through the first transmission assembly, so as to drive the stirring rods to rotate in the enlarged pipe for stirring, thereby improving the flowability of the cooling medium in the enlarged pipe, reducing the possibility that the cooling medium close to the cooling pipe does not flow after being heated, reducing the cooling effect, and ensuring the cooling quality.

[0011] Preferably, the rotating inside the enlarged pipe is provided with an auxiliary ring, the auxiliary ring is sleeved on the cooling pipe, the auxiliary ring is provided with a plurality of auxiliary rods, the auxiliary ring is provided with a connecting rod, and the connecting rod is connected with the stirring ring.

[0012] By adopting the above technical scheme, the connecting rod drives the auxiliary ring to rotate with the stirring ring, thereby driving the auxiliary rod to rotate in the enlarged pipe for stirring, improving the stirring effect, and improving the flowability of the cooling medium in the enlarged pipe, thereby ensuring the cooling effect.

[0013] Preferably, the first transmission assembly comprises a first transmission gear, a second transmission gear, a transmission rod, a third transmission gear and a fourth transmission gear, the first transmission gear is rotatably arranged on the cooling pipe and connected with the rotating shaft of the driving motor, the transmission rod is rotatably arranged on the cooling pipe and inserted into the inside of the enlarged pipe, the second transmission gear is connected with the transmission rod and meshes with the first transmission gear, the third transmission gear and the fourth transmission gear are both rotatably arranged in the inside of the enlarged pipe and mesh with each other, the third transmission gear is connected with the transmission rod, and the fourth transmission gear is rotatably sleeved on the cooling pipe and connected with the stirring ring.

[0014] By adopting the above technical scheme, the driving motor drives the first transmission gear to rotate, thereby driving the second transmission gear to rotate, the second transmission gear drives the transmission rod to rotate to drive the third transmission gear to rotate, and the third transmission gear drives the fourth transmission gear to rotate to drive the stirring ring to rotate, thereby achieving transmission.

[0015] Preferably, the cooling pipe is provided with a protective cover, and the first transmission gear and the second transmission gear are covered in the protective cover.

[0016] By adopting the above technical scheme, the first transmission gear and the second transmission gear are covered in the protective cover, thereby reducing the possibility of damage caused by external collision, improving the durability, and reducing the risk of finger injury caused by being wrapped between the first transmission gear and the second transmission gear.

[0017] Preferably, the cooling pipe is provided with an assembly block, the transmission rod is rotatably arranged through the assembly block, the filter plate is rotatably provided with a cleaning rod, and a second transmission assembly is arranged between the cleaning rod and the transmission rod, the second transmission assembly is used to drive the cleaning rod to rotate according to the rotation of the transmission rod.

[0018] By adopting the above technical scheme, the assembly block is used to improve the stability of the rotation of the transmission rod, and the rotation of the transmission rod drives the cleaning rod to rotate through the second transmission assembly, thereby cleaning the surface of the filter plate and pushing the metal particles into the powder recovery pipe, reducing the probability of metal powder accumulation on the filter plate to block the holes of the filter plate for filtering, and improving the filtering stability.

[0019] Preferably, the second transmission assembly comprises a first transmission sprocket, a second transmission sprocket and a transmission chain, the assembly block is provided with a first transmission groove, the filter plate is provided with a second transmission groove, the first transmission groove is communicated with the second transmission groove, the second transmission groove is not communicated with the hole of the filter plate, the first transmission sprocket is rotatably arranged in the first transmission groove and sleeved on the transmission rod, the second transmission sprocket is rotatably arranged in the second transmission groove and connected with the cleaning rod, and the transmission chain is engaged and sleeved on the first transmission sprocket and the second transmission sprocket.

[0020] By adopting the above technical scheme, the transmission rod drives the first transmission gear to rotate, thereby driving the second transmission sprocket to rotate through the transmission chain, and driving the cleaning rod to rotate, thereby realizing transmission.

[0021] Preferably, the atomization chamber is provided with a plasma torch inserted into the interior, the atomization chamber is provided with a feeding port, and the output end of the plasma torch is arranged directly below the feeding port.

[0022] By adopting the above technical scheme, the plasma torch is used to realize the plasma atomization of the metal, and the operation is simple and convenient, and the atomization is stable and high in quality.

[0023] In summary, the present application has at least one of the following beneficial technical effects: 1. By arranging the atomization chamber, the cooling pipe, the direct cooling section, the indirect cooling section, the expansion pipe and the cooling gas pipe, the metal vapor atomized in the atomization chamber is first indirectly cooled by the cooling medium in the expansion pipe without contact in the indirect cooling section after entering the cooling pipe, so that the metal vapor is not diluted when cooled and nucleated, and then the nucleated metal vapor enters the direct cooling section to contact the cooling medium filled in the cooling gas pipe, so that the metal vapor is fully contacted with the cooling medium, the overall cooling effect is improved, and the overall size consistency of the metal powder and the internal metal nucleus size consistency are improved, and the cooling quality is improved. 2. By arranging the flow guide impeller, the driving motor, the filter plate, the gas outlet pipe and the powder recovery pipe, the driving motor drives the flow guide impeller to rotate, the driving motor drives the flow guide impeller to rotate, thereby driving the gas in the cooling pipe to flow, and driving the cooled metal particles to flow, the metal particles are blocked by the filter plate and fall into the powder recovery pipe, and the gas flows through the filter plate and enters the gas outlet pipe, thereby improving the stability of the cooling and recovery. 3. By arranging the stirring ring, the stirring rod, the first transmission gear, the second transmission gear, the transmission rod, the third transmission gear and the fourth transmission gear, the driving motor drives the first transmission gear to rotate, the meshing transmission drives the second transmission gear to rotate, and then drives the third transmission gear to rotate through the transmission rod, thereby driving the stirring ring to rotate through the fourth transmission gear, and driving the stirring rod to rotate in the expansion pipe for stirring, thereby improving the flowability of the stirring medium in the expansion pipe and reducing the probability of reducing the cooling effect of the cooling medium after the internal cooling medium is heated. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a whole schematic diagram of a multi-stage cooling plasma atomization device for preparing metal powder provided by an embodiment of the present application.

[0025] Figure 2 is a sectional view for embodying the internal structure of the atomization chamber.

[0026] Figure 3 is a sectional view for embodying the internal structure of the cooling pipe.

[0027] Figure 4 is Figure 3 is an enlarged view of the A area in FIG. 6.

[0028] BRIEF DESCRIPTION OF DRAWINGS: 1, atomization chamber; 11, inlet; 12, plasma torch; 2, cooling pipe; 21, indirect cooling section; 22, direct cooling section; 23, cooling gas pipe; 24, powder recovery pipe; 25, exhaust pipe; 26, assembly block; 261, first transmission groove; 27, protective cover; 3, expansion pipe; 31, stirring ring; 311, stirring rod; 32, auxiliary ring; 321, auxiliary rod; 322, connecting rod; 4, flow guide impeller; 41, driving motor; 42, filter plate; 421, cleaning rod; 422, second transmission groove; 5, first transmission assembly; 51, first transmission gear; 52, second transmission gear; 53, transmission rod; 54, third transmission gear; 55, fourth transmission gear; 6, second transmission assembly; 61, first transmission sprocket; 62, second transmission sprocket; 63, transmission chain. DETAILED DESCRIPTION

[0029] The following will be described in detail in combination with the accompanying drawings. Figures 1-4 The present application will be further described in detail.

[0030] An embodiment of the present application discloses a multi-stage cooling plasma atomization device for preparing metal powder. Referring to Figures 1 to 3The device comprises a hollow atomizing chamber 1 and a cooling pipe 2 fixed on the outer wall of the atomizing chamber 1, the atomizing chamber 1 is used for plasma atomization of metal, and the cooling pipe 2 is communicated with the inside of the atomizing chamber 1 and is used for cooling and forming of the metal vapor after atomization. The cooling pipe 2 is divided into an indirect cooling section 21 and a direct cooling section 22, the indirect cooling section 21 is arranged at one end of the cooling pipe 2 close to the atomizing chamber 1, and the direct cooling section 22 is arranged at one end of the cooling pipe 2 away from the atomizing chamber 1. The cooling pipe 2 is provided with an enlarged pipe 3 for storing cooling medium, the enlarged pipe 3 is annular, the inside of the enlarged pipe 3 is communicated with the inner wall of the enlarged pipe 3, and the enlarged pipe 3 is arranged around the indirect cooling section 21 so that the cooling medium filled in the inside of the enlarged pipe 3 can directly contact the outer wall of the indirect cooling section 21 of the cooling pipe 2. The cooling pipe 2 is provided with a cooling gas pipe 23 communicated with the direct cooling section 22, and the cooling medium is injected into the direct cooling section 22 of the cooling pipe 2 through the cooling gas pipe 23. The atomizing chamber 1 is provided with a feeding port 11 communicated with the inside at the top, and a plasma torch 12 is arranged in the atomizing chamber 1, and the output end of the plasma torch 12 is located directly below the feeding port 11 so as to perform plasma atomization. The metal vapor is firstly indirectly cooled in the indirect cooling section 21, the possibility of large size deviation of nucleation is reduced by reducing the dilution of the cooling medium in the nucleation period, and then the metal vapor is directly cooled in the direct cooling section 22, the possibility of large size deviation of the metal powder is reduced by reducing the insufficient cooling, and the overall size consistency of the metal powder is improved. In other embodiments, a plurality of carrier gas pipes can be arranged around the cooling pipe 2 on the outer wall of the atomizing chamber 1, and a small amount of inert gas is added into the inside of the atomizing chamber 1 as carrier gas to better drive the metal vapor into the cooling pipe.

[0031] For convenient use, with reference to Figure 2 and Figure 3 , a flow guide impeller 4 is arranged in the cooling pipe 2 at the direct cooling section 22, a driving motor 41 is fixedly arranged at one end of the cooling pipe 2 away from the atomizing chamber 1, the rotating shaft of the driving motor 41 is inserted into the cooling pipe 2 and is fixedly connected with the flow guide impeller 4 in a coaxial manner, and the flow guide impeller 4 is used to drive the gas in the cooling pipe 2 to flow after rotation. A filter plate 42 is fixedly arranged in the cooling pipe 2, the filter plate 42 is arranged in the direct cooling section 22 and separates the inside of the cooling pipe 2, a plurality of filter holes for filtering are arranged in the filter plate 42, and a filter film for filtering and separating gas and metal powder is arranged on the surface of the filter plate 42 close to the atomizing chamber 1. The cooling pipe 2 is provided with a powder recovery pipe 24 communicated with the direct cooling section 22 and an air outlet pipe 25, the powder recovery pipe 24 is arranged on the side of the filter plate 42 close to the atomizing chamber 1, and the air outlet pipe 25 is arranged on the side of the flow guide impeller 4 away from the filter plate 42. The flow guide impeller 4 drives the metal vapor and the cooling medium filled in the cooling gas pipe 23 to flow, which is convenient to use.

[0032] In order to improve the cooling effect, with reference to Figure 2 and Figure 3, the stirring ring 31 is rotationally arranged in the expansion pipe 3 and is sleeved on the cooling pipe 2, a plurality of stirring rods 311 are fixedly arranged on the outer side wall of the stirring ring 31 away from the cooling pipe 2, two auxiliary rings 32 are rotationally arranged in the expansion pipe 3 and are sleeved on the cooling pipe 2, a plurality of auxiliary rods 321 are fixedly arranged on the outer side wall of the auxiliary ring 32 away from the cooling pipe 2, the auxiliary ring 32 is fixedly provided with a plurality of connecting rods 322, and the connecting rod 322 connects the stirring ring 31 and each auxiliary ring 32. The first transmission assembly 5 is arranged between the stirring ring 31 and the driving motor 41 and is used for driving the stirring ring 31 to rotate according to the rotation of the rotating shaft of the driving motor 41. The driving motor 41 drives the stirring ring 31 and the auxiliary ring 32 to rotate through the first transmission assembly 5, so that the cooling medium in the expansion pipe 3 is driven to flow in a stirring manner, the probability of reducing the cooling effect of the cooling medium after the internal cooling medium is warmed is reduced, and the cooling effect is improved.

[0033] For convenient use, referring to Figure 3 and Figure 4 , the first transmission assembly 5 includes a first transmission gear 51, a second transmission gear 52, a transmission rod 53, a third transmission gear 54 and a fourth transmission gear 55, the cooling pipe 2 is detachably provided with a protective cover 27 away from the atomizing chamber 1, the first transmission gear 51 and the second transmission gear 52 are rotationally arranged in the protective cover 27 and are meshed with each other, the first transmission gear 51 is coaxially and fixedly connected with the rotating shaft of the driving motor 41, the third transmission gear 54 and the fourth transmission gear 55 are rotationally arranged in the expansion pipe 3 and are meshed with each other, and the fourth transmission gear 55 is rotationally sleeved on the cooling pipe 2 and is fixedly connected with the stirring ring 31. The cooling pipe 2 is fixedly provided with an assembly block 26 connected with the protective cover 27, the transmission rod 53 is rotationally arranged on the assembly block 26, and the two ends of the transmission rod 53 are respectively inserted into the protective cover 27 and the expansion pipe 3, and the two ends of the transmission rod 53 are respectively fixedly connected with the second transmission gear 52 and the third transmission gear 54. The driving motor 41 drives the first transmission gear 51 to rotate, drives the second transmission gear 52 to rotate after meshing, drives the third transmission gear 54 to rotate through the transmission rod 53, and then drives the stirring ring 31 to rotate through the meshing fourth transmission gear 55, so that transmission is realized without the need for additional operation, which is convenient to use.

[0034] In order to reduce the cleaning frequency, referring to Figure 3 and Figure 4The cleaning rod 421 is arranged on the surface of the filter plate 42 close to the atomization chamber 1 and is used for cleaning the surface of the filter film. The second transmission assembly 6 is arranged between the cleaning rod 421 and the transmission rod 53 and is used for driving the cleaning rod 421 to rotate according to the rotation of the transmission rod 53. The second transmission assembly 6 comprises a first transmission sprocket 61, a second transmission sprocket 62 and a transmission chain 63. The first transmission groove 261 is arranged in the assembly block 26. The filter plate 42 is provided with a second transmission groove 422 which is not communicated with the filter holes of the filter plate 42 and is communicated with the first transmission groove 261 through the cooling pipe 2. The first transmission sprocket 61 is rotatably arranged in the first transmission groove 261 and is fixedly sleeved on the transmission rod 53. The second transmission sprocket 62 is rotatably arranged in the second transmission groove 422 and is coaxially fixedly connected with the rotating shaft of the cleaning rod 421. The transmission chain 63 is arranged in the first transmission groove 261 and the second transmission groove 422 and is meshingly sleeved on the first transmission sprocket 61 and the second transmission sprocket 62. The driving motor 41 drives the cleaning rod 421 to rotate through the second transmission assembly 6 to clean the filter film, reduces the probability of metal powder blocking the filter film and reduces the frequency of disassembling and cleaning the filter plate 42 and the filter film.

[0035] The implementation principle of the embodiment of the application is as follows: the metal material is communicated into the atomization chamber 1 through the pipeline connected to the inlet 11 and is subjected to plasma atomization by the plasma torch 12. Meanwhile, the driving motor 41 is started to drive the flow guide impeller 4 to rotate, guiding the metal vapor into the cooling pipe 2 and flowing. The metal vapor is first subjected to indirect cooling in the indirect cooling section 21. The cooling medium in the enlarged pipe 3 is replaced through the pipeline connected to the inlet pipe on the enlarged pipe 3. The metal vapor is first subjected to indirect cooling mainly by heat radiation. The possibility of the nucleation size deviation being large due to the dilution of the cooling medium in the nucleation period is reduced. Then, the metal vapor is subjected to direct cooling in the direct cooling section 22. The cooling medium and the cooling gas pipe 23 are communicated to the direct cooling section 22 of the cooling pipe 2 to directly cool the metal vapor after nucleation by the cooling gas. The possibility of the overall size deviation of the metal powder being large due to insufficient cooling is reduced, and the overall size consistency of the metal powder is improved. Meanwhile, under the rotation of the flow guide impeller 4, the metal powder flows with the gas until being separated by the filter plate 42. The metal powder enters the powder recovery pipe 24 for recovery, and the gas is recovered through the gas outlet pipe 25.

[0036] The above are the preferred embodiments of the application, which do not limit the protection scope of the application. Any equivalent changes made according to the structure, shape and principle of the application should be covered by the protection scope of the application.

Claims

1. A multi-stage cooling plasma atomization apparatus for producing metal powder, characterized by: The device includes an atomizing chamber (1) and a cooling pipe (2) disposed on the atomizing chamber (1). The atomizing chamber (1) is used for plasma atomization of metals. The cooling pipe (2) is connected to the atomizing chamber (1). The cooling pipe (2) includes an indirect cooling section (21) and a direct cooling section (22). The indirect cooling section (21) is disposed at one end of the cooling pipe (2) near the atomizing chamber (1). The direct cooling section (22) is disposed at one end of the cooling pipe (2) away from the atomizing chamber (1). The cooling pipe (2) is provided with an expansion pipe (3) for storing cooling medium. The expansion pipe (3) is disposed around the indirect cooling section (21). The cooling pipe (2) is provided with a cooling air pipe (23). The cooling air pipe (23) is connected to the direct cooling section (22). The cooling air pipe (23) is used to fill the direct cooling section (22) of the cooling pipe (2) with cooling medium.

2. The multi-stage cooling plasma atomization device for producing metal powder according to claim 1, wherein: The cooling pipe (2) is equipped with a rotatable impeller (4), and the cooling pipe (2) is equipped with a drive motor (41). The shaft of the drive motor (41) is connected to the impeller (4). The cooling pipe (2) is equipped with a filter plate (42) for filtering metal powder in the direct cooling section (22). The impeller (4) is located on the side of the filter plate (42) away from the indirect cooling section (21). The cooling pipe (2) is equipped with a powder recovery pipe (24) connected to the direct cooling section (22). The powder recovery pipe (24) is located on the side of the filter plate (42) close to the indirect cooling section (21). The cooling pipe (2) is equipped with an exhaust pipe (25) connected to the direct cooling section (22). The exhaust pipe (25) is located on the side of the impeller (4) away from the filter plate (42).

3. The plasma atomization device for preparing metal powder with multi-stage cooling according to claim 2, characterized in that: The expansion tube (3) is annular and its interior is connected to the inner wall. The expansion tube (3) is sleeved on the cooling tube (2). A stirring ring (31) is rotatably arranged inside the expansion tube (3). The stirring ring (31) is rotatably sleeved on the cooling tube (2). The stirring ring (31) is provided with a plurality of stirring rods (311). A first transmission assembly (5) is provided between the stirring ring (31) and the drive motor (41). The first transmission assembly (5) is used to drive the stirring ring (31) to rotate according to the rotation of the shaft of the drive motor (41).

4. The plasma atomization device for preparing metal powder by multi-stage cooling according to claim 3, characterized in that: An auxiliary ring (32) is rotatably arranged inside the expansion tube (3). The auxiliary ring (32) is sleeved on the cooling tube (2). The auxiliary ring (32) is provided with a plurality of auxiliary rods (321). The auxiliary ring (32) is provided with a connecting rod (322). The connecting rod (322) is connected to the stirring ring (31).

5. The plasma atomization device for preparing metal powder through multi-stage cooling according to claim 3, characterized in that: The first transmission assembly (5) includes a first transmission gear (51), a second transmission gear (52), a transmission rod (53), a third transmission gear (54), and a fourth transmission gear (55). The first transmission gear (51) is rotatably mounted on the cooling pipe (2) and connected to the shaft of the drive motor (41). The transmission rod (53) is rotatably mounted on the cooling pipe (2) and inserted into the expansion pipe (3). The second transmission gear (52) is connected to the transmission rod (53) and meshes with the first transmission gear (51). The third transmission gear (54) and the fourth transmission gear (55) are both rotatably mounted inside the expansion pipe (3) and mesh with each other. The third transmission gear (54) is connected to the transmission rod (53). The fourth transmission gear (55) is rotatably mounted on the cooling pipe (2) and connected to the stirring ring (31).

6. The plasma atomization device for preparing metal powder through multi-stage cooling according to claim 5, characterized in that: The cooling pipe (2) is provided with a protective cover (27), which covers the first transmission gear (51) and the second transmission gear (52).

7. The plasma atomization device for preparing metal powder through multi-stage cooling according to claim 5, characterized in that: The cooling pipe (2) is provided with an assembly block (26), the transmission rod (53) rotates through the assembly block (26), the filter plate (42) is rotatably provided with a cleaning rod (421), and a second transmission component (6) is provided between the cleaning rod (421) and the transmission rod (53). The second transmission component (6) is used to drive the cleaning rod (421) to rotate according to the rotation of the transmission rod (53).

8. The plasma atomization device for preparing metal powder by multi-stage cooling according to claim 7, characterized in that: The second transmission assembly (6) includes a first transmission sprocket (61), a second transmission sprocket (62), and a transmission chain (63). The assembly block (26) is provided with a first transmission groove (261), and the filter plate (42) is provided with a second transmission groove (422). The first transmission groove (261) is connected to the second transmission groove (422), and the second transmission groove (422) is not connected to the holes of the filter plate (42). The first transmission sprocket (61) is rotatably disposed in the first transmission groove (261) and sleeved on the transmission rod (53). The second transmission sprocket (62) is rotatably disposed in the second transmission groove (422) and connected to the cleaning rod (421). The transmission chain (63) is meshed and sleeved on the first transmission sprocket (61) and the second transmission sprocket (62).

9. The plasma atomization device for preparing metal powder by multi-stage cooling according to claim 1, characterized in that: The atomizing chamber (1) is equipped with a plasma torch (12) inserted inside, and the atomizing chamber (1) is equipped with a feed inlet (11). The output end of the plasma torch (12) is located directly below the feed inlet (11).

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