Metal powder production line and production process

Abstract

The application discloses a metal powder production line and a production process, and relates to the technical field of metal powder manufacturing. The metal powder production line comprises a powder manufacturing device; the powder manufacturing device comprises an atomization bin, and an injection channel and a gas injection channel are arranged at the top of the inner cavity of the atomization bin; inert gas sprayed through the gas injection channel can impact the metal melt discharged through the injection channel to form a mixed jet; an expansion assembly is arranged outside the junction position of the liquid film part and the liquid drop part in a circumferential manner. The expansion assembly can rotate and increase the taper of the liquid drop part, so that the number (i.e. the density is reduced) of metal droplets and / or metal powder contained in the liquid drop part per unit volume is reduced, the probability of mutual impact of the metal droplets / metal powder is reduced, the probability and the number of satellite powder formation are reduced, and the rate of defective products is obviously reduced.

Description

Technical Field

[0001] This invention relates to the field of metal powder manufacturing technology, specifically to metal powder production lines and manufacturing processes. Background Technology

[0002] Metal powders (such as copper-gold powder, pearlescent powder, etc.) can be used in additive manufacturing as well as in coatings (such as inks, paints, etc.).

[0003] Atomization powdering is a commonly used metal powder manufacturing technology. It utilizes a high-pressure airflow to impact molten metal to obtain metal droplets, which are then cooled and solidified to produce metal powder. Satellite powder is a defective product produced by atomization powdering technology, which is generated by the contact and adhesion of two metal droplets or one metal droplet with one metal powder.

[0004] The Chinese invention patent "Pre-film Swirl Diffusion Gas Atomization Equipment" (Publication No.: CN117840442B) discloses a technical solution to reduce satellite powder by impacting metal droplets / metal powder from bottom to top. It increases the taper (and volume) of the mixed jet to a certain extent. However, the distance between metal droplets / metal powder in a local area decreases after being impacted, which increases the probability of them contacting each other and generating satellite powder. Therefore, the defect rate is reduced and then increased again. Summary of the Invention

[0005] In order to overcome the problem in the above-mentioned background technology that "the form of applying impact force cannot significantly reduce the probability of satellite powder formation", the present invention provides a metal powder production line and production process.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: A metal powder production line includes powder manufacturing equipment; the powder manufacturing equipment includes an atomizing chamber, the top of which is provided with a feeding channel and a jetting channel; inert gas ejected through the jetting channel can impact molten metal discharged through the feeding channel to form a mixed jet, the mixed jet including a liquid film portion and a droplet portion; an expansion component is circumferentially fitted on the outer side of the junction of the liquid film portion and the droplet portion, the expansion component being used to increase the taper of the droplet portion to reduce the number of metal droplets and / or metal powder contained in a unit volume of the droplet portion.

[0007] As a further optimization of the present invention, the expansion component includes an expansion ring; the expansion ring includes an upper ring body, a lower ring body, and a first blade; the first blade is installed in a circumferential array between the upper ring body and the lower ring body; a first gap is provided between the expansion ring and the mixing jet; the expansion ring is rotatable to reduce the air pressure in the first gap.

[0008] As a further optimization of the present invention, when the expansion ring rotates, a low-pressure air band and a high-pressure air band are formed on the inner and outer sides respectively; the expansion assembly also includes an annular cover, which is adapted to cover the outer periphery of the expansion ring and is used to limit the high-pressure air band.

[0009] As a further optimization of the present invention, the expansion component further includes an air intake structure; the top end of the air intake structure is connected to the high-pressure gas belt and is used to discharge the inert gas in the high-pressure gas belt to increase the taper increment of the droplet portion.

[0010] As a further optimization of the present invention, a sorting column is provided in the middle of the atomizing chamber; a first annular groove is provided between the outer wall of the sorting column and the inner wall of the atomizing chamber, and an inverted conical groove is provided inside the sorting column; The content of satellite powder at the outer edge of the bottom of the mixed jet is lower than the content of satellite powder at the middle of the bottom of the mixed jet; the inverted conical groove is used to guide the metal powder falling through the middle of the mixed jet; The air intake structure can guide a portion of the internal inert gas to below the bottom opening of the inverted conical groove to form a sorting airflow; the sorting airflow is used to sort satellite powder in the metal powder discharged through the inverted conical groove.

[0011] As a further optimization of the present invention, the air intake structure delivers the sorting airflow through a zigzag tube; the upper part of the zigzag tube is inserted into the sorting column to transmit vibration energy to the sorting column.

[0012] As a further optimization of the present invention, the lower part of the atomizing chamber is provided with an impact module, which is used to crush the satellite powder obtained by the sorting airflow; the impact module includes a support block and a hollow impact roller; the support block is provided with a guide vertical hole, and the impact roller is installed eccentrically in the guide vertical hole, which can squeeze the satellite powder; the air intake structure can guide part of the inert gas inside to the impact module to drive the impact roller to rotate.

[0013] As a further optimization of the present invention, a kinetic energy converter is provided at the top of the guide vertical hole; the kinetic energy converter includes a fixed cylinder coaxially arranged with the impact roller; the inert gas discharged through the suction structure can flow through the fixed cylinder and the impact roller, driving the impact roller to rotate; a second impeller connected to the impact roller is provided inside the fixed cylinder, and / or a spiral fin is provided inside the impact roller.

[0014] As a further optimization of the present invention, the support block is provided with an upper convex cavity with a bottom opening. The upper convex cavity is connected to a heat exchanger through a return horizontal pipe. The heat exchanger is connected to a second air pump through a first return pipe. The second air pump is connected to the jet channel through a second return pipe. The sorting column and the impact module can block the inert gas discharged through the air intake structure to avoid the formation of an upward airflow in the atomizing chamber cavity for impacting the mixed jet.

[0015] The metal powder production process employs a metal powder production line to manufacture metal powder. The steps include: S1, the inert gas impacts the molten metal to obtain the mixed jet; S2, the expansion ring rotates, forming a low-pressure gas band within the first gap, driving the droplet portion to expand outwards; simultaneously, the suction structure draws inert gas from the high-pressure gas band; S3, metal powder at the outer edge of the bottom of the mixed jet falls and penetrates the first annular groove; metal powder at the middle of the bottom of the mixed jet falls and penetrates the first annular groove; S4, the sorting airflow separates satellite powder, which is then crushed by the impact module to obtain metal powder. During this process, the suction structure diverts internal airflow to below the sorting column and within the impact module to form the sorting airflow and drive the impact roller to rotate.

[0016] In summary, the present invention has at least one of the following advantages: (1) The present invention has a simple structure and reliable function. The expansion component is used to increase the taper of the droplet part to reduce the number of metal droplets and / or metal powder contained in the droplet part per unit volume (i.e., the density is reduced). This reduces the probability of metal droplets contacting each other, the probability of metal droplets contacting each other and metal powders, and the probability of (incompletely cured) metal powders contacting and colliding with each other, thereby reducing the probability and quantity of satellite powder formation and reducing the defect rate.

[0017] (2) In order to increase the taper of the droplet, the present invention applies a tensile force to it, while conventional technology usually applies an impact force; the difference is that the impact force will cause the spacing between metal particles / metal droplets in the local area of ​​the (droplet) to decrease, thus increasing the probability and quantity of satellite powder formation in that area; however, the tensile force successfully avoids such problems, thus having a lower defect rate.

[0018] (3) When the annular cover covers the expansion ring, it can partially block the high-pressure gas belt and keep it under pressure (reducing the flow with the inert gas on the outside). After connecting the intake structure, the high-pressure gas belt can be depressurized quickly and significantly (if the annular cover is not set, the nearby inert gas will flow into the high-pressure gas belt to compensate for it, so the gas pressure cannot be reduced significantly). This reduces the gas pressure of the low-pressure gas belt, thereby applying a greater pulling force to the droplet part, which makes the taper of the droplet part larger and the probability of satellite powder formation lower.

[0019] (4) In order to generate a sufficient pressure difference to drive the droplet part to expand outward, the airflow in the suction structure needs to have a high flow rate, that is, the inert gas at this position has a large kinetic energy. On the one hand, to avoid wasting kinetic energy, and on the other hand, to avoid the formation of an upward airflow that impacts the droplet part in the first ring groove, the kinetic energy is quickly consumed by the sorting airflow, vibration transmission and crushing module, which ensures that the optimized defect rate will not deteriorate again.

[0020] (5) The sorting column and the impact module can block the inert gas discharged through the air intake structure to avoid the formation of an upward airflow in the atomization chamber for impacting the mixing jet, and will not hinder the falling of qualified metal powder.

[0021] (6) The vibration of the sorting column is driven by the Z-shaped tube, which avoids the problem of metal powder adhering to the sorting column, and thus avoids the problem of increased impurity rate when switching the manufacturing type of metal powder.

[0022] (7) Single particles of powder are obtained by impacting satellite powder using the crushing module, which further reduces the defect rate.

[0023] (8) Before impacting the satellite powder, the qualified metal powder (i.e., single-particle powder) is removed by the sorting column and sorting airflow, which avoids the problem of damage (e.g., breakage) caused by the impact of the crushing module on the single-particle powder, thereby increasing the proportion of spherical metal powder and improving product quality; and since the single-particle powder will not fall into the interior of the impact module (i.e., into the guide vertical hole), the problem of multiple single-particle powders covering the satellite powder and acting as a buffer to resist the impact will not occur, thus improving the crushing reliability and efficiency of the satellite powder; and it can avoid the problem of the impact module being blocked by a large amount of metal powder; and it reduces the amount of kinetic energy required by the impact module.

[0024] (9) The airflow of inert gas discharged from the impact module flows downward, which reduces the risk of it flowing upward through the second annular groove (directly), further reduces the risk of it flowing upward through the first annular groove, and further reduces the risk of it impacting the droplet. Attached Figure Description

[0025] The present application will be further explained below with reference to the accompanying drawings: Figure 1 This is a front view of the overall structure of the present invention. Figure 2 A front view diagram showing the location of the expansion components; Figure 3 A frontal view of the state where the opening angle of the droplet is increased by the expansion ring; Figure 4 This is a schematic diagram of the expansion ring structure viewed from a top angle. Figure 5 A top-down view showing the first blade's deployment configuration; Figure 6 A top-view diagram showing the formation positions of the high-pressure and low-pressure air belts; Figure 7 Front view of the vertical section for setting the position of the annular cover; Figure 8 A front view diagram of the annular cover covering the expansion ring in a vertical section; Figure 9 Top view of the location of the first motor; Figure 10 This is a front view of the vertical section of the sorting column and impact module structure. Figure 11 This is a top view diagram showing the position and structure of the first spring; Figure 12 Top view of the impact roller eccentric setting configuration; Figure 13 This is a front view diagram of the vertical section of the impact roller structure; Figure 14 A front view diagram showing the positions of the first and second crosses; Figure 15 This is a partial sectional view of the rotary cylinder.

[0026] Explanation of reference numerals in the attached figures: In the picture, 1. Atomizing chamber; 101. Storage chamber; 102. Discharge valve; 11. Injection channel; 12. Air jet channel; 13. Laval nozzle; 131. Diagonal strut; 14. Expansion assembly; 141. Expansion ring; 1411. Upper ring body; 1412. Lower ring body; 14121. Bevel gear ring; 1413. First blade; 14131. Low-pressure air belt; 14132. High-pressure air belt; 142. Annular cover; 1421. First bearing; 1422. Second bearing; 143. Intake horizontal pipe; 144. First motor; 1441. First output shaft; 145. First gear; 146. First air pump; 1461. First air delivery pipe; 1462. Second air delivery pipe; 147. Z-shaped pipe; 1471. First air valve; 148. Diverter pipe; 2. Smelting bin; 3. Molten metal; 31. Mixed jet; 311. Liquid film section; 312. Droplet section; 3120. First gap; 4. Sorting column; 41. First annular groove; 42. Inverted conical groove; 43. First guide cone surface; 44. First spring; 5. Impact module; 51. Support block; 511. Guide vertical hole; 512. Upper concave cavity; 513. Second annular groove; 52. Impact roller; 521. Main shaft; 5211. Support ring; 522. First inner support rod; 523. Rotary cylinder; 5231. Guide cone plate; 524. Spiral fins; 53. Kinetic energy converter; 531. Fixed cylinder; 5311. First fixed rod; 5312. First cross; 532. Second impeller; 54. Second motor; 541. Second output shaft; 542. Bottom support horizontal plate; 543. Second cross; 55. Outer support fixed rod; 6. Heat exchanger; 61. Return horizontal tube; 7. Second air pump; 71. First return pipe; 72. Second return pipe. Detailed Implementation

[0027] Based on the above-described structural features of this application, the implementation methods of this application will be further described as follows: The metals are divided into single-particle powder and satellite powder (formed by several single-particle powders adhering to each other). Among them, single-particle powder is qualified metal powder, while satellite powder is substandard.

[0028] Reference Figures 1-2 This embodiment provides a metal powder production line, including powder manufacturing equipment. The powder manufacturing equipment includes a vertically placed atomizing chamber 1. The top of the inner cavity of the atomizing chamber 1 (specifically, inside the top plate) is provided with a material injection channel 11 and a jet injection channel 12. A melting chamber 2 is provided above the atomizing chamber 1 (for example, it is fixedly connected by bolts, and a heat insulation layer is provided between the two). The top end of the material injection channel 11 is connected to the bottom end of the inner cavity of the melting chamber 2, and the bottom end of the material injection channel 11 is connected to the top end of the inner cavity of the atomizing chamber 1. The melting chamber 2 is used to heat (e.g., electrode heating, induction heating, flame heating, etc.) the solid metal inside it to obtain a highly fluid metal melt 3. The metal fluid flows through the material injection channel 11 and enters the inner cavity of the atomizing chamber 1 under its own weight and / or air pressure. The inert gas ejected through the jet channel 12 impacts the molten metal 3 discharged through the injection channel 11 to form a (conical) mixed jet 31. The mixed jet 31 includes a liquid film portion 311 and a droplet portion 312. The liquid film portion 311 is positioned above the droplet portion 312, which is conical and frustum-shaped. The molten metal 3 within the liquid film portion 311 forms a scattering band. The molten metal 3 within the droplet portion 312 is in the form of droplets (i.e., molten metal droplets, which later cool and solidify to form metal powder).

[0029] Reference Figures 2-3 An expansion component 14 is circumferentially sleeved on the outer side of the junction between the liquid film portion 311 and the droplet portion 312. The expansion component 14 is used to increase the taper of the droplet portion 312 (specifically, the increase in the opening angle, which increases the volume of the droplet portion 312) to reduce the number of metal droplets and / or metal powder contained in a unit volume of the droplet portion 312 (i.e., the density decreases). This reduces the probability of metal droplets contacting each other, the probability of metal droplets contacting metal powder, and the probability of (incompletely cured) metal powder contacting each other, thereby reducing the probability and quantity of satellite powder formation and reducing the defect rate.

[0030] Reference Figure 1 In conventional technology, the opening angle of the mixed jet 31 is R (this angle is related to the injection angle of the inert gas and the fluidity of the molten metal 3).

[0031] Reference Figure 2 In this patent, by using the expansion component 14 to drive the bottom of the liquid film portion 311 and the top of the droplet portion 312 to expand outward, the opening angle R2 of the droplet portion 312 can be greater than the opening angle R of the mixing jet 31 (in the conventional art). Since the attractive force generated by the expansion component 14 is locally conducted to the liquid film portion 311, the opening angle R1 of the liquid film portion 311 will be slightly greater than the opening angle R of the mixing jet 31 (in the conventional art). Furthermore, since the attractive force generated by the expansion component 14 acts on the end (i.e., the bottom) of the liquid film portion 311 and the beginning (i.e., the top) of the droplet portion 312, R2 > R1.

[0032] Reference Figure 1 and Figure 2 A (vertically positioned) Laval nozzle 13 is provided below the injection channel and above the liquid film section 311. When the inert gas and molten metal 3 mix and pass through the inner cavity of the Laval nozzle 13 at high speed, a conical mixed jet 31 is formed. The Laval nozzle 13 is fixedly connected to the top surface of the inner cavity of the atomizing chamber 1 by several diagonal braces 131; the diagonal braces 131 are arranged in a circumferential array on the outer periphery of the Laval nozzle 13; one end of the diagonal brace 131 is fixedly connected to the top surface of the inner cavity of the atomizing chamber 1 (e.g., by welding or by heat-resistant bolts), and the other end is fixedly connected to the outer wall of the Laval nozzle 13 (e.g., by welding or by heat-resistant bolts).

[0033] Reference Figure 3 and Figure 4The expansion assembly 14 includes an expansion ring 141 (coaxially arranged with the Laval nozzle 13); the expansion ring 141 includes an upper ring body 1411, a lower ring body 1412, and a first blade 1413; the upper ring body 1411 is annular, and the lower ring body 1412 is annular and coaxially arranged with the upper ring body 1411. The upper ring body 1411 is located above the lower ring body 1412, and a plurality of first blades 1413 are arranged in a circumferential array between the upper ring body 1411 and the lower ring body 1412 (centered on the axis of the upper ring body 1411); the top end of the first blade 1413 is fixedly connected to the upper ring body 1411 (e.g., by welding or by heat-resistant bolts), and the bottom end is fixedly connected to the lower ring body 1412 (e.g., by welding or by heat-resistant bolts).

[0034] Reference Figure 3 , Figure 4 and Figure 5 The first blade 1413 is inclined to fit the outer wall of the droplet portion 312. Several first blades 1413 are inclined in a frustum shape, so that when they rotate, they can apply a uniform, upward-sloping pulling force to the frustum-shaped droplet portion 312 (the direction of the pulling force is perpendicular to the outer wall of the droplet portion 312), thereby enabling the droplet portion 312 to expand outward evenly and improve product quality (preventing satellite powder from forming at the bottom outer edge of the droplet portion 312 and falling into the storage bin as impurities).

[0035] Reference Figure 2 A first gap 3120 is provided between the expansion ring 141 and the mixed jet 31; the expansion ring 141 can rotate (with the axis of the Laval nozzle 13 as the center) to reduce the air pressure in the first gap 3120, thereby pulling the droplet part 312 to expand outward.

[0036] Reference Figure 2 , Figure 4 and Figure 6 The first blade 1413 is disposed on one side inside the expansion ring 141 to capture gas molecules inside the expansion ring 141; the other side of the first blade 1413 is disposed on the outside of the expansion ring 141 to expel the captured gas molecules, so as to form a pressure difference between the inside and outside of the expansion ring 141, that is, a low-pressure gas band 14131 (annular) and a high-pressure gas band 14132 (annular) are formed on the inside and outside of the expansion ring 141, respectively.

[0037] Reference Figure 6 , Figure 7 and Figure 8When the expansion ring 141 rotates, a low-pressure gas band 14131 and a high-pressure gas band 14132 are formed on the inner and outer sides respectively. The expansion assembly 14 also includes an annular cover 142, which is adapted to cover the outer periphery of the expansion ring 141 to block the outer, top, and lower edges of the high-pressure gas band 14132, thereby limiting the high-pressure gas band 14132. This is used for subsequent suction operations to rapidly reduce its gas pressure, thereby rapidly and significantly reducing the gas pressure of the low-pressure gas band 14131, further reducing the probability of satellite powder formation.

[0038] Reference Figure 8 The upper ring 1411 is rotatably connected to the top surface of the inner cavity of the annular cover 142 via a first bearing 1421, which is sleeved and installed on the outer side wall of the upper ring 1411; the lower ring 1412 is rotatably connected to the bottom surface of the inner cavity of the annular cover 142 via a second bearing 1422, which is sleeved and installed on the outer side wall of the lower ring 1412; thereby improving the rotational stability and speed of the expansion ring 141.

[0039] Reference Figure 8 The expansion assembly 14 also includes a first motor 144, the housing of which is fixedly connected to the outer wall of the annular cover 142 (e.g., by heat-resistant bolts). The first output shaft 1441 of the first motor 144 is inserted into a through hole in the side wall of the annular cover 142. A first gear 145 is fixedly mounted on the outer periphery of the first output shaft 1441 (e.g., by heat-resistant bolts). A bevel gear ring 14121 is provided at the outer edge of the top surface of the lower ring 1412. The first gear 145 (e.g., a bevel gear) meshes with the bevel gear ring 14121. The first motor 144 can drive the bevel gear ring 14121 (and the entire expansion ring 141) to rotate through the first gear 145.

[0040] Reference Figure 7 and Figure 9 The annular cover 142 is circular; its cross-section is C-shaped, used to cover the expansion ring 141. The cover is fixedly connected to the inner wall of the atomizing chamber 1 via a horizontal intake pipe 143. There are four horizontal intake pipes 143 arranged radially around the outer periphery of the cover; one end of the horizontal intake pipe 143 is sealed and fixedly connected to the outer wall of the annular cover 142 (e.g., by welding), and the other end of the horizontal intake pipe 143 is inserted into a through hole in the side wall of the atomizing chamber 1 and sealed and fixedly connected (e.g., by welding).

[0041] Reference Figure 10 The expansion component 14 also includes an air intake structure; the top of the air intake structure is connected to the high-pressure gas belt 14132 and is used to discharge the inert gas in the high-pressure gas belt 14132 (by suction) to increase the taper increment of the droplet portion 312, that is, to increase the outward expansion of the droplet portion 312, thereby reducing the probability and quantity of satellite powder formation.

[0042] Reference Figure 10 The air intake structure includes an intake horizontal pipe 143, a first air pump 146, a U-shaped pipe 147, and a diversion pipe 148. One end of the intake horizontal pipe 143 is connected to the annular cover 142 (within which the high-pressure air belt 14132 is located), and the other end is connected to the first air pump 146 via a first air delivery pipe 1461. The first air pump 146 is used to extract the inert gas from the high-pressure air belt 14132 and discharge it through the U-shaped pipe 147 and the diversion pipe 148 (for depressurization). The housing of the first air pump 146 is fixedly connected to the outer wall of the atomizing chamber 1 (e.g., by heat-resistant bolts). The second air delivery pipe 1462, the U-shaped pipe 147, and the diversion pipe 148 are connected and communicate with each other via a T-junction. The end of the second air delivery pipe 1462 away from the T-junction is connected and communicated with the first air pump 146. The first air delivery pipe 1461 and the second air delivery pipe 1462 are vertically arranged on the outside of the atomizing chamber 1.

[0043] Reference Figure 10 A sorting column 4 is provided in the middle of the atomizing chamber 1, and the sorting column 4 is located below the droplet section 312. The sorting column 4 is cylindrical in shape. A first annular groove 41 is provided between the outer wall of the sorting column 4 and the inner wall of the atomizing chamber 1, and an inverted conical groove 42 is provided inside the sorting column 4. The first annular groove 41 has a top-and-bottom opening structure, and the inverted conical groove 42 has a top-and-bottom opening structure, which is used for the passage of metal powder.

[0044] Reference Figure 10 Because the attraction of the expansion component 14 to the outer edge of the droplet portion 312 is greater than its attraction to the interior, the content of satellite powder at the bottom outer edge of the mixing jet 31 is lower than that at the bottom middle of the mixing jet 31. The inverted conical groove 42 is used to guide the metal powder falling through the bottom middle of the mixing jet 31 (with a higher content of satellite powder, requiring a crushing process); the first annular groove 41 is used to guide the metal powder falling through the bottom outer edge of the mixing jet 31 (with an even lower content of satellite powder, even close to zero, requiring no special crushing process).

[0045] Reference Figure 10 The suction structure can guide some of the inert gas inside to the bottom opening of the inverted conical groove 42 to form a sorting airflow, which is arranged laterally. The sorting airflow is used to sort satellite powder in the metal powder discharged through the inverted conical groove 42. During the process of the metal powder falling from top to bottom, the smaller single powder particles move a greater distance laterally and will not fall into the lower impact module 5 (the guide vertical hole 511), while the larger satellite powder particles move a smaller distance laterally and will fall into the lower impact module 5 (the guide vertical hole 511).

[0046] Reference Figure 10The top of the outer wall of the sorting column 4 is provided with a first guide cone surface 43, which is used to guide the falling single particles of powder and guide them into the first chute.

[0047] Reference Figure 10 The vertical cross-section of the inverted conical groove 42 is V-shaped.

[0048] During prolonged use, metal powder accumulates on the inclined surface of the sorting column 4 (including the surface of the inverted conical groove 42 and the first guide cone surface 43) and becomes difficult to slide downwards (e.g., due to electrostatic adsorption, or the metal powder impacting the inclined surface, causing it to become uneven). Over time, this leads to a decrease in product yield and an increase in impurity rate when switching the type of metal powder being manufactured; for example, when switching from copper-gold powder to pearlescent powder, the copper-gold powder remaining on the sorting column 4 will mix into the pearlescent powder as an impurity. To solve this problem, refer to... Figure 10 The intake structure delivers the sorting airflow through a U-shaped tube 147. The upper part of the U-shaped tube 147 is inserted into the sorting column 4 to transmit vibrational energy to the sorting column 4. When the inert gas flow passes through the bend of the U-shaped tube 147, it impacts the inner wall of the U-shaped tube 147, causing the U-shaped tube 147 to vibrate. This vibrational energy is transmitted to the sorting column 4, causing the sorting column 4 to vibrate, thereby shaking off the metal powder remaining on its surface and avoiding unnecessary accumulation. In this scheme, the power source of the sorting column 4 is the airflow in the suction structure. Firstly, this simplifies the product structure (without requiring an additional vibration motor), improves reliability, and reduces costs. Secondly, it consumes part of the kinetic energy of the airflow in the suction structure, avoiding the problem that the airflow velocity in the lower part of the atomizing chamber 1 is too high, causing metal powder to fly around instead of accumulating in the storage chamber 101. It also avoids the problem that the inert gas in the lower part of the atomizing chamber 1 flows backward (i.e., upward) along the first annular groove 41 and impacts the metal powder / metal droplets in the droplet section 312 (if there is a backward impact, the probability of metal powder / metal droplets colliding with each other will increase, and the probability and quantity of satellite powder production will increase). Thirdly, it reduces the flow rate of the sorting airflow, avoiding the problem that the satellite powder cannot fall into the impact module 5 due to the excessively high flow rate of the sorting airflow.

[0049] Reference Figure 10 and Figure 11 The sorting column 4 is connected to the inner wall of the atomizing chamber 1 by a first spring 44. Several first springs 44 are arranged radially and in a circumferential array on the outer wall of the sorting column 4. One end of each first spring 44 is fixedly connected to the outer wall of the sorting column 4 (e.g., by bolts), and the other end is fixedly connected to the inner wall of the atomizing chamber 1 (e.g., by bolts). When the sorting column 4 vibrates, the first springs 44 provide it with room to move. The length of the first springs 44 is radially arranged along the sorting column 4.

[0050] Reference Figure 10 The bottom surface of the sorting column 4 is provided with an insertion groove; the upper part of the Z-shaped tube 147 is adapted to be inserted into the insertion groove and fixedly connected to the sorting column 4 (for example, by bolt or by welding).

[0051] Reference Figure 10 A first air valve 1471 is installed at the end of the Z-shaped tube 147 (away from the inverted conical groove 42). The first air valve 1471 (e.g., a ball valve) is located outside the atomizing chamber 1. The user can control the flow rate of the inert gas inside the Z-shaped tube 147 through the first air valve 1471 to adapt it to the sorting operation of the satellite powder. The user can evaluate and obtain the optimal flow rate of the sorting airflow through a limited number of experiments. Because the guide vertical hole 511 has a certain compatibility with the position of the falling satellite powder, and the first spring 44 has different elastic forces when the diameter is different, the user can determine the optimal diameter of the first spring 44 through a limited number of attempts (assuming the material of the first spring 44 remains unchanged; the accuracy of the optimal diameter is 0.1 mm). This optimal diameter is adapted to the flow rate of the sorting airflow, the aperture of the guide vertical hole 511, the (horizontal) axial distance between the guide vertical hole 511 and the bottom opening of the inverted conical groove 42, and the height difference between the bottom of the inverted conical groove 42 and the top of the guide vertical hole 511, so that the satellite powder can fall into the guide vertical hole 511 (precisely) under the premise of receiving vibration energy.

[0052] The Z-shaped tube 147 is inserted into the through hole on the side wall of the atomizing chamber 1 and is sealed at the insertion position (e.g., by a sealing ring).

[0053] Reference Figure 10 and Figure 12 An impact module 5 is located at the lower part of the atomizing chamber 1, below the sorting column 4. The impact module 5 is used to crush the satellite powder obtained by the sorting airflow. The impact module 5 includes a support block 51 and a hollow impact roller 52; the support block 51 has a guide vertical hole 511, and the impact roller 52 is vertically arranged and eccentrically installed in the guide vertical hole 511, which can squeeze the satellite powder. After being squeezed by the impact roller 52 and the support block 51, the sticky parts of the satellite powder break and detach, resulting in single powder particles, thereby increasing the yield of single powder particles and reducing the defect rate.

[0054] Reference Figure 10The suction structure can guide some of the inert gas inside to the impact module 5 to drive the impact roller 52 to rotate. In this scheme, the impact module 5 can consume part of the kinetic energy of the airflow in the suction structure, avoiding the problem that the airflow velocity in the lower part of the atomizing chamber 1 is too high, causing the metal powder to fly around instead of accumulating in the storage chamber 101, and avoiding the problem that the inert gas in the lower part of the atomizing chamber 1 flows backward (i.e., upward) along the first annular groove 41 / second sliding groove and impacts the metal powder / metal droplets in the droplet section 312 (if it impacts backward, the probability of metal powder / metal droplets colliding with each other will increase, and the probability and quantity of satellite powder production will increase, resulting in a higher defect rate).

[0055] Reference Figure 10 The atomizing chamber 1 has an inverted conical storage cavity 101 at its bottom, and a discharge pipe is connected to the bottom of the storage cavity 101. A discharge valve 102 is provided at the bottom of the discharge pipe. A second annular groove 513 is provided between the outer wall of the support block 51 and the inner wall of the atomizing chamber 1. Metal powder (specifically single-particle powder) falling down through the first chute and the sorted single-particle powder can pass through the second annular groove 513 and fall and accumulate in the storage cavity 101. The user can open and close the discharge valve 102 to control whether the storage cavity 101 discharges the single-particle powder inside.

[0056] Reference Figure 10 , Figure 13 and Figure 14 A kinetic energy converter 53 is provided at the top of the guide vertical hole 511. The kinetic energy converter 53 includes a fixed cylinder 531 coaxially arranged with the impact roller 52. The end of the diversion air pipe 148 (away from the tee) is connected and communicates with the top opening of the fixed cylinder 531 (e.g., fixedly connected by welding seal). The fixed cylinder 531 is fixed relative to the support block 51, so that it cannot rotate (to avoid detachment from the diversion air pipe 148). The inert gas discharged through the suction structure can flow through the fixed cylinder 531 and the impact roller 52, driving the impact roller 52 to rotate. The impact roller 52 includes a main shaft 521 and a rotating cylinder 523 sleeved on the outer periphery of the main shaft 521. The top end of the rotating cylinder 523 is provided with a guide cone plate 5231, and the top end of the guide cone plate 5231 is provided with an upper extension ring (e.g., fixedly connected by welding seal). The upper extension ring is inserted into the bottom of the inner cavity of the fixed cylinder 531, and the outer side wall of the upper extension ring is in contact with the inner side wall of the fixed cylinder 531 to prevent metal powder from entering the inner cavity of the impact roller 52. The main shaft 521 and the rotating cylinder 523 are eccentrically arranged; the main shaft 521 and the fixed cylinder 531 are coaxially arranged; the bottom edge of the guide cone plate 5231 is sealed and fixedly connected to the top of the rotating cylinder 523 (e.g., by welding). The main shaft 521, the rotating cylinder 523 and the guide cone plate 5231 rotate synchronously (simultaneously, at the same speed and in the same direction).

[0057] Reference Figure 13 and Figure 14The fixed cylinder 531 contains a second impeller 532 connected to the impact roller 52. The second impeller 532 is fixedly installed on the outer periphery of the top of the main shaft 521 (e.g., by bolts). The top of the main shaft 521 is inserted into the inner cavity of the fixed cylinder 531. When the airflow flows from top to bottom in the inner cavity of the fixed cylinder 531, part of its kinetic energy is absorbed by the second impeller 532 and transferred to the impact roller 52, thereby causing the impact roller 52 to rotate / have a tendency to rotate. The main shaft 521 and the rotating cylinder 523 are fixedly connected by a number of first inner support rods 522. The first inner support rods 522 are arranged in a circumferential array along the main shaft 521. One end of the first inner support rod 522 is fixedly connected to the main shaft 521 (e.g., by bolts), and the other end is fixedly connected to the inner wall of the rotating cylinder 523 (e.g., by bolts).

[0058] Reference Figure 15 The impact roller 52 is equipped with helical fins 524. The inner edge of the helical fins 524 is sealed and fixedly connected to the main shaft 521 (e.g., by welding), and the outer edge is fixedly and sealedly connected to the inner wall of the rotating cylinder 523 (e.g., by welding). The axis of rotation of the helical fins 524 is parallel to the axis of the main shaft 521. When the airflow flows from top to bottom in the inner cavity of the rotating cylinder 523, part of its kinetic energy is absorbed by the helical fins 524 and transferred to the impact roller 52, thereby causing the impact roller 52 to rotate / have a tendency to rotate.

[0059] The second impeller 532 and the spiral fins 524 are used to absorb the kinetic energy of the airflow.

[0060] Reference Figure 13 and Figure 14 The support block 51 is fixedly connected to the atomizing chamber 1 by a number of external support rods 55. The external support rods 55 are disposed within the second annular groove 513 and arranged radially along the atomizing chamber 1, forming a circumferential array around the support block 51. One end of each external support rod 55 is fixedly connected to the support block 51 (e.g., by bolts), and the other end is fixedly connected to the atomizing chamber 1 (e.g., by bolts). Metal powder can pass through the gaps between adjacent external support rods 55 and fall downwards, thus avoiding obstruction of the material flow.

[0061] Reference Figure 13 and Figure 14 The fixed cylinder 531 and the support block 51 are fixedly connected by a plurality of first fixed rods 5311. A material drop ring groove is provided between the outer wall of the fixed cylinder 531 and the inner wall of the guide vertical hole 511; the first fixed rods 5311 are disposed in the material drop ring groove and arranged radially along the guide vertical hole 511. One end of the first fixed rod 5311 is fixedly connected to the fixed cylinder 531 (e.g., by bolts) and the other end is fixedly connected to the support block 51 (e.g., by bolts). Metal powder can pass through the gap between adjacent first fixed rods 5311 and fall downward, thereby avoiding obstruction of the material flow.

[0062] Reference Figure 14 The main shaft 521 and the fixed cylinder 531 are rotatably connected via a first cross 5312. From a top view, the first cross 5312 is cross-shaped; a first insertion hole is provided in the center of the first cross 5312, into which the main shaft 521 (top) is inserted and connected via a bearing. A support ring 5211 is fixedly installed on the outer wall of the main shaft 521 (e.g., via an integral fixed connection), and the support ring 5211 presses against the top surface of the first cross 5312, thereby preventing the main shaft 521 from sagging. Airflow can pass through the fan-shaped gap of the first cross 5312, allowing for smooth flow.

[0063] Reference Figure 14 A base support plate 542 is fixedly mounted on the lower surface of the second cross 543 (e.g., by bolts); a second motor 54 is mounted below the base support plate 542, and the second output shaft 541 of the second motor 54 is inserted into the through hole of the base support plate 542 and can rotate; the second output shaft 541 is rotatably connected to the support block 51 via the second cross 543. From a top view, the second cross 543 is cross-shaped; a second insertion hole is provided in the middle of the second cross 543, and the second output shaft 541 is inserted into the second insertion hole and connected by a bearing. Airflow can pass through the fan-shaped gap of the second cross 543, thus allowing for smooth flow. The top end of the second output shaft 541 is coaxially and fixedly connected to the bottom end of the main shaft 521 (e.g., by bolts). The second motor 54 is electrically connected to an external power supply or battery. When the airflow velocity discharged from the suction structure is insufficient to drive the impact roller 52 to rotate, the second motor 54 acts as a motor and, together with the second impeller 532 / spiral fin 524, applies torque to the impact roller 52 to drive it to rotate. When the airflow velocity discharged from the suction structure is sufficient to drive the impact roller 52 to rotate, the second motor 54 acts as a generator, converting part of the kinetic energy of the impact roller 52 into electrical energy for discharge, thereby increasing the rotational resistance of the impact roller 52 and thus absorbing the kinetic energy of the airflow more quickly and significantly.

[0064] Reference Figure 10 The support block 51 has an upwardly protruding cavity with an opening at the bottom. The upwardly protruding cavity is connected to the heat exchanger 6 (e.g., a plate heat exchanger for cooling inert gas) through a return horizontal pipe 61. The heat exchanger 6 is connected to the second air pump 7 through a first return pipe 71. The second air pump 7 is connected to the jet channel 12 through a second return pipe 72. Both the heat exchanger 6 and the second air pump 7 are located outside the atomizing chamber 1.

[0065] Reference Figure 10The suction end of the return horizontal pipe 61 (i.e. the end away from the heat exchanger 6) is located at the top of the upper convex cavity. When it draws inert gas, it can only form an upward airflow in the upper convex cavity (this upward airflow will not impact the droplet part 312 in the reverse direction), and will not form an upward airflow in the second annular groove 513.

[0066] The intake horizontal pipe 143 is a hard alloy pipe (such as platinum-rhodium alloy), which serves two purposes: to transport air and to support the annular cover 142.

[0067] Reference Figure 10 The inverted conical groove 42 is eccentrically set; the position of the guide vertical hole 511 (relative to each other on the cross-section of the atomizing chamber 1) is adapted to the position of the bottom opening of the inverted conical groove 42 (relative to each other on the cross-section of the atomizing chamber 1), so that the guide vertical hole 511 can receive the falling satellite powder.

[0068] The present invention also includes an electrical cabinet, which is fixedly installed on the floor of the processing workshop by bolts; the first air pump 146, the second air pump 7, the first motor 144, the second motor 54, and the storage battery are respectively connected to the electrical cabinet by wires and signal lines; the electrical cabinet is connected to the external power supply and the external controller (such as a computer or a PLC programmable logic controller) by wires and signal lines, and the external controller controls the start-stop and other working states of the first air pump 146, the second air pump 7, the first motor 144, the second motor 54, and the storage battery through the electrical cabinet.

[0069] Both the first motor 144 and the second motor 54 are controllable motors (such as servo motors or stepper motors). By inputting electrical signals to the controllable motors through an external controller, the speed, number of revolutions per rotation, angle of rotation per rotation, and start / stop timing of the controllable motors can be controlled.

[0070] Inert gases such as nitrogen, carbon dioxide, argon, and helium are used.

[0071] Reference Figure 10 The upper part of the support block 51 is provided with a relief slope on the side away from the Z-shaped tube 147, which is used to guide the sorted single powder particles into the second annular groove 513.

[0072] Reference Figure 12 and Figure 13 The swirl cylinder 523 is a cylindrical structure with openings at the top and bottom; the guide vertical hole 511 is a circular hole structure with openings at the top and bottom.

[0073] Reference Figure 11A damper is installed in the first annular groove 41. One end of the damper is connected to the outer wall of the sorting column 4, and the other end is connected to the inner wall of the atomizing chamber 1. It is used to quickly consume the excess kinetic energy of the sorting column 4, thereby preventing the kinetic energy transmitted to the sorting column 4 by the Z-shaped tube 147 from exceeding the threshold. Multiple dampers are arranged in a circumferential array on the outer periphery of the sorting column 4. There is a leakage gap between adjacent dampers to allow metal powder to fall off and prevent clogging of the first annular groove 41.

[0074] The metal powder production process involves manufacturing metal powder using a metal powder production line, and the steps include: S1. Inert gas impacts the molten metal 3 to obtain a mixed jet 31.

[0075] S2. The expansion ring 141 rotates, forming a low-pressure gas band 14131 in the first gap 3120, driving the droplet part 312 to expand outward; at the same time, the suction structure draws inert gas from the high-pressure gas band 14132.

[0076] S3. Metal powder at the bottom outer edge of the mixed jet 31 falls and penetrates the first annular groove 41; metal powder at the bottom middle of the mixed jet 31 falls and penetrates the first annular groove 41.

[0077] S4. The sorting airflow separates the satellite powder, and then the impact module 5 crushes the satellite powder to obtain metal powder. During the process, the suction structure diverts the internal airflow to the area below the sorting column 4 and inside the impact module 5 to form a sorting airflow and drive the impact roller 52 to rotate.

[0078] The present invention has a simple structure and reliable function. The expansion component 14 is used to increase the taper of the droplet portion 312 to reduce the number of metal droplets and / or metal powder contained in the unit volume of the droplet portion 312 (i.e., the density is reduced). This reduces the probability of metal droplets contacting each other, the probability of metal droplets contacting each other and metal powders, and the probability of (incompletely cured) metal powders contacting and colliding with each other, thereby reducing the probability and quantity of satellite powder formation and reducing the defect rate.

[0079] When the annular cover 142 covers the expansion ring 141, it can partially block the high-pressure gas band 14132 and keep it under pressure (reducing the exchange of substances with the outer inert gas), thereby allowing the high-pressure gas band 14132 to drop rapidly and significantly, thereby reducing the gas pressure of the low-pressure gas band 14131, thus applying a greater pulling force to the droplet portion 312, resulting in a larger taper of the droplet portion 312 and a lower probability of satellite powder formation.

[0080] To generate a sufficient pressure difference to drive the droplet portion 312 to expand outward, the airflow within the suction structure needs to have a high velocity, meaning the inert gas at that location has significant kinetic energy. To avoid wasting kinetic energy and to prevent the formation of an upward airflow impacting the droplet portion 312 within the first annular groove 41 (thus avoiding the problem of increased satellite powder generation due to upward impact on the droplet portion 312), rapid energy dissipation is achieved through a sorting airflow, vibration transmission, and a crushing module. The energy transfer manifests as increased metal powder velocity, vibration of the sorting column 4, rotation of the impact roller 52, and satellite powder breakage. Furthermore, since the energy storage components (i.e., metal powder, sorting column 4, impact roller 52, satellite powder, etc.) do not adversely affect the droplet portion 312, the optimized defect rate is not negated.

[0081] The sorting column 4 and the impact module 5 can block the inert gas discharged through the intake structure to prevent the formation of an upward airflow in the cavity of the atomizing chamber 1 for impacting the mixing jet 31.

[0082] Inert gases are used to form metal droplets and to increase the cooling rate of metal powder (compared to vacuum powdering technology), thereby reducing the probability of adhesion and the probability and number of satellite powder formation.

[0083] In the description of this invention, it should be noted that the terms "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0084] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or a connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0085] In conclusion, for those skilled in the art, any changes, modifications, substitutions, or variations made to this invention based on the guidance of this invention, without departing from the principles and spirit of this invention, still fall within the protection scope of this invention.

Claims

1. A metal powder production line, characterized in that: The equipment includes a powder manufacturing device; the powder manufacturing device includes an atomizing chamber (1), the top of the inner cavity of the atomizing chamber (1) is provided with a material injection channel (11) and a jet channel (12); the inert gas ejected through the jet channel (12) can impact the molten metal (3) discharged through the material injection channel (11) to form a mixed jet (31), the mixed jet (31) includes a liquid film part (311) and a droplet part (312). An expansion component (14) is circumferentially sleeved on the outer side of the junction between the liquid film portion (311) and the droplet portion (312). The expansion component (14) is used to increase the taper of the droplet portion (312) to reduce the number of metal droplets and / or metal powder contained in a unit volume of the droplet portion (312).

2. The metal powder production line according to claim 1, characterized in that: The expansion assembly (14) includes an expansion ring (141); the expansion ring (141) includes an upper ring body (1411), a lower ring body (1412) and a first blade (1413); the first blade (1413) is arranged in a circumferential array between the upper ring body (1411) and the lower ring body (1412); a first gap (3120) is provided between the expansion ring (141) and the mixing jet (31); the expansion ring (141) is rotatable to reduce the air pressure in the first gap (3120).

3. The metal powder production line according to claim 2, characterized in that: When the expansion ring (141) rotates, a low-pressure air band (14131) and a high-pressure air band (14132) are formed on the inner and outer sides respectively; the expansion assembly (14) also includes an annular cover (142), which is adapted to cover the outer periphery of the expansion ring (141) and is used to limit the high-pressure air band (14132).

4. The metal powder production line according to claim 3, characterized in that: The expansion component (14) also includes an air intake structure; the top of the air intake structure is connected to the high-pressure gas belt (14132) for discharging inert gas in the high-pressure gas belt (14132) to increase the taper of the droplet portion (312).

5. The metal powder production line according to claim 4, characterized in that: The atomizing chamber (1) is provided with a sorting column (4) in the middle; a first annular groove (41) is provided between the outer wall of the sorting column (4) and the inner wall of the atomizing chamber (1); and an inverted conical groove (42) is provided inside the sorting column (4). The content of satellite powder at the bottom outer edge of the mixed jet (31) is lower than the content of satellite powder at the bottom middle position of the mixed jet (31); the inverted conical groove (42) is used to guide the metal powder falling through the middle position of the mixed jet (31); The air intake structure can guide some of the internal inert gas to the bottom opening of the inverted conical groove (42) to form a sorting airflow; the sorting airflow is used to sort satellite powder in the metal powder discharged through the inverted conical groove (42).

6. The metal powder production line according to claim 5, characterized in that: The air intake structure delivers the sorting airflow through a zigzag tube (147); the upper part of the zigzag tube (147) is inserted into the sorting column (4) to transmit vibration energy to the sorting column (4).

7. The metal powder production line according to claim 6, characterized in that: The atomizing chamber (1) is provided with an impact module (5) at the bottom. The impact module (5) is used to break the satellite powder obtained by the sorting airflow. The impact module (5) includes a support block (51) and a hollow impact roller (52). The support block (51) is provided with a guide vertical hole (511). The impact roller (52) is installed eccentrically in the guide vertical hole (511) and can squeeze the satellite powder. The air intake structure can guide some of the inert gas inside to the impact module (5) to drive the impact roller (52) to rotate.

8. The metal powder production line according to claim 7, characterized in that: The top of the guide vertical hole (511) is provided with a kinetic energy converter (53); the kinetic energy converter (53) includes a fixed cylinder (531) coaxially arranged with the impact roller (52); the inert gas discharged through the suction structure can flow through the fixed cylinder (531) and the impact roller (52) to drive the impact roller (52) to rotate. The fixed cylinder (531) is provided with a second impeller (532) connected to the impact roller (52), and / or the impact roller (52) is provided with a spiral fin (524).

9. The metal powder production line according to claim 8, characterized in that: The support block (51) has an upper convex cavity with a bottom opening. The upper convex cavity is connected to the heat exchanger (6) through a return horizontal pipe (61). The heat exchanger (6) is connected to the second air pump (7) through a first return pipe (71). The second air pump (7) is connected to the jet channel (12) through a second return pipe (72). The sorting column (4) and the impact module (5) can block the inert gas discharged through the air intake structure to prevent the formation of an upward airflow in the cavity of the atomizing chamber (1) for impacting the mixing jet (31).

10. A metal powder production process, characterized in that, The metal powder is manufactured using the metal powder production line of claim 9, comprising the following steps: S1. The inert gas impacts the molten metal (3) to obtain the mixed jet (31). S2. The expansion ring (141) rotates to form the low-pressure gas band (14131) in the first gap (3120), driving the droplet part (312) to expand outward; at the same time, the suction structure draws inert gas from the high-pressure gas band (14132). S3, the metal powder at the bottom outer edge of the mixed jet (31) falls and penetrates the first annular groove (41); the metal powder at the bottom middle of the mixed jet (31) falls and penetrates the first annular groove (41). S4. The sorting airflow sorts out the satellite powder, and then the impact module (5) crushes the satellite powder to obtain metal powder. During the process, the air intake structure diverts the internal airflow to the area below the sorting column (4) and inside the impact module (5) to form the sorting airflow and drive the impact roller (52) to rotate.

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