A grading screening and cooling system for aluminum powder production

Abstract

The utility model discloses a kind of aluminium powder production with grading screening cooling system, including cooling device and grading device, cooling device first cooler and second cooler, the top of first cooler is provided with aluminium powder import, upper portion is provided with nitrogen import, nitrogen import end is connected with nitrogen conveying pipe, nitrogen conveying pipe is provided with nitrogen pre-cooler, the inside of first cooler is provided with multiple cooling layer boards, first discharge port is provided at the bottom of the connecting place of first cooler and second cooler, screen is obliquely arranged in second cooler, the top of second cooler is provided with first gas outlet, grading device includes multiple series connection's airflow classifier, airflow classifier in first end is communicated with first gas outlet, airflow classifier in terminal end is connected with pulse dust collector, nitrogen discharge pipe is connected on the exhaust port of pulse dust collector. The device not only can improve the cooling effect of atomized aluminium powder, but also can improve the grading efficiency of airflow classifier.

Description

Technical Field

[0001] This utility model belongs to the field of metal powder preparation and production technology, specifically relating to a grading and screening cooling system for aluminum powder production. Background Technology

[0002] Nitrogen-atomized aluminum powder is a spherical aluminum powder produced from aluminum ingots using nitrogen atomization. It features low oxygen content, good flowability, and an active aluminum content of no less than 98.0%. The production process takes place in a nitrogen-protected system. Nitrogen atomization technology melts the aluminum ingots and forms spherical particles, which are then graded and packaged to obtain the final product. Grading and screening are essential steps in the production of nitrogen-atomized aluminum powder, primarily aimed at improving the purity and uniformity of the atomized powder. Currently, the grading and screening equipment for nitrogen-atomized aluminum powder mainly includes a heat exchanger, a cooling tank, a grading device, and a pulse dust collector. In operation, the nitrogen is first cooled by the heat exchanger, and then the cooled nitrogen is used to pneumatically convey the aluminum powder. The nitrogen-carrying aluminum powder first enters the cooling tank for grading, collecting the largest aluminum powder particles. Then, the nitrogen-carrying aluminum powder enters multiple classifiers connected in series for further grading. After grading, the nitrogen undergoes a final purification process by a cyclone dust collector before being discharged. The existing aluminum powder grading device has the following shortcomings during use: First, the heat exchanger has a simple structure, and the cooling effect is not good when using nitrogen gas for cooling. After the nitrogen gas cools the aluminum powder in the aluminum powder tank, it takes a long time to cool the powder effectively, which seriously affects the grading efficiency of the subsequent nitrogen atomization of the aluminum powder. Second, the existing cooling tank structure is not reasonably designed; the nitrogen gas cannot mix well with the aluminum powder during cooling, resulting in uneven cooling and an unsatisfactory cooling effect. Therefore, it is objectively necessary to develop a grading and screening cooling system for aluminum powder production with a reasonable structural design that can improve both the cooling effect and production efficiency. Summary of the Invention

[0003] The purpose of this invention is to provide a graded screening and cooling system for aluminum powder production that has a reasonable structural design, which can improve both the cooling effect and production efficiency of aluminum powder.

[0004] The purpose of this utility model is achieved as follows: It includes a cooling device and a grading device. The cooling device includes two inclined and oppositely arranged first and second coolers, with their upper ends far apart and their bottoms connected. The first cooler has an aluminum powder inlet at its top and a nitrogen inlet at its upper part. A nitrogen delivery pipe is connected to the end of the nitrogen inlet, and a nitrogen precooler is installed on the nitrogen delivery pipe. Multiple cooling plates are arranged inclined downwards at equal intervals from top to bottom inside the first cooler. A first discharge port is located at the bottom of the connection between the first and second coolers. A screen is inclinedly arranged inside the second cooler near the first discharge port, and a first air outlet is located at the top of the second cooler. The grading device includes multiple airflow classifiers connected in series. The first airflow classifier is connected to the first air outlet through a first connecting pipe, and the last airflow classifier is connected to a pulse dust collector through a second connecting pipe. A nitrogen discharge pipe is connected to the exhaust port of the pulse dust collector, and an air pump is installed on the nitrogen discharge pipe.

[0005] Compared with existing technologies, the advantages of this device are as follows: First, the structure of the cooling device is optimized. The first and second coolers in the cooling device are set in a V-shape. After the atomized aluminum powder enters the first cooler, the cooled nitrogen gas blows the atomized aluminum powder. During this process, the cooling plates in the first cooler can distribute the nitrogen gas flow in layers, allowing the nitrogen gas to contact the atomized aluminum powder multiple times within the first cooler. This increases the number of times the atomized aluminum powder comes into contact with nitrogen gas, achieving uniform cooling of the atomized aluminum powder. At the same time, the multi-layered plates can slow down the flow rate of the atomized aluminum powder and prolong the contact time with nitrogen gas. In addition, when the atomized aluminum powder and nitrogen gas flow mix and cool in the first cooler before entering the second cooler, the screen can... The device employs two main methods: First, it performs preliminary screening of aluminum powder to separate large particles. The aluminum powder and nitrogen gas flow after sieving are then redirected into the second cooler. This extends the contact time between the atomized aluminum powder and nitrogen, thus prolonging the cooling time and improving the cooling effect. Second, the structure of the nitrogen precooler is optimized. The precooler increases the contact area between nitrogen and the cooling medium, rapidly reducing the nitrogen's cooling temperature. After cooling, the nitrogen enters the first cooler, quickly cooling the aluminum powder and increasing the cooling rate and time. This, in turn, improves the classifying efficiency of the air classifier. This device boasts advantages such as reasonable structure, significant cooling effect, and high production efficiency, making it easy to promote and use. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2This is a schematic diagram of the structure of the nitrogen precooler 5 in this utility model; Figure 3 This is a schematic diagram of the structure of the nitrogen classifier 6 in this utility model; In the diagram: 1-First cooler, 101-Cooling plate, 102-First discharge port, 2-Second cooler, 201-Screen, 202-First air outlet, 3-Aluminum powder inlet, 4-Nitrogen delivery pipe, 5-Nitrogen precooler, 501-Box, 502-Air inlet box, 503-Baffle, 504-Upper distribution box, 505-Lower distribution box, 506-Cooling pipe, 507-Air inlet pipe, 508-Rotating shaft, 509-First motor, 510-Medium inlet, 511-Medium outlet, 512-Air outlet pipe, 6-Nitrogen distributor Stager, 601-Upper cone, 602-Intermediate cylinder, 603-Lower cone, 604-Second discharge port, 605-Air inlet, 606-Grading cylinder, 607-Top cover, 608-Grading wheel, 609-Drive shaft, 610-Second motor, 611-Rotating tube, 612-Exhaust pipe, 613-Lifting mechanism, 614-Lifting arc plate, 615-Brush bristles, 7-First connecting pipe, 8-Second connecting pipe, 9-Bag dust collector, 10-Nitrogen discharge pipe, 11-Air pump, 12-Nitrogen buffer tank, 13-Circulation pipe. Detailed Implementation

[0007] The present invention will be further described below with reference to the accompanying drawings, but this description is not intended to limit the present invention in any way. Any changes or improvements made based on the teachings of the present invention shall fall within the protection scope of the present invention.

[0008] like Figures 1-3As shown, this utility model includes a cooling device and a grading device. The cooling device includes two inclined and oppositely arranged first coolers 1 and second coolers 2. The upper ends of the first coolers 1 and second coolers 2 are far apart, while the bottoms of the first coolers 1 and second coolers 2 are connected to each other. An aluminum powder inlet 3 is provided at the top of the first cooler 1. Atomized aluminum powder, after being atomized by the atomizing device, enters the first cooler through the aluminum powder inlet 3. A nitrogen inlet is provided at the top, and a nitrogen delivery pipe 4 is connected to the end of the nitrogen inlet. The nitrogen delivery pipe 4 is used to deliver nitrogen into the first cooler 1. A nitrogen precooler 5 is provided on the nitrogen delivery pipe 4. Multiple cooling plates 101 are arranged inclined downwards at equal intervals from top to bottom inside the first cooler 1. A first discharge port 102 is provided at the bottom of the connection between the first cooler 1 and the second cooler 2. A screen 201 is inclinedly arranged inside the second cooler 2 near the first discharge port 102. A first air outlet 202 is provided on the top of the second cooler 2. The grading device includes multiple air classifiers 6 connected in series. The number of air classifiers 6 can be determined according to the actual process of use. Generally, a structure of 2 to 4 stages is set. The air classifier 6 at the first end is connected to the first air outlet 202 through the first connecting pipe 7. The air classifier 6 at the end is connected to a pulse dust collector 9 through the second connecting pipe 8. The pulse dust collector 9 is a device used in the prior art. Its purpose is to further collect atomized aluminum powder. A nitrogen discharge pipe 10 is connected to the exhaust port of the pulse dust collector 9. An air pump 11 is provided on the nitrogen discharge pipe 10. The air pump 11 is a structure used in the prior art. A finished product can be purchased directly according to the model used.

[0009] The working process of this device is as follows: When it is necessary to classify the atomized aluminum powder generated by the atomizing device, the air pump 11 is turned on. Under the action of the air pump 11, the nitrogen generated by the nitrogen generator enters the nitrogen delivery pipe 4 and first enters the nitrogen precooler 5. The nitrogen precooler 5 can use nitrogen as a cooling medium to cool down the nitrogen. After the nitrogen temperature is reduced, it enters the first cooler 1 through the nitrogen inlet in the form of airflow under the action of the air pump 11. The cooling plate 101 in the first cooler 1 can cool the nitrogen. The nitrogen gas flow is distributed in layers, allowing the nitrogen to come into multiple contacts with the atomized aluminum powder within the first cooler 1. This increases the number of contact times between the nitrogen and the atomized aluminum powder, achieving uniform cooling. Simultaneously, the multi-layered plates 101 slow down the flow rate of the atomized aluminum powder, prolonging the contact time with nitrogen. Furthermore, the atomized aluminum powder and nitrogen gas flow are mixed and cooled in the first cooler 1 before entering the second cooler 2. The screen 201 provides preliminary screening of the aluminum powder, separating out large particles of atomized aluminum powder. Large atomized aluminum powder particles are discharged through the first outlet 102. After being screened by the screen 201, the aluminum powder and nitrogen gas flow change direction and enter the second cooler 2. This further prolongs the contact time between the atomized aluminum powder and nitrogen, extending the cooling time and improving the cooling effect. The temperature of the atomized aluminum powder is significantly reduced after being cooled by the nitrogen gas flow. The cooled atomized aluminum powder flow is discharged from the first outlet 202 and enters the multi-channel air classifier 6 through the first connecting pipe 7. After multiple classifications and screenings in the air classifier 6, atomized aluminum powder with different particle sizes can be obtained. After separation by the air classifier 6, the nitrogen gas flow then enters the pulse dust collector 9 through the second connecting pipe 8. After dust removal by the pulse dust collector 9, the fine aluminum powder carried in the nitrogen gas flow can be separated again, increasing the amount of aluminum powder collected. The nitrogen gas flow after separation by the pulse dust collector 9 can be directly discharged through the nitrogen discharge pipe 10.

[0010] Furthermore, to avoid the waste of resources caused by the direct discharge of nitrogen after dust removal by the pulse dust collector 9, a nitrogen buffer tank 12 is installed on the nitrogen discharge pipe 10 between the air pump 11 and the pulse dust collector 9. The nitrogen buffer tank 12 is equipped with a circulation pipe 13 connected to the nitrogen delivery pipe 4. Both the circulation pipe 13 and the nitrogen delivery pipe 4 are equipped with control valves. The nitrogen discharged through the nitrogen discharge pipe 10 can enter the nitrogen buffer tank 12 for collection. The nitrogen buffer tank 12 is a structure used in the prior art. According to the usage requirements, it is equipped with corresponding pressure gauges, safety valves and other components. After the nitrogen enters the nitrogen buffer tank 12 for pressure and flow buffering, the control valve on the nitrogen delivery pipe 4 can be closed and the control valve on the circulation pipe 13 can be opened. The nitrogen in the nitrogen buffer tank 12 is sent to the nitrogen delivery pipe 4 through the circulation pipe 13 for recycling. This can avoid the waste of nitrogen.

[0011] To improve the cooling effect of nitrogen, the nitrogen precooler 5 includes a housing 501 and an air inlet box 502 located at the top of the housing 501. A partition 503 is provided in the lower part of the housing 501, dividing the inner cavity of the housing 501 into a cooling chamber and an air outlet chamber. A hollow upper distribution box 504 and a lower distribution box 505 are installed vertically at intervals within the cooling chamber. Multiple cooling pipes 506 are evenly distributed between the upper and lower distribution boxes 504 and 505. An air inlet pipe 507 is installed at the top of the upper distribution box 504. The air inlet pipe 507 is rotatably mounted on the top of the housing 501 and extends into the interior of the air inlet box 502. A rotating shaft 508 is fixedly installed on the top of the 07. The rotating shaft 508 is rotatably installed on the top of the air intake box 502. A first motor 509, rotatably connected to the rotating shaft 508, is installed above the air intake box 502. The first motor 509 is a structure used in the prior art, and a finished product can be directly purchased according to the power required. Multiple small air intake holes are evenly distributed on the air intake pipe located inside the air intake box 502. A medium inlet 510 is provided at the lower part of the cooling chamber, and a medium outlet 511 is provided at the upper part of the cooling chamber. An exhaust pipe 512 is installed at the bottom of the lower distribution box 505. The exhaust pipe 512 is rotatably installed on the partition 503 and communicates with the exhaust chamber. Nitrogen gas is present. One end of the delivery pipe 4 is connected to the inlet chamber 502, and the other end is connected to the outlet chamber. When the nitrogen is cooled by the nitrogen precooler 5, the cooling medium is first delivered into the chamber 502 through the medium inlet 510. The cooling medium can be cold air or cooling water at a low temperature. After the cooling medium enters the chamber 502, the first motor 509 is turned on. The first motor 509 drives the rotating shaft 508 to rotate. The rotation of the rotating shaft 508 can drive the inlet pipe 507, the upper distribution box 504, the cooling pipe 506, the lower distribution box 505, and the outlet pipe 512 to rotate synchronously. When the nitrogen enters the inlet chamber 502 through the nitrogen delivery pipe 4, it enters the inlet pipe through the small inlet hole in sequence. Within the inlet pipe 507, upper distribution box 504, cooling pipe 506, lower distribution box 505, and outlet pipe 512, as the inlet pipe 507, upper distribution box 504, cooling pipe 506, lower distribution box 505, and outlet pipe 512 rotate, nitrogen can come into contact with the cooling medium inside the housing 501. During the contact process, the cooling medium can cool the nitrogen. After being cooled, the nitrogen enters the outlet chamber and then enters the first cooler 1. The cooling medium, after cooling the nitrogen, is discharged from the medium outlet 511. Preferably, in order to increase the contact time between nitrogen and the cooling medium and improve the cooling effect of nitrogen, the cooling pipe 506 is a corrugated pipe structure.

[0012] Furthermore, the air classifier 6 includes an upper cone 601, an intermediate cylinder 602, and a lower cone 603 arranged sequentially from top to bottom. The lower cone 603 has a second discharge port 604 at its top, and the intermediate cylinder 602 has an air inlet 605. A classifying cylinder 606 is detachably mounted on the top of the upper cone 601, and a top cover 607 is detachably mounted on the top of the classifying cylinder 606. A classifying wheel 608 is horizontally arranged inside the classifying cylinder 606. The classifying wheel 608 is a type of existing technology. In this structure, the classifying particle size of the classifying wheels 608 connected in series in multiple airflow classifiers 6 gradually decreases along the airflow direction. A drive shaft 609 is mounted on one end of each classifying wheel 608. The drive shaft 609 is rotatably mounted on the side wall of the classifying cylinder 606 and is connected to a second motor 610. The second motor 610 is a structure used in the prior art, and finished products are directly purchased based on the required power. The second motor 610 is mounted on the outer wall of the classifying cylinder 606 via a bracket. A rotating pipe 611 is mounted on the other end of each classifying wheel 608 and communicates with it. One end of the rotating pipe 611 is rotatably mounted inside an exhaust pipe 612, which penetrates the side wall of the classifying cylinder 606. The working process of a single airflow classifier 6 is as follows: the second motor 610 is turned on, and the second motor 610 drives the classifying wheel 608 and the rotating pipe 611 to rotate via the drive shaft 609. When atomized aluminum powder enters the intermediate cylinder 602 with the nitrogen airflow, the atomized aluminum powder flows upward with the nitrogen airflow. When the nitrogen airflow and atomized aluminum powder flow to the rotating classifying wheel... At wheel 608, the rotating classifying wheel 608 can classify and screen the atomized aluminum powder. After being screened by the classifying wheel 608, the atomized aluminum powder with larger particle size falls along the upper cone 601, the middle cylinder 602 and the lower cone 603 and is discharged through the second outlet 604. The aluminum powder with finer particle size and the nitrogen gas flow enter the interior of the classifying wheel 608, enter the exhaust pipe 612 through the rotating pipe 611, and are then discharged through the exhaust pipe 612. The rotating classifying wheel 608 can be used to classify and screen the atomized aluminum powder.

[0013] Furthermore, to facilitate the maintenance of the grading wheel 608, the grading cylinder 606 and the upper cone cylinder 601, as well as the grading cylinder 606 and the top cover 607, are connected by flange assemblies. The flange assembly is a device used in the prior art, mainly including a flange, a gasket, and fasteners.

[0014] Furthermore, to prevent excessive aluminum powder from clogging the grading wheel 608 and affecting grading efficiency, a lifting mechanism 613 is installed above the top cover 607. A lifting arc plate 614 connected to the lifting mechanism 613 is installed inside the grading cylinder 606. The curvature of the lifting arc plate 614 is adapted to the grading wheel 608. Brush bristles 615 are provided on the bottom surface of the lifting arc plate 614. After the grading wheel 608 has been used for a period of time, the lifting mechanism 613 can drive the lifting arc plate 614 to move downwards. When the lifting arc plate 614 moves downwards until the brush bristles 615 contact the grading wheel 608, the second motor 610 drives the grading wheel 608 to rotate. The brush bristles 615 can then clean the rotating grading wheel 608, preventing excessive atomized aluminum powder from clogging it. After the grading wheel 608 is cleaned, the lifting mechanism 613 drives the lifting arc plate 614 upwards to return to its original position. Preferably, to improve ease of use, the lifting mechanism 613 is a hydraulic cylinder or a pneumatic cylinder.

Claims

1. A grading and screening cooling system for aluminum powder production, comprising a cooling device and a grading device, characterized in that: The cooling device includes two inclined and oppositely arranged first coolers (1) and second coolers (2). The upper ends of the first coolers (1) and second coolers (2) are far apart from each other, and the bottoms of the first coolers (1) and second coolers (2) are connected to each other. An aluminum powder inlet (3) is provided at the top of the first cooler (1), and a nitrogen inlet is provided at the top. A nitrogen delivery pipe (4) is connected to the end of the nitrogen inlet. A nitrogen precooler (5) is provided on the nitrogen delivery pipe (4). Multiple cooling plates (101) are inclined downwards at equal intervals from top to bottom inside the first cooler (1). The connection between the first cooler (1) and the second cooler (2) is as follows: The bottom of the device is provided with a first discharge port (102). A screen (201) is inclinedly arranged in the second cooler (2) near the first discharge port (102). The top of the second cooler (2) is provided with a first air outlet (202). The grading device includes multiple air classifiers (6) connected in series. The air classifier (6) at the first end is connected to the first air outlet (202) through a first connecting pipe (7). The air classifier (6) at the end is connected to a pulse dust collector (9) through a second connecting pipe (8). A nitrogen discharge pipe (10) is connected to the exhaust port of the pulse dust collector (9). An air pump (11) is provided on the nitrogen discharge pipe (10).

2. The grading and screening cooling system for aluminum powder production according to claim 1, characterized in that: A nitrogen buffer tank (12) is provided on the nitrogen discharge pipe (10) between the air pump (11) and the pulse dust collector (9). A circulation pipe (13) connected to the nitrogen delivery pipe (4) is provided on the nitrogen buffer tank (12). Both the circulation pipe (13) and the nitrogen delivery pipe (4) are equipped with control valves.

3. The grading and screening cooling system for aluminum powder production according to claim 1, characterized in that: The nitrogen precooler (5) includes a housing (501) and an air inlet box (502) located at the top of the housing (501). A partition (503) is provided in the lower part of the housing (501), dividing the inner cavity of the housing (501) into a cooling chamber and an air outlet chamber. A hollow upper distribution box (504) and a lower distribution box (505) are installed vertically and vertically within the cooling chamber. Multiple cooling pipes (506) are evenly distributed between the upper distribution box (504) and the lower distribution box (505). An air inlet pipe (507) is installed at the top of the upper distribution box (504). The air inlet pipe (507) is rotatably mounted on the top of the housing (501) and extends into the interior of the air inlet box (502). A rotating shaft (508) is fixedly installed on the top of (507). The rotating shaft (508) is rotatably installed on the top of the air inlet box (502). A first motor (509) rotatably connected to the rotating shaft (508) is installed above the air inlet box (502). Multiple small air inlet holes are evenly distributed on the air inlet pipe located inside the air inlet box (502). A medium inlet (510) is provided at the lower part of the cooling chamber, and a medium outlet (511) is provided at the upper part of the cooling chamber. An air outlet pipe (512) is installed at the bottom of the lower distribution box (505). The air outlet pipe (512) is rotatably installed on the partition (503) and communicates with the air outlet chamber. One end of the nitrogen delivery pipe (4) is connected to the air inlet box (502), and the other end is connected to the air outlet chamber.

4. The grading and screening cooling system for aluminum powder production according to claim 3, characterized in that: The cooling pipe (506) has a corrugated pipe structure.

5. The grading and screening cooling system for aluminum powder production according to claim 1, characterized in that: The air classifier (6) includes an upper cone (601), an intermediate cylinder (602), and a lower cone (603) arranged sequentially from top to bottom. A second discharge port (604) is provided at the top of the lower cone (603). An air inlet (605) is provided on the intermediate cylinder (602). A classifying cylinder (606) is detachably mounted on the top of the upper cone (601). A top cover (607) is detachably mounted on the top of the classifying cylinder (606). A classifying wheel (608) is horizontally arranged inside the classifying cylinder (606). A drive shaft (609) is installed at one end of the grading wheel (608). The drive shaft (609) is rotatably mounted on the side wall of the grading cylinder (606) and is connected to a second motor (610). The second motor (610) is mounted on the outer wall of the grading cylinder (606) by a bracket. A rotating pipe (611) communicating with the other end of the grading wheel (608) is installed. One end of the rotating pipe (611) is rotatably mounted inside an exhaust pipe (612). The exhaust pipe (612) is installed through the side wall of the grading cylinder (606).

6. The grading and screening cooling system for aluminum powder production according to claim 5, characterized in that: The grading cylinder (606) and the upper cone cylinder (601), as well as the grading cylinder (606) and the top cover (607), are connected by flange assemblies.

7. The grading and screening cooling system for aluminum powder production according to claim 5, characterized in that: A lifting mechanism (613) is installed above the top cover (607). A lifting arc plate (614) connected to the lifting mechanism (613) is installed inside the grading cylinder (606). The curvature of the lifting arc plate (614) is adapted to the grading wheel (608). Brush bristles (615) are provided on the bottom surface of the lifting arc plate (614).

8. The grading and screening cooling system for aluminum powder production according to claim 7, characterized in that: The lifting mechanism (613) is a hydraulic cylinder or a pneumatic cylinder.

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