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CN-121972407-A - Powder hollowness grading device and method based on terminal sedimentation speed difference

CN121972407ACN 121972407 ACN121972407 ACN 121972407ACN-121972407-A

Abstract

The invention relates to the field of powder classification, in particular to a powder hollowness classification device and method based on terminal sedimentation speed difference. The device comprises a feeding unit, a dispersion conveying unit, an air flow classifying unit and a collecting unit, wherein the feeding unit is used for supplying powder, the dispersion conveying unit comprises a conveying channel and two fan blade rotating devices, the conveying channel is obliquely arranged from left to right and is used for receiving the powder supplied by the feeding unit and allowing the powder to slide downwards along the conveying channel, the fan blades of the two fan blade rotating devices are parallelly inlaid in the conveying channel in the front-back direction, the air flow classifying unit comprises an air cavity and an air outlet device, the air cavity is obliquely arranged from left to right, the upper end of the air cavity is an air outlet, the lower end of the air cavity is an air inlet, the air outlet is opposite to the outlet of the lower end of the conveying channel, the air outlet device is used for blowing air to the air inlet of the air cavity, and the collecting unit is used for collecting the powder classified by the air flow classifying unit. According to the invention, the accurate grading of the powder hollowness can be realized based on the density difference, and the purity of the target solid powder is improved.

Inventors

  • LIANG JIABIN
  • Qi Xubin
  • WANG SHUAI
  • Dai Wanxiang
  • LIU FA
  • LUO XIAOHONG

Assignees

  • 六盘山实验室

Dates

Publication Date
20260505
Application Date
20260317

Claims (10)

  1. 1. A powder hollowness grading device based on terminal sedimentation speed difference is characterized in that, Comprising the following steps: a feeding unit (1) for supplying powder; the dispersing and conveying unit (2) comprises a conveying channel (21) and two fan blade rotating devices (22), wherein the conveying channel (21) is obliquely arranged from left to right and is used for receiving the powder supplied by the feeding unit (1) and allowing the powder to slide downwards along the powder, and the fan blades of the two fan blade rotating devices (22) are parallelly embedded in the conveying channel (21) in the front-back direction; The air flow classifying unit (3) comprises an air cavity (31), an air outlet device (32) and a plurality of air flow distribution plates (33), wherein the air cavity (31) is obliquely arranged from left to right upwards, the upper end is an air outlet, the lower end is an air inlet, the air outlet is opposite to the lower end outlet of the conveying channel (21), and the air outlet device (32) is used for blowing air to the air inlet of the air cavity (31); And the collecting unit (4) is used for collecting the powder classified by the airflow classifying unit (3).
  2. 2. The powder hollowness classification device based on the terminal sedimentation velocity difference according to claim 1, wherein, The air conditioner further comprises a flow stabilizing unit, the flow stabilizing unit comprises an air flow buffer chamber and an air flow regulating valve, the air outlet device (32) is communicated with the air inlet of the air cavity (31) through the air flow buffer chamber, and the air flow regulating valve is configured at the air inlet of the air cavity (31).
  3. 3. The powder hollowness classification device based on the terminal sedimentation velocity difference according to claim 1, wherein, The feed unit (1) comprises a screw conveyor (11).
  4. 4. The powder hollowness classification device based on the terminal sedimentation velocity difference according to claim 3, wherein, The feeding unit (1) further comprises dosing means (12) for dosing the screw conveyor (11).
  5. 5. The powder hollowness classification device based on the terminal sedimentation velocity difference according to claim 4, wherein, The dosing device (12) comprises a feeding bin located at the side of the screw conveyor (11), and a screw of the screw conveyor (11) stretches into the feeding bin.
  6. 6. The powder hollowness classification device based on the terminal sedimentation velocity difference according to claim 1, wherein, The collecting unit (4) comprises a collecting tank (41), and the collecting tank (41) is provided with at least two collecting cavities (42) which are arranged in sequence from left to right and are respectively used for receiving falling powder.
  7. 7. The powder hollowness classification device based on the terminal sedimentation velocity difference according to claim 6, wherein, The top view of the collecting tank (41) is divergent from left to right.
  8. 8. The powder hollowness classification device based on the terminal sedimentation velocity difference according to claim 6, wherein, The right edge of each collecting cavity (42) is provided with an arc-shaped baffle plate (43), and in any two adjacent arc-shaped baffle plates (43), the arc-shaped baffle plate (43) on the right side is higher than the arc-shaped baffle plate (43) on the left side.
  9. 9. The powder hollowness classification device based on the terminal sedimentation velocity difference according to claim 6, wherein, The collection unit (4) further comprises collection tanks (44) corresponding to the collection chambers (42), each collection tank (44) being in communication with a corresponding collection chamber (42).
  10. 10. A powder hollowness classification method based on the powder hollowness classification device based on the terminal sedimentation velocity difference according to any one of claims 1-9, characterized in that, Comprising the following steps: after screening pretreatment is carried out on the powder to be classified, the powder is supplied to a conveying channel (21) of a dispersion conveying unit (2) through a feeding unit (1); The powder slides downwards along the conveying channel (21) and is scattered by two fan blade rotating devices (22) which rotate back; The air outlet device (32) blows air into the air cavity (31), is guided by the air cavity (31), and blows air obliquely upwards to the powder scattered and sliding down to the lower end of the conveying channel (21), so as to realize grading of the hollowness of the powder; the collecting unit (4) collects the powder with graded hollowness.

Description

Powder hollowness grading device and method based on terminal sedimentation speed difference Technical Field The invention relates to the field of powder classification, in particular to a powder hollowness classification device and method based on terminal sedimentation speed difference. Background In the fields of powder material preparation and downstream application, high-performance metal powder such as nickel-based alloy powder, stainless steel powder, titanium alloy powder and the like, and partial ceramic and food powder are often produced by adopting technologies such as water vapor atomization, plasma atomization, centrifugal atomization and the like. In these processes, a proportion of hollow powder is inevitably mixed inside the finished powder due to factors such as melt fracture, gas entrainment, solidification shrinkage, etc. The internal closed or semi-closed pore structure of the hollow powder particles leads to the apparent density of the hollow powder particles being significantly lower than that of solid powder with the same components and similar particle sizes. The existence of the hollow powder forms a serious challenge for powder performance and subsequent application, for example, in the application of powder spray welding, forming processing and the like, the existence of the hollow powder can lead to the reduction of powder flowability and uneven forming density, thereby influencing the mechanical property, density and surface quality of a final product, and in the food processing field, the mixing of the hollow powder and the solid powder can lead to inconsistent cooking and curing time and influence the quality stability of the product. The most traditional and widely used method for powder classification for density differences is gravity sedimentation. The basic principle is that in a horizontal airflow field, powder with lower density (hollow powder) is subjected to higher ratio of drag force to gravity, so that the powder is blown to a longer distance or different collecting areas, and separation from high-density powder (solid powder) is realized. However, this method relies mainly on horizontal air flow blowing, and the separation accuracy is difficult to secure. And the factors such as particle agglomeration further aggravate separation precision and separation difficulty. Therefore, there is a need to solve the problems of insufficient precision and high difficulty in the existing separation (fractionation) method. Disclosure of Invention The invention aims to overcome the defects of the prior art, and provides a powder hollowness grading device based on the difference of terminal sedimentation speeds, which can realize accurate grading of powder hollowness based on the difference of densities and improve the purity of target solid powder. In order to solve the technical problems, the technical scheme of the invention is that the powder hollowness classification device based on the difference of terminal sedimentation speeds comprises: a feeding unit for supplying powder; The dispersing and conveying unit comprises a conveying channel and two fan blade rotating devices, wherein the conveying channel is obliquely arranged from left to right and is used for receiving the powder supplied by the feeding unit and enabling the powder to slide downwards along the powder, and the fan blades of the two fan blade rotating devices are parallelly inlaid in the conveying channel in the front-rear direction; The air flow classifying unit comprises an air cavity and an air outlet device, wherein the air cavity is obliquely arranged from left to right, the upper end of the air cavity is an air outlet, the lower end of the air cavity is an air inlet, the air outlet is opposite to the lower end outlet of the conveying channel, and the air outlet device is used for blowing air to the air inlet of the air cavity; and the collecting unit is used for collecting the powder classified by the airflow classifying unit. Further, the air classification unit further comprises a plurality of air distribution plates, and the air distribution plates are arranged in the air cavity at intervals along the front-back direction. Further, the powder hollowness grading device based on the terminal sedimentation speed difference further comprises a steady flow unit, wherein the steady flow unit comprises an airflow buffer chamber and an airflow regulating valve, the air outlet device is communicated with an air inlet of the air cavity through the airflow buffer chamber, and the airflow regulating valve is configured at the air inlet of the air cavity. Further, the feeding unit includes a screw conveyor. Further, the feeding unit further comprises a dosing device for dosing the screw conveyor. Further, the dosing device comprises a feeding bin located at the side of the screw conveyor, and a screw of the screw conveyor extends into the feeding bin. Further, the collecting unit comprises a collecting tank, and t