Ball-milling grading system for flaky zinc powder production

Abstract

The invention discloses a ball milling grading system for flaky zinc powder production. Comprising a negative-pressure feeding roots vacuum pump, a feeding air outlet pipeline, a feeding air outlet valve, a negative-pressure feeding bag-type dust collector, a ball mill, a discharging pipeline, a vacuum valve, an airflow classification assembly, a discharging air return pipeline, a discharging roots vacuum pump, a feeding discharging valve, a discharging valve, a pressure relief emptying valve, a nitrogen supplementing valve and an air return valve. One end of the discharging pipeline is connected with the ball mill, the other end of the discharging pipeline is connected with the airflow classification assembly, the vacuum valve and the discharging valve are arranged on the discharging pipeline, one end of the discharging air return pipeline is connected with the airflow classification assembly, and the other end of the discharging air return pipeline is connected with the airflow classification assembly. The other end is connected with the ball mill. Compared with the prior art, the whole production process is continuous and stable, the safety of the production process is guaranteed, and the product quality is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of zinc powder production, in particular to a ball milling and grading system for producing flaky zinc powder. Background Art

[0002] Heavy-duty anti-corrosion coatings are a type of anti-corrosion coating that can be used in relatively harsh corrosive environments and has a longer protection period than conventional anti-corrosion coatings. Currently, most zinc-rich anti-corrosion coatings that are widely used in the field of heavy-duty anti-corrosion use spherical zinc powder as their main component. However, due to the large gaps between particles when spherical particles are stacked, a larger coating thickness is usually required to ensure a good anti-corrosion effect.

[0003] Due to the uniqueness of its flaky structure, flaky zinc powder forms plane overlaps between surfaces within the coating, greatly reducing the porosity of the coating and effectively blocking the penetration of corrosive media and water. At the same time, the coating formed by the flaky structure has better ductility than the commonly used spherical zinc powder heavy-duty anti-corrosion coating during coating construction. Therefore, the amount of filler required is only one-third of the amount of spherical zinc powder, and it has more excellent anti-corrosion performance and is widely used in coating technologies such as Dacro and Diaomeite.

[0004] At present, the production of flaky zinc powder is basically carried out by ball milling, which is mainly divided into two process routes: wet ball milling process and dry ball milling process. In the wet ball milling process, spherical zinc powder raw materials, grinding balls, grinding solvents, grinding aids, etc. are added to the ball mill for grinding. After the spherical zinc powder is ground into a flake structure, it is filtered, dried, dispersed, and graded to form a finished product. The product produced by this process has stable quality and high metallic zinc content, but the production process of this process is long and the production cost is high. In the dry ball milling process, spherical zinc powder raw materials, grinding balls, grinding aids, etc. are added to the ball mill for grinding. After the spherical zinc powder is ground into a flake structure, it is directly graded to obtain the finished product. This process has obvious processing cost advantages, but because there is no grinding solvent protection in the grinding process, its surface activity is relatively high. When the ball mill system discharges the material for ball material separation and is transported to the grading system, it is prone to severe oxidation when it comes into contact with air, causing heat and even spontaneous combustion, and the safety risk is relatively high.

[0005] In view of this, a ball milling and classifying system for producing flaky zinc powder is proposed. Summary of the invention

[0006] The purpose of the present invention is to provide a ball milling and grading system for the production of flaky zinc powder, which can make the entire production process continuous and stable, ensure the safety of the production process, and greatly improve the product quality.

[0007] The above technical objectives of the present invention are achieved through the following technical solutions:

[0008] A ball mill classification system for producing flaky zinc powder comprises a negative pressure feeding Roots vacuum pump, a feeding air outlet pipe, a feeding air outlet valve, a negative pressure feeding bag dust collector, a ball mill, a discharge pipe, a vacuum valve, an airflow classification component, a discharge return air pipe, a discharge Roots vacuum pump, a feeding unloading valve, a discharge valve, a pressure relief and emptying valve, a nitrogen replenishing valve and a return air valve, wherein one end of the feeding air outlet pipe is connected to the negative pressure feeding Roots vacuum pump, and the other end is connected to the negative pressure feeding bag dust collector, the feeding air outlet valve is arranged on the feeding air outlet pipe, and the A feeding port is provided on the side of the negative pressure loading bag dust collector, and the bottom is connected to the ball mill. The loading and unloading valve is arranged at the bottom of the negative pressure loading bag dust collector, one end of the discharge pipe is connected to the ball mill, and the other end is connected to the airflow classification component. The vacuum valve and the discharge valve are arranged on the discharge pipe, one end of the discharge return air pipe is connected to the airflow classification component, and the other end is connected to the ball mill. The discharge Roots vacuum pump, pressure relief and emptying valve, return air valve and nitrogen replenishment valve are arranged on the discharge return air pipe in sequence.

[0009] In a preferred embodiment, the airflow classification component includes a primary classification main unit, a secondary classification main unit and a discharge bag dust collector, the primary classification main unit and the secondary classification main unit are provided with impeller motors and classification impellers, a primary finished product discharge valve is provided under the primary classification main unit, a secondary finished product discharge valve is provided under the secondary classification main unit, a third finished product discharge valve is provided under the discharge bag dust collector, the discharge return air duct is connected to the discharge bag dust collector, and the discharge duct is connected to the primary classification main unit.

[0010] In a preferred embodiment, a first pressure sensor is provided between the secondary grading main machine and the discharge bag filter.

[0011] In a preferred embodiment, a second pressure sensor is provided on the discharge return air duct, and the second pressure sensor is provided between the discharge bag filter and the discharge Roots vacuum pump.

[0012] In a preferred embodiment, a first cooling water flow regulating valve and an infrared temperature sensor are provided at one end of the ball mill.

[0013] In a preferred embodiment, a pipeline cooling heat exchanger is provided on the discharge return air pipeline, and a second cooling water flow regulating valve is provided on the pipeline cooling heat exchanger.

[0014] In a preferred embodiment, a temperature sensor and an oxygen concentration sensor are provided on the discharge return air duct.

[0015] In a preferred embodiment, a feed pipe is provided at one end of the ball mill, and the discharge return air duct is connected to the feed pipe. The feed pipe includes a pipe body, a sleeve, a driving electromagnet, a movable ring and a plurality of movable rods. A sleeve section is provided on the pipe body, and the driving electromagnet is provided at the end of the sleeve section. The movable ring is sleeved on the sleeve section. The movable ring is made of a magnet. One end of the movable rod is connected to the movable ring. A plurality of movable rods are evenly distributed around the circumference of the sleeve section. A prestressed bending portion is provided on the movable rod so that the movable rod bends without the action of external force. The sleeve is sleeved on the sleeve section, and a movable cavity is provided between the sleeve and the sleeve section for the movable ring to move. A plurality of through holes are provided on the sleeve for the plurality of movable rods to pass through.

[0016] In a preferred embodiment, a pressure strain gauge is provided in the through hole.

[0017] In a preferred embodiment, the driving electromagnets are provided in an even number, and the even number of driving electromagnets uniformly surround the sleeve section.

[0018] Compared with the prior art, the ball milling and grading system for the production of flaky zinc powder of the present invention is firstly the loading link when it is working. The negative pressure loading Roots vacuum pump works so that the spherical zinc powder raw material and grinding aid are sucked in and transmitted through the loading air outlet pipe. In this process, the loading air outlet valve can control the direction of the air flow. After the material reaches the negative pressure loading bag dust collector, the gas-solid separation is carried out through the bag. The raw material and the aid enter the negative pressure loading bag dust collector through the feed port and enter the ball mill under the action of gravity. The loading and unloading valve controls the material flow entering the ball mill.

[0019] After the feeding is completed, the ball mill feed port is closed, and then the vacuum valve is opened to use the vacuum system to extract the air in the system, and then the nitrogen replenishment valve is opened to fill in nitrogen, and this process is repeated several times until the pressure and oxygen concentration in the system reach the predetermined target value. Then the ball mill is started, and grinding balls of a specific size and ratio are placed in the ball mill in advance, and the material grinding operation begins.

[0020] When the grinding is finished, open the nitrogen replenishment valve, inject nitrogen with a purity of 90%-99.9%, and adjust the ball mill speed to a low speed to passivate the surface of the flaky zinc powder in an atmosphere with a trace oxygen concentration. The passivation treatment is intended to improve the performance of the flaky zinc powder, making it more stable during subsequent storage and use, and less prone to adverse chemical reactions such as oxidation. After passivation treatment, the antioxidant capacity of the flaky zinc powder is significantly enhanced.

[0021] After the passivation is completed, open the discharge valve, return air valve and vacuum valve, use the vacuum system to extract the gas again, and then fill the nitrogen replenishment valve with high-purity nitrogen, and alternate several times until the pressure and oxygen concentration in the system meet the requirements. Then start the airflow classification component and the discharge Roots vacuum pump. At this time, the flaky zinc powder in the ball mill is carried out by the airflow and enters the airflow classification component. In the airflow classification component, the flaky zinc powder is classified into finished products of different grades according to the particle size. The finished products of each grade are discharged to the automatic vacuum packaging machine by alternating up and down unloading (locking air unloading) to complete the finished product packaging. After the dust-containing airflow passes through the bag gas-solid separation, the clean gas returns to the ball mill through the discharge return air duct and the discharge Roots vacuum pump, forming a cycle until all the materials in the ball mill are discharged. Thanks to the precise classification function of the airflow classification component, the purity of the flaky zinc powder of different particle sizes produced is high.

[0022] During the entire system operation, when the system pressure exceeds the set value, the pressure relief valve opens to reduce the pressure, and closes when the pressure returns to below the target value; if the system oxygen concentration exceeds the standard, the nitrogen replenishment valve will automatically open to replenish nitrogen until the oxygen concentration is lower than the target value. This automatic monitoring and adjustment mechanism ensures that the system operating environment is always in a safe and stable state, greatly reducing the risk of safety accidents caused by pressure fluctuations or changes in oxygen concentration, and allowing the production process to be carried out safely, continuously and stably.

[0023] The ball mill classification system greatly optimizes the production process by organically combining the traditional ball mill and the airflow classifier system, supplemented by the passivation treatment function. The originally complex and lengthy production process has been simplified, thereby effectively reducing the production cost. In terms of safety and reliability, except for closing the ball mill feeding port, all actions and interlocks in the overall operation process of the system are automatically controlled by the PLC program. This automated control method ensures the precise connection and stable operation of each link, avoiding the mistakes and uncertainties that may be caused by human operation. From the perspective of product quality, precise process control and passivation treatment functions make the product particle size classification more accurate, and the quality of flake zinc powder is greatly improved, which can better meet the market demand for high-quality flake zinc powder, enhance the competitiveness of the product in the market, and provide a strong technical guarantee for the efficient and safe production of flake zinc powder. In terms of production efficiency, due to the close connection of each link and the high degree of automation, the entire production cycle is greatly shortened, the output per unit time is significantly increased, and the production efficiency of the enterprise is further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The invention relates to a structural schematic diagram of a ball milling and grading system for producing flaky zinc powder.

[0025] Figure 2The present invention relates to a structural schematic diagram of a feed pipe of a ball mill classification system for producing flaky zinc powder (in a state where the movable rod is not extended).

[0026] Figure 3 The present invention relates to a structural schematic diagram of a ball mill classification system for producing flaky zinc powder with the sleeve omitted from the feeding pipe (in a state where the movable rod is not extended).

[0027] Figure 4 The present invention relates to a structural schematic diagram of a feed pipe of a ball mill classification system for producing flaky zinc powder (in a state where a movable rod is extended).

[0028] Figure 5 The present invention relates to a structural schematic diagram of a ball mill classification system for producing flaky zinc powder with the sleeve omitted from the feeding pipe (in a state where the movable rod is extended).

[0029] Figure 6 The invention relates to a structural schematic diagram of a movable rod of a ball mill classification system for producing flaky zinc powder.

[0030] In the picture

[0031] Negative pressure feeding Roots vacuum pump 1; feeding air outlet pipe 2; feeding air outlet valve 3; negative pressure feeding bag dust collector 4; feeding port 5; ball mill 6; first cooling water flow regulating valve 7; infrared temperature sensor 8; discharge pipe 9; vacuum valve 10; first-level classification host 11; first-level finished product discharge valve 12; second-level classification host 13; second-level finished product discharge valve 14; discharge bag dust collector 15; third-level finished product discharge valve 16; discharge return air pipe 17; discharge Roots vacuum pump 18; feeding and discharge valve 19; Discharge valve 20; pressure relief and emptying valve 21; nitrogen replenishing valve 22; return air valve 23; first pressure sensor 24; second pressure sensor 25; pipeline cooling heat exchanger 26; second cooling water flow regulating valve 27; temperature sensor 28; oxygen concentration sensor 29; feed pipe 30; pipeline body 31; socket section 32; sleeve 33; through hole 34; pressure strain gauge 35; driving electromagnet 36; moving ring 37; movable rod 38; prestressed bending part 39; impeller motor 40; grading impeller 41. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0033] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

[0034] like Figures 1 to 6As shown, a ball milling and grading system for producing flaky zinc powder comprises a negative pressure feeding Roots vacuum pump 1, a feeding air outlet pipe 2, a feeding air outlet valve 3, a negative pressure feeding bag dust collector 4, a ball mill 6, a discharge pipe 9, a vacuum valve 10, an airflow grading component, a discharge return air pipe 17, a discharge Roots vacuum pump 18, a feeding unloading valve 19, a discharge valve 20, a pressure relief and emptying valve 21, a nitrogen replenishing valve 22 and a return air valve 23, wherein one end of the feeding air outlet pipe 2 is connected to the negative pressure feeding Roots vacuum pump 1, and the other end is connected to the negative pressure feeding bag dust collector 4, and the feeding air outlet valve 3 is arranged on the feeding air outlet pipe 2. The side of the negative pressure loading bag dust collector 4 is provided with an inlet 5, and the bottom is connected to the ball mill 6. The loading and unloading valve 19 is arranged at the bottom of the negative pressure loading bag dust collector 4. One end of the discharge pipe 9 is connected to the ball mill 6, and the other end is connected to the airflow classification component. The vacuum valve 10 and the discharge valve 20 are arranged on the discharge pipe 9. One end of the discharge return air pipe 17 is connected to the airflow classification component, and the other end is connected to the ball mill 6. The discharge Roots vacuum pump 18, the pressure relief and emptying valve 21, the return air valve 23 and the nitrogen replenishment valve 22 are arranged on the discharge return air pipe 17 in sequence.

[0035] When a ball milling and grading system for producing flaky zinc powder in this embodiment is working, the first step is the feeding link. The negative pressure feeding Roots vacuum pump 1 works, so that the spherical zinc powder raw material and grinding aid are sucked in and transmitted through the feeding air outlet pipe 2. During this process, the feeding air outlet valve 3 can control the direction of the air flow. After the material reaches the negative pressure feeding bag dust collector 4, the gas-solid separation is carried out through the bag. The raw material and the aid enter the negative pressure feeding bag dust collector 4 through the feed port 5, and enter the ball mill 6 under the action of gravity. The feeding and unloading valve 19 controls the material flow entering the ball mill 6.

[0036] After the feeding is completed, the feeding port of the ball mill 6 is closed, and then the vacuum valve 10 is opened to use the vacuum system to extract the air in the system, and then the nitrogen replenishment valve 22 is opened to charge nitrogen, and this process is repeated several times until the pressure and oxygen concentration in the system reach the predetermined target values. Then the ball mill 6 is started, and grinding balls of a specific size and ratio are placed in the ball mill 6 in advance, and the material is ground.

[0037] When the grinding is finished, the nitrogen replenishing valve 22 is opened to inject nitrogen with a purity of 90%-99.9%, and the speed of the ball mill 6 is adjusted to a low speed, and the surface of the flaky zinc powder is passivated in an atmosphere with a trace oxygen concentration. The passivation treatment is intended to improve the performance of the flaky zinc powder, making it more stable during subsequent storage and use, and less prone to adverse chemical reactions such as oxidation. After the passivation treatment, the antioxidant capacity of the flaky zinc powder is significantly enhanced.

[0038] After the passivation is completed, the discharge valve 20, the return air valve 23 and the vacuum valve 10 are opened, and the gas is extracted again by the vacuum system, and then the nitrogen replenishment valve 22 is filled with high-purity nitrogen, and the pressure and oxygen concentration in the system are also alternated many times until the pressure and oxygen concentration in the system meet the requirements. Then the airflow classification component and the discharge Roots vacuum pump 18 are started, and the flaky zinc powder in the ball mill 6 is taken out by the airflow and enters the airflow classification component. In the airflow classification component, the flaky zinc powder is classified into finished products of different grades according to the particle size, and the finished products of each grade are discharged to the automatic vacuum packaging machine by alternating upper and lower unloading (locking air unloading) to complete the finished product packaging. After the dust-containing airflow passes through the bag gas-solid separation, the clean gas returns to the ball mill 6 through the discharge return air duct 17 and the discharge Roots vacuum pump 18, forming a cycle until all the materials in the ball mill 6 are discharged. Thanks to the precise classification function of the airflow classification component, the purity of the products of different particle sizes of flaky zinc powder produced is high.

[0039] During the operation of the entire system, when the system pressure exceeds the set value, the pressure relief valve 21 opens to reduce the pressure, and closes when the pressure returns to below the target value; if the system oxygen concentration exceeds the standard, the nitrogen replenishment valve 22 automatically opens to replenish nitrogen until the oxygen concentration is lower than the target value. This automatic monitoring and adjustment mechanism ensures that the system operating environment is always in a safe and stable state, greatly reducing the risk of safety accidents caused by pressure fluctuations or changes in oxygen concentration, so that the production process can be carried out safely, continuously and stably.

[0040] The ball mill classification system greatly optimizes the production process by organically combining the traditional ball mill 6 and the airflow classifier system, supplemented by the passivation treatment function. The originally complex and lengthy production process has been simplified, thereby effectively reducing the production cost. In terms of safety and reliability, except for closing the feeding port of the ball mill 6, all actions and interlocks in the overall operation process of the system are automatically controlled by the PLC program. This automated control method ensures the precise connection and stable operation of each link, avoiding the mistakes and uncertainties that may be caused by human operation. From the perspective of product quality, precise process control and passivation treatment functions make the product particle size classification more accurate, and the quality of flaky zinc powder is greatly improved, which can better meet the market demand for high-quality flaky zinc powder, enhance the competitiveness of the product in the market, and provide strong technical guarantees for the efficient and safe production of flaky zinc powder. In terms of production efficiency, due to the close connection of each link and the high degree of automation, the entire production cycle is greatly shortened, the output per unit time is significantly increased, and the production efficiency of the enterprise is further improved.

[0041] The airflow classification component includes a primary classification host 11, a secondary classification host 13 and a discharge bag dust collector 15, the primary classification host 11 and the secondary classification host 13 are provided with an impeller motor 40 and a classification impeller 41, the primary classification host 11 is provided with a primary finished product discharge valve 12, the secondary classification host 13 is provided with a secondary finished product discharge valve 14, the discharge bag dust collector 15 is provided with a tertiary finished product discharge valve 16, the discharge return air duct 17 is connected to the discharge bag dust collector 15, and the discharge duct 9 is connected to the primary classification host 11. The impeller motor 40 and the classification impeller 41 equipped on the primary classification host 11 and the secondary classification host 13 work together to accurately screen and classify the flaky zinc powder according to the particle size. During operation, the flaky zinc powder in the ball mill 6 enters the first-level classification host 11 through the discharge pipe 9. Under the action of the specific airflow generated by the rotation of the classification impeller 41 driven by the impeller motor 40, the flaky zinc powder with larger particle size is separated first, and discharged and collected through the first-level finished product discharge valve 12, completing the first-level particle size screening of finished products. Then, the remaining zinc powder enters the second-level classification host 13, where the particle size is further subdivided through a similar principle, and the zinc powder that meets the corresponding standards is collected through the second-level finished product discharge valve 14. The dusty airflow that still exists after the two-level classification enters the discharge bag dust collector 15. Through the gas-solid separation effect of the bag, the clean gas returns to the ball mill 6 through the discharge return air duct 17 for continued recycling, and the separated flaky zinc powder with finer particle size is collected through the third-level finished product discharge valve 16, finally realizing the accurate classification of the flaky zinc powder into finished products of different particle size grades.

[0042] Furthermore, a first pressure sensor 24 is provided between the secondary classification host 13 and the discharge bag filter 15, and a second pressure sensor 25 is provided on the discharge return air duct 17, and the second pressure sensor 25 is provided between the discharge bag filter 15 and the discharge Roots vacuum pump 18. The first pressure sensor 24 is located between the secondary classification host 13 and the discharge bag filter 15, and can monitor the air pressure of this link in real time to ensure the normal transmission of zinc powder and gas-solid separation. The second pressure sensor 25 is on the discharge return air duct 17, which can monitor the gas circulation pressure, and can provide timely feedback in case of abnormality, so that the system can be adjusted in time.

[0043] One end of the ball mill 6 is provided with a first cooling water flow regulating valve 7 and an infrared temperature sensor 288. During grinding, the ball mill 6 generates heat due to friction, and the infrared temperature sensor 288 accurately monitors the temperature change of the ball mill 6. Once the temperature deviates from the target range, it transmits a signal to the control system. At this time, the first cooling water flow regulating valve 7 controls the cooling water flow by adjusting the opening according to the instruction, so that the temperature of the ball mill 6 is always stable within the appropriate target range, which not only ensures the normal progress of the chemical reaction and physical grinding inside the ball mill 6, avoids the problems of raw material denaturation and equipment damage caused by high temperature, but also ensures the production quality of flaky zinc powder and the continuity of the production process.

[0044] The discharge return air duct 17 is provided with a duct cooling heat exchanger 26, and the duct cooling heat exchanger 26 is provided with a second cooling water flow regulating valve 27. The gas in the discharge return air duct 17 will carry heat during the circulation process. If the heat accumulates, it may affect the stable operation of the entire system and the quality of the flaky zinc powder. The duct cooling heat exchanger 26 can cool the hot air flow passing through, and the second cooling water flow regulating valve 27 can accurately control the cooling water flow in and out of the duct cooling heat exchanger 26 by adjusting its opening, thereby realizing fine control of the cooling effect of the heat exchanger.

[0045] The discharge return air duct 17 is provided with a temperature sensor 28 and an oxygen concentration sensor 29. The temperature sensor 28 can sense the system temperature in real time. Once the temperature is abnormal, the temperature can be stabilized by adjusting the cooling water regulating valve. The oxygen concentration sensor 29 can accurately monitor the oxygen concentration. When the oxygen concentration exceeds the standard, the nitrogen replenishment operation can be triggered in time. The two together ensure the safe and stable operation of the system.

[0046] A feed pipe 30 is provided at one end of the ball mill 6, and the discharge return air duct 17 is connected to the feed pipe 30. The feed pipe 30 includes a pipe body 31, a sleeve 33, a driving electromagnet 36, a moving ring 37 and a plurality of movable rods 38. A sleeve section 32 is provided on the pipe body 31, and the driving electromagnet 36 is provided at the end of the sleeve section 32. The moving ring 37 is sleeved on the sleeve section 32. The moving ring 37 is made of a magnet. One end of the movable rod 38 is connected to the moving ring 37. A plurality of movable rods 38 are evenly distributed around the circumference of the sleeve section 32. A prestressed bending portion 39 is provided on the movable rod 38 so that the movable rod 38 is bent without external force. The sleeve 33 is sleeved on the sleeve section 32. A movable cavity is provided between the sleeve 33 and the sleeve section 32 for the moving ring 37 to move. A plurality of through holes 34 are provided on the sleeve 33 for the plurality of movable rods 38 to pass through. During passivation, the driving electromagnet 36 acts on the movable ring 37 made of magnets to make it move axially along the sleeve section 32. When the movable ring 37 moves outward, it drives the movable rod 38 to extend. Due to the prestressed bending portion 39, the movable rod 38 forms a closed space. When oxygen and nitrogen pass through this space, they are cut and dispersed by multiple movable rods 38. Oxygen and nitrogen can be fully mixed, and oxygen is evenly distributed, which effectively improves the uniformity of the passivation effect, makes the surface passivation treatment of flaky zinc powder more consistent, and ensures the stability of product quality. When the movable ring 37 moves in the opposite direction, the movable rod 38 is straightened and completely retracted into the through hole 34 under the guidance of the through hole 34 of the sleeve 33, avoiding obstruction or interference to the pipeline airflow, ensuring the smoothness of the airflow of the entire production system at different stages.

[0047] A pressure strain gauge 35 is provided in the through hole 34. During the passivation process, when the driving electromagnet 36 controls the movement of the moving ring 37 so that the movable rod 38 extends, the multiple movable rods 38 form a closed space by means of the bending part, and this space will play a role in receiving the zinc powder. The pressure strain gauge 35 located in the through hole 34 can keenly sense the receiving force. When the passivation is not yet completed, as the passivation continues to advance, each time the movable rod 38 extends to receive the zinc powder, the weight characteristics received are also in dynamic change due to the constant change in the state of the zinc powder. Once the passivation process is over, the relevant properties of the zinc powder tend to be stable, and at this time, the weight characteristics received by the movable rod 38 when it is extended will present a stable state. This design provides a reliable basis for judging the degree of passivation. In the past, there was often a lack of accurate and intuitive ways to judge whether the passivation was completed. With the help of the pressure strain gauge 35 to monitor the changes in weight characteristics, the operator can clearly and accurately know the progress of the passivation.

[0048] The driving electromagnets 36 are provided in an even number, and the even number of driving electromagnets 36 surround the sleeve section 32 uniformly. By setting half of the electromagnets to one polarity and the other half to the opposite polarity, the push-pull action of the moving ring 37 can be effectively achieved. When the moving ring 37 needs to move outward, the electromagnets of a specific polarity are energized to generate a magnetic field, which interacts with the magnetism of the moving ring 37 to generate an outward thrust; and when the moving ring 37 needs to move inward, the electromagnets of the other polarity are energized to generate a pulling force in the opposite direction, thereby accurately controlling the axial movement of the moving ring 37 on the sleeve section 32.

[0049] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "include..." or "comprise..." do not exclude the existence of other elements in the process, method, article or terminal device including the elements. In addition, in this article, "greater than", "less than", "exceed" and the like are understood to exclude the number itself; "above", "below", "within" and the like are understood to include the number itself.

[0050] The above description of the embodiments is to facilitate the understanding and use of the present invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to the embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. A ball mill classification system for producing flaky zinc powder, characterized in that: It includes a negative pressure feeding Roots vacuum pump, a feeding air outlet pipe, a feeding air outlet valve, a negative pressure feeding bag dust collector, a ball mill, a discharge pipe, a vacuum valve, an air flow classification component, a discharge return air pipe, a discharge Roots vacuum pump, a feeding unloading valve, a discharge valve, a pressure relief and emptying valve, a nitrogen replenishing valve and a return air valve. One end of the feeding air outlet pipe is connected to the negative pressure feeding Roots vacuum pump, and the other end is connected to the negative pressure feeding bag dust collector. The feeding air outlet valve is arranged on the feeding air outlet pipe. The negative pressure feeding bag dust collector A feeding port is provided on the side, and the bottom is connected to the ball mill. The loading and unloading valve is arranged at the bottom of the negative pressure loading bag dust collector. One end of the discharge pipe is connected to the ball mill, and the other end is connected to the airflow classification component. The vacuum valve and the discharge valve are arranged on the discharge pipe. One end of the discharge return air pipe is connected to the airflow classification component, and the other end is connected to the ball mill. The discharge Roots vacuum pump, pressure relief and emptying valve, return air valve and nitrogen replenishment valve are arranged on the discharge return air pipe in sequence.

2. A ball milling and classifying system for producing flaky zinc powder according to claim 1, characterized in that: The airflow classification component includes a primary classification host, a secondary classification host and a discharge bag dust collector. The primary classification host and the secondary classification host are provided with impeller motors and classification impellers. A primary finished product discharge valve is provided under the primary classification host, a secondary finished product discharge valve is provided under the secondary classification host, and a third finished product discharge valve is provided under the discharge bag dust collector. The discharge return air duct is connected to the discharge bag dust collector, and the discharge duct is connected to the primary classification host.

3. A ball milling and classifying system for producing flaky zinc powder according to claim 2, characterized in that: A first pressure sensor is provided between the secondary classification host and the discharge bag filter.

4. A ball milling and classifying system for producing flaky zinc powder according to claim 2, characterized in that: A second pressure sensor is provided on the discharge return air duct, and the second pressure sensor is provided between the discharge bag filter and the discharge Roots vacuum pump.

5. The ball milling and classifying system for producing flaky zinc powder according to claim 1, characterized in that: A first cooling water flow regulating valve and an infrared temperature sensor are arranged at one end of the ball mill.

6. A ball milling and classifying system for producing flaky zinc powder according to claim 1, characterized in that: A pipeline cooling heat exchanger is provided on the discharge return air pipeline, and a second cooling water flow regulating valve is provided on the pipeline cooling heat exchanger.

7. A ball milling and classifying system for producing flaky zinc powder according to claim 1, characterized in that: The discharge return air duct is provided with a temperature sensor and an oxygen concentration sensor.

8. The ball milling and classifying system for producing flaky zinc powder according to claim 1, characterized in that: A feed pipe is provided at one end of the ball mill, and the discharge return air duct is connected to the feed pipe. The feed pipe includes a pipe body, a sleeve, a driving electromagnet, a moving ring and a plurality of movable rods. A sleeve section is provided on the pipe body, and the driving electromagnet is provided at the end of the sleeve section. The moving ring is sleeved on the sleeve section. The moving ring is made of a magnet. One end of the movable rod is connected to the moving ring. A plurality of movable rods are evenly distributed around the circumference of the sleeve section. A prestressed bending portion is provided on the movable rod so that the movable rod bends without the action of external force. The sleeve is sleeved on the sleeve section, and a movable cavity is provided between the sleeve and the sleeve section for the moving ring to move. A plurality of through holes are provided on the sleeve for the plurality of movable rods to pass through.

9. A ball milling and classifying system for producing flaky zinc powder according to claim 8, characterized in that: A pressure strain gauge is arranged in the through hole.

10. A ball milling and classifying system for producing flaky zinc powder according to claim 8, characterized in that: The driving electromagnets are provided in an even number, and the even number of driving electromagnets uniformly surround the sleeve section.

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