Neodymium-iron-boron magnetic powder tank cleaning system and cleaning method thereof

Abstract

The invention relates to the technical field of neodymium iron boron magnetic powder processing equipment, in particular to a neodymium iron boron magnetic powder tank cleaning system which comprises a tank conveying device, a tank cleaning device and a waste powder collecting device. The material tank cleaning device comprises a supporting frame, a material tank butt joint device, an air exhaust connecting pipe, an up-down moving air pipe and a moving adjusting mechanism device. Wherein a cavity is defined by the supporting frame, a material tank conveying device is arranged at the bottom of the cavity, a material tank enters or leaves the cavity operationally through the material tank conveying device, and the movable adjusting device is fixedly arranged in the supporting frame; the material tank butt joint device is fixedly arranged in the middle of the cavity, and the material tank butt joint device is hermetically connected to the inlet end of the material tank entering the cavity through a hoop; the air exhaust connecting pipe is fixedly arranged at the upper part of the charging bucket butting device; automatic conveying of the charging buckets is achieved through the charging bucket conveying device, manual carrying is not needed, and the cleaning efficiency is greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of neodymium iron boron magnetic powder processing equipment, and particularly relates to a neodymium iron boron magnetic powder tank cleaning system and a cleaning method thereof. BACKGROUND

[0002] In the production of neodymium iron boron magnets, the magnetic powder tank is a core container for storing and transferring magnetic powder, and the cleanliness and the atmosphere in the tank directly affect the product quality: on the one hand, the residual magnetic powder in the tank needs to be completely removed before replacing a new batch of magnetic powder, otherwise the residual powder mixed into the new powder will cause uneven composition of the magnetic powder, leading to deviation of the magnetic permeability, remanence and other performances of the magnet, and reducing the product qualification rate; on the other hand, the neodymium iron boron magnetic powder is sensitive to oxygen, and the oxygen content in the tank needs to be reduced to below 100 ppm after cleaning to avoid oxidation of the new powder and ensure the performance of the magnet.

[0003] At present, the industry generally adopts manual cleaning of the tank, and the process is as follows: the tank is turned over by using a suspension device to make the tank opening downward, after the butterfly valve is opened, the residual powder is shaken off by knocking the tank wall, and then a straight pipe gas pipe is inserted to flush the remaining fine powder with high-pressure gas.

[0004] Although this method can remove the basic residual powder, it has a large safety hazard: when cleaning, the tank is open, the residual powder (especially fine powder) is exposed to the air, and is affected by knocking vibration and airflow disturbance, and is easy to cause fire due to increased contact area and local temperature reaching the self-ignition point; raw material waste: the neodymium iron boron magnetic powder contains rare earth elements, which are scarce and have high cost, but in manual cleaning, the residual powder directly falls off without a collection device, and the recoverable residual powder is wasted; low utilization rate of the tank: cleaning and oxygen removal are independent processes, and after cleaning, the tank needs to be transferred to a special device for a long time to pass inert gas to remove oxygen.

[0005] In view of the above problems, the present application designs a neodymium iron boron magnetic powder tank cleaning system and a matching method, which realizes the safety of tank cleaning, the efficiency of residual powder recovery, and the integration of cleaning and oxygen removal through structure optimization and process integration, to achieve the cleaning goal of safety, effectiveness, environmental protection and saving. SUMMARY

[0006] The purpose of the present application is to provide a neodymium iron boron magnetic powder tank cleaning system and a cleaning method thereof in view of the deficiencies in the prior art.

[0007] To achieve the above purpose, the technical solution adopted by the present application is as follows:

[0008] A neodymium iron boron magnetic powder tank cleaning system, comprising: a tank conveying device, a tank cleaning device, and a waste powder collecting device;

[0009] The tank cleaning device comprises: a support frame, a tank docking device, an air extraction connecting pipe, an up-down moving gas pipe, and a moving adjusting mechanism device;

[0010] The support frame is provided with a cavity, the bottom of the cavity is provided with a canister conveying device, the canister is operatively connected to the canister conveying device to enter or exit the cavity, and the moving adjusting device is fixedly arranged in the support frame;

[0011] The canister docking device is fixedly arranged in the middle of the cavity, the canister docking device is sealingly connected to the inlet end of the canister entering the cavity through a clamp, and the suction connection pipe is fixedly arranged at the upper portion of the canister docking device;

[0012] The upper and lower moving air pipe is arranged in the moving adjusting device, the outlet end of the upper and lower moving air pipe penetrates the lumen of the suction connection pipe, and the outlet end of the upper and lower moving air pipe is arranged inside the can cavity of the canister, the inlet end of the upper and lower moving air pipe is in communication with the high-pressure gas pipeline through the high-pressure gas interface, the side wall of the suction connection pipe is fixedly provided with a suction branch pipe, the suction branch pipe is in communication with the lumen of the suction connection pipe and the waste powder collecting device, and the upper portion of the suction connection pipe is fixedly provided with a rubber sealing ring, and the outlet end of the upper and lower moving air pipe penetrates the rubber sealing ring;

[0013] The outlet end of the upper and lower moving air pipe is also fixedly provided with a pneumatic rotary nozzle.

[0014] Further, the moving adjusting device comprises a fixed support fixedly arranged at the upper portion of the support frame, a screw rod adjusting mechanism arranged at one side of the fixed support, a connecting plate fixedly arranged at one side of the nut seat of the screw rod adjusting mechanism, and a second motor fixedly arranged at one side of the connecting plate;

[0015] The screw rod adjusting mechanism is used to drive the nut seat to move up and down, thereby driving the connecting plate and the upper and lower moving air pipe to move up and down synchronously;

[0016] The upper and lower moving air pipe comprises a rotary joint mounted in the connecting plate, an air pipe flexible tube connected to the inlet end of the rotary joint, and an air pipe rigid tube connected to the outlet end of the rotary joint;

[0017] The outlet of the high-pressure gas interface is in communication with the air pipe flexible tube, and the pneumatic rotary nozzle is fixed to the outlet end of the air pipe rigid tube; the upper portion of the air pipe rigid tube is provided with a plurality of gear teeth in the circumferential direction, the output end of the second motor is provided with a transmission gear, and the transmission gear is in transmission connection with the gear teeth of the air pipe rigid tube through a synchronous belt.

[0018] Further, it further comprises an auxiliary powder collector detachably arranged on the top outer wall of the canister;

[0019] The auxiliary powder collector comprises an electromagnet and a fixed plate;

[0020] The fixed plate is matched with the outer wall of the canister, and the electromagnet is fixedly arranged on the side of the fixed plate away from the canister; the coil of the electromagnet is electrically connected with an external power supply and a control switch through a wire.

[0021] Further, the waste powder collecting device comprises a filter tank, an air suction fan, and a dust collecting tank;

[0022] The bottom of the filter tank is provided with a dust outlet, the dust outlet is detachably connected with the inlet of the dust collecting tank, and a switch valve is fixedly arranged on the dust outlet;

[0023] The top of the filter tank is provided with an air suction port, and the air suction port is connected with the suction port of the air suction fan in a pipeline mode;

[0024] The sidewall of the filter tank is provided with a dust inlet, and the dust inlet is connected with the outlet of the suction branch pipe;

[0025] A filter screen is fixedly arranged in the tank cavity of the filter tank, and the filter screen is located at the upper portion of the dust inlet.

[0026] Further, the sidewall of the support frame is fixedly provided with an operation box;

[0027] The operation box is provided with a PLC controller and a control panel electrically connected with the PLC controller, and the control panel is provided with a tank conveying start-stop button, an air suction fan start-stop knob and an air suction speed adjusting button, and a mobile air pipe lifting control rocker.

[0028] Further, the high-pressure gas in the high-pressure gas pipeline is pure argon or nitrogen.

[0029] A cleaning method using the neodymium-iron-boron magnetic powder tank cleaning system as described above, comprising the following steps:

[0030] Step one, placing the tank to be cleaned on the tank conveying device, starting the tank conveying device through the operation box, and conveying the tank to be cleaned to below the tank docking device;

[0031] Step two, sealingly connecting the inlet end of the tank to be cleaned with the outlet of the tank docking device by using a clamp, arranging the dust collecting tank at the dust outlet of the filter tank, opening the switch valve on the filter tank, and connecting the high-pressure gas interface to the high-pressure gas pipeline;

[0032] Step three, driving the up-and-down mobile air pipe to move downward by the screw rod adjusting mechanism of the mobile adjusting mechanism through the operation box, so that the pneumatic rotary nozzle extends into the interior of the tank to be cleaned and is positioned at a distance of 5cm-10cm from the tank bottom of the tank to be cleaned; opening the valve of the high-pressure gas pipeline, so that the pneumatic rotary nozzle sprays high-pressure gas flow, and the second motor of the mobile adjusting mechanism drives the air pipe hard tube to rotate through the synchronous belt, so as to drive the pneumatic rotary nozzle to rotate synchronously; after 10s-15s of continuous spraying, starting the air suction fan through the operation box, and continuing to spray for 10s-30s; during the process, the gas-powder mixture in the tank to be cleaned enters the filter tank through the air suction branch pipe for separation and collection;

[0033] Step 4: Control the screw adjustment mechanism of the moving adjustment mechanism through the control box to drive the up and down moving air pipe to move the pneumatic rotary nozzle upward by 5cm to 10cm, and continue spraying for 10s to 30s.

[0034] Repeat the above process until the pneumatic rotary nozzle moves to the outlet of the cleaning tank;

[0035] Subsequently, the screw adjustment mechanism of the moving adjustment mechanism drives the up and down moving air pipe to reset the pneumatic rotary nozzle to a distance of 5cm to 10cm from the bottom of the tank being cleaned.

[0036] Step 5: After repeating Step 4 5-20 times, close the valve of the high-pressure gas pipeline and the exhaust fan, and release the clamp connection between the cleaned tank and the tank docking device; remove the cleaned tank through the tank conveying device, and convey the next tank to be cleaned to the docking position, then return to Step 1.

[0037] Furthermore, it also includes: Step zero, detecting the average particle size (SMD) of the residual magnetic powder in the tank to be cleaned; if the average particle size (SMD) of the residual magnetic powder in the tank to be cleaned is less than 2.0 μm, then:

[0038] In step one, the auxiliary powder collector is installed on the upper part of the material tank and close to the tank opening;

[0039] In step three, current is intermittently applied to the electromagnet: each time the current is applied for 3 to 5 seconds and then de-energized for 5 to 8 seconds, until step three is completed.

[0040] Furthermore, in step three, the pressure of pure argon or pure nitrogen in the high-pressure gas pipeline is greater than 0.6 MPa.

[0041] Furthermore, an electromagnet can generate a magnetic field greater than 1.2T when energized. Compared with existing technologies, the present invention, employing the above technical solution, has the following technical advantages:

[0042] This invention can effectively and safely clean magnetic powder tanks, avoiding problems such as fires that may occur during traditional tank cleaning processes. Furthermore, the technology provided by this invention can effectively recover residual powder from the tanks, saving rare earth raw materials. Simultaneously, this invention can also remove oxygen from the tanks while cleaning, resulting in an oxygen content of less than 100 ppm inside the tanks after cleaning. This avoids the lengthy oxygen removal process required after traditional tank cleaning, improving the effective utilization rate of the magnetic powder tanks and saving inert gas. Using pure argon or pure nitrogen as high-pressure gas can prevent oxidation and deterioration of the magnetic powder during cleaning and avoid problems such as fires that may occur during traditional tank cleaning, ensuring the quality of magnetic powder recovery. Attached Figure Description

[0043] Figure 1 Structure diagram of the whole of the application;

[0044] Figure 2 Structure diagram of the front of the mobile adjusting mechanism device, the up-and-down moving air pipe, and the air extraction connecting pipe in the application;

[0045] Figure 3 Structure diagram of the shaft side of the mobile adjusting mechanism device, the up-and-down moving air pipe, and the air extraction connecting pipe in the application;

[0046] Figure 4 Structure diagram of the front of the filter tank in the application;

[0047] Figure 5 Structure diagram of the shaft side of the air extraction connecting pipe and the air extraction branch pipe in the application;

[0048] Figure 6 Structure diagram of the shaft side of the up-and-down moving air pipe and the air-driven rotary spray head in the application;

[0049] Figure 7 Structure diagram of the auxiliary dust collector in the application;

[0050] The reference signs in the drawings are as follows:

[0051] 1, tank conveying device; 2, tank cleaning device; 21, support frame; 22, tank butt joint device; 23, air extraction connecting pipe; 24, up-and-down moving air pipe; 25, air-driven rotary spray head; 26, mobile adjusting mechanism device; 261, fixed support; 262, screw rod adjusting mechanism; 2621, nut seat; 263, connecting plate; 264, second motor; 265, rotary joint; 266, air pipe flexible pipe; 267, air pipe rigid pipe; 268, synchronous belt; 27, air extraction branch pipe; 3, waste powder collecting device; 31, filter tank; 311, powder discharge port; 312, air extraction port; 32, air extraction fan; 33, filter screen; 34, on-off valve; 4, tank; 5, dust collecting tank; 6, auxiliary dust collector; 61, electromagnet; 62, fixed plate; 7, operation box. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the application.

[0053] It should be noted that the embodiments in the application and the features in the embodiments can be combined with each other without conflict. It should be noted that the embodiments in the application and the features in the embodiments can be combined with each other without conflict.

[0054] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0055] Example 1

[0056] like Figure 1 As shown, this embodiment provides a neodymium iron boron magnetic powder tank cleaning system, including: a tank conveying device 1, a tank cleaning device 2, and a waste powder collection device 3;

[0057] The material tank conveying device 1 is used to carry the material tank 4 to be cleaned or already cleaned. It can drive the material tank 4 to move along a preset path, so that the material tank 4 can automatically enter or leave the cavity of the material tank cleaning device 2 without manual handling.

[0058] The tank cleaning device 2 includes a support frame 21, a tank docking device 22, an air extraction connection pipe 23, an up-and-down moving air pipe 24, a pneumatic rotary nozzle 25, and a moving adjustment mechanism 26.

[0059] The support frame 21 forms a cavity by enclosure; the bottom of the cavity is aligned with the material tank conveying device 1 to ensure that the material tank 4 can enter the docking position in the cavity; the moving adjustment mechanism 26 is fixedly set in the support frame 21 to provide the power basis for the movement of the vertically moving air pipe 24.

[0060] The material tank docking device 22 is fixed in the middle of the cavity. When the material tank 4 reaches the docking position, it is sealed to the inlet end of the material tank 4 by means of a clamp to prevent the gas-powder mixture from leaking from the docking point when the high-pressure airflow is purged, thus ensuring the sealing effect.

[0061] The suction connection pipe 23 is fixed to the upper part of the material tank docking device 22. On the one hand, it provides a through channel for the vertically moving air pipe 24. On the other hand, it is connected to the waste powder collection device 3 through the suction branch pipe 27 on the side wall to form a conveying channel for the gas-powder mixture. A rubber sealing ring 28 is fixedly provided on the upper part of the suction connection pipe 23. The outlet end of the vertically moving air pipe 24 passes through the through hole of the rubber sealing ring 28, which can further enhance the sealing performance and prevent the gas-powder mixture from overflowing.

[0062] The movable adjustment mechanism 26 includes: a fixed bracket 261 fixedly mounted on the upper part of the support frame 21, a screw adjustment mechanism 262 mounted on one side of the fixed bracket 261, a connecting plate 263 fixedly mounted on one side of the nut seat 2621 of the screw adjustment mechanism 262, and a second motor 264 fixedly mounted on one side of the connecting plate 263; the screw adjustment mechanism 262 can drive the nut seat 2621 to move up and down, thereby driving the connecting plate 263 and the vertical moving air pipe 24 to move up and down synchronously, realizing the height adjustment of the pneumatic rotary nozzle 25; the second motor 264 provides power for the rotation of the pneumatic rotary nozzle 25.

[0063] The up-and-down moving air pipe 24 comprises a rotary joint 265 installed in the connecting plate 263, an air pipe hose 266 connected to the inlet end of the rotary joint 265, and an air pipe hard tube 267 connected to the outlet end of the rotary joint 265; the outlet end of the up-and-down moving air pipe 24 penetrates the lumen of the air extraction connecting pipe 23 and extends into the inside of the material tank 4, and the inlet end is connected to the high-pressure gas pipeline through the high-pressure gas interface; the outer surface of the upper part of the air pipe hard tube 267 is provided with a plurality of gear teeth in the circumferential direction, the output end of the second motor 264 is provided with a transmission gear, and the transmission gear is in transmission connection with the gear teeth of the air pipe hard tube 267 through a synchronous belt 268; when the second motor 264 is started, the air pipe hard tube 267 and the pneumatic rotary nozzle 25 can be driven to rotate synchronously; the pure argon gas or pure nitrogen gas with a pressure greater than 0.6 MPa is conveyed in the lumen of the up-and-down moving air pipe 24, so that the oxidation of the magnetic powder can be avoided.

[0064] The pneumatic rotary nozzle 25 is fixedly arranged at the outlet end of the air pipe hard tube 267 and rotates synchronously when the high-pressure gas flow is sprayed, so that the inner wall of the material tank 4 can be swept at 360° without dead angle, the residual magnetic powder can be stripped from the tank wall, and the cleaning thoroughness can be improved.

[0065] The auxiliary powder collector 6 is detachably arranged on the outer wall of the top of the material tank 4 and close to the tank opening, and is composed of a fixed plate 62 and an electromagnet 61; the fixed plate 62 is matched with the outer wall of the material tank 4, so that the auxiliary powder collector 6 can be stably arranged; when the electromagnet 61 is electrified, a magnetic field with a magnetic field intensity greater than 1.2T can be generated, so that the fine-grained magnetic powder (the average powder particle size SMD is less than 2.0μm) rising with the gas flow in the cleaning process can be adsorbed, and the fine powder recovery rate can be improved; the coil of the electromagnet 61 is electrically connected with the external power supply and the control switch through a wire.

[0066] The waste powder collecting device 3 comprises a filter tank 31, an air extraction fan 32, a dust collecting tank 5 and a filter screen 33.

[0067] The dust inlet of the sidewall of the filter tank 31 is connected with the air extraction branch pipe 27, so as to receive the gas-powder mixture from the material tank 4; the dust discharge port 311 at the bottom of the filter tank 31 is detachably connected with the dust collecting tank 5, so that the dust collecting tank 5 can be replaced after being filled; the air extraction port 312 at the top of the filter tank 31 is connected with the air extraction fan 32, so that a negative pressure is formed under the action of the air extraction fan 32, and the gas-powder mixture is guided into the filter tank 31.

[0068] The filter screen 33 is fixed in the tank cavity of the filter tank 31 and located at the upper part of the dust inlet, so that the magnetic powder in the gas-powder mixture can be blocked, the gas passes through the filter screen 33 and is discharged through the air extraction port 312, and the gas-powder separation is realized.

[0069] The switch valve 34 is fixed on the dust discharge port 311, so that the separated dust in the filter tank 31 can fall into the dust collecting tank 5 when the switch valve 34 is opened, and the external air can be prevented from entering the filter tank 31 to affect the negative pressure environment when the dust collecting tank 5 is replaced.

[0070] The suction fan 32 forms a negative pressure in the suction connection pipe 23, the suction branch pipe 27 and the filter tank 31 through suction, provides power for the flow of the gas-powder mixture, and ensures that the dust generated during the cleaning process can be timely pumped to the waste powder collecting device 3.

[0071] The operation box 7 is fixed to the side wall of the support frame 21 and is used for controlling the operation of the whole system. The PLC controller inside is electrically connected with each executing component. The tank conveying start-stop button on the control panel controls the start and stop of the tank conveying device 1. The suction fan start-stop knob and the suction speed adjusting button control the opening and closing and the suction speed of the suction fan 32. The moving air pipe lifting control rocker controls the action of the screw adjusting mechanism 262 of the moving adjusting mechanism 26, and then drives the up-and-down moving air pipe 24 to lift, so as to realize the linkage operation of each component and simplify the operation process.

[0072] As a preferred embodiment, the switch valve 34 is a butterfly valve.

[0073] As a preferred embodiment, a scale line is formed on the support rod of the fixed support 261 along the height direction of the support rod.

[0074] Example 2

[0075] The present example 2 provides a cleaning method of the neodymium-iron-boron magnetic powder tank cleaning system as described in example 1, and the specific steps are as follows:

[0076] Step zero: detect the average powder particle size SMD of the residual magnetic powder in the tank 4 to be cleaned:

[0077] If the average powder particle size SMD of the residual magnetic powder is greater than or equal to 2.0 μm, directly enter step one;

[0078] If the average powder particle size SMD of the residual magnetic powder is less than 2.0 μm, the auxiliary powder collector 6 needs to be added in the subsequent steps (see steps one and three), and the electromagnet 61 in the auxiliary powder collector 6 generates a magnetic field greater than 1.2 T when energized.

[0079] Step one: place the tank 4 to be cleaned on the tank conveying device 1. If it is determined in step zero that the auxiliary powder collector 6 needs to be used, install the auxiliary powder collector 6 on the upper part of the tank 4 close to the tank opening.

[0080] Start the tank conveying device 1 through the operation box 7, and convey the tank 4 to be cleaned to below the tank butt joint device 22.

[0081] Step two: seal and connect the inlet end of the tank 4 to be cleaned with the outlet of the tank butt joint device 22 by using a clamp; set the dust collecting tank 5 at the dust discharge port 311 of the filter tank 31, and open the switch valve 34 on the filter tank 31.

[0082] Connect the high-pressure gas interface of the up-and-down moving gas pipe 24 to the high-pressure gas pipeline.

[0083] Step three: drive the nut base 2621 of the screw rod adjusting mechanism 262 to move downward by operating the operation box 7, drive the connecting plate 263 and the up-and-down moving gas pipe 24 to move downward synchronously, make the pneumatic rotating nozzle 25 extend into the inside of the material tank 4 to be cleaned, and position at 5 cm from the tank bottom of the material tank 4 to be cleaned;

[0084] Open the valve of the high-pressure gas pipeline, make the pneumatic rotating nozzle 25 spray high-pressure gas flow (the pressure of pure argon or pure nitrogen in the high-pressure gas pipeline is greater than 0.6 MPa), and start the second motor 264 at the same time, the transmission gear at the output end of the second motor 264 drives the gas pipe hard pipe 267 to rotate through the synchronous belt 268, drive the pneumatic rotating nozzle 25 to rotate synchronously;

[0085] After the pneumatic rotating nozzle 25 continuously sprays for 10 s, start the air suction fan 32 through the operation box 7, and continue to spray for 10 s;

[0086] In this process: if the auxiliary powder collector 6 needs to be used according to the judgment in step zero, intermittently pass current to the electromagnet 61 (each time, pass current for 3 s, and then cut off the current for 5 s, until step three is finished); the gas-powder mixture in the material tank 4 to be cleaned enters the filter tank 31 to be separated and collected through the air suction branch pipe 27.

[0087] Step four: drive the nut base 2621 of the screw rod adjusting mechanism 262 to move upward by operating the operation box 7, drive the connecting plate 263, the up-and-down moving gas pipe 24 and the pneumatic rotating nozzle 25 to move upward synchronously by 5 cm, continue to spray for 10 s; repeat the process of “moving upward by 5 cm, spraying for 10 s” until the pneumatic rotating nozzle 25 moves to the outlet of the material tank 4 to be cleaned;

[0088] Then drive the nut base 2621 of the screw rod adjusting mechanism 262 to move downward, drive the up-and-down moving gas pipe 24 and the pneumatic rotating nozzle 25 to reset to 5 cm from the tank bottom of the material tank 4 to be cleaned.

[0089] Step five: after repeating step four for 5 times, close the valve of the high-pressure gas pipeline, the second motor 264 and the air suction fan 32; release the clamp connection between the cleaned material tank 4 and the material tank butt joint device 22;

[0090] Remove the cleaned material tank 4 through the material tank conveying device 1, and convey the next material tank 4 to be cleaned to the butt joint position, return to step one for processing.

[0091] Example 3

[0092] This embodiment is based on the cleaning system of Example 1 and the cleaning method of Example 2. For the internal residual magnetic powder with an average powder particle size SMD = 3.2 μm (meeting the "SMD ≥ 2.0 μm" judgment condition in Step Zero of Example 2, without the need to use the tank 4 of the auxiliary powder collector 6), the detection process of Step Zero and subsequent operations are refined to verify the effectiveness of the cleaning system and cleaning method in this scenario, as follows:

[0093] Step Zero: Detect the average powder particle size SMD of the residual magnetic powder in the tank 4 to be cleaned:

[0094] The residual magnetic powder in the tank 4 to be cleaned is detected by a laser particle size analyzer. The result after detection is that the average powder particle size SMD of the residual magnetic powder is ≥ 2.0 μm, meeting the judgment standard of "no need to use the auxiliary powder collector 6" in Step Zero of Example 2, and entering the subsequent cleaning steps.

[0095] Step One: Place the tank 4 to be cleaned stably on the conveyor belt of the tank conveying device 1, start the device by operating the "tank conveying start-stop button" of the operation box 7, and convey the tank 4 along the preset path of the conveyor belt to the position directly below the tank docking device 22 in the cavity of the support frame 21 without manual handling.

[0096] Step Two: Sealing docking: use high-strength stainless steel clamps (inner diameter adapted to the tank opening of the tank 4 and the outlet of the tank docking device 22) to tightly connect the tank opening of the tank 4 with the outlet end of the tank docking device 22; after connection, apply soap water to the docking gap and observe for the absence of air bubbles to confirm full sealing (to avoid air entering the tank during cleaning or leakage of gas-powder mixture);

[0097] Dismountably connect the dust collection tank 5 to the dust outlet 311 at the bottom of the filter tank 31 through the flange, and rotate the switch valve 34 at the dust outlet 311 clockwise to open it; connect the high-pressure gas interface at the inlet end of the up-down moving air pipe 24 to the pure nitrogen gas pipeline, and adjust the pipeline pressure to 0.7 MPa (meeting the requirement of "high-pressure gas pressure > 0.6 MPa" in Example 2, ensuring the blowing power).

[0098] Step Three: Positioning of the spray head: open the butterfly valve at the tank opening of the tank 4, control the screw rod adjustment mechanism 262 of the moving adjustment mechanism 26 to drive the nut seat 2621 to move downward by operating the "moving air pipe lifting control joystick" of the operation box 7, and extend the up-down moving air pipe 24 downward, so that the pneumatic rotary spray head 25 fixed to the outlet end of the air pipe hard tube 267 extends into the tank until the scale shows that the spray head is 8 cm away from the tank bottom, and then stop lifting;

[0099] Slowly open the pipeline valve of high-pressure gas interface, the pneumatic rotating nozzle 25 sprays high-pressure pure nitrogen gas, and the second motor 264 starts to rotate the air pipe hard tube 267 through the synchronous belt 268, which drives the nozzle to rotate synchronously for 10s (to make the residual powder preliminarily separate from the tank wall); then the suction fan 32 is started through the operation box 7 to continue to blow for 20s, and the mixture of "nitrogen gas and residual powder" in the tank enters the filter tank 31 under the action of negative pressure through the suction branch pipe 27.

[0100] Step four: layered cleaning: control the screw rod adjusting mechanism 262 of the moving adjusting mechanism 26 to drive the nut seat 2621 to move upward by 8cm through the operation box 7, drive the up-down moving air pipe 24 and the pneumatic rotating nozzle 25 to move upward by 8cm, keep the high-pressure nitrogen gas spraying and the suction fan running, and continue to clean for 20s; repeat the operation of "moving upward by 8cm and cleaning for 20s" until the nozzle moves to the tank opening of the material tank 4;

[0101] Nozzle reset and repetition: control the screw rod adjusting mechanism 262 to drive the nut seat 2621 to move downward, drive the up-down moving air pipe 24 and the pneumatic rotating nozzle 25 to reset to a distance of 10cm from the tank bottom, and repeat the above "layered cleaning" process again, a total of 10 times.

[0102] Step five: sequentially close the suction fan 32, the pipeline valve of the high-pressure gas interface and the second motor 264; loosen the clamp between the material tank 4 and the material tank docking device 22, start the material tank conveying device 1, and convey the cleaned material tank 4 to the cleaned area;

[0103] Effect detection (verify cleaning quality and efficiency):

[0104] Oxygen content detection: the oxygen content analyzer is flushed with high-purity nitrogen gas (to remove residual air in the analyzer), and the probe is inserted into the tank through the material tank 4 inlet under the protection of pure nitrogen gas, and the test result is 85ppm (<100ppm, meeting the anti-oxidation requirement of subsequent powder loading, without the need for additional oxygen removal process);

[0105] Residual powder detection: open the material tank 4 inlet and observe with the naked eye, there is no visible magnetic powder residue in the tank; use transparent tape to paste the tank bottom, tank body and tank opening inner wall respectively, and there is no magnetic powder attached after tearing off;

[0106] Efficiency detection: from the start of the material tank 4 to the completion of the cleaning and removal, the total time is 5min.

[0107] Example 4

[0108] This embodiment is based on the cleaning system of Example 1 and the cleaning method of Example 2, and two sets of parallel experiments (Experiment No. 1: SMD = 1.9 μm, without auxiliary powder collector; Experiment No. 2: SMD = 1.9 μm, with auxiliary powder collector) are set up to verify the necessity of "SMD < 2.0 μm, auxiliary powder collector 6 is required" in Step Zero of Example 2, as follows:

[0109] Both sets of experiments use the same size tank 4, and the high pressure gas is pure nitrogen. The difference between the two sets of experiments is the "magnetic powder particle size" and "whether to use auxiliary powder collector 6".

[0110] The oxygen content detection and residual powder detection methods are the same as those of Example 3.

[0111] Experiment No. 1:

[0112] Clean the tank storing SMD = 1.9 μm magnetic powder (without auxiliary powder collector 6, corresponding to Example 2 "SMD < 2.0 μm");

[0113] Step one: Place the tank 4 in the tank conveying device 1 and convey it to the bottom of the tank docking device 22;

[0114] Step two: seal and connect the tank 4 and the tank docking device 22 with a clamp, dock the dust collection tank 5 and open the switch valve 34, and connect the high pressure gas interface to the pure nitrogen pipeline (the pressure of the high pressure gas is 0.6 MPa);

[0115] Step three: control the lead screw adjusting mechanism 262 of the moving adjusting mechanism 26 to make the pneumatic rotary nozzle 25 8 cm away from the tank bottom, open the nitrogen valve and blow for 10 s, then start the air exhaust fan 32, and at the same time the second motor 264 drives the air pipe hard tube 267 to rotate and synchronously rotate the nozzle through the synchronous belt 268, and continue to blow for 20 s;

[0116] Step four: repeat "control the lead screw adjusting mechanism 262 to drive the nozzle to move upward by 8 cm and clean for 20 s" until the nozzle reaches the tank opening, and then control the lead screw adjusting mechanism 262 to drive the nozzle to reset to 10 cm away from the tank bottom and repeat again, a total of 10 times;

[0117] Step five: close the valve, second motor 264 and fan, release the clamp and convey the tank 4 to the cleaned area.

[0118] Effect detection: oxygen content: 90 ppm (<100 ppm, up to standard); no residual powder in the tank, and a small amount of magnetic powder is found on the adhesive tape, which is caused by the strong molecular adhesion of some fine powder close to 2.0 μm to the tank wall, which is difficult to completely peel off by high pressure airflow alone.

[0119] Experiment No. 2:

[0120] Cleaning the tank storing SMD = 1.9 μm magnetic powder (with auxiliary powder collector, corresponding to Example 2 "SMD < 2.0 μm");

[0121] Step one: Place the tank 4 in the tank conveying device 1 and convey it under the tank docking device 22; according to the requirements of Example 2, the auxiliary powder collector 6 is attached to the upper part of the tank 4 near the tank opening through the fixing plate 62 (matching the curvature of the tank wall), and is fixed with rubber bands (the magnetic end of the electromagnet 61 faces the tank);

[0122] Step two: consistent with Experiment No. 1 (high-pressure gas pressure 0.6 MPa);

[0123] Step three: in addition to the same operation as Experiment No. 1 (control the lead screw adjusting mechanism 262 to position the spray head, open the nitrogen valve, start the second motor 264 to drive the spray head to rotate, and start the air exhaust fan 32), according to the requirements of Example 2, intermittent current is supplied to the electromagnet 61: each time the power is on for 5 s and off for 5 s, until the end of this step (during this process, it needs to be explained that the electromagnet 61 generates a magnetic field of >1.2 T, which adsorbs fine powder and agglomerates into large powder clusters, and after power off, the agglomerated powder clusters are removed with the negative pressure air flow);

[0124] Step four: consistent with Experiment No. 1 (cumulative repetition 10 times);

[0125] Step five: close the valve, the second motor 264 and the fan, remove the auxiliary powder collector 6, release the clamp and convey the tank 4 to the cleaned area.

[0126] Effect detection: oxygen content: 90 ppm (<100 ppm); residual powder: no residue visible, tape detection shows no magnetic powder, and no magnetic powder is due to the magnetic field of the auxiliary powder collector 6 solving the fine powder adhesion problem: fine powder (SMD = 1.9 μm) has strong molecular force and light mass, and is difficult to be removed by air flow alone, and the magnetic field can agglomerate fine powder into large powder clusters, which can be efficiently pumped to the filter tank 31 by negative pressure.

[0127] Experimental conclusion Through comparison of the two groups of experiments, it can be proved that:

[0128] For SMD≥2.0 μm magnetic powder (such as 3.2 μm), the cleaning method of Example 2 (without auxiliary powder collector) can achieve basic cleaning requirements, but fine powder close to 2.0 μm is easy to remain;

[0129] For SMD < 2.0 μm fine powder (such as 1.9 μm), the auxiliary powder collector 6 needs to be installed according to the requirements of Example 2 and intermittent current is supplied, so as to completely solve the fine powder adhesion problem;

[0130] In the two scenarios, the oxygen content in the tank after cleaning is less than 100 ppm, and the whole process is based on the full sealing structure of the system, and there is no risk of spontaneous combustion of residual powder, verifying the adaptability and safety of the cleaning method of example 2.

[0131] In summary, the present application can effectively and safely clean the magnetic powder tank, avoid the problems such as fire that may occur in the traditional tank cleaning process, and effectively recover the residual powder in the tank, save rare earth raw materials, and at the same time, the present application can also perform oxygen removal on the tank while cleaning the magnetic powder tank, and the oxygen content in the tank after cleaning is less than 100 ppm, thereby avoiding the long oxygen removal process after traditional tank cleaning, improving the effective utilization rate of the magnetic powder tank, and saving inert gas, using pure argon or pure nitrogen as high-pressure gas, which can prevent the oxidation and deterioration of the magnetic powder during the cleaning process, and avoid the problems such as fire that may occur in the traditional tank cleaning process, and ensure the quality of magnetic powder recovery.

[0132] The above of the present application are only the preferred embodiments of the present application, and not limit the embodiments and protection scope of the present application, and for those skilled in the art, it should be realized that any equivalent replacement and obvious change obtained by applying the content of the present application should be included in the protection scope of the present application.

Claims

1. A cleaning system for a neodymium iron boron magnetic powder tank, characterized in that, include: The material tank conveying device (1), the material tank cleaning device (2), and the waste powder collection device (3) are included. The tank cleaning device (2) includes: a support frame (21), a tank docking device (22), an air extraction connection pipe (23), an up-and-down moving air pipe (24), and a moving adjustment mechanism device (26); The supporting frame (21) is enclosed to form a cavity, and the bottom of the cavity is provided with the material tank conveying device (1). The material tank (4) is operatively entered or left the cavity through the material tank conveying device (1). The moving adjustment device (26) is fixedly installed in the supporting frame (21). The material tank docking device (22) is fixedly disposed in the middle of the cavity, and the material tank docking device (22) is sealed to the inlet end of the material tank (4) entering the cavity by a clamp; the air extraction connection pipe (23) is fixedly disposed on the upper part of the material tank docking device (22); The vertical moving air pipe (24) is installed in the moving adjustment device (26). The outlet end of the vertical moving air pipe (24) passes through the cavity of the suction connecting pipe (23), and the outlet end of the vertical moving air pipe (24) is installed inside the cavity of the material tank (4). The inlet end of the vertical moving air pipe (24) is connected to the high-pressure gas pipeline through the high-pressure gas interface. A suction branch pipe (27) is fixedly installed on the side wall of the suction connecting pipe (23). The suction branch pipe (27) connects the cavity of the suction connecting pipe (23) to the waste powder collection device (3). A rubber sealing ring is fixedly installed on the upper part of the suction connecting pipe (23). The outlet end of the vertical moving air pipe (24) passes through the cavity of the material tank (4). The outlet end of the vertically movable air pipe (24) is also fixedly equipped with a pneumatic rotary nozzle (25).

2. The NdFeB magnetic powder tank cleaning system according to claim 1, characterized in that, The movable adjustment device (26) includes: a fixed bracket (261) fixedly disposed on the upper part of the support frame (21), a screw adjustment mechanism (262) disposed on one side of the fixed bracket (261), a connecting plate (263) fixedly disposed on one side of the nut seat (2621) of the screw adjustment mechanism (262), and a second motor (264) fixedly disposed on one side of the connecting plate (263); The lead screw adjustment mechanism (262) is used to drive the nut seat (2621) to move up and down, thereby driving the connecting plate (263) and the vertical moving air pipe (24) to move up and down synchronously. The vertically movable air tube (24) includes: a rotary joint (265) installed in the connecting plate (263), an air tube hose (266) connected to the inlet end of the rotary joint (265), and an air tube rigid tube (267) connected to the outlet end of the rotary joint (265). The outlet of the high-pressure gas interface is connected to the air hose (266), and the pneumatic rotary nozzle (25) is fixed to the outlet end of the air tube (267). The upper outer surface of the air tube (267) is provided with several gear teeth in the circumferential direction. The output end of the second motor (264) is provided with a transmission gear. The transmission gear is connected to the gear teeth of the air tube (267) through a synchronous belt (268).

3. The NdFeB magnetic powder tank cleaning system according to claim 1, characterized in that, Also includes: An auxiliary powder collector (6) is detachably installed on the top outer wall of the material tank (4); The auxiliary dust collector (6) includes an electromagnet (61) and a fixing plate (62); The fixing plate (62) matches the outer wall of the material tank (4), and the electromagnet (61) is fixedly provided on the side of the fixing plate (62) away from the material tank (4); the coil of the electromagnet (61) is electrically connected to an external power source and a control switch through a wire.

4. The NdFeB magnetic powder tank cleaning system according to claim 1, characterized in that, The waste powder collection device (3) includes: a filter tank (31), an exhaust fan (32), and a dust collection tank (5); The bottom of the filter tank (31) is provided with a dust outlet (311), and the dust outlet (311) is detachably connected to the inlet of the dust collection tank (5). A switch valve (34) is also fixedly provided on the dust outlet (311). The top of the filter tank (31) is provided with an air extraction port (312), which is connected to the suction port pipe of the air extraction fan (32). The filter tank (31) has a dust inlet on its side wall, and the dust inlet is connected to the outlet of the suction branch pipe (27). A filter screen (33) is fixedly installed in the cavity of the filter tank (31), and the filter screen (33) is located above the dust inlet.

5. The NdFeB magnetic powder tank cleaning system according to claim 1, characterized in that, An operating box (7) is fixedly installed on the side wall of the support frame (21); The operation box (7) has a PLC controller and a control panel electrically connected to the PLC controller; the control panel is equipped with: a material tank conveying start / stop button, an exhaust fan start / stop knob and an exhaust speed adjustment button, and a moving air pipe lifting control rocker.

6. The NdFeB magnetic powder tank cleaning system according to claim 1, characterized in that, The high-pressure gas inside the high-pressure gas pipeline is pure argon or nitrogen.

7. A cleaning method using the NdFeB magnetic powder tank cleaning system as described in any one of claims 1-6, characterized in that the steps include... include: Step 1: Place the tank (4) to be cleaned on the tank conveying device (1), start the tank conveying device (1) through the operation box (7), and convey the tank (4) to be cleaned to the bottom of the tank docking device (22). Step 2: Use the clamp to seal the inlet end of the material tank (4) to be cleaned to the outlet of the material tank docking device (22); place the dust collection tank (5) at the dust outlet (311) of the filter tank (31), and open the switch valve (34) on the filter tank (31), while connecting the high-pressure gas interface to the high-pressure gas pipeline. Step 3: Control the screw adjustment mechanism (262) of the moving adjustment mechanism (26) through the operation box (7) to drive the up-down moving air pipe (24) to move downward, so that the pneumatic rotary nozzle (25) extends into the interior of the material tank (4) to be cleaned and is positioned 5cm to 10cm away from the bottom of the material tank (4) to be cleaned; open the valve of the high-pressure gas pipeline, so that the pneumatic rotary nozzle (25) sprays high-pressure airflow, and at the same time, the second motor (264) of the moving adjustment mechanism (26) drives the air pipe hard pipe (267) to rotate through the synchronous belt (268), driving the pneumatic rotary nozzle (25) to rotate synchronously; after spraying for 10s to 15s, start the exhaust fan (32) through the operation box (7) to continue spraying for 10s to 30s; during this process, the gas-powder mixture in the material tank (4) to be cleaned enters the filter tank (31) through the exhaust branch pipe (27) for separation and collection; Step 4: Control the screw adjustment mechanism (262) of the moving adjustment mechanism (26) through the operation box (7) to drive the up and down moving air pipe (24) to drive the pneumatic rotary nozzle (25) to move upward by 5cm to 10cm, and continue spraying for 10s to 30s; Repeat the above process until the pneumatic rotary nozzle (25) moves to the outlet of the material tank (4) during cleaning; Subsequently, the upper and lower moving air pipe (24) is driven by the screw adjustment mechanism (262) of the moving adjustment mechanism (26) to drive the pneumatic rotary nozzle (25) to return to a distance of 5cm to 10cm from the bottom of the material tank (4) being cleaned; Step 5: After repeating Step 4 5-20 times, close the valve of the high-pressure gas pipeline and the exhaust fan (32), release the clamp connection between the cleaned tank (4) and the tank docking device (22); remove the cleaned tank (4) through the tank conveying device (1), and convey the next tank (4) to be cleaned to the docking position, returning to Step 1.

8. The cleaning method according to claim 7, characterized in that, It also includes: Step zero, detecting the average particle size (SMD) of the residual magnetic powder in the tank (4) to be cleaned; if the average particle size (SMD) of the residual magnetic powder in the tank to be cleaned is less than 2.0 μm, then: In step one, the auxiliary powder collector (6) is installed on the upper part of the material tank (4) and close to the tank opening; In step three, current is intermittently supplied to the electromagnet (61): each time the current is supplied for 3 to 5 seconds and then de-energized for 5 to 8 seconds, until step three ends.

9. The cleaning method according to claim 7, characterized in that, In step three, the pressure of pure argon or pure nitrogen in the high-pressure gas pipeline is greater than 0.6 MPa.

10. The cleaning method according to claim 8, characterized in that, When the electromagnet (61) is energized, it can generate a magnetic field greater than 1.2T.

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