Screening device for titanium powder for injection molding

Abstract

The utility model relates to a screening device for titanium powder for injection molding. The screening device comprises a straight-row screen, a vibration motor, a straight-row screen powder collecting tank, an airflow classifier powder adding tank, an electromagnetic vibration feeder and an airflow classifier. A discharge port of the straight discharge sieve is connected with a feed port of the straight discharge sieve powder collecting tank; a discharge port of the direct discharge sieve powder collecting tank is connected with a feed port of the airflow classifier powder adding tank; the vibration motors are arranged on the outer sides of the circumferences of the bottoms of the straight discharging sieves correspondingly. A discharging port of the airflow classifier powder adding tank is connected with a feeding port of the airflow classifier through the electromagnetic vibration feeder. According to the utility model, the direct discharge sieve, the grader and the mixer are connected in series, so that the problems of high oxygen content, low screening efficiency and the like of the existing screening equipment can be effectively solved; by adding the primary grading wheel, 0-5 mu m fine powder is controlled to enter the dust remover, so that the fine powder yield is improved, and meanwhile, the service life of a cloth bag filter element in the dust remover is prolonged. The device has the advantages of high screening precision, high powder collecting rate, high screening efficiency, low oxygen content and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of metal powder preparation, in particular to a screening device for titanium powder used for injection molding. Background Art

[0002] Titanium and its alloys have poor machinability. Traditional machining methods require expensive equipment and low efficiency, significantly increasing processing costs. Titanium parts that can be machined are often simple in structure, and due to limitations in machining methods, most cannot achieve designs that maximize the material's performance. Against this backdrop, Metal Injection Molding (MIM), with its advantages of high raw material utilization and low cost for mass production of small, complex-shaped titanium products, has become an ideal machining process for titanium and its alloys.

[0003] The metal powder injection molding process typically includes material preparation, injection molding, debinding, sintering, and post-processing. When the powder particle size is too large, powder-binder separation can easily occur during the injection process. For the MIM industry, titanium powder particle sizes typically range from 0-25μm, 0-40μm, and 0-45μm.

[0004] With the continuous expansion of MIM applications in product areas such as 3C, sports and outdoor equipment, and medical equipment, especially the preference for MIM titanium alloy technology in 3C electronics, watches, and mobile phones, the industry's demand for ultrafine spherical titanium powder and feed products has reached an unprecedented scale. Current factors restricting the mass application of titanium powder in the 3C field are the low yield of domestic aerosol manufacturers producing titanium powder in the 0-25μm range, resulting in high prices. At the same time, domestic 0-25μm titanium powder production capacity is limited and cannot meet the mass production needs of the 3C field. To reduce costs, domestic injection molding manufacturers have expanded the particle size range of injection molding titanium powder from 0-25μm to 0-40 / 45μm.

[0005] At present, the screening process for spherical titanium powder with a diameter of 0-40 / 45μm for injection molding is: vibrating screen deslagging - airflow classifier classification - V-type mixer mixing. Some 0-5μm powder will enter the dust collector of the classifier and adhere to the surface of the bag filter, resulting in a low yield of 0-40 / 45μm powder and a short filter replacement cycle. At the same time, the powder classified by the airflow classifier needs to be transferred to the mixer for mixing. The 0-40- / 45μm powder is easily oxidized and burned during the transfer process, and the particle size of the mixed product of the V-type mixer fluctuates greatly, which affects the subsequent injection molding process.

[0006] Therefore, how to improve the powder yield of 0-40 / 45μm powder and accurately control the powder particle size distribution requires further improvement based on the existing screening equipment. Summary of the Invention

[0007] In view of the above problems, the purpose of the present invention is to provide a screening device for titanium powder for injection molding, which can effectively solve the problems of low powder yield for injection molding and large fluctuation in product particle size.

[0008] The technical solutions adopted in this utility model are as follows:

[0009] The utility model proposes a screening device for titanium powder for injection molding, comprising a straight-line screen, a vibration motor, a straight-line screen powder collecting tank, an air flow classifier powder adding tank, an electromagnetic vibration feeder and an air flow classifier; the discharge port of the straight-line screen is connected to the feed port of the straight-line screen powder collecting tank; the discharge port of the straight-line screen powder collecting tank is connected to the feed port of the air flow classifier powder adding tank; the vibration motors are respectively arranged on the outer side of the circumference of the bottom of the straight-line screen; the discharge port of the air flow classifier powder adding tank is connected to the feed port of the air flow classifier through the electromagnetic vibration feeder.

[0010] Furthermore, a first valve is provided between the in-line screen and the in-line screen powder collecting tank; a second valve is provided between the in-line screen powder collecting tank and the airflow classifier powder adding tank.

[0011] Furthermore, the air flow classifier includes a dust collector, a first-level classifying tank, a second-level classifying tank, a third-level classifying tank, a first-level classifying wheel, a second-level classifying wheel, a third-level classifying wheel, a first-level powder collecting tank, a second-level powder collecting tank and a third-level powder collecting tank; the first-level powder collecting tank is arranged at the bottom of the first-level classifying tank; the second-level powder collecting tank is arranged at the bottom of the second-level classifying tank; the third-level powder collecting tank is arranged at the bottom of the third-level classifying tank; the first-level classifying wheel is arranged at the top of the first-level classifying tank; the second-level classifying wheel is arranged at the top of the second-level classifying tank; the third-level classifying wheel is arranged at the top of the third-level classifying tank; the feed port of the first-level classifying tank is connected to the discharge port of the air flow classifier powder adding tank through an electromagnetic vibrating feeder; the first-level classifying wheel is connected to the feed port of the second-level classifying tank; the second-level classifying wheel is connected to the feed port of the third-level classifying tank; the third-level classifying wheel is connected to the feed port of the dust collector.

[0012] Furthermore, the bottom discharge port of the secondary powder collecting tank is provided with a third valve; the bottom discharge port of the tertiary powder collecting tank is provided with a fourth valve.

[0013] Furthermore, a double-pile mixer is provided between the bottoms of the secondary powder collecting tank and the tertiary powder collecting tank; the bottom discharge ports of the secondary powder collecting tank and the tertiary powder collecting tank are respectively connected to the double-pile mixer through pipelines.

[0014] Furthermore, a fifth valve is provided at the feed inlet pipe of the double-piled mixer.

[0015] Furthermore, an oxygen concentration sensor is provided inside the inline screen.

[0016] Furthermore, the mesh specification of the in-line screen is 60 mesh or 100 mesh.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The utility model adds a set of classifying wheels to the traditional air classifier, which reduces the 0-5μm powder entering the dust collector to a minimum, further improves the yield of 0-45μm powder, and effectively prolongs the service life of the bag filter element inside the dust collector.

[0019] 2. The utility model directly obtains 0-40 / 45 μm powder products by hoisting the powder collecting tank of the powder making furnace to the three-dimensional screening device, reducing the previous transportation, mixing and batching processes required after powder screening; it can realize the automation of screening, improve work efficiency, greatly improve the efficiency of alloy powder production, and reduce the workload of workers.

[0020] 3. The utility model also has the function of controlling the oxygen content in the whole screening process, and the oxygen content of the 0-40 / 45μm powder product is reduced from the current 1000ppm to below 800ppm.

[0021] 4. The utility model does not have a transfer process, which prevents the air inside the factory and impurities on the surface of the transfer barrel from entering the powder, causing a decrease in powder purity. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0023] Figure 2 The particle size distribution diagram of TC4 powder with a size of 0-45 μm is obtained by screening the device of the utility model;

[0024] Figure 3 The particle size distribution diagram of 0-45μm TC4 powder screened by the existing air classifier.

[0025] Among them, the figure marks are: 1-inline screen feed port; 2-inline screen; 3-vibration motor; 4-inline screen powder collecting tank; 5-air flow classifier powder adding tank; 6-electromagnetic vibrating feeder; 7-first-stage grading wheel; 8-second-stage grading wheel; 9-third-stage grading wheel; 10-first-stage powder collecting tank; 11-second-stage powder collecting tank; 12-third-stage powder collecting tank; 13-double-pile mixer; 14-first valve; 15-second valve; 16-third valve; 17-fourth valve; 18-fifth valve; 19-dust collector; 20-first-stage grading tank; 21-second-stage grading tank; 22-third-stage grading tank. DETAILED DESCRIPTION

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] It should be noted that, in the description of the present invention, the terms "upper", "lower", "top", "bottom", "one side", "the other side", "left", "right", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not mean that the device or element must have a specific orientation, be constructed and operated in a specific orientation.

[0028] See attached Figure 1-3 The utility model proposes a screening device for titanium powder for injection molding, which includes a straight-line screen 2, a vibration motor 3, a straight-line screen powder collecting tank 4, an airflow classifier powder adding tank 5, an electromagnetic vibrating feeder 6 and an airflow classifier. The feed port 1 of the straight-line screen is directly connected to the discharge port of the powder collecting tank of the powder making furnace, and the discharge port of the straight-line screen feed 2 is connected to the feed port of the straight-line screen powder collecting tank 4; the discharge port of the straight-line screen powder collecting tank 4 is connected to the feed port of the airflow classifier powder adding tank 5; the vibration motors 3 are respectively arranged on the outer side of the circumference of the bottom of the straight-line screen 2, and at least two are arranged; the discharge port of the airflow classifier powder adding tank 5 is connected to the feed port of the airflow classifier through the electromagnetic vibrating feeder 6.

[0029] In this embodiment, an oxygen concentration sensor is provided inside the in-line screen 2 for collecting and controlling the oxygen content inside the in-line screen; the mesh specification of the in-line screen 2 is 60 mesh or 100 mesh; the in-line screen 2 performs primary screening under the action of the vibration motor 3.

[0030] The air flow classifier includes a dust collector 19, a first-level classifying wheel 7, a second-level classifying wheel 8, a third-level classifying wheel 9, a first-level powder collecting tank 10, a second-level powder collecting tank 11, a third-level powder collecting tank 12, a first-level classifying tank 20, a second-level classifying tank 21 and a third-level classifying tank 22; the first-level powder collecting tank 10 is arranged at the bottom of the first-level classifying tank 20; the second-level powder collecting tank 11 is arranged at the bottom of the second-level classifying tank 21; the third-level powder collecting tank 12 is arranged at the bottom of the third-level classifying tank 22; the first-level classifying wheel 7 is arranged at the top of the first-level classifying tank 20; the second-level classifying wheel 8 is arranged at the top of the second-level classifying tank 21; the third-level classifying wheel 9 is arranged at the top of the third-level classifying tank 22; the feed port of the first-level classifying tank 20 is connected to the discharge port of the air flow classifier powder adding tank 5 through an electromagnetic vibrating feeder 6; the first-level classifying wheel 7 is also connected to the feed port of the second-level classifying tank 21; the second-level classifying wheel 8 is also connected to the feed port of the third-level classifying tank 22; the third-level classifying wheel 9 is also connected to the feed port of the dust collector 19.

[0031] A dual-pile mixer 13 is provided between the bottoms of the secondary powder collecting tank 11 and the tertiary powder collecting tank 12. The bottom outlets of the secondary powder collecting tank 11 and the tertiary powder collecting tank 12 are connected to the feed inlet of the dual-pile mixer 13 via pipes. The dual-pile mixer 13 is provided with a pressure gauge, an air inlet valve, and an air outlet valve.

[0032] In this embodiment, the in-line screen powder collecting tank 4 , the airflow classifier powder adding tank 5 , the secondary powder collecting tank 11 , the tertiary powder collecting tank 12 and the double-pile mixer 13 are all provided with manual exhaust valves.

[0033] The feeding and powder collection between the three devices of the in-line screen 2, the air flow classifier and the double-pile mixer 13 are separated by valves and can work independently of each other. The specific setting method is: a first valve 14 is provided between the in-line screen 2 and the in-line screen powder collecting tank 4; a second valve 15 is provided between the in-line screen powder collecting tank 4 and the air flow classifier powder adding tank 5; a third valve 16 is provided at the bottom discharge port of the secondary powder collecting tank 11; a fourth valve 17 is provided at the bottom discharge port of the tertiary powder collecting tank 12; and a fifth valve 18 is provided at the feed port pipe of the double-pile mixer 13.

[0034] The working principle of the present invention is as follows: taking TC4 powder as an example of feed, the powder collecting tank of the powder making furnace is connected to the feed port 1 of the straight-discharge screen, the bottom valve of the powder collecting tank of the powder making furnace is opened, and the powder passes through the screen of the straight-discharge screen 2 to remove slag to obtain 0-250μm powder, and the powder enters the straight-discharge screen powder collecting tank 4 from the first valve 14 at the bottom of the straight-discharge screen 2, and the manual exhaust valve of the air flow classifier powder adding tank 5 is opened to ensure that the pressure in the tank is normal pressure to prevent the internal air pressure of the air flow classifier powder adding tank 5 from causing the powder in the straight-discharge screen powder collecting tank 4 to be back-sprayed into the straight-discharge screen 2 or to circulate downward poorly when the second valve 15 is opened; after the second valve 15 is opened, the 0-250μm powder enters the air flow classifier powder collecting tank 5, and then the second valve 15 is closed, and the air flow classifier is opened to start grading; at this time, the straight-discharge screen 2 can continue to carry out slag removal operations; entering the grading The powder of the machine is classified by air flow and the powder of 45-250μm is collected under the first-stage powder collecting tank 10, the powder of 15-45μm is collected under the second-stage powder collecting tank 11, and the powder of 0-15μm is collected under the third-stage powder collecting tank 12; the fifth valve 18 is opened, and the air inside the double-pile mixer 13 is replaced three times with high-purity argon gas; the manual exhaust valve of the second-stage powder collecting tank 11 is opened to normal pressure, the third valve 16 under the second-stage powder collecting tank 11 is opened, and the powder of 15-45μm enters the double-pile mixer 13, then the third valve 16 is closed, the manual exhaust valve of the third-stage powder collecting tank 12 is opened to normal pressure, the fourth valve 17 is opened, and the powder of 0-15μm enters the double-pile mixer 13, then the fourth valve 17 and the fifth valve 18 are closed, and the double-pile mixer 13 starts mixing. When the mixing is completed, the fifth valve 18 is made to face vertically downward. The particle size distribution of the collected 0-45μm TC4 powder is shown as follows: Figure 2 As shown, D10 is 9.25 μm, D50 is 23.7 μm, D90 is 44.2 μm, and the yield of 0-45 μm TC4 powder is about 40.6%.

[0035] The existing air flow classifier is used to screen and mix the materials to obtain 0-45 μm TC4 powder. Figure 3 As shown, the powder D10 is 11.2μm, D50 is 25.2μm, D90 is 43.5μm, and the 0-45μm TC4 powder yield is 35.3%.

[0036] When the particle size of the feed TC4 powder is the same, compared with the existing air flow classifier, the D10 and D50 of the 0-45μm TC4 powder obtained by the device of the utility model are smaller, indicating that less powder enters the dust collector. At the same time, the yield of 0-45μm TC4 powder using the device of the utility model is higher.

[0037] Matters not described in detail in this utility model are known technologies.

[0038] The embodiments described above are merely descriptions of preferred implementation methods of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A screening device for titanium powder for injection molding, characterized in that: The device comprises an inline screen, a vibration motor, a powder collecting tank of the inline screen, a powder adding tank of an airflow classifier, an electromagnetic vibration feeder and an airflow classifier; the discharge port of the inline screen is connected to the feed port of the powder collecting tank of the inline screen; the discharge port of the powder collecting tank of the inline screen is connected to the feed port of the powder adding tank of the airflow classifier; the vibration motors are respectively arranged on the outer circumference of the bottom of the inline screen; the discharge port of the powder adding tank of the airflow classifier is connected to the feed port of the airflow classifier through the electromagnetic vibration feeder; The air flow classifier includes a dust collector, a first-level classifying tank, a second-level classifying tank, a third-level classifying tank, a first-level classifying wheel, a second-level classifying wheel, a third-level classifying wheel, a first-level powder collecting tank, a second-level powder collecting tank and a third-level powder collecting tank; the first-level powder collecting tank is arranged at the bottom of the first-level classifying tank; the second-level powder collecting tank is arranged at the bottom of the second-level classifying tank; the third-level powder collecting tank is arranged at the bottom of the third-level classifying tank; the first-level classifying wheel is arranged at the top of the first-level classifying tank; the second-level classifying wheel is arranged at the top of the second-level classifying tank; the third-level classifying wheel is arranged at the top of the third-level classifying tank; the feed port of the first-level classifying tank is connected to the discharge port of the air flow classifier powder adding tank through an electromagnetic vibrating feeder; the first-level classifying wheel is connected to the feed port of the second-level classifying tank; the second-level classifying wheel is connected to the feed port of the third-level classifying tank; the third-level classifying wheel is connected to the feed port of the dust collector.

2. The screening device for titanium powder for injection molding according to claim 1, characterized in that: A first valve is provided between the in-line screen and the in-line screen powder collecting tank; a second valve is provided between the in-line screen powder collecting tank and the airflow classifier powder adding tank.

3. The screening device for titanium powder for injection molding according to claim 1, characterized in that: The bottom discharge port of the secondary powder collecting tank is provided with a third valve; the bottom discharge port of the tertiary powder collecting tank is provided with a fourth valve.

4. The screening device for titanium powder for injection molding according to claim 3, characterized in that: A double-pile mixer is provided between the bottoms of the secondary powder collecting tank and the tertiary powder collecting tank; the bottom discharge ports of the secondary powder collecting tank and the tertiary powder collecting tank are respectively connected to the double-pile mixer through pipelines.

5. The screening device for titanium powder for injection molding according to claim 4, characterized in that: A fifth valve is provided at the feed inlet pipe of the double-piled mixer.

6. The screening device for titanium powder for injection molding according to claim 1, characterized in that: An oxygen concentration sensor is provided inside the in-line screen.

7. The screening device for titanium powder for injection molding according to claim 1, characterized in that: The mesh specification of the in-line screen is 60 mesh or 100 mesh.

Images