A spheroidizing device for fusible powder

Abstract

The present invention relates to a spheroidizing device for meltable powder material, characterized in that it comprises a melt spheroidizing device (B) and a preheating device (A) connected to the lower part thereof; the melt spheroidizing device (B) comprises a spheroidizing cylinder (9) in which an inner cylinder (10) is arranged; an anti-turbulence device (7) is arranged at the lower part, a heating device (11) is arranged at the outer periphery of the bottom part, an electromagnetic induction heating coil (14) is arranged at the outer periphery of the upper part, and a cooling jacket (15) is arranged at the outer periphery of the upper part; the preheating device (A) comprises a heating cylinder (3) in which a screw propeller (2) is arranged, a heating device (5) is arranged at the outer periphery, a feed hopper (1) is arranged at one end, and a gas replacement device (C) is arranged on the feed pipe. Advantages of the present invention: the device is small in size, simple in structure, easy to control, and has low energy consumption; it can spheroidize organic polymer material powder, inorganic non-metallic material powder, etc., and the obtained sphere has a higher surface finish and is more compact.

Description

Technical Field

[0001] The invention relates to the field of spheroidization of powder materials, and in particular to a spheroidization device for fusible powder materials. Background Art

[0002] High temperature fusible powder is a powder material with a particle size ranging from a few microns to several hundred microns that can be melted at high temperatures.

[0003] At present, there are two main methods for spheroidizing spherical powders: physical method and chemical method. Physical methods mainly include flame method and plasma method; chemical methods mainly include gas phase method and liquid phase method. Flame method is a process in which alkane gas is used as fuel and air, oxygen-enriched air or oxygen is used as combustion-supporting gas. The powder is melted, spheroidized, cooled, shaped and collected by burning flame and high-temperature airflow. It has high energy consumption, large equipment footprint and low efficiency. It cannot spheroidize high-molecular organic powder materials with low melting point and easy to burn. Plasma is a process in which high-temperature plasma flame is formed by high-voltage discharge. The powder passes through plasma, is melted by high temperature and spheroidized, cooled, shaped and collected. The temperature difference between different parts of the plasma flame is extremely large, which affects the spheroidization effect. In addition, the powder concentration to a certain extent will affect the discharge and easily extinguish the plasma. It has high power, high power consumption, low efficiency and complex electrical control. It cannot spheroidize high-molecular organic powder materials with low melting point and easy to burn. The gas phase method is technically difficult and has poor safety. The powder obtained by the liquid phase method has large intermolecular gaps and low compactness. Summary of the invention

[0004] The object of the present invention is to provide a spheroidizing device for fusible powder materials, the device can spheroidize a wide range of powder materials, and the surface finish of the spheres is higher and more compact when the device is used for powder spheroidization.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A spheroidizing device for fusible powder material, characterized in that: it comprises a melting spheroidizing device and a preheating and heating device, wherein the preheating and heating device is connected to the lower inlet of the melting spheroidizing device;

[0007] The molten spheroidizing device comprises a spheroidizing cylinder, an inner cylinder with upper and lower openings, an anti-turbulence device, a safety bushing, an electromagnetic induction heating coil, a cooling jacket, and a heating device, wherein the inner cylinder is arranged in the spheroidizing cylinder (at a certain distance from the inner wall of the spheroidizing cylinder) to form an annular area; an anti-turbulence device is arranged in the middle and lower part of the spheroidizing cylinder, the upper part of the anti-turbulence device corresponds to the bottom of the annular area, a group of heating devices is arranged on the outer periphery of the cylinder wall at the bottom of the spheroidizing cylinder, a safety bushing and an electromagnetic induction heating coil are arranged on the outer periphery of the cylinder wall at the middle and upper part of the spheroidizing cylinder in sequence, and a cooling jacket is arranged on the outer periphery of the upper cylinder wall of the spheroidizing cylinder;

[0008] The preheating device includes a heating cylinder, a feed hopper, a screw propeller, and a heating device, wherein the heating cylinder is provided with a screw propeller, the outer periphery of the heating cylinder is provided with two groups of heating devices, a feed hopper is provided at one end of the heating cylinder, and a gas replacement device is provided on the feed pipe of the feed hopper.

[0009] Furthermore, the gas replacement device includes an air inlet jacket tube and an air outlet jacket tube fixed on the outer periphery of the feed pipe, and the air inlet jacket tube and the air outlet jacket tube are respectively provided with an air inlet and an air outlet, and an annular cavity is formed between the air inlet jacket tube and the air outlet jacket tube and the feed pipe, and the corresponding feed pipe in the annular cavity is evenly distributed with air inlet micropores and air outlet micropores around it.

[0010] Furthermore, the upper part of the anti-turbulence device is fixed to the outer wall of the lower part of the inner cylinder through a connecting rod, and the lower part of the anti-turbulence device is fixed to the platform of the inner wall of the spheroidizing cylinder.

[0011] Furthermore, the anti-turbulence device includes a trapezoidal cylinder and an inverted conical cylinder, the inverted conical cylinder is fixed to the middle of the trapezoidal cylinder by a connecting rod; the inverted conical cylinder is fixed to the lower part of the inner cylinder by the connecting rod, corresponding to the lower end of the annular area formed between the inner cylinder and the spheroidizing cylinder, and the lower part of the trapezoidal cylinder is fixed to the platform of the inner wall of the spheroidizing cylinder.

[0012] Furthermore, the inner cylinder is fixed to the inner wall of the spheroidizing cylinder through a connecting rod.

[0013] Furthermore, a blade stirrer is provided at the bottom of the spheroidizing cylinder, and the blade stirrer is connected to the motor.

[0014] Furthermore, a safety bushing is provided between the electromagnetic induction heating coil and the spheroidizing cylinder to ensure the safety of the spheroidizing cylinder when the temperature is greater than 600°C.

[0015] The advantages of the present invention are as follows: the device has a small size, a simple structure, is easy to control, and has low energy consumption; the device can spheroidize a wide range of powder materials, which can be organic polymer material powders, such as polytetrafluoroethylene powders, etc., or inorganic non-metallic material powders, such as glass powders, etc. During the floating process, the surface of the spheres after being squeezed and polished by tin liquid has a higher smoothness and is more compact. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a simplified structural diagram of a spheroidizing device for fusible powder materials;

[0017] Figure 2 is a schematic diagram of the structure of a gas displacement device;

[0018] Figure 3 It is a schematic diagram of the structure of the anti-turbulence device. DETAILED DESCRIPTION

[0019] Combination Figure 1 , Figure 2 and Figure 3 , the present invention is further described:

[0020] A spheroidizing device for fusible powder material, comprising a vertical melting spheroidizing device B and a horizontal preheating device A, wherein the preheating device A is vertically connected to the lower side wall of the melting spheroidizing device B;

[0021] The molten spheroidizing device B comprises a spheroidizing cylinder 9, an inner cylinder 10 with upper and lower openings, an anti-turbulence device 7, a safety bushing 12, an electromagnetic induction heating coil 14, a cooling jacket 15, and an electric heater 11, wherein the inner cylinder 10 is fixed to the inner wall of the spheroidizing cylinder 9 (at a certain distance from the inner wall of the spheroidizing cylinder) by a connecting rod 8 to form an annular area X, and the powder is melted and spheroidized in the tin liquid in the annular area X; a group of electric heaters 11 are arranged on the outer periphery of the bottom cylinder wall of the spheroidizing cylinder 9 to heat the bottom tin liquid, and a safety bushing 12 and an electromagnetic induction heating coil 14 are arranged on the outer periphery of the middle and upper cylinder walls of the spheroidizing cylinder 9 in sequence, and the temperature of the tin liquid in the melting section and the spheroidizing section is heated by the electromagnetic induction heating coil 14, and a cooling jacket 15 is arranged on the outer periphery of the upper cylinder wall of the spheroidizing cylinder 9 The jacket 15 is provided with a cooling medium in the cooling jacket; an anti-turbulence device 7 is provided in the middle and lower part of the spheroidizing cylinder 9, and the anti-turbulence device 7 includes a trapezoidal cylinder 7a and an inverted conical cylinder 7b, the inverted conical cylinder 7b is fixed to the middle part of the trapezoidal cylinder 7a by a connecting rod 8, and the inverted conical cylinder 7b is fixed to the outer wall of the lower part of the inner cylinder 10 by the connecting rod 8, and corresponds to the lower part of the annular area X formed between the inner cylinder 10 and the spheroidizing cylinder 9, and the lower part of the trapezoidal cylinder 7a is fixed to the platform on the inner wall of the spheroidizing cylinder 9; a blade stirrer 6 is provided at the bottom of the spheroidizing cylinder 9, and the blade stirrer 6 is connected to the motor 13, and the motor 13 drives the blade stirrer 6 to rotate (the shaft of the blade stirrer is temperature-controlled and cooled), so that the fusible powder is fully mixed with the tin liquid at the bottom;

[0022] The preheating and heating device A comprises a heating cylinder 3, a feed hopper 1, a screw propeller 2, and an electric heater 5, wherein the heating cylinder 3 is provided with a screw propeller 2, and two groups of electric heaters 5 are provided on the periphery of the heating cylinder 3, so as to preheat and heat the fusible powder in the heating cylinder 3 in turn, and one end of the heating cylinder 3 is connected to the feed hopper 1, and a gas replacement device C is provided on the feed pipe of the feed hopper 1 to replace the air in the fusible powder, and the gas replacement device C comprises an air inlet jacket tube C1 and an air outlet jacket tube C3, and the air inlet jacket tube C1 and the air outlet jacket tube C3 are respectively An air inlet and an air outlet are provided. The air inlet jacket C1 and the air outlet jacket C3 are fixed on the lower and upper parts of the feed pipe in sequence, and annular cavities are formed between the feed pipe and the feed pipe, respectively. Air inlet micropores C2 and air outlet micropores C4 are evenly distributed around the corresponding feed pipe in the annular cavity. The reducing gas enters from the air inlet micropores C2 at the bottom and exchanges air with the fusible powder coming from the top of the pipe. A part of the reducing gas enters the heating cylinder 3 along with the fusible powder, and the other part of the reducing gas and air come out from the air outlet micropores C4 at the top of the pipe and the outlet of the feed hopper 1.

[0023] When the device is in use, the device is filled with tin liquid, and soluble powder (glass powder, polytetrafluoroethylene powder, polyamide 66 powder, polyethylene terephthalate powder, etc.) is added from the feed hopper 1, and enters the heating cylinder 3 after ventilation through the gas replacement device (reducing gas), and is gradually preheated (normal temperature to 120°C) and heated (120 to 245°C) by the screw propeller 2, and then enters the bottom of the spheroidizing cylinder 9 to mix with the tin liquid (235 to 350°C), and is stirred and dispersed evenly by the blade stirrer 6. The evenly dispersed fusible powder enters the gap Y formed by the inverted conical cylinder 7b and the spheroidizing cylinder 9 from the lower part of the trapezoidal cylinder 7a due to buoyancy, and enters the annular area X formed between the inner cylinder 10 and the spheroidizing cylinder 9 along the gap. The fusible powder entering the annular area X The powder balls are gradually melted and spheroidized in the tin liquid (the melting and spheroidizing temperatures suitable for the powders are selected from 250 to 2200°C according to the different melting and spheroidizing temperatures of different powders). The tin liquid in the annular area X is heated by the electromagnetic induction heating coil 14. The melted and spheroidized powder balls continue to float to the cooling and solidification section (the cooling and solidification temperatures corresponding to the powder balls are selected from 235 to 2000°C according to the different cooling and solidification temperatures of different powder balls). The tin liquid in the cooling and solidification section descends along the inside of the inner cylinder 10 into the inverted conical cylinder 7b, enters the annular area X along the gap between the inverted conical cylinder 7b and the inner cylinder 10, and is cooled and solidified by the cooling jacket 15 and the cooling medium in the jacket, and accumulates on the tin liquid surface (collecting section) of the upper part of the spheroidizing cylinder 9. When it is full, it overflows by itself or is sucked out by a device.

Claims

1. A spheroidizing device for fusible powder, characterized in that: It comprises a molten spheroidizing device (B) and a preheating and heating device (A), wherein the preheating and heating device (A) is connected to the lower inlet of the molten spheroidizing device (B); The molten spheroidizing device (B) comprises a spheroidizing cylinder (9), an inner cylinder (10) with upper and lower openings, an anti-turbulence device (7), an electromagnetic induction heating coil (14), a cooling jacket (15), and a first electric heater (11), wherein the inner cylinder (10) is arranged in the spheroidizing cylinder (9) to form an annular area (X); an anti-turbulence device (7) is arranged in the middle and lower part of the spheroidizing cylinder (9), the upper part of the anti-turbulence device (7) corresponds to the bottom of the annular area (X), a group of first electric heaters (11) are arranged on the outer periphery of the bottom wall of the spheroidizing cylinder (9), an electromagnetic induction heating coil (14) is arranged on the outer periphery of the middle and upper wall of the spheroidizing cylinder (9), and a cooling jacket (15) is arranged on the outer periphery of the upper wall of the spheroidizing cylinder (9); The preheating device (A) comprises a heating cylinder (3), a feed hopper (1), a screw propeller (2), and a second electric heater (5), wherein the heating cylinder (3) is provided with a screw propeller (2), the outer periphery of the heating cylinder (3) is provided with two groups of second electric heaters (5), the feed hopper (1) is provided at one end of the heating cylinder (3), and a gas replacement device (C) is provided on the feed pipe of the feed hopper (1); The gas replacement device (C) comprises an air inlet jacket pipe (C1) and an air outlet jacket pipe (C3) fixed to the outer periphery of the feed pipe, the air inlet jacket pipe (C1) and the air outlet jacket pipe (C3) are respectively provided with an air inlet and an air outlet, and an annular cavity is formed between the air inlet jacket pipe (C1) and the air outlet jacket pipe (C3) and the feed pipe, and the air inlet micropores (C2) and the air outlet micropores (C4) are uniformly distributed around the corresponding feed pipe in the annular cavity; The anti-turbulence device (7) comprises a trapezoidal cylinder (7a) and an inverted conical cylinder (7b), wherein the inverted conical cylinder (7b) is fixed to the middle of the trapezoidal cylinder (7a) by a connecting rod (8); the inverted conical cylinder (7b) is fixed to the outer wall of the lower part of the inner cylinder (10) by the connecting rod, and is matched with the lower end of the annular area (X) formed between the inner cylinder (10) and the spheroidizing cylinder (9), and the lower part of the trapezoidal cylinder (7a) is fixed to the platform on the inner wall of the spheroidizing cylinder (9).

2. The spheroidizing device for fusible powder according to claim 1, characterized in that: The upper part of the anti-turbulence device (7) is fixed to the outer wall of the lower part of the inner cylinder (10) through a connecting rod, and the lower part of the anti-turbulence device (7) is fixed to the platform of the inner wall of the spheroidizing cylinder (9).

3. The spheroidizing device for fusible powder according to claim 1, characterized in that: The inner cylinder (10) is fixed to the inner wall of the spheroidizing cylinder (9) via a connecting rod.

4. The spheroidizing device for fusible powder according to claim 1, characterized in that: A blade stirrer (6) is provided at the bottom of the spheroidizing cylinder (9), and the blade stirrer (6) is connected to a motor (13).

5. The spheroidizing device for fusible powder according to claim 1, characterized in that: A safety bushing (12) is provided between the electromagnetic induction heating coil (14) and the spheroidizing cylinder (9).

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