JPH0622335U - Powder production equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the accuracy and durability of the nozzle hole of the molten metal nozzle and prevent the nozzle hole from being blocked due to leakage of the molten metal. [Structure] The heat-resistant thin tube 41 is inserted into the nozzle hole of the melt nozzle 27, and a gap is formed between the inner circumference of the nozzle hole 27d of the melt nozzle 27 and the outer circumference of the upper end of the heat-resistant thin tube 41, so that the leaked melt can be kept in this gap. House inside.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a powder production apparatus for producing metal powder by a gas atomizing method, and particularly to improvement of a molten metal nozzle for injecting molten metal melted in a melting crucible.

[0002]

[Prior art]

 As a device for producing metal powder, a powder producing device using a gas atomizing method has been conventionally known. This equipment stores a metal sample in a melting crucible, melts it by induction heating, and injects it into a lower injection chamber from a melt nozzle provided at the bottom of the melting crucible. At this time, an inert gas is jetted at high speed from a gas jet nozzle provided at the lower end of the molten metal nozzle, and the molten metal jetted from the molten metal nozzle is made into metal powder by a gas atomizing method.

[0003]

[Problems to be solved by the device]

 Conventionally, the above-mentioned molten metal nozzle is formed of a heat-resistant material such as alumina into a substantially columnar shape, and has a small hole penetrating in the axial direction at the center. For this reason, it is difficult to accurately form the pores, and it has been impossible to inject the molten metal at an appropriate flow rate. Also, the inlet side of the melt nozzle was closed with a stopper except during injection, but it could not be completely sealed, and the melt could leak into the melt nozzle and block the pores.

The present invention has been made in view of the above points, and it is possible to accurately form a pore penetrating the center of the molten metal nozzle and prevent clogging of the molten metal nozzle due to leakage of molten metal. It is an object to provide a powder manufacturing apparatus.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the powder manufacturing apparatus according to claim 1 melts a metal sample in a melting crucible by induction heating, and uses a gas atomizing method through a molten metal nozzle provided at the bottom of the melting crucible. In the powder production apparatus for producing metal powder by spraying, a heat-resistant thin tube penetrating the center of the molten metal nozzle is provided.

Further, the powder producing apparatus according to claim 2 is characterized in that the heat-resistant thin tube protrudes from the inner peripheral end surface of the upper portion of the melt nozzle, and a gap is formed between the outer periphery of the heat-resistant thin tube and the inner circumference of the melt nozzle.

[0007]

[Action]

 According to the powder producing apparatus of claim 1, the heat-resistant thin tube penetrating the center of the molten metal nozzle is formed of a material having excellent workability and high mechanical strength, thereby improving the accuracy of the inner diameter of the molten metal. The flow rate can be optimized and the durability can be improved.

Further, according to the powder producing apparatus of the second aspect, when the molten metal in the melting crucible leaks, the molten metal accumulates in a gap between the outer periphery of the heat-resistant thin tube and the inner periphery of the molten metal nozzle, and the molten metal nose Does not block

[0009]

【Example】

 An embodiment of the powder production apparatus of the present invention will be described below with reference to the drawings.

1 to 4 show the configuration of an embodiment of the present invention. FIG. 3 shows a schematic structure of the powder production apparatus according to this embodiment. An upper injection chamber 2 is fixed on a gantry 1, and a lower injection chamber 3 is provided under the upper injection chamber 2 in close contact with each other. Has been. The lower injection chamber 3 is supported by a carriage 4, and a recovery port 5 for recovering the produced powder is detachably attached to the lower end of the lower injection chamber 3. The upper injection chamber 2 is provided with a front view window 6, a hot water receiving mechanism 7, and an internal lighting device 8, and a melting part 9 is attached to the upper part.

A gas jet nozzle 10 described below is provided between the melting section 9 and the upper injection chamber 2, and a gas release valve 11 is connected to the upper injection chamber 2. A melting chamber 12 is provided above the melting section 9, and the inside of the melting chamber 12 is evacuated by a vacuum exhaust device 13. Further, a sample addition rod 14 for adding a metal sample and a shelving rod 15 are attached to the melting chamber 12. Reference numeral 16 in FIG. 3 is a surge tank, and reference numeral 17 is a compound meter.

FIG. 4 shows a detailed structure of the melting portion 9. A coil 22 for induction heating is wound around the outer cylinder 21 of the melting section 9, and a melting crucible 24 is placed on a bottom plate 23 inside the outer cylinder 21 via a carbon sheet 25. . The bottom plate 23 of the outer cylinder 21 is mounted on the upper injection chamber 2 via a water-cooled copper plate 26, and the bottom of the melting crucible 24, the bottom plate 23, and the upper wall of the upper injection chamber 2 have concentric holes. Portions 24a, 23a and 2a are formed. The molten metal nozzle 27 is attached to the holes 24a and 23a, and the gas jet nozzle 10 is attached to the hole 2a.

An inverted conical recess 27a of about 90 degrees is formed on the upper end surface of the melt nozzle 27, and the melt nozzle 27 is driven by a stopper 28 that is driven up and down via a rod 19 by a cylinder 18 shown in FIG. Is opened and closed. The lower end of the melt nozzle 27 is fitted in the center hole of the gas jet nozzle 10, and a large number of injection holes (not shown) are concentrically formed on the outer periphery of the center hole of the gas jet nozzle 10. Then, an inert gas such as Ar supplied through the pipe 29 passes through the jet nozzle 10 and is jetted from the jet holes. Further, a gate valve 30 for opening and closing the central hole is provided on the lower surface of the central hole of the gas jet nozzle 10 via a packing 31.

In the powder manufacturing apparatus configured as described above, the melting crucible 24 containing the metal sample is placed in the melting section 9 that is evacuated by the vacuum evacuation device 13, and the melting nozzle 27 Is closed by a stopper 28. When a high frequency voltage is applied to the coil 22, the metal sample in the melting crucible 24 is induction-heated and melted. Next, the molten metal is pressurized in the melting chamber 12 so as to be discharged, and at the same time the gate valve 30 is opened, the molten metal stopper 28 is raised by driving the air cylinder 31, and the initial molten metal discharge timer is used to set the initial molten metal discharge and the gas jet. An inert gas is supplied from the nozzle 10 and is injected from the injection hole to the outer periphery of the lower end of the molten metal nozzle 27. As a result, the molten metal becomes a powder by the gas atomizing action and is recovered in the recovery pot 5 through the injection chambers 2 and 3. The inert gas injected into the upper injection chamber 2 is released to the outside through the gas release valve 11.

FIG. 1 shows the structure of the molten metal nozzle 27, which is a feature of this embodiment. The molten metal nozzle 27 is made of a heat-resistant material such as aluminum, and is formed into a substantially cylindrical shape.The enlarged diameter portion 27b is provided at the upper end, the reduced diameter portion 27c is provided at the lower end, and the nozzle hole 27d penetrating in the axial direction is provided at the center. It has been done. Further, as described above, the inverted cone-shaped recess 27a of about 90 degrees is formed on the upper end surface of the molten metal nozzle 27. Further, a heat-resistant thin tube 41 made of a material having excellent workability and high mechanical strength is closely inserted into the nozzle hole 27d.

According to this embodiment, since the heat-resistant thin tube is inserted into the nozzle hole 27d of the molten metal nozzle 27, the accuracy of the nozzle inner diameter can be improved and the molten metal can be smoothly injected at an appropriate flow rate. Further, the durability of the molten metal nozzle 27 can be improved, and the clogging of the nozzle hole 27d due to clogging of the molten metal can be prevented.

FIG. 2 shows the configuration of another embodiment of the present invention. In the present embodiment, the diameter of the upper portion of the nozzle hole 27d is expanded, and the upper end of the heat-resistant thin tube 41 is projected into the expanded diameter portion 27e.

In this embodiment, since a gap is formed between the inner circumference of the enlarged diameter portion 27e of the nozzle hole 27d and the outer circumference of the upper end of the heat-resistant thin tube 41, the stopper 28 shown in FIG. 4 completely seals the nozzle hole 27d. If the molten metal leaks into the molten metal nozzle 27, the molten metal accumulates in the gap, so that the nozzle hole 27d is not blocked.

[0019]

[Effect of device]

 As described above, according to the powder manufacturing apparatus of claim 1, since the heat-resistant thin tube is inserted into the nozzle hole of the molten metal nozzle, the accuracy and durability of the nozzle hole can be improved, and the nozzle caused by the water clogging can be improved. It is possible to prevent blockage of the holes.

Further, according to the powder producing apparatus of the second aspect, since the gap is formed between the inner circumference of the nozzle hole of the molten metal nozzle and the outer circumference of the heat-resistant thin tube, the molten metal is not melted when the stopper seals the molten metal nozzle. Even if it leaks, it does not accumulate in the gap and block the nozzle hole.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the structure of a molten metal nozzle according to an embodiment of a powder manufacturing apparatus of the present invention.

FIG. 2 is a vertical cross-sectional view showing the structure of a molten metal nozzle according to another embodiment of the present invention.

FIG. 3 is a front view showing a schematic configuration of a powder production apparatus according to an embodiment of the present invention.

FIG. 4 is a vertical cross-sectional view showing the configuration of the melting section of FIG.

[Explanation of symbols]

 24 Melting crucible 27 Molten metal nozzle 41 Heat-resistant thin tube

Claims (2)

[Scope of utility model registration request] 1. A powder production apparatus for producing a metal powder by melting a metal sample in a melting crucible by induction heating and jetting it by a gas atomizing method through a molten metal nozzle provided at the bottom of the melting crucible, A powder production apparatus, characterized in that a heat-resistant thin tube that penetrates through the center of the melt nozzle is provided. 2. The powder manufacturing apparatus according to claim 1, wherein the heat-resistant thin tube projects from the upper inner peripheral end surface of the melt nozzle, and a gap is formed between the outer periphery of the heat-resistant thin tube and the inner circumference of the melt nozzle.