JP2018169081A - Cooling device for metal powder - Google Patents

Abstract

To provide a cooling device for a metal powder capable of executing cooling processing on the metal powder in a short time and efficiently.SOLUTION: A cooling device 1 for a metal powder comprises: stream piping 12 coupled to a lower end of a throw-in tank 11 into which a heated metal powder is thrown, for streaming the metal powder; a storage tank 13 for storing the metal powder that is streamed through the stream piping 12; a transport tank 14 that is provided at a downstream side of the storage tank 13; and transport piping 15 coupled to a lower end of the transport tank 14, for transporting the metal powder from the transport tank 14 to a processing device of a next process. In the stream piping 12, a cooling gas intake port 12A for taking in a cooling gas is provided at a coupling position with the throw-in tank 11. The metal powder is streamed while being cooled within the stream piping 12 by the cooling gas that is taken in from the cooling gas intake port 12A.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a metal powder cooling device, and more specifically, efficiently cools a heated metal powder in a short time after heat treatment or drying treatment is performed under high temperature conditions. The present invention relates to an apparatus for cooling metal powder.

  The metal powder can be obtained, for example, by precipitating and forming metal particles from a solution containing a reducing agent, or by pulverizing a metal compound obtained by crystallization from a solution into particles with a pulverizer or the like. The metal powder thus obtained is subjected to a heat treatment under a high temperature condition, or an operation of removing the moisture adhering to the metal powder by washing the metal powder and drying at a high temperature. . Thereafter, the metal powder (heated powder) heated by the treatment under the high temperature condition is cooled to a predetermined temperature or lower prior to being transferred to the next step in which, for example, processing is performed.

  In general, the metal powder is cooled because the thermal conductivity between the metal powders is poor, so the powder is stirred and cooled in the cooling device, or the cooling device is vibrated. It is performed by a method such as cooling by exchanging heat with the can body while flowing the powder charged in the apparatus.

  Specifically, the cooling of the powder in the cooling device includes indirect cooling in which heat exchange is performed with a refrigerant flowing in a cooling jacket provided in the device, and powder and heat while blowing cold air directly into the cooling device. There is a direct cooling method to perform replacement.

  However, in these methods, the heat conduction of the powder is very poor, the cooling time is inevitably long, and an efficient operation cannot be performed. Further, when the cooling time of the powder becomes long, there is a problem that the amount of foreign matter mixed in the powder due to wear of the cooling device and the powder increases. Furthermore, when the time for cooling the powder becomes long, it is necessary to increase the size of the cooling equipment in order to increase the amount of processing and perform efficient operation.

  On the other hand, in order to speed up the powder cooling process, for example, when trying to increase the stirring ability in the apparatus, a device that minimizes wear by spraying a high hardness material on the can body and stirring blades. Although it is necessary to apply, these measures greatly increase the equipment cost. In addition, since it is impossible to completely eliminate the wear between the equipment and powder, it is necessary to perform maintenance on the equipment regularly. It becomes expensive and the maintenance itself becomes difficult.

  In Patent Document 1, as a cement cooling system, a pumping facility that pneumatically feeds cement from a transport vehicle to a storage tank facility and a facility that cools air below a predetermined temperature are provided, and cooling is performed during transportation. A method of cooling using air is disclosed. However, the technique described in Patent Document 1 is a technique related to cooling of cement and cannot be easily applied to cooling of metal powder.

Japanese Patent Laying-Open No. 2015-136861

Powder Technology Overview 2014-2015, Japan Powder Technology Association, p88-105

  This invention is proposed in view of such a situation, and it aims at providing the cooling device of the metal powder which can perform the cooling process with respect to metal powder in a short time and efficiently.

  As a result of intensive studies, the present inventor has caused the heated metal powder to flow through the flow pipe that has taken in the cooling gas, and thereby heat generated by contact with the cooling gas in the flow pipe. As a result of the exchange, the inventors have found that the metal powder can be efficiently cooled in a short time while flowing the metal powder, and have completed the present invention.

  (1) The first invention of the present invention is connected to a lower end portion of a charging tank into which heated metal powder is charged, and includes a feeding pipe for feeding the metal powder, and the feeding pipe. A storage tank for storing the metal powder flowed through, a transfer tank provided on the downstream side of the storage tank, and a lower end of the transfer tank. A transfer pipe for transferring the metal powder to the processing apparatus, and the flow pipe is provided with a cooling gas inlet for taking in the cooling gas at a connection point with the charging tank. The metal powder is a metal powder cooling device that is fed while being cooled in the feed pipe by the cooling gas taken in from the cooling gas inlet.

  (2) A second invention of the present invention is the metal powder according to the first invention, comprising a blower that is provided above the storage tank and sucks the cooling gas to flow the metal powder. It is a cooling device.

  (3) In a third aspect of the present invention, in the first or second aspect, the storage tank is configured to measure the temperature of the metal powder stored in the storage tank via the flow pipe. This is a metal powder cooling device provided with a temperature sensor.

  (4) According to a fourth aspect of the present invention, in the third aspect, the transfer pipe is provided with a switching valve for switching a transfer destination of the metal powder transferred from the transfer tank, and the temperature When the temperature of the metal powder measured by the sensor exceeds a predetermined temperature, the metal powder is returned to the storage tank via a circulation pipe connected to the transfer pipe at the point of the switching valve. It is a cooling device for metal powder.

  (5) According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the transfer pipe has a cooling gas intake port that takes in the cooling gas at a connection point with the transfer tank. A metal powder cooling device that is provided and that cools the metal powder passing through the transfer pipe.

  ADVANTAGE OF THE INVENTION According to this invention, the cooling device of the metal powder which can perform the cooling process with respect to metal powder in a short time and can be provided efficiently.

It is a schematic diagram which shows the structural example of the cooling device of metal powder.

  Hereinafter, a specific embodiment of the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. In addition, this invention is not limited to the following embodiment, A various change is possible in the range which does not change the summary of this invention.

  FIG. 1 is a schematic diagram showing a configuration of a metal powder cooling device (hereinafter also simply referred to as “cooling device”) according to the present embodiment. The metal powder cooling device 1 includes an input tank 11 into which heated metal powder (heated powder) is charged, and an inflow pipe 12 that is connected to the lower end of the input tank 11 to flow the heated powder. The storage tank 13 for storing the heated powder flown through the flow pipe 12, the transfer tank 14 provided on the downstream side of the storage tank 13, and the lower end of the transfer tank 14 are connected. And a transfer pipe 15 for transferring the metal powder from the transfer tank 14 to a processing apparatus in which the next process is performed.

  The cooling device 1 is provided with a cooling gas intake port 12A for taking in the cooling gas at the connection point with the input tank 11 in the flow pipe 12, and the heated powder is fed from the cooling gas intake port 12A. It is characterized by being fed while being cooled in the flow pipe 12 by the taken-in cooling gas.

  In addition, the cooling device 1 is provided with a control unit 30 that controls the transfer destination of the metal powder. The control unit 30 transfers the metal powder to the processing apparatus in which the next process is performed based on the measured temperature of the metal powder that is flowed while being cooled in the flow pipe 12, or is again a storage tank. 13 is controlled to circulate and transfer.

  According to the cooling device 1 having such a configuration, when the heated powder passes through the feed pipe, it is sent while being cooled by the cooling gas, so that the cooling process can be efficiently performed in a short time. it can. In addition, since there is no need to perform a cooling process by separately providing a cooling device that is equipped with additional equipment such as a conventional stirring blade and vibration device and that cools while applying stirring processing and vibration, foreign matter is mixed into the metal powder. There is no fear and equipment costs can be effectively reduced. Moreover, the metal powder cooled by the control part 30 based on a predetermined reference | standard can be reliably transferred to the next process.

  Specifically, according to the cooling device 1 according to the present embodiment, a predetermined amount of metal powder can be cooled at about 4 ° C. to 5 ° C./min. In a conventional cooling device, for example, a cooling device that cools with stirring, when the cooling treatment is performed on the same amount of metal powder, the cooling rate is about 1 ° C. to 2 ° C./min.

  Hereinafter, each configuration of the cooling device 1 will be described more specifically.

[Input tank]
The charging tank 11 is a tank that temporarily stores the heated metal powder. The input tank 11 is not particularly limited, and a known storage tank can be used. Moreover, the valve | bulb 11a which can adjust the insertion of the heating powder to the inflow piping 12 can be provided in the lower end part of the injection tank 11, ie, a connection location with the inflow piping 12 mentioned later.

  Generally, a metal powder is heated by a high temperature condition after being manufactured by a wet method or the like, or is subjected to a drying process after washing, so that the powder is heated to a high temperature. Such high-temperature heated powder is cooled to a temperature of about 50 ° C. or less, for example, before being subjected to a predetermined treatment in the next step. In the cooling device 1 according to the present embodiment, the produced heated powder is temporarily stored in the charging tank 11 and is then sent to the next process while being cooled via a feed pipe 12 described later.

[Flow pipe]
The inflow pipe 12 is a pipe for inflowing heated powder. One end of the inflow pipe 12 is connected to the lower end of the input tank 11 and the other end is connected to the storage tank 13, and the heated powder is supplied between the input tank 11 and the storage tank 13. An arrow F <b> 1 in FIG. 1 indicates the flow direction of the heated powder through the flow pipe 12.

  Here, the flow pipe 12 is provided with a cooling gas inlet 12 </ b> A that takes in the cooling gas at a connection point with the charging tank 11. For example, a cooling gas such as air cooled to a predetermined temperature is supplied to the cooling gas inlet 12A, and the cooling gas is taken into the flow pipe 12 through the cooling gas inlet 12A. Thus, in the cooling device 1, the cooling gas is taken into the inflow pipe 12 for flowing the heated powder, and heat exchange is performed when the heated powder comes into contact with the cooling gas. It is possible to carry out the cooling process efficiently in a short time.

An example of the cooling gas taken into the inflow pipe 12 is cooled air. In this manner, the heated powder can be fed while being efficiently cooled by air-flowing with the cooled air. The cooling gas is not limited to air, and may be, for example, an inert gas such as nitrogen (N ₂ ) gas or argon gas to prevent oxidation, or air from which moisture at a low dew point has been removed. It may be determined appropriately depending on the relationship with the metal powder to be fed.

  Further, the cooling gas can be taken into the flow pipe 12 at a predetermined wind speed. By allowing the cooling gas having a predetermined wind speed to be taken in, the heated powder can be efficiently cooled and the inside of the inflow pipe 12 can be smoothly fed.

  Further, as will be described in detail later, a blower 17 is provided above the storage tank 13, and the cooling gas taken into the flow pipe 12 by the blower 17 is sucked so that the heated powder is flowed. You can also

[Storage tank]
The storage tank 13 is connected to a flow pipe 12, and is flowed through the flow pipe 12 to store and store the heated powder. As described above, in the flow pipe 12, the heated powder is flowed while being cooled by the cooling gas, so the heated powder charged via the flow pipe 12 was cooled to a predetermined degree. It is a metal powder in a state.

  The storage tank 13 is not particularly limited, and a known storage tank can be used. The storage tank 13 can be provided with a cooling member such as a cooling jacket on the outer periphery of the tank, for example. Thereby, the metal powder charged and stored in the storage tank 13 from the inflow pipe 12 can be cooled.

  The storage tank 13 is provided with a bag filter unit 16 at an upper portion thereof, and collects dust so that the manufactured metal powder is not discharged to the outside through the blower 17 and returns it to the tank. In addition, a blower 17 is connected to the bag filter unit 16, and since the inside of the storage tank 13 becomes negative pressure due to suction by the blower 17, the flow of heated powder fed through the feed pipe 12 is reduced. Send. Further, as will be described later, the metal powder circulated and returned from the transfer pipe 15 can be efficiently circulated and transferred.

  The bag filter unit 16 is not particularly limited, and a heat-resistant filter such as a known dust collector can be used. Also, the blower 17 is not particularly limited as long as particles can be pumped, and a known one such as a centrifugal blower or an axial flow blower can be used.

  The storage tank 13 is provided with a temperature sensor 13T to measure the temperature of the stored metal powder. The temperature sensor 13 </ b> T measures the temperature of the metal powder that is flowed while being cooled through the flow pipe 12 and is stored in the storage tank 13, and transmits the measured temperature information of the metal powder to the control unit 30. . As a result, the control unit 30 can determine whether or not the metal powder stored in the storage tank 13 has been cooled to an arbitrarily set target temperature.

  The storage tank 13 is connected to the transfer tank 14 on the downstream side, and the metal powder stored in the storage tank 13 is then transferred to the transfer tank. A rotary valve 18 can be provided at a connection location between the storage tank 13 and the transfer tank 14. Thereby, the quantity of the metal powder transferred from the storage tank 13 to the transfer tank 14 can be appropriately adjusted according to the pipe length, the flow rate, and the cooled air quantity.

[Transfer tank]
The transfer tank 14 is provided on the downstream side of the storage tank 13 as described above, and temporarily stores the metal powder charged from the storage tank 13. A transfer pipe 15 to be described later is connected to the transfer tank 14, and basically, metal powder transferred to the processing apparatus in which the next process is performed through the transfer pipe 15 is temporarily stored. .

  As the transfer tank 14, a known storage tank can be used.

[Transfer piping]
The transfer pipe 15 is a pipe for transferring metal powder from the transfer tank 14 to a processing apparatus in which the next process is performed. One end of the transfer pipe 15 is connected to the lower end of the transfer tank 14, and the other end is connected to a processing apparatus for the next process, and transfers the metal powder from the transfer tank 14 to a predetermined processing apparatus. An arrow F2 in FIG. 1 indicates the transfer direction of the metal powder through the transfer pipe 15.

  Here, in the transfer pipe 15, a cooling gas intake port 15 </ b> A for taking in the cooling gas can be provided at a connection point with the transfer tank 14. Similarly to the cooling gas inlet 12A provided in the flow pipe 12, the cooling gas inlet 15A provided in the transfer pipe 15 is supplied with a cooling gas such as cooled air, and the cooling gas intake. Cooling gas is taken into the transfer pipe 15 through the inlet 15A. In this way, by taking the cooling gas into the transfer pipe 15 as well, the metal powder transferred to the next step can be transferred while being cooled. In addition, the transfer speed of the metal powder is increased, and retention and the like can be prevented. At this time, the same configuration as that of the storage tank 13, the bag filter unit 16, and the blower 17 described above may be provided in the transfer to the next process via the transfer pipe 15.

  In addition, as shown in FIG. 1, the supply source of the cooling gas taken in from the cooling gas inlet 12A of the flow pipe 12 and the cooling gas inlet 15A of the transfer pipe 15 can be made common. The same cooling gas can be taken in.

  A circulation pipe 19 is connected to the transfer pipe 15 so as to branch at a predetermined location. A switching valve 20 is provided at a connection point (point) between the transfer pipe 15 and the circulation pipe 19 to switch the transfer destination of the metal powder transferred from the transfer tank 14.

  The circulation pipe 19 connected to the transfer pipe 15 is a pipe for circulating and transferring the metal powder whose transfer destination is switched by the switching valve 20. The other end of the circulation pipe 19 is connected to the inflow pipe 12 before being connected to the storage tank 13, and a circulation switching valve 21 is provided at the connection point between the circulation pipe 19 and the inflow pipe 12. ing. The circulation switching valve 21 switches the metal powder (charging source) charged into the storage tank 13, and the metal powder fed from the charging tank 11 through the feeding pipe 12. Or the metal powder circulated and transferred through the circulation pipe 19 is switched. In this way, the metal powder is circulated and transferred through the circulation pipe 19 and returned to the flow pipe 12 so that the metal powder can be cooled again by the cooling gas. An arrow F3 in FIG. 1 indicates the transfer direction of the metal powder through the circulation pipe 19.

  Specifically, when the metal powder supplied from the transfer tank 14 is transferred, the metal powder is cooled to a target temperature or less based on whether or not the metal powder is a target temperature that is arbitrarily set or not. The metal powder thus obtained is transferred as it is to the processing apparatus of the next process through the transfer pipe 15. On the other hand, since the metal powder in a state exceeding the target temperature is a powder that has not been sufficiently cooled, the metal powder passes through the circulation pipe 19 via the transfer pipe 15 based on the transfer switching by the switching valve 20. Circulated and transferred. As described above, since the other end of the circulation pipe 19 is connected to the flow pipe 12, the metal powder is circulated through the circulation pipe 19 and then cooled again by the cooling gas.

[Control unit]
The control unit 30 controls the transfer destination of the metal powder. The control unit 30 is electrically connected to the temperature sensor 13T provided in the storage tank 13 and the switching valve 20 provided in the middle of the transfer pipe 15 (connection point with the circulation pipe 19), respectively. Based on the measured temperature of the metal powder measured in the storage tank 13, it is controlled whether the metal powder is transferred to a processing apparatus in which the next process is performed or is circulated again to the storage tank 13. .

  Specifically, when the temperature of the metal powder that has been fed in the storage tank 13 while being cooled in the feeding pipe 12 is measured by the temperature sensor 13T, the control unit 30 uses the temperature sensor 13T to measure the temperature. Receive the information. The control unit 30 determines whether or not the received measurement temperature of the metal powder is equal to or lower than a target temperature (set target temperature) that is arbitrarily set in advance. For example, when the set target temperature is 50 ° C., the control unit 30 determines whether the measurement temperature of the metal powder is 50 ° C. or less or exceeds 50 ° C., and if the measurement temperature is 50 ° C. or less, It is determined that the metal powder is sufficiently cooled, and if it exceeds 50 ° C., it is determined that the metal powder is not yet sufficiently cooled.

  And the control part 30 controls the transfer destination of the metal powder via the transfer piping 15 based on the judgment of the cooling degree of the metal powder based on the measured temperature. That is, when the control unit 30 determines that the measured temperature of the metal powder is equal to or lower than the set target temperature and the metal powder is sufficiently cooled, the control unit 30 does not change the state via the transfer pipe 15 (without switching the switching valve 20). The metal powder is transferred to a processing apparatus in which the next process is performed. On the other hand, if it is determined that the measured temperature of the metal powder exceeds the set target temperature and the metal powder is not sufficiently cooled, the switching valve 20 is switched and transferred to the circulation pipe 19 via the transfer pipe 15. . As described above, the circulation pipe 19 is connected to the feed pipe 12 through which the cooling gas flows, and circulates and transfers the metal powder that is not sufficiently cooled.

  In this way, the control unit 30 accurately controls the transfer destination of the metal powder based on the measurement temperature of the metal powder. Thereby, the cooling device 1 can reliably and efficiently perform the cooling process on the metal powder, and can effectively prevent the metal powder still having high temperature heat from being transferred to the next process. it can.

  In addition to the control based on the measurement temperature of the metal powder by the temperature sensor 13T as described above, the control unit 30 controls the metal powder to intentionally circulate a plurality of times (for example, five times). Also good. For example, when the metal powder supplied from the transfer tank 14 is transferred through the transfer pipe 15, the control unit 30 intentionally switches the switching valve 20 to circulate and transfer it to the circulation pipe 19. Repeat 5 times. Then, after the circulation of 5 times is completed, the metal powder stored in the storage tank 13 is measured by the temperature sensor 13T, and is circulated again based on the measured temperature, or the next step through the transfer pipe 15 Control whether to transfer to the other processing equipment.

  As described above, according to the metal powder cooling device 1 according to the present embodiment, when the heated metal powder passes through the flow pipe 12, it is flowed while being cooled by the cooling gas. Therefore, the cooling process can be performed efficiently in a short time. Further, since there is no need to separately provide a cooling device for cooling while stirring as in the prior art, there is no possibility of foreign matters mixed in the metal powder, and the equipment cost can be effectively suppressed.

  Further, by providing the control unit 30 to circulate the metal powder based on a predetermined standard, the cooled metal powder can be reliably transferred to the next process.

  In the present embodiment, the mode in which the cooling gas is taken in from the cooling gas inlet 12A of the flow pipe 12 and the cooling gas inlet 15A of the transfer pipe 15 is shown, but the present invention is not limited to this. For example, a similar cooling gas intake port may be provided at a position in the middle of the flow pipe 12 or the transfer pipe 15, and the cooling gas may be taken in from the position in the middle.

DESCRIPTION OF SYMBOLS 1 Cooling device 11 Input tank 12 Flow piping 12A Cooling gas intake 13 Storage tank 13T Temperature sensor 14 Transfer tank 15 Transfer piping 15A Cooling gas intake 16 Bag filter unit 17 Blower 18 Rotary valve 19 Circulation piping 20 Switching Valve 21 Circulation switching valve 30 Control unit

Claims (5)

Connected to the lower end of the charging tank into which the heated metal powder is charged, and an inflow pipe for flowing the metal powder;
A storage tank for storing the metal powder fed through the flow pipe;
A transfer tank provided downstream of the storage tank;
A transfer pipe connected to the lower end of the transfer tank, for transferring the metal powder from the transfer tank to a processing apparatus for the next process;
With
The inflow pipe is provided with a cooling gas intake port for taking in the cooling gas at a connection point with the charging tank,
The metal powder cooling device is a metal powder cooling device which is fed while being cooled in the flow piping by the cooling gas taken in from the cooling gas inlet. The metal powder cooling device according to claim 1, further comprising a blower that is provided above the storage tank and sucks the cooling gas to flow the metal powder. 3. The metal powder cooling according to claim 1, wherein the storage tank is provided with a temperature sensor that measures the temperature of the metal powder stored in the storage tank via the inflow pipe. apparatus. The transfer pipe is provided with a switching valve for switching a transfer destination of the metal powder transferred from the transfer tank,
When the temperature of the metal powder measured by the temperature sensor exceeds a predetermined temperature, the metal powder is returned to the storage tank via a circulation pipe connected to the transfer pipe at the point of the switching valve. The metal powder cooling device according to claim 3. 5. The transfer pipe is provided with a cooling gas intake port for taking in a cooling gas at a connection position with the transfer tank, and the metal powder passing through the transfer pipe is cooled. The metal powder cooling device according to any one of the above.

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