JP4190964B2 - Pressurized gas cooling device for heat treatment furnace and operation method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pressurized gas cooling device for a heat treatment furnace capable of reducing the consumption of pressurized gas for cooling and an operation method thereof.
[0002]
[Prior art]
As a heat treatment furnace, particularly a vacuum heat treatment furnace, a two-chamber pressurized gas cooling vacuum furnace is known as disclosed in Non-Patent Document 1, for example. This type of vacuum furnace is provided with a heating chamber for heat-treating the treatment material and a cooling chamber for cooling the heat-treated treatment material, and when the treatment material is transferred from the heating chamber to the cooling chamber for cooling treatment. For example, a cooling pressurized gas is supplied to the cooling chamber so that the cooling chamber is pressurized and cooled, and after the cooling process, the pressurized gas filled in the cooling chamber is evacuated. By discharging it, the cooling chamber is brought into a reduced pressure state.
[0003]
When a dedicated cooling chamber is provided for the cooling process in this way, there is an advantage that the processing material can be rapidly cooled without having to cool the heating chamber once subjected to the heat treatment, and a large cooling rate can be secured. Further, pressurized cooling using a pressurized gas is advantageous for securing a large cooling rate. As the pressurized pressure gas for cooling, in order to prevent the oxidation reaction of the treatment material, a gas whose pressure is increased to about several hundred KPa to several MPa is used.
[0004]
As shown in FIG. 4, the conventional structure of the cooling device including the cooling chamber of the heat treatment furnace is provided adjacent to the heating chamber a, and a pair of cooling chambers c for cooling the processing material b is provided. A fan housing g communicated via a duct d and a fan f provided in the fan housing e, and the fan f that circulates a pressurized pressurized gas for cooling with the cooling chamber c by the fan f; The cooling chamber c is connected to the duct d and provided in a supply system h for supplying a pressurized pressurized gas to the cooling chamber c, and a first discharge pipe m connected to the cooling chamber c. An openable and closable diffusion valve k that discharges the pressurized pressurized gas until atmospheric pressure is reached, and connected to the cooling chamber c via the second exhaust pipe i, and the pressurized pressurized gas for cooling is evacuated to atmospheric pressure. And a vacuum pump j for discharging.
[0005]
The fan device g and the cooling chamber c constitute a circulation circuit that is closed from the outside via the duct d, and during the cooling process, while sequentially supplying the pressurized gas from the supply system h to the cooling chamber c, The pressurized gas is circulated by the fan device g. Further, when the processing material b is taken out from the cooling chamber c, the diffusion valve k is opened, the pressurized gas is discharged until the inside of the cooling chamber c reaches atmospheric pressure, and then the pressurized gas is further increased by the vacuum pump j. The cooling chamber c is opened after being evacuated and discharged under atmospheric pressure.
[0006]
[Non-Patent Document 1]
Japan Heat Treatment Technology Association, “Heat Treatment Technology Handbook”, first edition, Nikkan Kogyo Shimbun, August 30, 2000, p. 776-779
[0007]
[Problems to be solved by the invention]
By the way, in the cooling device of the conventional heat treatment furnace, the cooling chamber c is always in communication with the pair of ducts d and the fan housing e of the fan device g. All the pressurized gas supplied in an amount that can fill the entire space in the duct d and the fan housing e is exhausted after the cooling process, and is consumed in one cooling process. There was a problem that a large amount of pressurized gas was required.
[0008]
The present invention has been devised in view of the above-described conventional problems, and provides a pressurized gas cooling device for a heat treatment furnace capable of reducing the consumption of cooling pressurized gas and an operation method thereof. Objective.
[0009]
[Means for Solving the Problems]
The pressurized gas cooling device of the heat treatment furnace according to the present invention is brought into a pressurized state by supplying a pressurized gas for cooling when the processing material carried from the heating chamber is cooled, and after the cooling processing, A cooling chamber that is decompressed by discharging the pressurized gas for cooling, a fan housing that communicates with the cooling chamber via a pair of ducts, and a fan that is provided in the fan housing. In a pressurized gas cooling apparatus for a heat treatment furnace having a fan device that circulates a pressurized pressurized gas for cooling between the cooling chamber and the cooling chamber, the first duct is configured to open and close each of the pair of ducts. A first on-off valve and a second on-off valve are provided, and the first and second on-off valves are simultaneously opened when the cooling chamber is pressurized and before the cooling chamber is depressurized, Characterized in that simultaneously closed in order to shut off between § emission device.
[0010]
The first and second on-off valves provided in each of the pair of ducts are closed at the same time to shut off the cooling chamber and the fan device, and before the pressurized gas for cooling is discharged to depressurize the cooling chamber. By simultaneously closing these on-off valves, the amount of pressurized gas discharged can be made the amount staying in the cooling chamber side duct from the cooling chamber and the first and second on-off valve positions, Compared to the case where the first and second on-off valves are not provided, the amount of pressurized gas to be discharged can be reduced.
[0011]
Also, by closing the first and second on-off valves at the same time, a considerable amount of additional pressure staying in the pressurized state in the fan device housing and in the duct on the fan device side from the first and second on-off valve positions. When the cooling chamber is pressurized for the next cooling process, the pressurized gas can be supplied to the cooling chamber as it is by simultaneously opening the first and second on-off valves. The next cooling process can be performed, and the amount of new pressurized gas to be supplied from the supply system can also be reduced. Thus, the amount of pressurized gas to be discharged and the amount of pressurized gas to be supplied can be reduced, and the consumption of pressurized gas can be reduced.
[0012]
Further, since the discharge amount of the pressurized gas can be reduced, it is possible to shorten the time for depressurizing the cooling chamber, and the efficiency of the discharge process can be improved.
[0013]
Further, a gas cooler for cooling the pressurized pressurized gas circulated in the duct is provided between the fan device and one of the first on-off valve and the second on-off valve. A gas cooler is provided, and the circulating pressurized pressurized gas can be appropriately cooled and sent to the cooling chamber. The gas cooler is connected to one of the first and second on-off valves and a fan device. Thus, by closing the first and second on-off valves at the same time, the pressurized gas in the gas cooler can also stay on the fan device side. Compared with the case where the second on-off valve is installed on the cooling chamber side, the amount of the pressurized gas discharged, that is, the consumption of the pressurized gas can be reduced.
[0014]
Further, a supply end of a supply system that supplies pressurized gas for cooling is inserted into at least one of the ducts to connect the duct and the supply system, and a gas inlet port of the supply end is provided. The cooling gas is directed in the circulation direction along the duct. By using the gas flow blown from the gas blow-in port of the supply system, the flow of pressurized gas circulating in the duct can be strengthened, and the pressurized gas accumulated in the fan device can be sent out by the fan device smoothly. Thus, the circulation of the pressurized gas can be made steady in a short time, the pressurizing operation time of the cooling chamber can be shortened, and the necessary capacity of the fan device can be reduced.
[0015]
Further, according to the operating method of the pressurized gas cooling apparatus for the heat treatment furnace according to the present invention, when the processing material carried from the heating chamber is cooled, the pressurized pressure gas for cooling is supplied to make the pressurized state. A cooling chamber that is decompressed by discharging the cooling pressurized gas after the cooling process, a fan housing that communicates with the cooling chamber via a pair of ducts, and a fan provided in the fan housing. In the operating method of the pressurized gas cooling device of the heat treatment furnace having a fan device configured to circulate the pressurized gas for cooling between the cooling chamber and the cooling chamber by the fan at the time of the cooling process , provided in each of the pair of ducts The first on-off valve and the second on-off valve are simultaneously opened when the cooling chamber is pressurized, and at the same time to shut off the cooling chamber and the fan device before the cooling chamber is depressurized. Close Characterized in that way the.
[0016]
Before exhausting the pressurized gas for cooling in order to depressurize the cooling chamber, the first and second on-off valves provided in each of the pair of ducts are simultaneously closed to shut off the cooling chamber and the fan device. The amount of pressurized gas to be discharged can be the amount staying in the cooling chamber and the duct on the cooling chamber side from the first and second on-off valve positions, reducing the amount of pressurized gas to be discharged Can do.
[0017]
Also, by closing the first and second on-off valves at the same time, a considerable amount of additional pressure staying in the pressurized state in the fan device housing and in the duct on the fan device side from the first and second on-off valve positions. When the cooling chamber is pressurized for the next cooling process, the pressurized gas can be supplied to the cooling chamber as it is by simultaneously opening the first and second on-off valves. Thus, the next cooling process can be performed, and the amount of new pressurized gas to be supplied from the supply system can be reduced. Thus, the amount of pressurized gas to be discharged and the amount of pressurized gas to be supplied can be reduced, and the consumption of pressurized gas can be reduced.
[0018]
Further, since the discharge amount of the pressurized gas can be reduced, it is possible to shorten the time for depressurizing the cooling chamber, and the efficiency of the discharge process can be improved.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of a pressurized gas cooling apparatus for a heat treatment furnace according to the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, the two-chamber pressurized gas cooling vacuum furnace is exemplified as the heat treatment furnace 1. Of course, the heat treatment furnace 1 may be a cooling heat treatment furnace or the like. The pressurized gas cooling device 2 is mainly provided adjacent to the heating chamber 3, the processing material 4 is carried in from the heating chamber 3, the loaded processing material 4 is cooled, and after the cooling processing, the processing material 4 The cooling chamber 5 having a closed structure, the first duct 6 and the second duct 7 whose one ends are connected to the cooling chamber 5, respectively, and the other end of the first duct 6 at the suction port, The fan device 8 having the other end of the two ducts 7 connected to the discharge port, the first on-off valve 9 and the second on-off valve 10 provided in each of the pair of ducts 6, 7, and the second duct 7 A supply system 11 connected between the on-off valve 10 and the discharge port of the fan device 8 to supply a cooling pressurized gas such as nitrogen gas, hydrogen gas, helium gas, etc., to the cooling chamber 5; Gas cooler provided between the first on-off valve 9 of the duct 6 and the fan device 8 2, it consists of a connected discharge system 13. the cooling chamber 5.
[0020]
In order to supply the pressurized pressurized gas to the cooling chamber 5, the supply system 11 has a reserve tank 14 filled with the pressurized pressurized gas for cooling at one pressure, one end connected to the reserved tank 14, and the other end at the other end. A supply end 15a (see FIG. 2) includes a supply pipe 15 connected to the second duct 7, and an adjustment valve 16 provided in the supply pipe 15 to adjust the supply amount of pressurized gas. . The cooling chamber 5 is brought into a pressurized state by the pressurized gas supplied from the supply system 11 when the processing material 4 carried in from the heating chamber 3 is cooled.
[0021]
The fan device 8 includes a fan housing 17 communicated with the inside of the cooling chamber 5 through a pair of ducts 6 and 7 and a fan 18 that is rotationally driven and cools the treatment material 4. During processing, the pressurized gas is drawn from the cooling chamber 5 into the fan housing 17 through the first duct 6 by the operation of the fan 18, and the drawn pressurized gas is drawn from the fan housing 17 through the second duct 7 into the cooling chamber 5. Circulate the cooling gas back to The fan device 8 and the cooling chamber 5 constitute a circulation circuit closed from the outside through a pair of ducts 6 and 7.
[0022]
The gas cooler 12 cools the pressurized gas in the cooling chamber 5 heated by cooling the treatment material 4 when it is drawn into the fan device 8 and flows through the first duct 6. ing. The discharge system 13 is provided in the first discharge pipe 24 connected to the cooling chamber 5 in order to discharge the pressurized gas for cooling and the like, and is opened until the inside of the cooling chamber 5 reaches atmospheric pressure. An openable / closable diffusion valve 23 for discharging the pressurized gas, a vacuum pump 19 for evacuating the pressurized gas to atmospheric pressure, and one end connected to the vacuum pump 19 and the other end connected to the cooling chamber 5. 2, and an exhaust opening / closing valve 21 that is provided in the middle of the second discharge pipe 20 and opens and closes the second discharge pipe 20 in accordance with the start / stop of the vacuum pump 19. Then, after the cooling process, that is, when the processing material 4 is carried out of the cooling chamber 5, the cooling chamber 5 is decompressed by discharging the pressurized gas by the discharge system 13.
[0023]
In particular, the first and second on-off valves 9 and 10 provided in the first and second ducts 6 and 7 so as to be freely opened and closed simultaneously close the first and second ducts 6 and 7 before the decompression operation. Thus, the fan device 8, the gas cooler 12, and the supply system 11 are cut off from the cooling chamber 5 connected to the discharge system 13.
[0024]
In the present embodiment, as shown in FIG. 2, the supply pipe 15 of the supply system 11 is inserted into the second duct 7 so that the supply end 15a including the gas blowing port 22 is inserted. Connected to the second duct 7, the gas inlet 22 is arranged along the length direction of the second duct 7 and in the direction Q of circulation of the pressurized gas flowing from the fan device 8 toward the cooling chamber 5. Is done.
[0025]
Next, an operation method of the pressurized gas cooling device 2 of the heat treatment furnace 1 according to the present embodiment having the above-described configuration will be described. FIG. 3 shows the change in the pressure in the cooling chamber with the passage of time for cooling the treatment material 4. In the standby state in which the treatment material 4 is carried from the heating chamber 3 to the cooling chamber 5, the inside of the cooling chamber 5 is set to an almost atmospheric pressure state (indicated by a in the drawing).
[0026]
At the start of the cooling process, the cooling chamber 5 is sealed, and then the first and second on-off valves 9 and 10 are simultaneously opened and the regulating valve 16 is opened, whereby the supply pipe 15 and the second duct 7 are opened from the reserve tank 14. By supplying a new pressurized gas for cooling to the cooling chamber 5 through the cooling chamber, the pressure in the cooling chamber is increased to be in a pressurized state (indicated by a in the figure). At this time, the exhaust opening / closing valve 21 and the diffusion valve 23 of the exhaust system 13 are of course closed. At the same time, the operation of the fan device 8 is started, and the pressurized gas supplied into the cooling chamber 5 is circulated. At this time, if the pressurized gas from the previous cooling process stays on the fan device 8 side, the previous addition from the fan device 8 side by simultaneous opening of the first and second on-off valves 9 and 10. The pressurized gas flows into the cooling chamber 5.
[0027]
When the pressure in the cooling chamber reaches a predetermined pressurized state, the supply of pressurized gas from the reserve tank 14 is stopped by closing the regulating valve 16 while continuing the circulation of the pressurized gas by the operation of the fan device 8. Thus, while the pressurized gas is cooled by the gas cooler 12, the treatment material 4 is subjected to a cooling treatment under the steady circulation (indicated by “u” in the figure).
[0028]
When the cooling process is completed, the inside of the cooling chamber 5 is depressurized. Before the pressure reducing operation, the fan device 8 is stopped and the first and second on-off valves 9 and 10 are closed at the same time, whereby the fan device 8 and the gas cooler 12 and also these on-off valves 9 and 10 are closed. Further, the pressurized gas is contained in the ducts 6 and 7 on the fan device 8 side so as to be retained. If the first and second on-off valves 9 and 10 are closed at the same time, the diffusion valve 23 of the discharge system 13 is opened, the pressurized gas is discharged from the cooling chamber 5, and the pressure in the cooling chamber is temporarily set to atmospheric pressure. (Represented by D in the figure). Thereafter, the diffusion valve 23 is closed while the exhaust on-off valve 21 is opened. At the same time, the vacuum pump 19 is activated to evacuate the pressurized gas from the cooling chamber 5 to the atmospheric pressure, and to the atmosphere such as nitrogen gas. The pressurized gas that dislikes the emission of the gas is almost completely discharged from the cooling chamber 5 (indicated by o in the figure).
[0029]
Next, the cooling chamber 5 is filled with air and returned to atmospheric pressure (indicated by “K” in the figure). At this point, the processing material 4 is unloaded from the cooling chamber 5 (indicated by “K” in the figure). Thereafter, the air that has flowed into the cooling chamber 5 and is now filled is evacuated by the vacuum pump 19 and is almost completely discharged (indicated in FIG. 1).
[0030]
Finally, in preparation for the next cooling process, the pressurized gas is filled in the cooling chamber 5 to about the atmospheric pressure (indicated by a mark in the figure). At this time, if the first and second on-off valves 9 and 10 are opened at the same time, the pressurized gas retained on the fan device 8 side by closing the on-off valves 9 and 10 is sent into the cooling chamber 5. Can do. Moreover, you may make it supply a new pressurized gas from the supply system 11 as needed. In this way, it is possible to shift to a standby state for the next cooling process (indicated by a in the figure).
[0031]
As described above, in the pressurized gas cooling device 2 and the operating method of the heat treatment furnace 1 according to the present embodiment, the first and second on-off valves provided in the first and second ducts 6 and 7, respectively. 9 and 10 are closed at the same time so that the cooling chamber 5 and the fan device 8 can be shut off. Therefore, before the cooling gas is discharged to reduce the pressure in the cooling chamber 5, the on-off valves 9 and 10 are simultaneously opened. If closed, the amount of the pressurized gas discharged can be made the amount staying in the cooling chamber 5 and the ducts 6 and 7 on the cooling chamber 5 side from the positions of the on-off valves 9 and 10. , 10 can be reduced as compared with the case of not providing 10.
[0032]
Further, by closing these on-off valves 9 and 10 at the same time, the air in the housing 17 and the gas cooler 12 of the fan device 8 and the ducts 6 and 7 on the fan device 8 side from the positions of the on-off valves 9 and 10 can be obtained. A considerable amount of pressurized gas staying in the pressurized state can be supplied to the cooling chamber 5 as it is by opening the on-off valves 9 and 10 at the time of the next cooling process. Thus, the next cooling process can be performed, and the amount of new pressurized gas to be supplied from the supply system 11 can also be reduced.
[0033]
Thus, the amount of pressurized gas to be discharged and the amount of pressurized gas to be supplied can be reduced, and the consumption of pressurized gas can be reduced.
[0034]
Further, since the discharge amount of the pressurized gas can be reduced, the decompression operation time of the cooling chamber 5 can also be shortened, and the efficiency of the discharge process (indicated by D, E, and K in the figure) can be improved.
[0035]
In addition, since the gas cooler 12 for cooling the cooling pressurized gas circulating in the first duct 6 is provided between the fan device 8 and the first on-off valve 9, the circulating cooling pressurized gas is appropriately set. It can be cooled and fed into the cooling chamber 5. Further, by closing the on-off valves 9 and 10 at the same time, the pressurized gas in the gas cooler 12 can also stay on the fan device 8 side, and the gas cooler 12 is closer to the cooling chamber 5 than the on-off valves 9 and 10 are. Compared with the case where it installs in, the amount of pressurized gas discharged | emitted, ie, the consumption of pressurized gas, can further be reduced.
[0036]
Further, the supply end 15a of the supply system 11 for supplying the pressurized pressurized gas for cooling is inserted into the second duct 7 to connect the second duct 7 and the supply system 11, and the gas at the supply end 15a. Since the blow-in port 22 is arranged along the second duct 7 in the circulation direction Q of the pressurized gas for cooling, the flow of the pressurized gas to be circulated is utilized using the gas flow blown from the gas blow-in port 22. It is possible to increase the pressure, the smoothing of the pressurized gas retained by the fan device 8 by the fan device 8 can be facilitated, and the circulation of the pressurized gas can be made steady in a short time. The operation time can be shortened and the necessary capacity of the fan device 8 can be reduced.
[0037]
In the above embodiment, the gas cooler 12 is provided between the fan device 8 and the first on-off valve 9, but between the fan device 8 and the second on-off valve 10 or in the cooling chamber 5. You may make it provide.
[0038]
【The invention's effect】
In short, in the pressurized gas cooling apparatus for a heat treatment furnace and the operating method thereof according to the present invention, the first duct provided in each of the pair of ducts before discharging the cooling pressurized gas to decompress the cooling chamber. The second on-off valve is closed at the same time so as to shut off the cooling chamber and the fan device, and the amount of pressurized gas discharged is changed from the cooling chamber and the first and second on-off valve positions to the cooling chamber side. The amount of pressurized gas to be discharged can be reduced, and the first and second on-off valves can be closed at the same time to close the fan housing and the first and first When the cooling chamber is pressurized for the next cooling process, a considerable amount of pressurized gas staying in a considerably pressurized state from the on-off valve position in the duct on the fan device side is first and second. By opening the on-off valve at the same time, it is directly supplied to the cooling chamber And be Rukoto, which can be performed next cooling process using pressurized gas of the novel to be supplied from the supply system can be reduced. In this way, the amount of pressurized gas to be discharged and the amount of pressurized gas to be supplied can be reduced, and the consumption of cooling pressurized gas can be reduced.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a preferred embodiment of a pressurized gas cooling apparatus for a heat treatment furnace according to the present invention.
FIG. 2 is an enlarged view of part A in FIG.
FIG. 3 is a diagram for explaining the change in the pressure in the cooling chamber, showing a preferred embodiment of the operating method of the pressurized gas cooling apparatus for the heat treatment furnace according to the present invention.
FIG. 4 is a circuit diagram showing a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Heat processing furnace 2 Pressurized gas cooling device 3 Heating chamber 4 Processing material 5 Cooling chamber 6 1st duct 7 2nd duct 8 Fan apparatus 9 1st on-off valve 10 2nd on-off valve 11 Supply system 12 Gas cooler 15a Supply end 17 Fan housing 18 Fan 22 Gas inlet Q Circulation direction of pressurized gas for cooling

Claims (4)

When the processing material carried in from the heating chamber is subjected to a cooling process, a pressurized state is obtained by supplying the cooling pressurized gas, and after the cooling process, the cooled pressurized gas is discharged to reduce the pressure. A cooling chamber, a fan housing communicated with the cooling chamber via a pair of ducts, and a fan provided in the fan housing, and for cooling between the cooling chamber and the cooling chamber by the fan during cooling processing In a pressurized gas cooling device for a heat treatment furnace having a fan device for circulating a pressurized gas , each of the pair of ducts is provided with a first on-off valve and a second on-off valve for opening and closing them.
The first and second on-off valves are simultaneously opened when the cooling chamber is pressurized, and are simultaneously closed to shut off the cooling chamber and the fan device before the cooling chamber is depressurized. pressurized gas cooler of the heat treatment furnace, characterized in that it is. 2. A gas cooler for cooling the pressurized pressurized gas circulated in the duct is provided between the fan device and one of the first on-off valve and the second on-off valve. A pressurized gas cooling device for a heat treatment furnace as described in 1. above.   At least one of the ducts is inserted with a supply end of a supply system for supplying a pressurized pressurized gas to connect the duct and the supply system, and the gas blow-in port at the supply end is connected to the above-described duct. 3. The pressurized gas cooling device for a heat treatment furnace according to claim 1, wherein the pressurized gas cooling device is directed in a circulating direction of the cooling pressurized gas along the duct. When the processing material carried in from the heating chamber is subjected to a cooling process, a pressurized state is obtained by supplying the cooling pressurized gas, and after the cooling process, the cooled pressurized gas is discharged to reduce the pressure. A cooling chamber, a fan housing communicated with the cooling chamber via a pair of ducts, and a fan provided in the fan housing, and for cooling between the cooling chamber and the cooling chamber by the fan during cooling processing In a method of operating a pressurized gas cooling device for a heat treatment furnace having a fan device for circulating pressurized gas , the cooling chamber is pressurized with the first on-off valve and the second on-off valve provided in each of the pair of ducts. while open at the same time that, the operation of the cooling chamber and the fan device heat treatment furnace pressurized gas cooling device being characterized in that to close simultaneously in order to cut off between the before said cooling chamber is depressurized Law.

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