JP3050087B2 - Charge extraction equipment for continuous heat treatment furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention suppresses the flow of atmospheric gas in a furnace from the furnace inlet and outlet when a long heat-treated material such as a metal tube is continuously charged or discharged into a continuous heat-treating furnace. The present invention relates to a charging and extracting apparatus for a continuous heat treatment furnace.

[0002]

2. Description of the Related Art In metalworking, improvement of structure and mechanical properties by heat treatment is an indispensable process.
Since the material to be heat-treated is exposed to a high temperature of several hundred degrees Celsius, there is a problem of oxidation. For this reason, when the surface properties of the material to be heat treated are important, an atmosphere adjusting gas such as an inert gas, a nitrogen gas, or a dehydration combustion gas is supplied into the furnace so that air is not brought into contact with the material to be heat treated. An atmosphere heat treatment furnace is used.

[0003] obtained in the continuous heat treatment furnace for processing among long thermally treated material of this atmosphere heat treatment furnace continuously, always charged part of the opening to the elongated thermally treated material of the furnace, forced to perform discharge Absent. For this reason, in a continuous heat treatment furnace, the pressure of the atmosphere gas in the furnace is always higher than the atmospheric pressure so that the atmosphere does not enter the furnace.
High positive pressure is maintained. The positive pressure of the in-furnace atmosphere gas may be within a range that can reliably prevent air from entering the normal furnace is adjusted to e.g. 1mmAq on more than. However, when the long material to be heat-treated is a tubular body, it may be expected to increase the gas pressure in the furnace to expel the air in the tube in order to prevent air trapped in the tube from being brought into the furnace. .

In such a case, the following method has conventionally been adopted to increase the gas pressure in the furnace. (1). A method of simply increasing the supply amount of the atmospheric gas in accordance with the required furnace gas pressure. (2) As shown in FIG. 3 , a method in which gas curtain devices 45 and 44 for delivering and sucking the same gas as the atmosphere gas in the furnace are installed at entrances 43 and 42 of the continuous heat treatment furnace 41. (3) .As shown in FIG. 4 , a method of attaching heat-resistant curtains 55 and 54 to the entrances and exits 53 and 52 of the continuous heat treatment furnace 51 so that the long heat-treated material 56 can freely enter and exit.
Usually, asbestos-like products or strips of titanium plates are alternately hung. The above-mentioned conventional methods alone are not sufficiently effective, and are often applied in combination.

[0005] In the operation of the continuous heat treatment furnace, a long material to be heat-treated is charged from the furnace inlet, heat-treated inside the furnace, and then discharged from the furnace outlet. In the furnace of the continuous heat treatment furnace, an adjustment gas is constantly fed by an atmosphere gas supply blower to fill the inside of the furnace, and thereafter, an adjustment gas having the same amount as the fed amount is discharged from the furnace inlet and outlet. At the furnace entrance and exit, there is an entrance side curtain and an exit side curtain,
In addition to increasing the furnace pressure by providing resistance to the gas flow, it prevents the atmosphere from entering the furnace due to disturbance such as strong wind.

As another method, an inlet space and an outlet space through which an atmospheric gas corresponding to a conditioning gas injected into the furnace is discharged from the furnace inlet and outlet are formed. The outlet space causes a pressure loss in the discharged atmospheric gas, and the atmospheric gas in the inlet space and the outlet space is reduced to such a degree that the opening of the furnace inlet and the opening of the outlet do not become a negative pressure with respect to the atmospheric pressure. There has been proposed a furnace (Japanese Patent Publication No. 7-808) provided with a gas circulating means for sucking air and discharging the inside of the furnace.

Further, in the continuous heat treatment furnace, it is necessary to make the furnace length as long as possible in order to increase the heat treatment capacity. Therefore, the conventional continuous heat treatment furnace has a disadvantage that the furnace length is long and the space becomes very large.

[0008]

According to the method (1) for increasing the supply amount of the atmosphere gas, the supply amount of the atmosphere gas needs to be increased in proportion to a half power of the furnace gas pressure. Not only the atmospheric gas, but also a device for generating or supplying the atmospheric gas needs to be increased in size, resulting in a significant increase in cost. Also, the formation of the gas curtain at the furnace entrance and exit in the above (2) requires a large amount of atmosphere gas for the gas curtain, and the cost increases to a degree that is not much different from the method of increasing the supply amount of the atmosphere gas.

Furthermore, the attachment to the furnace entrance of curtains (3), since the entry and exit of structure to long to be heat-treated can be performed freely is a prerequisite, blocking effect is not sufficient, the in-furnace gas pressure It is not very useful to increase the gas supply amount, and the gas supply amount is slightly smaller than the method of increasing the supply amount of the atmospheric gas. Furthermore, the continuous heat treatment furnace disclosed in Japanese Patent Publication No. 7-808 is very difficult to control, and is not very effective as a result of the high initial investment amount for practical use. In some cases, oxygen is easily sucked in, and when circulated in the furnace, there is a fear that the long heat-treated material may be oxidized. Further, in order to increase the furnace capacity of the continuous heat treatment furnace, it is necessary to extend the furnace length, but in some cases, it is not possible to increase the capacity due to space issues.

An object of the present invention is to solve the above-mentioned disadvantages of the prior art, to increase the gas pressure in the furnace without increasing the supply amount of atmospheric gas, and to minimize the air entering the furnace. It is an object of the present invention to provide a charging and extracting apparatus for a continuous heat treatment furnace which can obtain the same effect as that obtained by extending the furnace length while maintaining the current space.

[0011]

Means for Solving the Problems The present inventors have intensively studied and studied to achieve the above object. As a result, as shown in FIG. 5, conventionally, the length in the furnace inlet 62 parts of a continuous heat treatment furnace 61
A furnace interior charging device 64 for charging the shank heat-treated material 63 into the furnace is provided.
Reduced by 65. Although not shown,
The furnace outlet by noting is provided with the outside of the furnace discharge device for discharging from the furnace the long heat treatment material. The entire inlet and outlet of the furnace are covered with the entire furnace interior and the outside of the furnace, and the long heat-treated material is charged.
A carry-in port and a carry-out port for the long heat-treated material in a direction perpendicular to the direction or the discharge direction, and a cover having a lifting door at the carry-in port and the carry-out port are provided. a loading device for <br/> carried from a direction perpendicular to the loading direction of the elongated thermally treated material of the furnace width of the carry-out for unloading in a direction perpendicular to the discharge direction of the long heat treatment material from the outside of the furnace discharge device on by providing the device, Sonyuchu the long thermally treated material on the furnace interior inserting apparatus in a furnace to close the elevator door of the long object to be heat-treated material entrance, of the furnace width of the elongated thermally treated material It is prepared on the loading device, and when the loading of the long heat-treated material into the furnace is completed, the elevating door is opened and the long heat-treated material on the loading device is removed.
After loading onto the furnace interior charging device from a direction orthogonal to the charging direction , the elevating door is closed and the long heat treatment material on the furnace interior loading device is started to be loaded into the furnace. and, also, the discharge side of the elongated heat-treated on the outside of the furnace discharge device by opening the lifting door
By unloading the unloading apparatus in a direction perpendicular to the direction, it is possible to suppress to a minimum the outflow of atmospheric gas, the length
To investigate the ability to preheated in cover length thermally treated material and reached to the present invention.

That is, the first aspect of the present invention is directed to
After the long heat-treated material conveyed to the furnace is continuously charged from the furnace inlet, the adjusting gas atmosphere is formed while sending the adjusting gas into the furnace, and the long heat-treated material is heated and heat-treated in the furnace. In the charging / extracting device for a continuous heat treatment furnace that is continuously discharged from the furnace outlet, the entire furnace interior charging device and the entire furnace discharging device provided at the furnace inlet and outlet are covered, and a long heat treatment material is charged. Long heat in the direction perpendicular to the discharge direction or the discharge direction
Has a carry-in port and carry-out port of the processing member, the cover having a lifting door in the entrance and unloading port is provided, perpendicular to the loading direction of the elongated thermally treated material of the furnace width of the furnace interior inserting apparatus on Do
A loading device for loading the direction, a charging extractor continuous heat treatment furnace, characterized in that a carrying-out device for unloading in a direction perpendicular to the discharge direction of the long heat treatment material from the outside of the furnace discharge device.

The invention according to the second aspect of the present invention is the charging / extracting apparatus for a continuous heat treatment furnace according to claim 1, wherein an elevating door is provided at a furnace entrance of the continuous heat treatment furnace.

[0014]

According to the present invention, a device for charging and extracting a long heat-treated material is provided.
Furnace inlet and covers the whole entire furnace interior inserting apparatus and outside the furnace discharge device to an outlet portion, and also charging direction of the long object to be heat-treated material
Is the entrance and exit of the long heat-treated material in the direction perpendicular to the discharge direction.
Has a pre-carry-out port, by providing the cover with a lifting door in the entrance and unloading port, the furnace interior inserting apparatus on the furnace width of except for carrying the elongated thermally treated material, entrance of The lifting door can be closed. Also, except for unloading the long heat-treated material for the furnace width from the discharge device, the lifting door at the loading port can be closed, so the outflow of atmospheric gas flows into the furnace interior entrance device where the lifting door is opened. and when carrying elongated thermally treated material of the furnace width of, limited from the outside of the furnace discharge device on the furnace width of the long heat-treated at the time of unloading, it is possible to minimize the outflow of atmospheric gas.

The charging extractor elongated thermally treated material of this invention, the elongated thermally treated material of the furnace width of the furnace interior inserting apparatus on instrumentation
By providing a carry-in device for carrying in from a direction perpendicular to the incoming direction and a carry-out device for carrying out the long heat treatment material from above the out-of-furnace discharge device in a direction perpendicular to the discharge direction , during charging the furnace interior inserting apparatus on the long object heat-treated in a furnace, the loading device can prepare the long thermally treated material of the furnace width of on, on the furnace interior inserting apparatus long to be thermally member When the charging into the furnace is completed, the elevating door at the entrance of the cover is opened, and the long heat-treated material corresponding to the furnace width on the loading device is perpendicular to the loading direction on the loading device.
By carrying in from the direction in which the heat treatment is performed, a long material to be heat-treated for the furnace width can be carried into the furnace interior loading device in a very short time.
In addition, the long heat-treated material on the out-of-furnace discharge device opens and closes the elevating opening / closing door at the outlet of the cover, and the unloading device has
The long heat-treated material is carried out at once in a direction perpendicular to the discharge direction . Therefore, the opening time of the lifting door is extremely short, and the outflow of the atmospheric gas can be suppressed to a minimum.

Further, in the charging / extracting apparatus for a continuous heat treatment furnace according to the present invention, the inside of a cover for covering the entire furnace interior charging apparatus and the entire furnace exhausting apparatus at the furnace entrance and exit is provided with a furnace in which a lifting door is opened. Except when loading the long heat-treated material for the furnace width into the interior loading device and when unloading the long heat-treated material for the furnace width from the out-of-furnace discharge device, since it is almost sealed by the lifting door,
Since the temperature is kept close to the atmosphere temperature in the furnace and the long heat-treated material is preheated, the combustion efficiency of the furnace can be increased. In addition, the carry-in and carry-out ports provided on the cover for covering the entire furnace interior entrance apparatus and the whole furnace outside discharge apparatus at the furnace entrance and exit sections of the present invention are provided at right angles to the long heat treatment material charging direction of the cover. You. With this , the long heat-treated material from the furnace interior charging device and the furnace outside discharging device and
Carrying the long heat-treated, the shortening and continuous heat treatment furnace overall length of the discharge time can remain current.

Further, according to the present invention, the elevating opening / closing doors are provided at the furnace entrance and the furnace exit of the continuous heat treatment furnace, so that the charging of the long heat-treated material on the furnace interior charging device into the furnace is completed. in, after closing the elevator door of the furnace inlet, opens the elevator door of the loading opening of the cover, loading direction on a charging device the long thermally treated material of the furnace width of the carry-in device
After loading and unloading the doors of the loading / unloading door, open the doors of the loading / unloading equipment and open the doors of the loading / unloading device.
The long material to be heat-treated is charged into the furnace. Further, after the outside of the furnace discharge device on the long heat-treated was closed elevator door of the outlet when discharged, it opens the elevator door of the unloading opening of the cover, long on the outside of the furnace discharge device Direct heat treatment material to discharge direction
After carrying out by the carry-out device in the intersecting direction , closing the lift opening / closing door at the discharge opening, and opening the lift opening / closing door at the discharge opening, the outflow of the atmospheric gas can be almost completely suppressed.

As a continuous heat treatment furnace to which the charging and extracting apparatus of the present invention is installed, there is a roller hearth type in which a material to be heat treated is fed on a rotating roller. As the loading / unloading device for the long material to be heat-treated in the charging / extracting device of the present invention, a skid conveyor is disposed between the roller conveyors in the case of a roller hearth type continuous heat treatment furnace so that the skid conveyor can be moved up and down, and the skid conveyor is raised in the horizontal direction After loading the long heat-treated material from, the skid conveyor is lowered, the long heat-treated material is placed on the roller conveyor, the skid conveyor is raised, and the long heat-treated material is unloaded laterally.
The skid conveyor may be lowered.

[0019]

Embodiment 1 Hereinafter, a charging and extracting apparatus for a continuous heat treatment furnace according to the present invention will be described in detail with reference to FIGS. 1 and 3 showing an embodiment. Figure
1 is a perspective view of a charging device portion for carrying a long heat-treated material from a lateral direction onto a furnace interior charging device at a furnace inlet portion of a continuous heat treatment furnace,
FIG. 2 is a block diagram of a control system for charging a long heat-treated material to a continuous heat treatment furnace. In FIG. 1, 1 is a continuous heat treatment furnace, 2 is a gas supply blower for supplying an atmospheric gas into the continuous heat treatment furnace 1, and 3 is a furnace inlet of the continuous heat treatment furnace 1 which is always open. 4 comprises a roller conveyor provided outside the furnace entrance 3
Furnace interior inserting apparatus of the long thermally treated material 5, 6 covers the whole furnace interior inserting apparatus 4, and a cover having a loading opening 7 on one side of the loading direction perpendicular to the direction of the long object to be heat-treated material 5, 8 is a loading device consisting of an elevating skid conveyor for loading a long material 5 for the furnace width onto the furnace interior loading device 4; 9 is a line for placing the long material 5 for the furnace width on the loading device 8 Conveyor.

Reference numeral 10 denotes a cylinder that seals the entrance 7 of the cover 6.
An elevating door that opens and closes with 11, and an elevating door 12 that opens and closes with a cylinder 13 that seals the furnace entrance 3 of the continuous heat treatment furnace 1. Sonyuchu the long thermally treated material 5 on the furnace interior inserting apparatus 4 in the furnace, elevating door 12 is open to rise, lifting the door 10 is closed is lowered, long The outflow of the atmospheric gas during the charging of the material to be heat-treated 5 into the furnace is limited to the inside of the cover 6. Then, as shown in FIG.
When the long heat-treated material 5 is completely loaded into the furnace, the cylinder 13 is operated and the elevating door 12 is lowered, and after the furnace inlet 3 is sealed, the cylinder 11 is operated to operate the elevating door. 10 rises, and the entrance 7 is opened. Thereafter, the carry-in device 8 is moved up and the length corresponding to the furnace width previously arranged by the conveyor 9 is reached.
After the heat treatment material 5 is carried from the entrance 7 to the furnace interior loading device 4, it is lowered and the long heat treatment material 5 is placed on the furnace interior loading device 4.
Is mounted.

When the long material 5 to be heat-treated is placed on the furnace interior charging device 4, the cylinder 11 is actuated and the elevating door 10 is lowered, as shown in FIG. After that, the cylinder 13 is operated, the lift door 12 is raised, and the furnace entrance 3 is opened. Next, the furnace interior charging device 4 operates to start charging the long heat-treated material 5 into the furnace. In this case, between the preceding long <br/> be thermally member 5 and the trailing long thermally treated material 5, since the space is vacant, by increasing the rotational speed of the roller conveyor of the furnace interior inserting apparatus 4 Fast Forward 5 trailing long thermally treated material,
It is configured to eliminate the space with the preceding long heat treatment target material 5. Although FIG. 1 above is the furnace inlet 3 side of the continuous heat treatment furnace 1, it is not shown, but the same equipment is also provided on the furnace outlet side of the continuous heat treatment furnace 1 except that no elevating door is provided at the furnace outlet. When the long heat-treated material is discharged onto the out-of-furnace discharge device, the elevating opening / closing door of the cover is opened, the long heat-treated material is carried out from the carry-out device by the carry-out device, and the cover is raised / closed. The door is configured to close.

With the above-described configuration, the atmosphere inside the continuous heat treatment furnace 1 is supplied with a constant amount Q ₁₁
Atmospheric gas is supplied and fills the inside of the continuous heat treatment furnace 1, but the long heat-treated material 5 is
Only time T ₁ that passes through the time fully sealed furnace inlet 3 and outlet is obtained. T ₁ = Long material to be heat-treated 5 (L ₁ ) / Long material to be heat-treated in the furnace 5 Loading speed (V ₁ ) By this sealing time T ₁ , the supply amount of the atmosphere gas in the furnace is Will be reduced. The time T ₂ the elevator door 10 is open, the outer diameter of the elongated thermally treated material 5, always is constant regardless of the length or the like, the longer the length of the long to be thermally member 5 This device has a great effect of reducing the amount of atmospheric gas used in the furnace. Furthermore, when the elevator door 10 is open, the furnace door 3 is closed by closing the elevator door 12 to further reduce the amount of atmosphere gas used in the furnace.

Furthermore, in the present invention, the long heat treatment target material 5 on the furnace interior charging device 4 has a structure in which the entirety is always accommodated in the furnace entrance 3 side cover 6 when charged into the furnace. ,
The long heat treatment target material 5 is preheated by receiving the heat of the atmospheric gas accumulated in the cover 6 from the time of being loaded into the cover 6. Due to this preheating effect, the long heat treatment furnace 1
If the heating capacity when heating the long heat-treated material 5 is reduced, and if the energy for heating is reduced or the same heating energy as the conventional one is used, the heat treatment amount of the long heat-treated material 5 can be increased. it can. Such heat treatment amount increased, there is only means for extension of the furnace body in the conventional, although a limit to the cost was limited in space manner, as shown in FIG. 1, the horizontal direction 5 long the heat treatment material The same effect as extending the conventional furnace length by carrying in and out from
It can be obtained while maintaining the current furnace length.

Example 2 Conventionally, a fuel gas consumption of 500 Nm ³ / Hr and an atmospheric gas supply of 500
In a continuous heat treatment furnace with a furnace width of 1.8 m and a furnace length of 76 m with a furnace gas pressure of 1 mmAq at Nm ³ / Hr, a long heat-treated material with an outer diameter of 100 mm, a wall thickness of 10 mm, and a length of 5.5 m, When charging at a feed rate of 3.3 m / min and performing heat treatment at 980 ° C., the elevating door at the furnace entrance of the charging and extracting apparatus of Example 1 was always open, and the furnace interior of a long heat-treated material was used. Except when loading into the inlet device and when unloading the long heat-treated material from the out-of-furnace discharge device, the elevating door provided on the cover is closed, the gas pressure in the furnace is maintained at 1 mmAq, the wall thickness is 10 mm, and the length is 10 mm. 5.5
m long material to be heat-treated at a feed rate of 3.3 m / min.
After heat treatment at ℃, supply of atmospheric gas 400Nm ³ / H
The gas pressure in the furnace could be maintained at 1 mmAq by r, and the amount of atmospheric gas used could be reduced by about 20%. In addition, when the elevating door at the furnace entrance of the charging and extracting apparatus of Example 1 was closed and sealed when the long heat-treated material was loaded onto the charging apparatus, the atmosphere gas supply amount was 350 Nm ³ / Hr The gas pressure in the furnace could be maintained at 1 mmAq, and the amount of atmospheric gas used could be reduced by about 30%.

In this case, the preheating effect of the long heat-treated material is as follows: a fuel gas consumption of 500 Nm ³ / Hr, an atmosphere gas supply of 500 Nm ³ / Hr, a furnace gas pressure of 1 mmAq, a furnace width of 1.8 m, and a furnace length of
76m continuous heat treatment furnace, outer diameter 100mm, wall thickness 10mm, length 5.5m
The long heat-treated material is charged at a feed rate of 3.3 m / min, and 980
Upon heat treatment is performed ° C., while lifting closing door of the furnace inlet of charging extractor of the first embodiment which is open at all times, and held in the furnace gas pressure 1MmAq, wall thickness 10 mm, length of length 5.5m long When the material to be heat-treated was charged at a feed rate of 3.3 m / min and heat-treated at 980 ° C., the fuel consumption was 460 Nm ³ / Hr, a reduction of about 8%. This means that the heat treatment capacity of the long heat-treated material can be improved by about 8% if the amount of fuel used is not changed. When the long heat-treated material was lifted and closed at the entrance of the furnace into the furnace interior loading device, the fuel consumption was further reduced to about 10%, 450 Nm ³ / Hr.

[0026]

As described above, the carry-in / extraction device for a continuous heat treatment furnace according to the present invention can minimize the outflow of the atmospheric gas in the furnace, reduce the cost of the atmospheric gas, and provide a device for generating or supplying the atmospheric gas. Can be downsized. Further, it is possible to improve the quality of the long heat-treated material and to improve the furnace processing capacity in the existing space.

[Brief description of the drawings]

FIG. 1 is a perspective view of a charging device portion for loading a material to be heat-treated from a lateral direction onto a furnace interior charging device at a furnace inlet of a continuous heat treatment furnace.

FIG. 2 is a block diagram of a control system for charging a material to be heat-treated into a continuous heat treatment furnace.

FIG. 3 is a schematic vertical sectional view of a conventional continuous heat treatment furnace provided with a curtain for preventing the outflow of atmospheric gas from a furnace inlet / outlet.

FIG. 4 is a schematic vertical sectional view of a conventional continuous heat treatment furnace provided with a gas curtain for preventing outflow of atmospheric gas from a furnace inlet / outlet.

FIG. 5 is a perspective view showing a furnace interior charging unit of a conventional continuous heat treatment furnace.

[Explanation of symbols]

1, 41, 51, 61 Continuous heat treatment furnace 2 Gas supply blower 3, 42, 52, 62 Furnace inlet 4, 64 Furnace interior loading device 5, 56, 63 Material to be heat treated 6 Cover 7 Loading port 8 Loading device 9 Conveyor 10, 1 2 elevator door 11,1 3 cylinder 43, 53 oven outlet 54,55,65 curtain 44,45 gas curtain device

──────────────────────────────────────────────────の Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C21D 1/00 112 C21D 1/74 C21D 9/00 101-102 C21D 9/08 F27B 9/00-9 / 40 F27D 7/06

Claims (2)

(57) [Claims] [Claim 1] was charged with elongated thermally treated material conveyed longitudinally continuously from the furnace inlet, the conditioning gas atmosphere and without being forced in the conditioning gas inside the furnace, long the in the furnace In a charging and extracting apparatus for a continuous heat treatment furnace that continuously discharges the heat-treated material from the furnace outlet after heat-treating the heat-treated material, covers the entire furnace interior charging apparatus and the entire outside furnace discharge apparatus provided at the furnace inlet and outlet, and Loading direction or discharging direction of long heat-treated material
Has a carry-in port and carry-out port of the direction orthogonal to the direction elongated thermally treated material,該搬inlet and outlet port a cover having a lifting door, a long furnace width of the furnace interior inserting apparatus on A loading device for loading the material to be heat-treated from a direction perpendicular to the loading direction, and a long heat-treating material from the discharge device outside the furnace perpendicular to the discharge direction.
A charging / extracting apparatus for a continuous heat treatment furnace, comprising a carrying-out device for carrying out in a direction in which the material is carried out. 2. The charging / extracting apparatus for a continuous heat treatment furnace according to claim 1, wherein a lift opening / closing door is provided at a furnace entrance of the continuous heat treatment furnace.