JPS6260443B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an energy-saving roller hearth type continuous furnace that can efficiently heat-treat metals.

For example, a continuous furnace used to preheat another heated object using the heat released when cooling one heated object is manufactured by Tokko Sho.
45-10610 (heat treatment equipment), in such conventional continuous furnaces, the atmosphere inside the furnace can freely flow in the direction of the furnace length, which has an adverse effect on the efficiency of heat exchange. It was hot.

This invention has been made in view of the above, and consists of constructing a furnace body that is U-shaped in plan, and installing conveyor rollers for moving objects to be heated inside the furnace body to form parallel outward and return paths. The bending part of the U-shaped furnace body is equipped with a direction changing device for moving the object to be heated from the forward path side to the return path side, and the parallel in-furnace atmosphere is created at the corresponding part of the parallel forward path side and return path side. A heat exchange chamber is formed by providing a communication duct for exchanging heat, and each heat exchange chamber is provided with a door that can be opened and closed to prevent the atmosphere inside the furnace from flowing in the direction of the furnace length. This is an energy type roller hearth type continuous furnace.

An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a furnace body 1 is constructed in a U-shape in plan with an adiabatic furnace wall, and conveyor rollers 2, 2...... are laid inside the furnace body 1, and heat objects 3, 3 are installed.
A parallel outward path 4 and return path 5 are formed to move the ...... in the direction of the arrow. Each conveyance roller 2, 2...
sprockets 6, 6...... on one end protruding outside the furnace.
are provided, and the sprockets 6, 6...
The endless chains wound around the conveyor rollers 2, 2, .
...... is moved in the direction of the arrow shown. Reference numeral 7 designates a charging table which also includes a group of conveying rollers, and 8 designates an extraction table. A direction change device 9 for moving the object to be heated 3 from the forward path 4 side to the backward path 5 side is provided at the bent portion of the U-shaped furnace body 1 . This direction changing device will be further explained in detail with reference to FIGS. 2 and 5. 10, 10 is higher than the height level of the conveyance rollers 2, 2, etc. so as to bridge from the outward path 4 side to the return path 5 side. The wheel rails 11, 11, which are placed horizontally at a somewhat higher position, are moved from the gap between the conveying rollers 2, 2, . a movable wheel rail configured to be able to protrude up to the same height level as 10;
is the cylinder 1 installed vertically at the bottom of the return path 5 side.
Movable wheel rails 15, 15, . Lifting frames 17, 17, which can protrude higher than the wheel rails 10, 10 from the gap between the conveying rollers 2, 2, by the operation of cylinders 16, 16, which are also vertically provided at the bottom, are the same. An elevating frame is shown which can protrude higher than the wheel rails 10, 10 from the gap between the conveying rollers 2, 2, . A small chamber 2 in which a parallel frame 19 is housed is provided on one side wall of the bent portion of the U-shaped furnace body 1.
0 is formed. The frame body 19 is connected via a shaft rod 23 to a truck 22 provided outside the furnace so as to be able to slide freely on rails 21, 21. Since the endless chain 26 is connected to the endless chain 26, the endless chain 26 is rotated by a motor (not shown) to move the cart 22 onto the rail 2.
1 and 21, the frame 19 moves in the furnace width direction. The frame body 19 has a cross section as shown in FIG. 6, so the wheel rail 1
0 or on each wheel 27 of the movable wheel rails 11, 13 without falling off.

As shown in FIG. 3, communication ducts 28 and 29 are provided at corresponding portions of the furnace body 1 between the parallel outward path 4 side and the backward path 5 side to exchange the atmospheres in each furnace. A motor 3 is mounted on the ceiling of the heat exchange chamber 30 on the outgoing path 4 side where the communication ducts 28 and 29 are provided.
A fan 32 rotationally driven by 1 is provided,
The furnace atmosphere is sucked from the heat exchange chamber 33 on the return path 5 side through the communication duct 28, and the furnace atmosphere is circulated as shown by arrows in the figure.

On the inlet side of the heat exchanger chamber 30, there is formed a front chamber 36 partitioned by doors 34, 35 and having a volume for one heat object. The atmosphere of the heat exchange chamber 30 is supplied to the front chamber 36 through a communication pipe 37 in a timely manner, and the gas in the front chamber 36 is discharged to the outside of the furnace through an exhaust pipe 38 in a timely manner. There is. On the exit side of the heat exchange chamber 30, there is formed an intermediate chamber 41 partitioned by doors 39 and 40, which also has a capacity for one object to be heated, and the atmosphere of the heating chamber 42 is contained in the intermediate chamber 41. The atmosphere in the intermediate chamber 41 is timely supplied through the communication pipe 43 and exhausted to the outside of the furnace through the exhaust pipe 44. As shown in FIG. 4, a radiant tube 45 is disposed within the heating chamber 42, and a fan 46 is provided on the ceiling to stir the atmosphere within the furnace. 47 is a door that separates the heating chamber 42 from a direction changing section. Reference numeral 48 denotes a soaking chamber formed on the outgoing path 5 side, which is separated from the direction change section by a door 49, and between it and the heat exchange chamber 33 is an intermediate chamber 52 partitioned by doors 50 and 51. It is formed. A radiant tube 53 (or cooling pipe) is disposed in the soaking chamber 48, and the atmosphere inside the soaking chamber 48 is stirred by a fan 54 provided on the ceiling. The atmosphere of the soaking chamber 48 is supplied to the intermediate chamber 52 through the communication pipe 55 as appropriate, and the atmosphere within the intermediate chamber 52 is exhausted to the outside of the furnace through the exhaust pipe 56 as appropriate. A rear chamber 59 partitioned by a door 57 and a door 58 is formed on the outlet side of the heated object of the heat exchange chamber 33 , and the atmosphere inside the heat exchange chamber 33 is communicated with a communication pipe 60 in the rear chamber 59 .
The gas in the rear chamber 59 is timely discharged to the outside of the furnace through the exhaust pipe 61. Others 62 are movable carts on which objects to be heated are placed; 63 and 64 are standby tables provided outside the bent furnace; the furnace wall openings 65 and 66 connected to the standby tables are normally closed by doors 67 and 68. has been done. Note that the doors 34, 35, 39, 40, 47, 49, 50,
51, 57, 58, 67, and 68 all slide upward or downward to open and close.

Next, the operating conditions of the roller hearth type continuous furnace configured as described above will be explained. When charging the object to be heated into the heat exchange chamber 30, the door 34 is opened with the door 35 closed, and the transport rollers of the charging table 7 and the transport rollers in the small chamber 36 are driven to rotate.
One object to be heated is carried into the chamber 6 and the door 34 is closed. After replacing the air in the small chamber 36 with ambient air supplied through the communication pipe 37, the door 35 is opened and the object to be heated is carried into the heat exchange chamber 30. In the heat exchange chamber 30, the object to be heated is heated by the atmosphere that is circulated from the other heat exchange chamber 33 via the communication ducts 28, 29. Then, with the door 40 closed, the door 39 is opened, and the object to be heated that has passed through the heat exchange chamber 30 is carried into the intermediate chamber 41, and the door 39 is closed, and the atmosphere of the heating chamber 42 is transferred to the intermediate chamber through the communication pipe 43. 4
After the atmosphere in the intermediate chamber 41 is replaced by introducing the heated object into the heating chamber 42, the door 40 is opened and the object to be heated is carried into the heating chamber 42. In the heating chamber 42, the object to be heated is heated to a predetermined temperature by blowing hot air using the radiant tube 45 as a heat source. Then, the rear door 47 is opened and the heated object is removed from the elevating frame 15, 1.
5. Move to the position directly above and stop. Therefore, the lifting platform frames 15, 15, .
3 are raised to the same height level as the wheel rails 10, 10, respectively, and the frame body 19 is slid onto the movable wheel rails 13, 13 and the wheel rails 10, 10 by the circumferential movement of the endless chain 26, thereby forming the movable wheel rails. Stop on 11,11. Thereafter, the elevating frames 15, 15, . Then, after raising the elevating platform frames 17, 17...... and lifting the object to be heated from above the frame body 19, the frame body 1
9 is further retreated to accommodate it in the small chamber 20, and the elevating frame 17, 17...... is lowered, the object to be heated can be transferred onto the conveying rollers 2, 2...... on the return path 5 side. Can be done. Therefore, the object to be heated is carried into the soaking chamber 48 by opening the door 49, and is then carried into the soaking chamber 48.
8, the object to be heated passes through the intermediate chamber 52 by opening the door 50.
After the atmosphere is replaced, the heat exchanger is transported to the heat exchange chamber 33. In the heat exchange chamber 33, this object to be heated is cooled by the atmosphere blown in from the communication duct 29, and the atmosphere whose temperature has been increased by the cooling is returned to the heat exchange chamber 30 through the communication duct 28, and the heat exchange chamber 30 is It is used to preheat the object to be heated that passes through it. The object to be heated that has passed through the heat exchange chamber 33 is carried into the rear chamber 59, and similarly to the front chamber 36, it is taken out onto the extraction table 8 with almost no atmosphere flowing out.

As described above in the embodiments, the roller hearth type continuous furnace according to the present invention is provided with a communication duct in which the parallel outgoing and returning sides of the furnace body, which is U-shaped in plan, correspond to each other to exchange the in-furnace atmospheres. By doing so, heat exchange chambers are formed respectively, and doors are provided on the inlet and outlet sides of both heat exchange chambers so that the atmosphere in both heat exchange chambers cannot freely flow outside the furnace and into the heating chamber or soaking chamber. Therefore, the efficiency of heat exchange between the objects to be heated passing through both heat exchange chambers is greatly improved. In other words, if the door is closed, high-temperature atmosphere will not flow into the heat exchange chamber from the heating chamber or soaking chamber, and the atmosphere will not flow out from the heat exchange chamber to the outside of the furnace. The temperature of the object to be heated on the outward journey is increased to completely correspond to the amount of temperature decrease on the return journey. Moreover, unlike the heating chamber and the soaking chamber, both heat exchange chambers can be provided with a desired atmosphere, so they can be effectively used for non-oxidation heat treatment, non-decarburization treatment, and the like.

In short, according to the present invention, in conventional energy-saving continuous furnaces of this type, the flow of the atmosphere in the furnace in the direction of the furnace length is prevented, but the flow is prevented by providing doors for each furnace, and the roller hearth type Since it adopts a conveyance mode, thermal efficiency is further improved and it can greatly contribute to energy saving.

[Brief explanation of the drawing]

The drawings show an embodiment of the continuous furnace according to the present invention, in which Fig. 1 is a horizontal sectional plan view, Fig. 2 is a partially enlarged view thereof, and Fig. 3 is a sectional view taken along the line X-X of Fig. 1. ,
Figure 4 is a sectional view taken along the Y-Y line in Figure 1, and Figure 5 is a cross-sectional view of Figure 1.
A sectional view taken along the Z-Z line in the figure, and FIG. 6 is a sectional view of the frame. DESCRIPTION OF SYMBOLS 1... Furnace body, 2... Conveyance roller, 3... Heat target, 4... Outgoing path, 5... Return path, 9... Direction changing device, 28, 29... Communication duct, 30, 33...
Heat exchange room, 34, 35, 39, 40, 50, 5
1,57,58...door, 36...front room, 41,5
2...middle chamber, 59...rear chamber.

Claims (1)

[Claims] 1. A furnace body that is U-shaped in plan is constructed, and conveyor rollers for moving the object to be heated are laid in the furnace body to form parallel outward and return paths. It is equipped with a direction changing device that moves the heated material from the side to the return side, and a communication duct is provided in the corresponding part of the parallel outbound side and return side of the furnace body to exchange the atmospheres inside the furnace, thereby achieving heat exchange. A door is provided on the inlet side and the outlet side of the heated object of both heat exchange chambers to prevent the atmosphere inside the furnace from flowing in the direction of the furnace length. This is an energy-saving roller hearth type continuous furnace.