JPS62250115A - Continuous heat treatment furnace - Google Patents

Abstract

PURPOSE:To prevent the generation of a negative pressure near a charging port in a continuous heat treatment furnace which has a recuperator on the charging side and a partition wall in the inside by constituting the partition wall of a stationary wall and movable wall. CONSTITUTION:The partition wall 10 of the continuous heat treatment furnace having the recuperator 5 on the charging side and the partition wall in the inside is constituted of the sectionally U-shaped stationary wall 11 provided to sandwich the pass line and the movable wall 12 provided rotatably in the recess of the wall 11. The movable wall 12 is so constituted as to be turned to the charging port side by an actuator 13 provided on the furnace outside via a gear train 13. The actuator 13 is driven via a controller 16 by a fuel flow rate of a heating zone and via a controller 17 by the furnace pressure near the charging port.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a four-sequence heat treatment furnace equipped with partition walls.

[Prior Art] Conventionally, for example, in a three-way continuous heating furnace consisting of a pre-heating zone 1, a heating zone 2, and a soaking zone 3 as shown in Fig. 7, a flue 4 from the charging side was used.
Among them, there is one that is equipped with a recuperator 5 and a furnace pressure control chamber 4'6, and discharges the exhaust gas from a chimney 7. In this type of heating furnace, a partition 910'r is provided between the preheating zone 1 and the soaking zone 2, for example, as an energy saving measure.

In this case, the furnace pressure is controlled by detecting the pressure in the soaking zone 3 and adjusting the furnace pressure to the set value using the furnace pressure regulator 8f! ! : Via damper 6
is being adjusted.

[Problems to be solved by the invention] In this case, the pressure distribution in the furnace length direction changes depending on the combustion gas flow rate, and as shown in FIG. 8, the pressure is maintained at positive pressure in the heating zone 2 and the soaking zone 3. However, when the combustion gas flow rate is large, the pressure becomes negative in the vicinity of the charging inlet of the preheating zone 1. This is because the pressure loss caused by the partition wall 10 increases as the amount of combustion gas flow increases. The negative pressure near the charging port is designed to induce air to enter from the charging port, reducing the efficiency of the recuperator 5.

The object of the present invention is to provide a nine-continuous heat treatment furnace that can solve the above-mentioned problems.

[Means and operations for solving the problem] In a continuous heat treatment furnace that is equipped with a recuperator on the charging side and has a partition wall inside the furnace, the partition wall is constituted by a fixed wall and a movable wall.

In this way, by rotating the movable wall depending on the flow rate of the combustion gas and adjusting the opening area of the partition wall, the furnace pressure near the charging port is prevented from becoming negative pressure.

[Example 1] An example of the present invention will be described below with reference to FIGS. 1 to 3. Here, the same parts in the drawing are denoted by the same reference numerals, and the detailed explanation thereof will be omitted for the same parts as the conventional one shown in FIG. The partition wall 10 is composed of a fixed wall 11 having a U-shaped cross section and provided to sandwich a /4 line, and a movable wall 12 rotatably provided in a recess of the fixed wall.

Note that the product of 0TJiEl + Iki of the wall is set to such an extent that the furnace pressure on the pre-heating zone side of the partition wall does not become a negative pressure, and care is taken so that the original purpose of the partition wall is not impaired to the minimum. Further, the surface of the movable wall preferably has a high emissivity, and the inside of the wall may be water-cooled. The movable wall 12 is rotated toward the charging port side through an actuator 13 and a gear train 14t, which are installed outside the furnace. Actuator 1
3 is the heating zone fuel IN, t via the controller 16,
It is also driven by the furnace pressure near the charging port via a regulator 17t.

Then, the movable wall 12t is operated according to the flow shown in Figure I@4. The pressure loss due to the partition wall is calculated in advance according to the fuel flow rate in the heating zone, that is, the amount of combustion gas, and the data is compiled into a table.The opening degree of the movable wall 12 is tentatively determined from the fuel flow rate in the heating zone, and the opening/closing operation is performed. conduct. Furthermore, after operation, the opening degree of the am can be finely adjusted so that the furnace pressure near the charging port becomes the set furnace pressure.

On the other hand, conventional furnace pressure control uses a damper 6 to control the furnace pressure in the soaking zone.
This is done with the opening degree of ty4.

In this way, the furnace pressure distribution in the furnace length direction can be controlled almost uniformly even if the combustion gas flow fluctuates. That is, even without changing the set pressure of the soaking zone, the pressure near the charging port of the preheating zone is approximately ±011111 H2O, and the air entering from the charging port is suppressed to a minimum. Also, there is almost no combustion gas blowing out.

Furthermore, since the movable wall rotates toward the preheating zone, radiant heat can be used effectively, so there is almost no deterioration in the original function of the partition wall. Since the combustion gas is constricted by the upper and lower movable walls, the gas flow rate increases and the efficiency of the recuperator can be increased, preventing the combustion gas from flowing toward the ceiling in the preheating zone and effectively preheating the material. It can be carried out.

In this way, the fuel consumption rate is 250 x 10sKca4/
It is possible to reduce the basic unit by 2 to 3% with T's continuous heating furnace.

Note that the above embodiment describes a case in which a partition wall is installed between the preheating zone and the heating zone, but this invention is for reducing the pressure loss before and after the partition wall, and The location is not limited to the preheating zone in the furnace length direction, and may be provided at multiple locations.

In addition, in the above embodiment, the opening degree of the movable wall is preset by the fuel flow rate in the heating zone, and then the opening degree is finely adjusted by the furnace pressure near the charging port. The opening degree of the movable wall may be controlled by pressure.

Further, the present invention is not limited to the continuous heating furnace for steel billets shown in the examples, but can also be applied to various continuous heat treatment furnaces.

Next, a second embodiment of the partition wall 10 will be described with reference to FIG. In this case, a movable wall 22 having a size similar to the recess 21ht is rotatably provided on the charging port side of the fixed wall 21 having a U-shaped cross section. This movable wall 22 is also adapted to be rotated toward the loading port side in the same manner as the movable wall 12 in FIG. 3.

In this way, the same effects as in the first embodiment described above can be obtained.

Further, a third embodiment of the partition wall 10 will be explained with reference to FIG. This is a fixed wall 31 with a rectangular cross section and a rectangular window 3.
Open multiple 1& and move kJl in this window! 32t - is rotatably arranged and configured. In this case as well, by rotating the movable wall according to the fuel flow rate, it is possible to prevent the furnace pressure near the charging port from becoming negative pressure.

[Effects of the Invention] The continuous heat treatment furnace of the present invention as described above can prevent the furnace pressure near the charging port from becoming negative pressure without impairing the original function of the partition wall.

[Brief explanation of drawings]

Figures 1 to 4 show a failed embodiment of the present invention, with Figure 1 being an overall explanatory diagram, Figure 2 being an explanatory diagram of a partition wall, and Figure 3 being an explanatory diagram of a drive mechanism for a movable wall. Fig. 4 is an explanatory diagram of the operation flow of the movable wall, Figs. 5 and 6 are explanatory diagrams of the second and third embodiments of the partition wall, respectively, and Fig. 7 is an explanatory diagram of the conventional continuous heating furnace. The schematic diagram, FIG. 8, is an explanatory diagram of the furnace pressure distribution in all furnace configurations. 5... Recuperator, 10... Partition 11, i 1
．． 21. 3. Fixed wall, 12,22.32... Movable wall. Applicant's agent Patent attorney Takeshi Suzue 2 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. A continuous heat treatment furnace equipped with a recuperator on the charging side and having a partition wall inside the furnace, characterized in that the partition wall is constituted by a fixed wall and a movable wall.