KR100642606B1 - Furnace for heating slab - Google Patents

Abstract

An object of the present invention is to provide a heating furnace capable of minimizing the opening of a heating furnace in charging a slab in a heating furnace for rolling a slab.

According to the invention, the pusher 5 which pushes the heating material 7 toward the charging door 2 of the heating furnace 1, and the heating material 7 is positioned to the entrance of the charging door 2 of the heating furnace 1 In a heating furnace comprising a charging table (3) guided to guide and a plurality of skid buttons (13) provided at regular pitch intervals to seat the heating material (7), the heating material (7) in the interior of the heating furnace (1) ) Heating material which enters the inside of the heating furnace 1 by the pusher 5 in the state in which the conveying means 9 which moves the said pitch by the said pitch, and the charging door 2 of the heating furnace 1 open. A heating furnace is provided, characterized in that it comprises a supporting means on which (7) is seated.

Heating furnace, loss calories, moving beam, skid button

Description

Furnace for rolling heating slab {Furnace for heating slab}

1 is a schematic diagram showing a state in which the slab enters the heating furnace according to the prior art,

FIG. 2 is a plan view illustrating a skid beam and a skid button inside the furnace in the furnace illustrated in FIG. 1;

3 is a graph showing the temperature and the amount of oxygen in the heating furnace shown in FIG.

Figure 4 is a cross-sectional view showing a moving beam that operates to enter the slab into the charging door of the furnace shown in Figure 1,

5 is a schematic diagram showing a state in which the slab enters the heating furnace according to an embodiment of the present invention,

6 is a schematic view showing a skid beam and a skid button inside the furnace in the furnace shown in FIG.

7 is a block diagram showing a heating material charging procedure for charging the heating material in the heating furnace according to an embodiment of the present invention.

       ♠ Explanation of symbols on the main parts of the drawing ♠

  1: heating furnace 2: charging gate

  3: slab charging table 5: pusher

  7: slab 9, 109: moving beam

  13: Skid Button 15: Skid Beam

  110: pipe type skid button

The present invention relates to a heating furnace for heating while transferring slab, and more particularly, to a heating furnace that can reduce the loss of heat by minimizing the opening time of the heating furnace when the slab is charged into the heating furnace.

In general, the hot rolling furnace is divided into a pusher, a walking hearth, and a walking beam, depending on the conveying means of the charging material. According to the charging method of heating material, it is divided into a pusher and a charger.

The function of the heating furnace for hot rolling is to heat the slab so that the slab can be easily rolled, and depending on the type of the slab, the heating temperature is usually maintained at a high temperature of 1050 ° C or higher, and a large amount of slab is used by using the smallest amount of fuel. High efficiency that can be heated is required.

To this end, the furnace uses a fireproof material with good insulation or employs a method of increasing airtightness in order to reduce the amount of heat emitted through the gap of the furnace, to minimize the amount of heat generated during charging of the heating material. Also, it belongs to the method for improving the thermal efficiency of the furnace.

On the other hand, when the material, that is, slab is charged by using the pusher, when the charging slab is charged through the furnace charging door, it is necessary to extend the charging door of the heating furnace more than necessary by the operation of the moving beam and the interference of the charging door. do.

1 is a schematic view showing a state in which the slab enters the heating furnace according to the prior art, Figure 2 is a plan view showing a skid beam and a skid button in the interior of the furnace in the heating furnace shown in Figure 1, Figure 3 1 is a graph showing the temperature and oxygen amount of the furnace shown in Figure 1, Figure 4 is a cross-sectional view showing a moving beam that operates to enter the slab to the charging door of the furnace shown in FIG.

As shown in FIGS. 1 and 2, the moving beam 9 installed inside the heating furnace 1 is a device that performs a circular rotational movement, and moves a plurality of slabs 7 to the moving beam 9. It is a device that moves forward by 1 pitch after raising in a state seated on the top of the. Meanwhile, skid beams 15 are formed on the left and right sides of the moving beam 9, and a skid button on which the slab 7 can be seated on the upper surface of the skid beam 15 in units of one pitch of the moving beam 9. (13) is formed. Therefore, when the moving beam 9 is rotated once, the plurality of slabs 7 located on the upper surface of the moving beam 9 are moved forward while being seated on the skid button 13 installed at the front by one pitch.

Here, defining the one stroke motion of the moving beam 9, the process when the moving beam (9) is located at the top is referred to as one process, the maximum advanced state is two processes, and when it is located at the bottom (three processes) For example, the 4th step is when you are backing up.

On the other hand, when the slab 7 is located in front of the heating furnace 1 along the slab charging table 3 by the pusher 5, as shown in Fig. 1 (a), the moving beam 9 is Located in step 2, at this time, the charging door (2) is opened by the thickness of the slab (7) in order to maximize the internal temperature of the furnace (1).

In addition, when the moving beam 9 passes through three processes, the plurality of slabs 7 in the heating furnace are already advanced by one pitch, and as shown in FIG. 1B, the moving beam 9 In this four process, the rear end of the moving beam 9 comes out of the charging door 2 of the heating furnace 1 and comes into contact with the bottom surface of the slab 7 located above the slab charging table 3. Then, moving from the process 4 to the process 1, the moving beam 9 is raised, at this time, the charge gate (2) is raised higher because of the interference with the charge gate (2), therefore, the open charge gate ( Through 2) a large amount of heat of the furnace is lost.

As shown in FIG. 3, the change in temperature in the heating furnace 1 is continuously maintained at the target heating temperature, but it can be seen that the temperature is repeatedly decreased and increased with a certain period. In addition, the change in the concentration of oxygen present in the heating furnace 1 also forms the same cycle as the temperature pattern. Comparing the temperature pattern with the oxygen concentration pattern, the oxygen concentration increases when the temperature decreases, and the temperature It can be seen that the oxygen concentration drops as the value rises.

For this reason, as the cool air is introduced at regular intervals from the outside, it can be seen that the internal temperature of the furnace 1 decreases and the concentration of oxygen increases. And, such a temperature drop is that when the charging door 2 is opened, the internal heat flows out to lower the internal temperature of the heating furnace 1.

Table 1 shows the result table of the passion acid of the hot rolling furnace (1). As shown in Table 1, only about 47 to 52% of the heat input into the heating furnace (1) was used for heating the material, and the remaining heat was waste gas. This can lead to dissipation of the furnace body, heat transfer of the internal coolant in the furnace, and loss of heat during charging and extraction.

As shown in Table 1, the heat loss generated during charging and extraction of the heating material within the heat loss from the furnace 1 is within 3%, and the heat is radiated heat and high temperature irrespective of the presence or absence of the heat transfer medium. It consists of the release of waste gas.

That is, about 38% of this heat loss is loss heat generated at the time of charging, and especially, 86% of heat loss generated at the time of charging corresponds to heat loss due to the discharge of hot waste gas.

In general, the operation of the furnace 1 maintains the pressure in the furnace 1 slightly higher than atmospheric pressure in order to minimize the loss of heat, and adjusts the pressure by installing a damper to reduce the pressure change during the charging of the heating material. Do it.

As described above, the temperature change and the oxygen concentration change in the furnace 1 are caused by the inflow of external cold air. As shown in FIG. 4, the inflow and outflow of external air is caused by the movement of the moving beam 9 for moving the heating material at the same time as the charging door 2 is opened to charge and move the heating material. Occurs.

That is, at the moment when the charging door 2 is opened and the moving beam 9 is activated, the discharge of the hot waste gas and the inflow of external cold air occur through the open opening of the charging door 2. This is because the pressure inside the furnace is kept slightly higher than the outside atmospheric pressure to suppress the inflow of outside air and attempt to discharge some hot waste gas, so that the hot waste gas is emitted through the upper layer of the charging door 2, but the moving beam ( In the lower part of 9), when the process proceeds from step 4 to step 1 of the moving beam 9, the inflow of external air occurs due to the instantaneous pressure change on the lower side of the heating furnace 1.

On the other hand, to solve this problem, instead of charging the heating material directly into the heating furnace, adopting a method of preventing the inflow and outflow of external air by charging the heating material directly in the air with a double door structure. have. However, the structure of a heating furnace having such a double-loading door is complicated, and there is a disadvantage in the maintenance of the equipment, and also because of the characteristics of the equipment can be applied only to the billet (Billet) relatively small heating material. There is a disadvantage.

The present invention has been made to solve the problems of the prior art as described above, an object of the present invention is to provide a heating furnace capable of keeping the temperature of the interior of the furnace to the maximum by minimizing the time to open the charging door.

According to the present invention for achieving the above object, a pusher for pushing the heating material toward the charging door of the heating furnace, a charging table for guiding the heating material to the entrance of the charging door of the heating furnace, and the heating material A heating furnace including a plurality of skid buttons provided at regular pitch intervals to be seated, comprising: a conveying means configured to move the heating material by the pitch inside the heating furnace, and the charging door of the heating furnace is opened; There is provided a heating furnace including support means for seating the heating material entered into the heating furnace by the pusher.

In addition, according to the present invention, the support means is installed to maintain a distance of 10 ~ 15mm from the charging door of the heating furnace.

In addition, according to the present invention, the length of the support means is 2-3m.

In the following, with reference to the accompanying drawings, a preferred embodiment of a heating furnace for rolling the slab according to the present invention will be described in detail.

5 is a schematic diagram showing a state in which the slab enters the heating furnace according to an embodiment of the present invention, Figure 6 is a skid bin and the skid button in the interior of the heating furnace in the heating furnace shown in FIG. 7 is a block diagram showing a heating material charging procedure for charging a heating material according to an embodiment of the present invention to a heating furnace.

As shown in FIGS. 5 and 6, the slab charging table 3 is provided up to the charging door 2 of the heating furnace 1, and from the charging door 2 to about 10 to 10. A pipe-type skid button 110 having a length of about 2500 mm and having a distance of 15 mm is installed, and a skid button 13 is installed behind the pipe-type skid button 110. In addition, the stroke of the moving beam 109 for moving the plurality of slabs 7 seated on the upper surface forward by one pitch is made in the interior of the heating furnace 1.

The charging relationship for charging the slab in the heating furnace for rolling the slab configured as described above will be described in detail.

As shown in FIG. 7, with the charging door 2 fully closed, the slab 7 is pushed into the pusher 5 so that the slab 7 moves along the slab charging table 3 toward the heating furnace 1. At this time, the moving beam 109 is located in two processes (S1).

Then, the charging door (2) is opened by the thickness of the slab (7) (S2), the pusher (5) so that the slab (7) is located above the pipe-type skid button (110) installed inside the heating furnace (1). Use to slide. At this time, the moving beam 109 is located in three steps (S3).

When the slab 7 completely enters the inside of the heating furnace 1 and is seated on the upper surface of the pipe-type skid button 110, the charging door 2 is closed (S4). At this time, the moving beam 109 proceeds from three processes to four processes, and the pusher 5 moves to the rear.

In the fourth process of the moving beam 109, the rear end of the moving beam 109 is in contact with the bottom surface of the slab 7 seated on the upper surface of the pipe-type skid button 110, the moving beam 109 is 1 in 4 While proceeding to the process, the slab 7 is raised in the interior of the heating furnace 1 (S5). Then, by proceeding from step 1 to step 2 of the moving beam 109, the slab 7 is seated on the top of the skid button 13, while advancing by one pitch of the moving beam 109 (S6).

Therefore, the time when the charging door 2 is opened in this process is only when the slab 7 enters the inside of the heating furnace 1, and therefore, the heat loss of the heating furnace 1 can be reduced, As the charging gate 2 is opened, the amount of oxygen that enters the inside of the heating furnace 1 may be reduced.

As described in detail above, the rolling furnace for heating the slab of the present invention opens the charging door only when the slab enters the interior of the furnace, so that the amount of charge and extraction loss of the heating material of the furnace and the inside of the furnace There is an advantage that the amount of oxygen introduced into the furnace can be reduced to a minimum.

This can stabilize the working conditions of the furnace has the advantage of improving the quality of the product.

Although the technical idea of the rolling furnace for heating the slab of the present invention has been described above with the accompanying drawings, this is illustrative of the best embodiment of the present invention and is not intended to limit the present invention. In addition, it is obvious that any person skilled in the art can make various modifications and imitations without departing from the scope of the technical idea of the present invention.

Claims (3)

A pusher for pushing the heating material toward the charging door of the furnace, a charging table for guiding the heating material to the entrance of the charging door of the furnace, and a plurality of skid buttons installed at regular pitch intervals so that the heating material is seated. In the furnace, A moving beam made of a stroke for moving the heating material by the pitch inside the heating furnace, And a pipe-type skid button on which a heating material entered into the heating furnace by the pusher while the charging door of the heating furnace is opened. The method of claim 1, The pipe-type skid button is a heating furnace, characterized in that installed to maintain a distance of 10 ~ 15mm from the charging door of the heating furnace. The method according to claim 1 or 2, The length of the pipe-type skid button is a heating furnace, characterized in that 2 ~ 3m.

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