JP3174148B2 - Furnace equipment for heating and soaking high-temperature slabs - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-temperature slab heating and soaking furnace equipment between a continuous casting step and a rolling step.

[0002]

2. Description of the Related Art In a recent iron and steel process, an attempt has been made to make a continuous casting facility and a rolling facility continuous to continuously perform a continuous casting-rolling. However, there are problems that must be solved in terms of quality, such as increasing the cost of slabs at the continuous casting facility, increasing the heat retention at the transport facility, and the quality of the process. Is in the stage of. Generally, hot charge slab is put into furnace equipment (heating furnace, soaking furnace, etc.) once and then heated and soaked to within the temperature and temperature deviation required by the rolling equipment. Has been taken.

[0003] Although a large reduction in fuel consumption rate can be realized by the hot charge operation, an operation method different from that of a conventional furnace for heating a cold piece for further energy saving,
For example, Japanese Patent Publication No. 58-17243 and Japanese Patent Publication No. 58-1840
1 has been proposed. These proposals aim to improve the accuracy of estimating the charging temperature of the slab and reduce the unit fuel consumption by reflecting it in the furnace temperature control.In terms of the furnace profile and burner arrangement, the conventional It was the same as the furnace equipment.
In other words, the flow of the combustion exhaust gas from the burner is orthogonal to the direction in which the slab travels in the furnace, so that the furnace atmosphere temperature on the charging side is lower than that on the extraction side.

[0004]

The inventor of the present invention has found that, for a high temperature slab having a temperature distribution with a low surface temperature and a high internal temperature, the atmosphere temperature in the furnace on the charging side is high and the furnace is moved toward the extraction side. It has been found that the condition is that the internal atmosphere temperature decreases and becomes approximately the same as the slab surface temperature. In the prior art, such an atmosphere temperature pattern in the furnace could not be obtained, resulting in an excessively large furnace facility scale, which was not optimal in terms of energy saving. The present invention has been made in view of the above points, and aims to provide a furnace facility for rapidly increasing the surface temperature of a high-temperature slab and realizing a furnace atmosphere temperature pattern for performing efficient heating and soaking. is there.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a burner is installed in a furnace facility on the side where a high-temperature slab is charged, and a flow of combustion exhaust gas from the burner is made parallel to a direction in which the slab travels in the furnace to extract a high-temperature slab. A flue gas inlet for guiding flue gas to the chimney is provided on the side.

[0006]

The operation will be described based on the transition of the temperature of the high-temperature slab in FIG. The surface B and C of the high-temperature slab having the temperature distribution shown in FIG. 3 charged into the furnace equipment are rapidly heated by the burner installed on the charging side. The temperature A inside the high-temperature slab temporarily lowers due to the heat transfer to the surface, but the surface is rapidly heated, so that the heat transfer stops, and conversely, the temperature A rises due to the heat transfer from the surface.

[0007] As the high-temperature slab is conveyed in the furnace to the extraction side, the combustion heat from the charging burner is taken away by the slab and the refractory material in the furnace, the furnace atmosphere temperature decreases, and the slab surface temperature increases. Is almost the same as For this reason, the surface temperatures B and C that have rapidly risen gradually decrease, and the temperature deviation from the internal temperature A that has risen due to the heat from the surface decreases, and a soaking distribution can be obtained.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiment shown in FIG. The high-temperature slab 2 sent to the furnace equipment by the out-of-furnace table 1 is charged into the furnace from the inlet 3 by the in-furnace table 4. A burner 5 is installed on the front wall before charging, and the combustion exhaust gas from the burner flows toward the extraction port 6. The high-temperature slab is conveyed in the furnace by a walking beam, a walking hearth, or the like, and is sent to the extraction furnace table 7. The slab is extracted to the out-of-furnace rolling line by the extraction furnace table. A flue gas inlet 8 is provided on the extraction side, and the combustion exhaust gas from the burner is exhausted to the chimney through this flue gas inlet. FIG. 4 is a comparative example showing a conventional furnace profile and a furnace atmosphere temperature pattern.

[0009]

The inventor estimated and compared the time required to heat and soak the slab having the temperature distribution shown in FIG. 3 with the prior art and the present invention. As a result, while the conventional technology requires 35 minutes, the technology of the present invention can reduce the time by about 40% to 20 minutes.

[0010] It has been confirmed that the shortening of the time makes it possible to reduce the scale of the furnace equipment, reduce the amount of fixing and heat loss of the furnace body and the like, and bring about a great effect in terms of energy saving of equipment costs.

[Brief description of the drawings]

FIG. 1 is a plan view, a longitudinal sectional view and a diagram showing an atmosphere temperature in a furnace showing an embodiment of the present invention, FIG. 2 is a diagram showing a transition of a high temperature slab temperature, and FIG. 3 is a diagram showing a high temperature slab temperature distribution at the time of charging. FIG. 4 is a longitudinal sectional view showing a longitudinal section and a diagram of an atmosphere temperature in a furnace showing an embodiment of the prior art.

[Explanation of symbols]

1: Out-of-furnace table, 2: High-temperature slab, 3: Inlet,
4: Inlet furnace table, 5: Burner, 6: Extraction port, 7: Extraction furnace table, 8: Flue inlet.

Claims (1)

(57) [Claims] In a furnace facility for heating and soaking high-temperature slabs from a continuous casting facility between a continuous casting step and a rolling step, the slabs are heated and soaked only on the charging side of the furnace body. Furnace equipment for heating and equalizing high-temperature slabs, which is equipped with a burner that performs heating and a flue inlet on the extraction side.