KR20020052059A - Overheating protection apparatus of the slab edge in reheating furnace - Google Patents

Abstract

PURPOSE: An apparatus for preventing overheating of the front part of a material to be heated in a reheating furnace is provided to prevent overheating of the front part of the material to be heated during change-over combustion in a regenerative burner combustion system adopted to the reheating furnace. CONSTITUTION: In a reheating furnace consisting a blower(21), a plurality of switching valves, regenerators(28,29,45,46), burners(30,31,41,42), a suction fan(32), a furnace(33), fixed beams(35), and moving beams(36), the apparatus for preventing overheating of the front part of a material to be heated in the reheating furnace comprises porous plates(37,38) for preventing overheating of the front part which are installed at upper and lower parts on the inner wall of the furnace(33) between the burners(30,31); and porous plates(39,40) for preventing overheating of the front part which are installed at upper and lower parts on the inner wall of the furnace(33) between the burners(41,42), wherein each of the plates(37,38,39,40) for preventing overheating of the front part is a semi-cylindrical plate on which grooves for dropping pollution particles and grooves for sucking combustion gas are formed.

Description

Overheating protection apparatus of the slab edge in reheating furnace

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preventing overheating of the tip end portion of a material to be heated, and more particularly, to an apparatus for preventing overheating of the tip (both ends) of a material to be heated in heating furnaces and various industrial furnaces to which a regenerative combustion system is applied.

1 is a configuration diagram of a heating furnace employing a conventional regenerative burner combustion apparatus, in which the right burners 2 and 3 are in combustion mode and the left burners 8 and 9 are in exhaust mode as shown in FIG. As the case is shown, the right front end of the material to be heated 14 is always exposed to the portion closest to the flame, causing a problem in that the central portion of the material to be heated 14 and the temperature deviation are severely generated.

When the right burners 2 and 3 are in the exhaust mode after a predetermined period (30 seconds to 3 minutes), the left burners 8 and 9 are switched to the combustion mode and combustion occurs. The left end of (14) is exposed to the position closest to the flame, causing a problem that a temperature deviation (50-100 ° C.) with the center of the material to be heated 14 occurs.

Figure 5 shows the temperature deviation of the center portion and the tip portion of the raw material in the conventional heating furnace, it can be seen that the temperature deviation of the material extracted from the final heating furnace shows a deviation of approximately 50 ℃. As described above, the temperature of the left and right ends of the material to be heated 14 is overheated as compared with the temperature of the center part while the switching combustion is performed with a predetermined period (30 seconds to 3 minutes). The material to be heated 14, which is supported by the fixed beam 15 and extracted by the moving beam 16, is not rolled properly in a subsequent rolling process so that a bending phenomenon occurs in the material. The serious problem of falling error rate is caused.

The present invention has been invented to solve various problems caused by a heating furnace employing a conventional regenerative burner combustion device in view of the above situation, and the tip portion of the material to be heated when switching combustion in the regenerative burner combustion device used in a heating furnace and the like. It is an object of the present invention to provide a temperature overheating prevention device at a tip of a material to be heated in a furnace to prevent overheating.

1 is a configuration diagram of a heating furnace employing a conventional regenerative burner combustion apparatus,

2 is a configuration diagram of the temperature overheat prevention device at the tip of the material to be heated in the present invention,

3 is a cross-sectional view of the perforated plate for preventing temperature overheating according to the present invention;

4 is a view showing an embodiment of the present invention,

5 is a temperature distribution diagram of a raw material in a conventional heating furnace,

6 is a material temperature distribution diagram according to an embodiment of the present invention.

<Explanation of symbols for main parts of drawing>

1: Low 2,3: Right burner

4,5: Right fuel nozzle 6,7: Right heat accumulator

8,9: Left burner 10,11: Left fuel nozzle

12,13: left heat storage 14: material

15: fixed beam 16: moving beam

21: blower

22, 23, 24, 25, 26, 27, 43, 44, 47, 48, 49, 50

28,29,45,46: Regenerator 30,31,41,42: Burner

32: suction fan 33: furnace

34 material 35 fixed beam

36: moving beam

37, 38, 39, 40: perforated plate for preventing tip overheat

60: semi-cylindrical plate

61: groove for dropping stain particles 62-groove for suction of combustion gas

In order to achieve the above object, the apparatus for preventing overheating at the tip of the material to be heated in the heating furnace of the present invention includes a blower 21 and a switching valve 22, 23, 24, 25, 26, 26 27, 43, 44, 47, 48, 49, 50, regenerators 28, 29, 45, 46, burner 30, In the heating furnace consisting of (31), (41), (42), suction fan (32), furnace (33), fixed beam (35) and moving beam (36), the burners (30), (31). The upper and lower ends of the perforated plates 37 and 38 for preventing overheating are installed on the inner wall of the furnace 33, and the tip temperature is raised and lowered on the inner wall of the furnace 33 between the burners 41 and 42. It is characterized in that the overheat prevention porous plates 39 and 40 are provided.

The perforated plates 37, 38, 39, and 40 for preventing the end of temperature overheating are semi-cylindrical plates 60, each of which has a groove 61 for contaminating particles and a groove 62 for intake of combustion gas. It is.

Hereinafter, with reference to the accompanying drawings will be described in detail the operation of the temperature overheat prevention device of the tip portion of the material to be heated in the present invention.

2 is a configuration diagram of a tip end temperature overheating prevention device of a material to be heated in a heating furnace of the present invention, FIG. 3 is a cross-sectional view of a porous plate for preventing tip end temperature overheating according to the present invention, and FIG. 4 is a view showing an embodiment of the present invention. , The combustion air at room temperature supplied by the blower fan 21 in the combustion mode of the burners 30 and 31 is stored in the regenerator 28 by opening the combustion air switching valves 23 and 23. The high temperature combustion air (800 ° C. or more) supplied to the burners 30 and 31 through the 29 is supplied by opening the fuel switching valves 24 and 25 and injected through the fuel nozzle. Combustion with the fuel is achieved.

The combustion gas in the furnace 33 heats the material to be heated 34 which is placed on the fixed beam 35 and the moving beam 36 and burners 41 and 42 which are in the exhaust mode by the suction fan 32. After passing through the heat accumulators (45) and (46), the heat dissipates to the state of low temperature (200 ° C or less), and then passes through the combustion exhaust gas switching valves (47) and (48) to the atmosphere through the suction fan (32). Exhausted.

At this time, in order to prevent overheating of the right front end portion of the material to be heated 34 corresponding to the distance between the burners 30 and 31 between the right burners 30 and 31 and the material to be heated 34. By installing the perforated plates 37 and 38 having a length of overheat prevention up and down, the hot flame region and combustion gas generated from the right burners 30 and 31 do not directly touch the right end of the material to be heated 34. The upper and lower portions of the right end of the material to be heated 34 have an effect of preventing overheating.

In addition, in order to prevent overheating of the left end portion of the material to be heated 34 corresponding to the distance between the burner 41, 42 between the burner 41, 42 and the material to be heated 34. By installing the perforated plates 39 and 40 having a length of overheat prevention up and down, the hot flame region and combustion gas generated from the left burners 41 and 42 do not directly touch the left end of the material to be heated 34. The upper and lower portions of the left end of the material to be heated 34 have an effect of preventing overheating.

And the characteristic of the regenerative combustion is the high speed part, so as shown in FIG. 3, which is a detailed view of the overheat preventing plates 37, 38, 39, and 40, the furnace (62) through the combustion gas suction groove (62). 33) Combustion gas inside is sucked into the combustion zone, and the oxygen concentration decreases, so that the maximum flame temperature can be suppressed and the nitrogen oxide can be suppressed.

In addition, the overheat prevention plate is a semi-cylindrical plate 60 having a semi-circular cross-sectional shape so that deposits of the contaminated particles accumulated on the overheat prevention plate by the contaminated particle drop groove 61 of FIG. 3 can freely fall. The plate is made of alumina capable of withstanding high temperatures up to 1,300 ° C.

6 is a temperature distribution diagram of a material according to an embodiment of the present invention, in which a furnace is 1050 ° C., 1100 ° C., and 1080 ° C. in a furnace consisting of three preheating zones 13M, a heating zone 11M, and a crack zone 9M, respectively. In this case, the heat-resistant data measuring system is mounted on the material to be heated (250mmH × 2000mmW × 4000mmL) and shows the temperature history of the center and tip when low temperature operation is performed for about 248 minutes.

It can be seen from FIG. 6 that the temperature deviation of the center portion and the tip portion of the material to be heated is uniform within 10 ° C. during material extraction in the final heating furnace.

The present invention that acts as described above can prevent overheating of the tip end portion of the heated material generated during heating of the material to be heated in the regenerative combustion device employed in the heating furnace, as well as the error rate of the product due to the uniform heating effect of the material. There is an advantage to increase.

Claims (2)

Blower 21 and multiple switching valves, heat storage 28, 29, 45, 46, burner 30, 31, 41, 42, suction fan 32 In the heating furnace consisting of a furnace 33, a fixed beam 35 and a moving beam 36, a perforated plate for preventing the temperature overheating at the tip end up and down on the inner wall of the furnace 33 between the burners 30, 31 (37) and (38), and the perforated plate 39, 40 for preventing the tip overheating up and down on the inner wall of the furnace (33) between the burners (41) and (42). Temperature overheating prevention device at the tip of the material to be heated in the furnace. The perforated plates 37, 38, 39, and 40, respectively, for preventing tip overheating are semi-cylindrical plates 60. A device for preventing overheating at the tip end portion of a material to be heated in a furnace, characterized in that a groove (62) is formed.