JPS6037862B2 - Burner arrangement method for vertical continuous annealing furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of arranging burners in a vertical continuous blunting furnace which is particularly suitable for blunting special steel strips such as stainless steel.

Tokubuta No. 52-50900 (Japanese Unexamined Patent Publication No. 53-1989)
No. 1135808) The invention has a structure in which steel plate strips are continuously charged into the furnace through a slit-like entrance provided in the upper furnace lid, and the hanging steel plate strips are heated and damped while forming a free loop in the furnace. The invention is characterized in that no hearth rollers are installed in the furnace to guide the steel strips.Furthermore, in a related invention, a refractory wall is suspended from the furnace lid to heat the strips on the inlet and outlet sides. It is clear that it is constructed so that it can be moved toward the furnace wall side so as not to interrupt the hanging of the strip loop and to prevent the drawing of molten metal.

Conventional continuous Akyo blunting furnaces for steel plate strips are vertical and require hearth rollers to guide the steel strips as they move up and down.
Since it was 0qC, the hearth roller was able to withstand this, but the stainless steel brick hammer was 800~
It is extremely high pitched at 1000qo, and installing a hearth roller has a problem with the build-up of the scale, so it is 1000qo.
The invention of the same issue had a remarkable effect in that it came up with a vertical furnace that did not require a hearth roller at all, although there was a problem in that it had to use the largest horizontal tunnel furnace, such as the one with 18 skins. However, the invention does not specifically specify the arrangement of the combustion burners, and the embodiments only state that they are arranged around the furnace, and the drawings do not show a situation in which they are arranged perpendicularly and in one row on both sides of the hanging wall. There is. However, subsequent experiments revealed that this arrangement of combustion burners was insufficient, and the present invention is intended to solve this problem. The present invention is directed to a vertical continuous anchor furnace in which steel plate strips are charged and discharged from the upper slit-shaped bag inlet and outlet and heated while forming a free loop in the furnace. In the horizontal direction, the steel plate strip is sandwiched and shifted so that the combustion gas in the shape of a mirror cylinder is swirled at approximately equal distances from the front and back surfaces of the anchor steel plate strip to be burned, forming a catenary-like free loop. A method of arranging burners for a vertical continuous anchor furnace, characterized in that the combustion burners are arranged so as to face each other, and in the vertical direction, at the maximum interval that satisfies the requirement that no uneven heat is generated in the length direction of the steel plate strip. be.

The present invention will be further explained based on embodiments shown in the drawings. 1st
The figure is a vertical elevational view vaguely illustrating an apparatus for carrying out the present invention;
FIG. 2 is a cross-sectional plan view of FIG. 1.

In the figure, 1 is a heating chamber of a vertical continuous twilled anchor furnace, 2 is an internal partition wall arranged at the upper end of the chamber, and 3 is a heating chamber that hangs down from the partition wall 2 in a T-shape. 1 into a heating zone 1' and a soaking zone 1''.

The horizontally conveyed steel strip 4 is deflected by 90 degrees by the charging side deflector pinch rolls 5 and fed into the heating chamber 1 through the steel strip charging groove 2' of the internal cut wall 2. The strip is inserted into the heating zone 1', rotates in a free loop at the bottom of the heating chamber 1, ascends around the hanging wall 3, and is discharged from the steel strip discharge groove 2'' of the internal partition wall 2. The steel sheet strip 4 is then conveyed horizontally by the deflector pinch roll 6 on the discharge side by 90 degrees, and then pulled out and conveyed in the horizontal direction.
Because it is heated to a high temperature of ~1,000 pm, its rigidity decreases and it becomes soft, forming a free loop close to a perfect catenary curve according to gravity.

Therefore, if the combustion burner is arranged vertically parallel to the furnace wall of the heating chamber, the heating effect will be reduced, partly because the flame will be farther away from the strip 4, and partly because the flame will impinge directly on the strip 4, causing the strip 4 to There is deterioration and desertion. It is important to have a stable swirling flow around the entire circumference of the strip in order to make the temperature distribution uniform in the width direction of the strip.

As a method of creating a swirling flow, for example, heating zone 1' shown in FIG.
, 8 and 10, respectively, in the horizontal section of the soaking zone 1'' (Fig. 2).
It is conceivable to create a high-speed jet using each burner, but this method requires local heating of opposing wall surfaces, and reduces the temperature of the combustion gas turning, resulting in an unfavorable temperature distribution in the width direction of the strip. arise. For this reason, in the present invention, by arranging the burners 7, 8 and 9, 10 facing each other with the steel plate strip 4 sandwiched therebetween and at different positions, it is not necessary to use a high-speed jet flow that locally heats the wall facing the burners. Furthermore, the distribution of combustion gas compensates for the temperature distribution on the front and back surfaces of the strip, making it possible to maintain a uniform temperature in the width direction of the strip. In the present invention, the distance between the strip and the burner center is preferably approximately 300 to 50 m. Next, we will discuss the burner arrangement above and below the furnace.

In order to prevent uneven heat from occurring in the lengthwise direction of the strip, it is better to provide as many as 4-4 spacing in the upper and lower directions as possible, but if it is unnecessarily large, it is economically disadvantageous in terms of equipment costs and fuel consumption. It is.

It is best to take this point into consideration when arranging the device appropriately. For example, 5
00 to 1500 ribs is preferred. Furthermore, the burners 7, 8 and 9, 10 on both sides of the strip 4 do not necessarily have to face each other at the same height or have the same number; Any arrangement may be used as long as it can form a continuous combustion gas flow in the shape of a blind cylinder that rises or descends in a tornado shape. In the present invention, by arranging the combustion burner as described above, there is no risk of burning out the steel plate strip, and the heating bowl can be dulled most efficiently.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional elevational view schematically illustrating an apparatus for carrying out the present invention, and FIG. 2 is a cross-sectional plan view of FIG. 1. 1... Heating chamber, 2... Internal partition wall, 3...
...Takudo, 4... Steel plate strip, 5;
6... Bag entry side and discharge side deflector pinch rolls, 7, 8, 9, 10... Combustion burner. Hiiragi' drawing rare z drawing

Claims (1)

[Claims] 1. In a vertical continuous annealing furnace for steel plate slips, which are charged and discharged from the upper slit-shaped charging inlet and outlet, and are heated and annealed while forming a free loop in the furnace, a nearly catenary-shaped free loop is formed in the vertical direction. In order to swirl the cylindrical combustion gas at approximately the same distance from the front and back surfaces of the annealed steel strip forming a loop, the steel strips are sandwiched in the horizontal direction and shifted in position so that they face each other, and in the vertical direction. A burner arrangement method for a vertical continuous annealing furnace is characterized in that combustion burners are arranged at the maximum interval that satisfies the requirement that uneven heat is not generated in the length direction of a steel plate strip.