JPS61174311A - Method for cooling body of converter - Google Patents

Abstract

PURPOSE:To prevent the deformation of the iron shell of a converter by directly blowing gas on the body of the converter from a large number of nozzles arranged around the body of the converter to drop the temp. of the body to <=400 deg.C. CONSTITUTION:The body of a converter is covered with a trunnion ring 2, and a large number of united nozzles 5 are exchangeably arranged in the ring 2 through a sleeve 7 and a trunnion inspection window in a direction perpendicular to the body of the converter. Gas is directly blown on the whole region of the body of the converter from the nozzles 5 to cool the body.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for cooling the abdomen of a converter furnace body to prevent thermal deformation of the body.

(Prior Art) The converter furnace body is exposed to high temperatures during operation, and if it becomes deformed due to thermal stress during repeated use, it becomes unusable. Conventionally, in order to prevent this deformation,
The method described in FIG. 9 is known.

Method (4) of directly welding the water cooling pipe 9 to the upper part of the furnace body.

Alternatively, it is possible to use a method (B) in which the header 4 provided at the bottom of the trunnion ring 2 is used to flow air from the jet port 8 into the gap between the trunnion ring 2 and the furnace body 1, or both methods. I've been exposed to it. Note that 3 is a water channel for cooling the trunnion ring, and 10 is an inspection window. However, the sixth
The conventional cooling method shown in Figures 1 to 9 has the following drawbacks.

That is, in method A: 1) If the water pipe is damaged, it cannot be repaired by replacing it because of the presence of a trunnion ring.

2) If the water piping was damaged and a large amount of water splashed onto the furnace body - there was a risk that the furnace body would receive thermal shock and cracks would occur.

3) If the water pipe is damaged and a large amount of water comes out, it will come into contact with molten steel and cause a steam explosion, which is extremely dangerous.

In addition, in method B: 1) The air flow is parallel to the furnace surface, and the cooling effect is small.

2) To solve the problem in 1) above, a very large amount of air is required, but a large diameter air supply pipe with a large pressure loss is required, and the method of holding and transferring it is necessary. It is almost impossible to supply air to the rotating parts of the furnace body.

3) Because the trunnion ring is cooled only from the bottom, as shown in Figure 9, it is not possible to cool almost uniformly over the entire area of the furnace covered by the trunnion ring, resulting in a temperature difference of approximately 150°C between the bottom and top of the trunnion ring. occurs. (The white area indicates the range of gas collision flow.) Therefore, method A is rarely used for cooling the reactor belly covered by the trunnion ring, and method B is performed simply, although incompletely. situation.

(Problems to be Solved by the Invention) The present invention was made to solve these problems, and uses gas as a cooling medium to solve problems such as cracks in the reactor body and steam explosions caused by water. In addition, by adopting a direct injection type, it provides a safe, easy-to-maintain, and simple cooling method that achieves the same or better cooling effect with a smaller amount of air than the parallel type of prior art B.

(Means for Solving the Problems) To achieve the above object, the present invention provides a method for cooling a converter abdomen covered with a trunnion ring, in which the inside of the trunnion ring is penetrated in a direction substantially perpendicular to the furnace body abdomen. A large number of replaceable nozzles are supported almost perpendicularly to the abdomen of the furnace body through a large number of sleeves and trunnion ring inspection windows. A method for cooling a converter furnace body characterized by uniformly cooling the belly of the furnace body by direct blowing.

Hereinafter, the method of the present invention will be explained in detail based on the drawings.

FIGS. 1 to 3 show an embodiment of the cooling method according to the present invention, in which a main header 4 is provided above and below the outer circumference of a trunnion ring 2, and the main headers 4 and 7 are connected via a flange 6. Integrated deaf nozzle 5 with 3 to 5 nozzles
It consists of a trunnion ring inner sleeve 7 arranged at regular intervals and penetrated through the trunnion ring.

The main header 4 supplies air, which is a cooling medium, from a supply source (not shown) to each nozzle section 5 at equal pressure, and has two stages, upper and lower, to reduce pressure loss as much as possible.

The integrated nozzle 5 extends from 3 to 3 in the height direction of the trunnion ring 2.
It has five nozzles 8'i, and air is blown out from each nozzle to the abdomen of the furnace body. The shape of the spout 8 may be a perfect circle, an ellipse, or a cylindrical or conical shape. The nozzle 5 is fixed via the main header 4 and the flange 6. A large number of these integrated nozzles 5 are arranged at regular intervals throughout the circumferential direction of the converter belly.

The inner sleeve 7 of the trunnion ring 2 is for holding the integrated nozzle, and is welded approximately horizontally to the trunnion ring portion 2 or its inspection window 10. Sleeve 7 is welded to the extra thick trunnion ring, so 30
It has a thickness greater than that of a silk. The inside of the trunnion ring 2 normally becomes a water channel 3 for cooling the trunnion ring, but since the sleeve 7 is completely welded to the trunnion ring 2, there is no danger of shallow water.

The integral nozzle 5 is held inserted into the sleeve 7, but it is fixed by the flange 6, so there is no risk of it falling off.Moreover, the nozzle part 5 can be replaced only by the flange 6.
This is easily done by simply removing the bolts.

The arrangement of the jet nozzles 8 is free, but as shown in Fig. 4, the effect is very large in the area where the air reaches within a radius of about 200 volts from the jet branch point, so the pitch is 400 to 50.
A staggered arrangement of 0 m is economical and highly effective.

Further, the diameter of the jet port 8 is about 30 to 50 cm, but when the jet flow velocity is about 20 to 30 cm, the diameter has little influence, and is determined by the total air flow rate, pressure loss, etc.

(Example) The results of applying the present invention to an actual converter are shown below.

l) Air volume 300 m'/min Pressure 2000+
Can be supplied with a*Aq low pressure blower 2) Number of jets: 132 3) Nozzle diameter: 4OA 4) Nozzle pitch: 566 or more As shown in FIG. 5, the average temperature could be reduced by about 70° C. from 450° C. in the conventional method shown in FIG. 9 to 380° C.

(Effects of the Invention) By the cooling method of the present invention, the temperature of the abdomen of the converter body can be more uniformly lowered to 400° C. or lower than in the conventional method. Generally, the strength of the converter body shell decreases at temperatures above 400°C, so the effect of preventing deformation of the converter body shell is very large. Furthermore, problems such as the number of converter repairs and falling-off of lining bricks due to this deformation can be reduced.

Furthermore, since air is used as a cooling medium, it is safe even if the cooling device is damaged, and has great effects such as easy replacement and ease of maintenance.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram of the entire cooling device of the present invention, Fig. 2 is a sectional view of the cooling device of the present invention, Fig. 3 is a front view of the cooling device of the present invention, and Fig. 4 shows the cooling effect of air. A comparison diagram, FIG. 5 is a temperature distribution diagram of the converter furnace body in an example of the present invention, and FIG.
The figure is a conceptual diagram of a conventional cooling device, and Figure 7 is a cross-sectional view as well.
FIG. 8 is a front view, and FIG. 9 is a temperature distribution diagram of a conventional converter body. 1: Converter furnace body, 2: Trunnion ring, 3: Trunnion cooling channel, 4: Air header, 5-piece integrated nozzle, 6:
Flange, 7: Sleeve, 8: Spout, 9: Water cooling pipe, 10:) Runion ring inspection window. Figure 1

Claims (1)

[Claims] In a method for cooling the abdomen of a converter covered with a trunnion ring, the inside of the trunnion ring is penetrated almost perpendicularly to the abdomen of the furnace body through a number of sleeves and trunnion ring inspection windows. Cooling of a converter furnace body characterized by arranging a large number of vertically supported and replaceable nozzles, and cooling the furnace body abdomen by blowing gas directly over the entire area of the furnace body abdomen from the jet nozzle at the tip of the nozzle. Method.