JPH06147775A - Method for partial cooling of high-temperature and large-sized steel structure - Google Patents

Abstract

PURPOSE:To execute efficiently partial cooling of a vessel-shaped high- temperature and large-sized structure such as iron-making apparatuses including a converter. CONSTITUTION:A reticulate or porous refractory substance 2 having a water- retaining property and a thickness in the range of 0.5 to 150mm is fitted directly or indirectly on the outer surface of a part to be cooled, an appropriate quantity of water is supplied thereto continuously or intermittently and cooling is effected by a sensible heat and a latent heat of the water. Even when the part to be cooled is inclined, according to this constitution, the cooling water is prevented from running in the shape of a belt and also from falling down in the form of drops even when the temperature thereof reaches a boiling point, and thus the part to be cooled is cooled down uniformly and with high efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for partially cooling a high-temperature large-scale steel structure, which is excellent in cooling effect and is suitable for partially cooling high-temperature reaction vessels of iron-making equipment such as converters and chemical industry plants. It is a thing.

[0002]

2. Description of the Related Art In general, iron-making equipment such as a converter and high-temperature reaction vessels of a chemical industry plant often have a structure in which high-temperature contents are covered with a steel plate as shown in a sectional view of the converter in FIG. . That is, the structure is such that the refractory bricks 4 are stretched over the furnace interior 5 side of the steel plate steel shell 3. The steel materials used for these have high heat resistance (high-temperature strength characteristics) because of high temperature, but they may be deformed or damaged due to temperature rise and action stress due to the contents. As one of the countermeasures, the outer surface of the device (the outer surface of the steel plate) is cooled. And, as the cooling method, (1) blast cooling in which high-pressure air is blown to the cooled portion,
(2) Water injection cooling or sprinkling cooling in which water is applied to the cooled portion, and mist cooling in which (2) and (3) are developed have been performed.

[0003]

However, the above-mentioned blast cooling, water injection or sprinkling cooling, and mist cooling as the partial cooling method for high temperature large steel structures have the following problems.

(1) Impulsive cooling: The sensible heat of air is small, and the cooling effect is small despite the large amount of air blown. (2) Water injection or sprinkling cooling: When the cooling water on the surface of the cooled part reaches the boiling point, it becomes a polka-dot, cooling efficiency decreases, and if the surface to be cooled is tilted more than horizontal, the cooling water may flow in a strip shape. , The polka dots formed by boiling will fall off, which will cause a decrease in cooling efficiency and uneven cooling. (3) Mist cooling:
The structure for generating mist and the structure for feeding mist to the cooled portion are complicated and there is a problem in maintenance.

An object of the present invention is to solve the above-mentioned problems, that is, to develop a cooling method which can prevent generation of water drops due to boiling of cooling water by a simple method and can be applied not only to a horizontal surface but also to an inclined surface.

[0006]

Means for Solving the Problems The present invention is to solve the above-mentioned problems by providing a fibrous, mesh-shaped or perforated heat-resistant substance having a water-retaining property on the outer surface of a cooled portion in an amount of 0.5 mm to 0.5 mm.
A method for partially cooling a high-temperature large-scale steel structure, which is characterized in that it is attached in a range of 150 mm thickness, an appropriate amount of water is continuously or intermittently supplied to the cooled water, and the cooled portion is cooled by sensible heat and latent heat of the water. .

[0007]

The present inventors have taken advantage of the fact that the sensible heat and latent heat of water are large, while using a simple water injection or water spraying method.
Even if the surface to be cooled is tilted more than horizontal, it is possible to avoid the flow of cooling water in a strip shape, and to avoid the water drop phenomenon caused by boiling of the cooling water on the surface to be cooled or the water drops that have formed can roll from the part to be cooled. The research was repeated while adding various studies on the method of avoiding falling. As a result, if a substance having water retention property is attached to the outer surface of the cooled portion, the water supplied thereto does not flow in a strip shape even if the cooled surface is largely inclined from the horizontal, and the cooling water has a boiling point. Even if it reaches, it is difficult to form a polka dot shape, and it is possible to avoid rolling down from the surface to be cooled, and it has been found that the portion to be cooled is cooled uniformly and with high efficiency. That is, as shown in the sectional view of FIG. 1, a heat-resistant substance 2 having water retention property is attached to an outer surface 1a of a steel plate 1 which is a portion to be cooled, and water is supplied to this by means such as sprinkling 7 by a water supply device 6.

The details of the present invention will be described below. In the present invention, the water-resistant heat-resistant substance attached to the outer surface of the cooled portion refers to a substance such as metal, ceramics or carbon fiber which does not deteriorate and deteriorate even when exposed to a high temperature of about 100 to 700 ° C. for a long time. The term "fibrous", "meshed" or "perforated" is used for the purpose of imparting water-retaining property to these materials. For example, steel wool, wire mesh, porous metal, carbon fiber woven fabric, porous ceramics and the like belong to these.

The method of attachment to the cooled portion may be direct or indirect. That is, direct means a method of directly attaching to the surface to be cooled by winding, binding, joining, crimping, etc., and indirectly means a method of attaching via a material with good thermal conductivity, such as a method of attaching via a copper plate, etc. Refers to.

Regarding the thickness of the heat-resistant substance, when the heat-resistant substance is thin, the water retention is poor, and when it is thick, the cooling water gathers in the part away from the cooling surface, and the cooling efficiency is significantly reduced. The thickness of the heat resistant material is preferably 5 mm to 50 mm
However, the lower limit was set to 0.5 mm where the water retention was extremely poor, and the upper limit was set to 150 mm where the cooling efficiency was extremely lowered.

Further, the water supply method may be a method utilizing water injection, water sprinkling or capillary action. The water supply amount varies depending on the temperature, area, etc. of the portion to be cooled and is continuous or intermittent depending on the evaporation amount. You can supply water to.

[0012]

EXAMPLE As shown in the schematic view of the experimental apparatus in FIG. 3, a horizontal electric resistance type heating furnace 8 (60K) with a side furnace lid opened
W) is installed vertically on the front surface of the opening 9 at a distance of 175 mm from the opening and has a thickness of 80 mm, a height of 750 mm, and a width of 75.
The cooling effect of the steel plate was measured by attaching a thermocouple to a 0 mm steel plate 1 in a hole drilled from the furnace side and measuring the temperature thereof.

FIG. 4 is a sectional view of the steel plate 1 showing the measuring method. The thermocouple 10 was attached to the steel plate center line 1c. The thermocouple 10a is for controlling the temperature of the steel plate and is 30 mm from the steel plate.
In the position. The thermocouple 10b is located within 2 mm from the surface of the steel plate on the side opposite to the furnace. Thermocouple 10c is the same 30m
m and the thermocouple 10d are at the same 60 mm position.

[0014]

[Table 1]

Table 1 shows the thermocouple 10 using the above experimental apparatus.
After controlling the temperature of a to 800 ° C., while keeping the output power of the furnace constant, various cooling methods and the steel sheet temperature after 30 minutes when using the cooling method were measured by thermocouples 10b, 1
It is the result measured by 0c and 10d. In the table, the temperature of a, the temperature of b, etc. show the temperature of the thermocouples 10a, 10b, etc., respectively. Experiments were carried out by combining various heat-resistant substances 2 having water-holding properties and the cooling device 11, and Table 1
As is clear from the above, the temperature of the steel sheet according to the cooling methods A, B and C of the present invention may be lower than the temperature of the steel sheet according to the conventional cooling methods D, E and F and the cooling methods G and H outside the scope of the present invention. Recognize.

[0016]

As is apparent from the above embodiments, according to the present invention, even when the object to be cooled is inclined,
Cooling water flows in a strip shape, and even when the cooling water reaches the boiling point, it becomes a polka dot and does not fall from the surface to be cooled,
The part to be cooled is cooled uniformly and with high efficiency, and the industrial effect is extremely remarkable.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a method for carrying out the present invention.

FIG. 2 Cross-sectional view of converter

FIG. 3 is a schematic diagram of an experimental device.

FIG. 4 is a sectional view showing a measuring method.

Claims (1)

[Claims] 1. A 0.5 mm to 15 mm fibrous, mesh-like or perforated heat-resistant substance having water retention property on the outer surface of a cooled portion.
A method for partially cooling a high-temperature large-scale steel structure, which is characterized in that it is attached in a range of 0 mm thickness, an appropriate amount of water is continuously or intermittently supplied thereto, and a portion to be cooled is cooled by sensible heat and latent heat of water.