RU123128U1 - WATER-COOLED ARCH OF ARC-MELTING FURNACE - Google Patents

Abstract

1. A water-cooled roof of an arc steel-making furnace, containing a water-cooled panel formed by concentric rows of water-cooled pipes, a central refractory plate, characterized in that the inclined part of the water-cooled panel is made with a bend dividing it into the outer and inner parts, while the angle of inclination of the walls of the inner part of the water-cooled panel is 60-90 ° to ensure the removal of the central refractory plate from the metal level by 300-400 mm. 2. The roof according to claim 1, characterized in that sealing refractory rings are laid on the central refractory plate.

Description

The utility model relates to metallurgy, to the design of water-cooled arches of arc steel furnaces.

Known water-cooled arch vault steel furnace, containing a peripheral vault ring, which is used as a thick-walled pipe connected to the Central ring by many pipes located obliquely at an angle of 10-15º to the horizontal. The central ceramic part of the arch has a spherical shape and is mounted on the central ring (“Design and operation of heavy-duty arc steel-smelting furnaces” D.Ya. Povolotsky, Yu.A. Gudim, I.Yu. Zinnurov, Metallurgy Publishing House, 1990, p. 42 )

The disadvantage of this design of the arch is that in the event of failure of a separate section of the arch, it is necessary to repair the arch as a whole, in addition, it is difficult to produce a spherical arch. In the known construction, only the central part of the arch is obtained remote from the metal level.

A water-cooled arch vault of a steelmaking furnace is known, in which the central refractory plate is raised due to the refractory part in the form of a ring, and the ring, in turn, is supported by the outer surface on a water-cooled panel. When using this design, a quick replacement of the central refractory plate is possible if necessary. (US 2011243179, 10/06/2011, F27D 1/02)

The disadvantage of this development is the manufacture and fitting of two refractory segments, while the refractory part in the form of a ring is exposed to higher temperatures to a greater extent than the central refractory raised above the metal level, and the replacement of two refractory parts with a part of the water-cooled panel will be required.

The closest to the proposed utility model is the arch of the steelmaking furnace, containing a small arch in the form of a concrete refractory panel and a water-cooled panel, while the central refractory is raised above the metal level due to the fact that the whole arch is raised above the furnace with a side wall of the arch resting on the furnace flange . (US 6084902. 07/04/2000, F27D 1/02)

The disadvantage of this design of the water-cooled roof is too large an air gap between the metal and the roof of the furnace, leading to significant heat losses, which leads to an increase in the duration of smelting and increases energy costs.

The purpose of this utility model is to ensure the mechanical strength of the refractory part of the arch, increase the productivity of the arc steelmaking furnace by increasing the service life of the central refractory part of the water-cooled arch.

The technical result achieved in the claimed utility model is to increase the resistance of the refractory plate of the water-cooled arch and increase its service life.

The specified technical result is achieved in that the water-cooled arch of the steelmaking furnace, containing a water-cooled panel formed by concentric rows of water-cooled pipes, a central refractory plate, according to a utility model, the inclined part of the water-cooled panel is made with a bend that divides it into two parts - external and internal, so so that the angle of inclination of the walls of the inner part of the water-cooled panel is 60-90º, due to which the central refractory plate is removed from the metal level by 30 0-400 mm.

O-rings are laid on the central refractory plate.

From the practice of operating water-cooled arches of steelmaking arc furnaces of various capacities, it is known that the central refractory plate is a weak link in its design, since it is more susceptible to high thermal loads. In addition, 1-6 row of cooling pipes adjacent to the central refractory vault plate are subject to high loads and a higher failure rate.

The water-cooled arch is a central refractory plate, resting on its side chamfer on a structure of pipes through which coolant is passed. Usually cooling pipes are rolled into rings, the radius of each subsequent pipe is smaller than the previous one.

The technical solution proposed by this utility model consists in that the inclined part of the water-cooled panel is bent and is thereby divided into two surfaces — the outer part of the water-cooled panel and the inner part of the water-cooled panel. The round-shaped outer part of the arch panel has a support for the inner part of the panel and is formed by concentric rows of cooling pipes extending inward from the support of the outer part of the panel to the support of the inner part. The inner part of the arch panel has a circular shape and is located within the central hole of the outer part of the arch panel and is mounted on it using brackets. The inner part of the arch panel is formed by concentric rows of cooling pipes extending upward from the support of the inner part of the panel to the support of the central refractory plate, while the angle of inclination of the walls of the inner part of the water-cooled panel is 60-90º. This allows you to raise the refractory plate above the metal bath and the burning zone of the electric arc. Due to this bending of the water-cooled panel, the central refractory plate is 300-400 mm away from the metal level. This distance is sufficient to reduce the heat load on the central refractory plate and increase its service life. The central refractory plate may further comprise water cooling of the external facet and has openings for vaulted graphite electrodes.

As the refractory part of the arch becomes worn out, electrode gaps increase, which leads to a significant increase in the number of fugitive dust and gas emissions from the working space. The proposed design provides an additional seal in the form of refractory rings, which are laid on the central refractory plate. They prevent unorganized pyleunos and extend the life of the central part of the arch. The sealing refractory rings are laid so that the axis of symmetry coincides with the axis of the holes for the graphite electrodes on the central refractory.

The central refractory slab is usually made of heat-resistant concrete and may have a round or deltoid shape. The refractory center plate rests on the inside of the water-cooled panel, which is a water-cooled tubular structure that allows quick replacement of the refractory center plate.

The utility model is illustrated by drawings, where

figure 1 shows a side view of the water-cooled arch of the steelmaking furnace in section;

figure 2 shows a top view of the water-cooled arch of the steelmaking furnace;

figure 3 shows a cross section of the inner part of the described water-cooled arch of the steelmaking furnace, with a partial section to illustrate the inside of the arch.

The central refractory plate 1 has three holes for the electrodes 5 and is supported by its side chamfers on the inside of the water-cooled panel 2 of the arch. Each inner ring of the arch pipes is positioned higher than the outer, so that the panels are inclined. The inclination of the walls of the inner part of the water-cooled panel of the arch 2 according to the proposed utility model is 60-90º, preferably 75 ± 5ºC. Under such a slope, 5-6 rows of water-cooled pipes are located. The inner part of the water-cooled panel on the brackets 3 is fastened to the outer part of the water-cooled panel 4. A refractory central plate 1 is installed in the inner part of the water-cooled panel. O-rings 6 are laid on the central refractory plate, coaxially with holes for graphite electrodes.

Reducing the thermal load on the central refractory stove occurs due to the removal of the stove from the metal level by 300-400 mm and, most importantly, the distance from the arc burning point. This is solved by performing a bend on a water-cooled panel and leads to insignificant heat losses, since the air gap between the metal and the furnace roof increases only in part of the roof, in the area of graphite electrodes. The use of a water-cooled arch of the steelmaking furnace according to the claimed utility model provides it with high durability, an increase in its service life and reduces the cost of steelmaking in electric arc steelmaking furnaces.

Claims (2)

1. A water-cooled arch of a steelmaking furnace, comprising a water-cooled panel formed by concentric rows of water-cooled pipes, a central refractory plate, characterized in that the inclined part of the water-cooled panel is made with a bend that divides it into the outer and inner parts, while the angle of inclination of the walls of the inner part of the water-cooled the panel is 60-90 ° to ensure the removal of the central refractory plate from the metal level by 300-400 mm. 2. Code according to claim 1, characterized in that the sealing refractory rings are laid on the central refractory plate.