SU866388A2 - Electric arc furnace bath - Google Patents

Description

The invention relates to furnace construction, specifically to furnaces for the production of slag melts, can be used in ferrous metallurgy, for example, in the design of arc slag melting electric furnaces for smelting synthetic slags used for steel refining. According to the main author. St. No. 737756 is a well-known bath of an electric arc furnace containing a casing and a lining, the bottom and the slopes of which are made of central and peripheral carbon-containing blocks separated from the casing by backfill (padding). The lining walls are made with water-cooled elements. Peripheral carbon-containing blocks of the bottom and slopes are graphitized and their height is 1.3-2.0 heights of the blocks of the bottom, and the filling is made of a material with a thermal conductivity coefficient of 0.05-0.5 of the thermal conductivity of graphite blocks. The possibility of performing peripheral graphitized blocks of the bottom and slopes with composite components in a horizontal plane with the alignment level of the docking below the upper level of the blocks of the central part of the bottom was examined by an amount equal to 0.2-0.5 of the height of the central blocks. 1. Water-cooled elements of the walls are assembled from vertically arranged copper rectangular plates with channels for the passage of water. Water-cooled copper plates (refrigerators) are conjugated on a horizontal plane with graphitized slope blocks. The outer part of the casing of the furnace bath is made with water irrigation. Water supply for irrigation is carried out below the level of conjugation of water-cooled copper plates (refrigerators) with graded blocks of slopes Q. The heat removal from graphitized blocks of slopes of the proposed bath is carried out by a gyro-electric furnace as an irrigation system through the high-T: water flow (filling), g copper stove cooler according to;: the intensity of their match.

However, performing a pairing of refrigerators and blocks of slopes only in the horizontal plane does not always ensure reliable contact between the copper and the grater and graphitic Q.

bath block slope, which leads to disruption of heat transfer, corroded in place of the connector graphitized slope block molten slag and furnace exit. The furnace irrigation system, with water supply below the level of water-cooling of copper plate refrigerators and graded blocks of slopes, cannot prevent (due to low heat removal from the molten slag penetration zone) dissolution of the bedding (packing) in it and promote slag crystallization. The process of penetration of the molten slag continues until its emergency exit from the furnace.

The purpose of the invention is to improve the heat exchange between the cooled elements of the electric arc furnace bath and graphitized slope blocks, their strength, the increase in the service life of the furnace bath, and its performance.

The goal is achieved by the fact that the mating of copper plate hoses 1odil - :: sows with graphitized slope blocks is made in the form of a lock joint, and the water supply to the furnace casing is made above the horizontal plane of the junction of refrigerators and grafted slope blocks of 0.05-0 , 5 vysty plate stove. Provision is also made of locking joints of grafted blocks of slopes and copper refrigerators in the form of trapezoidal, U-shaped T and 1-different forms. When making a lock joint of a 1-shape water: 1, the inlet of the upper part of the copper cooler is discharged onto the upper part of the graphite slope block on the ve; shchinu equal to 0.01-0.5 of the height of the graphitized slope block both from the side of the furnace bath and from the side of the furnace casing.

Such a constructive solution ensures reliable heat exchange between

graphitized slope blocks with copper plate refrigerators and a system of irrigation of the furnace casing, which increases the resistance of the grafted blocks. slopes and increases the service life of the furnace.

FIG. 1 shows the proposed bath; in fig. 2 shows a trapezoidal locking joint; in fig. 4 and 5 are of the same, shape with a water-cooled inlet of the lower part of the refrigerator from the side of the bath of the furnace and from the side of the casing of the furnace, respectively, in FIG. 6 - the same, T-shaped.

The bath of an electric arc furnace contains a casing 1 and lining 2, the bottom of which is made of vertically mounted to the heat-conducting material 3 bottoms 4 coal blocks 5. On the periphery, the lining of the walls and the bottom is made of graphite blocks 6 on thin joints with a total height of 1.3 -2.0 bottom height. Graphite blocks can be made either solid or split along the horizontal plane 7 below the upper level of the bottom by 0.2-0.5 of its height.

The space between the goafit blocks 7 and the casing I is filled with - a carbon-containing backfill (pad) 8 with a thermal conductivity coefficient of 0.5-0.05 thermal conductivity of grafted blocks. On top of the graphitized blocks are installed around the entire perimeter of the bathtub, water, air 4, Ie elements (refrigerators) 9, made of copper plates with drilled channels for the passage of water. The junction of the lower part of the refrigerators and the upper part of the graphed blocks of slopes is made in the form of a lock connection of trapezoidal (Fig. 2), U-shaped (Fig. 3), 1, and T-shaped (Fig. 4.5 and 6) forms. When making a 1-shaped locking connection, the water-cooled inlet O of the refrigerator 9 can be carried out both from the side of the furnace bath (Fig. 4) and from the side of the furnace casing (Fig. 5).

Claims (6)

The space between the refrigerator and the casing is filled with carbon gasket P. The upper part of the walls 12 above the refrigerator is made of refractory bricks. The bath casing consists of walls 13, a set of vertical bams; in fig. 3 - the same U-shaped forlock 4, welded to the wall, and at least one horizontal band 15, covering the casing, with holes 16, mating with the casing. A part of the casing above the horizontal plane 17 of the interface between the coolers and slope blocks is irrigated with water using a mounted collector casing 18 with sprinklers 19 On the bottom 4 of the casing there is a drain trough 20 for collecting water. In addition, a box 21 of beams 22 for air cooling is made on the bottom of the casing. In the upper part of the casing there is a sandbox 23 for hermetic installation on the casing of the roof. The bath also has a slag entrance 24, a metal entrance 25 and a working window 26 for loading the charge. The coal and graphitized blocks are covered with a layer of protective coal gasket 27, and the coolers outside are heated with a layer of refractories 28 for the period of preheating and start-up of the furnace. on the one hand, both by refrigerators and irrigated casing, on the other hand, and prevents the molten slag from entering this lock connection and the emergency exit of slag from the furnace. The use of the invention will significantly increase the service life of graphite blocks, extend the working campaign of the furnace, reduce the cost of operation and maintenance of the furnace, increase its productivity, which will provide economic benefits. Claims 1. Bath electric arc furnace according to ed. St. No. 737756, characterized in that, in order to improve heat exchange between the cooling elements of the electric arc furnace bath and graphite slope blocks, increase their durability, increase the service life of the furnace bath and increase its performance, conjugation of copper plate refrigerators with graphite slope blocks made in the form of a lock joint, and the water supply to the irrigation of the furnace casing is made above the horizontal plane of the interface between refrigerators and graphitized blocks of slopes by a value of 0.05-0.5 of height itovogo refrigerator. 2. The bath of claim 1, distinguished by the fact that the locking connection of the graphitized slope block and copper plate refrigerators is trapezoidal. 3. Early according to claim 1, characterized in that the lock connection of the graphitized slope block and the copper slab cooler is made U-shaped graphite block slope. 4. Bathtub according to claim 1, characterized in that the lock connection of the graphitized slope block and the copper plate cooler is made with the water-cooled inlet of the lower part of the copper slab cooler onto the upper part of the graphite block of the slope from the side of the furnace bath by the value of 0.01 -0.5 heights of the graphitized slope block. 5. Bath for PP. 1 and 4, that is, that the T-shaped water-cooled inlet of the lower part of the copper plate cooler is made from the side of the furnace shell. 6. The bath of claim 1, wherein the lock connection is T-shaped with the interface plane of the horizontal shelf of the refrigerator with the upper end of the graphitized slope block. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 2554851/02, cl. F 27 D 1/00, 1978. ten