CN1049714A

CN1049714A - Direct current electric arc furnace

Info

Publication number: CN1049714A
Application number: CN90107301A
Authority: CN
Inventors: 沃尔特·博奇斯勒; 安特·埃泰罗维奇; 斯文-埃纳尔·斯滕克菲斯特
Original assignee: Sweden General Electric Brown Boveri AG
Current assignee: Swiss high Keith Stan AG
Priority date: 1989-08-21
Filing date: 1990-08-21
Publication date: 1991-03-06
Also published as: EP0413970A1; RU1784089C; DE59002718D1; CA2023041A1; ZA906533B; ES2046611T3; CH678785A5; KR0172120B1; JPH0395387A; KR910005727A; JPH0762585B2; ATE94716T1; CN1019141B; EP0413970B1; BR9004099A

Abstract

In a direct current electric arc furnace, the electric conductivity furnace bottom, i.e. stove electrode (7,8,11) must be with the metal-back body phase insulation of insulating materials and cupola well.For this purpose, the base plate (11) of carrying electric conductivity furnace bottom has formed the bottom of cupola well basically.This base plate (11) is by insulating or being that the middle of non-conductor material (18) connects on the inwardly outstanding part (17) that is bearing in metal cylinder housing (2) at least.

Description

Direct current electric arc furnace

The present invention relates to a kind of direct current electric arc furnace, it comprises the cupola well of a metal shell, electrode and at least one electric conductivity furnace bottom that at least one connects as negative electrode, the bottom of stove comprises a furnace lining layer of being made up of the inserts of the brick that conducts electricity or other same functions, the furnace lining layer is bearing on the base plate, form an electric conductivity furnace bottom that connects as anode with base plate, the electric conductivity furnace bottom metal-back body phase insulation of insulating materials and cupola well.

The present invention is with prior art, and as United States Patent (USP) 4,228, No. 314 conducts are with reference to data.

In direct current electric arc furnace, electrode that connects as negative electrode and siege or hearth electrode (according to United States Patent (USP) 4,228, No. 314 make the electric conductivity furnace bottom usually) all must with the metal-back body phase insulation of cupola well.In existing electric arc furnaces, the parts that adjoin with it of electric conductivity furnace bottom and furnace bottom lining all are bearing on the metallic plate.This piece metallic plate is bearing in again on one deck insulating materials on (metal) cylinder bottom.The electrical connection of electric conductivity furnace bottom is to be realized by the contact component that passes the opening in the cylinder bottom.Because the weight of furnace charge and the excessive temperature that produces during operating period at electric arc furnaces, be very high to the requirement of described insulating barrier.Special cooling to this zone is very expensive.

The object of the present invention is to provide a kind of the sort of direct current electric arc furnace of being mentioned when beginning, its electric conductivity furnace bottom and cylinder shell are insulated rightly, and this insulation can be born whole loads that operation produces.

According to the present invention, this purpose is reached like this, and promptly described base plate constitutes cylinder bottom basically, this base plate be overlapped on the cupola well metal shell bribe in outstanding part, and by insulating materials or be at least a non-conductor material in the middle of connect supporting thereon.

Advantage of the present invention can find out that especially promptly the whole base section of electric arc furnaces is suspended in the furnace shell as floating from this respect, and the realization of this base section and furnace shell body phase insulation is very simple.

With reference to the accompanying drawings embodiments of the invention and thus obtained advantage are done more detailed description.

The embodiment of the invention in the accompanying drawing all is schematically to represent, wherein

Fig. 1 is the side view according to first embodiment of direct current electric arc furnace of the present invention;

Fig. 2 is at the supporting of the cupola well base section of another kind of type and the detailed map of insulation.

Fig. 1 shows a direct current electric arc furnace 1, and it is equipped with the housing made from metal material 2 commonly used.In an embodiment, electric arc furnaces has only an electricity level 3 that connects as negative electrode, but also can have two, three or more.In an embodiment, electrode is made hollow, this means, this stove is applicable to the purpose of reduction, but subject matter of the present invention also can be used to have the smelting furnace of the solid electrode (being generally graphite electrode) that connects as negative electrode.

Under the situation of reduction, for example, in order to produce the pig iron, concentrate, coke and lime stone are added in the stove by the centre gangway in the electrode, just can ordinary mode obtain an electrode points below electrode 3, just the melt face of a no ore deposit quarrel.As ordinary, smelting furnace has a pouring lip 5 and an aperture of door 6.In furnace bottom an electric conductivity furnace bottom is housed.The electric conductivity furnace bottom is made up of the interior brick 8 that metallic conductor 7 is housed.Conductor 7 penetrates a furnace bottom lining 10 that is positioned at below it, and this lining for example is made up of the carbon brick of conduction.Ordinary stove bricking 9 links to each other with the external world.The brick of furnace bottom lining is arranged in one or more layers and is placed on the base plate 11 of a hemisphere face shape.This base plate 11 stretches very wide and constitutes furnace bottom.It is by steel or copper one-tenth and is connected on the anode of dc source 12.The electric conductivity furnace bottom need have very big extending range, the smelting furnace electric current can be distributed on most of area of bottom, thereby avoid the tilting of electric arc 13 basically.Dispose cooling device 14 on the base plate 11 so that make it keep alap temperature, the unlikely damage that is subjected to heat in the stove.The 16th, the suction outlet of waste gas.

The brick 8 that is configured in conductor 7 is as the usefulness of the Ampereconductors between furnace charge 15 and the electric conductivity furnace bottom be made up of outer lining 10 and base plate 11, and this electric conductivity furnace bottom can certainly have different structures.Therefore except with the carbon brick, other the member that can keep electrically contacting also can be used.

With regard to this respect, this direct current electric arc furnace is equivalent to prior art, as in No. 3,022,566, No. 4,228,314, the United States Patent (USP) mentioned in beginning and the DRP detailed description is arranged all.

According to the present invention, the housing 2 of cupola well be radially inwardly crowd around and form an inwardly outstanding collar 17.Base plate 11 radial overlaps are on the collar 17.In the zone of overlap joint, disposed the ring 18 of an insulating materials.The whole base section of smelting furnace just is bearing on the collar 17 by this way.The base section of smelting furnace resembles and swims in the cupola well 1.At the same time, between smelting furnace housing 2 and the base plate 11 and by and the electric conductivity furnace bottom between insulation just be achieved by insulating materials 18.

The end limit 19 that is bent upwards of the collar 17 is used for radial centering, yet this end limit 19 does not stretch upwards to base plate.Be directed into insulating materials in order to exert all one's strength, the marginal portion of base plate 11 is equipped with a compensated loop 20 that is roughly the wedge cross section clearly wash rice.

Perhaps use prefabricated components, brick of making as refractory material or grog structure are piled up from level to level with loosing or are with fire mortar that it is adhered to one another, and perhaps also available material feeding or tamping material are as insulating materials.Here main condition is that except low conductivity, insulating materials must can be stood compression.Say again, in fact also do not need real insulator.If the conductance of insulating materials is also just much of that less than the first power of the conductance at least ten of electric conductivity furnace bottom in the vertical axis of stove.

What show among Fig. 2 is the direct current electric arc furnace that has heteroid furnace shell or furnace bottom with the embodiment with the material feeding of watering or tamping material of ubi supra.

An annular slab 21 is fixed on the cylindrical shape cylinder shell 2.A pipe fitting 22 that axially stretches is welded on the inner periphery of this plate 21.The function of annular slab 21 be equivalent to Fig. 1 in the collar 17, and pipe fitting 22 is equivalent to the curved end fan 19 of the collar 17.Similar to Fig. 1, base plate 11 is equipped with a compensated loop at its fringe region, and compensated loop is designed to a Welding Structure here, and ring 20a and a pipe fitting 20b who axially stretches of a circumferentially extending are arranged.Pipe fitting 20b stretches above plate 20a downwards and is welded on the support ring 23.

In the manufacture process of smelting furnace, before the body of heater bricking is carried out, base plate 11 is inserted together with

parts

20a, 20b and 23 in advance, and it is directed and temporary fixed by the insulating cell (not shown) with respect to furnace shell 2 and plate 2.Then with a kind of material feeding or tamping material 24 of watering, refractory concrete for example pours into the space between furnace shell 2 and the pipe fitting 22 and is connected in the zone at top, this mode in fact will encircle 20a and 23 and pipe fitting 20b be embedded in this fully and water in material feeding or the tamping material.Just continue smelting furnace is built up after this by ordinary mode.

Claims

1, a kind of direct current electric arc furnace, it comprises a cupola well (1) that is centered on by metal shell (2), electricity level (3) and at least one electric conductivity furnace bottom (7 that at least one connects as negative electrode, 8,11), the bottom of stove comprises a furnace lining layer of being made up of the inserts of the brick that conducts electricity or other same functions, the furnace lining layer is bearing on the base plate (11), form an electric conductivity furnace bottom that connects as anode with base plate, the electric conductivity furnace bottom is by using insulating materials (18,24) insulate mutually with the metal shell (2) of cupola well (1), it is characterized in that wherein said base plate (11) constitutes cylinder bottom basically, base plate (11) is overlapped on the inwardly outstanding part (17 of cupola well (1) metal shell (2), 21), and by insulating materials (18,24) or be at least a kind of non-conductor material (18,24) in the middle of connect supporting thereon.

2, electric arc furnaces as claimed in claim 1 is characterized in that wherein inwardly outstanding part (17) fuses with cylinder shell (2).

3, electric arc furnaces as claimed in claim 1 is characterized in that wherein inwardly outstanding part is an annular slab (21) that is connected the housing bottom securely.

4, electric arc furnaces as claimed in claim 1 is characterized in that wherein base plate (11) is designed to be roughly the hemisphere face shape, and compensated loop of its fringe region configuration (20,20a).

5, as one of in the claim 1 to 4 described electric arc furnaces, it is characterized in that wherein insulating materials comprises independent building brick stone, particularly refractory brick or grog, these bricks or grog or scall stack to be built or together adhered to one another with fire mortar.

6, as one of in the claim 1 to 4 described electric arc furnaces, it is characterized in that wherein insulating materials is the particularly a kind of material feeding or tamping material of watering of refractory concrete of refractory material.

7, as one of in the claim 1 to 6 described electric arc furnaces, the conductance that it is characterized in that insulating materials wherein is in the vertical axis of the stove first power less than the conductance at least ten of electric conductivity furnace bottom (7,8,11).