CN213570574U

CN213570574U - Dip pipe and vacuum tank lining structure of small-tonnage single-nozzle refining furnace

Info

Publication number: CN213570574U
Application number: CN202022319599.9U
Authority: CN
Inventors: 仇云龙; 朱卫飞; 成国光; 戴卫星
Original assignee: Zhongxing Energy Equipment Co Ltd
Current assignee: Zhongxing Energy Equipment Co Ltd
Priority date: 2020-10-20
Filing date: 2020-10-20
Publication date: 2021-06-29
Anticipated expiration: 2030-10-20

Abstract

The utility model discloses a dip pipe and vacuum tank lining structure of a small-tonnage single-nozzle refining furnace, which belongs to the technical field of ferrous metallurgy equipment, and comprises a dip pipe body, an inverted cone-shaped reducing connector and a lower vacuum tank body which are connected through a steel structure, wherein the dip pipe body comprises a built-in steel liner and a pouring body, and the bottom of the dip pipe body is provided with an oblique angle; the lower vacuum groove body comprises a steel barrel shell, a heat insulation layer, a semi-permanent layer and a working layer are sequentially arranged inwards, and a closing layer is arranged at the top of the lower vacuum groove body. The utility model has the advantages that: the structure is simple, the construction is convenient, the furnace is particularly suitable for a small-tonnage single-nozzle refining furnace, the slag discharging efficiency can be effectively improved by the oblique angle design at the bottom of the dip pipe, the binding layer at the top of the lower vacuum groove can effectively inhibit steel slag splashes from adhering to the wall of the upper vacuum groove when molten steel is blown, and the heat loss of the molten steel can be reduced.

Description

Dip pipe and vacuum tank lining structure of small-tonnage single-nozzle refining furnace

Technical Field

The utility model relates to a ferrous metallurgy technical field especially involves a dip pipe and vacuum tank lining structure of usefulness are smelted to single-nozzle refining furnace.

Background

As a novel molten steel vacuum furnace external refining device, the single-nozzle refining furnace is one of important means for producing high-quality special steel, and is also a molten steel furnace external refining device independently researched and developed by China in a small number in the field of ferrous metallurgy at present. The invention is firstly proposed by the Beijing iron and steel institute (now: Beijing university of science and technology) in 1976, and is mainly used for solving the problems of short service life of a suction nozzle of an RH refining furnace, poor circulation efficiency of small ladles and the like. With the continuous and deep research and application of the single-nozzle furnace, the refining furnace has increasingly abundant metallurgical functions and smelting advantages, such as degassing, decarburization, desulfurization, deoxidation, inclusion removal, alloying and the like as described in patent No. 201010243658.7, and particularly shows strong refining advantages in the aspect of smelting ultra-low sulfur steel and ultra-low carbon steel.

The furnace body structure of the single-nozzle refining furnace mainly comprises a dip pipe and a vacuum tank, wherein the vacuum tank is generally divided into an upper tank and a lower tank, and the dip pipe is connected below the lower tank. In the vacuum treatment process, the immersion pipe and the lower vacuum tank can be in direct contact with molten steel, the working environment is the worst, and compared with the upper vacuum tank, the replacement and repair frequency of the refractory is higher. The replacement and repair frequency of the vacuum tank and the dip pipe is reduced as much as possible, and the operation rate of the vacuum refining furnace can be effectively improved. For a single-nozzle refining furnace with the weight of less than 80 tons, the inner diameter of an immersion pipe is usually less than 1m, the internal space is narrow, and the building difficulty of refractory bricks is high.

The dip tube is a refining operation before vacuum treatment, and in order to avoid the ladle slag entering a vacuum chamber to reduce the degassing and decarburization efficiency of molten steel, the dip tube is usually used for deslagging before vacuum pumping. The slag discharging process is mainly divided into two steps, wherein in the first step, before the dip pipe is immersed into molten steel, the ladle slag surface is blown away as far as possible by large-flow argon blowing, and then the dip pipe is inserted rapidly, so that most ladle slag can be discharged out of the dip pipe; and secondly, keeping the shallow insertion depth of the dip pipe, continuously blowing argon at a large flow rate, and completely discharging residual slag liquid in the dip pipe. Patent No. 201110262864.7 discloses a method for discharging slag from a dip tube, and the operation of discharging slag is described in more detail. In the practical process, the traditional slag discharging mode has some defects, particularly on a small-capacity steel ladle; the diameter of the dip pipe is in a positive correlation change relationship with the corresponding ladle capacity, but the thickness of the dip pipe wall changes less with the ladle capacity. The volume and area occupied by the dip pipe in the steel ladle are larger along with the reduction of the capacity of the steel ladle, and meanwhile, the exposed area of the slag surface blown away by argon is smaller, so that the residual slag liquid amount in the dip pipe is increased when the dip pipe is inserted, the subsequent slag discharging time is increased, and the smelting time is increased to a certain extent.

Vacuum oxygen blowing decarburization is an important metallurgical function of a single-nozzle furnace, and when molten steel is blown, high-speed oxygen jet flow impacts the steel liquid surface of a vacuum chamber to generate a large amount of molten steel splashing; when stainless steel is blown, a large amount of chromium-containing slag drops are contained in splashes, and the steel slag splashes are easily adhered to the inner wall of the upper vacuum groove, are adhered to nodules and are even pumped into a vacuum pipeline, so that the cleaning and maintenance frequency is increased, and the operation rate is reduced.

SUMMERY OF THE UTILITY MODEL

The problem of reaction in the practice more than, the utility model aims at providing a be suitable for dip pipe and vacuum tank inner lining structure that small-tonnage single-nozzle refining furnace used to through reasonable structure and material design, improve the sediment efficiency of dip pipe, reduce the building degree of difficulty of vacuum tank and dip pipe, reduce the adhesion of splash to upper portion vacuum tank, vacuum line, the cycle is repaiied in the extension groove, makes the production efficiency of single-nozzle refining furnace obtain further promotion.

In order to achieve the above purpose, the utility model provides a following technical scheme: a dip pipe and vacuum tank lining structure for a small-tonnage single-mouth refining furnace comprises a dip pipe body, an inverted cone-shaped reducing connector and a lower vacuum tank body which are connected through a steel structure; the dip pipe body comprises a built-in steel liner, casting bodies are arranged on the inner side and the outer side of the steel liner and are integrally cast and molded by corundum casting materials, the molding height of the inner casting body extends to the top of the inverted cone-shaped reducing connector, and an oblique angle is arranged at the bottom of the dip pipe body; the vacuum tank body of lower part includes the steel drum shell, inwards is equipped with heat insulation layer, semi-permanent layer, working layer in proper order, vacuum tank body internal diameter D2 of lower part is greater than dip pipe body internal diameter D1, the top of vacuum tank body of lower part is equipped with the binding off layer.

Furthermore, anchor pieces are uniformly arranged on the steel container, one end, far away from the steel container, of each anchor piece is of a forked structure, and the steel container is connected with the pouring body in an embedded mode through the anchor pieces.

Furthermore, the bottom end face of the dip pipe body is of a slope and plane structure, an acute angle alpha formed by the slope and the plane is controlled to be 10-30 degrees, and the ratio L1/L2 of the width of the slope 8 to the thickness of the dip pipe body is controlled to be 0.50-0.75.

Furthermore, the heat insulation layer is made of high-temperature ceramic fibers, the semi-permanent layer is made of corundum castable, the casting width is larger than or equal to 4cm, the working layer is formed by building any one of wedge-shaped or annular refractory bricks made of magnesium-chromium, magnesium-spinel and corundum, and the width is larger than or equal to 180 mm.

Further, the ratio D2/D1 of the lower vacuum tank body inner diameter D2 to the dip pipe body inner diameter D1 satisfies (1.1-1.5)/1.

Furthermore, the closing layer is an integral annular refractory brick, the inner diameter of the closing layer is gradually reduced from bottom to top, and the ratio D3/D1 of the diameter D3 of the contraction opening to the inner diameter D1 of the dip pipe body meets (0.9-1.1)/1.

Compared with the prior art, the beneficial effects of the utility model reside in that:

(1) the liner has a simple structure and is easy to repair, and the dip pipe body is integrally cast and molded by adopting a corundum castable, so that the liner has the advantages of high thermal stability, high structural strength, molten steel scouring resistance and good overall airtightness;

(2) the oblique angle design at the bottom of the dip pipe body can effectively improve the slag discharge efficiency;

(3) the top of the lower vacuum groove body is provided with a closing layer, so that splashes generated by converting can be effectively shielded, and the heat loss of molten steel can be reduced to a certain degree.

Drawings

FIG. 1 is a schematic diagram of the three-dimensional structure of the liner of the dip tube and the vacuum tank of the present invention;

FIG. 2 is a schematic diagram of the two-dimensional structure of the liner of the dip tube and the vacuum tank of the present invention;

FIG. 3 is a schematic diagram of the utility model of the dip pipe for discharging slag;

fig. 4 is a schematic view of the vacuum tank blowing of the present invention.

In the figure: 1-dipping a pipe body; 2-an inverted cone-shaped reducing connector; 3-lower vacuum tank body; 4-casting the body; 5-a steel liner; 6-an anchor member; 7-horizontal plane; 8-inclined plane; 9-steel drum shell; 10-a heat insulating layer; 11-a semi-permanent layer; 12-a working layer; 13-a closing layer; 14-molten steel; 15-blowing argon; 16-a ladle; 17-ladle slag; 18-conventional dip tube end face; 19-oxygen lance; 20-jet of oxygen; 21-steel slag spatter; 22-radiant heat; 23-upper vacuum tank; 24-oxygen reflexes.

Detailed Description

In order to make the technical problems to be solved, the technical features and advantages of the present invention clearer, the following will explain in detail the embodiments of the present invention with reference to the accompanying drawings.

The utility model provides a dip pipe and vacuum tank lining structure of small-tonnage single-nozzle refining furnace, as shown in figure 1, is connected through the steel construction by dip pipe body 1, back taper reducing connector 2 and lower part vacuum tank body 3 and constitutes.

A steel liner 5 used for supporting is arranged in the dip pipe body 1, anchoring pieces 6 are uniformly arranged on the steel liner 5, casting bodies 4 are arranged on the inner side and the outer side of the steel liner 5, the steel liner is integrally cast and molded by corundum casting materials, and the steel liner 5 and the casting bodies 4 form a fastening connector through the embedded connection of the branched structures at the end parts of the anchoring pieces 6 and the casting bodies 4; the molding height of the casting body 4 at the inner side of the steel container 5 extends to the top of the inverted cone-shaped reducing connector 2.

A heat insulating layer 10, a semi-permanent layer 11 and a working layer 12 are sequentially paved inwards on a steel drum shell 9 of the lower vacuum groove body 3; the heat insulating layer 10 is made of high-temperature ceramic fiber, the semi-permanent layer 11 is made of corundum castable, the casting width is more than or equal to 4cm, the working layer 12 can be built by magnesium-chromium, magnesium-spinel or corundum wedge-shaped refractory bricks or annular refractory bricks, and the building width is more than or equal to 180 mm; the ratio D2/D1 between the inner diameter D2 of the lower vacuum tank body 3 and the inner diameter D1 of the dip pipe body 1 meets (1.1-1.5)/1; the top of the lower vacuum groove body 3 is provided with a closing-in layer 13, the closing-in layer 13 is an integral annular refractory brick, the inner diameter is gradually reduced from bottom to top, and the diameter D3 of a contraction opening meets the requirement that D3/D1 is (0.9-1.1)/1.

As shown in fig. 2, the bottom of the dip pipe body 1 is provided with an oblique angle, the bottom end surface of the dip pipe body consists of a horizontal plane 7 and an inclined plane 8, and an acute angle alpha formed by the inclined plane and the horizontal plane is controlled to be 10-30 degrees; the ratio L1/L2 of the width of the inclined plane 8 to the thickness of the dip pipe body 1 is controlled to be 0.50-0.75, and the arrangement of the inclined angle aims at improving the slag discharging efficiency of the dip pipe. As shown in fig. 3, before the dip pipe is inserted into the molten steel 14, the slag surface 17 in the ladle 16 needs to be blown away as quickly as possible by means of argon blowing 15, so that the molten steel is exposed as far as possible, and then the dip pipe is inserted; the bottom of the traditional dip pipe is usually a horizontal end surface 18, the slag discharging range can be regarded as a circular area with the diameter of P1, the utility model adopts the design of adding an inclined plane on the plane, and the slag discharging range can be reduced to the circular area with the diameter of P2, as shown in the figure, P2< P1; in addition, the dip pipe inserts the in-process, and the bottom terminal surface can form extrusion contact with the slag blanket unavoidably, and after traditional horizontal terminal surface extruded the slag blanket, the slag liquid had great probably to be impressed in the dip pipe, and adopt the utility model discloses an inclined plane 8 designs, can extrude the dip pipe outside with the most slag liquid of being pressed.

The design of the top closing layer 13 of the lower vacuum tank body 3 aims to inhibit the long-distance splashing of splashes in the blowing process, as shown in fig. 4, when molten steel is blown, after a high-speed oxygen jet 20 generated by a top oxygen lance 19 impacts the liquid level of the molten steel, a large amount of slag steel splashes 21 are generated, and the splashes are easy to fly into an upper vacuum tank 23 under the action of impact inertia or oxygen reflection airflow 24 and form accretion adhesion on the inner wall. The steel slag can be inhibited from splashing to the upper vacuum groove to a certain degree by arranging the closing-up layer 13, the cleaning period of the upper groove is prolonged, and the operation rate is improved. In addition, the necking layer has another advantage that the propagation of the molten steel radiant heat 22 to the upper vacuum groove can be reduced by contracting the inner cavity, and the inner cavity is indirectly insulated.

The foregoing is a preferred embodiment of the present invention, but the present invention is not limited to the above-mentioned embodiment, which is only illustrative and not restrictive, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the scope of the invention as defined by the principle and the claims of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A dip pipe and vacuum tank lining structure of a small-tonnage single-nozzle refining furnace is characterized by comprising a dip pipe body (1), an inverted cone-shaped reducing connector (2) and a lower vacuum tank body (3) which are connected through a steel structure; the dip pipe body (1) comprises a built-in steel liner (5), casting bodies (4) are arranged on the inner side and the outer side of the steel liner (5) and are integrally cast and molded by corundum casting materials, the molding height of the inner casting body (4) extends to the top of the inverted cone-shaped variable-diameter connector (2), and an oblique angle is arranged at the bottom of the casting body (4); the lower vacuum groove body (3) comprises a steel drum shell (9), a heat insulating layer (10), a semi-permanent layer (11) and a working layer (12) are inwards and sequentially arranged, the inner diameter D2 of the lower vacuum groove body (3) is larger than the inner diameter D1 of the impregnation tube body (1), and a closing layer (13) is arranged at the top of the lower vacuum groove body (3).

2. The dip pipe and vacuum tank lining structure of the small-tonnage single-mouth refining furnace according to claim 1, wherein the steel container (5) is provided with evenly arranged anchoring pieces (6), and one end of the anchoring piece (6) far away from the steel container (5) is of a bifurcated structure.

3. The dip pipe and vacuum tank lining structure of the small-tonnage single-mouth refining furnace according to claim 1, wherein the bottom end surface of the dip pipe body (1) is composed of a horizontal surface (7) and an inclined surface (8), the acute angle α formed by the inclined surface (8) and the horizontal surface (7) is controlled to be 10-30 degrees, and the ratio of the horizontal width L1 of the inclined surface (8) to the thickness L2 of the dip pipe body (1) is controlled to be 0.50-0.75.

4. The dip pipe and vacuum tank lining structure of the small-tonnage single-mouth refining furnace according to claim 1, characterized in that the heat insulation layer (10) is made of high-temperature ceramic fiber, the semipermanent layer (11) is made of corundum castable, the casting width is not less than 4cm, the working layer (12) is built by any one of wedge-shaped or annular refractory bricks made of magnesia-chrome, magnesia-spinel and corundum, and the building width is not less than 180 mm.

5. The dip pipe and vacuum tank lining structure of the small-tonnage single-mouth refining furnace of claim 1, wherein the ratio D2/D1 between the inner diameter D2 of the lower vacuum tank body (3) and the inner diameter D1 of the dip pipe body (1) satisfies (1.1-1.5)/1.

6. The dip tube and vacuum tank lining structure of the small-tonnage single-mouth refining furnace as claimed in claim 1, wherein the necking layer (13) is an integral annular refractory brick, the inner diameter is gradually reduced from bottom to top, and the ratio D3/D1 of the diameter D3 of the necking to the inner diameter D1 of the dip tube body (1) satisfies (0.9-1.1)/1.