RU2109068C1 - Tuyere for blast furnace - Google Patents

Abstract

FIELD: designs of blast-furnace tuyeres. SUBSTANCE: tuyere has water-cooled body and hollow rear chamber and head whose surfaces of heating and deformation are made of copper castings reinforced by heat screen formed of steel heat capillary tubes whose bodies intercross to serve as stiffening ribs and their branches. Stiffening ribs comprise the secondary cooling circuit distinguished by the fact that ends of stiffening ribs are deepened into walls of cooled sleeve of the head and located in row of displacement of stiffening ribs in antiphase to form bimetallic connection together with sleeve over the entire area of contact. EFFECT: higher efficiency. 2 dwg ЫЫЫ1

Description

 The invention relates to the field of ferrous metallurgy, in particular to the construction of a lance for a blast furnace.

 The tuyere for a blast furnace is one of the main units of furnaces for iron-forming processes [1]. Through it, gas and air are supplied to the blast furnace, so the walls need forced water cooling. A known lance design for a blast furnace containing an external and internal cylinder, between which there is a gap limited by the end wall. An intermediate cylinder with external and internal partitions forming a rotary channel, respectively, external and internal, is placed in the gap. The outer section of the channel from the bottom and top is connected to the inner one, their cross section decreases in the direction of injection, increasing the cooling rate of water [2]. The walls of the outer and inner cylinder operate in heat-stressed conditions, so one of the main requirements for the design of the tuyere for blast furnaces is to ensure reliable heat dissipation and protect the outer and inner walls from burnout and abrasion - a skull and smelted iron.

 A disadvantage of the known lance design for a blast furnace is the insufficient rigidity of the walls of the outer and inner cylinder, made mainly of copper or its alloys.

 The thermal and physical wear of the lance tip for the blast furnace results in the death of the tip, which leads to an accident (i.e., water escaping into the furnace) and alteration of the entire lance, since it consists of an integral external and internal cylinder.

 A known lance design with separate cooling circuits for the tip and for the housing, selected as a prototype, containing an angular housing with a hollow rear chamber and a tip. An arcuate channel is formed in the tip, formed by a brittle extractable rod around which the tip is cast. The main part of the tip is molded in the shape of a toroid, at one end of which there is an inlet filling hole, and in the other outlet. The rear chamber and the arcuate channel of the tip have an inlet and outlet for the cooling medium. The inlet of the channel is a pipe passing through the rear chamber for connection with the inlet filling hole at one end of the toroid. The inlet filling hole is made proportional to the inlet pipe to smooth the path of passage of the cooling medium through the channel of the tip [3].

 A disadvantage of the known design is the low operational stability of the lance due to the deformation of the hollow tip. The use of an inlet filling hole, made commensurate with the inlet pipe to smooth the path of the cooling medium through the channel of the tip, and therefore the thickness of the deformation wall of the tip (made of copper or bronze), do not provide the desired structural strength, since the toroidal tip is small in thickness under the pressure of thermophysical the impact of the skull and cast iron is deformed and, abrasion, often opens the cooling cavity, leading to the accident of the furnace (due to the receipt of the cooler in the hole tip tip).

 The aim of the invention is to increase the operational stability of the tuyeres for a blast furnace.

 This goal is achieved by the fact that the lance for the blast furnace contains a water-cooled housing with a hollow rear chamber and a tip, whose heating and deformation surfaces made of copper casting are reinforced with a heat shield consisting of steel heat capillary pipes formed by crossing stiffeners and their bends, and stiffeners constitute a secondary cooling circuit, since their ends are brought into the cooled zone of the tip and are located in a series of displacements of stiffeners in antiphase and form enkah tip cooled liner over the entire area of contact bimetallic compound. The obtained bimetallic billet is mechanically processed, namely, the "excess" metal (copper) is selected in order to obtain a tip sleeve with ends of stiffener ribs buried in it, forming the specified bimetallic joint over the entire contact area of the outer and inner walls of the tip, which provides the tip with high thermomechanical operational characteristics. Comparative analysis with the prototype shows that the claimed tip is characterized in that the ends of the stiffeners are buried in the walls of the cooled sleeve of the tip and are located in a series of displacements of the stiffeners in antiphase and form a bimetallic compound with it over the entire contact area.

 Thus, the claimed tuyere for a blast furnace meets the criteria of the invention of "novelty."

 Comparison of the proposed solution not only with the prototype, but also with other technical solutions in the art did not allow them to identify signs that distinguish the claimed solution from the prototype, which allows us to conclude that the criterion of "significant differences".

 In FIG. 1 shows a longitudinal section of a lance for a blast furnace; figure 2 is a cross section of the sleeve of the lance tip for the blast furnace.

 The tuyere for a blast furnace contains a hollow rear chamber 1, a tip 2, stiffeners, a sleeve of a tip 4 for passage of a cooler. The hollow rear chamber 1 has an individual supply of cooler to the sleeve of the tip 4. Stiffeners 3, consisting of heat capillary tubes, are usually steel, are deepened and reinforced according to the configuration of the surface of the tip 2 in the form of a heat shield, each end of which is in antiphase (see figure 2 ) is brought into the walls of the cooled surface of the sleeve of the tip 4. The tip 2 is made of copper or bronze casting and forms a bimetallic joint at the contact points of the heat shield from the stiffeners 3 and their taps. The deepening of the ends of the stiffening ribs 3 into the walls of the sleeve of the tip 4 is performed in antiphase along a number of stiffening ribs 3, which allows heat to be removed throughout the mass of the copper tip 2 to the cooled walls of the sleeve of the tip 4, regardless of the heat-deforming local loads along the heating surface of the tip 2, and the number of ribs stiffness 3 and their distribution on the surface of the tip 2 depends on the specific thermophysical parameters of the melting process and cooling conditions.

 The proposed tip 2 of the tuyere for blast furnaces is made, for example, by welding the frame from heat capillary pipes and by casting a molten copper into a carbon cavity. In this case, the space of the frame, consisting of stiffeners 3 and its taps, can be welded from separate jumpers and suspensions. After casting, the external suspension is mechanically removed from the cavity of the sleeve of the tip 4, and the walls of the sleeve of the tip 4 are welded to the rear chamber 1, joining the cooler supply with the cavity of the sleeve of the tip 4. The tuyere for the blast furnace works as follows.

 By installing a lance in the blast furnace wall and providing a supply of cooler, air and gas, heating and smelting of pig iron are carried out. In the process of smelting cast iron, tip 2 is heated and deformed by a skull and melted cast iron, however, due to reinforcing it with a heat shield from cooling stiffening ribs 3, nozzle 2 absorbs and removes heat, distributing throughout the mass, since the stitches of stiffening ribs 3 are displaced and are in antiphase relative to each other friend when combining stiffeners 3, which allows you to disperse thermal loads throughout the mass of the tip 2.

 Deepening the stiffening ribs into the tip and removing heat through the bimetallic connection of the walls of the sleeve sleeve allows both rigidity and reliability of the tuyeres for the blast furnace to be increased. It is known that reinforcing refractory metals of copper structures increases their strength and resistance by more than 10 times. In addition, the bimetallic connection of cooled steel stiffeners with a copper sleeve increases the thermomechanical operational properties of the walls of the nozzle sleeve, since it provides the most tight contact between the stiffener (heat capillary tubes) and the cooled walls of the nozzle sleeve. Thus, the use of the claimed invention allows to significantly (not less than 10 times) increase the operational stability of the lance for a blast furnace, as well as its thermomechanical properties.

 1. Copyright certificate N 992587, cl. C 21 B 7/16, 1983.

 2. DE, A 2904408, cl. C 21 B 7/16, 1979.

 3. US, A 4166433, cl. 122-6.6, 1979.

Claims (1)

 A lance for blast furnaces, comprising a water-cooled case with a hollow rear chamber and a tip, the sleeve of which is made of steel heat capillary tubes, formed by crossing tubes that are stiffeners and their branches, and the stiffeners comprise a secondary cooling circuit, characterized in that, with In order to increase the operational stability of the tuyeres, the ends of the stiffeners are buried in the walls of the cooled sleeve of the tip and are located in a series of displacements of the stiffeners in antiphase with the formation of bimetal connection over the entire area of contact with the sleeve.

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