Five-hole oxygen lance nozzle of converter

Abstract

The utility model relates to a five-hole oxygen lance nozzle of a converter, and belongs to the technical field of converter steelmaking in the metallurgical industry. According to the technical scheme, the spray head comprises a spray head body (1), an outer connecting pipe (2), a middle connecting pipe (3), an oxygen connecting pipe (4) and a sealing ring (5), the outer connecting pipe (2), the middle connecting pipe (3) and the oxygen connecting pipe (4) are concentrically arranged, outer threads matched with inner threads on the inner wall of a gun body are arranged on the outer wall of the middle connecting pipe (3) and the outer wall of the oxygen connecting pipe (4), the spray head body (1) is composed of four side holes (6-2) and a center spray hole (6-1), the four side holes (6-2) are distributed in the circumference, and the center spray hole (6-1) is communicated with the center spray hole (6-1). The four side holes (6-2) are distributed in a radial mode, the included angle between every two adjacent side holes (6-2) is 90 degrees, and the center spray hole (6-1) is located in the center of the four side holes (6-2). The oxygen lance has the advantages that the oxygen enrichment capacity of a steel slag interface can be improved, slagging is promoted, the smelting time is shortened, and the service life of the oxygen lance is prolonged.

Description

Technical Field

[0001] This utility model relates to a five-hole oxygen lance nozzle for a converter, belonging to the field of converter steelmaking technology in the metallurgical industry. Background Technology

[0002] Converter steelmaking is a common steel production method, in which oxygen lances are widely used for oxygen injection. The design of the oxygen lance nozzle is crucial to the steelmaking process, and its structural characteristics directly affect the smelting effect and blowing time, thus impacting the quality and yield of the steel.

[0003] The effect of the oxygen lance on the blowing process is achieved through the interaction between the oxygen jet stream and the molten pool. This effect primarily depends on the velocity and distribution of the jet upon reaching the molten pool surface. Therefore, optimizing the various process parameters and structural design of the oxygen lance nozzle is crucial. The nozzle structure is designed based on the required oxygen velocity and flow direction. With a constant oxygen mains pressure, parameters such as the nozzle's throat diameter, outlet diameter, and expansion section determine the oxygen velocity and direction at the nozzle outlet. As the number of furnaces using the nozzle increases, the nozzle orifice diameter gradually increases due to oxygen jet scouring and molten pool erosion, resulting in an enlarged orifice. This causes the oxygen jet velocity and direction at the nozzle outlet to deviate from the initial design, adversely affecting converter smelting, such as prolonged oxygen blowing time and difficulty in controlling slag formation.

[0004] In summary, this patent designs a novel five-hole oxygen lance nozzle. Utility Model Content

[0005] The purpose of this invention is to provide a five-hole oxygen lance nozzle for a converter, which can increase the oxygen enrichment capacity of the steel-slag interface, promote slag formation, reduce smelting time, improve oxygen lance life, and solve the problems existing in the background technology.

[0006] The technical solution of this utility model is:

[0007] A converter five-hole oxygen lance nozzle includes a nozzle body, an outer pipe, a middle pipe, an oxygen pipe, and a sealing ring. The outer pipe, middle pipe, and oxygen pipe are arranged concentrically, and the outer walls of the middle pipe and oxygen pipe are provided with external threads that match the internal threads on the inner wall of the nozzle body. The nozzle body consists of four side holes and a central nozzle. The four side holes are distributed on the circumference in a radial pattern, and the included angle between two adjacent side holes is 90°. The central nozzle is located at the center of the four side holes.

[0008] The four side holes and one central nozzle of the nozzle body all adopt a Laval structure, which includes a converging section, a throat section, an expanding section and an outlet straight section connected in sequence. Its inner diameter gradually decreases from the converging section to the outlet straight section and then gradually increases.

[0009] The ratio between the diameter d of the four side holes and the diameter D of the nozzle body should be greater than or equal to 0.2 and less than or equal to 0.5.

[0010] The arrangement of the four side holes and the center injection hole forms a retracted circular injection hole area, and the angle of the retracted circular injection hole area should be greater than or equal to 20° and less than or equal to 40°.

[0011] The injection hole depths of the four side holes and the center injection hole are h1 and h2 respectively, h1 is greater than or equal to 0.8h2 and less than or equal to 1.2h2.

[0012] The beneficial effects of the present application are as follows:

[0013] (1) The present application optimizes the expansion angle by reasonably designing the oxygen injection hole layout, so that the newly designed oxygen lance has a larger oxygen flow, which can satisfy the full coverage of the top blowing oxygen on the molten iron liquid surface during the top and bottom combined blowing process of the converter, and can make the main flow of the molten iron in the converter consist of horizontal rotational flow and vertical circulating flow, thereby accelerating the reaction.

[0014] (2) The center injection hole of the oxygen lance nozzle can inhibit the generation of negative pressure area directly below the oxygen lance, reduce the "eating nose" phenomenon, and increase the oxygen enrichment capacity of the steel slag interface by matching the appropriate lance position, thereby promoting slagging from another aspect.

[0015] (3) The oxygen supply capacity of the five-hole oxygen lance of the present application is increased from 25380Nm3 / h to 29000Nm3 / h, which can shorten the blowing time by about 1.5min, increase the annual production by 150,000 tons, and the annual benefit is 75 million yuan. At the same time, the oxygen lance can significantly reduce the slag sticking, reduce the frequency of replacing the oxygen lance, and improve the service life of the oxygen lance. BRIEF DESCRIPTION OF DRAWINGS

[0016] Fig. 1 is a sectional view of the present application;

[0017] Fig. 2 is a front view of the lance head of the present application;

[0018] Fig. 3 is a sectional view of the injection hole of the present application;

[0019] In the figure: nozzle body 1, external pipe 2, middle pipe 3, oxygen pipe 4, sealing ring 5, center injection hole 6-1, injection side hole 6-2, contraction section 6-3, throat section 6-4, expansion section 6-5, outlet straight section 6-6. DETAILED DESCRIPTION

[0020] The present application will be further described by examples in combination with the drawings.

[0021] Referring to the accompanying Figs. 1-3A converter five-hole oxygen lance nozzle, comprising a nozzle body 1, an external connecting pipe 2, a middle connecting pipe 3, an oxygen connecting pipe 4 and a sealing ring 5, the external connecting pipe 2, the middle connecting pipe 3 and the oxygen connecting pipe 4 are concentrically arranged, and the outer wall of the middle connecting pipe 3 and the oxygen connecting pipe 4 is provided with external threads matched with internal threads on the inner wall of the lance body, the nozzle body 1 is composed of four side holes 6-2 and a center jet hole 6-1, the four side holes 6-2 are distributed on the circumference and distributed in a radial manner, the included angle between adjacent two side holes 6-2 is 90°, and the center jet hole 6-1 is located at the center position of the four side holes 6-2.

[0022] In this embodiment, reference is made to the accompanying drawings Figs. 1-3 The material of the oxygen lance nozzle is TU1 oxygen-free copper, the purity is 99.97%, and the oxygen content is ≤0.002%, which comprises a nozzle body 1, an external connecting pipe 2, a middle connecting pipe 3, an oxygen connecting pipe 4 and a sealing ring 5, the external connecting pipe 2, the middle connecting pipe 3 and the oxygen connecting pipe 4 are concentrically arranged, and the outer wall of the middle connecting pipe 3 and the oxygen connecting pipe 4 is provided with external threads matched with internal threads on the inner wall of the lance body, and the lance body is connected with the oxygen lance lance body. Among them:

[0023] The jet hole of the nozzle body 1 is composed of four side holes 6-2 and a center jet hole 6-1, wherein the four side holes 6-2 are distributed on the circumference and distributed in a radial manner, the center jet hole 6-1 is located at the center position of the side hole 6-2, the included angle between adjacent two side holes 6-2 is 90°, and the included angle between the axis of the center jet hole 6-1 and the axis of the side oxygen jet hole 6-2 is α 12°.

[0024] The diameter of the nozzle body 1 is D, wherein the diameter of the four side holes 6-2 is d, the diameter of the center jet hole 6-1 is D-d, and the ratio between d and D satisfies 0.2≤d / D≤0.5. The arrangement of the four side holes 6-2 and the center jet hole 6-1 forms an inwardly recessed circular jet hole area, and the angle formed by the inwardly recessed circular jet hole area is b, which satisfies 20°≤b≤40°.

[0025] The jet hole depth of the four side holes 6-2 and the center jet hole 6-1 is h1 and h2 respectively, which satisfies 0.8h2≤h1≤1.2h2.

[0026] The jet hole of the nozzle body 1 adopts Laval structure design, which includes a converging section 6-3, a throat section 6-4, an expanding section 6-5 and an outlet straight section 6-6 connected in sequence, the diameter of the outlet straight section 6-6 is 34.2mm, the diameter of the throat 6-4 is 28mm, the diameter of the four hole outlet straight section 6-6 is 52.5±0.05mm, the diameter of the throat 6-4 is 39.6±0.05mm, the expansion angle is 12°, the inner diameter of the jet hole decreases first and then increases from the converging section 6-3 to the outlet straight section 6-6, and under the condition that the oxygen manifold pressure is certain, the oxygen flow can be jetted out at a high flow rate. Example 1

[0027] The present embodiment is a 120t converter, the oxygen lance outer diameter is 273mm; the material of the oxygen lance nozzle is TU1 oxygen-free copper, purity: 99.97%, oxygen content: ≤0.002%, the nozzle is provided with five Laval nozzles, the included angle between the nozzle center line and the nozzle center line is 12°, the Mach number is 2.03, the throat section 6-4 diameter is 39.62mm, the outlet straight section 6-6 diameter is 52.50mm, the outlet straight section 6-6 length is 105mm, and the nozzle service life is 462 heats. Example 2

[0028] The present embodiment is a 120t converter, the oxygen lance outer diameter is 273mm; the material of the oxygen lance nozzle is TU1 oxygen-free copper, purity: 99.97%, oxygen content: ≤0.002%, the nozzle is provided with five Laval nozzles, the included angle between the nozzle center line and the nozzle center line is 12°, the Mach number is 2.03, the throat section 6-4 diameter is 39.6mm, the outlet straight section 6-6 diameter is 52.52mm, the outlet straight section 6-6 length is 105mm, and the nozzle service life is 481 heats.

Claims

1. A converter five-hole oxygen lance nozzle, comprising a nozzle body (1), an outer connecting pipe (2), a middle connecting pipe (3), an oxygen connecting pipe (4) and a sealing ring (5), the outer connecting pipe (2), the middle connecting pipe (3) and the oxygen connecting pipe (4) are concentrically arranged, and the outer wall of the middle connecting pipe (3) and the oxygen connecting pipe (4) is provided with external threads matched with internal threads on the inner wall of the lance body, characterized in that: The spray head body (1) is composed of four side holes (6-2) and a center spray hole (6-1), the four side holes (6-2) are distributed on the circumference and distributed in a radial manner, the included angle between two adjacent side holes (6-2) is 90°, and the center spray hole (6-1) is located at the center position of the four side holes (6-2). ​ 2. A five-hole lance nozzle for a converter as claimed in claim 1, characterized in that: The four side holes (6-2) and the center spray hole (6-1) of the spray head body (1) are all in the Laval structure, comprising a converging section (6-3), a throat section (6-4), a diverging section (6-5) and an outlet straight section (6-6) connected in sequence, and the inner diameter gradually decreases from the converging section (6-3) to the outlet straight section (6-6) and then gradually increases.

3. A five-hole lance nozzle for a converter as claimed in claim 1, characterized in that: The diameter of the spray head body (1) is D, the diameter of the four side holes (6-2) is d, and the ratio between d and D should be greater than or equal to 0.2 and less than or equal to 0.

5.

4. A five-hole lance nozzle for a converter as claimed in claim 1, characterized in that: The arrangement of the four side holes (6-2) and the center spray hole (6-1) forms an inwardly recessed circular spray hole area, and the angle formed by the inwardly recessed circular spray hole area should be greater than or equal to 20° and less than or equal to 40°.

5. A five-hole lance nozzle for a converter as claimed in claim 1, characterized in that: The spray hole depths of the four side holes (6-2) and the center spray hole (6-1) are h1 and h2 respectively, h1 is greater than or equal to 0.8h2 and less than or equal to 1.2h2.

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