Ladle bottom blowing hole layout structure and ladle

Abstract

The application discloses a ladle bottom blowing hole layout structure and a ladle, and relates to the technical field of iron and steel metallurgy, and comprises a ladle bottom, which is provided with a first bottom blowing hole and a second bottom blowing hole; wherein the distance from the first bottom blowing hole to the center of the ladle bottom is 0.66R, the distance from the second bottom blowing hole to the center of the ladle bottom is 0.61R, R is the inner circle radius of the ladle, and the included angle between the first bottom blowing hole and the second bottom blowing hole with the center of the ladle bottom as the vertex is an obtuse angle. The specific bottom blowing hole layout structure has remarkable industrial application value in eliminating stirring dead zones, protecting refractory materials, reducing refining energy consumption and improving the cleanliness of molten steel.

Description

Technical Field

[0001] This invention relates to the field of iron and steel metallurgy technology, and in particular to a bottom blowhole layout structure for a steel ladle and a steel ladle. Background Technology

[0002] Bottom blowing argon into the ladle is one of the main technical methods in LF refining. By installing permeable bricks at the bottom of the ladle, argon gas is blown into the molten steel. The stirring effect of the bubbles achieves the goals of homogenizing the temperature and composition of the molten steel, promoting the flotation and removal of inclusions, and facilitating slag-steel reaction. The layout and angle of the bottom blowing holes directly affect the stirring flow field, mixing time, desulfurization efficiency, and inclusion removal effect of the molten steel.

[0003] In existing technologies, the layout of bottom blowing holes in steel ladles is typically symmetrical or simply offset, lacking refined optimization of the mixing flow field. For example, one technical solution uses a symmetrical layout with two bottom blowing holes each 0.5R from the ladle center, at a 90° angle. While structurally simple, this results in a large dead zone during mixing, long mixing time, and low desulfurization efficiency. Another common solution uses two bottom blowing holes at 0.75R and 0.75R from the center, at a 180° angle, but this layout suffers from severe erosion of the permeable bricks near the ladle wall and rapid corrosion of the refractory material. Furthermore, existing bottom blowing hole layouts also have drawbacks such as high power and argon consumption and unsatisfactory inclusion flotation. Therefore, existing technologies still lack a steel ladle structural solution that specifies and structures the bottom blowing hole layout parameters, directly guiding ladle manufacturing and on-site construction. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a steel ladle bottom blowhole layout structure and steel ladle.

[0005] To solve the above technical problems, the technical solution of the present invention is as follows: A ladle bottom blowhole layout structure includes: The bottom of the ladle is provided with a first bottom blow hole and a second bottom blow hole; Wherein, the distance between the first bottom blowing hole and the center of the bottom circle of the ladle is 0.66R, and the distance between the second bottom blowing hole and the center of the bottom circle of the ladle is 0.61R, where R is the inner radius of the ladle; The angle between the first bottom blowing hole and the second bottom blowing hole with the center of the bottom of the ladle as the vertex is an obtuse angle.

[0006] On the other hand, the present invention also provides a ladle, including the above-described ladle bottom blowhole layout structure.

[0007] The beneficial effects of this invention are: (1) The first bottom blowing hole of the present invention is set at 0.66R and the second bottom blowing hole is set at 0.61R, so that both bottom blowing holes are precisely limited to the middle section of the bottom radius of the ladle (0.61R~0.66R). This spatial structure avoids the problem that the airflow is concentrated in the central area and the molten steel at the edge far from the center is not stirred enough due to the bottom blowing hole being too close to the center; it also avoids the problem that the bottom edge and side wall refractory material is severely eroded due to the bottom blowing hole being too close to the ladle wall (such as 0.75R in the prior art). Thus, while ensuring the effective stirring strength of the whole ladle, it significantly slows down the erosion of the refractory material and extends the service life of the ladle.

[0008] (2) This invention achieves a specific physical coupling between the two argon gas streams as they rise in the molten steel by precisely limiting the included angle of the two hole axes to 131° in an asymmetric spatial arrangement. This special asymmetric gas flow coupling mechanism drives and forms a more complete and scientifically circulated dynamic flow field inside the ladle, significantly reducing the volume of the stirring dead zone, making the temperature and composition of the molten steel in the ladle rapidly more uniform, and greatly improving the overall efficiency of the desulfurization and refining reaction.

[0009] (3) This invention, through the combination of an asymmetric angle of 131° and a fixed mid-section position of 0.61R / 0.66R, makes the energy dissipation distribution when the rising airflow reaches the surface of the molten steel more reasonable, so that the slag layer on the surface of the molten steel exhibits a uniform creeping rather than a state of violent turbulence. This effectively avoids the serious slag entrapment, exposed molten steel and secondary oxidation caused by excessive local stirring intensity. While significantly improving the cleanliness of the molten steel, it also greatly reduces the ineffective consumption of electrical energy and argon density. Attached Figure Description

[0010] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram of the bottom blowing position of the ladle before and after the modification, as shown in the embodiment. Among them: 1. Steel ladle; 2. First bottom blow hole; 3. Second bottom blow hole. Detailed Implementation

[0012] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0013] Example 1: This example was implemented on ladle #49 in the No. 1 steelmaking plant of a steel company. This ladle is ladle 1 used in the converter-LF-RH refining process, and the inner radius of the ladle is R=1500mm. Before applying the solution of this invention, the plant originally had two bottom blowing holes with distances from the center of the hole of 0.79R and 0.66R respectively, and the included angle between the two holes was 91°.

[0014] This embodiment provides a bottom-blowing hole layout structure for a ladle, which reconstructs the bottom structure of the ladle 1 at specific points. The structure includes the bottom of the ladle 1 and two bottom-blowing holes located at the bottom. By limiting the included angle of the axes of the two bottom-blowing holes to an asymmetric spatial arrangement, specific physical coupling is achieved between the two argon gas streams as they rise in the molten steel. This unique asymmetric gas flow coupling mechanism drives and forms a more complete and scientifically designed dynamic flow field within the ladle 1, significantly reducing the volume of the stirring dead zone, rapidly homogenizing the temperature and composition of the molten steel throughout the ladle, and greatly improving the overall efficiency of the desulfurization and refining reactions.

[0015] Specifically, two bottom blowing holes are formed at the bottom of the ladle 1, namely the first bottom blowing hole 2 and the second bottom blowing hole 3. The distance between the first bottom blowing hole 2 and the center of the bottom circle of the ladle 1 is 0.66R, and the distance between the second bottom blowing hole 3 and the center of the bottom circle of the ladle 1 is 0.61R. Here, R is the inner radius of the ladle 1, and R is measured with the center of the bottom of the ladle 1 as the center. The angle between the first bottom blowing hole 2 and the second bottom blowing hole 3 with the center of the bottom circle of the ladle 1 as the vertex is 131°.

[0016] The two bottom blow holes are asymmetrically arranged relative to the bottom center of ladle 1. Both the first bottom blow hole 2 and the second bottom blow hole 3 are equipped with permeable bricks, which are connected to the bottom blow pipe to introduce refining argon gas.

[0017] The experiment tracked the 49# ladle for a complete service life and compared it with other ladles of the same steel grade using the conventional original layout. During the static stirring process of LF / RH refining, the static stirring flow field of the 49# ladle was good, the slag surface was in a slight creeping state, and there was no violent churning or exposure of molten steel on the surface.

[0018] The specific experimental comparison data results are as follows: (1) Desulfurization effect: Thanks to the elimination of the stirring dead zone by the 131° asymmetric layout, the desulfurization rate of non-vacuum steel of 49# ladle 1 increased by 9.80%, the desulfurization rate of vacuum steel increased by 2.92%, and the average desulfurization rate of the whole process increased by 5.57%.

[0019] (2) Energy consumption reduction: Due to the shortening of mixing time caused by the circulating flow field, the power consumption of non-vacuum steel is reduced by 11.74%, the power consumption of vacuum steel is reduced by 4.40%, and the average power consumption is reduced by 6.80%; the energizing time of non-vacuum steel is reduced by 10.55%, the energizing time of vacuum steel is reduced by 3.38%, and the average energizing time is reduced by 6.05% accordingly.

[0020] (3) Argon consumption: After the flow field distribution was optimized, the bubble stirring efficiency was greatly improved, the argon consumption of non-vacuum steel was reduced by 9.92%, the argon consumption of vacuum steel was reduced by 3.99%, and the average argon consumption was reduced by 8.06%.

[0021] (4) Refractory erosion: Since the bottom blow hole is controlled in the middle section of 0.61R~0.66R, the erosion of the refractory on the ladle wall is slowed down. When the ladle 1 is taken off the line, the slag line brick thickness reaches 65mm (60mm for ordinary ladle 1) and the molten pool thickness reaches 90mm (85mm for ordinary ladle 1).

[0022] (5) Flaw detection and cleanliness: The optimization of the refining flow field significantly promoted the collision and flotation removal of inclusions. The flaw detection pass rate of pipeline steel reached 99.26%, and the flaw detection pass rate of non-pipeline steel reached 100%, with the overall flaw detection pass rate increasing by 0.38% compared to ordinary ladle 1. The proportion of grade 1.0 inclusions in pipeline steel reached 99.47%, an increase of 0.21% compared to ordinary ladle 1, and the pass rate of grade 1.5 and above inclusions reached 100%. Tracking the inclusion rating of pipeline steel since the commissioning of ladle 1 #49 shows that the pass rate of grade 1.5 is 99.67%, and the pass rate of grade 2.0 reaches 100%.

[0023] The data from the above embodiments fully demonstrate the significant industrial application value of the specific bottom blow hole layout structure of this application in eliminating stirring dead zones, protecting refractory materials, reducing refining energy consumption, and improving the cleanliness of molten steel.

[0024] Example 2: This example provides a steel ladle 1, which includes the bottom blowhole layout structure of the steel ladle 1 provided in Example 1. The steel ladle 1 is filled with refractory material, which includes slag line bricks laid on the side walls and a molten pool structure at the bottom.

[0025] In addition to the above embodiments, the present invention may have other implementation methods; all technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope claimed by the present invention.

Claims

1. A steel ladle bottom blowhole layout structure, characterized in that: include: The bottom of the ladle (1) is provided with a first bottom blow hole (2) and a second bottom blow hole (3); Wherein, the distance between the first bottom blowing hole (2) and the bottom center of the ladle (1) is 0.66R, and the distance between the second bottom blowing hole (3) and the bottom center of the ladle (1) is 0.61R, where R is the inner radius of the ladle (1); The angle between the first bottom blowing hole (2) and the second bottom blowing hole (3) with the bottom center of the ladle (1) as the vertex is an obtuse angle.

2. The ladle bottom blowing hole layout structure according to claim 1, characterized in that: The angle between the first bottom blow hole (2) and the second bottom blow hole (3) with the bottom center of the ladle (1) as the vertex is 131°.

3. The ladle bottom blowing hole layout structure according to claim 1, characterized in that: Both the first bottom blowing hole (2) and the second bottom blowing hole (3) are equipped with permeable bricks. The permeable bricks are connected to the bottom blowing pipeline set on the outside. The bottom blowing pipeline is used to blow argon gas into the ladle (1).

4. The ladle bottom blowing hole layout structure according to claim 1, characterized in that: The first bottom blow hole (2), the second bottom blow hole (3), and the bottom center of the ladle (1) form an asymmetrical layout structure.

5. A steel ladle, characterized in that: Includes the ladle bottom blowhole layout structure as described in any one of claims 1 to 4.

6. The steel ladle according to claim 5, characterized in that: The ladle (1) is provided with refractory material inside, which includes slag line bricks laid on the side wall and a molten pool structure set at the bottom.

7. The ladle according to claim 5, characterized in that: The inner radius R of the steel ladle (1) is 1500mm.

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