Current stabilizer for electromagnetic stirring tundish

Abstract

The current stabilizer is provided with a bottom wall and an annular side wall, the bottom wall and the annular side wall form a current stabilizing cavity which is provided with an upward opening and used for containing molten steel, the depth of the current stabilizing cavity ranges from 215 mm to 225 mm, the outer contour of the upper end face of the current stabilizing cavity is a chamfered isosceles trapezoid, and the inner contour of the upper end face of the current stabilizing cavity is a first rounded isosceles trapezoid; the length A of the lower bottom edge of the chamfered isosceles trapezoid is 655-665 mm, the length B of the upper bottom edge of the chamfered isosceles trapezoid is 190-195 mm, and the height C of the chamfered isosceles trapezoid is 780-785 mm; an isosceles trapezoid formed by taking two waists of the chamfered isosceles trapezoid as waists is a regular isosceles trapezoid, the length D of the lower bottom edge of the regular isosceles trapezoid is 820-825mm, the length E of the upper bottom edge of the regular isosceles trapezoid is 300-305mm, and the height F of the regular isosceles trapezoid is 620-630mm; the length G of the lower bottom edge of the first rounded isosceles trapezoid is 530-540 mm, the length H of the upper bottom edge of the first rounded isosceles trapezoid is 95-105 mm, the height J of the first rounded isosceles trapezoid is 580-590 mm, and the radius r of a rounded arc is 25-35 mm. The method can effectively limit the expansion of a molten steel impact vortex area, promote the floating of inclusions in the molten steel, and reduce the scouring of the molten steel to the tundish wall when the molten steel enters the tundish.

Description

Technical Field

[0001] The utility model relates to the technical field of steelmaking equipment, and is specifically a flow stabilizer for electromagnetic stirring ladle. Background Art

[0002] In the prior art, the electromagnetic stirring tundish flow stabilizer is installed in the impact zone of the tundish to receive the molten steel from the ladle, reduce the size of the eddy current area formed by the impact of the molten steel, slow down the scouring of the molten steel on the working layer of the tundish around the impact zone, and promote the floating of inclusions in the molten steel and improve the cleanliness of the molten steel. Due to structural limitations, the flow stabilizer in the prior art cannot effectively promote the floating of inclusions in the molten steel and reduce the molten steel impact eddy current. Utility Model Content

[0003] To this end, the technical problem to be solved by the utility model is to provide a flow stabilizer for electromagnetic stirring ladle which can effectively limit the expansion of molten steel impact vortex area, promote the floating of inclusions in molten steel, and reduce the scouring of the ladle wall when molten steel enters the ladle.

[0004] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0005] A flow stabilizer for an electromagnetic stirring ladle, comprising a bottom wall and an annular side wall, wherein the bottom wall and the annular side wall form a flow stabilizing chamber with an upward opening for accommodating molten steel, wherein the depth of the flow stabilizing chamber is 215-225 mm, and the outer contour of the upper end surface is a cut-angle isosceles trapezoid, and the inner contour is a first rounded isosceles trapezoid;

[0006] The length A of the lower base of the chamfered isosceles trapezoid is 655-665mm, the length B of the upper base is 190-195mm, and the height C is 780-785mm; the isosceles trapezoid formed by the two sides of the chamfered isosceles trapezoid is a regular isosceles trapezoid, and the length D of the lower base of the regular isosceles trapezoid is 820-825mm, the length E of the upper base is 300-305mm, and the height F is 620-630mm;

[0007] The lower base length G of the first rounded isosceles trapezoid is 530-540 mm, the upper base length H is 95-105 mm, the height J is 580-590 mm, and the rounded arc radius r is 25-35 mm.

[0008] The electromagnetic stirring container uses a flow stabilizer, the bottom wall thickness is 110 mm, and the bottom wall is embedded with truncated cone-shaped magnesium carbon bricks with a thickness of 80 mm.

[0009] The electromagnetic stirring package uses a flow stabilizer, and the thickness of the annular side wall is 75 mm.

[0010] The inner contour of the cross section W of the electromagnetic stirring middle bag parallel to the upper end face and the bottom wall is a second rounded isosceles trapezoid, and the lower base length K of the second rounded isosceles trapezoid is 535mm, the upper base length L is 99mm, the height M is 633mm, and the rounded arc radius R is 55mm.

[0011] The above-mentioned electromagnetic stirring middle bag uses a current stabilizer, and an isosceles trapezoidal fixing groove is provided on the outer surface of the bottom wall below the lower base of the first rounded isosceles trapezoid, along a direction parallel to the lower base of the first rounded isosceles trapezoid; an isosceles trapezoidal fixing groove is also provided on the outer surface of the bottom wall below the upper base of the first rounded isosceles trapezoid, along a direction parallel to the upper base of the first rounded isosceles trapezoid; the cross-section of the isosceles trapezoidal fixing groove is a trapezoid, the lower base of the isosceles trapezoidal fixing groove is on the outside, the upper base is on the inside, and the upper base and the waist are rounded transition structures.

[0012] The electromagnetic stirring center package flow stabilizer, the distance X between the notch of the isosceles trapezoidal fixed groove and the bottom surface of the electromagnetic stirring center package flow stabilizer is 40mm, the height Y of the isosceles trapezoidal fixed groove is 40mm, and the length Z of the lower base of the isosceles trapezoid is 40mm.

[0013] The above-mentioned electromagnetic stirring center flow stabilizer has a right-angled trapezoidal boss on the inner wall of the annular side wall. Along the longitudinal direction of the electromagnetic stirring center flow stabilizer: the cross-section of the right-angled trapezoidal boss is a right-angled trapezoid, and the right-angled side of the right-angled trapezoidal boss is flush with the upper end surface, and the lower bottom side of the right-angled trapezoidal boss is flush with the inner wall of the annular side wall.

[0014] The electromagnetic stirring package uses a flow stabilizer, and the lower base length N of the right-angled trapezoidal boss is 70 mm, the upper base length P is 50 mm, and the height Q is 25 mm.

[0015] The electromagnetic stirring package uses a flow stabilizer, and a lifting ear is installed on the upper end surface.

[0016] The electromagnetic stirring bag uses a flow stabilizer, the flow stabilization chamber has a depth of 220 mm, the outer contour of the upper end surface is a cut-angle isosceles trapezoid, and the inner contour is a first rounded isosceles trapezoid;

[0017] The length of the lower base A of the cut-angle isosceles trapezoid is 661 mm, the length of the upper base B is 192.2 mm, and the height C is 783 mm; the isosceles trapezoid formed with the two sides of the cut-angle isosceles trapezoid as the waist is a regular isosceles trapezoid, and the length of the lower base D of the regular isosceles trapezoid is 823 mm, the length of the upper base E is 303 mm, and the height F is 625 mm;

[0018] The lower base length G of the first rounded isosceles trapezoid is 535 mm, the upper base length H is 99 mm, the height J is 583 mm, and the rounded arc radius r is 30 mm.

[0019] The material of the amorphous refractory material of the flow stabilizer is corundum or corundum mullite (chemical composition Al2O3≥80% or Al2O3+SiO2≥80%).

[0020] The technical solution of the utility model has achieved the following beneficial technical effects:

[0021] The utility model discloses a flow stabilizer for electromagnetic stirring tundish, which is installed in the impact zone of the tundish. The molten steel in the ladle enters the flow stabilization cavity through the long water inlet, which can limit the impact eddy flow zone of the molten steel to a smaller range, reduce the scouring of the ladle wall by the molten steel when entering the tundish, and can effectively promote the floating of inclusions in the molten steel, thereby improving the crystallization degree of the molten steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the cross-sectional structure of a current stabilizer for electromagnetic stirring in a package according to the utility model;

[0023] Figure 2 for Figure 1 The schematic diagram of the top view of the structure of the current stabilizer used in the electromagnetic stirring package is shown;

[0024] Figure 3 for Figure 1 The schematic diagram of the top view of the structure of the current stabilizer used in the electromagnetic stirring package is shown;

[0025] Figure 4 for Figure 1 The schematic diagram of the top view of the structure of the current stabilizer used in the electromagnetic stirring package is shown;

[0026] Figure 5 This is a schematic diagram of the three-dimensional structure of the current stabilizer for electromagnetic stirring in the utility model (the lifting ears are omitted);

[0027] Figure 6 This is a schematic diagram of the three-dimensional structure of the electromagnetic stirring center package current stabilizer from another angle of the utility model (the lifting ears are omitted);

[0028] Figure 7 Original three-dimensional spatial model of the watershed;

[0029] Figure 8 Overall flow diagram;

[0030] Fig. 9 Velocity vector diagram of symmetry surface;

[0031] Fig.10 Velocity vector diagram of the cross section where the stopper rod is located;

[0032] Fig.11 Liquid surface velocity cloud diagram;

[0033] Fig.12 RTD curves for each stream.

[0034] The reference numerals in the figure are as follows: 1-bottom wall; 2-annular side wall; 3-steady flow cavity; 4-upper end surface; 5-truncated cone-shaped magnesium carbon brick; 6-isosceles trapezoidal fixing groove; 7-right-angled trapezoidal boss; 8-lifting ear. DETAILED DESCRIPTION

[0035] like Figure 1 , Figure 5 and Figure 6 As shown, the electromagnetic stirring center flow stabilizer of this embodiment has a bottom wall 1 and an annular side wall 2, and the bottom wall 1 and the annular side wall 2 form a flow stabilizing chamber 3 with an upward opening for accommodating molten steel, and the depth of the flow stabilizing chamber 3 is 220 mm, and the outer contour of the upper end face 4 is a cut-angle isosceles trapezoid, and the inner contour is a first rounded isosceles trapezoid.

[0036] like Figures 1 to 4 As shown, the lower base length A of the cut-angle isosceles trapezoid is 661mm, the upper base length B is 192.2mm, and the height C is 783mm; the isosceles trapezoid formed with the two sides of the cut-angle isosceles trapezoid as the waist is a regular isosceles trapezoid, and the lower base length D of the regular isosceles trapezoid is 823mm, the upper base length E is 303mm, and the height F is 625mm; the lower base length G of the first rounded isosceles trapezoid is 535mm, the upper base length H is 99mm, the height J is 583mm, and the rounded arc radius r is 30mm.

[0037] In this embodiment, the bottom wall 1 has a thickness of 110 mm, and a truncated cone-shaped magnesium carbon brick 5 with a thickness of 80 mm is embedded in the bottom wall 1, and the annular side wall 2 has a thickness of 75 mm.

[0038] like Figure 1 and Figure 2 As shown, the inner contour of the cross section W parallel to the upper end face 4 and the bottom wall 1 is a second rounded isosceles trapezoid, the lower base length K of the second rounded isosceles trapezoid is 535 mm, the upper base length L is 99 mm, the height M is 633 mm, and the rounded arc radius R is 55 mm.

[0039] like Figure 5 and Figure 6 As shown, on the outer surface of the bottom wall 1 below the lower base of the first rounded isosceles trapezoid, an isosceles trapezoid fixing groove 6 is opened in a direction parallel to the lower base of the first rounded isosceles trapezoid; on the outer surface of the bottom wall 1 below the upper base of the first rounded isosceles trapezoid, an isosceles trapezoid fixing groove 6 is also opened in a direction parallel to the upper base of the first rounded isosceles trapezoid; the cross-section of the isosceles trapezoid fixing groove 6 is a trapezoid, the lower base of the isosceles trapezoid fixing groove 6 is on the outside, the upper base is on the inside, and the upper base and the waist are a rounded transition structure.

[0040] like Figure 1 As shown, the distance X between the notch of the isosceles trapezoidal fixing groove 6 and the bottom surface of the electromagnetic stirring center stabilizer is 40 mm, the height Y of the isosceles trapezoidal fixing groove 6 is 40 mm, and the length Z of the lower base of the isosceles trapezoid is 40 mm. The inner wall of the annular side wall 2 is provided with a right-angled trapezoidal boss 7, along the longitudinal direction of the electromagnetic stirring center stabilizer: the cross-section of the right-angled trapezoidal boss 7 is a right-angled trapezoid, and the right-angled side of the right-angled trapezoidal boss 7 is flush with the upper end face 4, and the lower base of the right-angled trapezoidal boss 7 is flush with the inner wall of the annular side wall 2. The lower base length N of the right-angled trapezoidal boss 7 is 70 mm, the upper base length P is 50 mm, and the height Q is 25 mm. A lifting ear 8 is installed on the upper end face 4.

[0041] The electromagnetic stirring tundish flow stabilizer of this embodiment is installed in the tundish impact zone. The molten steel in the ladle enters the flow stabilization chamber through the long water inlet, which can limit the eddy current area impacted by the molten steel to a smaller range, reduce the scouring of the ladle wall by the molten steel when entering the tundish, and can effectively promote the floating of inclusions in the molten steel, thereby improving the degree of crystallization of the molten steel.

[0042] The flow field simulation test of the middle package using the package stabilizer in this embodiment

[0043] 1. The specific test parameters are shown in Table 1 below:

[0044] Table 1 Parameters required for the test

[0045] name parameter Billet size 280mm×380mm Pulling speed 0.62m / min~0.85m / min Inner and outer diameter of shroud 75mm / 135mm Working fluid level 700mm~850mm Long shroud insertion depth 200mm~300mm

[0046] 2. Simulation Analysis

[0047] 2.1 CAD digital object modeling

[0048] The flow field is a space domain filled with fluid, so the CAD model is a complex geometric body filled with molten steel. Considering the symmetric characteristics of the flow field space, 1 / 2 of the flow field space is taken as the calculation object, and the symmetry surface is processed using a numerical symmetry boundary. The original three-dimensional space model of the flow field is as follows Figure 7 As shown:

[0049] 2.2 CAE Digital Object Modeling

[0050] The test object is divided into tetrahedral grids, and the number of grids is about 750,000.

[0051] 2.3 CAE Model

[0052] In this experiment, the Stokes equations were used to describe the flow phenomenon of molten steel. The finite volume method was used for calculation. The k-ε double equation mathematical model was used to describe the turbulent flow characteristics of molten steel. The turbulent flow in the near-wall area was treated with an optimized wall function.

[0053] 2.4 Boundary Conditions

[0054] According to the working conditions of the test object in service, the boundary conditions are set. For details, please see the table below:

[0055] Table 2 Boundary conditions

[0056] area Boundary conditions parameter Entrance Speed ​​​​entry Speed ​​is calculated from casting parameters Free surface Free slip wall Tundish wall No-slip wall Symmetrical plane Symmetrical Boundary exit Open Borders Relative pressure is 0

[0057] 3. Results of Flow Field of Liquid Steel in Tundish

[0058] In order to intuitively display the flow field results, streamline diagram and vector diagram are used to describe the calculation results. The details are as follows:

[0059] 3.1. The overall streamline diagram is as follows Figure 8 shown.

[0060] 3.2. The velocity vector diagram of the symmetry surface is shown in Fig. 9 shown.

[0061] 3.3、The velocity vector diagram of the cross section where the stopper rod is located is as follows Fig.10 shown.

[0062] 3.4、Liquid surface velocity cloud diagram Fig.11 shown.

[0063] 4. Experimental Results Analysis

[0064] 4.1、RTD curve analysis Fig.12 The RTD curve analysis results are shown in Table 3.

[0065] Table 3 RTD curve analysis results

[0066]

[0067] 4.2. Analysis of inclusion removal rate is shown in Table 4

[0068] Table 4 Calculation results of inclusion removal rate

[0069]

[0070]

[0071] In this embodiment, the flow stabilizer in the tundish is used together with the guide pipe to further optimize the flow field in the tundish, improve the removal rate of inclusions, and thus improve the quality of steel. The structure can improve the removal of inclusions of different particle sizes to a certain extent, especially for the removal of large particle size inclusions, and the improvement effect is more obvious. Overall, the residence time of each flow of molten steel in the tundish using this structure is another beneficial attempt to eliminate the dead zone, and the overall average residence time and the dead zone volume are almost the same.

[0072] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the claims of this patent application.

Claims

1. A flow stabilizer for electromagnetic stirring, characterized in that: The invention comprises a bottom wall (1) and an annular side wall (2), wherein the bottom wall (1) and the annular side wall (2) form a steady flow chamber (3) with an opening facing upwards for accommodating molten steel, wherein the depth of the steady flow chamber (3) is 215-225 mm, and the outer contour of the upper end face (4) is a cut-angle isosceles trapezoid and the inner contour is a first rounded isosceles trapezoid; The length A of the lower base of the chamfered isosceles trapezoid is 655-665mm, the length B of the upper base is 190-195mm, and the height C is 780-785mm; the isosceles trapezoid formed by the two sides of the chamfered isosceles trapezoid is a regular isosceles trapezoid, and the length D of the lower base of the regular isosceles trapezoid is 820-825mm, the length E of the upper base is 300-305mm, and the height F is 620-630mm; The lower base length G of the first rounded isosceles trapezoid is 530-540 mm, the upper base length H is 95-105 mm, the height J is 580-590 mm, and the rounded arc radius r is 25-35 mm.

2. A flow stabilizer for electromagnetic stirring in a bag according to claim 1, characterized in that: The bottom wall (1) has a thickness of 110 mm, and a truncated cone-shaped magnesium carbon brick (5) with a thickness of 80 mm is embedded in the bottom wall (1).

3. A flow stabilizer for electromagnetic stirring in a ladle according to claim 1, characterized in that: The thickness of the annular side wall (2) is 75 mm.

4. The electromagnetic stirring current stabilizer according to claim 1, characterized in that: The inner contour of the cross section W parallel to the upper end face (4) and the bottom wall (1) is a second rounded isosceles trapezoid, wherein the lower base length K of the second rounded isosceles trapezoid is 535 mm, the upper base length L is 99 mm, the height M is 633 mm, and the rounded arc radius R is 55 mm.

5. The electromagnetic stirring current stabilizer for a medium-sized package according to claim 1, characterized in that: An isosceles trapezoid fixing groove (6) is provided on the outer side surface of the bottom wall (1) below the lower base of the first rounded isosceles trapezoid, in a direction parallel to the lower base of the first rounded isosceles trapezoid; an isosceles trapezoid fixing groove (6) is also provided on the outer side surface of the bottom wall (1) below the upper base of the first rounded isosceles trapezoid, in a direction parallel to the upper base of the first rounded isosceles trapezoid; the cross section of the isosceles trapezoid fixing groove (6) is a trapezoid, the lower base of the isosceles trapezoid fixing groove (6) is on the outer side, the upper base is on the inner side, and the upper base and the waist are in a rounded transition structure.

6. A flow stabilizer for electromagnetic stirring in a ladle according to claim 5, characterized in that: The distance X between the notch of the isosceles trapezoidal fixing groove (6) and the bottom surface of the electromagnetic stirring center package current stabilizer is 40 mm, the height Y of the isosceles trapezoidal fixing groove (6) is 40 mm, and the length Z of the lower base of the isosceles trapezoid is 40 mm.

7. The electromagnetic stirring current stabilizer for a package according to claim 1, characterized in that: The inner wall of the annular side wall (2) is provided with a right-angled trapezoidal boss (7), and along the longitudinal direction of the electromagnetic stirring center stabilizer: the cross-section of the right-angled trapezoidal boss (7) is a right-angled trapezoid, and the right-angled side of the right-angled trapezoidal boss (7) is flush with the upper end face (4), and the lower bottom side of the right-angled trapezoidal boss (7) is flush with the inner wall of the annular side wall (2).

8. A flow stabilizer for electromagnetic stirring in a ladle according to claim 7, characterized in that: The right-angled trapezoidal boss (7) has a lower base length N of 70 mm, an upper base length P of 50 mm, and a height Q of 25 mm.

9. The current stabilizer for electromagnetic stirring in a ladle according to claim 7, characterized in that: A lifting lug (8) is installed on the upper end surface (4).

10. The electromagnetic stirring current stabilizer for a medium-sized package according to claim 1, characterized in that: The depth of the steady flow chamber (3) is 220 mm; The lower base length A of the cut-angle isosceles trapezoid is 661 mm, the upper base length B is 192.2 mm, and the height C is 783 mm; the lower base length D of the regular isosceles trapezoid is 823 mm, the upper base length E is 303 mm, and the height F is 625 mm; The lower base length G of the first rounded isosceles trapezoid is 535 mm, the upper base length H is 99 mm, the height J is 583 mm, and the rounded arc radius r is 30 mm.

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