Guide and distribution pipe of electromagnetic stirring tundish

Abstract

The utility model discloses a guiding and shunting pipe of an electromagnetic stirring tundish, which comprises a first straight section and a second straight section which are connected with each other, the included angle between the first straight section and the second straight section is larger than 0 degree, a steel inlet hole is arranged in the first straight section, one end of the steel inlet hole penetrates through a steel inlet panel at the end part of the first straight section, and the other end of the steel inlet hole penetrates into the second straight section. A first steel tapping hole is formed in a second outer side wall panel of the second straight section, a second steel tapping hole is formed in a second inner side wall panel of the second straight section, and the liquid inlet end of the first steel tapping hole and the liquid inlet end of the second steel tapping hole are both in fluid communication with the steel inlet hole; and the first tapping hole and the second tapping hole are gradually raised from the liquid inlet end to the liquid outlet end. By designing the diversion pipe, the flowing and stirring effects of molten steel in the tundish can be enhanced, the dead zone volume can be reduced, the impurity removal rate can be improved, and steel slag is promoted to float upwards when passing through the diversion pipe, so that the quality of the molten steel in the tundish is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of metallurgical refractory materials, and is specifically a flow guide and diverter pipe for an electromagnetic stirring package. Background Art

[0002] Electromagnetic stirring of the tundish uses electromagnetic force to strengthen the movement of molten steel in the liquid phase hole in the tundish, which plays a role in strengthening the convection, heat transfer and mass transfer process of the molten steel. Each diversion port of the diversion pipe distributes the molten steel to each water inlet. The size design of the diversion pipe has a crucial influence on the flow of molten steel, the flow field in the tundish, the dead zone volume and the inclusion removal rate. Utility Model Content

[0003] Therefore, the technical problem to be solved by the utility model is to provide a guide and diverter pipe for an electromagnetic stirring ladle which can improve the quality of molten steel.

[0004] To solve the above technical problems, the utility model provides the following technical solutions: a guide and diverter pipe for an electromagnetic stirring ladle, comprising a first straight section and a second straight section which are connected to each other and have an angle greater than 0°, a steel inlet hole being provided in the first straight section, one end of the steel inlet hole passing through a steel inlet panel at the end of the first straight section, and the other end of the steel inlet hole passing through the second straight section, a first steel outlet being provided on the second outer side wall panel of the second straight section, and a second steel outlet being provided on the second inner side wall panel of the second straight section, the second outer side wall panel and the second inner side wall panel being two opposite side walls, the liquid inlet end of the first steel outlet and the liquid inlet end of the second steel outlet are both fluidly conductive with the steel inlet hole, and the first steel outlet and the second steel outlet gradually rise from the liquid inlet end to the liquid outlet end.

[0005] In the above-mentioned electromagnetic stirring middle ladle, on the cross section of the second straight section perpendicular to the axis of the steel inlet hole: the angle between the first steel outlet and the horizontal line from the liquid inlet end to the liquid outlet end is 2°, and the angle between the second steel outlet and the horizontal line from the liquid inlet end to the liquid outlet end is also 2°. The upward inclination of the steel outlet is to prevent the impact on the bottom of the middle ladle from causing damage to the middle ladle, and also to form a good flow field, uniform composition and temperature, and promote the floating of inclusions.

[0006] In the above-mentioned electromagnetic stirring middle package, the diameter of the steel inlet hole is 142 mm, the diameter of the first steel outlet is 92 mm, and the diameter of the second steel outlet is 58 mm.

[0007] In the above-mentioned guide and diverter pipe of the electromagnetic stirring ladle, the outlet end of the first steel outlet is inclined in the direction away from the first straight section, that is, the outlet end of the first steel outlet is offset from the direction perpendicular to the flow direction of the molten steel in the second straight section towards the extension line of the flow direction of the molten steel in the steel inlet hole close to the second straight section.

[0008] The guide and diverter pipe of the above-mentioned electromagnetic stirring bag, on the horizontal plane passing through the axis of the steel inlet hole: the angle d between the axis of the first steel outlet and the axis of the steel inlet hole is 68°, that is, the angle d between the flow direction of molten steel in the second straight section and the steel outlet direction of the first steel outlet is 68°, the axis of the second steel outlet is perpendicular to the axis of the steel inlet hole; the angle between the axis of the first steel outlet and the axis of the second steel outlet is 158°.

[0009] In the above-mentioned guide and diverter pipe of the electromagnetic stirring bag, the angle c between the axis of the steel inlet hole located in the first straight section and the axis of the steel inlet hole located in the second straight section is 140°.

[0010] In the above-mentioned electromagnetic stirring middle package, the guide and diverter pipe is on the horizontal plane passing through the axis of the steel inlet hole: the angle between the first outer wall panel of the first straight section and the second outer wall panel of the second straight section is 155°, the angle between the first inner wall panel of the first straight section and the second inner wall panel of the second straight section is 140°, the first inner wall panel and the second inner wall panel are connected by an arc transition, the first outer wall panel and the second outer wall panel are also connected by an arc transition, and the arc radius of the arc transition is 150 mm.

[0011] In the above-mentioned guide and diverter pipe of the electromagnetic stirring bag, the bottom wall panel and the top wall panel of the first straight section are parallel horizontal planes, and the bottom wall panel and the top wall panel of the second straight section are also parallel horizontal planes; the spacing between the second outer wall panel and the second inner wall panel gradually increases from the point where they are connected with the bottom wall panel to the point where they are connected with the top wall panel; the steel inlet panel gradually inclines in the direction approaching the second straight section from the point where it is connected with the bottom wall panel to the point where it is connected with the top wall panel; the first outer wall panel on the first straight section gradually inclines in the direction away from the axis of the steel inlet hole from the point where it is connected with the bottom wall panel to the point where it is connected with the top wall panel.

[0012] In the above-mentioned flow guide and diverter pipe of the electromagnetic stirring bag, the angle a between the planes where the second outer wall panel and the bottom wall panel are located is 80°, and the angle b between the planes where the second inner wall panel and the bottom wall panel are located is 85°.

[0013] In the above-mentioned guide and diverter pipe of the electromagnetic stirring ladle, the angle f between the first outer wall panel and the bottom wall panel is 80°, the angle g between the first inner wall panel and the bottom wall panel is 90°; the angle e between the steel inlet panel and the bottom wall panel is 95°.

[0014] The guide and diverter pipe of the electromagnetic stirring bag is cast and made of corundum spinel or corundum mullite (Al2O3≥80%, MgO≤10% or Al2O3+SiO2≥80%).

[0015] The technical solution of the utility model has achieved the following beneficial technical effects:

[0016] 1. By designing the size of the diverter pipe and the angle of the steel outlet, the flow and stirring effect of the molten steel in the tundish can be enhanced, the dead zone volume can be reduced, the impurity removal rate can be improved, and the slag can be promoted to float when passing through the diverter pipe, thereby improving the quality of the molten steel in the tundish; when the tundish and the diverter pipe are used together, this structure further optimizes the flow field of the tundish, improves the inclusion removal rate, and thus improves the quality of steel. For inclusions of different particle sizes, the removal can be improved to a certain extent, especially for the removal of large-size inclusions, the improvement effect is more obvious.

[0017] 2. The structure of the guide and diverter pipe enables the electromagnetic stirring to have a better heat supplement effect, and at the same time optimizes the flow field of the tundish so that the temperature of the steel flow from the guide and diverter pipe is basically the same when entering the various water outlets of the tundish. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A three-dimensional structural schematic diagram of the utility model;

[0019] Figure 2 A schematic diagram of the structure of the utility model when viewed from above;

[0020] Figure 3 A front view structural schematic diagram of the utility model;

[0021] Figure 4 A side structural schematic diagram of the utility model;

[0022] Figure 5 A schematic diagram of the cross-sectional structure of the utility model;

[0023] Figure 6 A schematic diagram of the structure of the utility model from a top view;

[0024] Figure 7 The utility model Figure 6 Schematic diagram of the cross-sectional structure at AA;

[0025] Figure 8 Original three-dimensional spatial model of the watershed;

[0026] Fig. 9 Overall flow diagram;

[0027] Fig.10 Velocity vector diagram of symmetry surface;

[0028] Fig.11 Velocity vector diagram of the cross section where the stopper rod is located;

[0029] Fig.12 Liquid surface velocity cloud diagram;

[0030] Fig.13RTD curves for each stream.

[0031] The reference numerals in the figure are as follows: 1-first straight section; 2-second straight section; 3-steel inlet hole; 4-steel inlet panel; 5-second outer wall panel; 6-second inner wall panel; 7-first steel outlet; 8-second steel outlet; 9-bottom wall panel; 10-top wall panel; 11-first outer wall panel; 12-first inner wall panel. DETAILED DESCRIPTION

[0032] In this embodiment, a flow guide pipe of an electromagnetic stirring package is shown in FIG. Figure 1-2 , comprising a first straight section 1 and a second straight section 2 which are connected to each other and have an angle greater than 0°, a steel inlet hole 3 is provided in the first straight section 1, one end of the steel inlet hole 3 passes through a steel inlet panel 4 at the end of the first straight section 1, and the other end of the steel inlet hole 3 penetrates into the second straight section 2, a first steel outlet 7 is provided on the second outer side wall panel 5 of the second straight section 2, a second steel outlet 8 is provided on the second inner side wall panel 6 of the second straight section 2, the second outer side wall panel 5 and the second inner side wall panel 6 are two opposite side walls, the liquid inlet end of the first steel outlet 7 and the liquid inlet end of the second steel outlet 8 are both fluidly conductive with the steel inlet hole 3, and the first steel outlet 7 and the second steel outlet 8 gradually rise from the liquid inlet end to the liquid outlet end.

[0033] like Figure 3 As shown, in the cross section of the second straight section 2 perpendicular to the axis of the steel inlet hole 3: the angle X between the first steel outlet 7 and the horizontal line from the liquid inlet end to the liquid outlet end is 2°, and the angle Y between the second steel outlet 8 and the horizontal line from the liquid inlet end to the liquid outlet end is also 2°.

[0034] like Figure 2-3 As shown, the diameter of the steel inlet hole 3 is 142 mm, the diameter of the first steel outlet 7 is 92 mm, the diameter of the second steel outlet 8 is 58 mm, and the angle between the axis of the first steel outlet 7 and the axis of the second steel outlet 8 is 158°.

[0035] like Figure 5 As shown, the outlet end of the first steel outlet 7 is inclined toward the direction away from the first straight section 1, that is, the outlet end of the first steel outlet 7 is offset from the direction perpendicular to the flow direction of the molten steel in the second straight section 2 toward the extension line of the flow direction of the molten steel in the steel inlet hole 3 on the second straight section 2; on the horizontal plane passing through the axis of the steel inlet hole 3: the angle d between the axis of the first steel outlet 7 and the axis of the steel inlet hole 3 is 68°, that is, the angle d between the flow direction of the molten steel in the second straight section 2 and the steel outlet direction of the first steel outlet 7 is 68°, and the axis of the second steel outlet 8 is perpendicular to the axis of the steel inlet hole 3.

[0036] like Figure 5As shown, the angle c between the axis of the steel inlet hole 3 located in the first straight section 1 and the axis of the steel inlet hole 3 located in the second straight section 2 is 140°.

[0037] like Figure 5 As shown, on the horizontal plane passing through the axis of the steel entry hole 3: the angle between the first outer side wall panel 11 of the first straight section 1 and the second outer side wall panel 5 of the second straight section 2 is 155°, the angle between the first inner side wall panel 12 of the first straight section 1 and the second inner side wall panel 6 of the second straight section 2 is 140°, the first inner side wall panel 12 and the second inner side wall panel 6 are connected by arc transition, the first outer side wall panel 11 and the second outer side wall panel 5 are also connected by arc transition, and the arc radius of the arc transition is 150 mm.

[0038] like Figure 1 As shown, the bottom wall panel 9 and the top wall panel 10 of the first straight section 1 are parallel horizontal planes, and the bottom wall panel 9 and the top wall panel 10 of the second straight section 2 are also parallel horizontal planes; the spacing between the second outer wall panel 5 and the second inner wall panel 6 gradually increases from the connection with the bottom wall panel 9 to the connection with the top wall panel 10; the steel inlet panel 4 gradually inclines toward the second straight section 2 from the connection with the bottom wall panel 9 to the connection with the top wall panel 10; the first outer wall panel 11 on the first straight section 1 gradually inclines toward the direction away from the axis of the steel inlet hole 3 from the connection with the bottom wall panel 9 to the connection with the top wall panel 10.

[0039] like Figure 1 As shown, the included angle a between the planes where the second outer side wall panel 5 and the bottom wall panel 9 are located is 80°, and the included angle b between the planes where the second inner side wall panel 6 and the bottom wall panel 9 are located is 85°; Figure 6-7 As shown, the included angle f between the first outer side wall panel 11 and the bottom wall panel 9 is 80°, the included angle g between the first inner side wall panel 12 and the bottom wall panel 9 is 90°; the included angle e between the steel inlet panel 4 and the bottom wall panel 9 is 95°.

[0040] The flow field simulation test of the middle bag using the guide and diverter pipe of the electromagnetic stirring middle bag of this embodiment is as follows:

[0041] Table 1 Parameters required for the test

[0042] 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

[0043] 2. Simulation Analysis

[0044] 2.1 CAD digital object modeling

[0045] 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 8 As shown:

[0046] 2.2 CAE Digital Object Modeling

[0047] The test object is divided into tetrahedral grids, and the number of grids is about 750,000.

[0048] 2.3 CAE Model

[0049] 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.

[0050] 2.4 Boundary Conditions

[0051] According to the working conditions of the test object in service, the boundary conditions are set. For details, please see the following table:

[0052] Table 2 Boundary conditions

[0053] 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

[0054] 3. Results of Flow Field of Liquid Steel in Tundish

[0055] 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:

[0056] 3.1. The overall streamline diagram is as follows Fig. 9 shown.

[0057] 3.2. The velocity vector diagram of the symmetry surface is shown in Fig.10 shown.

[0058] 3.3、The velocity vector diagram of the cross section where the stopper rod is located is as follows Fig.11 shown.

[0059] 3.4、Liquid surface velocity cloud diagram Fig.12 shown.

[0060] 4. Experimental Results Analysis

[0061] 4.1、RTD curve analysis Fig.13 The RTD curve analysis results are shown in Table 3.

[0062] Table 3 RTD curve analysis results

[0063] 4.2. Analysis of inclusion removal rate is shown in Table 4

[0064] Table 4 Calculation results of inclusion removal rate

[0065]

[0066] The guide and diverter pipe of the electromagnetic stirring tundish in this embodiment further optimizes the tundish flow field when used in the tundish, improves the inclusion removal rate, and thus improves 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.

[0067] 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 guide pipe for an electromagnetic stirring package, characterized in that: The invention comprises a first straight section (1) and a second straight section (2) which are connected to each other and have an angle greater than 0°, wherein a steel inlet hole (3) is provided in the first straight section (1), one end of the steel inlet hole (3) passes through a steel inlet panel (4) at the end of the first straight section (1), and the other end of the steel inlet hole (3) passes into the second straight section (2), a first steel outlet (7) is provided on a second outer wall panel (5) of the second straight section (2), and a second steel outlet (8) is provided on a second inner wall panel (6) of the second straight section (2), the second outer wall panel (5) and the second inner wall panel (6) are two opposite side walls, the liquid inlet end of the first steel outlet (7) and the liquid inlet end of the second steel outlet (8) are both in fluid communication with the steel inlet hole (3), and the first steel outlet (7) and the second steel outlet (8) gradually rise from the liquid inlet end to the liquid outlet end.

2. The flow guide pipe for electromagnetic stirring package according to claim 1, characterized in that: In the cross section of the second straight section (2) perpendicular to the axis of the steel inlet hole (3): the angle between the first steel outlet (7) and the horizontal line from the liquid inlet end to the liquid outlet end is 2°, and the angle between the second steel outlet (8) and the horizontal line from the liquid inlet end to the liquid outlet end is also 2°.

3. The flow guide pipe of the electromagnetic stirring bag according to claim 1, characterized in that: The diameter of the steel inlet hole (3) is 142 mm, the diameter of the first steel outlet (7) is 92 mm, and the diameter of the second steel outlet (8) is 58 mm.

4. The flow guide and diverter tube of the electromagnetic stirring package according to claim 1, characterized in that: The outlet end of the first steel outlet (7) is inclined in a direction away from the first straight section (1), that is, the outlet end of the first steel outlet (7) is offset from a direction perpendicular to the flow direction of the molten steel in the second straight section (2) toward an extension line of the flow direction of the molten steel in the steel inlet hole (3) on the second straight section (2).

5. The flow guide and diverter pipe of the electromagnetic stirring bag according to claim 4, characterized in that: On a horizontal plane passing through the axis of the steel inlet hole (3): the angle d between the axis of the first steel outlet (7) and the axis of the steel inlet hole (3) is 68°, that is, the angle d between the flow direction of molten steel in the second straight section (2) and the steel outlet direction of the first steel outlet (7) is 68°, and the axis of the second steel outlet (8) is perpendicular to the axis of the steel inlet hole (3); the angle between the axis of the first steel outlet (7) and the axis of the second steel outlet (8) is 158°.

6. A flow guide and diverter tube for an electromagnetic stirring bag according to any one of claims 1 to 5, characterized in that: The included angle c between the axis of the steel inlet hole (3) located in the first straight section (1) and the axis of the steel inlet hole (3) located in the second straight section (2) is 140°.

7. A flow guide and diverter tube for an electromagnetic stirring bag according to any one of claims 1 to 5, characterized in that: On the horizontal plane passing through the axis of the steel entry hole (3): the included angle between the first outer wall panel (11) of the first straight section (1) and the second outer wall panel (5) of the second straight section (2) is 155°, the included angle between the first inner wall panel (12) of the first straight section (1) and the second inner wall panel (6) of the second straight section (2) is 140°, the first inner wall panel (12) and the second inner wall panel (6) are connected by an arc transition, the first outer wall panel (11) and the second outer wall panel (5) are also connected by an arc transition, and the arc radius of the arc transition is 150 mm.

8. The flow guide and diverter pipe of the electromagnetic stirring bag according to claim 7, characterized in that: The bottom wall panel (9) and the top wall panel (10) of the first straight section (1) are parallel horizontal planes, and the bottom wall panel (9) and the top wall panel (10) of the second straight section (2) are also parallel horizontal planes; the spacing between the second outer wall panel (5) and the second inner wall panel (6) gradually increases from the point where it is connected to the bottom wall panel (9) to the point where it is connected to the top wall panel (10); the steel inlet panel (4) gradually inclines in a direction approaching the second straight section (2) from the point where it is connected to the bottom wall panel (9) to the point where it is connected to the top wall panel (10); the first outer wall panel (11) on the first straight section (1) gradually inclines in a direction away from the axis of the steel inlet hole (3) from the point where it is connected to the bottom wall panel (9) to the point where it is connected to the top wall panel (10).

9. The flow guide and diverter pipe of the electromagnetic stirring bag according to claim 8, characterized in that: The included angle a of the plane where the second outer wall panel (5) and the bottom wall panel (9) are located is 80°, and the included angle b of the plane where the second inner wall panel (6) and the bottom wall panel (9) are located is 85°.

10. The flow guide and diverter tube of the electromagnetic stirring bag according to claim 8, characterized in that: The included angle f between the first outer side wall panel (11) and the bottom wall panel (9) is 80°, the included angle g between the first inner side wall panel (12) and the bottom wall panel (9) is 90°; and the included angle e between the steel inlet panel (4) and the bottom wall panel (9) is 95°.

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