A mold copper tube for reducing corner wear

Abstract

The present invention relates to a mold copper tube for reducing corner wear, belonging to the technical field of continuous casting. The inner cavity of the mold copper tube is rectangular. One end of the mold copper tube is the upper copper tube opening, and the other end is the lower copper tube opening. A copper tube transition opening is provided on the mold copper tube near the lower copper tube opening; from the upper copper tube opening to the copper tube transition opening is the first section of the copper tube, and the inner cavity of the first section of the copper tube gradually shrinks from the upper copper tube opening to the copper tube transition opening according to the power function curve law; from the copper tube transition opening to the lower copper tube opening is the second section of the copper tube, and the inner cavity of the second section of the copper tube gradually increases from the copper tube transition opening to the lower copper tube opening; the inward deformation amount of the inner wall at the corner of the inner cavity of the mold copper tube is less than that of the inner wall of the face, so as to increase the air gap generated at the corner, avoid the temperature of the corner of the billet being too low, make the circumferential temperature and stress distribution of the billet uniform, avoid the generation of corner or partial corner quality defects, provide guarantee for stable high-speed continuous casting, while reducing the serious problem of copper tube corner wear and improving the service life of the copper tube.

Description

Technical Field

[0001] The present invention belongs to the technical field of continuous casting, and relates to a mold copper tube for reducing corner wear. Background Art

[0002] The high-speed continuous casting technology can reduce the number of strands of the continuous casting machine, and reduce the construction investment and production operation costs. The mold copper tube is an important cooling device of the continuous casting machine and is the key to realizing high speed.

[0003] At present, the mold copper tubes mostly adopt single taper, multi-taper and parabolic inner cavities. The inner cavities with single taper and multi-taper shapes do not conform to the solidification law of continuous casting molten steel and cannot meet the use requirements of the mold; the cavity shape of the parabola makes the cooling characteristics of the mold copper tube more in line with the solidification and cooling change law of continuous casting molten steel. However, due to two-dimensional heat transfer at the corner of the slab, the cooling rate at the corner is the fastest, resulting in the corner temperature being significantly lower than the surface temperature, causing corner cracks and folding defects in the continuous casting slab. During the direct rolling process of the continuous casting slab, since the temperature at the corner of the slab is the lowest, in order to ensure the uniform consistency of the slab cross-section temperature during direct rolling, electromagnetic induction heat compensation and gas heat compensation are often used to heat the corner of the continuous casting slab, resulting in energy consumption and greenhouse gas emissions.

[0004] To solve the above problems, the patent document "Power Function Mold Copper Tube" with the document number CN108907121A proposes a mold copper tube with an inner cavity gradually decreasing in a power function, and the diagonal taper of the mold copper tube is greater than the surface taper to make up for the air gap generated at the corner. However, the inner wall at the lower opening of the mold copper tube will deform inward, squeezing the slab with the initially formed primary shell, affecting the slab quality and reducing the service life of the mold copper tube. The patent document "A Mold Copper Tube" with the document number CN111250668A proposes a mold copper tube divided into upper and lower sections. The inner cavity of the second section of the copper tube gradually increases from the transition port of the copper tube to the lower opening of the copper tube, avoiding squeezing the slab and damaging the slab quality, and greatly reducing the wear of the lower opening of the copper tube. However, the inward deformation amount at the corner of this mold copper tube is greater than that at the surface, resulting in serious wear at the corner of the copper tube, affecting the slab quality and the service life of the copper tube. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a mold copper tube for reducing corner wear to solve the problem that the corner of the copper tube in the prior art is severely worn, affecting the slab quality and the service life of the copper tube.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A mold copper tube for reducing corner wear, the inner cavity of the mold copper tube is rectangular, one end of the mold copper tube is the upper copper tube opening, the other end is the lower copper tube opening, and a copper tube transition opening is provided on the mold copper tube near the lower copper tube opening; from the upper copper tube opening to the copper tube transition opening is the first section of the copper tube, and the inner cavity of the first section of the copper tube gradually shrinks from the upper copper tube opening to the copper tube transition opening according to the law of a power function curve; from the copper tube transition opening to the lower copper tube opening is the second section of the copper tube, and the inner cavity of the second section of the copper tube gradually becomes larger from the copper tube transition opening to the lower copper tube opening; the inward deformation amount of the inner wall at the corner of the inner cavity of the mold copper tube is less than the inward deformation amount of the inner wall of the face; half of the difference between the inner cavity width of the upper copper tube opening and the inner cavity width of the copper tube transition opening is the face taper δ1 of the inner walls in the length direction of the relatively arranged mold copper tube, and half of the difference between the inner cavity diagonal length of the upper copper tube opening and the inner cavity diagonal length of the copper tube transition opening is the diagonal taper ω. There are rounded corners at the intersections of the four inner walls of the mold copper tube, and the radius of the rounded corner at the upper copper tube opening is R 上 , and the radius of the rounded corner at the lower copper tube opening is R 下 , R 下 = R 上 -(δ1 - ω).

[0008] Optionally, R 上 is 3% - 16% of the inner cavity length or the inner cavity width of the upper copper tube opening.

[0009] Optionally, from the face inner wall at any position of the cross-section at any vertical height of the mold copper tube to the rounded corner, a transition curve is used to smoothly connect the straight line segment of the inner wall of the copper tube and the arc of the rounded corner of the copper tube, and the curvature of the transition curve changes continuously.

[0010] Optionally, half of the difference between the inner cavity length of the upper copper tube opening and the inner cavity length of the copper tube transition opening is the face taper δ2 of the inner walls in the width direction of the relatively arranged mold copper tube; the vertical height from any position on the inner wall of the first section of the copper tube to the upper copper tube opening is h;

[0011] wherein, a1 > 0, m1 < 0;

[0012] wherein, a2 > 0, m2 < 0;

[0013] wherein, a3 > 0, m3 < 0;

[0014] a1, m1, a2, m2, a3, m3 are all constants.

[0015] Optionally, 0 ≤ ω ≤ 0.8δ1.

[0016] Optionally, the inner cavity length of the lower opening of the copper tube is 0.1 - 0.4 mm greater than the inner cavity length of the transition opening of the copper tube; the inner cavity width of the lower opening of the copper tube is 0.1 - 0.4 mm greater than the inner cavity width of the transition opening of the copper tube.

[0017] Optionally, the vertical height H1 of the first section of the copper tube is 600 - 1200 mm, and the vertical height H2 of the second section of the copper tube is 50 - 150 mm.

[0018] Optionally, the inner cavity length of the upper opening of the copper tube is 2 - 3 mm greater than the inner cavity width of the upper opening of the copper tube.

[0019] Optionally, the inner cavity length of the lower opening of the copper tube is 2 - 3 mm greater than the inner cavity width of the lower opening of the copper tube.

[0020] Optionally, the inner cavity length of the transition opening of the copper tube is 2 - 3 mm greater than the inner cavity width of the transition opening of the copper tube.

[0021] The beneficial effects of the present invention are as follows:

[0022] (1) The crystallizer copper tube is divided into two sections. The inner cavity of the first section of the copper tube from the upper opening of the copper tube to the transition opening of the copper tube follows the variation law of gradually decreasing in a power function form from the upper opening of the copper tube to the transition opening of the copper tube; the inner cavity of the second section of the copper tube from the transition opening of the copper tube to the lower opening of the copper tube is designed according to the law of gradually increasing from the transition opening of the copper tube to the lower opening of the copper tube, reserving a certain space for the inward deformation at the lower opening of the copper tube, avoiding squeezing the billet and damaging the billet quality, and greatly reducing the wear of the lower opening of the copper tube.

[0023] (2) The inward deformation amount at the corner of the crystallizer copper tube is less than the inward deformation amount at the face, which can increase the air gap generated at the corner, avoid the temperature at the corner of the billet being too low, make the circumferential temperature and stress distribution of the billet uniform, avoid the generation of quality defects at the corner or the partial corner, reduce the problem of serious wear at the corner of the copper tube, and improve the service life of the copper tube.

[0024] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent description, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be learned from the practice of the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the accompanying drawings, where:

[0026] Figure 1 It is a schematic diagram in the vertical height direction of the crystallizer copper tube for reducing corner wear of the present invention;

[0027] Figure 2It is a top view schematic diagram of the upper mouth of the copper pipe;

[0028] Figure 3 It is a bottom view schematic diagram of the lower mouth of the copper pipe.

[0029] Reference numerals: upper mouth 1 of the copper pipe, lower mouth 2 of the copper pipe, transition port 3 of the copper pipe, second side wall 4, first side wall 5, transition curve 6. Specific embodiments

[0030] The following specific examples illustrate the embodiments of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0031] Among them, the drawings are only for illustrative purposes, showing only schematic diagrams, not physical diagrams, and should not be construed as a limitation to the present invention; in order to better illustrate the embodiments of the present invention, some components in the drawings will be omitted, enlarged or reduced, which do not represent the dimensions of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0032] In the drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "rear", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only for illustrative purposes and should not be construed as a limitation to the present invention. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0033] Please refer to Figures 1 to 3, A mold copper tube for reducing corner wear. The inner cavity of the mold copper tube is rectangular. One end of the mold copper tube is the copper tube upper opening 1, and the other end is the copper tube lower opening 2. A copper tube transition opening 3 is provided on the mold copper tube near the copper tube lower opening 2. From the copper tube upper opening 1 to the copper tube transition opening 3 is the first section of the copper tube. The inner cavity of the first section of the copper tube gradually shrinks from the copper tube upper opening 1 to the copper tube transition opening 3 according to the power function curve law. From the copper tube transition opening 3 to the copper tube lower opening 2 is the second section of the copper tube. The inner cavity of the second section of the copper tube gradually increases from the copper tube transition opening 3 to the copper tube lower opening 2. The inward deformation amount of the inner wall at the corner of the inner cavity of the mold copper tube is less than that of the inner wall of the face.

[0034] The present invention divides the mold copper tube into two sections. The inner cavity of the first section of the copper tube from the copper tube upper opening 1 to the copper tube transition opening 3 follows the change law of gradually shrinking in a power function form from the copper tube upper opening 1 to the copper tube transition opening 3. The inner cavity of the second section of the copper tube from the copper tube transition opening 3 to the copper tube lower opening 2 is designed according to the law of gradually increasing from the copper tube transition opening 3 to the copper tube lower opening 2, reserving a certain space for the inward deformation at the copper tube lower opening 2, avoiding squeezing the billet and damaging the billet quality, and greatly reducing the wear of the copper tube lower opening 2. The inward deformation amount of the corner of the mold copper tube is less than that of the face, which can increase the air gap generated at the corner, avoid the temperature of the billet corner being too low, make the circumferential temperature and stress distribution of the billet uniform, avoid the generation of corner or partial corner quality defects, provide guarantee for stable high-speed continuous casting, while reducing the serious problem of copper tube corner wear and improving the service life of the copper tube.

[0035] Embodiment

[0036] A mold copper tube for reducing corner wear, as Figures 1 to 3 shown. The inner cavity of the mold copper tube is rectangular. One end of the mold copper tube is the copper tube upper opening 1, and the other end is the copper tube lower opening 3. A copper tube transition opening 2 is provided on the mold copper tube near the copper tube lower opening. From the copper tube upper opening 1 to the copper tube transition opening 2 is the first section of the copper tube. The inner cavity of the first section of the copper tube gradually shrinks from the copper tube upper opening 1 to the copper tube transition opening 2 according to the power function curve law, which is more in line with the solidification shrinkage law of the billet in the longitudinal direction. From the copper tube transition opening 2 to the copper tube lower opening 3 is the second section of the copper tube. The inner cavity of the second section of the copper tube gradually increases from the copper tube transition opening 2 to the copper tube lower opening 3, reserving a certain space for the inward deformation at the copper tube lower opening 3, avoiding squeezing the billet and damaging the billet quality, and greatly reducing the wear of the copper tube lower opening 3.

[0037] As Figure 2 and Figure 3 shown, set the inner cavity length of the copper tube upper opening 1 as l 11 , and the inner cavity width of the copper tube upper opening 1 as l 12 ; the inner cavity length of the copper tube transition opening 2 is l 21 , and the inner cavity width of the copper tube transition opening 2 is l 22; The inner cavity length of the lower opening 3 of the copper tube is l 31 , and the inner cavity width of the lower opening 3 of the copper tube is l 32 ; The vertical height of the first section of the copper tube is H1, and the vertical height of the second section of the copper tube is H2.

[0038] The inner cavity length l of the lower opening 3 of the copper tube 31 is 0.1 - 0.4 mm larger than the inner cavity length l of the transition opening 2 of the copper tube 21 ; The inner cavity width l of the lower opening 3 of the copper tube 32 is 0.1 - 0.4 mm larger than the inner cavity width l of the transition opening 2 of the copper tube 22 . The vertical height of the mold copper tube, that is, the sum of the vertical height H1 of the first section of the copper tube and the vertical height H2 of the second section of the copper tube, is 600 - 1200 mm, and the vertical height H2 of the second section of the copper tube is 50 - 150 mm.

[0039] The inner cavity length l of the upper opening 1 of the copper tube 11 is greater than the inner cavity length l of the transition opening 2 of the copper tube 21 , and the inner cavity width l of the upper opening 1 of the copper tube 12 is greater than the inner cavity width l of the transition opening 2 of the copper tube 22 . Half of the difference between the inner cavity width l of the upper opening 1 of the copper tube 12 and the inner cavity width l of the transition opening 2 of the copper tube 22 is the face taper δ1 of one pair of opposite inner walls (the first side wall 5) in the length direction of the mold copper tube; Half of the difference between the inner cavity length l of the upper opening 1 of the copper tube 11 and the inner cavity length l of the transition opening 2 of the copper tube 21 is the face taper δ2 of the other pair of opposite inner walls (the second side wall 4) in the width direction of the mold copper tube; Half of the difference between the inner cavity diagonal length of the upper opening 1 of the copper tube and the inner cavity diagonal length of the transition opening 2 of the copper tube is the diagonal taper ω; The vertical height from any position on the inner wall of the first section of the copper tube to the upper opening 1 of the copper tube is h; Wherein:

[0040] Wherein, α1 > 0, m1 < 0;

[0041] Wherein, a2 > 0, m2 < 0;

[0042] Wherein, a3 > 0, m3 < 0;

[0043] a1, m1, a2, m2, a3, m3 are all constants, and 0 ≤ ω ≤ 0.8δ1.

[0044] As Figure 3 shown, there are fillets at the intersections of the four inner walls of the mold copper tube, and the fillet radius of the upper opening 1 of the copper tube is R 上 , R上 is the inner cavity length l of the upper opening 1 of the copper tube 11 or the inner cavity width l of the upper opening 1 of the copper tube 12 is 3% - 16% of; the radius of the chamfer at the lower opening 3 of the copper tube is R 下 , where:

[0045] R 下 = R 上 -(δ1 - ω);

[0046] From the inner wall of the face at any position of the vertical height of the copper tube to the chamfered corner, the transition curve 6 smoothly connects the straight segment of the inner wall of the copper tube and the arc of the chamfered corner of the copper tube, and the curvature of the transition curve 6 changes continuously.

[0047] In addition, the inner cavity length l of the upper opening 1 of the copper tube 11 is 2 - 3 mm larger than the inner cavity width l of the upper opening 1 of the copper tube 12 ; the inner cavity length l of the lower opening 3 of the copper tube 31 is 2 - 3 mm larger than the inner cavity width l of the lower opening 3 of the copper tube 32 ; the inner cavity length l of the transition opening 2 of the copper tube 21 is 2 - 3 mm larger than the inner cavity width l of the transition opening 2 of the copper tube 22 is 2 - 3 mm larger.

[0048] In summary, the first - segment surface taper of the crystallizer copper tube of the present invention adopts a power - function curve, providing a guarantee for stable high - speed continuous casting; the inner wall of the second segment of the crystallizer copper tube gradually changes from the inner wall to the outer wall, and the inner cavity gradually expands, reserving a certain space for the inward deformation of the lower inner wall, which can greatly reduce the wear of the lower opening of the copper tube; the inward deformation amount at the corner of the crystallizer copper tube is less than that at the face, increasing the air gap generated at the corner, avoiding too low temperature at the corner of the billet, making the circumferential temperature and stress distribution of the billet uniform, avoiding quality defects at the corner or near - corner, reducing the problem of serious wear at the corner of the copper tube, and improving the service life of the copper tube. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial value.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the present technical solution, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A mold copper tube for reducing corner wear, characterized in that: The inner cavity of the mold copper tube is rectangular. One end of the mold copper tube is the upper copper tube opening, and the other end is the lower copper tube opening. A copper tube transition opening is provided on the mold copper tube near the lower copper tube opening. From the upper copper tube opening to the copper tube transition opening is the first section of the copper tube. The inner cavity of the first section of the copper tube gradually narrows from the upper copper tube opening to the copper tube transition opening according to the law of a power function curve. From the copper tube transition opening to the lower copper tube opening is the second section of the copper tube. The inner cavity of the second section of the copper tube gradually enlarges from the copper tube transition opening to the lower copper tube opening. The inward deformation amount of the inner wall at the corner of the inner cavity of the mold copper tube is less than that of the inner wall of the face. Half of the difference between the inner cavity width of the upper copper tube opening and the inner cavity width of the copper tube transition opening is the face taper of the inner walls in the length direction of the relatively arranged mold copper tube , and half of the difference between the diagonal length of the inner cavity of the upper copper tube opening and the diagonal length of the inner cavity of the copper tube transition opening is the diagonal taper . Chamfers are provided at the intersections of the four inner walls of the mold copper tube. The radius of the chamfer at the upper copper tube opening is R 上 , and the radius of the chamfer at the lower copper tube opening is R 下 , R 下 = R 上 ( ) From the inner wall of the cross-section at any position in the vertical height of the crystallizer copper tube to the rounded corner, a transition curve is used to smoothly connect the straight section of the inner wall of the copper tube and the arc of the rounded corner of the copper tube, and the curvature of the transition curve changes continuously.

2. The crystallizer copper tube for reducing corner wear according to claim 1, wherein: R 上 It is 3% - 16% of the inner cavity length or the inner cavity width of the upper opening of the copper tube.

3. The crystallizer copper tube for reducing corner wear as described in claim 1, wherein: Half of the difference between the inner cavity length of the upper opening of the copper tube and the inner cavity length of the transition port of the copper tube is the face taper of the inner walls of the copper tube of the mold in the relatively set width direction. ; The vertical height from any position on the inner wall of the first section of the copper tube to the upper opening of the copper tube is h; ; wherein, > 0, < 0; ; wherein, > 0, < 0; ; wherein, > 0, < 0; , , , , , are all constants.

4. The crystallizer copper tube for reducing corner wear according to claim 3, characterized in that: 0 ≤ 0.8 。 5. The crystallizer copper tube for reducing corner wear according to claim 1, wherein: The inner cavity length of the lower opening of the copper tube is 0.1 - 0.4 mm larger than the inner cavity length of the transition opening of the copper tube; the inner cavity width of the lower opening of the copper tube is 0.1 - 0.4 mm larger than the inner cavity width of the transition opening of the copper tube.

6. The crystallizer copper tube for reducing corner wear according to claim 1, wherein: The vertical height H1 of the first section of the copper tube is 600 - 1200 mm, and the vertical height H2 of the second section of the copper tube is 50 - 150 mm.

7. The crystallizer copper tube for reducing corner wear according to claim 1, characterized in that: The inner cavity length of the upper opening of the copper tube is 2 - 3 mm larger than the inner cavity width of the upper opening of the copper tube.

8. The crystallizer copper tube for reducing corner wear according to claim 1, characterized in that: The inner cavity length of the lower opening of the copper tube is 2 - 3 mm larger than the inner cavity width of the lower opening of the copper tube.

9. The crystallizer copper tube for reducing corner wear according to claim 1, characterized in that: The inner cavity length of the transition opening of the copper tube is 2 - 3 mm larger than the inner cavity width of the transition opening of the copper tube.

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