Method for improving internal quality of continuous casting billet
By adjusting the opening degree of the sector section of the continuous casting machine, especially reducing the opening degree of the fifth to seventh sections, the problems of segregation and looseness of the inner center of the casting blank are solved, and the internal quality of the casting blank is stable.
Patent Information
- Application Number
- CN202510302906.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-14
- Publication Date
- 2025-07-04
AI Technical Summary
In continuous casting production, there are problems of central segregation, central cracks and internal looseness inside the casting billet, which affects product quality and leads to difficulties in downstream processes.
By reasonably controlling the opening degree of the sector section of the continuous casting machine, especially reducing the opening degree of the sector section 5 to 7 to 96.5%-98.8% of the fourth section of the sector section, the effect of light pressure is achieved, compensating for the shrinkage at the end of solidification and improving the internal quality.
It has steadily improved the internal quality of the casting billet, basically eliminated internal cracks and looseness, and improved the internal quality of the product.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of metal casting production, and particularly relates to a method for improving the internal quality of continuous casting billets. Background Art
[0002] In continuous casting production, internal quality defects generally exist in the casting billets. With the continuous increase in the drawing speed of the continuous casting machine, the central segregation, central cracks, and internal porosity of the casting billets are further manifested, which affects the internal quality of the products and brings difficulties to the rolling process of downstream processes. Therefore, it must be solved.
[0003] Soft reduction refers to a technology that aims to reduce central segregation and eliminate central porosity and cracks, and slightly presses the casting billet at the end of solidification on the basis of the reduction of the roll gap, with the emphasis on improving the internal quality. Adopting soft reduction can prevent the formation of shrinkage voids, compensate for the shrinkage in the final solidification stage, eliminate central porosity and internal cracks, and reduce central macrosegregation.
[0004] The continuous casting machine currently in use in this factory was put into use in 2003. Due to the early production time and the immaturity of the soft reduction technology at that time, it could not be put into use. The inventor conducted detailed research and analysis to solve the problems of central segregation, central cracks, and internal porosity in the casting billets under the current production conditions. Considering the mechanical principle and low cost, the opening degree of the segment of the continuous casting machine was adjusted, so that the internal quality of the casting billets reached a good level. Summary of the Invention
[0005] In view of the above-mentioned prior art, the purpose of the present invention is to provide a method for improving the internal quality of continuous casting billets. During the production process of the continuous casting machine, a billet shell is formed in the mold, and the supply of molten steel in the billet shell is continuous. The volume shrinkage caused by the temperature difference of the molten steel can be compensated by the continuous supply of molten steel. Therefore, when considering the opening degree parameters of the continuous casting machine and calculating the solidification shrinkage characteristics of the casting billet, according to factors such as the steel grade, billet cross-section, drawing speed, and specific water volume of the molten steel, it is analyzed that the end of solidification of the current casting billet is at the positions of the fourth and fifth segments of the segment. By reasonably controlling the opening degree of the fifth to seventh segments of the segment, the purpose of soft reduction is achieved, and the purpose of stabilizing and improving the internal quality of the casting billet is achieved.
[0006] To achieve the above purpose, the present invention adopts the following technical solutions: The present invention provides a method for improving the internal quality of continuous casting billets, controlling the opening degree of the zero to fourth segments of the segment to be 162.50 - 165.00 mm, and adjusting the opening degree of the fifth to seventh segments of the continuous casting machine segment to reduce the opening degree of the fifth to seventh segments of the segment to 96.5% - 98.8% of the fourth segment of the segment.
[0008] Preferably, the upper opening of the zero segment of the segment is 164.75 - 164.80 mm, and the lower opening of the zero segment is 164.10 - 164.15 mm.
[0009] Preferably, the upper opening of the first segment of the segment is 164.10 - 164.15 mm, and the lower opening of the first segment is 163.78 - 163.83 mm.
[0010] Preferably, the upper opening of the second segment of the segment is 163.75 - 163.80 mm, and the lower opening of the second segment is 163.43 - 163.48 mm.
[0011] Preferably, the upper opening of the third segment of the segment is 163.38 - 163.43 mm, and the lower opening of the third segment is 163.06 - 163.10 mm.
[0012] Preferably, the upper opening of the fourth segment of the segment is 163.05 - 163.06 mm, and the lower opening of the fourth segment is 162.70 - 162.75 mm.
[0013] Preferably, the upper opening of the fifth segment of the segment is 160.50 mm, and the lower opening of the fifth segment is 158.00 mm.
[0014] Preferably, the upper and lower openings of the sixth to seventh segments of the segment are both 158.00 mm.
[0015] Advantages of the present invention:
[0016] By reasonably controlling the opening degrees of the zero to seventh segments of the segment, especially reducing the opening degrees of the fifth to seventh segments to 96.5% - 98.8% of that of the fourth segment, the present invention achieves the purpose of stabilizing and improving the internal quality of the continuous casting billet. Description of the drawings
[0017] Figure 1 It is the internal quality inspection report form of the continuous casting billet obtained in Example 1 of the present invention;
[0018] Figure 2 It is the structural schematic diagram of the segment in the present invention;
[0019] Wherein: 0 is the zero segment, 1 is the first segment, 2 is the second segment, 3 is the third segment, 4 is the fourth segment, 5 is the fifth segment, 6 is the sixth segment, and 7 is the seventh segment. Detailed implementation manners
[0020] It should be noted that the following detailed description is illustrative and is intended to provide further illustration of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.
[0021] To enable those skilled in the art to more clearly understand the technical solution of this application, the technical solution of this application will be described in detail below in conjunction with specific embodiments.
[0022] Embodiment 1:
[0023] A method for improving the internal quality of continuous casting billets: controlling the upper opening of the zero segment of the segment to be 164.80 mm and the lower opening to be 164.10 mm; the upper opening of the first segment of the segment to be 164.13 mm and the lower opening to be 163.81 mm; the upper opening of the second segment of the segment to be 163.77 mm and the lower opening to be 163.45 mm; the upper opening of the third segment of the segment to be 163.40 mm and the lower opening to be 163.09 mm; the upper opening of the fourth segment of the segment to be 163.06 mm and the lower opening to be 162.75 mm; the upper opening of the fifth segment of the segment to be 160.50 mm and the lower opening to be 158.00 mm; the upper and lower openings of the sixth to seventh segments of the segment are both 158.00 mm.
[0024] Embodiment 2:
[0025] A method for improving the internal quality of continuous casting billets: controlling the upper opening of the zero segment of the segment to be 164.75 mm and the lower opening to be 164.15 mm; the upper opening of the first segment of the segment to be 164.15 mm and the lower opening to be 163.83 mm; the upper opening of the second segment of the segment to be 163.80 mm and the lower opening to be 163.48 mm; the upper opening of the third segment of the segment to be 163.43 mm and the lower opening to be 163.10 mm; the upper opening of the fourth segment of the segment to be 163.05 mm and the lower opening to be 162.70 mm; the upper opening of the fifth segment of the segment to be 160.50 mm and the lower opening to be 158.00 mm; the upper and lower openings of the sixth to seventh segments of the segment are both 158.00 mm.
[0026] Comparative Example 1: A method for improving the internal quality of continuous casting billets: controlling the upper opening of the zero segment of the segment to be 164.80 mm and the lower opening to be 164.10 mm; the upper opening of the first segment of the segment to be 164.13 mm and the lower opening to be 163.81 mm; the upper opening of the second segment of the segment to be 163.77 mm and the lower opening to be 163.45 mm; the upper opening of the third segment of the segment to be 163.40 mm and the lower opening to be 163.09 mm; the upper opening of the fourth segment of the segment to be 163.06 mm and the lower opening to be 162.75 mm; the upper opening of the fifth segment of the segment to be 162.61 mm and the lower opening to be 162.50 mm; the upper opening of the sixth segment of the segment to be 162.44 mm and the lower opening to be 162.18 mm; the upper opening of the seventh segment of the segment to be 162.18 mm and the lower opening to be 162.18 mm.
[0028] Comparative Example 2: A method for improving the internal quality of a continuous casting billet: controlling the upper opening of the zero section of the sector segment to be 164.80 mm and the lower opening of the zero section to be 164.10 mm; the upper opening of the first section of the sector segment to be 164.13 mm and the lower opening of the first section to be 163.81 mm; the upper opening of the second section of the sector segment to be 163.77 mm and the lower opening of the second section to be 163.45 mm; the upper opening of the third section of the sector segment to be 163.40 mm and the lower opening of the third section to be 163.09 mm; the upper opening of the fourth section of the sector segment to be 163.06 mm and the lower opening of the fourth section to be 162.75 mm; the upper opening of the fifth section of the sector segment to be 161.61 mm and the lower opening of the fifth section to be 161.50 mm; the upper opening of the sixth section of the sector segment to be 161.44 mm and the lower opening of the sixth section to be 161.18 mm; the upper opening of the seventh section of the sector segment to be 161.18 mm and the lower opening of the seventh section to be 161.18 mm.
[0029] Comparative Example 3: A method for improving the internal quality of a continuous casting billet: controlling the upper opening of the zero section of the sector segment to be 164.80 mm, and the lower opening of the zero section to be 164.10 mm; the upper opening of the first section of the sector segment to be 164.13 mm, and the lower opening of the first section to be 163.81 mm; the upper opening of the second section of the sector segment to be 163.77 mm, and the lower opening of the second section to be 163.45 mm; the upper opening of the third section of the sector segment to be 163.40 mm, and the lower opening of the third section to be 163.09 mm; the upper opening of the fourth section of the sector segment to be 163.06 mm, and the lower opening of the fourth section to be 162.75 mm; the upper opening of the fifth section of the sector segment to be 157.75 mm, and the lower opening of the fifth section to be 156.50 mm; the upper opening of the sixth section of the sector segment to be 156.25 mm, and the lower opening of the sixth section to be 156.10 mm; the upper opening of the seventh section of the sector segment to be 156.10 mm, and the lower opening of the seventh section to be 156.10 mm.
[0030] In comparative example 3, the internal molten steel static pressure of the ingot is greater than the pressure of the fan-shaped segment clamping cylinder, causing the fan-shaped segment to be stretched open, and the narrow side of the ingot to have a slight bulging problem, accompanied by large running resistance of the fan-shaped segment and increased current of the fan-shaped segment motor, which affects production safety. The steel grade used in Examples 1-2 and Comparative Examples 1-3 is No. 45 steel grade.
[0031] The internal quality of the ingots obtained in Example 1-2 and Comparative Example 1-2 was tested, and the test results are shown in Table 1:
[0032] Table 1
[0033]
[0034] It can be seen from the above table that by reasonably controlling the opening of the fifth to seventh sectors, the internal cracks and internal porosity of the ingot can be basically eliminated, thereby improving the internal quality of the ingot.
[0035] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.
Claims
1. A method for improving the internal quality of continuous casting billets, characterized in that: Control the opening of the zero to fourth segments of the segment sector to be 162.50 - 165.00 mm, and adjust the opening of the fifth to seventh segments of the continuous casting machine segment sector to reduce the opening of the fifth to seventh segments of the segment sector to 96.5% - 98.8% of that of the fourth segment of the segment sector.
2. The method according to claim 1, wherein: The upper opening of the zero segment of the segment sector is 164.75 - 164.80 mm, and the lower opening of the zero segment is 164.10 - 164.15 mm.
3. The method according to claim 1, characterized in that: The upper opening of the first segment of the segment sector is 164.10 - 164.15 mm, and the lower opening of the first segment is 163.78 - 163.83 mm.
4. The method according to claim 1, characterized in that: The upper opening of the second segment of the segment sector is 163.75 - 163.80 mm, and the lower opening of the second segment is 163.43 - 163.48 mm.
5. The method according to claim 1, wherein: The upper opening of the third segment of the segment sector is 163.38 - 163.43 mm, and the lower opening of the third segment is 163.06 - 163.10 mm.
6. The method according to claim 1, wherein: The upper opening of the fourth segment of the segment sector is 163.05 - 163.06 mm, and the lower opening of the fourth segment is 162.70 - 162.75 mm.
7. The method according to claim 1, wherein: The upper opening of the fifth segment of the segment sector is 160.50 mm, and the lower opening of the fifth segment is 158.00 mm.
8. The method according to claim 1, wherein: The upper and lower openings of the sixth to seventh segments of the segment sector are both 158.00 mm.