Method for improving internal quality of casting blank through super-large-section special-shaped blank
By setting multiple pressure rollers on the narrow face of the irregular billet, and using specially designed waist-drum shaped pressure rollers, the problem of improving the internal quality of the irregular billet was solved, and efficient improvement of the internal quality of the billet and the improvement of the flaw detection pass rate were achieved.
Patent Information
- Application Number
- CN202511142199.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-15
- Publication Date
- 2025-11-28
AI Technical Summary
Existing technologies are insufficient to effectively improve the internal quality of ultra-large H-beam billets, especially shrinkage cavities and porosity defects. Traditional methods are difficult to apply to billets and cannot meet the flaw detection requirements of high-end customers.
Multiple pairs of specially shaped pressing rollers are set on the narrow face of the ultra-large cross-section irregular billet. The pressing rollers are located in the area 1m to 5m before the end of solidification, with each pair spaced more than 0.5m apart. The pressing amount is gradually increased along the billet pulling direction. Pressing rollers with shapes such as waist drum are designed. The pressing amount on the narrow face is more than 5% of the width of the flange top of the irregular billet.
The localized pressing design significantly improves the internal quality of irregularly shaped billets, reduces shrinkage cavities and porosity, increases the pass rate of flaw detection, and meets the needs of high-end customers.
Smart Images
Figure CN121017486A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of continuous casting of shaped billets, in particular to a method for improving the internal quality of a super-section shaped billet. BACKGROUND
[0002] H-beams are widely used in the fields of construction and bridges, and in recent years, customers have increasingly demanded super-large specifications and super-high performance of H-beams. As a near-net shape product, a super-section shaped billet has an incomparable advantage in the rolling production of super-large specification H-beams, and therefore it is of great significance to research and develop the quality control technology of super-section shaped billets.
[0003] In the rolling production of super-large specification H-beams, it is difficult to improve the internal quality of the rolled material, especially to meet the flaw detection requirements of high-end customers for H-beams, which increases the production difficulty exponentially. The traditional method for eliminating the core shrinkage and porosity defects of the billet is to use large compression ratio rolling in the rolling process, but this method increases the rolling cost and limits the size of the H-beam rolled material, which cannot meet the production requirements of super-large and super-thick specification H-beams. Therefore, the key to solving the problem of improving the internal quality of super-large and super-thick specification H-beams is still to produce super-section shaped billets with excellent core quality.
[0004] To improve the internal quality of large-section billets and reduce shrinkage and porosity defects, the currently widely used technology is the billet pressing technology, that is, a pressing roller is arranged at a position before the end of the solidification of the billet to press the billet to different degrees to reduce the defects such as porosity and shrinkage. This technology has achieved good application results in thick slab, square billet and round billet, and can significantly improve the internal quality of the billet. However, due to the complex geometry of the shaped billet, it is difficult to apply the pressing technology, and currently there is no excellent application case and mature pressing technology in the shaped billet continuous casting. The research work on improving the quality of the shaped billet is mostly concentrated in the optimization design of the copper plate internal cooling water channel, the adjustment of the crystallizer cooling water volume and the optimization of the secondary cooling process. These research works have obvious effect on improving the external quality of the billet, but cannot fully meet the demand for improving the core quality of super-large specification shaped billets. SUMMARY
[0005] The present application aims to provide a method for improving the internal quality of a super-section shaped billet, which is used to improve the internal quality of the billet and thus improve the quality of the rolled product, meet the flaw detection requirements of high-end customers for super-large specification H-beams, and solve the problem of internal quality control of super-section shaped billets.
[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions:
[0007] The application discloses a method for improving the internal quality of a large-section beam blank, and relates to the technical field of continuous casting.
[0008] Further, the large-section beam blank is in an H shape, the left and right sides of the H shape are referred to as narrow sides, and the upper and lower sides of the H shape are referred to as wide sides; the narrow sides are two parallel planes and are divided into a left narrow side and a right narrow side; the wide sides are two symmetrical concave surfaces, the concave surfaces comprise a middle concave web, two side convex top wings, and an inclined surface connecting the web and the top wings, and the intersection between the inclined surface and the web is connected through an R corner.
[0009] Further, the middle part of the press-down roller is provided with a drum body in a waist drum shape, the center of the drum body is aligned with the middle line of the narrow side of the large-section beam blank, and the two sides of the press-down roller are drum surfaces which are symmetrically distributed along the center of the drum body.
[0010] Further, the distance L of the drum surfaces is designed according to the section size of the large-section beam blank and the solidification characteristics of the steel grade.
[0011] Further, the press-down amount of the press-down roller is a waist diameter difference, and the waist diameter difference is the difference between the maximum diameter D1 of the middle part of the drum body and the diameter D2 of the drum surface.
[0012] Further, the diameters of the two ends of the press-down roller are consistent with the diameters of the narrow side clamping rollers of the large-section beam blank.
[0013] Compared with the prior art, the application has the following beneficial effects:
[0014] 1. The method for improving the internal quality of the large-section beam blank can realize local press-down of the narrow side of the beam blank automatically, and the scheme is feasible.
[0015] 2. The method for improving the internal quality of the large-section beam blank can obviously improve the internal quality of the large-section beam blank, and the specially designed waist drum-shaped press-down roller is simple and convenient to process. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 The application discloses a method for improving the internal quality of a large-section beam blank, and relates to the technical field of continuous casting.
[0017] Figure 2 Figure 1 is a structural diagram of a narrow-face pinch roll of a super-section beam blank according to the present application.
[0018] In the figure: 1, web; 2, wing top; 3, bevel; 4, R angle; 5, left narrow face; 6, right narrow face; 9, drum body; 10, drum face. DETAILED DESCRIPTION
[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0020] The present application provides a method for improving the internal quality of a super-section beam blank, as shown in Figure 1 The super-section beam blank is in the shape of H, and the left and right sides of the H-shaped blank are referred to as narrow faces, which are divided into a left narrow face 5 and a right narrow face 6 in the figure, and the upper and lower sides of the H-shaped blank are referred to as wide faces. The narrow faces are two parallel planes, and the wide faces are two symmetrical concave surfaces, which include a web 1 recessed in the middle, wing tops 2 protruding on both sides, a bevel 3 connecting the web 1 and the wing tops 2, and an R angle 4 formed by the intersection of the bevel 3 and the web 1. In use, the specific method is as follows:
[0021] A plurality of pairs of special-shaped pinch rolls are arranged on the narrow face of the super-section beam blank, as shown in Figures 1-2 The pinch rolls are located in a region 1 m to 5 m before the solidification end, each pair of pinch rolls is spaced apart by more than 0.5 m, the pinch amount of each pair of pinch rolls gradually increases along the direction of drawing the blank, and the total pinch amount is more than 5% of the width of the wing top 2 of the beam blank.
[0022] As shown in Figure 2 The roll diameters at both ends of the pinch roll are consistent with the roll diameters of the pinch rolls clamping the narrow face of the beam blank, which can minimize the amount of modification work on the casting machine; the middle part of the special-shaped pinch roll is designed as a unique drum-shaped or other locally protruding shape, and the highest point of the protruding center is aligned with the center line of the narrow face of the beam blank; the arc-shaped protruding design of the plurality of pairs of pinch rolls realizes multi-segment local pinch of the narrow face of the beam blank, thereby reducing the core shrinkage and porosity in the triangular area of the beam blank, improving segregation, and achieving the goal of improving the internal quality of the beam blank.
[0023] The middle part of the pinch roll provided in the embodiment is a unique drum-shaped design, the center of the drum body 9 is aligned with the center line of the narrow face of the bloom, the drum faces 10 on both sides are symmetrically distributed along the center of the drum body 9, and the drum face spacing L is designed according to the cross-sectional size of the bloom and the solidification characteristics of the steel grade; in the embodiment, L=310mm, and the waist narrowing amount (the difference between the maximum diameter D1 of the drum body and the diameter D2 of the drum face) of the four pairs of pinch rolls is respectively set to 10mm, 20mm, 30mm and 40mm.
[0024] In the above embodiment, the present application realizes multi-section local pressing of the narrow face of the bloom during the continuous casting process by using the arc-shaped protruding design of the middle part of the drum body 9 of the pinch roll, thereby reducing the core shrinkage and porosity of the triangular area of the bloom, improving the segregation, and achieving the purpose of improving the internal quality of the bloom.
[0025] In summary: the method for improving the internal quality of the bloom provided by the present application realizes local pressing of the narrow face of the bloom by multi-section local pressing design, without changing the roller mechanism of the narrow face of the caster, and only needs to replace the conventional cylindrical clamping roll with a specially designed drum-shaped or other shape of local protruding pinch roll, which can automatically realize local pressing of the narrow face of the bloom, and the scheme is feasible. Secondly, the multi-section local pressing process of the narrow face of the bloom designed based on the method of the present application can significantly improve the internal quality of the bloom of the super large section bloom. In addition, the drum-shaped or other shape of pinch roll specially designed based on the method of the present application is simple and convenient to process, and only needs to be slightly adjusted to the processing program of the original cylindrical clamping roll to realize it.
[0026] The above is only one of the more optimal schemes based on the method of the present application, which can significantly improve the internal quality of the bloom of the super large section bloom and greatly improve the flaw detection qualification rate of the corresponding super large and thick H-shaped steel.
[0027] Based on the method of the present application, various structure parameters of the pinch roll including but not limited to drum-shaped, bowling pin-shaped, and rugby ball-shaped can be designed to realize the function of local pressing of the narrow face of the bloom. All methods and equipment for improving the internal quality of the bloom by local pressing of the narrow face of the bloom during the continuous casting process based on the method of the present application belong to the protection scope of the present application.
Claims
1. A method for improving the internal quality of cast billets with ultra-large cross-section irregular shapes, characterized in that, This includes setting several pairs of specially shaped pressing rollers on the narrow face of the ultra-large cross-section irregular billet. The pressing rollers are located in the area 1m to 5m before the end of solidification. Each pair of pressing rollers is spaced more than 0.5m apart. The pressing amount of each pair of pressing rollers gradually increases along the billet pulling direction. The total pressing amount is more than 5% of the width of the flange top of the ultra-large cross-section irregular billet.
2. The method for improving the internal quality of a cast billet with an ultra-large cross-section and irregular shape as described in claim 1, characterized in that: The extra-large cross-section irregular billet is H-shaped. The left and right sides of the H-shape are called narrow faces, and the top and bottom sides of the H-shape are called wide faces. The narrow faces are two parallel planes, divided into a left narrow face (5) and a right narrow face (6). The wide faces are two symmetrical concave faces. The concave faces include a web (1) that is recessed in the middle, wing tops (2) that are protruding on both sides, and a slope (3) that connects the web (1) and the wing tops (2). The part where the slope (3) intersects with the web (1) is connected by a transition angle (4).
3. The method for improving the internal quality of a cast billet with an ultra-large cross-section and irregular shape as described in claim 1, characterized in that: The middle part of the pressing roller is set as a waist drum-shaped drum body (9), the center of the drum body (9) is aligned with the center line of the narrow face of the ultra-large cross-section irregular blank, and the two sides of the pressing roller are drum surfaces (10), which are symmetrically distributed along the center of the drum body (9).
4. The method for improving the internal quality of a cast billet with an ultra-large cross-section and irregular shape as described in claim 3, characterized in that: The spacing L of the drum surface (10) is designed according to the cross-sectional dimensions of the ultra-large cross-section irregular billet and the solidification characteristics of the steel grade.
5. The method for improving the internal quality of a cast billet with an ultra-large cross-section and irregular shape as described in claim 1, characterized in that: The amount of pressure applied by the pressing roller is the waist diameter difference, which is the difference between the maximum diameter D1 of the drum body (9) and the diameter D2 of the drum surface (10).
6. The method for improving the internal quality of a cast billet with an ultra-large cross-section and irregular shape as described in claim 1, characterized in that: The diameters of the two ends of the pressing roller are consistent with the diameters of the narrow-face clamping rollers for the extra-large cross-section irregular blank.