A double ladle continuous casting production method of H-shaped steel and H-shaped steel

Abstract

The application provides a double ladle continuous casting production method of H-shaped steel and H-shaped steel, and the method comprises the following steps: preparing first molten steel and second molten steel of a first ladle and a second ladle respectively; the yield strength of a first flange is higher than that of a second flange; the first ladle and the second ladle are connected with a continuous casting crystallizer through a double-flow composite pouring nozzle, so that the first molten steel and the second molten steel are poured into the continuous casting crystallizer through the double-flow composite pouring nozzle; in the continuous casting process, the corresponding first flange forming area, second flange forming area and web forming area in the continuous casting crystallizer are independently cooled by using secondary cooling water; after the continuous casting is completed, a continuous casting billet is obtained; the continuous casting billet is heated and rolled to obtain H-shaped steel products with different performance flanges, so as to solve the problem that the current H-shaped steel production is mainly single ladle pouring, the two flanges have consistent composition and performance, and the personalized demand of single flange high strength cannot be met.

Description

Technical Field

[0001] This application relates to the field of metallurgical processes, and in particular to a double-ladle continuous casting production method for H-beams and the H-beams themselves. Background Technology

[0002] H-beams are widely used in many fields such as construction and machinery manufacturing due to their efficient cross-sectional properties. In certain specific applications, such as critical load-bearing nodes of large bridges and core load-bearing components of heavy machinery, one flange of an H-beam often needs to withstand complex forces such as concentrated loads and fatigue loads. This complex stress situation places extremely high demands on the local bearing capacity of the H-beam's single flange to meet the safety and stability requirements of the structure during long-term use.

[0003] To address these needs, the current main approach is to weld reinforcing plates to one flange to enhance the local load-bearing capacity of H-beams. Currently, most H-beam production uses a single-ladle casting process, resulting in H-beams with consistent composition and properties across both flanges. When high strength is required on one flange, an additional reinforcing plate is welded to that flange to increase its strength and enable it to withstand complex loads.

[0004] However, the connection between the reinforcing plate and the H-beam base material is mechanical, making stress concentration highly likely at the interface. During long-term service, this stress concentration can lead to delamination and cracking between the reinforcing plate and the base material, severely impacting structural reliability. Furthermore, the welding process involves a series of complex steps, including beveling, preheating, and post-weld heat treatment, increasing both the complexity and time cost of production and resulting in low efficiency. In addition, welding can easily generate internal defects such as porosity and slag inclusions, as well as external defects such as welding deformation, which further affect the overall safety and durability of the structure. Summary of the Invention

[0005] This application provides a double-ladle continuous casting production method for H-beams and the H-beams themselves, in order to solve the technical problem that existing H-beam production methods mostly use single-ladle casting, with both flanges having the same composition and properties, which cannot meet the personalized requirements of high strength on one side of the flange.

[0006] The first aspect of this application provides a method for producing H-beams using double-ladle continuous casting, comprising: Molten steel is prepared in a first ladle and a second ladle, respectively. The first molten steel is continuously cast and rolled in the first ladle to form a first flange, and the second molten steel is continuously cast and rolled in the second ladle to form a second flange. The yield strength of the first flange is higher than that of the second flange. The first ladle and the second ladle are connected to the continuous casting mold via a dual-flow composite gating nozzle, allowing the molten steel to be injected into the continuous casting mold through the nozzle. The dual-flow composite gating nozzle has a first inner cavity and a second inner cavity, which are respectively used to guide the molten steel from the first ladle and the second ladle. The first inner cavity has a first main outlet and a first side outlet, and the second inner cavity has a second main outlet and a second side outlet. The first main outlet is connected to the first flange forming area in the continuous casting mold, the second main outlet is connected to the second flange forming area in the continuous casting mold, and the first side outlet and the second side outlet are connected to the web forming area in the continuous casting mold. During the continuous casting process, secondary cooling water is used to perform independent cooling treatment on the sections corresponding to the first flange forming area, the second flange forming area, and the web forming area in the continuous casting crystallizer; after the continuous casting is completed, a continuous casting billet is obtained. The continuously cast billet is heated and then rolled to obtain an H-beam with different performance flanges.

[0007] In some embodiments, the carbon content and alloy element ratios of the first molten steel and the second molten steel are different.

[0008] In some embodiments, the step of injecting the first molten steel and the second molten steel into the continuous casting mold through the dual-flow composite gating nozzle includes: The first molten steel, ranging from 65% to 75% by weight, is injected into the first flange forming area of ​​the continuous casting mold through the first main outlet; the first molten steel, ranging from 25% to 35% by weight, is injected into the web forming area of ​​the continuous casting mold through the first side outlet. In addition, 65% to 75% by weight of the second molten steel is injected into the second flange forming region of the continuous casting mold through the second main outlet; and 25% to 35% by weight of the second molten steel is injected into the web forming region of the continuous casting mold through the second side outlet.

[0009] In some embodiments, the angle between the centerlines of the first side outlet and the second side outlet of the dual-flow composite injection nozzle and the vertical direction is within the range of 25° to 35°.

[0010] In some embodiments, the cooling intensity of the first flange forming region is lower than the cooling intensity of the second flange forming region.

[0011] In some embodiments, the secondary cooling water flow velocity in the first flange forming region is in the range of 1.8 m / s to 2.0 m / s; the secondary cooling water flow velocity in the second flange forming region is in the range of 2.4 m / s to 2.6 m / s; and the secondary cooling water flow velocity in the web forming region is in the range of 2.0 m / s to 2.2 m / s.

[0012] In some embodiments, the step of heating and rolling the continuously cast billet includes: After heating the continuously cast billet, it is rolled in 4 to 5 passes using a universal rolling mill; the rolling heating temperature is in the range of 1200°C to 1220°C.

[0013] A second aspect of this application provides an H-beam, comprising: The H-beam with different properties is produced by the double-ladle continuous casting production method of H-beams as described in any one of the first aspects above; the H-beam includes a first flange, a second flange and a web; the yield strength of the first flange is greater than the yield strength of the second flange; the chemical composition and mechanical properties of the web are between those of the first flange and the second flange.

[0014] This application provides a method for producing H-beams using double-ladle continuous casting and the H-beams themselves. The method includes: preparing molten steel in a first ladle and molten steel in a second ladle; forming a first flange by continuous casting and rolling of the first ladle, and forming a second flange by continuous casting and rolling of the second ladle; the yield strength of the first flange being higher than that of the second flange; connecting the first ladle and the second ladle to a continuous casting mold via a dual-flow composite gating nozzle, allowing the molten steel to be injected into the continuous casting mold through the dual-flow composite gating nozzle; the dual-flow composite gating nozzle having a first inner cavity and a second inner cavity, which are respectively used to guide the molten steel in the first ladle and the second ladle; and having a first main outlet in the first inner cavity. The second inner cavity is provided with a second main outlet and a second side outlet, and a first side outlet. The first main outlet is connected to the first flange forming area in the continuous casting mold, and the second main outlet is connected to the second flange forming area in the continuous casting mold. The first side outlet and the second side outlet are connected to the web forming area in the continuous casting mold. During the continuous casting process, secondary cooling water is used to perform independent cooling treatment on the areas corresponding to the first flange forming area, the second flange forming area, and the web forming area in the continuous casting mold. After the continuous casting is completed, a continuous casting billet is obtained. The continuous casting billet is heated and rolled to obtain an H-beam with different performance flanges. This allows the H-beam production to use double ladle casting, which can make the composition and performance of the two flanges inconsistent, thereby meeting the personalized requirement of high strength on one side flange. Attached Figure Description

[0015] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a flowchart of the double-ladle continuous casting production method for H-beams in this application; Figure 2 This is a schematic diagram of the structure of the dual-flow composite gating nozzle in this application; Figure 3 This is a cross-sectional view of the continuous casting crystallizer in this application. Detailed Implementation

[0017] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0018] Because some technologies use single-ladle casting for H-beam production, resulting in identical composition and properties for both flanges, this method cannot meet the personalized requirements of high strength on one side of the flange. To address this technical problem, this application provides a double-ladle continuous casting method for producing H-beams and the H-beams themselves. The double-ladle continuous casting method for producing H-beams and the H-beams themselves are described below: like Figure 1 The diagram shown is a flowchart of the double-ladle continuous casting production method for H-beams in this application. The first aspect of this application provides a method for producing H-beams using double-ladle continuous casting, comprising the following steps: S100: Molten steel in the first ladle and molten steel in the second ladle are prepared respectively; the first molten steel is continuously cast and rolled in the first ladle to form a first flange, and the second molten steel is continuously cast and rolled in the second ladle to form a second flange; the yield strength of the first flange is higher than that of the second flange; the carbon content and alloy element ratios of the first molten steel and the second molten steel are different.

[0019] For example, carbon is one of the most important and economical strengthening elements in steel. In steel, carbon can dissolve in ferrite to form a solid solution, producing a solid solution strengthening effect. Carbon is also a key element in the formation of carbides, and the dispersed distribution of carbides can significantly improve the strength of steel. Appropriately increasing the carbon content in the first batch of molten steel will cause more carbon atoms to dissolve in the ferrite lattice, resulting in lattice distortion, hindering dislocation movement, and thus increasing the yield strength of the steel.

[0020] For example, different alloying elements have different strengthening mechanisms in steel. By reasonably adjusting their proportions in the first and second molten steel, the difference in yield strength between the first and second flanges can be achieved.

[0021] For example, manganese is an excellent deoxidizer and desulfurizer, and it can significantly improve the strength of steel. It can dissolve in ferrite and cementite, producing solid solution strengthening, and it can also form manganese sulfide with sulfur, mitigating the harmful effects of sulfur. Appropriately increasing the manganese content in the first molten steel can effectively improve the yield strength of the first flange. Silicon is also a commonly used deoxidizer, dissolving in ferrite to produce solid solution strengthening, improving the strength and hardness of steel. Appropriately increasing the silicon content in the first molten steel helps to improve the yield strength of the first flange. Chromium can improve the hardenability of steel, forming fine and uniformly distributed carbides, producing a dispersion strengthening effect, significantly improving the strength and hardness of steel. Adding a certain amount of chromium to the first molten steel can effectively improve the yield strength of the first flange. Molybdenum can improve the hardenability and hot strength of steel, prevent temper brittleness, increase tempering stability, and allow the steel to maintain high strength at high temperatures. Adding molybdenum to the first molten steel can further improve the yield strength of the first flange.

[0022] First, the molten steel is prepared: according to the target performance requirements, the steel composition of the first ladle (for high-strength flanges) and the second ladle (for ordinary-strength flanges) is configured respectively. By adjusting the carbon content and the proportion of alloying elements, the strength potential of the molten steel in the first ladle is ensured to be higher than that in the second ladle.

[0023] S200: The first ladle and the second ladle are connected to the continuous casting mold through a dual-flow composite pouring nozzle, so that the first molten steel and the second molten steel are injected into the continuous casting mold through the dual-flow composite pouring nozzle; the dual-flow composite pouring nozzle is provided with a first inner cavity and a second inner cavity, which are respectively used to guide the molten steel from the first ladle and the second ladle; the first inner cavity is provided with a first main outlet and a first side outlet, and the second inner cavity is provided with a second main outlet and a second side outlet; the first main outlet is connected to the first flange forming area in the continuous casting mold, the second main outlet is connected to the second flange forming area in the continuous casting mold, and the first side outlet and the second side outlet are connected to the web forming area in the continuous casting mold; the angle between the centerline of the first side outlet and the second side outlet of the dual-flow composite pouring nozzle and the vertical direction is within the range of 25° to 35°.

[0024] Next, preparations are made for the continuous casting mold and gating system: a standard H-beam continuous casting mold is used. The core technology lies in the use of a composite gating nozzle specifically designed for dual ladles. This nozzle has independent and precisely controllable internal cavities, connecting to the first and second ladles respectively. Each cavity has two outlets: the main outlet directly aligns with and fills the corresponding flange forming cavity; the side outlet's centerline forms an angle of 25°~35° with the vertical direction, directing a portion of the molten steel towards the central forming area of ​​the mold's web. A schematic diagram of the nozzle structure is shown below. Figure 2As shown; Schematic diagram of the cross-section and pouring point of the H-beam continuous casting crystallizer. Figure 3 As shown.

[0025] The step of injecting the first molten steel and the second molten steel into the continuous casting mold through the dual-flow composite gating nozzle includes the following sub-steps: S210: 65% to 75% by weight of the first molten steel is injected into the first flange forming region of the continuous casting mold through the first main outlet; 25% to 35% by weight of the first molten steel is injected into the web forming region of the continuous casting mold through the first side outlet.

[0026] S220: and, 65% to 75% by weight of the second molten steel is injected into the second flange forming region of the continuous casting mold through the second main outlet; 25% to 35% by weight of the second molten steel is injected into the web forming region of the continuous casting mold through the second side outlet.

[0027] Then, synchronous pouring and flow control are performed: The pouring speed and flow rate of the first and second ladles are precisely coordinated using an independent stopper or slide control system. 65%–75% of the molten steel flowing from the first ladle is poured through its first main outlet, and 25%–35% through its first side outlet; similarly, 65%–75% of the molten steel flowing from the second ladle is poured through its second main outlet, and 25%–35% through its second side outlet. The control principle is to ensure that the vast majority of the molten steel fills its corresponding flanges through the main outlets, forming a pure flange body; simultaneously, a small portion of the molten steel is precisely controlled to flow towards the center of the web through the side outlets. The molten steel flowing from both sides meets, impacts, and mixes at predetermined positions on the web, forming a transitional web region with a composition between the two before solidification.

[0028] S300: During continuous casting, secondary cooling water is used to independently cool the first flange forming region, the second flange forming region, and the web forming region in the continuous casting mold; wherein the cooling intensity of the first flange forming region is lower than that of the second flange forming region. The secondary cooling water flow velocity in the first flange forming region is in the range of 1.8 m / s to 2.0 m / s; the secondary cooling water flow velocity in the second flange forming region is in the range of 2.4 m / s to 2.6 m / s; and the secondary cooling water flow velocity in the web forming region is in the range of 2.0 m / s to 2.2 m / s.

[0029] Then, cooling control is implemented: independent cooling is applied to the two flanges and web areas in the crystallizer and secondary cooling zone. The secondary cooling water flow rate in the first flange forming area is 1.8~2.0 m / s, the secondary cooling water flow rate in the second flange forming area is 2.4~2.6 m / s, and the secondary cooling water flow rate in the web forming area is 2.0~2.2 m / s. By adjusting the cooling water flow rate in each area, the solidification cooling rate of each area is differentially controlled to match the solidification characteristics of steels with different compositions, further optimize performance differences, ensure that the high-strength flange achieves a good combination of strength and toughness, and promote metallurgical bonding in the transition zone.

[0030] S400: After continuous casting is completed, a continuously cast billet is obtained.

[0031] S500: The continuously cast billet is heated and then rolled to obtain an H-beam with different performance flanges.

[0032] The step of heating and rolling the continuously cast billet includes the following sub-steps: S510: After heating the continuous casting billet, the continuous casting billet is rolled in 4 to 5 passes using a universal rolling mill; the rolling heating temperature is in the range of 1200°C to 1220°C.

[0033] Finally, the billet undergoes rolling: after heating, it is rolled. The rolling heating temperature is 1200°C~1220°C, and a universal rolling mill is used for 4~5 passes. During the rolling process, the strong thermomechanical deformation further diffuses and fuses the interface between the flange and the web, resulting in a more uniform composition and ultimately forming H-beams with distinct properties, smooth transitions, and strong bonding.

[0034] This application provides a double-ladle continuous casting production method for H-beams with different flange properties. This method aims to solve the problems of cumbersome procedures, susceptibility to defects, and poor interface bonding inherent in traditional welded reinforcement plate processes. This application eliminates the need for additional intermediate-composition transition steel; it uses only a first and a second ladle, each containing steel with the differentiated compositions required for high-strength and ordinary-strength flanges, respectively. The core of this method lies in employing a dual-flow composite casting nozzle with independently controllable internal cavities connected to the two ladles. Each cavity has a main outlet and a side outlet: the main outlet directly casts to form the pure-composition flange body on the corresponding side; the side outlet guides a portion of the molten steel to the central area of ​​the web in the crystallizer at a specific angle. By precisely controlling the casting speed and side-flow ratio of the two ladles, the side-flow molten steel from both sides meets, mixes, and solidifies at the center of the web, thereby forming a transitional web with compositions and properties between the two flanges in situ within the crystallizer. Combined with zoned cooling control of the crystallizer and secondary cooling zone, and subsequent rolling, H-beams with different flange properties and a smooth web transition are ultimately produced directly. This application simplifies the production process of H-beams, reduces costs, and ensures the integrity and reliability of the product structure.

[0035] This application provides a double-ladle continuous casting production method for H-beams with different flange properties, which has the following advantages: 1. Superior product performance and significantly improved structural safety: Directly achieves differentiated performance control of the two flanges, and the high-strength flange can accurately match the stress requirements such as concentrated loads and fatigue loads without the need for welded reinforcing plates; the flange and web are metallurgically bonded without mechanical connection interfaces, completely eliminating stress concentration problems and avoiding failure risks such as peeling and cracking. The transition zone has a smooth transition of components and a firm bond, significantly improving the overall structural durability and service stability.

[0036] 2. Simplified production process, improved production efficiency and yield: Eliminates the cumbersome processes of traditional welded reinforcing plates such as beveling, preheating, and post-weld heat treatment. The simultaneous casting of double ladles and subsequent rolling are completed in one integrated process, which greatly shortens the production process and reduces the complexity of the process. The casting process reduces welding defects and post-processing losses through precise flow and flow control, thereby improving production efficiency and material yield.

[0037] 3. Precise performance control to meet personalized needs: The carbon content and alloy element ratio of the double ladle steel can be flexibly adjusted according to the stress differences in actual application scenarios to achieve precise customization of high-strength flange performance; combined with the zoned independent cooling process, the solidification characteristics of steel with different compositions are matched to further optimize the performance differences between the two flanges, taking into account the strength and toughness of the high-strength flange, and adapting to the personalized design needs of fields such as construction and machinery manufacturing.

[0038] 4. Reduced overall production costs and significant economic value: On the one hand, it reduces equipment investment, labor costs, heat treatment energy consumption and auxiliary material consumption in the welding process; on the other hand, the metallurgically integrated structure reduces the cost of later maintenance and repair, and extends the service life of the product, reducing replacement losses; at the same time, the integrated production process improves capacity utilization, achieves cost reduction and efficiency improvement, and has both the potential for large-scale production and market application value.

[0039] 5. The connection at the web plate is smooth, eliminating the need for a transition steel between the two ladles.

[0040] 6. Strong process innovation and wide applicability: Based on the standard H-beam continuous casting crystallizer, the composite pouring nozzle is optimized in a targeted manner, without the need for large-scale transformation of the existing continuous casting production line. The process transformation cost is low and easy to implement. The core process can be adapted to the production of H-beams of different specifications, and the steel composition can be adjusted in a large way to meet the diverse needs of different industries for flange strength. The technology has a wide range of promotion and application.

[0041] This application provides a double-ladle continuous casting production method for H-beams with different flange properties, with the following embodiments: Example 1: 1. Steel preparation: First ladle (for high-strength flanges): C: 0.25%, Cr: 1.0%, Ni: 0.65%, Si: 0.4%, Mn: 1.2%, P≤0.03%, S≤0.03%; Second ladle (for ordinary strength flanges): C: 0.16%, Cr: 0.45%, Ni: 0.3%, Si: 0.35%, Mn: 1.0%, P≤0.03%, S≤0.03%.

[0042] 2. Casting Control: A dual-flow composite nozzle is used. Approximately 85% of the total flow from the first ladle is controlled to fill its corresponding flange through the main outlet, and approximately 15% is directed towards the web center through a side outlet (approximately 30° inclination). Similarly, approximately 80% of the total flow from the second ladle is controlled to fill its corresponding flange through the main outlet, and approximately 20% is directed towards the web center through a side outlet (approximately 30° inclination). The side flows from both ladles meet and mix near the web centerline. The total casting speed is maintained at 1.0 m / min.

[0043] 3. Cooling control: The copper plate and secondary cooling zone of the crystallizer are cooled in separate zones. The cooling water flow rate in the first flange forming zone (high strength zone) is 1.8 m / s (cooling rate approximately 25°C / min), the cooling water flow rate in the second flange forming zone (normal strength zone) is 2.5 m / s (cooling rate approximately 35°C / min), and the cooling water flow rate in the web mixing zone is 2.0 m / s (cooling rate approximately 30°C / min).

[0044] 4. Subsequent rolling: The continuously cast billet is heated to 1200°C and rolled in four passes on a universal rolling mill, with rolling reductions of 15%, 20%, 18%, and 12% respectively.

[0045] 5. Finished product performance: First flange yield strength 460MPa, tensile strength 580MPa, elongation after fracture 18%; Second flange yield strength 330MPa, tensile strength 470MPa, elongation after fracture 22%; Web (transition zone) yield strength approximately 375MPa, tensile strength approximately 495MPa, elongation after fracture 20%.

[0046] Example 2: 1. Steel preparation: Composition of molten steel in the first ladle: C: 0.28%, Cr: 1.1%, Ni: 0.75%, Si: 0.42%, Mn: 1.3%, P≤0.03%, S≤0.03%; Composition of molten steel in the second ladle: C: 0.18%, Cr: 0.55%, Ni: 0.38%, Si: 0.36%, Mn: 1.1%, P≤0.03%, S≤0.03%.

[0047] 2. Pouring Control: Adjust the sideflow ratio and angle to optimize mixing. Control the sideflow ratio of the first ladle to 12% (tilt angle 28°) and the sideflow ratio of the second ladle to 18% (tilt angle 32°). The total pouring speed is 0.9 m / min.

[0048] 3. Cooling control: The cooling water flow rate in the first flange forming area is 1.9 m / s (cooling rate is about 23°C / min), the cooling water flow rate in the second flange forming area is 2.6 m / s (cooling rate is about 38°C / min), and the cooling water flow rate in the web area is 2.1 m / s (cooling rate is about 32°C / min).

[0049] 4. Subsequent rolling: The continuously cast billet is heated to 1220℃ and rolled in 5 passes by a universal rolling mill, with rolling reductions of 12%, 18%, 22%, 16%, and 10% respectively.

[0050] 5. Finished product performance: First flange yield strength 490MPa, tensile strength 610MPa, elongation after fracture 17%; Second flange yield strength 345MPa, tensile strength 490MPa, elongation after fracture 21%; Web (transition zone) yield strength approximately 400MPa, tensile strength approximately 525MPa, elongation after fracture 19%.

[0051] A second aspect of this application provides an H-beam, comprising: The H-beam with different properties is produced by the double-ladle continuous casting production method of H-beams described in any of the above embodiments; the H-beam includes a first flange, a second flange and a web; the yield strength of the first flange is greater than the yield strength of the second flange; the chemical composition and mechanical properties of the web are between those of the first flange and the second flange.

[0052] It is worth noting that the effects of the above-mentioned H-beam application can be found in the effects of the above-mentioned method embodiments, and will not be repeated here.

[0053] The above detailed embodiments further illustrate the purpose, technical solution, and beneficial effects of the embodiments of this application. It should be understood that the above are merely specific embodiments of the embodiments of this application and are not intended to limit the protection scope of the embodiments of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solutions of the embodiments of this application should be included within the protection scope of the embodiments of this application.

Claims

1. A method for producing H-beams using double-ladle continuous casting, characterized in that, include: Prepare the first and second molten steels for the first and second ladles respectively; The first molten steel is continuously cast and rolled in the first ladle to form the first flange, and the second molten steel is continuously cast and rolled in the second ladle to form the second flange; the yield strength of the first flange is higher than that of the second flange. The first ladle and the second ladle are connected to the continuous casting mold through a dual-flow composite pouring nozzle, so that the first molten steel and the second molten steel are injected into the continuous casting mold through the dual-flow composite pouring nozzle; the dual-flow composite pouring nozzle is provided with a first inner cavity and a second inner cavity, which are respectively used to guide the molten steel of the first ladle and the second ladle; the first inner cavity is provided with a first main outlet and a first side outlet, and the second inner cavity is provided with a second main outlet and a second side outlet; The first main outlet is connected to the first flange forming area in the continuous casting mold, the second main outlet is connected to the second flange forming area in the continuous casting mold, and the first side outlet and the second side outlet are connected to the web forming area in the continuous casting mold. During continuous casting, secondary cooling water is used to perform independent cooling treatment on the continuous casting crystallizer corresponding to the first flange forming area, the second flange forming area and the web forming area. After continuous casting is completed, a continuously cast billet is obtained; The continuously cast billet is heated and then rolled to obtain an H-beam with different performance flanges.

2. The method for producing H-beams using double-ladle continuous casting according to claim 1, characterized in that, The first molten steel and the second molten steel have different carbon contents and alloy element ratios.

3. The method for producing H-beams using double-ladle continuous casting according to claim 1, characterized in that, The step of injecting the first molten steel and the second molten steel into the continuous casting mold through the dual-flow composite gating nozzle includes: The first molten steel, ranging from 65% to 75% by weight, is injected into the first flange forming area of ​​the continuous casting mold through the first main outlet; the first molten steel, ranging from 25% to 35% by weight, is injected into the web forming area of ​​the continuous casting mold through the first side outlet. In addition, 65% to 75% by weight of the second molten steel is injected into the second flange forming region of the continuous casting mold through the second main outlet; and 25% to 35% by weight of the second molten steel is injected into the web forming region of the continuous casting mold through the second side outlet.

4. The method for producing H-beams using double-ladle continuous casting according to claim 1, characterized in that, The angle between the center lines of the first and second side outlets of the dual-flow composite injection nozzle and the vertical direction is within the range of 25° to 35°.

5. The method for producing H-beams using double-ladle continuous casting according to claim 1, characterized in that, The cooling intensity of the first flange forming region is lower than that of the second flange forming region.

6. The method for producing H-beams using double-ladle continuous casting according to claim 1, characterized in that, The secondary cooling water flow velocity in the first flange forming region is in the range of 1.8 m / s to 2.0 m / s; the secondary cooling water flow velocity in the second flange forming region is in the range of 2.4 m / s to 2.6 m / s; and the secondary cooling water flow velocity in the web forming region is in the range of 2.0 m / s to 2.2 m / s.

7. The method for producing H-beams using double-ladle continuous casting according to claim 1, characterized in that, The step of heating and rolling the continuously cast billet includes: After heating the continuously cast billet, it is rolled in 4 to 5 passes using a universal rolling mill; the rolling heating temperature is in the range of 1200°C to 1220°C.

8. An H-beam, characterized in that, include: The H-beam with different properties is produced by the double-ladle continuous casting production method of H-beams according to any one of claims 1 to 7; the H-beam includes a first flange, a second flange and a web; the yield strength of the first flange is greater than the yield strength of the second flange; the chemical composition and mechanical properties of the web are between those of the first flange and the second flange.

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