A process for improving the self-flow rate of molten steel in ladle pouring

Abstract

The present invention discloses a process for improving the self-flow rate of molten steel in a ladle, which belongs to the field of metallurgy technology. The process comprises: firstly, increasing the volume of the upper nozzle in the ladle nozzle seat brick, the height sum of the upper opening and the upper straight channel in the upper nozzle is 225-245 mm, the diameter of the top of the upper opening is 210-220 mm; the height of the upper straight channel is 60-70 mm, the diameter of the upper straight channel is 90-95 mm, and the diameter of the lower straight channel is 60 mm; secondly, optimizing the masonry of the ladle nozzle seat brick, and installing the ladle nozzle seat brick. Clean the foundation plate; install the ladle nozzle seat bricks on the ladle nozzle foundation plate, and find the masonry horizontal line 30-50mm away from the ladle nozzle seat bricks; using the horizontal line as a reference, lay the non-impact area bricks and the impact area bricks in sequence, and lay them to the permanent layer of the ladle wall; after the ladle bottom bricks are laid, pack them tightly; fill the gap between the ladle nozzle seat bricks and the ladle bottom bricks with castables and tamp them firmly; fill the gap between the ladle bottom bricks and the ladle wall with castables and tamp them firmly. The process is simple and easy to implement, and effectively improves the self-flow rate of molten steel.

Description

Technical Field

[0001] The invention relates to a process for pouring molten steel, in particular to a process for improving the self-flow rate of molten steel pouring in a ladle, and belongs to the technical field of metallurgy. Background Art

[0002] With increasingly fierce competition in the steel market, higher demands are being placed on companies' product quality. One process that impacts molten steel quality is the self-flow of molten steel from the ladle, i.e., the automatic pouring of molten steel during continuous casting. If the molten steel doesn't pour automatically during continuous casting, oxygen burning at the nozzle must be performed. This operation increases the oxygen content in the steel, leading to an increase in inclusions, affecting the quality of the ingots. In severe cases, it can even cause the continuous casting machine to stop pouring, disrupting production.

[0003] Currently, improvements to the refractory drainage sand used in ladle steel tapping are commonly used to control the self-flow of molten steel in ladles. For example, patent CN115502382A describes a method for increasing the self-flow rate of slab ladle steel. This method involves adding drainage sand to the ladle. By studying the mechanism of self-flow casting in the ladle, the sand's specifications are optimized, and a specialized formulation is employed to increase the ladle's self-flow rate, improve the automatic casting rate of the casting machine, and reduce labor intensity and oxygen consumption. This method improves the self-flow rate of steel grades, reduces secondary oxidation of molten steel, improves molten steel quality, and reduces drainage diversion losses, thereby addressing the low self-flow rate of existing slab ladle steel. However, improving the drainage sand is costly and complex.

[0004] Patent CN115592106A discloses a method for improving the self-flow rate of a continuous casting tundish during pouring, which solves the problem of low self-flow rate during pouring of the tundish, the labor-intensive manual oxygen burning and drainage, the molten steel pollution problem, the burns to the upper water inlet caused by oxygen burning and drainage, and the short service life of the tundish during pouring. However, the height of the upper opening and the upper straight channel still adopt the existing technology, resulting in a short downward impact distance, a low amount of molten steel added, and a low self-flow rate of molten steel under the same working conditions.

[0005] Therefore, developing a process for increasing the self-flow rate of molten steel in a ladle that can overcome the above defects has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology and provide a process for improving the self-flow rate of molten steel in a ladle. The process is simple and easy to implement, effectively improves the self-flow rate of molten steel, and ensures the quality of molten steel.

[0007] In order to solve the above technical problems, the present invention provides a process for improving the self-flow rate of molten steel in a ladle, which specifically comprises the following steps:

[0008] 1. The volume of the upper nozzle in the ladle nozzle seat brick increases

[0009] The ladle nozzle seat brick with a flow channel is detachably provided with an upper nozzle, which includes an upper nozzle seat brick, an upper opening, an upper straight channel, a lower opening and a lower straight channel. The upper opening and the lower opening are respectively inverted truncated cone structures, and the upper straight channel and the lower straight channel are barrel-shaped structures. The top of the upper opening is flush with the upper plane of the ladle nozzle seat brick, the lower end of the upper opening is connected to the upper straight channel, the lower end of the upper straight channel is connected to the lower opening, the lower end of the lower opening is connected to the lower straight channel, the bottom end of the lower straight channel is flush with the lower plane of the ladle nozzle seat brick, and the lower opening and the lower straight channel are located inside the upper nozzle seat brick;

[0010] The sum of the heights of the upper opening and the upper straight channel in the upper water inlet is 225-245 mm, and the diameter of the top of the upper opening is 210-220 mm;

[0011] The height of the upper straight channel is 60-70 mm, and the diameter of the upper straight channel is 90-95 mm;

[0012] The height of the lower opening is 99mm;

[0013] The height of the lower straight channel is 96mm;

[0014] The diameter of the lower straight channel is 60mm;

[0015] 2. Optimization of Ladle Nozzle Seat Brickwork

[0016] Clean the installation base plate of the ladle nozzle seat brick and adjust the base plate to be flat;

[0017] Install the ladle nozzle seat brick on the ladle nozzle foundation plate and find the masonry horizontal line 30-50mm away from the ladle nozzle seat brick;

[0018] Taking the horizontal line as the reference, lay 270mm non-impact area bricks and 350mm impact area bricks in sequence upwards until the permanent layer of the ladle wall;

[0019] After the bottom bricks are laid, the bricks should be packed tightly;

[0020] Use castables to fill and tamp the gap between the ladle nozzle seat bricks and the ladle bottom bricks; use castables to fill and tamp the gap between the ladle bottom bricks and the ladle wall.

[0021] The technical solution further defined in the present invention is:

[0022] Furthermore, in the aforementioned process for improving the self-flow rate of molten steel in the ladle, in step 1, the amount of drainage sand increased by 10 kg for every 1.2 dm³ increase in the volume of the upper water inlet in the ladle nozzle seat brick.

[0023] In the aforementioned process for improving the self-flow rate of molten steel in the ladle, when laying bricks in the non-impact area and the impact area in step 2, the brick joints are ≤1mm.

[0024] In the aforementioned process for improving the self-flow rate of molten steel in the ladle, after the ladle bottom bricks are laid in step 2, the bricks are tightly packed with triangular wedges.

[0025] In the aforementioned process for improving the self-flow rate of molten steel in the ladle, the castable in step 2 is a corundum castable.

[0026] The beneficial effects of the present invention are:

[0027] Compared with the existing structure such as Figure 1 As shown, the present invention lengthens the height of the upper opening and the upper straight channel, which is 60-80mm higher than the general one, which can increase the smoothness of the molten steel, increase the downward impact distance, and increase the speed of the steel self-flow. The height of the upper straight channel is shortened to increase the distance of the upper opening and further increase the flow rate of the self-flow; the diameter of the upper opening is expanded to facilitate the increase of the amount of molten steel added and improve efficiency; the diameter of the upper straight channel is reduced to facilitate the sudden tightening of the molten steel flow and increase the speed of the molten steel flowing downward; at the same time, the diameter of the lower opening is increased to facilitate rapid flow and feeding.

[0028] The present invention can effectively solve the problem of low molten steel flow rate under the same working conditions, thereby achieving the effect of improving the molten steel flow rate, increasing the amount of drainage sand, and increasing the molten steel flow rate by 3-5%, while also achieving obvious economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the structure of the ladle nozzle seat brick in the prior art is obtained;

[0030] Figure 2 This is a schematic diagram of the structure of the ladle nozzle seat brick in an embodiment of the present invention;

[0031] Figure 3 This is a side view of a structure obtained by brick laying of a ladle nozzle seat in an embodiment of the present invention;

[0032] Figure 4 A top view of a structure obtained by brick laying of a ladle nozzle seat in an embodiment of the present invention;

[0033] In the figure: 1- ladle nozzle seat brick, 2- upper nozzle seat brick, 3- upper opening, 4- upper straight channel, 5- lower opening, 6- lower straight channel, 7- non-impact zone brick, 8-impact zone brick. DETAILED DESCRIPTION Example 1

[0034] This embodiment provides a process for improving the self-flow rate of molten steel in a ladle, the structure of which is as follows: Figure 2-4 As shown, the specific steps include:

[0035] 1. The volume of the upper nozzle in the ladle nozzle seat brick is increased by 1.2 dm³, and the drainage sand is increased by 10 kg;

[0036] The ladle nozzle seat brick 1 with a flow channel is detachably provided with an upper nozzle, which includes an upper nozzle seat brick 2, an upper opening 3, an upper straight channel 4, a lower opening 5 and a lower straight channel 6. The upper opening 3 and the lower opening 5 are respectively inverted truncated cone structures, and the upper straight channel 4 and the lower straight channel 6 are barrel-shaped structures. The top of the upper opening 3 is flush with the upper plane of the ladle nozzle seat brick 1, the lower end of the upper opening 3 is connected to the upper straight channel 4, the lower end of the upper straight channel 4 is connected to the lower opening 5, the lower end of the lower opening 5 is connected to the lower straight channel 6, and the bottom end of the lower straight channel 6 is flush with the lower plane of the ladle nozzle seat brick 1. The lower opening 5 and the lower straight channel 6 are located in the upper nozzle seat brick 2;

[0037] Compared with existing technologies such as Figure 1 Compared with the figure, the height of the upper opening 3 and the upper straight channel 4 in the upper water inlet increases by 60mm from 165mm to 225mm, and the diameter of the top of the upper opening 3 increases by 10mm from 200mm to 210mm;

[0038] The height of the upper straight channel 4 is reduced by 55mm from 115mm to 60mm, and the diameter of the upper straight channel 4 is increased by 10mm from 80mm to 90mm;

[0039] The height of the lower opening 5 is 99 mm;

[0040] The height of the lower straight channel 6 is 96 mm;

[0041] The diameter of the lower straight channel 6 is increased by 5mm from 55mm to 60mm;

[0042] 2. Optimization of Ladle Nozzle Seat Brickwork

[0043] Clean the installation base plate of the ladle nozzle seat brick 1 and adjust the base plate to be flat;

[0044] Install the ladle nozzle seat brick 1 on the ladle nozzle base plate, and find the masonry horizontal line 30mm away from the ladle nozzle seat brick;

[0045] Based on the horizontal line, lay 270mm non-impact area bricks 7 and 350mm impact area bricks 8 in sequence upwards until they reach the permanent layer of the ladle wall, with the brick joints ≤1mm;

[0046] After the bottom bricks are laid, use triangular wedges to tighten the bricks;

[0047] Use corundum castable to fill and tamp the gap between the ladle nozzle seat brick 1 and the ladle bottom brick; use castable to fill and tamp the gap between the ladle bottom brick and the ladle wall.

[0048] When the present invention is used, under the same working conditions, the amount of drainage sand can be increased and the self-flow rate of molten steel can be increased by 3%. Example 2

[0049] This embodiment provides a process for improving the self-flow rate of molten steel in a ladle, the structure of which is as follows: Figure 2-4 As shown, the specific steps include:

[0050] 1. The volume of the upper nozzle in the ladle nozzle seat brick is increased by 1.2 dm³, and the drainage sand is increased by 10 kg;

[0051] The ladle nozzle seat brick 1 with a flow channel is detachably provided with an upper nozzle, which includes an upper nozzle seat brick 2, an upper opening 3, an upper straight channel 4, a lower opening 5 and a lower straight channel 6. The upper opening 3 and the lower opening 5 are respectively inverted truncated cone structures, and the upper straight channel 4 and the lower straight channel 6 are barrel-shaped structures. The top of the upper opening 3 is flush with the upper plane of the ladle nozzle seat brick 1, the lower end of the upper opening 3 is connected to the upper straight channel 4, the lower end of the upper straight channel 4 is connected to the lower opening 5, the lower end of the lower opening 5 is connected to the lower straight channel 6, and the bottom end of the lower straight channel 6 is flush with the lower plane of the ladle nozzle seat brick 1. The lower opening 5 and the lower straight channel 6 are located in the upper nozzle seat brick 2;

[0052] Compared with existing technologies such as Figure 1 Compared with the figure, the height of the upper opening 3 and the upper straight channel 4 in the upper water inlet increases by 80mm from 165mm to 245mm, and the diameter of the top of the upper opening 3 increases by 20mm from 200mm to 220mm;

[0053] The height of the upper straight channel 4 is reduced by 45mm from 115mm to 70mm, and the diameter of the upper straight channel 4 is increased by 15mm from 80mm to 95mm;

[0054] The height of the lower opening 5 is 99 mm;

[0055] The height of the lower straight channel 6 is 96 mm;

[0056] The diameter of the lower straight channel 6 is increased by 5mm from 55mm to 60mm;

[0057] 2. Optimization of Ladle Nozzle Seat Brickwork

[0058] Clean the installation base plate of the ladle nozzle seat brick 1 and adjust the base plate to be flat;

[0059] Install the ladle nozzle seat brick 1 on the ladle nozzle base plate, and find the masonry horizontal line at a position 50mm away from the ladle nozzle seat brick;

[0060] Based on the horizontal line, lay 270mm non-impact area bricks 7 and 350mm impact area bricks 8 in sequence upwards until they reach the permanent layer of the ladle wall, with the brick joints ≤1mm;

[0061] After the bottom bricks are laid, use triangular wedges to tighten the bricks;

[0062] Use corundum castable to fill and tamp the gap between the ladle nozzle seat brick 1 and the ladle bottom brick; use castable to fill and tamp the gap between the ladle bottom brick and the ladle wall.

[0063] When the present invention is used, under the same working conditions, the amount of drainage sand can be increased and the self-flow rate of molten steel can be increased by 5%.

[0064] In addition to the above embodiments, the present invention may also have other implementations. Any technical solution formed by equivalent replacement or equivalent transformation falls within the scope of protection required by the present invention.

Claims

1. A process for improving the self-flow rate of molten steel in a ladle, characterized in that: The specific steps include:

1. The volume of the upper nozzle in the ladle nozzle seat brick increases A ladle nozzle seat brick (1) with a flow channel is provided with a detachable upper nozzle, the upper nozzle comprising an upper nozzle seat brick (2), an upper opening (3), an upper straight channel (4), a lower opening (5) and a lower straight channel (6), the upper opening (3) and the lower opening (5) are respectively inverted truncated cone structures, the upper straight channel (4) and the lower straight channel (6) are barrel-shaped structures, the top of the upper opening (3) is flush with the upper plane of the ladle nozzle seat brick (1), the lower end of the upper opening (3) is connected to the upper straight channel (4), the lower end of the upper straight channel (4) is connected to the lower opening (5), the lower end of the lower opening (5) is connected to the lower straight channel (6), the bottom end of the lower straight channel (6) is flush with the lower plane of the ladle nozzle seat brick (1), and the lower opening (5) and the lower straight channel (6) are located in the upper nozzle seat brick (2); The sum of the heights of the upper opening (3) and the upper straight channel (4) in the upper water inlet is 225-245 mm, and the diameter of the top end of the upper opening (3) is 210-220 mm; The height of the upper straight channel (4) is 60-70 mm, and the diameter of the upper straight channel (4) is 90-95 mm; The height of the lower opening (5) is 99 mm; The height of the lower straight channel (6) is 96 mm; The diameter of the lower straight channel (6) is 60 mm; 2. Optimization of Ladle Nozzle Seat Brickwork Clean the installation base plate of the ladle nozzle seat brick (1) and adjust the base plate to be flat; Install the ladle nozzle base brick (1) on the ladle nozzle base plate, and find the masonry horizontal line at a distance of 30-50 mm from the ladle nozzle base brick; Taking the horizontal line as a reference, 270mm non-impact area bricks (7) and 350mm impact area bricks (8) are laid upwards in sequence until they reach the permanent layer of the ladle wall; After the bottom bricks are laid, the bricks should be packed tightly; The gap between the ladle nozzle seat brick (1) and the ladle bottom brick is filled and compacted with castable material; the gap between the ladle bottom brick and the ladle wall is filled and compacted with castable material.

2. The process for improving the self-flow rate of molten steel in a ladle according to claim 1, wherein: In the step 1, for every 1.2 dm³ increase in the volume of the upper nozzle in the ladle nozzle seat brick, the amount of drainage sand increased by 10 kg.

3. The process for improving the self-flow rate of molten steel in a ladle according to claim 1, wherein: When laying bricks in the non-impact area and the impact area in step 2, the brick joints are ≤1mm.

4. The process for improving the self-flow rate of molten steel in a ladle according to claim 1, wherein: After the bottom bricks are laid in step 2, the bricks are tightly packed with triangular wedges.

5. The process for improving the self-flow rate of molten steel in a ladle according to claim 1, wherein: The castable in step 2 is corundum castable.

Images