Steel ladle

Abstract

The invention relates to a steel ladle which comprises a steel shell, a permanent pouring layer located above the bottom of the steel shell, steel ladle bottom refractory prefabricated bricks which are located above the permanent pouring layer and used for resisting molten steel scouring, and a working pouring material layer which is located above the permanent pouring material layer and surrounds the steel ladle bottom refractory prefabricated bricks. The steel ladle bottom refractory prefabricated brick is characterized in that the steel ladle bottom refractory prefabricated brick comprises a working layer prefabricated brick making contact with molten steel and further comprises a safety layer prefabricated brick which is nested at the bottom of the working layer prefabricated brick and has a T-shaped section, and a net-shaped steel structure is arranged on the plane, 0-30 mm away from the upper surface of the safety layer prefabricated brick, of the safety layer prefabricated brick.

Description

Technical Field

[0001] The present invention relates to equipment for steel production, and more particularly to a ladle. Background Art

[0002] There is a height difference of about 7 meters between the steel outlet of the converter and the bottom of the ladle. The impact zone at the bottom of the ladle is the part most severely eroded by molten steel. It has to withstand the impact of molten steel at a temperature of about 1650°C coming out of the converter. As the ladle is used more times, the thickness of the refractory material in the impact zone gradually decreases, and the safety risk will gradually increase.

[0003] At present, the ladle is usually as attached Figure 1 As shown, it includes a steel shell 1, a permanent casting layer 2 located above the bottom of the steel shell, a prefabricated refractory brick 3 of the ladle bottom that resists erosion of molten steel located above the permanent casting layer, and a working casting layer 4 located above the permanent casting layer and surrounding the prefabricated refractory brick of the ladle bottom. The prefabricated refractory brick 3 of the ladle bottom is usually made of a whole prefabricated refractory plate, which will become thinner and thinner with the erosion and melting of molten steel, and even cause the impact area to seep and leak molten steel, thereby causing the entire ladle to be scrapped. To prevent such accidents, after each steel casting, the ladle will be hoisted to the hot repair platform to let the ladle lie flat. The hot repair personnel will check the use of the refractory in the ladle to determine whether the refractory can continue to be used, or whether it can be taken offline and hoisted to the cold repair platform for maintenance. Since an integral prefabricated refractory plate is installed in the impact area at the bottom of the ladle, the lower part of the prefabricated plate in the impact area is connected to the permanent layer of the ladle. During the use of the ladle, the prefabricated plate is gradually melted and the thickness of the refractory is thinning. As there are no obvious warning signs in the integral precast panels, the ladle judges are unable to accurately determine the remaining thickness of the refractory precast bricks in the impact zone at the bottom of the ladle. They rely entirely on experience, and sometimes misjudgment is inevitable, which can cause molten steel to seep or leak in the impact zone during the use of the ladle, and even cause the entire ladle to be scrapped.

[0004] Therefore, how to accurately and timely discover the risks caused by the thinning of refractory materials due to scouring and melting loss in the impact zone of the ladle bottom, and how to avoid seepage and leakage of molten steel in the impact zone of the ladle bottom is a major issue in ladle steelmaking. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a ladle, and the technical solution it adopts is: a ladle, which includes a steel shell, a permanent casting layer located above the bottom of the steel shell, precast refractory bricks of the ladle bottom located above the permanent casting layer to resist the scouring of molten steel, and a working casting layer located above the permanent casting layer and surrounding the precast refractory bricks of the ladle bottom, characterized in that: the precast refractory bricks of the ladle bottom include working layer precast bricks in contact with the molten steel, and also include safety layer precast bricks with a T-shaped cross-section nested in the bottom of the working layer precast bricks, wherein the safety layer precast bricks are provided with a mesh steel structure on a plane 0-30 mm away from the upper surface thereof.

[0006] A further technical feature of the present invention is: The height of the prefabricated bricks of the safety layer is 90-120 mm.

[0007] The mesh steel structure is a 100*100mm mesh steel structure welded from steel bars with a diameter of 6-10mm.

[0008] The periphery of the precast bricks of the working layer is in a staggered concave-convex design or a stepped design or a combination of the two designs from top to bottom.

[0009] When the safety layer precast bricks are provided with a mesh steel structure on a plane 0-20 mm away from their upper surface, at least 4 T-shaped rivet nails connected to the working layer precast bricks are evenly arranged on the nodes of the mesh steel structure in the upward direction, and at least 4 T-shaped rivet nails connected to the safety layer precast bricks are also evenly arranged on the nodes of the mesh steel structure in the downward direction.

[0010] The T-shaped rivet nail is welded from steel bars with a diameter of 4-6 mm, and the height of the T-shaped rivet nail is 30-70 mm.

[0011] The height of the T-shaped rivet nail is 30 mm, 40 mm, 50 mm, 60 mm or 70 mm.

[0012] When the safety layer precast bricks are provided with a mesh steel structure on a plane 20-30 mm away from the upper surface thereof, at least 4 T-shaped rivet nails connected to the working layer precast bricks are evenly arranged on the nodes of the mesh steel structure in an upward direction.

[0013] The T-shaped rivet nail is welded from steel bars with a diameter of 4-6 mm, and the height of the T-shaped rivet nail is 30-70 mm.

[0014] The height of the T-shaped rivet nail is 30 mm, 40 mm, 50 mm, 60 mm or 70 mm.

[0015] The beneficial effects of the present invention are: Since the ladle described in the present invention has precast refractory bricks at the bottom of the ladle including precast working layer bricks in contact with molten steel, and also includes precast safety layer bricks with a T-shaped cross-section nested in the bottom of the precast working layer bricks, wherein the precast safety layer bricks are provided with a mesh steel structure on a plane 0-30 mm away from the upper surface thereof, when the refractory structure at the bottom of the ladle is melted to the mesh steel structure, because the steel and refractory materials present two different brightnesses at high temperatures, it can serve as a good warning for the ladle judges, and even if the steel structure is melted, a 6-10 mm groove will be formed on the refractory surface, and the brightness of the groove at high temperature will be different from that of the surrounding refractory materials, and will be brighter than the refractory materials. In this way, the ladle judges can also judge the condition of the refractory structure at the bottom of the ladle more intuitively, conveniently and quickly. When the refractory structure at the bottom of the ladle is melted to the mesh steel structure, it is equivalent to drawing a warning line, which is conducive to the ladle judges to judge the condition of the refractory material at the bottom of the ladle more intuitively, conveniently and quickly, and can ensure safer operation of the ladle. Since the prefabricated bricks of the safety layer below the grid-like steel structure are about 100mm thick, the impact zone will not immediately seep or leak molten steel. The ladle judge can promptly arrange maintenance personnel to take the ladle offline for maintenance, which can ensure the ladle's safer operation and effectively extend its service life.

[0016] In addition, due to thermal shock problems, longitudinal cracks are very likely to occur in the working layer precast bricks of the ladle bottom refractory precast bricks. When the cracks extend to the safety layer precast bricks, since the safety layer precast bricks and the working layer precast bricks are cast twice, there are joints on the interface. The cracks are blocked by the joints at the interface between the working layer precast bricks and the safety layer precast bricks and will not continue to extend downward, thus preventing the molten steel from directly penetrating into the permanent layer of the ladle bottom and improving the safety factor of the ladle bottom. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural cross-sectional view of an existing ladle; Figure 2 is a structural cross-sectional view of an embodiment of the present invention; Figure 3 yes Figure 2 A magnified view of the structure of the precast refractory bricks at the bottom of the ladle; Figure 4 yes Figure 3 Structural stereogram of the middle mesh steel structure and T-shaped rivets; Figure 5 is a structural cross-sectional view of another embodiment of the present invention; Figure 6 yes Figure 5 A magnified view of the structure of the precast refractory bricks at the bottom of the ladle; Figure 7 yes Figure 6 Structural stereogram of the central mesh steel structure and T-shaped rivets. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below with reference to the accompanying drawings.

[0019] Example 1, reference Figures 2 to 4 A ladle comprises a steel shell 1, a permanent casting layer 2 located above the bottom of the steel shell, precast refractory bricks 3 for the ladle bottom resistant to erosion by molten steel located above the permanent casting layer, and a working casting layer 4 located above the permanent casting layer and surrounding the precast refractory bricks for the ladle bottom, wherein the precast refractory bricks 3 for the ladle bottom comprise working layer precast bricks 31 in contact with the molten steel, and also comprise safety layer precast bricks 32 with a T-shaped cross-section nested in the bottom of the working layer precast bricks, wherein the safety layer precast bricks are provided with a mesh steel structure 33 on a plane 20-30 mm away from the upper surface thereof.

[0020] In this embodiment, the height of the safety layer precast bricks 32 is 90-120 mm; the mesh steel structure 33 is a 100*100 mm mesh steel structure welded by steel bars with a diameter of 6-10 mm; in order to strengthen the connection stability between the safety layer precast bricks 32 and the working layer precast bricks 31, 4 T-shaped rivet nails 34 connected to the working layer precast bricks 31 are evenly arranged on the nodes of the mesh steel structure 33 in the upward direction, and the T-shaped rivet nails are welded by steel bars with a diameter of 4-6 mm, and the height of the T-shaped rivet nails is 30-70 mm; the steel bars used in the mesh steel structure 33 are thicker in diameter, and the safety warning is more obvious. The steel bars used in the T-shaped rivet nails 34 are thinner in diameter, and the thermal expansion is small, which will not affect the refractory material.

[0021] In addition, in this embodiment, the periphery of the working layer precast bricks 31 is designed in a step-like shape from top to bottom, so that when used, they can be engaged with the working castable layer 4 in the non-impact area and are not easy to fall off.

[0022] Example 2, reference Figure 5-Figure 7 In this embodiment, the safety layer precast bricks are provided with a mesh steel structure on a plane 0-20mm away from the upper surface thereof. The mesh steel structure is a 100*100mm mesh steel structure welded by steel bars with a diameter of 6-10mm; in order to strengthen the connection stability between the safety layer precast bricks and the working layer precast bricks, 4 T-shaped rivet nails connected to the working layer precast bricks are evenly arranged on the nodes of the mesh steel structure in the upward direction, and 4 T-shaped rivet nails connected to the safety layer precast bricks are evenly arranged on the nodes of the mesh steel structure in the downward direction; in addition, in this embodiment, the periphery of the working layer precast bricks 31 is staggered from top to bottom in a concave-convex design, so that when used, it can bite with the working castable layer 4 in the non-impact area and is not easy to fall off. The other structures are the same as those in Example 1.

[0023] In practical applications, the number of T-shaped rivets evenly arranged on the nodes of the mesh steel structure and connected to the precast bricks of the working layer can also be 5, 6, 7, 8 or even more, and the height of the T-shaped rivets is 30 mm, 40 mm, 50 mm, 60 mm or 70 mm. The periphery of the precast bricks 31 of the working layer can also be a combination of a concave-convex staggered design and a stepped design from top to bottom.

[0024] Since the precast refractory bricks 3 at the bottom of the ladle described in the present invention include working layer precast bricks 31 in contact with the molten steel, and also include safety layer precast bricks 32 with a T-shaped cross-section nested in the bottom of the working layer precast bricks, wherein the safety layer precast bricks are provided with a mesh steel structure 33 on a plane 0-30 mm away from the upper surface thereof, when the refractory structure at the bottom of the ladle is melted to the mesh steel structure 33, because the steel and refractory materials present two different brightnesses at high temperatures, it can serve as a good warning for the ladle judges. Even if the steel structure is melted, a 6-10 mm groove will be formed on the refractory surface. The brightness of the groove at high temperature will be different from that of the surrounding refractory materials, and will be brighter than the refractory materials. In this way, the ladle judges can also judge the condition of the refractory structure at the bottom of the ladle more intuitively, conveniently and quickly. When the refractory structure at the bottom of the ladle is melted to the mesh steel structure, it is equivalent to drawing a warning line, which is conducive to the ladle judges to judge the condition of the refractory material at the bottom of the ladle more intuitively, conveniently and quickly, and can ensure safer operation of the ladle. Since the prefabricated bricks of the safety layer below the grid-like steel structure 33 are still about 100 mm thick, the impact zone will not immediately seep or leak molten steel. The ladle judge can promptly arrange maintenance personnel to take the ladle offline for maintenance, which can ensure safer operation of the ladle and effectively extend the service life of the ladle.

[0025] In addition, due to thermal shock problems, longitudinal cracks are very likely to occur in the working layer precast bricks 3 of the ladle bottom refractory precast bricks 3. When the cracks extend to the safety layer precast bricks 32, since the safety layer precast bricks 32 and the working layer precast bricks 31 are cast twice and there are joints at the interface, the cracks are blocked by the joints at the interface between the working layer precast bricks 31 and the safety layer precast bricks 32 and will not continue to extend downward, thereby preventing the molten steel from directly penetrating into the permanent layer of the ladle bottom and improving the safety factor of the ladle bottom.

[0026] The technical content and technical features of the present invention have been disclosed above, but it is understood that under the creative ideas of the present invention, those skilled in the art can make various changes and improvements to the above structure, including the combination of technical features disclosed or claimed separately here, and other combinations that obviously include these features. These variations and / or combinations all fall within the technical field involved in the present invention and fall within the protection scope of the claims of the present invention.

Claims

1. A ladle, comprising a steel shell, a permanent casting layer located above the bottom of the steel shell, prefabricated refractory bricks of the ladle bottom for resisting erosion of molten steel located above the permanent casting layer, and a working casting layer located above the permanent casting layer and surrounding the prefabricated refractory bricks of the ladle bottom, characterized in that: The refractory precast bricks at the bottom of the ladle include working layer precast bricks in contact with molten steel, and also include safety layer precast bricks with a T-shaped cross-section nested in the bottom of the working layer precast bricks, wherein the safety layer precast bricks are provided with a mesh steel structure on a plane 0-30mm away from the upper surface thereof.

2. The ladle according to claim 1, characterized in that: The height of the prefabricated bricks of the safety layer is 90-120 mm.

3. The ladle according to claim 1, characterized in that: The mesh steel structure is a 100*100mm mesh steel structure welded from steel bars with a diameter of 6-10mm.

4. The ladle bottom refractory structure according to claim 1, characterized in that: The periphery of the precast bricks of the working layer is in a staggered concave-convex design or a stepped design or a combination of the two designs from top to bottom.

5. The ladle according to claim 1 or claim 2 or claim 3 or claim 4, characterized in that: When the safety layer precast bricks are provided with a mesh steel structure on a plane 0-20 mm away from their upper surface, at least 4 T-shaped rivet nails connected to the working layer precast bricks are evenly arranged on the nodes of the mesh steel structure in the upward direction, and at least 4 T-shaped rivet nails connected to the safety layer precast bricks are also evenly arranged on the nodes of the mesh steel structure in the downward direction.

6. The ladle according to claim 5, characterized in that: The T-shaped rivet nail is welded from steel bars with a diameter of 4-6 mm, and the height of the T-shaped rivet nail is 30-70 mm.

7. The ladle bottom refractory structure according to claim 6, characterized in that: The height of the T-shaped rivet nail is 30mm, 40mm, 50mm, 60mm or 70mm.

8. The ladle according to claim 1 or claim 2 or claim 3 or claim 4, characterized in that: When the safety layer precast bricks are provided with a mesh steel structure on a plane 20-30 mm away from the upper surface thereof, at least 4 T-shaped rivet nails connected to the working layer precast bricks are evenly arranged on the nodes of the mesh steel structure in an upward direction.

9. The ladle according to claim 8, characterized in that: The T-shaped rivet nail is welded from steel bars with a diameter of 4-6 mm, and the height of the T-shaped rivet nail is 30-70 mm.

10. The ladle according to claim 9, characterized in that: The height of the T-shaped rivet nail is 30 mm, 40 mm, 50 mm, 60 mm or 70 mm.

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