Steel ladle bottom refractory material structure

Abstract

The invention relates to a steel ladle bottom refractory material structure which comprises a permanent castable layer located at the bottom of a steel ladle, steel ladle bottom refractory material prefabricated bricks located above the permanent castable layer and making contact with molten steel, and a working castable layer surrounding the steel ladle bottom refractory material 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 a ladle refractory structure, and more particularly to a ladle bottom refractory structure. 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 refractory structure of ladle bottom is as follows Figure 1 As shown, it usually includes a permanent casting material layer 1 located at the bottom of the ladle, a prefabricated refractory brick 3 of the ladle bottom in contact with the molten steel located above the permanent casting material layer, and a working casting material layer 2 surrounding the prefabricated refractory brick of the ladle bottom. The prefabricated refractory brick 3 of the ladle bottom usually adopts a whole piece of prefabricated refractory plate, which will become thinner and thinner with the scouring and melting of the 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 from happening, 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, and 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 brought about by the thinning of refractory materials due to scouring and melting of precast refractory bricks 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 refractory structure for the bottom of a ladle, and the technical solution it adopts is: a refractory structure for the bottom of a ladle, which includes a permanent castable layer located at the bottom of the ladle, precast refractory bricks for the bottom of the ladle located above the permanent castable layer and in contact with the molten steel, and a working castable layer surrounding the precast refractory bricks for the bottom of the ladle, characterized in that the precast refractory bricks for the bottom of the ladle 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 mesh steel structure is a 100*100mm mesh steel structure welded from steel bars with a diameter of 6-10mm.

[0007] 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.

[0008] The height of the prefabricated bricks of the safety layer is 90-120 mm.

[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 precast refractory bricks at the bottom of the ladle in the present invention include precast working layer bricks in contact with the molten steel, and also include precast safety layer bricks with a T-shaped cross-section nested at 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 precast bricks of the working layer in the refractory structure of the ladle bottom. When the cracks extend to the precast bricks of the safety layer, since the precast bricks of the safety layer and the precast bricks of the working layer are cast twice, there are joints at the interface. The cracks are blocked by the joints at the interface between the precast bricks of the working layer and the precast bricks of the safety layer 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 cross-sectional view of the existing ladle bottom refractory structure; 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 refractory structure for the bottom of a ladle, comprising a permanent castable layer 1 located at the bottom of the ladle, precast refractory bricks 3 for the bottom of the ladle located above the permanent castable layer and in contact with molten steel, and a working castable layer 2 surrounding the precast refractory bricks for the bottom of the ladle, wherein the precast refractory bricks for the bottom of the ladle 3 comprise working layer precast bricks 31 in contact with 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 mesh steel structure is a 100*100mm mesh steel structure welded from steel bars with a diameter of 6-10mm; in order to strengthen the connection stability between the precast bricks of the safety layer and the precast bricks of the working layer, 4 T-shaped rivets 34 connected to the precast bricks of the working layer are evenly arranged on the nodes of the mesh steel structure 33, and the T-shaped rivets are welded from steel bars with a diameter of 4-6mm, and the height of the T-shaped rivets is 30-70 mm; the steel bars used in the mesh steel structure are thicker in diameter, and the safety warning is more obvious, and the steel bars used in the T-shaped rivets 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 height of the safety layer precast bricks 32 is 90-120 mm; the periphery of the working layer precast bricks 31 is designed in a step-like shape from top to bottom, so that when used, it can be engaged with the working castable layer 2 in the non-impact area and is not easy to fall off.

[0022] In practical applications, the periphery of the working layer precast bricks 31 can be designed in a staggered concave-convex shape from top to bottom, or a combination of a stepped design and a staggered concave-convex shape, so that the working castable layer 2 in the non-impact area can be bitten during application and is not easy to fall off.

[0023] In practical applications, the number of T-shaped rivets evenly arranged on the nodes of the mesh steel structure and connected to the prefabricated bricks of the working layer can also be 5, 6, 7, 8 or even more; the height of the T-shaped rivets 34 is 30 mm, 40 mm, 50 mm, 60 mm or 70 mm.

[0024] Example 2, reference Figures 5 to 7In this embodiment, the safety layer precast brick 32 is provided with a mesh steel structure 33 on a plane 0-20 mm away from its upper surface. The mesh steel structure 33 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 brick 32 and the working layer precast brick 31, 4 T-shaped rivet nails 34 connected to the working layer precast brick 31 are evenly arranged on the nodes of the mesh steel structure 33 in the upward direction, and 4 T-shaped rivet nails 34 connected to the safety layer precast brick 32 are also evenly arranged on the nodes of the mesh steel structure 33 in the downward direction; the periphery of the working layer precast brick 31 is designed in a staggered shape from top to bottom, so that it can bite with the working castable layer 2 in the non-impact area during application and is not easy to fall off; other structures are the same as those in Example 1.

[0025] In practical applications, the number of T-shaped rivets uniformly arranged in the upward and downward directions on the nodes of the mesh steel structure 33 may also be 5, 6, 7, 8 or even more.

[0026] Since the precast refractory bricks 3 at the bottom of the ladle 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 31, 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 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.

[0027] In addition, due to thermal shock problems, longitudinal cracks are very likely to occur in the working layer precast bricks 31 in the refractory structure of the ladle bottom. 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 seams at the interface, the cracks are blocked by the seams 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.

[0028] 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 bottom refractory structure, comprising a permanent castable layer located at the bottom of the ladle, a ladle bottom refractory prefabricated brick located above the permanent castable layer and in contact with molten steel, and a working castable layer surrounding the ladle bottom refractory prefabricated brick, 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 bottom refractory structure 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.

3. 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.

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

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

Images