A method for adding sand to ladle drainage sand

Abstract

The present invention provides a ladle drainage sand adding method, comprising the following steps: rough sand adding: adding drainage sand to the inside of the ladle nozzle until the height of the drainage sand is higher than the upper surface of the nozzle; surface leveling: oscillating the drainage sand so that the drainage sand is evenly distributed and the upper surface of the drainage sand coincides with the upper surface of the nozzle; spiral sand adding: spirally moving a funnel conduit to add drainage sand to the nozzle surface; model scanning: using a 3D scanner and model scanning software to scan the drainage sand on the upper surface of the nozzle to obtain the upper surface shape of the drainage sand; shape trimming: using a conduit to accurately add sand to defective locations based on the scanned shape, so that the final upper surface shape of the drainage sand is partially spherical. The present invention can scan the drainage sand shape during the sand adding process, perform shape fitting based on the shape, obtain the defective location, and perform precise sand adding, ultimately obtaining a mushroom-shaped filling state with an upwardly convex arc upper surface shape in the cross-sectional view of the drainage sand, thereby improving the automatic pouring rate of the ladle.

Description

Technical Field

[0001] The invention belongs to the field of steel smelting, and in particular relates to a ladle drainage sand adding method. Background Art

[0002] Ladle drainage sand is filled in the ladle base bricks to isolate the molten steel from the slide and protect the slide. The drainage sand on top of the base bricks begins to sinter under the high temperature of the molten steel. When the slide is opened, the loose drainage sand at the bottom automatically flows out, and the sintered layer on top breaks apart under the static pressure of the molten steel, allowing the molten steel to flow out. This process is known as automatic ladle pouring. In actual production, automatic ladle pouring often fails, forcing steel companies to resort to oxygen burning to remove the clogged drainage sand. In reality, this oxygen burning process not only seriously degrades the cleanliness of the molten steel, but also poses safety risks and reduces production efficiency.

[0003] Therefore, all steel companies attach great importance to improving the automatic pouring rate of the ladle, and set a 100% automatic pouring rate as the ultimate goal. Among the factors affecting the automatic pouring rate, the shape of the drainage sand is also an important factor. When filling drainage sand, there are generally three stacking states: ideal mushroom shape, insufficient addition, and incomplete nozzle filling. Production practice has proved that the mushroom-shaped filling state can effectively improve the automatic pouring rate of the ladle. In the process of adding drainage sand, in order to control the drainage sand to form an ideal mushroom shape, it is often necessary to rely on the experience of the staff and it is easily affected by other factors. Therefore, there is a need for a drainage sand adding method that can form an ideal mushroom shape. Summary of the Invention

[0004] In response to the above technical problems, one of the purposes of one embodiment of the present invention is to provide a method for adding sand to a ladle drainage sand, which adopts a two-time sand adding method. The first sand adding is for rough sand adding to ensure that the amount added is sufficient. During the second sand adding process, the shape of the drainage sand is scanned, and the shape is fitted to obtain the defect position, and sand is added accurately, and the scanning is continued until the upper surface shape of the drainage sand cross-sectional view is finally obtained as a mushroom-shaped filling state with an upward convex arc, thereby improving the automatic pouring rate of the ladle.

[0005] Note that the inclusion of these objectives does not preclude the existence of other objectives. One embodiment of the present invention does not necessarily achieve all of the above objectives. Objectives other than the above objectives may be extracted from the description of the specification, drawings, and claims.

[0006] The present invention achieves the above technical objectives through the following technical means.

[0007] A ladle drainage sand adding method comprises the following steps:

[0008] Step S1, roughly adding sand: closing the bottom of the ladle nozzle, using a funnel guide to add drainage sand into the ladle nozzle until the height of the drainage sand is higher than the upper surface of the nozzle;

[0009] Step S2, surface leveling: oscillating the drainage sand to make it evenly distributed, using a scraper to scrape off excess drainage sand from the upper surface of the nozzle so that the upper surface of the drainage sand coincides with the upper surface of the nozzle, and using a vacuum cleaner to suck away the scraped drainage sand;

[0010] Step S3, spiral sand adding: spirally moving the funnel guide tube to add drainage sand to the upper surface of the water inlet, and making the center of the upper surface of the drainage sand convex;

[0011] Step S4, model scanning: using a 3D scanner and model scanning software to scan the drainage sand on the upper surface of the nozzle to obtain the upper surface shape of the drainage sand;

[0012] Step S5, shape finishing: Fit the scanned shape to obtain a fitted shape with an upward convex arc in the cross-sectional view, compare the scanned shape with the fitted shape, determine the defect location, use the catheter to accurately add sand to the defect location, and continue scanning until the upper surface shape of the drainage sand cross-sectional view is an upward convex arc, and the overall shape is mushroom-shaped.

[0013] In the above solution, chromium drainage sand is used when roughly adding sand in step S1.

[0014] In the above scheme, when the surface of the drainage sand is vibrated in step S2, three mechanical vibration rods are inserted into the drainage sand in the form of an equilateral triangle.

[0015] In the above solution, zirconium drainage sand is used when spirally adding sand in step S3.

[0016] In the above solution, the average particle size of the drainage sand during the spiral sand addition in step S3 is smaller than the average particle size of the drainage sand during the rough sand addition in step S1.

[0017] In the above scheme, when spirally adding sand in step S3, the funnel guide tube moves in a circular motion around the nozzle axis with a fixed angular velocity and a uniformly decreasing circumferential diameter.

[0018] In the above scheme, when the scanned shape is compared with the fitted shape, the height of the corresponding point of the fitted shape is subtracted from the scanned shape point to obtain the maximum height difference. The fitted shape is translated upward by the maximum height difference to obtain the target shape. The place where the target shape does not match the scanned shape is the defect location.

[0019] Furthermore, when the target shape is higher than the scan shape by 1 mm, it is considered that the target shape does not match the scan shape.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] According to one embodiment of the present invention, the shape of the drainage sand can be scanned during the sand adding process, and the shape can be fitted to obtain the defect position and accurately add sand, and finally the upper surface shape of the drainage sand cross-sectional view is a mushroom-shaped filling state with an upward convex arc, thereby improving the automatic pouring rate of the ladle.

[0022] According to one embodiment of the present invention, two layers of drainage sand are used for sand addition, wherein the lower layer uses chromium drainage sand and the upper layer uses zirconium drainage sand, which can reduce the use of zirconium drainage sand and save costs.

[0023] According to one embodiment of the present invention, the particle size of the lower layer of chromium drainage sand is larger than the particle size of the upper layer of zirconium drainage sand, and after the lower layer of chromium drainage sand is oscillated, the particle size of the upper surface of the chromium drainage sand will be significantly larger than the particle size of the bottom surface of the zirconium drainage sand. The fine particle size of the drainage sand leads to a larger contact interface, which is conducive to the development of the sintering behavior of the drainage sand, thereby ensuring that the sintered layer is concentrated on the zirconium drainage sand and controlling the thickness of the sintered layer to a certain extent.

[0024] Note that the description of these effects does not preclude the existence of other effects. One embodiment of the present invention does not necessarily have all of the above effects. Effects other than the above can be clearly seen and extracted from the description of the specification, drawings, claims, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a flow chart of an embodiment of the present invention.

[0026] Figure 2 Schematic diagram of spiral sand adding according to one embodiment of the present invention.

[0027] Figure 3 Schematic diagram of adding sand according to one embodiment of the present invention.

[0028] In the figure, 1. sprue; 2. chromium drainage sand; 3. zirconium drainage sand; 4. sintering layer. DETAILED DESCRIPTION

[0029] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "front", "back", "left", "right", "up", "down", "axial", "radial", "vertical", "horizontal", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0031] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0032] Figure 1 and Figure 3 As shown, a preferred embodiment of the ladle drainage sand adding method is shown, which includes the following steps:

[0033] Step S1, roughly adding sand: closing the bottom of the ladle nozzle, using a funnel guide to add drainage sand into the ladle nozzle until the height of the drainage sand is higher than the upper surface of the nozzle;

[0034] Step S2, surface leveling: oscillating the drainage sand to make it evenly distributed, using a scraper to scrape off excess drainage sand from the upper surface of the nozzle so that the upper surface of the drainage sand coincides with the upper surface of the nozzle, and using a vacuum cleaner to suck away the scraped drainage sand;

[0035] Step S3, spiral sand adding: spirally moving the funnel guide tube to add drainage sand to the upper surface of the water inlet, and making the center of the upper surface of the drainage sand convex;

[0036] Step S4, model scanning: using a 3D scanner and model scanning software to scan the drainage sand on the upper surface of the nozzle to obtain the upper surface shape of the drainage sand;

[0037] Step S5, shape finishing: Fit the scanned shape to obtain a fitted shape with an upward convex arc in the cross-sectional view, compare the scanned shape with the fitted shape, determine the defect location, use the catheter to accurately add sand to the defect location, and continue scanning until the upper surface shape of the drainage sand cross-sectional view is an upward convex arc, and the overall shape is mushroom-shaped.

[0038] According to this embodiment, preferably, chromium drainage sand 2 is used in the rough sand addition in step S1. The main raw materials of chromium drainage sand 2 are chromite and quartz sand, which have high density, high melting point, good fluidity, high refractoriness, strong resistance to molten steel penetration, and can maintain a high automatic pouring rate even after long-term contact with molten steel.

[0039] According to this embodiment, preferably, when the surface of the drainage sand is oscillated in step S2, three mechanical vibrating rods are inserted into the drainage sand in the shape of an equilateral triangle. This can prevent the drainage sand from being concentrated on one side of the sprue and causing overflow when the sprue is not fully filled.

[0040] According to this embodiment, preferably, zirconium drainage sand 3 is used during the spiral sand addition in step S3. Zirconium drainage sand 3 is primarily made of zircon, has round particles, and offers advantages such as low thermal expansion, good thermal conductivity, high density, strong resistance to molten steel penetration, and excellent stability. It has long been considered an ideal ladle drainage sand material. Due to its high price, zirconium drainage sand 3 is rarely used on-site. Therefore, using chromium drainage sand 2 in the lower layer and zirconium drainage sand 3 in the upper layer can reduce the amount of zirconium drainage sand 3 used and save costs.

[0041] When the sand is spirally added in step S3, the average particle size of the zirconium drainage sand 3 is smaller than the average particle size of the chromium drainage sand 2 when the sand is roughly added in step S1. The particle size of the drainage sand mainly affects the reaction interface, fluidity and thermal conductivity of the drainage sand. The fine particle size of the drainage sand leads to a larger contact interface, which is conducive to the development of the sintering behavior of the drainage sand. After the surface of the drainage sand is leveled and oscillated in step S2, the chromium drainage sand 2 with larger particle size is distributed in the upper layer, and the chromium drainage sand 2 with smaller particle size is distributed in the lower layer. At this time, zirconium drainage sand 3 with smaller average particle size is added to the upper surface of the chromium drainage sand 2, which will cause the contact surface of the zirconium drainage sand 3 and the chromium drainage sand 2 to form an obvious particle size differentiation layer. Since the drainage sand with smaller particle size sinters better, in the actual sintering process, the sintered layer 4 will be mainly reflected in the zirconium drainage sand 3 with smaller average particle size, which controls the thickness of the sintered layer 4 to a certain extent and improves the automatic pouring rate.

[0042] like Figure 2As shown, during the spiral sand addition in step S3, the funnel tube performs a circular motion around the nozzle axis at a constant angular velocity, uniformly reducing the circumferential diameter. Since the angular velocity remains constant while the diameter is reduced, the tube stays longer in areas with smaller diameters. As a result, the center height of the drainage sand upper surface becomes greater than the circumferential height, initially forming a central raised upper surface.

[0043] According to this embodiment, preferably, Geomagic for SolidWorks is used to scan the drainage sand on the upper surface of the nozzle during the model scanning.

[0044] When the scanned shape is compared with the fitted shape, the height of the corresponding point of the fitted shape is subtracted from the scanned shape point to obtain the maximum height difference. The fitted shape is translated upward by the maximum height difference to obtain the target shape. At this time, the height of the target shape will be greater than or equal to the height of the original scanned shape. Therefore, the place where the target shape does not match the scanned shape is the place that needs to be filled with drainage sand, that is, the defect position.

[0045] Furthermore, when the target shape is higher than the scan shape by 1 mm, it is considered that the target shape does not match the scan shape.

[0046] The present invention employs two layers of drainage sand for sand addition. The particle size of the lower layer, chromium drainage sand 2, is larger than that of the upper layer, zirconium drainage sand 3. This ensures that the sintered layer 4 is concentrated on the zirconium drainage sand 3, and to a certain extent controls the thickness of the sintered layer 4. Furthermore, the drainage sand shape can be scanned during the addition process, and fitting is performed to identify defect locations for precise sand addition. Ultimately, the drainage sand is filled in a mushroom-shaped state with an upwardly convex arc on the upper surface in a cross-sectional view, thereby improving the automatic pouring rate of the ladle.

[0047] It should be understood that although this specification is described according to various embodiments, not every embodiment contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0048] The series of detailed descriptions listed above are only specific descriptions of feasible embodiments of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent embodiments or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A ladle drainage sand adding method, characterized in that: The following steps are involved: Step S1, roughly adding sand: closing the bottom of the ladle nozzle, using a funnel guide to add drainage sand into the ladle nozzle until the height of the drainage sand is higher than the upper surface of the nozzle; Step S2, surface leveling: oscillating the drainage sand to make it evenly distributed, using a scraper to scrape off excess drainage sand from the upper surface of the nozzle so that the upper surface of the drainage sand coincides with the upper surface of the nozzle, and using a vacuum cleaner to suck away the scraped drainage sand; Step S3, spiral sand adding: spirally moving the funnel guide tube to add drainage sand to the upper surface of the water inlet, and making the center of the upper surface of the drainage sand convex; Step S4, model scanning: using a 3D scanner and model scanning software to scan the drainage sand on the upper surface of the nozzle to obtain the upper surface shape of the drainage sand; Step S5, shape finishing: Fit the scanned shape to obtain a fitted shape with an upward convex arc in the cross-sectional view, compare the scanned shape with the fitted shape, determine the defect location, use the catheter to accurately add sand to the defect location, and continue scanning until the upper surface shape of the drainage sand cross-sectional view is an upward convex arc, and the overall shape is mushroom-shaped.

2. The ladle drainage sand adding method according to claim 1, characterized in that: In the step S1, chromium drainage sand is used for rough sand addition.

3. The ladle drainage sand adding method according to claim 1, characterized in that: When the surface of the drainage sand is vibrated in step S2, three mechanical vibration rods are inserted into the drainage sand in the form of an equilateral triangle.

4. The ladle drainage sand adding method according to claim 1, characterized in that: When the spiral sand is added in step S3, zirconium drainage sand is used.

5. The ladle drainage sand adding method according to claim 1, characterized in that: The average particle size of the drainage sand during the spiral sand addition in step S3 is smaller than the average particle size of the drainage sand during the rough sand addition in step S1.

6. The ladle drainage sand adding method according to claim 1, characterized in that: During the spiral sand adding in step S3, the funnel guide tube performs a circular motion around the nozzle axis with a constant angular velocity and a uniformly decreasing circumferential diameter.

7. The ladle drainage sand adding method according to claim 1, characterized in that: When the scanned shape is compared with the fitted shape, the height of the corresponding point of the fitted shape is subtracted from the scanned shape point to obtain the maximum height difference. The fitted shape is translated upward by the maximum height difference to obtain the target shape. The place where the target shape does not match the scanned shape is the defect location.

8. The ladle drainage sand adding method according to claim 7, characterized in that: If the target shape is 1 mm higher than the scan shape, it is considered that the target shape does not match the scan shape.

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