Treatment method for increasing boiling speed after self-opening failure of molten metal pouring nozzle

Abstract

The invention discloses a treatment method for increasing the boiling speed after self-opening failure of a molten metal pouring nozzle, and belongs to the technical field of metal pouring. The treatment method comprises the steps that S1, after pouring residues are discharged, the inner surface of a container is cleaned; s2, when the risk that melt residues fall into an inner cavity of the seating brick exists in the hoisting process of the container, a protective cover is additionally arranged on the seating brick, and then the seating brick is fully covered; otherwise, directly executing S4; s3, when the container is transferred to the stuffing sand adding position, a water opening protection cover is removed through a sand adding funnel pipe part; s4, a metal wire is put into an inner cavity of the brick cup, and when casting is started through follow-up oxygen burning, the metal wire is burnt in oxygen to enable blockages to be rapidly melted; and S5, stuffing sand is added into the inner cavity of the seating brick through a sand adding funnel, the inner cavity of the seating brick is completely filled with the stuffing sand, the opening of the seating brick and the metal wire are completely covered, and the container is put into use after being treated. According to the invention, the boiling speed after the self-opening failure of the nozzle can be obviously improved, so that the harm of the self-opening failure of the nozzle to the production rhythm and the product quality is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of metal pouring, and in particular relates to a processing method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure. Background Art

[0002] The principle of automatic opening of the nozzle is that before the molten metal is injected into the container, the nozzle and the inner cavity of the base brick are filled with drainage sand of amorphous refractory material of a specific particle size. After the molten metal is injected, the surface of the drainage sand is rapidly sintered to form a shell to prevent the molten metal from penetrating into the drainage sand layer, thereby constructing a structure with a sintered layer on the upper part and a granular layer on the lower part. At the beginning of the pouring operation, by opening the nozzle slide, the granular drainage sand at the lower part flows out, and the sintered layer shell at the upper part cannot withstand the static pressure of the molten metal and breaks, allowing the molten metal to flow out of the nozzle, realizing automatic pouring.

[0003] As we all know, thanks to the long-term and unremitting efforts of metallurgical workers at home and abroad, the quality of drainage sand has been continuously improved, and the self-opening rate of the nozzle has been quite high. However, in the actual production process, due to operational errors, the injection of low-temperature molten metal or slag flows into the nozzle and the inner cavity of the seat brick before and after the filling of the drainage sand; some batches of drainage sand are of poor quality, and excessive sintering causes the shell to be too thick to be destroyed by the molten metal, or it cannot be sintered and washed away by the molten metal, causing the molten metal to flow into the particle layer mentioned above and solidify, and the particle layer cannot flow out by itself due to agglomeration; and the molten metal stays in the container for too long, causing the drainage sand to be over-sintered. These problems cannot be completely avoided, so there is still a certain probability that the nozzle will fail to open automatically. Once the nozzle fails to open automatically, it is necessary to use oxygen to boil the nozzle manually for pouring. In actual operation, since the blockage is non-flammable, it is often difficult to boil, which leads to serious interference with the production process. The molten metal is oxidized by a large amount of oxygen in the process, the quality decreases, and even forced to stop production due to the inability to boil in the end. Manual boiling of water nozzles requires workers to operate on pouring equipment, close contact with high-temperature molten metal, harsh working environment, high labor intensity and high risk factor. Therefore, reducing the difficulty of boiling after the failure of the molten metal pouring nozzle to open automatically, especially taking corresponding measures when it is known that there is a risk of self-opening failure that cannot be eliminated in a short time, so as to increase the boiling speed and final boiling rate, has a significant improvement effect. Summary of the invention

[0004] In order to solve the technical problems existing in the known technology, the present invention provides a processing method for improving the boiling speed of the molten metal pouring nozzle after the failure of self-opening. The method can significantly improve the boiling speed after the failure of self-opening of the nozzle, thereby reducing the negative impact of the failure of self-opening of the nozzle on the production rhythm and product quality.

[0005] The object of the present invention is to provide a method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure, comprising:

[0006] S1. After the residual discharge, clean the inner surface of the container;

[0007] S2. When there is a risk of melt residue falling into the inner cavity of the seat brick during the container lifting, a protective cover is added to the seat brick to cover the seat brick and leave a margin; otherwise, execute S4;

[0008] S3. When the container is transferred to the position for adding drainage sand, use the sand adding funnel to remove the water inlet protection cover;

[0009] S4. Put the metal wire pressed into a nearly spherical shape (sphere or ellipsoid) into the inner cavity of the seat brick; if oxygen is subsequently fired and poured, the metal wire will burn in the blown oxygen to release heat, thereby quickly melting the blockage;

[0010] S5. Use the sand adding funnel to add drainage sand into the inner cavity of the seat brick, so that the drainage sand completely fills the inner cavity of the seat brick and completely covers the seat brick opening and the metal wire. At this point, the container is processed and can be put into use.

[0011] Preferably, in S2, a plug hole cooperating with a metal guide rod is provided at the center of gravity of the nozzle protection cover; the nozzle protection cover is accurately added to the base brick by using the metal guide rod.

[0012] Preferably, the guide rod can be shaken back and forth and left and right during addition.

[0013] Preferably, the nozzle protection cover is made of a steel plate or a refractory inorganic non-metallic material plate.

[0014] Preferably, in S4, if the metal wire cannot be accurately put into the inner cavity of the seat brick, the sand-added funnel tube is used to push the metal wire into the inner cavity of the seat brick.

[0015] Preferably, the metal wire is made of a metal that is the same as or similar to the molten metal contained in the container, or has a lower oxygen potential, but should not be made of a metal that contaminates the molten metal.

[0016] Preferably, the diameter of the metal wire is 4 mm to 10 mm.

[0017] Preferably, the porosity is controlled by the ratio of the bulk density of the metal wire pressed into a sphere or ellipsoid to the true density of the material used, so that the base porosity of the metal wire pressed into a nearly spherical shape is 50% to 70%.

[0018] The advantages and positive effects of the present invention are:

[0019] The present invention utilizes a nozzle protection cover and a metal wire, which can significantly increase the boiling speed after the nozzle fails to open automatically, thereby reducing the negative impact of the nozzle failure on the production rhythm and product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the structure of the nozzle protection cover in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned purpose, control system and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] The technical solution of the present invention is:

[0023] A method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure, which is applicable to the pouring process after metal smelting, and the method comprises:

[0024] 1. After the residual discharge is completed, the inner surface of the container should be cleaned routinely.

[0025] 2. If there is a large amount of residual melt in the container, there is a risk of it falling into the inner cavity of the base brick during lifting. The metal guide rod should be used to place the nozzle protection cover on the nozzle. During the addition process, the guide rod can be shaken to make the nozzle protection cover slide down smoothly and cover the base brick. If the residual melt is completely discharged, this step can be omitted. The design of the nozzle protection cover is as follows: Figure 1 As shown, a circular hole is provided at the center of gravity (in this embodiment, it is circular, so the center of gravity is located at the center of the circle) so that it can slide to the specified position along the metal guide rod. The thickness and shape of the nozzle protection cover do not need to be strictly limited, but only need to ensure that it can cover the mouth of the seat brick and leave an appropriate margin to avoid excessive weight and facilitate removal before adding drainage sand. In actual production, the nozzle protection cover can be made of steel plate or refractory inorganic non-metallic material plate. In order to reduce costs, it is recommended to use waste materials.

[0026] 3. After the container is transferred to the position for adding drainage sand, the sand-adding funnel tube should be used to remove the nozzle protection cover, and the metal wire pressed into a nearly spherical shape should be put into the inner cavity of the base brick. If the metal wire is not accurately put in, the sand-adding funnel tube can be used to push it into the inner cavity of the base brick. The function of the metal wire is that when the subsequent pouring fails and oxygen is burned, the metal wire can burn in the blown oxygen, release heat, and quickly melt the blockage. Metal wires of the same or similar metal material as the container can be used, or other more active metal wires that do not pollute the metal contained can be used. For example, steel wire or iron wire can be used for steel ladle containing molten steel. The diameter of the metal wire should be 4mm to 10mm, and the cross-sectional shape is not strictly required, and a round shape is preferred. It is pressed into a nearly spherical shape through a scrap steel baling device to ensure uniform pores and not affect the inflow and outflow of drainage sand. The reference porosity is 50%-70%, which can be appropriately adjusted according to the fluidity of the drainage sand; the porosity is controlled by the ratio of the volume density of the metal wire to the true density of the material used.

[0027] 4. Use the sand adding funnel to add drainage sand into the inner cavity of the seat brick, making sure that the drainage sand completely fills the inner cavity of the seat brick and covers the seat brick opening and metal wire. At this point, the container is processed and can be put into use.

[0028] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are within the scope of the technical solution of the present invention.

Claims

1. A method for improving the boiling speed of a molten metal pouring nozzle after the molten metal pouring nozzle fails to open automatically, characterized in that: include: S1. After the residual discharge, clean the inner surface of the container; S2. When there is a risk of melt residue falling into the inner cavity of the seat brick during the container lifting, a protective cover is added to the seat brick to cover the seat brick and leave a margin; otherwise, execute S4; S3. When the container is transferred to the position for adding drainage sand, use the sand adding funnel to remove the water inlet protection cover; S4, putting a metal wire pressed into a sphere or ellipsoid into the inner cavity of the seat brick; when the subsequent oxygen is burned and poured, the metal wire will burn in the blown oxygen, releasing heat, so that the blockage will melt quickly; S5. Use the sand adding funnel to add drainage sand into the inner cavity of the seat brick, so that the drainage sand completely fills the inner cavity of the seat brick and completely covers the seat brick opening and the metal wire. At this point, the container is processed and can be put into use.

2. The method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure according to claim 1 is characterized in that: In S2, a plug hole cooperating with the metal guide rod is opened at the center of gravity of the nozzle protection cover; the nozzle protection cover is added to the nozzle by using the metal guide rod.

3. The method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure according to claim 2 is characterized in that: When joining, you can shake the guide rod forward, backward, left and right.

4. The method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure according to claim 1 is characterized in that: The nozzle protection cover is made of a steel plate or a refractory inorganic non-metallic material plate.

5. The method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure according to claim 1 is characterized in that: In S4, if the metal wire cannot be accurately inserted into the inner cavity of the seat brick, the sand-adding funnel tube is used to push the metal wire into the inner cavity of the seat brick.

6. The method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure according to claim 1 is characterized in that: The metal wire is made of the same material as the molten metal contained in the container, or a metal with a lower oxygen potential.

7. The method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure according to claim 1 is characterized in that: The diameter of the metal wire is 4 mm to 10 mm.

8. The method for improving the boiling speed of a molten metal pouring nozzle after self-opening failure according to claim 1 is characterized in that: The porosity is controlled by utilizing the ratio of the volume density of the metal wire pressed into a sphere or ellipsoid to the true density of the material used, so that the base porosity of the metal wire of the sphere or ellipsoid is 50% to 70%.

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