Operation method for protective pouring of slab continuous casting machine

Abstract

The invention relates to an operation method for protective pouring of a slab continuous casting machine. The operation method comprises the following steps that S1, sealant is prepared; s2, upper nozzle sealant is smeared; s3, smearing of a submersed nozzle sealant; s4, mounting the submersed nozzle; s5, checking after the submersed nozzle is installed; s6, smearing the outer side of the end face of the submersed nozzle; and S7, mounting the blind plate. After the specific operation method of the protective pouring mode of adding the sealant to the upper nozzle is innovated and optimized, the situation that protective pouring fails in the casting process of the continuous casting machine can be stably achieved, quality guarantee can be achieved for high-quality steel, the ordered production rhythm of a steel mill can be stabilized, and the production efficiency is improved. And the production cost of a steel mill is further reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of continuous casting machines, and in particular relates to an operating method for protective casting of a slab continuous casting machine. Background Art

[0002] Continuous casting machine protection pouring refers to an important technical means to prevent the molten steel from being secondary oxidized during the pouring of molten steel by the continuous casting machine. The emergence of effective and stable protection pouring technology is one of the signs of the increasingly perfect development of continuous casting technology. The use of full-process protection pouring technology is an important measure to improve the quality of the ingot. In the actual molten steel pouring process, it is generally divided into two protective pourings, one is the protective pouring in the tundish area, and the other is the protective pouring in the crystallizer area. At present, the protective pouring form of the tundish area is relatively simple and stable, and the protective pouring form of the crystallizer area is diverse, such as adding argon to the upper water inlet, the integral water inlet and the upper water inlet plus sealant. The above three protective pouring methods have their own advantages. Steel mills can choose different protective pouring methods according to their own varieties and costs. However, if the method of adding sealant to the upper water inlet is not operated properly, the protection pouring will fail, which needs to be solved. Summary of the invention

[0003] In view of this, the purpose of the present invention is to provide an operating method for protective pouring of a slab continuous casting machine. After innovative optimization of the specific operating method of the protective pouring method with sealant added to the water inlet, it can stably achieve the situation where the protective pouring does not fail during the casting process of the continuous casting machine. It can not only achieve quality assurance for high-quality steel, but also stabilize the orderly production rhythm of the steel plant, further reduce the production cost of the steel plant, so as to solve the above-mentioned problem.

[0004] To achieve the above object, the technical solution adopted by the present invention is: an operating method for protective pouring of a slab continuous casting machine, the operating method comprising the following steps: S1. Preparation of sealant; S2. Apply sealant to the water inlet; S3. Applying sealant to the immersed nozzle; S4. Installation of immersion nozzle; S5. Inspection of immersion nozzle after installation; S6, coating on the outer side of the submerged nozzle end face; S7. Blind plate installation.

[0005] Preferably, in S1, the sealant is a high-temperature sealant material specially used in the metallurgical industry, with a viscosity of 2-10 Pa•s, and is controlled on site according to the viscosity standard of honey, requiring the temperature to be controlled at 25-35°C before application.

[0006] Preferably, in S2, the prepared sealant is applied to the argon gas channel and the gas sealing ring to block the gas channel.

[0007] Preferably, in S3, the coating is applied to the end face of the immersion nozzle in parallel to the direction of the side hole of the immersion nozzle, and the coating is required to be uniform and free of pores, with a coating thickness of 2-4mm, and the coating is applied to form a slope at the entrance end of the immersion nozzle.

[0008] Preferably, in S4, the coated immersion nozzle is installed on the immersion nozzle device along the entrance end, and the immersion nozzle is pushed to the bottom of the upper nozzle by a hydraulic cylinder.

[0009] Preferably, in S5, after pushing the hydraulic cylinder to one side and staying for 5-10 minutes, use a strong flashlight to illuminate the joint gap between the upper water inlet and the immersion water inlet and both sides of the slideway of the immersion water inlet device along the water inlet installation direction to check whether there is a gap. If there is a gap, apply sealant again.

[0010] Preferably, in S6, the coating is applied again at the gap where the upper water inlet and the immersion water inlet meet to ensure that there is no gap or omission on the outer side of the contact surface between the upper water inlet and the immersion water inlet.

[0011] Preferably, in S7, after the operations of S1-S6 are completed, after staying for 5-8 minutes, check whether there are cracks in the sealant at the gap where the upper water inlet and the immersion water inlet are connected. If there are cracks, a blind plate needs to be installed after applying the sealant. If there are no cracks, the blind plate can be installed.

[0012] The beneficial effects of the present invention are as follows: 1. Through the implementation of the present invention, a method is provided for protecting the pouring of a continuous casting machine, which can effectively achieve the protection of pouring without failure; 2. Through the implementation of the invention, after using this protective pouring method, this method can change the molten steel flow field in the crystallizer and provide options for specific steel grade requirements; 3. Through the implementation of the invention, not only the surface quality of the ingot can be improved, but also the number of continuous pulling furnaces can be increased, thereby further reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the main structure of the water inlet of the present invention; Figure 2 It is a schematic diagram of the top view of the water inlet of the present invention; Figure 3 It is a structural schematic diagram of the submerged nozzle of the present invention.

[0014] The numbers in the figure are: 1 is the upper water inlet, 2 is the argon gas channel, 3 is the upper water inlet end face, 4 is the inclined surface, 5 is the gas sealing ring, 6 is the submerged water inlet, 7 is the submerged water inlet end face, and 8 is the entry end. DETAILED DESCRIPTION

[0015] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments: like Figures 1 to 3 As shown, in a certain type of steel, the water nozzle is protected by adding sealant. The following operations are performed about 80 minutes before the continuous casting machine starts pouring: 1. Stir the sealant with a stirrer and control the viscosity to be similar to honey. The temperature should be controlled at 25-35℃ before applying. 2. Apply the prepared sealant to the argon gas channel and the gas sealing ring to block the gas channel; 3. Parallel to the side hole direction of the immersion nozzle, apply the coating on the end face of the immersion nozzle. The coating should be even and free of pores. The coating thickness should be 2-4mm. Apply the coating into a slope at the entrance end of the immersion nozzle. 4. Install the coated immersion nozzle on the immersion nozzle device along the inlet end, and use the hydraulic cylinder to push the immersion nozzle to the bottom of the upper nozzle; 5. After pushing the hydraulic cylinder to one side and staying there for 5-10 minutes, use a strong flashlight to illuminate the joint gap between the upper nozzle and the immersion nozzle and both sides of the immersion nozzle device slideway along the nozzle installation direction to check whether there is a gap between the two contact surfaces and whether the immersion nozzle device slideway is full. If there is a gap or it is not full, apply sealant again; 6. Apply the coating again at the gap between the upper nozzle and the immersed nozzle to ensure that there is no gap or omission on the outer side of the contact surface between the upper nozzle and the immersed nozzle; 7. After completing the above operations, wait for 6 minutes, check that there are no cracks in the sealant at the gap between the upper water inlet and the immersed water inlet, and install the blind plate.

[0016] Working principle of the present invention: 1. Through the implementation of the present invention, a method is provided for protecting the pouring of the continuous casting machine, which can effectively achieve the protection of the pouring from failure; 2. Through the implementation of the invention, after using this protective pouring method, this method can change the molten steel flow field in the crystallizer and provide options for specific steel grade requirements; 3. Through the implementation of the invention, not only the surface quality of the ingot can be improved, but also the number of continuous pulling furnaces can be increased, thereby further reducing production costs.

[0017] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for operating protective pouring of a slab continuous casting machine, characterized in that: The operation method comprises the following steps: S1. Preparation of sealant; S2. Apply sealant to the water inlet; S3. Applying sealant to the immersed nozzle; S4. Installation of submerged nozzle; S5. Inspection of immersion nozzle after installation; S6, coating on the outer side of the submerged nozzle end face; S7. Blind plate installation.

2. The operating method for protective pouring of a slab continuous casting machine according to claim 1, characterized in that: In S1, the sealant is a high-temperature sealant material specially used in the metallurgical industry, with a viscosity of 2-10 Pa •s. The viscosity is controlled on site according to the standard of honey viscosity, and the temperature is required to be controlled at 25-35° C. before application.

3. The operating method for protective pouring of a slab continuous casting machine according to claim 1, characterized in that: In S2, the prepared sealant is applied to the argon gas channel and the gas sealing ring to block the gas channel.

4. The operating method for protective pouring of a slab continuous casting machine according to claim 1, characterized in that: In S3, parallel to the direction of the side hole of the immersion nozzle, the end face of the immersion nozzle is fully coated. The coating is required to be uniform and free of pores. The coating thickness is 2-4mm, and it is coated into a slope at the entrance end of the immersion nozzle.

5. The operating method for protective pouring of a slab continuous casting machine according to claim 1, characterized in that: In S4, the coated immersion nozzle is installed on the immersion nozzle device along the inlet end, and the immersion nozzle is pushed to the right below the upper nozzle by a hydraulic cylinder.

6. The operating method for protective pouring of a slab continuous casting machine according to claim 1, characterized in that: In S5, after pushing the hydraulic cylinder to one side and staying for 5-10 minutes, use a strong flashlight to illuminate the joint gap between the upper nozzle and the immersion nozzle and both sides of the slideway of the immersion nozzle device along the nozzle installation direction to check whether there is a gap. If there is a gap, apply sealant again.

7. The operating method for protective pouring of a slab continuous casting machine according to claim 1, characterized in that: In S6, apply the coating once more at the gap where the upper water inlet and the immersed water inlet meet to ensure that there is no gap or omission on the outer side of the contact surface between the upper water inlet and the immersed water inlet.

8. The operating method for protective pouring of a slab continuous casting machine according to claim 1, characterized in that: In S7, after the operations of S1-S6 are completed, stay for 5-8 minutes and check whether there are cracks in the sealant at the gap between the upper water inlet and the immersed water inlet. If there are cracks, it is necessary to install a blind plate after applying the sealant. If there are no cracks, the blind plate can be installed.

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