Fixed-width casting method of slab continuous casting machine

Abstract

The invention discloses a fixed-width casting method of a slab continuous casting machine. The fixed-width casting method comprises the following steps that S1, the middle position of the common width of a casting machine is adopted as the fixed casting width; s2, adjusting the width and the taper of the crystallizer; s3, whether dummy bar insertion is completed or not is checked, and automatic sealing is conducted; s4, casting is conducted according to a fixed mode; s5, the speed increasing rate of the steel grade is set; s6, checking whether the width and the taper of the crystallizer are adjusted or not; and S7, width correction management is conducted on the cast-on blank. According to the method, the production of the slab with the planned width is realized, the simplification of dummy bar head spare part management, the preparation of a standardized sealing material, the automatic standardized operation of crystallizer sealing and the standardized casting control flow are realized through the improvement of the method, and then the restrictive bottleneck links of continuous casting automation and less-manpower production are eliminated.

Description

Technical Field

[0001] The invention relates to a continuous casting process automation control technology, and more specifically to a fixed-width pouring method for a slab continuous casting machine. Background Art

[0002] At present, all domestic slab continuous casting needs to adjust the width of the ingot head according to the casting plan before pouring. That is, different width sections need to select and replace ingot heads of different sizes or adjust the width size through the adjustment block, and send the ingot rod into the casting machine for sealing and pouring. Replacing the ingot head is a labor-intensive task, and the sealing work after the ingot rod is inserted into place requires two people to do it at the same time for each flow. The operation is complicated and has high standardization requirements. Deviations in the sealing operation of the crystallizer are also prone to cause problems such as steel leakage during pouring, premature stripping or stripping failure during ingot stripping, which is a difficulty in the current promotion of continuous casting automation operation.

[0003] Generally, each stream of a continuous casting machine needs to be equipped with 3 ingot heads of different sizes, 6 ingot heads for 2 streams, and a set of 3 ingot heads of matching sizes as spares. A total of 9 ingot heads are required for a continuous casting machine. Due to the weight of the ingot heads, they cannot be replaced manually and need to be equipped with corresponding lifting devices to assist. Replacing the ingot heads is time-consuming and laborious. Summary of the invention

[0004] In view of the above-mentioned defects existing in the prior art, the purpose of the present invention is to provide a fixed-width pouring method for a slab continuous casting machine to realize the production of slabs of planned width, and through this method, improvements are made to simplify the management of ingot head spare parts, prepare standardized sealing materials, automate and standardize the crystallizer sealing operation, and standardize the pouring control process, thereby eliminating the restrictive bottleneck links of continuous casting automation and less-manned production.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] A method for casting with a fixed width for a slab continuous casting machine comprises the following steps:

[0007] S1. Use the middle position of the commonly used width of the casting machine as the fixed pouring width;

[0008] S2. Adjust the width and taper of the crystallizer;

[0009] S3, check whether the dummy rod insertion and automatic sealing are completed;

[0010] S4, pouring in a fixed mode;

[0011] S5. Set the rate of increase of steel grade;

[0012] S6. Check whether the width and taper of the crystallizer have been adjusted;

[0013] S7. Carry out width correction management on the open casting.

[0014] Preferably, in step S2, the width and taper of both sides of the crystallizer are set based on the center point of the crystallizer.

[0015] Preferably, in step S4, the fixed mode includes adjusting the argon flow rate, the initial opening of the stopper rod, the liquid level rising speed, the time point and amount of adding slag for pouring, the seedling maintenance time, and the starting speed.

[0016] Preferably, in step S5, when the casting speed rises to 0.8-1.0 m / min, the crystallizer is automatically width-adjusted according to the target production width.

[0017] Preferably, when the width adjustment amount of the crystallizer is greater than 200 mm, the width adjustment is performed in two steps.

[0018] The fixed width pouring method of the slab continuous casting machine provided by the present invention adopts a fixed ingot pouring method according to the current pouring requirements of the slab continuous casting machine, and can avoid the previous operation of replacing and changing the size of the ingot head according to different cross-section requirements through the adjustment of the automatic (manual) mode, thereby meeting the casting conditions of the slab continuous casting machine. There are major changes in the previous replacement method that required multiple ingot heads of different sizes as spare parts, and the use of winches and other high-intensity labor output in multi-person mode. In addition, the coordinated implementation of this method with the automatic sealing method will enable the pouring operation to be completed by only one person, greatly improving productivity and reducing the number of spare parts. Its more far-reaching significance is that it promotes the progress of continuous casting automation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the process of the fixed-width pouring method of the present invention. DETAILED DESCRIPTION

[0020] In order to better understand the above technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0021] Combination Figure 1 As shown, a fixed-width pouring method for a slab continuous casting machine provided by the present invention comprises the following steps:

[0022] S1. Use the middle position of the commonly used width of the casting machine as the fixed opening width. For example, the casting width of a casting machine is 1000-2000mm, and the middle value of the commonly used width is 1500mm, that is, the size of the dummy head on the dummy rod is fixed to 1500mm;

[0023] S2. When preparing the crystallizer, according to different steel grades, the width and taper on both sides are set based on the center point of the crystallizer (there will be slight adjustments for different steel grades);

[0024] S3. After the dummy rod is inserted into the casting machine, customized sealing materials and related sealing components of fixed size are automatically placed in a fixed pattern;

[0025] S4, pouring according to a fixed mode (adjusting argon gas flow, initial opening of the stopper rod, liquid level rising speed, time and amount of slag addition, seedling maintenance time, and starting speed);

[0026] S5. Set different speed-up slopes according to the steel type to perform speed-up operation;

[0027] S6. After the speed is raised to the desired level, the width is automatically adjusted according to the target production width. When the width adjustment is greater than 200 mm, the width is adjusted twice (fixed opening pouring mode ends);

[0028] S7. Perform width correction management on the open casting billet (B billet).

[0029] In the above step S5, when the casting speed rises to 0.8-1.0 m / min, the width of the crystallizer is automatically adjusted according to the target production width.

[0030] According to the different requirements of the slab continuous casting machine for the opening of the casting section, a unified ingot head is first used. The above discussion has put forward the relative benefits and the disadvantages of using different ingot heads for opening the casting in the past. Therefore, an implementation plan for opening the casting with a fixed ingot head size is proposed. According to multiple tests and verifications, the opening operation is carried out in the fixed ingot mode, and the control and adjustment of the corresponding nodes are carried out to gradually achieve the required width of the casting slab. This method is proposed mainly for the purpose of promoting the development of continuous casting automation, combined with the batch and automation of continuous casting automatic sealing. The principle is mainly to open the casting by fixing the ingot size, and gradually adjust it after entering the casting state. This involves the adjustment of the slab pulling speed, width adjustment rate, and taper speed after the continuous casting opening. This method will be the main part of this patent and will be highlighted in the claims. However, since the specific values ​​are the result of many years of operation and hard summary, a range of values ​​is adopted.

[0031] The invention is used to solve the problem of frequent and high-strength starter head replacement and installation according to different cross-section requirements during continuous casting. After implementation, the manual work load and the reserve of starter heads can be greatly reduced.

[0032] The fixed-size pouring mode means that no matter what the production plan width is, the same size is used for pouring when CAST is poured. After pouring, when the casting speed rises to 0.8-1.0 meters, the width adjustment operation is carried out, and the crystallizer is adjusted to the target production width within the length of B billet (the first slab). This mode has great advantages for CAST casting machines with a large number of continuous casting furnaces, fast width adjustment speed, and relatively stable width adjustment function. At the same time, this process method does not require the ingot head to be changed, which has great benefits for the design of the equipment for automatic sealing of the crystallizer and the unified regulation of sealing materials, but it requires strict requirements for the formulation of process specifications for width adjustment after pouring (mainly including speed increase slope, speed increase gradient, crystallizer liquid level stability control during pouring, single width adjustment amount control, etc.).

[0033] The present invention is based on the continuous casting machine avoiding the replacement link of the dummy rod, realizing unmanned and less-manpowered casting, and achieving the purpose of fast and convenient safe casting operations. It is suitable for greatly reducing the difficulty of operation in the automatic sealing state of the continuous casting machine crystallizer, and promoting the process of unmanned and less-manpowered. After unifying the size of the dummy head for the pouring mode, it will be convenient for the intelligent batch production of continuous casting in the future. By establishing a digital model, it will promote progress in automatic pouring, automatic sealing, automatic monitoring and control, etc. It is to reduce the intensity of manual work in the current intelligent advancement and complex operating environment, and can greatly reduce the risks brought to the safety of pouring due to the instability of manual work.

[0034] The present invention first redefined the concept of fixing the dummy ingot for casting of slab continuous casting machine in the industry, and the design theory is mature. It also provides a number of technical points, which are the first of its kind in China and abroad. It has a high application value for continuous casting operations in similar occasions. It can be promoted and used in major domestic steel enterprises and has a very broad application prospect.

[0035] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. As long as they are within the spirit of the present invention, any changes or modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. A method for constant width casting of a slab continuous casting machine, characterized in that: The following steps are involved: S1. Use the middle position of the commonly used width of the casting machine as the fixed pouring width; S2. Adjust the width and taper of the crystallizer; S3, check whether the dummy rod insertion and automatic sealing are completed; S4, pouring in a fixed mode; S5. Set the rate of increase of steel grade; S6. Check whether the width and taper of the crystallizer have been adjusted; S7. Carry out width correction management on the open casting.

2. The method for constant width casting of a slab continuous casting machine according to claim 1, characterized in that: In the step S2, the width and taper of both sides of the crystallizer are set based on the center point of the crystallizer.

3. The method for constant width casting of a slab continuous casting machine according to claim 1, characterized in that: In step S4, the fixed mode includes adjusting the argon flow rate, the initial opening of the stopper rod, the liquid level rising speed, the time point and amount of adding slag for pouring, the seedling maintenance time, and the starting speed.

4. The method for constant width casting of a slab continuous casting machine according to claim 1, characterized in that: In step S5, when the casting speed rises to 0.8-1.0 m / min, the crystallizer is automatically adjusted in width according to the target production width.

5. The method for constant width casting of a slab continuous casting machine according to claim 4, characterized in that: When the width adjustment amount of the crystallizer is greater than 200 mm, the width adjustment is performed in two steps.

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