Method for improving liquid level calculation accuracy of converter secondary model molten pool

Abstract

The invention relates to a method for improving the liquid level calculation accuracy of a converter secondary model molten pool, and belongs to the technical field of ferrous metallurgy control methods. According to the technical scheme, before blowing is started, the liquid level height of a converter molten pool is calculated; after blowing is finished, a sublance TSO probe is adopted for measuring the liquid level height, and after data are uploaded, the secondary model conducts terminal point molten pool liquid level height data correction; calculating a difference value between the molten steel liquid level height at the blowing end point and the molten steel liquid level height at the model calculation end point, and performing model calculation updating in a normal range; if a normal range is exceeded, considering an abnormal factor, and not carrying out model feedback updating. The method has the beneficial effects that automatic steelmaking control fluctuation caused by molten pool liquid level fluctuation can be reduced, the method can be applied to the steelmaking process on a large scale, operation is easy and convenient, and the effect is stable; the molten pool liquid level calculation accuracy of the converter secondary steelmaking model can be effectively improved, the automatic steelmaking rate is effectively improved, and the product quality and the social and economic benefits are improved.

Description

Technical Field

[0001] The invention relates to a method for improving the calculation accuracy of a molten pool liquid level of a secondary converter model, and belongs to the technical field of iron and steel metallurgy control methods. Background Art

[0002] As the most important link in a steelmaking plant, converter steelmaking has a direct impact on the quality of molten steel and its process control and endpoint indicators, which are also the main factors affecting cost control. In the actual production process of converter steelmaking, the converter endpoint molten steel level height varies greatly due to fluctuations in various factors such as charging volume and blowing loss, which seriously affects the control of the automated steelmaking process. Because the change in molten steel level directly affects the actual control range of the oxygen lance position, and the oxygen lance position is the main factor affecting slag removal, how to accurately grasp the change in converter molten steel level, achieve precise oxygen lance position control, and improve the hit rate of automated steelmaking endpoint is a technical problem in the steelmaking industry. Patent CN114913225B provides a real-time measurement method for converter liquid level based on monocular vision, which focuses on determining the change in molten steel level by adding a camera system when the converter is tapping steel; Patent CN117740103A provides a molten pool liquid level intelligent detection method and system, which focuses on determining the molten pool liquid level by combining different characteristics of slag analysis after using probe sampling. One of the above two patents uses the addition of equipment to improve the detection of the molten pool liquid level, and the other uses a probe for measurement, but neither involves the improvement of the prediction accuracy of the secondary model; on the other hand, the innovation of equipment has brought about an increase in steelmaking costs, affecting the overall efficiency of the steel plant. Overall, the above two methods are not the best choices. Summary of the invention

[0003] The purpose of the present invention is to provide a method for improving the calculation accuracy of the molten pool liquid level of a converter secondary model. The molten pool liquid level at the end point of blowing is calculated by using the molten steel weight and the molten pool height under standard conditions, and is calibrated with the help of actual auxiliary gun measurement deviation. A feedback correction parameter is formed in combination with a large number of test results, so that the molten pool liquid level result calculated by the model is closer to the actual one, and the fluctuation of automated steelmaking control caused by molten pool liquid level fluctuation can be reduced. The method can be applied to the steelmaking process on a large scale, with simple operation and stable effect. The calculation accuracy of the molten pool liquid level of the converter secondary steelmaking model can be effectively improved, the automated steelmaking rate can be effectively improved, the quality of the product and the social and economic benefits can be improved, and the above-mentioned problems existing in the background technology can be effectively solved.

[0004] The technical solution of the present invention is: a method for improving the calculation accuracy of the molten pool level of a converter secondary model, comprising the following steps:

[0005] S1. Before blowing begins, calculate the liquid level of the converter molten pool;

[0006] S2. After blowing, the liquid level is measured by the auxiliary gun TSO probe. After the data is uploaded, the secondary model corrects the terminal molten pool liquid level data.

[0007] S3. Calculate the difference between the molten steel level at the blowing end point and the molten steel level at the model calculation end point, and update the model calculation within the normal range; if it exceeds the normal range, it is considered to be an abnormal factor and no model feedback update is performed.

[0008] In step S1, the calculation formula for the converter molten pool liquid level is as follows:

[0009]

[0010] in, The height of the molten steel level at the end point of the model calculation, in cm;

[0011] is the height of the molten steel level under standard conditions, in cm;

[0012] The weight of molten steel under standard conditions, in ton;

[0013] Calculate the weight of molten steel for the model, in ton;

[0014] is the model prediction calibration parameter, in cm / ton.

[0015] In step S2, the formula is as follows:

[0016]

[0017] in, is the height of the molten steel level at the end of blowing, in cm;

[0018] It is used to measure the molten steel level height at the auxiliary gun at the end of blowing, in cm.

[0019] In step S3, the judgment standard of the difference between the molten steel level at the blowing end point and the molten steel level at the model calculated end point is as follows:

[0020] If the difference between the molten steel level at the blowing end point and the molten steel level at the model calculation end point is ≤ 20 cm, the model calculation is updated according to the following formula:

[0021]

[0022] Wherein, Fb is the correction value of the model feedback parameter, and Fb is selected to be greater than or equal to 0.1 and less than or equal to 0.3 according to the nominal capacity of the converter; B is the height of the molten steel level at the end of blowing, in cm; The height of the molten steel level measured by the auxiliary gun at the end of blowing, in cm;

[0023] If the difference between the molten steel level at the blowing end point and the molten steel level at the model calculation end point is greater than 20 cm and less than or equal to 50 cm, the model calculation is updated according to the following formula:

[0024]

[0025] Among them, Fb X is the model feedback parameter correction value, Fb X According to the nominal capacity of the converter, select a range greater than 0.3 and less than or equal to 1.2;

[0026] If the difference between the molten steel level at the end of blowing and the molten steel level at the end of model calculation is greater than 50cm, it is considered to be an abnormal factor and the model feedback update is not performed.

[0027] The beneficial effects of the present invention are as follows: the melt pool level at the end point of blowing is calculated by utilizing the weight of molten steel and the height of the melt pool under standard conditions, and is calibrated with the help of actual sub-gun measurement deviations, and feedback correction parameters are formed in combination with a large number of test results, so that the melt pool level result calculated by the model is closer to the actual one, and the fluctuation of automated steelmaking control caused by melt pool level fluctuations can be reduced. The present invention can be applied on a large scale in the steelmaking process, with simple operation and stable effect. The calculation accuracy of the melt pool level in the converter secondary steelmaking model can be effectively improved, the automated steelmaking rate can be effectively improved, and the quality of the product as well as the social and economic benefits can be improved. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the invention implementation cases clearer, a clear and complete description will be given below in combination with the technical solutions in the implementation cases. Obviously, the implementation cases described are only a small part of the implementation cases of the present invention, rather than all the implementation cases. Based on the implementation cases in the present invention, all other implementation cases obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] A method for improving the calculation accuracy of the molten pool level of a converter secondary model comprises the following steps:

[0030] S1. Before blowing begins, calculate the liquid level of the converter molten pool;

[0031] S2. After blowing, the liquid level is measured by the auxiliary gun TSO probe. After the data is uploaded, the secondary model corrects the terminal molten pool liquid level data.

[0032] S3. Calculate the difference between the molten steel level at the blowing end point and the molten steel level at the model calculation end point, and update the model calculation within the normal range; if it exceeds the normal range, it is considered to be an abnormal factor and no model feedback update is performed.

[0033] In step S1, the calculation formula for the converter molten pool liquid level is as follows:

[0034]

[0035] in, The height of the molten steel level at the end point of the model calculation, in cm;

[0036] is the height of the molten steel level under standard conditions, in cm;

[0037] The weight of molten steel under standard conditions, in ton;

[0038] Calculate the weight of molten steel for the model, in ton;

[0039] is the model prediction calibration parameter, in cm / ton.

[0040] In step S2, the formula is as follows:

[0041]

[0042] in, is the height of the molten steel level at the end of blowing, in cm;

[0043] It is used to measure the molten steel level height at the auxiliary gun at the end of blowing, in cm.

[0044] In step S3, the judgment standard of the difference between the molten steel level at the blowing end point and the molten steel level at the model calculated end point is as follows:

[0045] If the difference between the molten steel level at the blowing end point and the molten steel level at the model calculation end point is ≤ 20 cm, the model calculation is updated according to the following formula:

[0046]

[0047] Wherein, Fb is the correction value of the model feedback parameter, and Fb is selected to be greater than or equal to 0.1 and less than or equal to 0.3 according to the nominal capacity of the converter; B is the height of the molten steel level at the end of blowing, in cm; The height of the molten steel level measured by the auxiliary gun at the end of blowing, in cm;

[0048] If the difference between the molten steel level at the blowing end point and the molten steel level at the model calculation end point is greater than 20 cm and less than or equal to 50 cm, the model calculation is updated according to the following formula:

[0049]

[0050] Among them, Fb X is the model feedback parameter correction value, Fb X According to the nominal capacity of the converter, select a range greater than 0.3 and less than or equal to 1.2;

[0051] If the difference between the molten steel level at the end of blowing and the molten steel level at the end of model calculation is greater than 50cm, it is considered to be an abnormal factor and the model feedback update is not performed.

[0052] Example 1

[0053] In a top and bottom double-blown converter with a nominal capacity of 120 tons, low-carbon steel of Ml08Al is smelted. After the converter is loaded with molten iron and scrap steel, the molten pool level calculated by the converter secondary model is 897cm. After the actual blowing end, the molten pool level measured by the auxiliary gun is 895cm. The deviation between the two is 2cm. After calculation using the correction formula, the standard molten pool level is 900cm, and the model correction coefficient Fb is selected as 0.1. After correction, the standard molten pool level is corrected to 900.5cm.

[0054] Example 2

[0055] In a top and bottom double-blown converter with a nominal capacity of 120 tons, the smelting steel grade is SWRCH22A cold heading steel. After the converter is loaded with molten iron and scrap steel, the molten pool level calculated by the converter secondary model is 899cm. After the actual blowing end, the auxiliary gun measures the molten pool level to be 879cm. The deviation between the two is 20cm. After calculation using the correction formula, the standard molten pool level is 900cm, and the model correction coefficient Fb is selected as 0.3. After correction, the standard molten pool level is corrected to 903.3cm.

[0056] Example 3

[0057] In a top and bottom double-blown converter with a nominal capacity of 120 tons, 40Cr medium-carbon steel is smelted. After the converter is loaded with molten iron and scrap steel, the molten pool level calculated by the converter secondary model is 890cm. After the actual blowing end, the auxiliary gun measures the molten pool level to be 890cm. The deviation between the two is 10cm. After calculation using the correction formula, the standard molten pool level is 900cm, and the model correction coefficient Fb is selected as 0.2. After correction, the standard molten pool level is corrected to 902cm.

[0058] Example 4

[0059] In a top and bottom double-blown converter with a nominal capacity of 120 tons, high-carbon steel U71Mn is smelted. After the converter is loaded with molten iron and scrap steel, the molten pool level calculated by the converter secondary model is 890cm. After the actual blowing end, the auxiliary gun measures the molten pool level to be 865cm. The deviation between the two is 25cm. After calculation using the correction formula, the standard molten pool level is 900cm, and the model correction coefficient Fb is selected as 0.4. After correction, the standard molten pool level is corrected to 914cm.

[0060] Example 5

[0061] In a top and bottom double-blown converter with a nominal capacity of 120 tons, the smelting steel grade is U75V high-carbon steel. After the converter is loaded with molten iron and scrap steel, the molten pool level calculated by the converter secondary model is 880cm. After the actual blowing end, the auxiliary gun measures the molten pool level to be 910cm. The deviation between the two is 30cm. After calculation using the correction formula, the standard molten pool level is 900cm, and the model correction coefficient Fb is selected as 0.8. After correction, the standard molten pool level is corrected to 892cm.

[0062] Example 6

[0063] In a top and bottom double-blown converter with a nominal capacity of 120 tons, 37Mn5 medium-carbon steel is smelted. After the converter is loaded with molten iron and scrap steel, the molten pool level calculated by the converter secondary model is 900cm. After the actual blowing end, the auxiliary gun measures the molten pool level to be 850cm. The deviation between the two is 50cm. After calculation using the correction formula, the standard molten pool level is 900cm, and the model correction coefficient Fb is selected as 1.2. After correction, the standard molten pool level is corrected to 960cm.

[0064] Example 7

[0065] In a top and bottom double-blown converter with a nominal capacity of 100 tons, high-carbon steel of GCr15 is smelted. After the converter is loaded with molten iron and scrap steel, the molten pool level calculated by the converter secondary model is 797cm. After the actual blowing end, the auxiliary gun measures the molten pool level to be 795cm. The deviation between the two is 5cm. After calculation using the correction formula, the standard molten pool level is 800cm, and the model correction coefficient Fb is selected as 0.1. After correction, the standard molten pool level is corrected to 800.5cm.

[0066] Example 8

[0067] In a top and bottom blown converter with a nominal capacity of 260 tons, the smelting steel grade is SAE100 low carbon steel. After the converter is loaded with molten iron and scrap steel, the molten pool level calculated by the converter secondary model is 1000cm. After the actual blowing end, the auxiliary gun measures the molten pool level to be 960cm. The deviation between the two is 4cm. After calculation using the correction formula, the standard molten pool level is 1000cm, and the model correction coefficient Fb is selected as 1.0. After correction, the standard molten pool level is corrected to 1040cm.

[0068] The above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention is described in detail with reference to the above embodiments, those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. Any modification or partial replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for improving the calculation accuracy of the molten pool level of the converter secondary model, characterized in that The following steps are involved: S1. Before blowing begins, calculate the liquid level of the converter molten pool; S2. After blowing, the liquid level is measured by the auxiliary gun TSO probe. After the data is uploaded, the secondary model corrects the terminal molten pool liquid level data. S3. Calculate the difference between the molten steel level at the blowing end point and the molten steel level at the model calculation end point, and update the model calculation within the normal range; if it exceeds the normal range, it is considered to be an abnormal factor and no model feedback update is performed.

2. A method for improving the calculation accuracy of the molten pool level of a converter secondary model according to claim 1, characterized in that: In step S1, the calculation formula for the converter molten pool liquid level is as follows: in, The height of the molten steel level at the end point of the model calculation, in cm; is the height of the molten steel level under standard conditions, in cm; The weight of molten steel under standard conditions, in ton; Calculate the weight of molten steel for the model, in ton; is the model prediction calibration parameter, in cm / ton.

3. The method for improving the calculation accuracy of the molten pool level of the converter secondary model according to claim 1 is characterized in that: In step S2, the formula is as follows: in, is the height of the molten steel level at the end of blowing, in cm; It is used to measure the molten steel level height at the auxiliary gun at the end of blowing, in cm.

4. The method for improving the calculation accuracy of the molten pool level of the converter secondary model according to claim 1 is characterized in that: In step S3, the judgment standard of the difference between the molten steel level at the blowing end point and the molten steel level at the model calculated end point is as follows: If the difference between the molten steel level at the blowing end point and the molten steel level at the model calculation end point is ≤ 20 cm, the model calculation is updated according to the following formula: Wherein, Fb is the correction value of the model feedback parameter, and Fb is selected to be greater than or equal to 0.1 and less than or equal to 0.3 according to the nominal capacity of the converter; is the height of the molten steel level at the end of blowing, in cm; The height of the molten steel level measured by the auxiliary gun at the end of blowing, in cm; If the difference between the molten steel level at the blowing end point and the molten steel level at the model calculation end point is greater than 20 cm and less than or equal to 50 cm, the model calculation is updated according to the following formula: Among them, Fb X is the model feedback parameter correction value, Fb X According to the nominal capacity of the converter, select a range greater than 0.3 and less than or equal to 1.2; If the difference between the molten steel level at the end of blowing and the molten steel level at the end of model calculation is greater than 50cm, it is considered to be an abnormal factor and the model feedback update is not performed.

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