A method for calculating the temperature drop of steel tapping in converter based on reference furnace

Abstract

The present invention discloses a method for calculating the temperature drop of steel tapping in a converter based on a reference furnace. The reference furnace mode is adopted to calculate the temperature drop of the furnace seat. The temperature drop of the furnace seat is mainly considered from six aspects: the temperature drop of steel tapping in the reference furnace, the alloy temperature drop in the reference furnace, the ladle temperature drop in the reference furnace, the temperature drop of the steel tapping process in the reference furnace, the temperature drop of the furnace seat state in the reference furnace, and the correction of the stop-blowing temperature in the reference furnace. The nearest multi-furnace reference furnace is selected to calculate the temperature drop of the furnace seat of the reference furnace. Finally, the temperature drop of steel tapping is equal to the sum of the temperature drop of the furnace seat of the reference furnace and the temperature drop of the alloy, the temperature drop of the ladle, the temperature drop of the steel tapping process, and the temperature drop of the furnace seat state. The method for calculating the temperature drop of steel tapping in the converter by the reference furnace solves the problem that the existing operator calculates the temperature drop of steel tapping based on his own experience, and the accuracy of calculating the temperature drop of steel tapping in the converter is improved by 10%. In addition, by applying this method to the model, the converter can automatically calculate the temperature drop of steel tapping, improve the calculation efficiency, and reduce the labor intensity of the operator.

Description

Technical Field

[0001] The invention belongs to the technical field of steelmaking production, and relates to a method for calculating the temperature drop of steel tapping from a converter based on a reference furnace. Background Art

[0002] The refining process will require a suitable ladle temperature from the converter according to the type of steel being smelted and the production rhythm. The task of the converter is to hit this ladle temperature so that the ladle temperature is within the range required by refining. The ladle temperature is equal to the converter stop blowing temperature minus the converter tapping temperature drop. The converter stop blowing temperature can be measured by a thermocouple probe. Therefore, in order to hit the ladle temperature, the converter tapping temperature drop must be accurately calculated. The tapping temperature drop is related to many factors, such as the furnace seat (different furnace seats have different tapping temperature drops), ladle status, tapping time, tapping alloy amount, alloy calorific value and heat absorption, auxiliary material heat absorption, converter shutdown time, etc. Since there are many factors affecting the tapping temperature drop and the calculation is complicated, the current operators calculate the converter tapping temperature drop based on their own experience. The calculation results depend largely on the operator's experience, and the calculation results have large fluctuations and the calculation accuracy is not high. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art, provide a method for calculating the temperature drop of steel out of a converter based on a reference furnace, improve a scientific calculation method, improve the accuracy of the calculation of the temperature drop of steel out, and solve the problem of large fluctuations in the temperature drop of steel out calculated by existing operators based on their own experience.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: a method for calculating the temperature drop of steel tapping from a converter based on a reference furnace, which specifically includes the following calculation steps:

[0005] Step 1: Calculate the temperature drop of the reference furnace base, specifically:

[0006] Reference furnace seat temperature drop = reference furnace tapping temperature drop - (reference furnace alloy temperature drop + reference furnace ladle temperature drop + reference furnace tapping process temperature drop + reference furnace seat state temperature drop correction + reference furnace stop blowing temperature correction); where,

[0007] Alloy temperature drop = alloy dosage * temperature drop coefficient. When calculating, lime (CaO) is included in the alloy temperature drop.

[0008] Ladle temperature drop = ladle state temperature drop, the ladle temperature drop is related to the time interval from the end of the previous ladle pouring to the start of the current ladle blowing, and the time interval is less than 3 hours;

[0009] Temperature drop during steel tapping = steel tapping time * temperature drop coefficient during steel tapping;

[0010] The temperature drop compensation of furnace seat status is to read the furnace age and shutdown time, and select the corresponding furnace status temperature drop compensation according to the static table;

[0011] Stop blowing temperature correction, specifically 1660℃, the correction amount is 0, for every 10℃ higher, the stop blowing temperature correction is 4℃, for every 10℃ lower, the stop blowing temperature correction is -4℃;

[0012] Step 2: Calculate the temperature drop of the converter steel tapping according to the reference furnace seat temperature drop calculated in step 1, specifically:

[0013] The temperature drop of steel tapping from converter = temperature drop of reference furnace base + temperature drop of alloy + temperature drop of ladle + temperature drop of steel tapping process + temperature drop of base state.

[0014] Furthermore, in step 1, a multi-furnace reference furnace is selected, and the temperature drop of the furnace seat of the reference furnace is obtained by weight calculation according to the temperature drop of the furnace seat of the multi-furnace reference furnace; wherein, the furnaces that meet the reference furnace must simultaneously meet the following conditions: furnaces without adding carbon powder, manganese carbon balls or carbon alloys; furnaces without re-blowing; having a stop-blowing temperature and a ladle temperature, and the stop-blowing temperature is between 1600-1690°C; the ladle temperature is between 1560-1660°C, and the stop-blowing temperature is greater than the ladle temperature; and the total oxygen blowing amount is greater than 14000Nm 3 ; If there is a dynamic temperature and a stop-blowing temperature, the stop-blowing temperature must be greater than the dynamic temperature.

[0015] Furthermore, the method for selecting a multi-furnace reference furnace is: take the most recent 25 heats, select 10 heats that meet the requirements, if less than 10 heats meet the requirements, at least 5 heats must be met; if none of the 25 heats meet the requirements, then push forward 25 heats until 5 heats that meet the requirements are obtained; the calculation weight of the temperature drop of the furnace seat of the multi-furnace reference furnace is specifically: when the number of heats of the same type of steel as the current steelmaking is ≥4, the weight of the temperature drop of the furnace seat accounts for 80%; when it is ≤3, the weight of the temperature drop of the furnace seat accounts for 61.8%.

[0016] The beneficial effects of the present invention are as follows: the method for calculating the temperature drop of steel tapping from the converter by the reference furnace solves the problem of large fluctuation of the temperature drop of steel tapping calculated by the existing operators based on their own experience, and the accuracy of calculating the temperature drop of steel tapping from the converter is improved by 10%. In addition, by applying this method to the model, the converter can automatically calculate the temperature drop of steel tapping, improve the calculation efficiency, and reduce the labor intensity of the operators. The method for calculating the temperature drop of steel tapping from the converter based on the reference furnace used in the present invention is mature and applied to the converter of Baosteel Zhanjiang Iron and Steel Plant. In addition, the present invention is also applicable to converters of other nominal capacities. DETAILED DESCRIPTION

[0017] The present invention is further described in detail below in conjunction with an embodiment, which is a method for calculating the temperature drop of steel tapping from a converter based on a reference furnace.

[0018] Example 1.

[0019] On the converter with a nominal capacity of 350 tons, converter No. 1, plan number 139897, tapping mark DT0144D1, molten iron 341.2 tons, scrap steel 31.9 tons, ladle state 21A, ladle weight 131.0 tons, refining process requires ladle temperature of 1625℃, ladle temperature range of 1615~1635℃, the reference furnace information of this furnace selection is shown in the table below, according to this method, the tapping temperature drop of this furnace is calculated to be 36℃, the actual tapping temperature drop is 39℃, the temperature drop calculated by this method is 3℃ lower than the actual tapping temperature, the calculation result is within the target range (±10℃), hitting the target.

[0020] Table 1 Reference furnace information for plan number 139897

[0021]

[0022] Example 2.

[0023] On the converter with a nominal capacity of 350 tons, converter No. 1, planning number 139900, tapping mark DT0144D1, molten iron 347.4 tons, scrap steel 36.1 tons, ladle state 21A, ladle weight 137.0 tons, the refining process requires the ladle temperature to be 1627℃, the ladle temperature range is 1617~1637℃, the reference furnace information of this furnace selection is shown in the table below, according to this method, the tapping temperature drop of this furnace is calculated to be 31℃, the actual tapping temperature drop is 30℃, the temperature drop calculated by this method is 1℃ higher than the actual tapping temperature drop, the calculation result is within the target range (±10℃), hitting the target.

[0024] Table 2 Reference furnace information for plan number 139900

[0025]

[0026] Example 3

[0027] On the converter with a nominal capacity of 350 tons, converter 2, plan number 139902, tapping mark DT0142D1, molten iron 339.0 tons, scrap steel 34.3 tons, ladle state 21A, ladle weight 131.0 tons, refining process requires ladle temperature of 1625℃, ladle temperature range is 1615~1625℃, the reference furnace information of this furnace selection is shown in the table below, according to this method, the tapping temperature drop of this furnace is calculated to be 40℃, the actual tapping temperature drop is 40℃, the temperature drop calculated by this method is 0℃ higher than the actual tapping temperature drop, the calculation result is within the target range (±10℃), hitting the target.

[0028] Table 3 Reference furnace information for plan number 139902

[0029]

[0030] The above contents are only used to illustrate the technical solution of the present invention. Simple modifications or equivalent substitutions of the technical solution of the present invention made by ordinary technicians in this field do not deviate from the essence and scope of the technical solution of the present invention.

Claims

1. A method for calculating the temperature drop of steel tapping in a converter based on a reference furnace, characterized in that: The specific calculation steps include the following: Step 1: Calculate the temperature drop of the reference furnace base, specifically: Reference furnace seat temperature drop = reference furnace tapping temperature drop - (reference furnace alloy temperature drop + reference furnace ladle temperature drop + reference furnace tapping process temperature drop + reference furnace seat state temperature drop correction + reference furnace stop blowing temperature correction); where, Alloy temperature drop = alloy dosage * temperature drop coefficient. When calculating, lime (CaO) is included in the alloy temperature drop. Ladle temperature drop = ladle state temperature drop, the ladle temperature drop is related to the time interval from the end of the previous ladle pouring to the start of the current ladle blowing, and the time interval is less than 3 hours; Temperature drop during steel tapping = steel tapping time * temperature drop coefficient during steel tapping; The temperature drop compensation of furnace seat status is to read the furnace age and shutdown time, and select the corresponding furnace status temperature drop compensation according to the static table; Stop blowing temperature correction, specifically 1660℃, the correction amount is 0, for every 10℃ higher, the stop blowing temperature correction is 4℃, for every 10℃ lower, the stop blowing temperature correction is -4℃; Step 2: Calculate the temperature drop of the converter steel tapping according to the reference furnace seat temperature drop calculated in step 1, specifically: The temperature drop of steel tapping from converter = temperature drop of reference furnace base + temperature drop of alloy + temperature drop of ladle + temperature drop of steel tapping process + temperature drop of base state.

2. The method for calculating the temperature drop of steel tapping in a converter based on a reference furnace according to claim 1, characterized in that: In the step 1, a multi-furnace reference furnace is selected, and the temperature drop of the furnace seat of the reference furnace is obtained by weight calculation according to the temperature drop of the furnace seat of the multi-furnace reference furnace; wherein, the furnaces meeting the requirements of the reference furnace must simultaneously meet the following requirements: furnaces without adding carbon powder, manganese carbon balls or carbon alloys; furnaces without re-blowing; furnaces with stop blowing temperature and ladle temperature, and the stop blowing temperature is between 1600-1690°C; ladle temperature is between 1560-1660°C, and the stop blowing temperature is greater than the ladle temperature; and the total oxygen blowing amount is greater than 14000Nm 3 ; If there is a dynamic temperature and a stop-blowing temperature, the stop-blowing temperature must be greater than the dynamic temperature.

3. The method for calculating the temperature drop of steel tapping in a converter based on a reference furnace according to claim 2, characterized in that: The method for selecting a multi-furnace reference furnace is: take the most recent 25 furnaces, select 10 furnaces that meet the requirements, if less than 10 furnaces meet the requirements, at least 5 furnaces must be met; if none of the 25 furnaces meet the requirements, then push forward 25 furnaces until 5 furnaces that meet the requirements are obtained; the calculation weight of the furnace seat temperature drop of the multi-furnace reference furnace is specifically: when the furnace seat temperature drop weight accounts for 80% of the weight of the furnace seat temperature drop when the furnace seat temperature drop weight accounts for 80% when the furnace seat temperature drop weight accounts for 61.8% when the furnace seat temperature drop weight accounts for 4 or more of the same type of steel as the current steelmaking; and when the furnace seat temperature drop weight accounts for 61.8% ...

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