Method for intelligent steel burning of wide and heavy plate heating furnace

Abstract

The application discloses a kind of wide and thick plate heating furnace intelligent steel burning method, belong to thick plate rolling production field.The method includes thick plate heating furnace slab target temperature determination, slab each section end temperature determination, determine the minimum in-furnace time of slab, remaining in-furnace time calculation model, slab in-furnace, in section time calculation, heating furnace set temperature optimization calculation, optimization heating furnace pause processing strategy, air excess coefficient setting model.The method disclosed in the application can effectively improve the heating furnace steel burning automation rate by about 20%, which has a positive significance for reducing the workload of operators and improving the efficiency of field operation.Meanwhile, by accurately controlling the slab heating temperature, the slab discharge temperature hit rate can be effectively improved, which has a certain effect on improving the slab heating quality.And by slab heating temperature control, heating furnace fuel consumption can be appropriately reduced, and slab heating cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to thick plate rolling production, in particular to a method for intelligent steel heating of a wide and thick plate heating furnace. BACKGROUND

[0002] In the thick plate rolling production process, the heating of the raw material slab is mainly completed by a continuous step-by-step or push-type heating furnace. The slab heating target is generally the minimum in-furnace time of the slab and the average temperature of the slab at the out-furnace point, so as to ensure the uniformity of the slab heating and the complete austenitization and solid solution of the alloy elements. For each steel plant, the fuel consumption of slab heating is an important cost indicator. For a rolling plant with an annual output of 1 million tons, the annual fuel consumption cost can reach more than 80 million yuan. Therefore, the energy saving and consumption reduction of the slab heating process has been a continuous improvement work for steel enterprises.

[0003] Due to the diversity of slab materials and rolling specifications, as well as the difference in the in-furnace temperature of the hot-charged slab, the in-furnace time and the heating temperature (heating curve) of the slab are also different. When different slabs with different heating requirements are continuously charged into the furnace, the temperature control of each section of the heating furnace is increased in difficulty. The slab heating temperature is positively correlated with the fuel consumption. Under the condition of meeting the stable out-furnace rhythm, it is very critical to complete the heating of the slab at each position in the furnace with the minimum heating temperature setting. In addition, in the actual production process, the slab out-furnace rhythm is always dynamically changing, and the furnace temperature setting also needs to be adjusted in time.

[0004] The slab heating temperature target and setting requirement is dynamically related to the position in the furnace and the moving speed. Dynamic adjustment and correction of the temperature setting are needed to reduce the fuel consumption. In domestic thick plate plants, the furnace temperature setting of each section is mainly controlled by the staff according to the out-furnace time requirement, and the dynamic adjustment is tracked regularly for a long time. The dependence on the energy and experience of the operating personnel is relatively high. There are many factors to be considered in temperature setting, including variety, specification, rhythm prediction, and different heating requirements of the same section in the furnace, etc. It is relatively difficult to achieve unified operation requirements, and it also poses a great challenge to the realization of automatic steel heating of the heating furnace.

[0005] At present, due to the influence of factors such as slab specification, process and slab charging temperature, the in-furnace time and the heating temperature (heating curve) of the slab are also different. When different slabs with different heating requirements are continuously charged into the furnace, the temperature control of each section of the heating furnace is increased in difficulty. Influenced by the change of rolling rhythm, the operating personnel need to adjust the temperature in the furnace to ensure that the temperature of each section of the slab and the out-furnace temperature meet the production requirements. Due to the different rolling rhythms of different steel slabs, the temperature in the furnace needs to be adjusted many times. Due to the quality requirements of the steel plate rolling, the slab heating temperature needs to be adjusted in combination with the rolling state of the rolling mill, so as to ensure the normal rolling of the rolling mill and meet the rolling quality of the steel plate. SUMMARY

[0006] The application aims to provide a method for intelligent steel heating of a wide and thick plate heating furnace.

[0007] Technical scheme: A method for intelligent steel heating of a wide and thick plate heating furnace, comprising:

[0008] ① Determination of slab discharge target temperature

[0009] According to the discharge target temperature requirement of the rolling plan issued by L3, the slab of special steel is adjusted according to the requirements of the rolling line, and the priority is determined according to different requirement levels; according to the rolling experience summary of the rolling line, the target discharge temperature of the non-special steel slab is reduced, and the discharge target temperature of the rolling plan issued by L3 is adjusted downward under the condition of meeting the rolling requirements; according to the determined slab discharge temperature in the system, the difference between the slab width and the finished product thickness is fully considered, and the target discharge temperature is corrected;

[0010] ② Determination of slab segment end temperature

[0011] The target temperature of each segment of the slab is determined by using big data method, and the expert rule library is established;

[0012] ③ Determination of minimum slab in-furnace time

[0013] The minimum in-furnace time of the slab is determined according to the process requirements, and the minimum in-furnace time of the slab is optimized and adjusted according to the slab charging temperature;

[0014] ④ Residual in-furnace time calculation model

[0015] Through the historical slab heating performance, combined with the slab specification and heating process parameters, the direct rolling interval of each steel plate is obtained, so as to obtain the residual in-furnace time and the residual in-segment time of all the existing slabs in the furnace;

[0016] ⑤ Slab in-furnace and in-segment time calculation

[0017] According to the minimum in-furnace time, the step beam moving cycle, the rolling rhythm and the timing of the steel drawing rhythm time, the in-furnace time of the slab is calculated; according to the in-furnace time of the slab and the position of the slab, the in-segment time of the slab is calculated;

[0018] ⑥ Optimization calculation of heating furnace setting temperature

[0019] According to the necessary furnace temperature calculated by each segment of the heating furnace, the setting temperature of each segment of the heating furnace is calculated by weighted average according to the weight, and the final setting temperature of each segment is obtained after limiting the amplitude;

[0020] ⑦ Optimization of heating furnace rest strategy

[0021] According to actual production experience, the heating furnace rest time is used to determine the furnace temperature set value of each section of the heating furnace by using a big data method, and an expert rule base is researched and established for furnace temperature setting in actual production, so that the rest strategy is adjusted according to different rest.

[0022] 7. Air excess coefficient setting model

[0023] According to the air flow, the gas flow, the heat value and the oxygen content information, the optimal excess air coefficient of each heating furnace section is determined.

[0024] Preferably, the determined slab target discharge temperature of the system is corrected, and the upper and lower limits are not exceeded.

[0025] Preferably, in the determination of the slab section end temperature, historical heating data is used to build a table from the dimensions of the furnace time, the charging temperature and the discharge temperature, and the slab section end target temperature is set, and the slab section end target temperature is adjusted reasonably after considering the factors of steel grade, width and finished product thickness.

[0026] Preferably, in the heating furnace set temperature optimization calculation, the newly added expert rules meet the special heating requirements of the slab temperature rise requirements; the temperature rise and temperature drop setting correction is carried out in advance according to the actual working condition and process requirement of the production line; and the heating target is determined according to the comprehensive different requirements under the working condition of the same furnace and the same process section of the slab with different heating requirements, so as to meet the automatic furnace burning requirement.

[0027] Beneficial effects: the method disclosed by the application can effectively improve the automatic rate of the heating furnace by about 20%, which has a positive significance for reducing the work load of the operator and improving the on-site operation efficiency. At the same time, through accurate control of the slab heating temperature, the slab discharge temperature hit rate can be effectively improved, which has a certain effect on improving the slab heating quality. And through the control of the slab heating temperature, the heating furnace fuel consumption can be appropriately reduced, and the slab heating cost can be reduced. DETAILED DESCRIPTION

[0028] In order to make the technical scheme of the application clearer, the application will be further described in detail below in combination with specific embodiments.

[0029] EMBODIMENT

[0030] A method for intelligent steel burning of a wide and thick plate heating furnace, comprising:

[0031] Slab discharge target temperature determination

[0032] According to the target temperature requirement of the rolling plan issued by L3, the target temperature of the special steel slab is adjusted according to the requirements of the rolling line, and the priority is determined according to different requirements; the target temperature of the non-special steel slab is reduced according to the rolling experience of the rolling line, and the target temperature of the rolling plan issued by L3 is adjusted downward under the condition of meeting the rolling requirements; the target temperature is corrected according to the slab width and the thickness difference of the finished product (not more than the upper and lower limit requirements).

[0033] Determination of slab segment end temperature

[0034] The target temperature of each segment of the slab is determined by using big data method, and the expert rule library is established. Mainly use historical heating data to build table from furnace time, charging temperature, discharge temperature and other dimensions, set the target temperature of slab segment end, if necessary, reasonably adjust the target temperature of slab segment end after considering the factors of steel grade, width, finished product thickness, etc.

[0035] Determination of minimum slab furnace time

[0036] The minimum slab furnace time is determined according to the process requirements, and the minimum slab furnace time is optimized and adjusted according to the slab charging temperature.

[0037] Residual furnace time calculation model

[0038] The residual furnace time calculation model is relatively mature, which can be used to calculate the residual furnace time of the subsequent slab according to the current steelmaking rhythm, but the prerequisite is to establish automatic steelmaking rhythm in the heating furnace. The heating furnace of thick plate is affected by factors such as variety specification, different team human difference, etc. There is great uncertainty in predicting the residual furnace time of the subsequent slab by using the current rhythm. Through the historical slab heating performance, combined with slab specification, heating process and other parameters, the direct rolling interval of each steel plate is obtained, so as to obtain the residual furnace time and residual segment time of all the existing slabs in the furnace.

[0039] Calculation of slab furnace and segment time

[0040] According to the minimum furnace time, step beam moving cycle, rolling rhythm and timing of steel drawing rhythm time, the slab furnace time is calculated; according to the slab furnace time and slab position, the slab segment time is calculated;

[0041] Optimization calculation of heating furnace setting temperature

[0042] According to the necessary furnace temperature calculated by the steel plate in each section of the heating furnace, the set temperature of each section of the heating furnace is calculated by weighted average according to the weight, and the final set temperature of each section is obtained after limiting the amplitude. Mainly including the newly added expert rule to meet the special heating requirements of the slab heating requirements; according to the actual working condition and process requirement of the production line, the heating and cooling setting correction is carried out in advance; ensure that the slabs with different heating requirements are in the same furnace and the same process section, and the heating target is clear according to the different requirements, and the automatic furnace burning requirement is met.

[0043] Optimization of heating furnace rest strategy

[0044] According to the actual production experience, the heating furnace rest time is determined by the big data method, and the furnace temperature setting value of each section of the heating furnace is determined. The expert rule base is established for the furnace temperature setting in actual production. Therefore, according to the different rest time, the rest strategy is adjusted, so as to realize the goal of saving fuel and ensuring normal production at the end of the furnace shutdown.

[0045] Air excess coefficient setting model

[0046] The furnace atmosphere of the heating furnace directly affects the oxidation loss and energy consumption of the billet, but due to the frequent fluctuation of the calorific value of the gas in the production process, the combustion of the heating furnace changes constantly, and the model needs to determine the best excess air coefficient of each heating furnace section according to the air flow, gas flow, calorific value, oxygen content and other information.

[0047] According to the production slab specification and process, the expert library procedure table of the slab heating temperature in the heating furnace of different process slabs is established, the upper and lower limits of the temperature control in the heating furnace of different process slabs are set according to the actual control requirements on site, and the slab discharge temperature is ensured to meet the production requirements.

[0048]

[0049] Note: Heating codes "1, 4, 5, 9" represent different process requirements of slabs, "1" represents ordinary structural steel, which has a loose requirement on heating temperature, and the upper and lower limits of the discharge temperature can be controlled within ± 50℃, "4" and "9" represent special steel, which has strict requirements on the heating temperature of the slab, and the upper and lower limits of the discharge temperature can be controlled within (-20, +30)℃, and "5" represents die steel, which has a loose requirement on the heating temperature, and the upper and lower limits of the discharge temperature can be controlled within ± 50℃.

[0050] And add the heating furnace burning model procedure table writing / reading function module. Add the model rule table data structure in the heating model system, develop the procedure table writing / reading function interface, and read and write the data in the expert library in real time during model calculation. Add the data reading interface of the heating furnace burning model procedure table, add the burning model calculation completion event definition, and the event publishing logic.

[0051] Through the above technology, the automation rate of the heating furnace is effectively improved, the intelligent upgrading of the thick plate heating furnace is promoted, the working strength of personnel is reduced, the slab heating quality is improved, and the slab heating fuel consumption is reduced, which has significance and value for popularization and use.

[0052] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method for intelligent steelmaking of a wide and thick plate heating furnace, characterized by, Comprise: ① Slab target temperature determination According to the target temperature requirement of the rolling plan issued by L3, adjust the slab of special steel according to the requirements of the rolling line, and determine the priority according to different requirements; According to the rolling experience of the rolling line, reduce the target temperature, and adjust the target temperature downward under the condition of meeting the rolling requirements; According to the determined slab target temperature in the system, fully consider the width difference of the slab and the thickness difference of the finished product, and correct the target temperature; ② Slab end temperature determination Determine the target temperature of each section of the slab by big data method, and establish expert rule library; ③ Determine the minimum slab time in the furnace Determine the minimum slab time in the furnace according to the process requirements, and optimize and adjust the minimum slab time in the furnace according to the slab charging temperature; ④ Residual time calculation model Through the historical slab heating performance, combined with the slab specification and heating process parameters, the direct rolling interval of each steel plate is obtained, so as to obtain the residual time in the furnace and the residual time in the section of all the existing slabs in the furnace; ⑤ Slab time in the furnace and in the section calculation According to the minimum time in the furnace, the moving cycle of the walking beam, the rolling rhythm and the timing of the steel drawing rhythm time, the slab time in the furnace is calculated; According to the slab time in the furnace and the slab position, the slab time in the section is calculated; ⑥ Heating furnace set temperature optimization calculation According to the necessary furnace temperature calculated by each section of the heating furnace, the set temperature of each section of the heating furnace is calculated by weighted average according to the weight, and the final set temperature of each section is obtained after limiting the amplitude; ⑦ Optimization of heating furnace rest strategy According to the actual production experience of heating furnace rest time, the furnace temperature setting value of each section of the heating furnace is determined by big data method, the expert rule library is established, which is used for the furnace temperature setting in actual production; According to the different rest, the rest strategy is adjusted; ⑧ Air excess coefficient setting model According to the air flow, gas flow, calorific value and oxygen content information, the best excess air coefficient of each heating furnace section is determined.

2. The method of intelligent steelmaking for a wide and heavy plate heating furnace according to claim 1, characterized by, The slab target temperature determined in the system is corrected, which does not exceed the upper and lower limit requirements.

3. The method of intelligent steelmaking for a wide and heavy plate heating furnace according to claim 1, characterized by, In the determination of the slab end temperature of each section, the historical heating data is used to build a table from the dimensions of the time in the furnace, the charging temperature and the discharge temperature, and the slab end target temperature is set, while considering the factors of steel grade, width and finished product thickness to adjust the slab end target temperature reasonably.

4. The method of intelligent steelmaking for a wide and heavy plate heating furnace according to claim 1, characterized by, In the heating furnace set temperature optimization calculation, it includes the new expert rule to meet the special heating requirements of the slab; According to the actual working condition and process requirement of the production line, the temperature rising and falling is set and corrected in advance; Ensure that the slabs with different heating requirements are in the same furnace and the same process section, and the heating target is clear under the condition of comprehensive demand, which meets the automatic furnace burning requirement.

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