Rhythm-adaptive refining time dynamic allocation method

Abstract

The invention provides a rhythm self-adaptive refining time dynamic allocation method, which relates to the technical field of steel smelting and comprises the following steps: step 1, constructing a continuous casting remaining time prediction model; 2, calling the continuous casting remaining time prediction model at a key time node of refining of the current batch of molten steel; 3, according to the continuous casting remaining time and the current batch of remaining refining related operation time, the refining heating remaining time is obtained; and 4, according to the current heating gear and the refining heating remaining time, the remaining refining operation time is adjusted. Through the continuous casting remaining time prediction model and the temperature prediction model, the refining outbound temperature and time are controlled to meet the requirements of the continuous casting machine, and the continuous casting rate of the continuous casting machine is improved, so that the operation rate and the production efficiency of the continuous casting machine are remarkably improved.

Description

Technical Field

[0001] The invention relates to the technical field of steel smelting, and in particular to a rhythm-adaptive refining time dynamic allocation method. Background Art

[0002] At present, most steel mills adopt the process flow of "primary refining furnace (converter or electric furnace) - refining furnace (LF furnace) - continuous casting machine". In the production process, due to the numerous process flows and complex refining process, it is easy to have the delay of tapping from the primary refining furnace, delay of molten steel logistics, abnormal final pouring of continuous casting, plan adjustment, equipment failure, etc., and according to different steel grades and process requirements, there are range requirements for continuous casting pouring temperature. As a result, if you want to achieve continuous casting of the continuous casting machine, thereby significantly improving the operation rate and production efficiency of the continuous casting machine, the molten steel not only needs to reach the continuous casting machine at the end of the previous round of molten steel continuous casting, but the temperature of the molten steel also needs to meet the exit requirements. Too high or too low temperature will have an adverse effect on the quality of the continuous casting billet. Too high temperature will lead to problems such as reduced viscosity of molten steel, floating of inclusions, and crusting on the surface of the crystallizer; while too low temperature may lead to poor fluidity of molten steel, interruption of pouring, and billet shell defects.

[0003] In the prior art, the time control of the refining process relies on manual experience, and the feeding time, desulfurization time, heating time, temperature measurement and sampling time, and soft blowing time in the process are adjusted to meet the time requirements of the continuous casting machine as much as possible. Without data guidance, the end time of the previous round of continuous casting cannot be accurately known. Manual control of the refining time is inaccurate, arbitrary, and non-standardized.

[0004] The refining temperature control is usually controlled by a static model, that is, a certain heating rate is set in the control system, and the required heating time is statically calculated according to the initial temperature and target temperature requirements, and then the temperature measurement correction is performed. If the measured temperature value is lower than the target value, the heating is performed again. If the measured temperature value is higher than the target value, the cooling material is used for forced cooling or natural cooling is used. This method usually requires secondary heating, resulting in low production efficiency. Summary of the invention

[0005] The present invention is made in view of the above-mentioned problems, and its purpose is to provide a rhythm-adaptive refining time dynamic allocation method, which controls the refining outlet time of molten steel through a continuous casting remaining time prediction model, and controls the refining outlet temperature through a temperature prediction model. It can automatically adjust the transformer gear, automatically reduce the refining time to compensate for the heating time, control the refining outlet temperature and time to meet the requirements of the continuous casting machine, improve the continuous casting rate of the continuous casting machine, and thus significantly improve the operating rate and production efficiency of the continuous casting machine.

[0006] Specifically, a first aspect of the present invention provides a rhythm adaptive refining time dynamic allocation method, comprising the following steps: Step 1: Based on the past continuous casting process data, construct a prediction model for the remaining continuous casting time, with the formula as follows: ; Where: is the remaining continuous casting time; is the current weight of the continuous casting arm; is the weighed weight of the continuous casting arm when preset to leave the station; is the width of the continuous casting section; is the thickness of the continuous casting section; is the real-time casting speed of the casting machine; is the density of molten steel; The difference between the current weight of the continuous casting arm and the weighed weight of the continuous casting arm when preset to leave the station is the remaining molten steel weight of the current continuous casting arm. The width of the continuous casting section determines the production capacity and equipment adaptability of the continuous casting machine, while the thickness affects the production efficiency and product quality. The real-time casting speed of the continuous casting machine has an important impact on both production efficiency and slab quality.

[0007] Step 2: At the critical time node of the current batch of molten steel refining, call the prediction model for the remaining continuous casting time to predict the remaining continuous casting time of the previous batch of molten steel; To achieve continuous casting of multiple furnaces of molten steel, reduce the ladle change time, and improve production efficiency, it is necessary to predict the end time of continuous casting of the previous batch of molten steel at the critical time point, so as to adjust the refining process time in real time and make the current batch of molten steel reach the continuous casting machine at the time when the continuous casting of the previous batch of molten steel ends for smooth continuous casting.

[0008] Step 3: Based on the remaining continuous casting time and the remaining refining-related operation time of the current batch, obtain the remaining refining heating time; Step 4: According to the current heating gear and the remaining refining heating time, adjust the remaining refining operation time to ensure sufficient heating time and reach the target temperature when leaving the refining station.

[0009] Furthermore, the current weight of the continuous casting arm is calculated based on the weighing data of the support arm of the continuous casting turntable, and the condition for judging no ladle is that the arm weight is less than 30 tons.

[0010] Furthermore, when the number of support arms of the continuous casting turntable is 2, the calculation method of the current weight of the continuous casting arm is as follows: Case 1: If the weight of the first support arm is less than 30 tons and the weight of the second support arm is greater than or equal to 30 tons, then the current weight of the continuous casting arm is equal to the weight of the second support arm; Case 2: If the weight of the second boom is less than 30 tons and the weight of the first boom is greater than or equal to 30 tons, then the current weight of the continuous casting boom is equal to the weight of the first boom; Case 3: If the weights of both the first boom and the second boom are greater than or equal to 30 tons, then the current weight of the continuous casting boom is equal to the sum of the two minus the weight of the empty ladle corresponding to the boom with the smaller weight.

[0011] Furthermore, the key time nodes of the molten steel refining specifically include: measuring the temperature when entering the refining station, measuring the temperature for the first time after heating, and measuring the temperature after desulfurization ends.

[0012] Measuring the temperature for the first time after heating is the moment when the molten steel is measured and sampled for the first time after the heating and temperature-rising stage ends.

[0013] Furthermore, the remaining refining-related operation time includes at least one of the charging time, wire feeding time, desulfurization time, soft blowing time, temperature measurement and sampling time, electrode lifting time, and reserved margin time.

[0014] Furthermore, Step 4 specifically includes: calling the temperature prediction model. If the predicted temperature obtained from the current heating gear and the remaining refining heating time does not meet the refining station-out requirement, then at least one of the methods of increasing the heating gear and increasing the heating time is adopted to increase the refining station-out temperature until the requirement is met.

[0015] Furthermore, the temperature prediction model is: ; Wherein: is the predicted temperature of the molten steel; is the measured temperature of the molten steel; is the temperature rising speed of the molten steel under different gears; is the temperature drop of the furnace lining; is the temperature drop of the furnace charge; is the temperature drop of argon blowing; is the temperature drop of the flue gas; is the time interval; Furthermore, the increasing of the heating time is specifically to increase the heating time by compressing the time of some operation processes.

[0016] The time of compressing some operation processes is usually to compress the soft blowing time, but the compression amplitude is limited by the molten steel composition, temperature and the requirement of inclusion floating up, and actual operation needs to be carried out according to the on-site process conditions.

[0017] Further, if the predicted temperature of the molten steel still cannot reach the outbound requirement even when the two methods of increasing the heating gear and increasing the heating time are used simultaneously, an automatic alarm will be issued.

[0018] In a second aspect, the present invention also provides a computing device that has the function of implementing the method described in the first aspect above. The beneficial effects can be referred to the description in the first aspect and will not be elaborated here. The function can be implemented by hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions. In a possible design, the structure of the device includes an acquisition module and a training module. Optionally, a construction module may also be included. These modules can implement the functions of the training nodes in the method example of the first aspect above. For specific details, refer to the detailed description in the method example and will not be elaborated here.

[0019] In a third aspect, the present invention also provides a computing device that is used to implement the function of the method described in the first aspect above. The beneficial effects can be referred to the description in the first aspect and will not be elaborated here. The structure of the computing device includes a processor and a memory. The memory is used to store instructions and / or data. The memory is coupled to the processor. When the processor executes the program instructions stored in the memory, it can implement the functions of the training nodes in the example of the first aspect above. The structure of the computing device also includes a communication interface for communicating with other devices.

[0020] In a fourth aspect, the present invention also provides a computer-readable storage medium. Instructions are stored in the computer-readable storage medium. When it runs on a computer, it causes the computer to execute the methods in the first aspect and all possible designs of the first aspect.

[0021] In a fifth aspect, the present invention also provides a computer program product containing instructions. When it runs on a computer, it causes the computer to execute the methods in the first aspect and all possible designs of the first aspect.

[0022] In a sixth aspect, the present invention also provides a computing chip. The chip is connected to the memory. The chip is used to read and execute the software program stored in the memory and execute the methods in the first aspect and all possible implementation manners of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present drawings or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present drawings. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0024] Figure 1 It is the flow chart of the steps of the present invention; Figure 2 It is the primary temperature control flow chart of the embodiment of the present invention; The realization of the purpose of this attached drawing, functional features and advantages will be further described in conjunction with the embodiments with reference to the attached drawing. Specific embodiments

[0025] In order to make the purpose, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be described and explained below in conjunction with the attached drawing and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments provided by the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

[0026] Obviously, the attached drawings in the following description are only some examples or embodiments of the present invention. For those of ordinary skill in the art, without making creative efforts, the present invention can also be applied to other similar scenarios based on these attached drawings. In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, for those of ordinary skill in the art related to the content disclosed by the present invention, some design, manufacturing or production changes based on the technical content disclosed by the present invention are only conventional technical means and should not be understood as the content disclosed by the present invention being insufficient.

[0027] If there is no special indication, all implementation manners and optional implementation manners of the present invention can be combined with each other to form a new technical solution.

[0028] If there is no special indication, all technical features and optional technical features of the present invention can be combined with each other to form a new technical solution.

[0029] If there is no special indication, all steps of the present invention can be carried out in sequence or randomly, and preferably in sequence. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) carried out in sequence, or may also include steps (b) and (a) carried out in sequence. For example, it is mentioned that the method may further include step (c), indicating that step (c) can be added to the method in any order. For example, the method may include steps (a), (b) and (c), or may also include steps (a), (c) and (b), or may also include steps (c), (a) and (b), etc.

[0030] Unless otherwise specified, the terms "comprising" and "including" mentioned in the present invention are open-ended and can also be closed-ended. For example, the terms "comprising" and "including" can mean that other components not listed can also be included or comprised, or it can only include or comprise the listed components.

[0031] Unless otherwise specified, in the present invention, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) while B is true (or exists); or both A and B are true (or exist).

[0032] To better understand the solutions of the embodiments of the present invention, some related terms and concepts that may be involved in the embodiments of the present invention will be introduced below.

[0033] (1) Refining. The refining of steel is a crucial step in the steel production process. Its purpose is to remove impurities in pig iron, such as sulfur, phosphorus, etc., and adjust the composition of the steel to meet the requirements of specific uses. The refining process usually includes two stages: primary refining and secondary refining. In the primary refining stage, pig iron is preliminarily processed through a converter or an electric arc furnace. The main task of this stage is to remove carbon and other impurities in pig iron, such as sulfur and phosphorus, and at the same time carry out alloying to obtain molten steel with basic properties. Secondary refining, also known as secondary refining outside the furnace, is carried out after primary refining. Secondary refining can be carried out under vacuum, inert gas or reducing atmosphere to further remove gases and harmful impurities.

[0034] (2) Continuous casting. The core of the continuous casting process is to continuously pour molten steel into solid steel billets. The main steps include: loading the refined molten steel into a ladle, rotating the ladle to above the tundish through a turntable to ensure the temperature and composition of the molten steel are uniform; the molten steel in the ladle flows into the tundish through a sliding gate. The tundish plays a role in storing and secondary refining, and at the same time prevents secondary oxidation through covering slag; the molten steel in the tundish is injected into the mold through an immersion nozzle. The mold is the core equipment of the continuous caster, which is used to quickly cool and solidify the molten steel into a solid shell; the solidified shell continues to cool in the mold, and the temperature of the shell is further reduced through a spray cooling system to make it reach sufficient strength to support subsequent operations; when the shell is completely solidified, it is pulled out of the mold by a straightening machine and straightened to ensure the dimensional accuracy of the billet; finally, the continuous casting billet is cut into steel billets of a certain length according to needs for subsequent rolling or heat treatment.

[0035] In this embodiment, as Figure 1 shown, a rhythm adaptive refining time dynamic allocation method includes the following steps: Step 1: Based on the past continuous casting process data, construct a prediction model for the remaining continuous casting time, with the formula as follows: ; In this embodiment: = 140.8t; = 100t; = 1.38m; = 0.207m; = 1.40m / min; = 7.42 ; = 40.8 / 2.97 = 13.73min; The difference between the current weight of the continuous casting arm and the preset weighing weight of the continuous casting arm at the time of casting out is the remaining molten steel weight of the current continuous casting arm. The continuous casting section width determines the production capacity and equipment adaptability of the continuous casting machine, while the thickness affects the production efficiency and product quality. The real-time casting speed of the continuous casting machine has an important impact on both the production efficiency and the quality of the cast slab.

[0036] Step 2: At the key time node of the current batch of molten steel refining, call the prediction model for the remaining continuous casting time to predict the remaining continuous casting time of the previous batch of molten steel; In order to achieve continuous casting of multiple furnaces of molten steel, reduce the ladle change time, and improve the production efficiency, it is necessary to predict the end time of continuous casting of the previous batch of molten steel at the key time point, so as to adjust the refining process time in real time, so that the current batch of molten steel reaches the continuous casting machine at the time when the continuous casting of the previous batch of molten steel ends, and continuous casting is carried out smoothly.

[0037] Step 3: Obtain the remaining refining heating time based on the remaining continuous casting time and the remaining refining related operation time of the current batch; Step 4: Adjust the remaining refining operation time according to the current heating gear and the remaining refining heating time to ensure sufficient heating time and reach the target temperature when refining out of the station.

[0038] Furthermore, the current weight of the continuous casting arm is calculated based on the weighing data of the support arm of the continuous casting turntable, and the condition for judging no ladle is that the arm weight is less than 30 tons.

[0039] Furthermore, when the number of support arms of the continuous casting turntable is 2, the calculation method of the current weight of the continuous casting arm is as follows: Case 1: If the weight of the first support arm is less than 30 tons and the weight of the second support arm is greater than or equal to 30 tons, then the current weight of the continuous casting arm is equal to the weight of the second support arm; Case 2: If the weight of the second boom is less than 30 tons and the weight of the first boom is greater than or equal to 30 tons, then the current weight of the continuous casting boom is equal to the weight of the first boom; Case 3: If the weights of both the first boom and the second boom are greater than or equal to 30 tons, then the current weight of the continuous casting boom is equal to the sum of the two minus the weight of the empty ladle corresponding to the boom with the smaller weight.

[0040] Furthermore, the key time nodes for molten steel refining specifically include: measuring the temperature when entering the refining station, the first temperature measurement after heating, and the temperature measurement after desulfurization is completed.

[0041] The first temperature measurement after heating is the moment when the molten steel is measured and sampled for the first time after the heating and temperature-rising stage ends.

[0042] Furthermore, the remaining refining-related operation time includes at least one of the charging time, wire feeding time, desulfurization time, soft blowing time, temperature measurement and sampling time, electrode lifting time, and reserved margin time.

[0043] Furthermore, Step 4 specifically includes: calling the temperature prediction model. If the predicted temperature obtained from the current heating gear and the remaining refining heating time does not meet the refining-out station requirements, then at least one of the methods of increasing the heating gear and increasing the heating time is adopted to increase the refining-out station temperature until the requirements are met.

[0044] Furthermore, the temperature prediction model is: ; The measured temperature in this embodiment is 1550 °C, the temperature-rising speed of the molten steel at the fifth gear is 4 °C / min, the temperature drop of the furnace lining is -0.5 °C / min, the temperature drop of the furnace charge is -0.5 °C / min, the temperature drop during argon blowing is -1 °C / min, the temperature drop of the fume gas temperature is -0.5 °C / min, the time is 10 min, then the predicted temperature is 1565 °C.

[0045] Furthermore, increasing the heating time specifically means increasing the heating time by compressing the time of some operation processes.

[0046] The time of compressing some operation processes is usually to compress the soft blowing time, but the compression amplitude is limited by the molten steel composition, temperature, and the requirement for inclusion floating, and actual operation needs to be carried out according to the on-site process conditions.

[0047] In this embodiment, for example Figure 2As shown, the current heating gear is the fifth gear. The control flow chart after calling the temperature prediction model is as shown in the figure. If the fifth gear heating meets the heating requirement, maintain the fifth gear heating; otherwise, calculate whether the temperature prediction at the fourth gear meets the requirement. If it meets, adjust to the fourth gear heating; otherwise, compress the soft blowing time, increase the heating time by 5 minutes, and then determine whether the temperature prediction meets the requirement after the time increase. If it meets, adjust to the fourth gear heating; otherwise, give an alarm and switch to manual operation.

[0048] Furthermore, if increasing the heating gear and increasing the heating time still cannot make the predicted temperature of the molten steel reach the out-of-station requirement when both methods are used simultaneously, an automatic alarm will be given.

[0049] It should be noted that the present invention is not limited to the above embodiments. The above embodiments are only examples, and embodiments having the same constitution and the same effect as the technical idea within the technical solution scope of the present invention are all included in the technical scope of the present invention. In addition, within the scope not departing from the gist of the present invention, various modifications that those skilled in the art can think of to the embodiments, and other ways constructed by combining some constituent elements in the embodiments are also included in the scope of the present invention.

Claims

1. A rhythm adaptive refining time dynamic allocation method, characterized in that: The following steps are involved: Step 1: Based on the past continuous casting process data, a continuous casting remaining time prediction model is constructed. The formula is as follows: ； in: The remaining time for continuous casting; is the current weight of the continuous casting arm; To preset the weighing weight of the continuous casting arm when leaving the station; is the continuous casting section width; is the continuous casting section thickness; Real-time casting speed of the casting machine; is the density of molten steel; Step 2: at a critical time point of the current batch of molten steel refining, calling the continuous casting remaining time prediction model to predict the remaining time of the previous batch of molten steel continuous casting; Step 3: Obtaining the refining heating remaining time according to the continuous casting remaining time and the current batch remaining refining related operation time; Step 4: According to the current heating gear and the remaining refining heating time, adjust the remaining refining operation time to ensure that the heating time is sufficient and the target temperature is reached when the refining station is reached.

2. A rhythm adaptive refining time dynamic allocation method according to claim 1, characterized in that: The current weight of the continuous casting arm is calculated based on the weighing data of the support arm of the continuous casting turntable, and the arm weight less than 30 tons is used as the judgment condition for no bag.

3. A rhythm adaptive refining time dynamic allocation method according to claim 2, characterized in that: The current weight of the continuous casting arm, when the number of the continuous casting turntable arms is 2, is calculated as follows: Case 1: The weight of the first arm is less than 30 tons, and the weight of the second arm is greater than or equal to 30 tons, then the current weight of the continuous casting arm is equal to the weight of the second arm; Case 2: The weight of the second arm is less than 30 tons, and the weight of the first arm is greater than or equal to 30 tons, then the current weight of the continuous casting arm is equal to the weight of the first arm; Case 3: If the weight of the first arm and the second arm are both greater than or equal to 30 tons, the current weight of the continuous casting arm is equal to the sum of the two minus the empty bag weight corresponding to the arm with the smaller arm weight.

4. A rhythm adaptive refining time dynamic allocation method according to claim 1, characterized in that: The key time nodes of molten steel refining specifically include: temperature measurement at the refining station, the first temperature measurement after heating, and temperature measurement after desulfurization.

5. The method for dynamically allocating rhythm adaptive refining time according to claim 1, characterized in that: The remaining refining-related operation time includes at least one of the following: feeding time, wire feeding time, desulfurization time, soft blowing time, temperature measurement and sampling time, electrode lifting time, and reserved margin time.

6. A rhythm adaptive refining time dynamic allocation method according to claim 1, characterized in that: The step 4 specifically includes: calling the temperature prediction model, if the predicted temperature obtained by the current heating gear and the remaining refining heating time does not meet the refining outlet demand, then at least one of increasing the heating gear and increasing the heating time is used to increase the refining outlet temperature until the demand is met.

7. A rhythm adaptive refining time dynamic allocation method according to claim 6, characterized in that: The temperature prediction model is: ； in: Predicting temperature for molten steel; Measure the temperature of molten steel; It is the heating rate of molten steel at different gears; To reduce the temperature of the furnace lining; To reduce the charge temperature; Temperature drop for argon blowing; To reduce the flue gas temperature; is the time interval.

8. A rhythm adaptive refining time dynamic allocation method according to claim 6, characterized in that: The increasing the heating time specifically refers to increasing the heating time by compressing the time of part of the operation process.

9. A rhythm adaptive refining time dynamic allocation method according to claim 6, characterized in that: If the two methods of increasing the heating gear and increasing the heating time are used simultaneously and still cannot make the predicted temperature of the molten steel reach the outlet requirement, an automatic alarm will be given.

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