CN114918393B - Method for controlling periodic fluctuation of liquid level of medium-low carbon steel crystallizer - Google Patents
Method for controlling periodic fluctuation of liquid level of medium-low carbon steel crystallizer Download PDFInfo
- Publication number
- CN114918393B CN114918393B CN202210647009.6A CN202210647009A CN114918393B CN 114918393 B CN114918393 B CN 114918393B CN 202210647009 A CN202210647009 A CN 202210647009A CN 114918393 B CN114918393 B CN 114918393B
- Authority
- CN
- China
- Prior art keywords
- liquid level
- driving roller
- data
- current data
- crystallizer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000007788 liquid Substances 0.000 title claims abstract description 114
- 230000000737 periodic effect Effects 0.000 title claims abstract description 51
- 238000000034 method Methods 0.000 title claims abstract description 43
- 229910001209 Low-carbon steel Inorganic materials 0.000 title claims abstract description 32
- 230000001276 controlling effect Effects 0.000 claims abstract description 21
- 229910000954 Medium-carbon steel Inorganic materials 0.000 claims abstract description 18
- 230000001105 regulatory effect Effects 0.000 claims abstract description 18
- 238000012545 processing Methods 0.000 claims abstract description 13
- 238000009749 continuous casting Methods 0.000 claims description 29
- 238000004519 manufacturing process Methods 0.000 abstract description 27
- 238000005266 casting Methods 0.000 abstract description 26
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 16
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 14
- 229910000831 Steel Inorganic materials 0.000 description 12
- 238000004458 analytical method Methods 0.000 description 12
- 239000010959 steel Substances 0.000 description 12
- 230000008569 process Effects 0.000 description 10
- 229910052742 iron Inorganic materials 0.000 description 8
- 229910052786 argon Inorganic materials 0.000 description 7
- 238000003723 Smelting Methods 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- 238000002425 crystallisation Methods 0.000 description 4
- 230000008025 crystallization Effects 0.000 description 4
- 238000007670 refining Methods 0.000 description 4
- 230000006978 adaptation Effects 0.000 description 2
- 238000010219 correlation analysis Methods 0.000 description 2
- 238000007405 data analysis Methods 0.000 description 2
- 238000013480 data collection Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 230000033764 rhythmic process Effects 0.000 description 2
- 210000001015 abdomen Anatomy 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 230000003211 malignant effect Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/12—Accessories for subsequent treating or working cast stock in situ
- B22D11/1206—Accessories for subsequent treating or working cast stock in situ for plastic shaping of strands
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F16/00—Information retrieval; Database structures therefor; File system structures therefor
- G06F16/20—Information retrieval; Database structures therefor; File system structures therefor of structured data, e.g. relational data
- G06F16/28—Databases characterised by their database models, e.g. relational or object models
- G06F16/284—Relational databases
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]
Landscapes
- Engineering & Computer Science (AREA)
- Databases & Information Systems (AREA)
- Mechanical Engineering (AREA)
- Theoretical Computer Science (AREA)
- Data Mining & Analysis (AREA)
- Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Continuous Casting (AREA)
Abstract
The invention discloses a method for controlling periodic fluctuation of liquid level of a medium-carbon steel crystallizer and a low-carbon steel crystallizer, which comprises the following steps: acquiring liquid level data of the crystallizer and current data of each driving roller, and carrying out differential processing on the liquid level data and the current data; when the fluctuation value of the liquid level data exceeds a preset fluctuation value, determining a target driving roller, wherein the fluctuation trend of the current data of the target driving roller is the same as that of the liquid level data; calculating the correlation coefficient of the current data of each driving roller and the current data of the target driving roller, and determining the driving roller to be regulated, wherein the correlation coefficient of the current data of the driving roller to be regulated is more than or equal to a preset coefficient; and reducing the roll gap of the sector section where the driving roll to be adjusted is positioned by a preset distance. According to the method provided by the invention, the problem of periodic liquid level fluctuation of the crystallizer is solved by accurately finding the sector-shaped section position of the unstable casting blank bulging which induces the periodic fluctuation of the liquid level of the crystallizer, and the production and product quality are stabilized under the condition of not increasing the cost.
Description
Technical Field
The invention relates to the technical field of steelmaking continuous casting, in particular to a method for controlling periodic fluctuation of liquid level of a medium-carbon steel crystallizer and a low-carbon steel crystallizer.
Background
Mechanism of periodic fluctuation of the crystallizer liquid level: when the continuous casting machine with liquid core is used for producing, the hydrostatic pressure of molten steel generates bellying force between continuous casting rollers to make casting blank generate bellying phenomenon, and the bellying amount is controlled at the design time of the continuous casting machine roller rowWithin the inner part. The casting blank with the belly is compressed by the next pair of guide rollers in the advancing process, and is bulged out after leaving the pair of guide rollers, and the process is continuously carried out among a plurality of guide rollers in the secondary cooling area. If the process is carried out uniformly and continuously and the blank shell mainly shows plastic deformation, the circular arc-shaped bulging between the two guide rollers is symmetrical. The liquid core volume of the casting blank in the fan-shaped section is kept unchanged or basically unchanged at any moment, and the liquid level of the steel in the crystallizer is stable and does not generate liquid level periodic fluctuation. When the blank shell is not symmetrical, the bulge and pressing back process of the bulge between the two guide rollers is continuous but uneven, and the liquid cavity volume and the force applied to the guide rollers are changed at any time. If the distances between the guide rollers of the fan-shaped sections are equal (or similar), the liquid cavity changes among the guide rollers can be synchronously carried out, the liquid cavity changes among the guide rollers are overlapped, large crystallizer liquid level fluctuation is generated, and a certain rhythm, namely periodicity, is presented. The period of one liquid level fluctuation is the time between the casting blank passing through the two pairs of guide rollers. Crystallizer periodic level fluctuation definition: when unstable bulging occurs in the molten steel volume in the liquid core of the casting flow below the crystallizer, namely the molten steel volume is greatly changed, and the volume changes cannot be mutually counteracted in the casting flow, the volume changes are reflected to the mechanical behavior that the crystallizer becomes periodic fluctuation of the liquid level.
A great deal of research is carried out on periodic fluctuation of the liquid level of the crystallizer at home and abroad, and the research shows that the root cause is unstable bulging of the casting blank in the sector section, and the fluctuation period is in direct proportion to the roller spacing of continuous casting.
In the prior art, the technical scheme (one): using different roller spacing to restrain periodic liquid level fluctuation; on a sheet billet continuous casting machine, a variable continuous casting roll gap technology is applied to control the periodic fluctuation of the liquid level of a crystallizer, so that the record of the continuous casting pulling speed of the sheet billet is created; or the problem of periodic liquid level fluctuation is thoroughly solved by changing the continuous casting roller row; the technical scheme (II) is as follows: by increasing the water quantity of the crystallizer, the secondary cooling water quantity, the mold flux and the pressure of the driving roller, the stopper rod controls the flow, and the problem of periodic fluctuation of the liquid level of the crystallizer caused by unstable bulging in the continuous casting process is solved.
However, for the technical scheme (I), the continuous casting equipment needs to be greatly modified, the investment of equipment of tens of millions or even hundreds of millions is huge, the equipment manufacturing period is long, and a production factory needs to invest a great deal of manpower, material resources and sacrifice production time to modify the equipment; for the technical scheme (II), the continuous casting process and the flow control system are adjusted to compensate the periodical fluctuation of the liquid level of the crystallizer caused by unstable bulging, so that the process cost is increased, and the real problem of unstable bulging in the continuous casting production process is not really found.
Therefore, how to effectively solve the problem of periodic liquid level fluctuation of the crystallizer is a technical problem which needs to be solved by the person skilled in the art at present.
Disclosure of Invention
The invention aims to provide a method for controlling periodic fluctuation of liquid level of a medium-low carbon steel crystallizer, which is used for eliminating the problem of periodic fluctuation of liquid level of the crystallizer and stabilizing production and product quality.
In order to achieve the above purpose, the present invention provides the following technical solutions:
a method for controlling periodic fluctuation of liquid level of a medium-carbon steel crystallizer and a low-carbon steel crystallizer, which comprises the following steps:
Step S1: acquiring liquid level data of a crystallizer and current data of each driving roller, and carrying out differential processing on the liquid level data and the current data;
step S2: when the fluctuation value of the liquid level data exceeds a preset fluctuation value, determining a target driving roller, wherein the fluctuation trend of the current data of the target driving roller is the same as that of the liquid level data;
step S3: calculating the correlation coefficient of the current data of each driving roller and the current data of the target driving roller, and determining the driving roller to be regulated, wherein the correlation coefficient of the current data of the driving roller to be regulated is more than or equal to a preset coefficient;
step S4: and reducing the roll gap of the sector section where the driving roll to be adjusted is positioned by a preset distance.
Preferably, the step S4 includes:
And reducing the preset distance between the inlet roll gap and the outlet roll gap of the sector section where the driving roller to be regulated is positioned by remote control.
Preferably, in the step S2, the preset fluctuation value is ±3mm.
Preferably, in the step S3, the preset coefficient is 0.8.
Preferably, in the step S4, the preset distance is 0.3-0.5mm.
Preferably, in step S1, the data collection of the liquid level data and the current data uses OPC protocol to collect data from the continuous casting primary base automation system.
Preferably, the step S1 further includes:
And storing the collected liquid level data and the collected current data by combining two databases of MySQL and InfluxDB.
Preferably, before the step S1, the method further includes: determining the number of the sector sections and marking according to the sequence of each sector section;
the step S1 includes:
acquiring liquid level data of a crystallizer, and performing differential processing on the liquid level data according to a formula (1);
DeltaS t＝St-S(t-1) formula (1)
Wherein S t represents the liquid level data of the crystallizer at the moment t;
Acquiring current data of each driving roller, and performing differential processing on the current data according to a formula (2);
ΔI3t＝I3t-I(3t-1)
ΔI 4t＝I4t-I(4t-1) formula (2)
......
Wherein I 3t represents the current data of the driving roller at the time t in the third sector; i 4t represents the current data of the drive roller at time t in the fourth segment.
Preferably, in the step S3, the correlation coefficient is calculated by the formula (3):
......
Wherein corr represents a correlation coefficient; i 3 represents the current data of the drive roller in the third segment; i 4 represents the current data of the drive roller in the fourth segment; i 5 represents the current data of the drive roller in the fifth segment.
The method for controlling the periodic fluctuation of the liquid level of the medium-carbon steel crystallizer and the low-carbon steel crystallizer provided by the invention comprises the following steps: step S1: acquiring liquid level data of a crystallizer and current data of each driving roller, and carrying out differential processing on the liquid level data and the current data; step S2: when the fluctuation value of the liquid level data exceeds a preset fluctuation value, determining a target driving roller, wherein the fluctuation trend of the current data of the target driving roller is the same as that of the liquid level data; step S3: calculating the correlation coefficient of the current data of each driving roller and the current data of the target driving roller, and determining the driving roller to be regulated, wherein the correlation coefficient of the current data of the driving roller to be regulated is more than or equal to a preset coefficient; step S4: and reducing the roll gap of the sector section where the driving roll to be adjusted is positioned by a preset distance. According to the method for controlling the periodic fluctuation of the liquid level of the medium-low carbon steel crystallizer, provided by the invention, the position of the sector section of the unstable casting blank bulging which induces the periodic fluctuation of the liquid level of the crystallizer is accurately found, and the sector section is regulated by the remote roll gap, so that the problem of the periodic fluctuation of the liquid level of the crystallizer is solved under the condition of not increasing the cost, and the production and the product quality are stabilized.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a differential data comparison of low carbon steel crystallizer level and drive roller current;
FIG. 2 is a correlation coefficient analysis of each drive roller when the crystallizer level periodically fluctuates with low carbon steel;
FIG. 3 shows the fluctuation of the crystallization level before and after adjustment of the low carbon steel;
FIG. 4 is a correlation coefficient analysis of the low carbon steel for each drive roller after adjustment of the roll gap at the unstable position;
FIG. 5 is a differential data comparison of medium carbon steel crystallizer level and drive roller current;
FIG. 6 is a correlation coefficient analysis of each drive roller when periodic liquid level fluctuations occur in medium carbon steel;
FIG. 7 is a correlation coefficient analysis of the drive rollers after the medium carbon steel is adjusted for the roll gap at the unstable position;
FIG. 8 shows the roll gap measurements for each segment of the caster after production;
FIG. 9 is a flow chart of one embodiment of a method for controlling periodic fluctuations in the liquid level of a mild steel crystallizer according to the present invention.
Detailed Description
The core of the invention is to provide a method for controlling the periodic fluctuation of the liquid level of a medium-carbon steel crystallizer and a low-carbon steel crystallizer, which can eliminate the problem of the periodic fluctuation of the liquid level of the crystallizer and stabilize the production and the product quality.
In order to better understand the aspects of the present invention, the present invention will be described in further detail with reference to the accompanying drawings and detailed description.
Referring to fig. 1 to 9, fig. 1 is a differential data comparison of the low carbon steel crystallizer level and the drive roller current; FIG. 2 is a correlation coefficient analysis of each drive roller when the crystallizer level periodically fluctuates with low carbon steel; FIG. 3 shows the fluctuation of the crystallization level before and after adjustment of the low carbon steel; FIG. 4 is a correlation coefficient analysis of the low carbon steel for each drive roller after adjustment of the roll gap at the unstable position; FIG. 5 is a differential data comparison of medium carbon steel crystallizer level and drive roller current; FIG. 6 is a correlation coefficient analysis of each drive roller when periodic liquid level fluctuations occur in medium carbon steel; FIG. 7 is a correlation coefficient analysis of the drive rollers after the medium carbon steel is adjusted for the roll gap at the unstable position; FIG. 8 shows the roll gap measurements for each segment of the caster after production; FIG. 9 is a flow chart of one embodiment of a method for controlling periodic fluctuations in the liquid level of a mild steel crystallizer according to the present invention.
In this embodiment, the method of controlling periodic fluctuations in the liquid level of a medium and low carbon steel crystallizer comprises the steps of:
step S1: acquiring liquid level data of the crystallizer and current data of each driving roller, carrying out differential processing on the liquid level data and the current data, and acquiring fluctuation trend of the liquid level data and fluctuation trend of the current data through differential processing;
step S2: when the fluctuation value of the liquid level data exceeds a preset fluctuation value, determining a target driving roller, wherein the fluctuation trend of the current data of the target driving roller is the same as that of the liquid level data; specifically, when the fluctuation value of the liquid level data exceeds a preset fluctuation value, a driving roller consistent with the fluctuation trend of the liquid level data is found out and used as a target driving roller;
Step S3: calculating the correlation coefficient of the current data of each driving roller and the current data of the target driving roller, determining the driving roller to be regulated, wherein the correlation coefficient of the current data of the driving roller to be regulated is more than or equal to a preset coefficient, and using the correlation coefficient as a selection principle of the driving roller to be regulated can accurately solve the problem of periodic liquid level fluctuation of the crystallizer;
step S4: the roll gap of the sector section where the driving roller to be adjusted is reduced by a preset distance, and the problem of unstable casting blank bulging is solved by adjusting the roll gap of the sector section where the driving roller to be adjusted is located.
According to the method for controlling the periodic fluctuation of the liquid level of the medium-low carbon steel crystallizer, provided by the invention, the position of the sector section of the unstable casting blank bulging which induces the periodic fluctuation of the liquid level of the crystallizer is accurately found, and the sector section is regulated by the remote roll gap, so that the problem of the periodic fluctuation of the liquid level of the crystallizer is solved under the condition of not increasing the cost, and the production and the product quality are stabilized.
In addition to the above embodiments, step S4 includes:
Reducing preset distances between an inlet roll gap and an outlet roll gap of a sector section where a driving roller to be regulated is positioned by remote control; remote control is adopted, so that the operation is convenient.
On the basis of the above embodiments, in step S2, the preset fluctuation value is ±3mm. In particular, since the periodic fluctuation of the liquid level of the continuous casting crystallizer in the production flow of steel has important harm to the quality and production of casting blanks: in the continuous casting production process, the fluctuation of the liquid level of the crystallizer is required to be controlled within +/-5 mm, and if the fluctuation exceeds the control range, periodic fluctuation occurs; the temperature and flow field of the crystallizer are damaged, and casting blank surface defects of slag rolling and cracks are generated; the continuous casting pulling speed is forced to be reduced, the normal production rhythm of a steel mill is destroyed, and even malignant accidents such as steel leakage and the like are generated, so that the preset fluctuation value is set to be +/-3 mm.
In step S3, the preset coefficient is 0.8, based on the above embodiments.
Based on the above embodiments, in step S4, the preset distance is 0.3-0.5mm, and the preset distance may be set according to the actual type of the continuous casting machine, where the preset distance should not be too large, resulting in serious equipment wear, and the preset distance should not be too small, so that the effect of improving the bulging effect of the unstable casting blank is not obvious. Specifically, through data analysis, the position of the fan-shaped section of the unstable casting blank bulging which induces the periodical fluctuation of the liquid level of the crystallizer is accurately found, and the inlet and outlet roll gaps of the fan-shaped section are simultaneously reduced by 0.3-0.5mm through remote roll gap adjustment on the fan-shaped section, so that the periodical fluctuation problem of the liquid level of the crystallizer can be eliminated.
Preferably, in step S1, the data collection of the liquid level data and the current data uses OPC protocol to collect data from the continuous casting primary basic automation system. Preferably, step S1 further includes: and storing the collected liquid level data and the collected current data by combining two databases of MySQL and InfluxDB. Specifically, the data acquisition adopts an OPC protocol to acquire data from a continuous casting primary basic automation system, and the acquired data has the characteristics of high frequency, large data volume and the like; the two databases MySQL and InfluxDB are combined, high-frequency massive historical data is stored, and the query speed is high.
In addition to the above embodiments, before step S1, the method further includes: the method comprises the steps of determining the number of the sector sections, marking according to the sequence of each sector section, wherein a target driving roller is positioned in the target sector section, and a driving roller to be regulated is positioned in the sector section to be regulated, wherein each sector section consists of a plurality of pairs of rollers, such as 7 pairs of rollers, and the driving roller is a middle pair of rollers; specifically, taking a continuous casting machine with 11 fan-shaped sections as an example, carrying out differential data processing on the collected liquid level data of the crystallizer, wherein 9 fan-shaped sections SEG 3-SEG 11 are totally processed according to the current data of the upper roller and the lower roller; of course, for continuous casters with different numbers of drive rolls, the segments can be selected as the case may be.
Further, step S1 includes:
Acquiring liquid level data of a crystallizer, and performing differential processing on the liquid level data according to a formula (1);
DeltaS t＝St-S(t-1) formula (1)
Wherein S t represents the liquid level data of the crystallizer at the moment t;
acquiring current data of each driving roller, and carrying out differential processing on the current data according to a formula (2);
ΔI3t＝I3t-I(3t-1)
ΔI 4t＝I4t-I(4t-1) formula (2)
......
Wherein I 3t represents the current data of the driving roller at the time t in the third sector; i 4t represents the current data of the drive roller at time t in the fourth segment.
In step S3, the correlation coefficient is calculated by the formula (3):
......
Wherein corr represents a correlation coefficient; i 3 represents the current data of the drive roller in the third segment; i 4 represents the current data of the drive roller in the fourth segment; i 5 represents the current data of the drive roller in the fifth segment.
Specifically, the production process comprises the following steps:
Pouring, molten iron pretreatment, converter smelting, argon station, conventional slab continuous casting and finishing;
Or pouring, molten iron pretreatment, converter smelting, argon station, refining (LF furnace or RH furnace), conventional slab continuous casting and finishing;
The molten steel comprises the following components:
the molten iron is turned over by a back-pouring station, desulphurized, deslagged, smelted by a converter, refined and adjusted in composition and temperature by an argon station and refining in a molten iron pretreatment process, and conveyed to slab continuous casting for casting. The composition control was performed as required in table 1.
TABLE 1 molten steel composition
Specifically, through analyzing the difference data of the liquid level data and the current data of the crystallizer, when the fluctuation of the liquid level data of the crystallizer exceeds +/-3 mm and the fluctuation is periodic, comparing whether the fluctuation condition of the same trend exists in the current of each driving roller, if so, indicating that the unstable casting blank bulging condition exists in the sector section corresponding to the driving roller.
And carrying out correlation analysis on the currents of all the driving rollers of the SEG 3-SEG 11, and finding out the driving roller with the similar or high consistency of the current correlation coefficient of the driving roller with large current difference data fluctuation, wherein the sector section where the driving roller is positioned is the unstable bulging position of the casting blank.
According to the method provided by the invention, through rapid acquisition of the crystallizer liquid level data and the current data of each driving roller, and the method of data differential analysis and data comparison, the periodic fluctuation of the crystallizer liquid level data is found in time, and whether the unstable bulging condition of a casting blank exists is judged; accurately finding the position of the bulging sector section of the unstable casting blank which induces the periodical fluctuation of the liquid level of the crystallizer by a correlation coefficient analysis method of the current data of each driving roller; the method for eliminating the periodical fluctuation of the liquid level of the crystallizer by controlling the long-distance roll gap and adjusting the roll gap of the inlet and outlet of the sector section on line in the production process.
Example 1
1) The process flow is as follows: pouring, molten iron pretreatment, converter smelting, an argon station, conventional slab continuous casting, finishing or pouring, molten iron pretreatment, converter smelting, an argon station, refining (LF furnace or RH furnace), conventional slab continuous casting, finishing production of low-carbon steel, and the actual compositions are shown in Table 2:
TABLE 2 molten steel composition of example 1
| Steel grade | C％(2) | Si％(2) | Mn％(2) | P％(3) | S％(3) | Als％(3) |
| Low carbon steel | 0.04 | 0.02 | 0.25 | 0.020 | 0.018 | 0.040 |
2) The crystallizer liquid level fluctuation occurs in the continuous slab casting production process, and the trend of the current difference data of the SEG5 section driving roller is found to be highly consistent with the trend of the crystallizer liquid level data difference data through the comparison of the crystallizer liquid level data and the driving roller current data of the data acquisition system. As shown in fig. 1.
3) The drive currents of the SEG4 segment and the S4G6 segment, which have very high correlation coefficients with the SEG5 segment drive roller currents, reach +0.84 and +0.88, respectively, as shown in fig. 2.
4) According to the analysis result, judging that unstable bulging occurs in the SEG4 section and the SEG6 section in the production process, and carrying out online adjustment on the inlet and outlet roll gaps of the SEG4 section and the SEG6 section, respectively reducing the roll gaps by 0.3mm, thereby effectively eliminating the periodical fluctuation condition of the liquid level of the crystallizer; there is a large amplitude of periodic fluctuations in the crystallizer liquid level prior to adjustment. The maximum fluctuation range exceeds more than 15mm, the large-amplitude periodic fluctuation of the crystallization liquid level is eliminated after adjustment, and the control range of the liquid level precision of the crystallizer is all within +/-5 mm. And the current correlation coefficient of each driving roller is analyzed, and the situation of unstable casting blank bulging does not exist. As shown in fig. 3 and 4.
Example 2
1) The method comprises the following steps of pouring ladle, molten iron pretreatment, converter smelting, argon station, conventional slab continuous casting, finishing or pouring ladle, molten iron pretreatment, converter smelting, argon station, refining (LF furnace or RH furnace), conventional slab continuous casting and finishing production of low-carbon steel, wherein the actual components are as follows:
TABLE 3 molten steel composition of example 2
2) The crystallizer liquid level fluctuation occurs in the continuous slab casting production process, and the comparison of the crystallizer liquid level data and the driving roller current data through the data acquisition system shows that the current difference data of the SEG6 section driving roller is highly consistent with the crystallizer liquid level difference data. As shown in fig. 5.
3) Correlation analysis is carried out on the current of each drive, and the data analysis shows that: the very high correlation coefficient with the SEG6 segment drive roller current is the SEG5 segment drive roller current, which correlates to +0.92, respectively, as shown in fig. 6.
4) According to the analysis result, judging that unstable bulging occurs in the SEG5 section in the production process, carrying out online adjustment on the inlet and outlet roll gaps of the SEG5 section, respectively reducing the thickness by 0.5mm, eliminating large-amplitude periodic fluctuation of the crystallization liquid level after adjustment, analyzing the current correlation coefficient of each driving roller, and eliminating the unstable bulging condition of casting blanks. After the production is finished, the roll gaps of all the sector sections of the casting machine are measured, the actual roll gap of the SEG5 section exceeds the control standard and is larger, the method is proved to be capable of accurately analyzing the sector section position of the unstable bulging in the production process, and the periodical fluctuation problem of the liquid level of the crystallizer is eliminated by adjusting the roll gaps of the sector sections, as shown in fig. 7 and 8.
The method for controlling the periodic fluctuation of the liquid level of the medium-carbon steel crystallizer and the low-carbon steel crystallizer has the following advantages:
1) The investment of equipment reconstruction funds is not increased;
2) The cost investment of the process and auxiliary materials is not increased;
3) Judging the position of a bulging fan-shaped section of the unstable casting blank, which induces periodic fluctuation of the liquid level of the crystallizer, in the production process;
4) The simple and quick control method effectively eliminates the periodic fluctuation of the liquid level of the crystallizer;
5) The product quality is stabilized, and the smooth production is ensured.
The method for controlling the periodic fluctuation of the liquid level of the medium-carbon steel crystallizer and the low-carbon steel crystallizer provided by the invention is described in detail. The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to facilitate an understanding of the method of the present invention and its core ideas. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the invention can be made without departing from the principles of the invention and these modifications and adaptations are intended to be within the scope of the invention as defined in the following claims.
Claims (6)
1. A method for controlling periodic fluctuation of liquid level of a medium-carbon steel crystallizer and a low-carbon steel crystallizer, which is characterized by comprising the following steps:
Step S1: acquiring liquid level data of a crystallizer and current data of each driving roller, and carrying out differential processing on the liquid level data and the current data;
step S2: when the fluctuation value of the liquid level data exceeds a preset fluctuation value, determining a target driving roller, wherein the fluctuation trend of the current data of the target driving roller is the same as that of the liquid level data;
step S3: calculating the correlation coefficient of the current data of each driving roller and the current data of the target driving roller, and determining the driving roller to be regulated, wherein the correlation coefficient of the current data of the driving roller to be regulated is more than or equal to a preset coefficient;
step S4: reducing the roll gap of the sector section where the driving roll to be adjusted is located by a preset distance;
Before the step S1, the method further includes: determining the number of the sector sections and marking according to the sequence of each sector section;
the step S1 includes:
acquiring liquid level data of a crystallizer, and performing differential processing on the liquid level data according to a formula (1);
DeltaS t＝St-S(t-1) equation (1)
Wherein S t represents the liquid level data of the crystallizer at the moment t;
Acquiring current data of each driving roller, and performing differential processing on the current data according to a formula (2);
Wherein I 3t represents the current data of the driving roller at the time t in the third sector; i 4t represents the current data of the driving roller at time t in the fourth segment;
In the step S3, the correlation coefficient is calculated by the formula (3):
......
Wherein corr represents a correlation coefficient; i 3 represents the current data of the drive roller in the third segment; i 4 represents the current data of the drive roller in the fourth segment; i 5 represents the current data of the drive roller in the fifth segment;
The step S4 includes:
And reducing the gap between the inlet roller and the outlet roller of the driving roller to be regulated by a preset distance through remote control.
2. The method for controlling periodic fluctuation of liquid level in a medium-low carbon steel crystallizer according to claim 1, wherein in the step S2, the preset fluctuation value is ±3mm.
3. The method for controlling periodic fluctuation of liquid level in a medium and low carbon steel crystallizer according to claim 1, wherein the preset coefficient is 0.8 in the step S3.
4. The method for controlling periodic fluctuation of liquid level in a medium and low carbon steel crystallizer according to claim 1, wherein in the step S4, the preset distance is 0.3-0.5mm.
5. The method for controlling periodic fluctuation of liquid level in a medium-low carbon steel crystallizer according to claim 1, wherein in the step S1, data acquisition of the liquid level data and the current data adopts OPC protocol to acquire data from a continuous casting primary basic automation system.
6. The method for controlling periodic fluctuation of liquid level in a medium and low carbon steel crystallizer according to claim 5,
The step S1 further includes:
And storing the collected liquid level data and the collected current data by combining two databases of MySQL and InfluxDB.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210647009.6A CN114918393B (en) | 2022-06-09 | 2022-06-09 | Method for controlling periodic fluctuation of liquid level of medium-low carbon steel crystallizer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210647009.6A CN114918393B (en) | 2022-06-09 | 2022-06-09 | Method for controlling periodic fluctuation of liquid level of medium-low carbon steel crystallizer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114918393A CN114918393A (en) | 2022-08-19 |
| CN114918393B true CN114918393B (en) | 2024-07-19 |
Family
ID=82811998
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210647009.6A Active CN114918393B (en) | 2022-06-09 | 2022-06-09 | Method for controlling periodic fluctuation of liquid level of medium-low carbon steel crystallizer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114918393B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101081428A (en) * | 2007-05-15 | 2007-12-05 | 武汉钢铁(集团)公司 | Method for preventing liquid fluctuating of continuous casting peritectic steel crystallizer |
| CN109034665A (en) * | 2018-09-03 | 2018-12-18 | 中冶连铸技术工程有限责任公司 | A kind of continuous casting billet process data course information tracking method |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3907905C2 (en) * | 1988-07-04 | 1999-01-21 | Mannesmann Ag | Continuous casting process |
| IT1259778B (en) * | 1992-05-27 | 1996-03-26 | Danieli Off Mecc | RING LATERAL CONTAINMENT DEVICE FOR CONTINUOUS ROLLER CASTING PLANTS |
| DE19720768C1 (en) * | 1997-05-07 | 1999-01-14 | Mannesmann Ag | Method and device for producing steel slabs |
| JP2005118803A (en) * | 2003-10-15 | 2005-05-12 | Toyota Motor Corp | Metal sheet manufacturing apparatus and manufacturing method |
| JP2007260693A (en) * | 2006-03-27 | 2007-10-11 | Jfe Steel Kk | Method for controlling in-mold molten metal surface level in continuous casting machine |
| CN101920316B (en) * | 2010-08-03 | 2015-08-19 | 中国重型机械研究院有限公司 | A kind of method for reforming continuous casting machine solving liquid level fluctuation of crystallizer |
| CN105436204B (en) * | 2016-01-10 | 2017-08-08 | 东北大学 | The rolling device and its method of a kind of high silicon steel |
| AT519390B1 (en) * | 2016-12-13 | 2020-09-15 | Primetals Technologies Austria GmbH | Method and device for controlling a continuous caster |
| CN111679625B (en) * | 2020-06-29 | 2021-10-29 | 马鞍山钢铁股份有限公司 | Method for evaluating liquid level fluctuation of multi-dimensional continuous casting machine crystallizer quickly and accurately |
| CN113145816B (en) * | 2021-01-28 | 2022-11-18 | 吉林建龙钢铁有限责任公司 | Control method for reducing medium carbon steel structure defects |
| CN113137211B (en) * | 2021-04-02 | 2023-01-17 | 常州大学 | A self-adaptive control method of oil well production parameters based on fuzzy comprehensive decision-making |
-
2022
- 2022-06-09 CN CN202210647009.6A patent/CN114918393B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101081428A (en) * | 2007-05-15 | 2007-12-05 | 武汉钢铁(集团)公司 | Method for preventing liquid fluctuating of continuous casting peritectic steel crystallizer |
| CN109034665A (en) * | 2018-09-03 | 2018-12-18 | 中冶连铸技术工程有限责任公司 | A kind of continuous casting billet process data course information tracking method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114918393A (en) | 2022-08-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102451838B (en) | Method for overcoming camber defect in hot rolling process of steel plate | |
| EP2818259B1 (en) | Pre-control method of head and tail shapes of continuous casting slab for reducing the removed amount from the head and tail of hot-rolled intermediate slab | |
| CN102756013B (en) | Improving method and device for warping of cold-rolled strip steel | |
| CN110523942B (en) | Control method for improving internal defects of high-carbon chromium bearing steel bloom | |
| CN111360221B (en) | Method for eliminating central shrinkage cavity and controlling central segregation of high-carbon steel with 280mm x 320mm section | |
| CN110396648A (en) | A kind of special thick alloy mold steel plate of continuous casting billet production and its manufacturing method | |
| CN100352570C (en) | Rolling method for overcoming compound wave shape | |
| CN109711113B (en) | A Method for Predicting Segregation Behavior of Bloom Convex Roll Continuous Casting under Heavy Pressure | |
| CN1132707C (en) | Method and device for operating a continuous casting plant | |
| CN114918393B (en) | Method for controlling periodic fluctuation of liquid level of medium-low carbon steel crystallizer | |
| CN111872131B (en) | Method for dynamically adjusting emulsion flow of cold continuous rolling mill | |
| CN113500100B (en) | Roll gap control method based on mechanical parameters on rolling contact interface segmentation model | |
| JPH08132203A (en) | Continuous casting method | |
| CN111687388B (en) | A method for improving the stability of the roll gap in the sector of a slab continuous caster | |
| CN1596163A (en) | Method for continuous foundry | |
| CN107790662B (en) | Method and device for controlling center segregation of plate blank | |
| CN114393044B (en) | Wide and thick plate shape buckling and plate convexity control method | |
| CN113732844A (en) | Method and device for grinding work roll | |
| CN118527607B (en) | A method for improving edge pit defects of thin strip steel | |
| CN114669723B (en) | Control method for effective rolling interval of casting blank | |
| CN117443946A (en) | Method for controlling bending defect of hot-rolled intermediate billet | |
| CN201664707U (en) | Guide mechanism used for up-jet laminar flow cooling device | |
| CN118045872A (en) | Rough rolling intermediate billet convexity prediction method based on actual measurement abrasion of working roll | |
| SU703227A1 (en) | Method of continuous casting of metals | |
| CN118904899A (en) | Rectangular flat steel hole pattern design and rolling process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |