CN112517867A - Optimized arrangement method of flat nozzles for continuous casting - Google Patents
Optimized arrangement method of flat nozzles for continuous casting Download PDFInfo
- Publication number
- CN112517867A CN112517867A CN202011357932.3A CN202011357932A CN112517867A CN 112517867 A CN112517867 A CN 112517867A CN 202011357932 A CN202011357932 A CN 202011357932A CN 112517867 A CN112517867 A CN 112517867A
- Authority
- CN
- China
- Prior art keywords
- nozzle
- nozzles
- water quantity
- continuous casting
- height
- 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.)
- Granted
Links
Images
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
- B22D11/12—Accessories for subsequent treating or working cast stock in situ
- B22D11/124—Accessories for subsequent treating or working cast stock in situ for cooling
- B22D11/1246—Nozzles; Spray heads
-
- 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
- B22D11/22—Controlling or regulating processes or operations for cooling cast stock or mould
- B22D11/225—Controlling or regulating processes or operations for cooling cast stock or mould for secondary cooling
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/17—Mechanical parametric or variational design
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q10/00—Administration; Management
- G06Q10/06—Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
- G06Q10/063—Operations research, analysis or management
- G06Q10/0639—Performance analysis of employees; Performance analysis of enterprise or organisation operations
- G06Q10/06393—Score-carding, benchmarking or key performance indicator [KPI] analysis
Landscapes
- Engineering & Computer Science (AREA)
- Business, Economics & Management (AREA)
- Physics & Mathematics (AREA)
- Human Resources & Organizations (AREA)
- Theoretical Computer Science (AREA)
- Geometry (AREA)
- General Physics & Mathematics (AREA)
- Entrepreneurship & Innovation (AREA)
- Strategic Management (AREA)
- Mechanical Engineering (AREA)
- Economics (AREA)
- Educational Administration (AREA)
- Development Economics (AREA)
- Game Theory and Decision Science (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- General Engineering & Computer Science (AREA)
- Evolutionary Computation (AREA)
- Computer Hardware Design (AREA)
- Computational Mathematics (AREA)
- Pure & Applied Mathematics (AREA)
- Quality & Reliability (AREA)
- Operations Research (AREA)
- Marketing (AREA)
- Tourism & Hospitality (AREA)
- General Business, Economics & Management (AREA)
- Continuous Casting (AREA)
Abstract
A method for optimizing the arrangement of flat nozzles for continuous casting, comprising the steps of: a. determining a working pressure set value of the nozzle; b. carrying out water distribution test on the single nozzle; c. determining the metering width of the water quantity; d. calculating the water quantity ratio of the spraying overlapping area of the adjacent nozzles to the central area of the single nozzle; e. calculating the water quantity ratio of the edge area to the central area when the heights of the nozzles are different and the distances between the nozzles are different; f. and determining the optimal arrangement mode of the nozzles. The invention is based on the cold state performance test of the nozzle, and combines the actual continuous casting process data to determine the optimal configuration method of the nozzle under different working conditions. The method is simple and easy to implement, the obtained nozzle configuration scheme has high conformity with the actual continuous casting process, the transverse cooling uniformity of the continuous casting billet can be improved, the occurrence probability of quality defects such as cracks, bulging and the like of the continuous casting billet is reduced, and the quality of the continuous casting billet is improved.
Description
Technical Field
The invention relates to a method for optimizing the arrangement of a flat nozzle for continuous casting, and belongs to the technical field of metallurgical equipment.
Background
In the continuous casting production process, the cooling mechanism of the secondary cooling zone has important influence on the quality of the continuous casting billet, and whether the continuous casting billet can be cooled more uniformly in the secondary cooling zone directly influences the occurrence probability of the defects of cracks, bulging and the like. In the secondary cooling area, the heat taken away by the cooling water sprayed by the nozzle accounts for more than 50% of the total heat dissipation of the secondary cooling area, and is the main heat transfer mode of the cooling section, so the selection and arrangement mode of the nozzle type directly influences the cooling effect of the continuous casting billet in the secondary cooling area.
The nozzles for continuous casting are generally divided into two types, i.e., water nozzles and gas-water atomizing nozzles, and the shapes of the nozzle jet flow include flat, conical, elliptical and rectangular. The nozzle types are different, the arrangement modes matched with the nozzle types are different, the optimal arrangement modes of the nozzles of various types under different working environments are determined, and the method has important practical significance for improving the cooling uniformity of the continuous casting billet in the secondary cooling zone. At present, reports on improving the cooling uniformity of a secondary cooling zone mainly reflect that a corresponding secondary cooling water distribution and nozzle arrangement mode optimization scheme is established for a specific steel grade or a continuous casting machine, so that the proposed scheme has limited applicability; in addition, the research of the combination of the formulation of the optimization scheme and the cold state performance of the nozzle is less, and the cooling uniformity of the continuous casting billet in the secondary cooling zone cannot be ensured, so that further research needs to be carried out.
Disclosure of Invention
The invention aims to provide an optimal arrangement method of flat nozzles for continuous casting, aiming at overcoming the defects of the prior art, so as to improve the cooling uniformity of a continuous casting billet in a secondary cooling zone and reduce the occurrence probability of quality defects of the continuous casting billet.
The problems of the invention are solved by the following technical scheme:
a method for optimizing the arrangement of flat nozzles for continuous casting, comprising the steps of:
a. determining a working pressure set value of the nozzle;
b. water distribution test on single nozzle
Setting the height of a nozzle of a continuous casting machine as an initial height h, setting the water inlet pressure as a working pressure set value, carrying out water distribution test on single nozzles of different models by adopting spray detection equipment, and recording a single-nozzle spray angle theta, a spray coverage width D and water distribution data within the spray coverage width range;
c. determining the metering width of the water quantity
Calculating the width d' of the spraying overlapping area of the adjacent nozzles:
d′＝D–d
wherein d is the distance between two adjacent nozzles, and the calculated width d' of the spraying overlapping area of the adjacent nozzles is used as the metering width of the water quantity;
d. calculating the water quantity ratio lambda of the spraying overlapping area of the adjacent nozzles to the central area of the single nozzle:
according to the water distribution data in the spray coverage width range of the nozzles, calculating the ratio ξ of the water quantity in the metering width range right below the single nozzle and the total water quantity of the single nozzle, and the ratio η of the water quantity in the metering width range of the edge region of the spray coverage range of the single nozzle and the total water quantity of the single nozzle, so that the water quantity ratio of the spray overlapping region of the adjacent nozzles and the central region of the single nozzle is as follows:
λ＝2η/ξ；
e. calculating the ratio of water amount in the edge area to water amount in the center area at different nozzle heights and different nozzle pitches
Firstly, calculating the water quantity ratio of the edge area to the central area when the height of the nozzle is different:
and (d) sequentially changing the height of the nozzle according to a set step length, and repeating the steps c to d to obtain the water quantity ratio of the edge area to the central area when the height of the nozzle is different: lambda [ alpha ]i＝2ηi/ξiWherein λ isiDenotes a nozzle height hiWater quantity ratio of edge area to center area, ηiDenotes a nozzle height hiThe ratio of the water quantity in the metering width range of the time edge region to the total water quantity of a single nozzle, xiiDenotes a nozzle height hiThe ratio of the water quantity in the metering width range right below the nozzle to the total water quantity of a single nozzle is measured;
then, calculating the water quantity ratio of the edge area to the central area when the heights of the nozzles are different and the distances between the nozzles are different:
changing the nozzle spacing in sequence according to the set step length, and repeating the steps c to e to obtain the water quantity ratio of the edge area to the central area when the nozzle heights are different and the nozzle spacing is different: lambda [ alpha ]ij＝2ηij/ξijWherein λ isijDenotes a nozzle height hiNozzle spacing of djWater quantity ratio of edge area to center area, ηijDenotes a nozzle height hiNozzle spacing of djThe ratio of the water quantity in the measuring width range of the edge region to the total water quantity of a single nozzle, xiijDenotes a nozzle height hiNozzle spacing of djThe ratio of the water quantity in the metering width range right below the nozzle to the total water quantity of a single nozzle is measured;
f. determining an optimal arrangement of nozzles
Evaluation indexes defining the nozzle arrangement manner: thetaij＝∣1-λij| and defining an optimal evaluation index: evi (i, j) ═ min { theta }ijThe obtained nozzle height h corresponding to Evi (i, j)iDistance d from nozzlejI.e. the optimal arrangement of the nozzles.
The optimal arrangement method of the flat nozzles for continuous casting comprises the following specific steps of determining the working pressure set value of the nozzles:
firstly, adopting spray detection equipment to respectively carry out pressure flow test on flat nozzles of different models to obtain a curve of the flow of each flat nozzle changing along with the pressure;
② reading the total water quantity Q of the ith cooling section from a secondary cooling water meter of a target casting steel gradeiAnd L/min, calculating the total water volume of a single nozzle in each section of the secondary cooling area:
qi＝Qi/Ni
wherein q isiThe total water quantity of a single nozzle of the ith cooling section is L/min; n is a radical ofiThe total number of the nozzles of the ith cooling section;
determining q according to the curve of flow changing with pressureiAnd taking the corresponding pressure value as the working pressure set value of the ith cooling section nozzle.
The optimized arrangement method of the flat nozzles for continuous casting comprises the following steps of: the spray coverage area was divided into several small segments and the percentage of the water distributed on each segment to the total water volume of the nozzle was recorded.
The optimal arrangement method of the flat nozzles for continuous casting changes the height of the nozzles from the initial height h to hiAfter that, hiCorresponding single nozzle spray coverage width DiCalculated by the following formula:
Di＝D·hi/h。
the optimized arrangement method of the flat nozzles for continuous casting comprises the step of arranging the interval d between two adjacent nozzlesjThe following requirements should be met:
dj≥(D′-Di)/(n-1)
d' is the spraying coverage width required in the continuous casting production process determined according to the pouring size of the target steel grade, and n is the number of the single-row nozzles of the continuous casting machine.
The optimal arrangement method of the flat nozzles for continuous casting comprises the height h of the nozzlesiThe value range is 80 mm-400 mm.
The optimized arrangement method of the flat nozzles for continuous casting comprises the step of sequentially changing the nozzle spacing according to the set step lengthjIn increments ofSequential selection of, if xii≥2ηiThen d isjTaking the minimum value.
According to the optimal arrangement method of the flat nozzles for continuous casting, in the process of testing the water distribution of the single nozzle, the water distribution of a plurality of nozzles of the same type needs to be tested, and if the fluctuation range of the spray angle is larger than 6 degrees, the nozzles of the type cannot be used.
The invention is based on the cold state performance test of the nozzle, and combines the actual continuous casting process data to determine the optimal configuration method of the nozzle under different working conditions. The method is simple and easy to implement, the obtained nozzle configuration scheme has high conformity with the actual continuous casting process, the transverse cooling uniformity of the continuous casting billet can be improved, the occurrence probability of quality defects such as cracks, bulging and the like of the continuous casting billet is reduced, and the quality of the continuous casting billet is improved.
Drawings
The present invention will be described in further detail with reference to the accompanying drawings.
FIG. 1 is a flow chart of a method for optimizing the arrangement of a flat nozzle for continuous casting according to the present invention;
FIG. 2 is a schematic diagram of the corresponding positions of the selected parameters and the selected objects in the method of the present invention;
FIG. 3 is a water distribution diagram of nozzles of the same type at the upper part of the curved section of the target continuous casting machine in the embodiment, wherein I, II and III are numbers of the nozzles of the same type;
FIG. 4 is a water distribution diagram of nozzles of the same type at the lower part of the curved section of the target continuous casting machine in the embodiment, wherein IV, V and VI are numbers of the nozzles of the same type;
FIG. 5 is a horizontal water distribution diagram of the upper part of the lower bending section in the current process of the target continuous casting machine in the embodiment;
FIG. 6 is a diagram showing the transverse water distribution of the bending section of the target continuous casting machine (numbered VII) in the prior art and optimized by the method (numbered VIII) in the embodiment.
The reference numbers in the figures are: 1. and (4) a nozzle.
The symbols in the text are: h represents the initial height of the spray nozzle, D represents the spray coverage width of a single spray nozzle, D' represents the spray overlap region width of adjacent spray nozzles, D represents the spacing between two adjacent spray nozzles, and lambda represents adjacent sprayThe ratio of water quantity in the overlapped area of nozzle spraying to the central area of the single nozzle, xi represents the ratio of water quantity in the metering width range right below the single nozzle to the total water quantity of the single nozzle, eta represents the ratio of water quantity in the metering width range of the edge area of the single nozzle spraying range to the total water quantity of the single nozzle, and lambda represents the ratio of the water quantity in the metering width range of the edge area of the single nozzle spraying rangeiDenotes a nozzle height hiWater quantity ratio of edge area to center area, ηiDenotes a nozzle height hiThe ratio of the water quantity in the metering width range of the time edge region to the total water quantity of a single nozzle, xiiDenotes a nozzle height hiThe ratio of the water quantity in the metering width range right below the nozzle to the total water quantity of a single nozzle is measured; lambda [ alpha ]ijDenotes a nozzle height hiNozzle spacing of djWater quantity ratio of edge area to center area, ηijDenotes a nozzle height hiNozzle spacing of djThe ratio of the water quantity in the measuring width range of the edge region to the total water quantity of a single nozzle, xiijDenotes a nozzle height hiNozzle spacing of djThe ratio of the water quantity in the metering width range right below the time nozzle to the total water quantity of the single nozzle, thetaijEvaluation index representing arrangement of nozzles, Evi (i, j) representing optimum evaluation index, and hiIndicating the height of the nozzle adjusted i-th time, djDenotes the nozzle spacing of the j-th adjustment, QiDenotes the total water amount of the i-th cooling stage, qiRepresents the total water quantity of a single nozzle of the ith cooling section, NiThe total number of the nozzles in the ith cooling section, D' is the spray coverage width required by the continuous casting production process determined according to the pouring size of the target steel grade, n is the number of the single-row nozzles of the continuous casting machine, theta is the spray angle of the nozzles, DiThe height of the nozzle is hiThe corresponding spraying coverage width of a single nozzle is adopted, and d' (i, j) is the height h of the nozzleiNozzle spacing of djTime adjacent nozzle spray overlap width, DgIs the diameter of the roller of the continuous casting machine.
Detailed Description
The core technology of the invention is a method for optimizing the arrangement of a flat nozzle for continuous casting, and aims to obtain the optimal selection and arrangement mode of the flat nozzle under different continuous casting working conditions by applying the method and guide the production adjustment of an actual continuous casting process, thereby improving the cooling uniformity of a continuous casting billet in a secondary cooling zone and reducing the occurrence probability of quality defects such as cracks, bulging and the like of the continuous casting billet.
The invention is based on the cold state performance test of the nozzle, and combines the actual continuous casting process data to formulate the configuration method of the nozzle under different working conditions. The method is simple and easy to implement, the obtained nozzle configuration method has high conformity with the actual continuous casting process, and can guide the production adjustment of the actual continuous casting process, improve the transverse cooling uniformity of the continuous casting billet and improve the quality of the continuous casting billet.
In order to achieve the purpose, the invention adopts the following technical scheme:
(1) calculating the total water quantity of each section of single nozzle in the secondary cooling area, q, according to the secondary cooling water meter of the target casting steel gradei＝Qi/NiWherein q isiThe total water quantity of a single nozzle of the ith cooling section is expressed in L/min; n is a radical ofiTotal number of nozzles in the i-th cooling stage, QiThe total water amount of the i-th cooling section is L/min. Adopting spray detection equipment to respectively carry out pressure flow test on different types of flat nozzles used by the continuous casting machine, and obtaining a test result and qiAnd comparing the values to obtain the actual working pressure of nozzles of different models in the continuous casting production process.
(2) And (3) taking the result in the step (1) as a working pressure set value of the nozzle, taking the arrangement height h of the nozzle of the continuous casting machine in the prior art as the initial height of the nozzle, and performing water distribution test on single nozzles of different models by adopting spraying detection equipment. And recording the spray angle theta of the nozzle, water distribution data and a spraying coverage width value D.
(3) And (4) acquiring the spraying coverage width D' required in the continuous casting production process by combining the pouring size requirement of the target steel grade. Taking the distance between two adjacent nozzles as D, wherein D is more than or equal to (D' -D)/(n-1), wherein D is the spraying coverage width of the single nozzle obtained by detection in the step (2) and is mm; n is the number of single-row nozzles of the continuous casting machine. D ' represents the width value of the spray overlapping area of the adjacent nozzles, D ' is D-D, D ' is used as the measuring width of the water quantity, the water quantity distribution data in the range of the spray covering width of the nozzles are respectively calculated according to the water quantity distribution data of the single nozzles recorded in the step (2), the ratio ξ of the water quantity in the measuring width range right below the single nozzle to the total water quantity of the single nozzle and the ratio η of the water quantity in the measuring width range of the edge area of the spray range of the single nozzle to the total water quantity of the single nozzle are calculated, and the water quantity ratio of the spray overlapping area of the adjacent nozzles to the central area of the single nozzle is calculated: λ ═ 2 η/ξ.
Changing the height of the nozzles and the spacing between the nozzles, respectively denoted hi、dj. Get Di＝D·hiH, wherein DiThe height of the nozzle is hiThe spray coverage width of the corresponding single nozzle is mm, and the spray overlap width D' (i, j) ═ D of adjacent nozzlesi-djWherein, i and j are numbers corresponding to the selected nozzle height and the spacing value respectively; mapping the water quantity distribution data in the single-nozzle spraying coverage width range (D) recorded in the step (2) to DiCalculating the height h of the nozzle by using the water distribution data after mappingiNozzle spacing of djThe ratio eta of the water quantity in the metering width range of the edge region to the total water quantity of the single nozzleijAnd a nozzle height of hiNozzle spacing of djThe ratio xi of the water quantity in the metering width range right below the time nozzle to the total water quantity of a single nozzleij。
The above formula is integrated, and the results are as follows:
dj≥(D′-D·hi/h)/(n-1) (1)
d′(i,j)＝D·hi/h-dj (2)
(4) according to the result in the step (3), the height h of the nozzle is calculatediNozzle spacing of djWater amount ratio of edge area to center area: lambda [ alpha ]ij＝2ηij/ξij. Evaluation indexes defining the nozzle arrangement manner: thetaij＝∣1-λij∣,0＜θij< 1 for characterizing the nozzle height hiNozzle spacing djThe evaluation index value corresponding to the arrangement mode of (1); defining an optimal evaluation index: evi (i, j) ═ min { theta }ijJ, i and j are respectively corresponding to the optimal nozzle height hiDistance d from nozzlej。
In the process of testing the water distribution of the nozzles, the water distribution of a plurality of nozzles of the same type needs to be detected, and the nozzles with the water distribution asymmetry difference of more than 10 percent or the spray angle fluctuation range of more than 6 degrees of a single nozzle are marked. And for the nozzle models with more marks, the frequency of using the nozzle models is reduced or the nozzle models are replaced by the nozzle with better quality meeting the requirement of the continuous casting process of the target steel grade.
The water distribution data recording method comprises the following steps: the spray coverage area was divided into several small segments and the percentage of the water distributed on each segment to the total water volume of the nozzle was recorded.
In the calculation process, hiThe value range is 80 mm-400 mm.
Nozzle spacing djSelected in increasing order, if xii≥2ηiThen d isjTaking the minimum value.
In the process of testing the cold state performance of the nozzle, the invention analyzes the symmetry of water distribution and the fluctuation value of the spray angle of the nozzle by sampling and detecting the same type of nozzle for multiple times, can screen out the nozzle with poor quality stability, reduce the use frequency of the nozzle or select the nozzle with better quality meeting the continuous casting requirement to replace the nozzle, thereby avoiding the uneven transverse cooling of the continuous casting billet caused by the quality problem of the nozzle, and fundamentally improving the cooling environment of the continuous casting secondary cooling area. Generally, nozzles having an injection angle of not more than 90 ° except for offset nozzles, have a tolerance of 0 ° to +4 °; the injection angle is larger than 90 degrees, and the tolerance is 0 degree to +6 degrees. Furthermore, the asymmetry of the water distribution of the nozzles was allowed to be 10%.
Height h of nozzleiThe value principle of (a) is hi≥0.5DgWherein D isgIs the diameter of the roller of the continuous casting machine. Research shows that on the premise of ensuring the gas-water atomization effect, the distance between the nozzle head and the surface of a casting blank cannot be less than 80mm, the height value of a commonly used nozzle is 120-200 mm, and the upper limit of the height of the nozzle is 400 mm. Based on the above, the height range of the selected nozzle in the calculation process is 80-400 mm, and the nozzle height requirements of most continuous casting machines using flat nozzles can be basically met. The water distribution of the single nozzle under the existing process is tested, so that the hair can pass the testThe method provided by the invention can be used for predicting the quality of water quantity distribution uniformity in different nozzle arrangement modes, and then selecting the optimal nozzle arrangement scheme corresponding to a certain size steel grade or a certain spraying coverage width, so that the transverse cooling uniformity of the continuous casting billet in the secondary cooling zone is improved, and the quality of the continuous casting billet is improved.
Various embodiments according to the present invention will be described in detail below with reference to the accompanying drawings.
FIG. 1 is a flow chart of the method for optimizing the arrangement of flat nozzles for continuous casting according to the present invention, which is implemented by optimizing the arrangement of nozzles in curved sections of slab casters of a certain plant, as follows:
the continuous casting machine is mainly used for producing SPHC steel grade, and the section size is 1020mm multiplied by 200 mm. Table 1 shows the corresponding casting process parameters for the bending section of the caster.
TABLE 1 continuous casting process parameters for the bending section of a continuous casting machine
Firstly, according to the water distribution amount of the cooling section in the SPHC steel continuous casting process, calculating the actual water flow rate of a single nozzle, and the actual water flow rate q of a single nozzle at the upper part and the lower part of a bending section at different drawing speeds1、q2The range of (A) is 2.3-4.0L/min, 2.5-4.0L/min. The pressure flow test is carried out on the section of nozzle, and the test result is as follows: when the test water pressure and the test air pressure are respectively 0.3MPa, the water flow of the upper nozzle of the bending section is 4.0L/min; when the test water pressure and the test air pressure are respectively 0.25MPa and 0.3MPa, the water flow of the lower nozzle of the bending section is 4.0L/min. And taking the water distribution parameter of the casting machine at the highest pulling speed as a reference, and respectively selecting 0.3MPa water pressure, 0.3MPa air pressure, 0.25MPa water pressure and 0.3MPa air pressure to respectively perform water distribution tests on the upper nozzle and the lower nozzle of the bending section.
The test results are shown in fig. 3 and 4, the water distribution of the nozzles of the same type at the upper part of the bending section is basically consistent, and the nozzles of the same type at the lower part of the bending section show larger difference. The test result shows that: the water distribution of 3 nozzles sampled and detected at the upper part of the bending section is similar, the spraying coverage width is 444mm, the spraying angle is 123.2 degrees, the water distribution asymmetry difference of the nozzles is 5 percent, and the quality of the nozzles of the model is better; the water distribution difference of 3 nozzles sampled and detected at the lower part of the bending section is larger, the spraying coverage width is 384mm, 420mm and 456mm in sequence, the corresponding spraying angles are 116.0 degrees, 120.5 degrees and 124.5 degrees, the fluctuation range of the nozzles reaches 8.5 degrees, the symmetry of No. 3 water distribution is the worst, the corresponding difference is 13.1 percent, and as can be seen from the graph 5, the transverse cooling uniformity at the lower part of the bending section of the continuous casting machine is extremely poor by applying the nozzles of the type. Considering that the water flow rate difference of the upper nozzle and the lower nozzle of the bending section is smaller under the same pressure in the actual continuous casting production process, the upper nozzle of the bending section is used for replacing the lower nozzle of the bending section.
When D' is 1020mm, h is 120mm, and D is 444mm, the formula (1) and (2) can be substituted:
dj≥510–1.85hi (3)
d′(i,j)＝3.70hi-dj (4)
according to the method provided by the invention, the theta under different nozzle arrangement modes is combined with the formulas (3) and (4)ijThe values are calculated, and the data are summarized in a table 2 (note: the selection and calculation process of the data in the table is only a simple application of the method of the invention, and a computer can also be used for realizing rapid calculation). In the embodiment, the SPHC steel is required to be sprayed in a full coverage mode, namely the minimum nozzle spacing under the height of each nozzle corresponds to the condition that the spray water quantity of the nozzles just completely covers the surface of a casting blank, and calculation is carried out once every 10mm within the nozzle height selection range; considering that the spray water amount of the nozzles completely falls on the casting blank, the minimum nozzle spacing value is taken for calculation at each nozzle height, and the calculation data is summarized as shown in table 2.
TABLE 2 Theta for different nozzle arrangementsijValue of
As can be seen from the data in Table 2, when the height of the nozzle is 80mm and 90mm, the requirement of full-coverage spraying in the continuous casting production process cannot be met; according to the height of the nozzleIncrease in value, θijThe value decreases and then increases with increasing nozzle height, theta when the nozzle height reaches 170mmijAnd 1, the width of the overlapped area of the spray of the adjacent nozzles is equal to the coverage width of the spray of the single nozzle, so that the height value of the nozzles in the range of 170-400 mm is not calculated.
Analysis of the data, θ, of Table 2ijShould be between 120-130 mm in nozzle height, within this range every 1mm apart, the calculation data is summarized as shown in table 3.
TABLE 3 Theta for different nozzle arrangementsijValue of
| Height h of nozzlei，mm | 121 | 122 | 123 | 124 | 125 | 126 | 127 | 128 | 129 |
| Minimum nozzle spacing dj，mm | 286 | 284 | 282 | 281 | 279 | 277 | 275 | 273 | 271 |
| ξiAnd 2 etaiSize and breadth | ＞ | ＞ | ＞ | ＞ | ＞ | ＞ | ＞ | ＞ | ＜ |
| θijValue of | 0.261 | 0.231 | 0.200 | 0.166 | 0.133 | 0.089 | 0.066 | 0.031 | 0.003 |
By combining the calculation results in tables 2 and 3, the evaluation method provided by the invention is adopted, the type of the nozzle Evi (i, j) is 0.003, and the corresponding nozzle arrangement mode is as follows: the height of the nozzle is 129mm, and the distance between the two nozzles is 271 mm. Therefore, the optimal arrangement of this type of nozzle in the production of SPHC steel of 1020mm 200mm size is: the height of the nozzles is 129mm, the distance between the two nozzles is 271mm, the water distribution in the arrangement mode is shown in figure 6, the distribution uniformity of the water sprayed by the nozzles in the transverse direction is obviously improved, and the improvement of the quality of a continuous casting blank is facilitated.
Compared with the prior art, the invention has the following beneficial effects:
1. the invention adopts a method of coupling the nozzle pressure flow test data with the nozzle flow in the actual production to determine the test water pressure and air pressure (no air pressure for the water nozzle), the test result has higher conformity with the working state of the nozzle in the actual production process, and by analyzing the water distribution symmetry and the spray angle fluctuation value of the flat nozzle, the nozzle with the problem and the nozzle model with poor integral quality can be found in time, the quality of the nozzle selected for continuous casting billets is ensured, and the cooling environment of the continuous casting secondary cooling zone is fundamentally improved.
2. The invention is simple and easy to implement, can be suitable for the nozzle configuration optimization of most of continuous casting machines adopting flat nozzles, and the test result can be universal for the continuous casting machines using the same or similar nozzles. In addition, the method provided by the invention can be suitable for producing continuous casting billets of different sizes, can dynamically adjust the arrangement mode of the nozzles according to the size change of the poured steel grade, and ensures that the arrangement mode of the nozzles is always in an optimal working state, thereby reducing the occurrence probability of the defects of cracks, bulging and the like of the continuous casting billets.
Claims (8)
1. An optimal arrangement method of flat nozzles for continuous casting is characterized by comprising the following steps:
a. determining a working pressure set value of the nozzle;
b. water distribution test on single nozzle
Setting the height of a nozzle of a continuous casting machine as an initial height h, setting the water inlet pressure as a working pressure set value, carrying out water distribution test on single nozzles of different models by adopting spray detection equipment, and recording the spray coverage width D of the single nozzle and water distribution data within the spray coverage width range;
c. determining the metering width of the water quantity
Calculating the width d' of the spraying overlapping area of the adjacent nozzles:
d′＝D–d
wherein d is the distance between two adjacent nozzles, and the calculated width d' of the spraying overlapping area of the adjacent nozzles is used as the metering width of the water quantity;
d. calculating the water quantity ratio lambda of the spraying overlapping area of the adjacent nozzles to the central area of the single nozzle:
according to the water distribution data in the spray coverage width range of the nozzles, calculating the ratio ξ of the water quantity in the metering width range right below the single nozzle and the total water quantity of the single nozzle, and the ratio η of the water quantity in the metering width range of the edge region of the spray coverage range of the single nozzle and the total water quantity of the single nozzle, so that the water quantity ratio of the spray overlapping region of the adjacent nozzles and the central region of the single nozzle is as follows:
λ＝2η/ξ；
e. calculating the water quantity ratio of the edge area to the central area when the heights of the nozzles are different and the distances between the nozzles are different, firstly, calculating the water quantity ratio of the edge area to the central area when the heights of the nozzles are different:
and (d) sequentially changing the height of the nozzle according to a set step length, and repeating the steps c to d to obtain the water quantity ratio of the edge area to the central area when the height of the nozzle is different: lambda [ alpha ]i＝2ηi/ξiWherein λ isiDenotes a nozzle height hiWater quantity ratio of edge area to center area, ηiDenotes a nozzle height hiThe ratio of the water quantity in the metering width range of the time edge region to the total water quantity of a single nozzle, xiiDenotes a nozzle height hiThe ratio of the water quantity in the metering width range right below the nozzle to the total water quantity of a single nozzle is measured;
then, calculating the water quantity ratio of the edge area to the central area when the heights of the nozzles are different and the distances between the nozzles are different:
changing the nozzle spacing in sequence according to the set step length, and repeating the steps c to e to obtain the water quantity ratio of the edge area to the central area when the nozzle heights are different and the nozzle spacing is different: lambda [ alpha ]ij＝2ηij/ξijWherein λ isijDenotes a nozzle height hiNozzle spacing of djWater quantity ratio of edge area to center area, ηijDenotes a nozzle height hiNozzle spacing of djThe ratio of the water quantity in the measuring width range of the edge region to the total water quantity of a single nozzle, xiijDenotes a nozzle height hiNozzle spacing of djThe ratio of the water quantity in the metering width range right below the nozzle to the total water quantity of a single nozzle is measured;
f. determining an optimal arrangement of nozzles
Evaluation indexes defining the nozzle arrangement manner: thetaij＝∣1-λij| and defining an optimal evaluation index: evi (i, j) ═ min { theta }ijThe obtained nozzle height h corresponding to Evi (i, j)iDistance d from nozzlejI.e. the optimal arrangement of the nozzles.
2. The method for optimizing the arrangement of the flat nozzles for continuous casting according to claim 1, wherein the step of determining the set value of the operating pressure of the nozzles comprises the steps of:
firstly, adopting spray detection equipment to respectively carry out pressure flow test on flat nozzles of different models to obtain a curve of the flow of each flat nozzle changing along with the pressure;
② reading the total water quantity Q of the ith cooling section from a secondary cooling water meter of a target casting steel gradeiAnd L/min, calculating the total water volume of a single nozzle in each section of the secondary cooling area:
qi＝Qi/Ni
wherein q isiThe total water quantity of a single nozzle of the ith cooling section is L/min; n is a radical ofiThe total number of the nozzles of the ith cooling section;
determining q according to the curve of flow changing with pressureiAnd taking the corresponding pressure value as the working pressure set value of the ith cooling section nozzle.
3. The method for optimizing the arrangement of flat nozzles for continuous casting according to claim 1 or 2, wherein the method for recording the water distribution data in the spray coverage width range includes: the spray coverage area was divided into several small segments and the percentage of the water distributed on each segment to the total water volume of the nozzle was recorded.
4. The method as set forth in claim 3, wherein the height of the nozzle is changed from an initial height h to hiAfter that, hiCorresponding single nozzle spray coverage width DiCalculated by the following formula:
Di＝D·hi/h。
5. the method as set forth in claim 4, wherein the distance d between two adjacent nozzles is set to be equal to or smaller than the distance d between two adjacent nozzlesjThe following requirements should be met:
dj≥(D′-Di)/(n-1)
d' is the spraying coverage width required in the continuous casting production process determined according to the pouring size of the target steel grade, and n is the number of the single-row nozzles of the continuous casting machine.
6. The method as set forth in claim 5, wherein the nozzle height h is set to be equal to or less than the nozzle height hiThe value range is 80 mm-400 mm.
7. The method as set forth in claim 6, wherein the nozzle pitch d is set as the nozzle pitch is changed in a predetermined stepjSelected in increasing order, if xii≥2ηiThen d isjTaking the minimum value.
8. The method as claimed in claim 7, wherein the water distribution test is performed on a plurality of nozzles of the same type during the water distribution test on the single nozzle, and the nozzle of the type cannot be used if the fluctuation range of the spray angle is more than 6 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011357932.3A CN112517867B (en) | 2020-11-27 | 2020-11-27 | Optimized arrangement method of flat nozzles for continuous casting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011357932.3A CN112517867B (en) | 2020-11-27 | 2020-11-27 | Optimized arrangement method of flat nozzles for continuous casting |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112517867A true CN112517867A (en) | 2021-03-19 |
| CN112517867B CN112517867B (en) | 2021-10-08 |
Family
ID=74994319
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011357932.3A Active CN112517867B (en) | 2020-11-27 | 2020-11-27 | Optimized arrangement method of flat nozzles for continuous casting |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112517867B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113340584A (en) * | 2021-08-02 | 2021-09-03 | 北京科技大学 | Method for evaluating water distribution symmetry of conical nozzle |
| CN114526932A (en) * | 2022-04-22 | 2022-05-24 | 中汽研（天津）汽车工程研究院有限公司 | Water spraying test system and method for simulating water splashing of vehicle wheel in rain |
| CN114769546A (en) * | 2022-06-17 | 2022-07-22 | 北京科技大学 | Method for improving cooling uniformity of casting blank |
| CN116511441A (en) * | 2023-07-03 | 2023-08-01 | 北京科技大学 | Nozzle optimal arrangement method based on solidification characteristics of continuous casting billets |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1191173A1 (en) * | 1984-05-11 | 1985-11-15 | Lipetskij V Pt I Litejnogo Pro | Arrangement for secondary cooling of continuously cast billet |
| JP4042541B2 (en) * | 2002-11-19 | 2008-02-06 | Ｊｆｅスチール株式会社 | Secondary cooling device and secondary cooling method for continuous cast slab |
| CN101279360A (en) * | 2008-05-15 | 2008-10-08 | 天津钢管集团股份有限公司 | Method for producing low alloyed steel continuous casting circular tube blank with a diameter of 350-400mm |
| CN202305189U (en) * | 2011-09-28 | 2012-07-04 | 中冶南方工程技术有限公司 | System for testing hot performance of continuous casting secondary cooling nozzle |
| CN103464708A (en) * | 2013-09-06 | 2013-12-25 | 上海宝锋工程技术有限公司 | Secondary cooling nozzle arranging method for silicon steel slab continuous casting |
| JP5609199B2 (en) * | 2010-03-25 | 2014-10-22 | Ｊｆｅスチール株式会社 | Secondary cooling method in continuous casting |
| CN105458206A (en) * | 2016-01-21 | 2016-04-06 | 中冶赛迪工程技术股份有限公司 | Secondary cooling method of plate billets |
| CN106825471A (en) * | 2016-12-20 | 2017-06-13 | 中冶连铸技术工程有限责任公司 | The arrangement of nozzles method and system of billet caster and slab caster |
| CN107971355A (en) * | 2017-12-07 | 2018-05-01 | 燕山大学 | A kind of spray angle optimal setting method of secondary cold-rolling unit Emulsified liquid nozzle |
| CN207479552U (en) * | 2017-10-30 | 2018-06-12 | 中冶赛迪工程技术股份有限公司 | A kind of secondary cooling water of continuous casting spraying width control device |
| CN110394436A (en) * | 2019-07-26 | 2019-11-01 | 南京钢铁股份有限公司 | A kind of secondary cooling zone spray equipment of billet caster |
| JP2020078815A (en) * | 2018-11-13 | 2020-05-28 | 日本製鉄株式会社 | Continuous casting method |
-
2020
- 2020-11-27 CN CN202011357932.3A patent/CN112517867B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1191173A1 (en) * | 1984-05-11 | 1985-11-15 | Lipetskij V Pt I Litejnogo Pro | Arrangement for secondary cooling of continuously cast billet |
| JP4042541B2 (en) * | 2002-11-19 | 2008-02-06 | Ｊｆｅスチール株式会社 | Secondary cooling device and secondary cooling method for continuous cast slab |
| CN101279360A (en) * | 2008-05-15 | 2008-10-08 | 天津钢管集团股份有限公司 | Method for producing low alloyed steel continuous casting circular tube blank with a diameter of 350-400mm |
| JP5609199B2 (en) * | 2010-03-25 | 2014-10-22 | Ｊｆｅスチール株式会社 | Secondary cooling method in continuous casting |
| CN202305189U (en) * | 2011-09-28 | 2012-07-04 | 中冶南方工程技术有限公司 | System for testing hot performance of continuous casting secondary cooling nozzle |
| CN103464708A (en) * | 2013-09-06 | 2013-12-25 | 上海宝锋工程技术有限公司 | Secondary cooling nozzle arranging method for silicon steel slab continuous casting |
| CN105458206A (en) * | 2016-01-21 | 2016-04-06 | 中冶赛迪工程技术股份有限公司 | Secondary cooling method of plate billets |
| CN106825471A (en) * | 2016-12-20 | 2017-06-13 | 中冶连铸技术工程有限责任公司 | The arrangement of nozzles method and system of billet caster and slab caster |
| CN207479552U (en) * | 2017-10-30 | 2018-06-12 | 中冶赛迪工程技术股份有限公司 | A kind of secondary cooling water of continuous casting spraying width control device |
| CN107971355A (en) * | 2017-12-07 | 2018-05-01 | 燕山大学 | A kind of spray angle optimal setting method of secondary cold-rolling unit Emulsified liquid nozzle |
| JP2020078815A (en) * | 2018-11-13 | 2020-05-28 | 日本製鉄株式会社 | Continuous casting method |
| CN110394436A (en) * | 2019-07-26 | 2019-11-01 | 南京钢铁股份有限公司 | A kind of secondary cooling zone spray equipment of billet caster |
Non-Patent Citations (2)
| Title |
|---|
| 刘青等: "喷嘴布置方式对中厚板坯连铸二次冷却效果的影响", 《北京科技大学学报》 * |
| 占贤辉: "特厚板坯连铸机二冷区喷嘴选型与布置", 《钢铁》 * |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113340584A (en) * | 2021-08-02 | 2021-09-03 | 北京科技大学 | Method for evaluating water distribution symmetry of conical nozzle |
| CN113340584B (en) * | 2021-08-02 | 2021-11-23 | 北京科技大学 | Method for evaluating water distribution symmetry of conical nozzle |
| CN114526932A (en) * | 2022-04-22 | 2022-05-24 | 中汽研（天津）汽车工程研究院有限公司 | Water spraying test system and method for simulating water splashing of vehicle wheel in rain |
| CN114526932B (en) * | 2022-04-22 | 2022-08-02 | 中汽研（天津）汽车工程研究院有限公司 | Water spraying test system and method for simulating water splashing of vehicle wheel in rain |
| CN114769546A (en) * | 2022-06-17 | 2022-07-22 | 北京科技大学 | Method for improving cooling uniformity of casting blank |
| CN116511441A (en) * | 2023-07-03 | 2023-08-01 | 北京科技大学 | Nozzle optimal arrangement method based on solidification characteristics of continuous casting billets |
| CN116511441B (en) * | 2023-07-03 | 2023-10-13 | 北京科技大学 | Nozzle optimal arrangement method based on solidification characteristics of continuous casting billets |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112517867B (en) | 2021-10-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112517867B (en) | Optimized arrangement method of flat nozzles for continuous casting | |
| CN106825479B (en) | A kind of determination method of hot delivering technology of CC billets process quenching technology for surfaces cooling water flow | |
| CN105057626B (en) | Control system and method for grain refinement of corners of continuous casting billets | |
| CN103849734B (en) | Based on quenching device flow control methods and the Detection & Controling device thereof of plate shape | |
| CN105817489B (en) | A kind of TEMPERATURE FOR HOT STRIP LAMINAR cooling technique | |
| CN111014607B (en) | Continuous casting high-quality accurate secondary cooling process | |
| CN110479776A (en) | DEVICE FOR BAR AND WIRE HOT ROLLING rolls rear closed loop control cooling system and control method | |
| CN111666653B (en) | Online judging method for setting precision of strip steel finish rolling model | |
| CN104117541A (en) | Transverse warping control method for hot-rolled martensite stainless strip steel | |
| CN110064667A (en) | A kind of steel plate laminar flow cooling means | |
| CN113426975A (en) | Efficient billet continuous casting water distribution secondary cooling research method | |
| CN105953832A (en) | Coal mill inlet primary air pipeline and air quantity and air temperature in pipeline measuring method | |
| CN206185108U (en) | Square billet secondary cooling spray set | |
| CN113083912A (en) | Hot-rolled H-shaped steel temperature uniformity control system and control method thereof | |
| CN114817830B (en) | Accurate prediction method for solidification tail end of casting blank | |
| CN108405818A (en) | A kind of equipment and technique improving micro alloyed steel sheet billet corner tissue plasticity | |
| Hu et al. | Application of a chamfered mold to improve corner defects of HSLA during slab continuous casting | |
| CN204470299U (en) | A kind of cooling device increasing high-speed bar mill on-line cooling effect | |
| CN111715708B (en) | Uniform cooling device and cooling method for wire rod after spinning and coiling | |
| CN110860565A (en) | Method for accurately realizing symmetrical shielding of strip steel edge | |
| CN106825060A (en) | The coding method of Heat Working Rolls chilling spray amount control system and spray flux record | |
| CN201375992Y (en) | Cooling device | |
| CN106370235A (en) | Specially-shaped waterway performance testing system for metallic 3D printing die | |
| CN105710131A (en) | Method for axial distribution of water yield of hot continuous rolling roller cooling water outlet | |
| CN114734014B (en) | Cooling method and system for controlling crack at corner of microalloy steel plate blank |
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 |