CN110773571B - Method for controlling concentration of emulsion of secondary cold rolling unit on line - Google Patents

Method for controlling concentration of emulsion of secondary cold rolling unit on line Download PDF

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CN110773571B
CN110773571B CN201911108803.8A CN201911108803A CN110773571B CN 110773571 B CN110773571 B CN 110773571B CN 201911108803 A CN201911108803 A CN 201911108803A CN 110773571 B CN110773571 B CN 110773571B
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emulsion
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concentration
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thickness
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白振华
翟乾俊
林威
崔熙颖
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Yanshan University
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
    • B21B45/0239—Lubricating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
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Abstract

The invention provides an on-line control method for the concentration of emulsion of a secondary cold rolling unit, which belongs to the technical field of cold rolling and aims to solve the problems of the occurrence of the defects of lubricating property, rolling pressure and strip steel thickness fluctuation, strip steel thickness, strip shape and surface quality in the process of increasing and decreasing the speed of the cold rolling unit, and the method comprises the following steps: s1, collecting rolling technological parameters of the strip; s2, collecting the minimum value C of the concentration of the emulsion of the secondary cold rolling unitminAnd maximum value Cmax(ii) a S3, collecting the outlet rolling speed v1Setting a target rolling pressure value P; s4, calculating the elastic flattening radius R of the working rolly(ii) a S5, calculating the friction coefficient mu of the rolling deformation area; s6, calculating a forward slip value f of the rolling deformation area; s7, calculating the thickness xi of the oil film at the inlet of the rolling deformation zone0(ii) a S8, calculating the thickness xi of the oil film precipitated on the surface of the strip steel2(ii) a S9, establishing an online control model of the concentration of the emulsion of the secondary cold rolling unit, and calculating the corresponding concentration C of the emulsion; s10, judgment Cmin≤C≤CmaxWhether the result is true or not; and S11, regulating the concentration C of the emulsion in real time, and carrying out online real-time regulation on the concentration of the emulsion in the rolling speed-up and speed-down process.

Description

Method for controlling concentration of emulsion of secondary cold rolling unit on line
Technical Field
The invention relates to the technical field of cold rolling, in particular to an online control method for the concentration of an emulsion of a secondary cold rolling unit.
Background
The secondary cold rolling is to further reduce the thickness of the steel strip after the primary cold rolling and annealing so as to improve the hardness and strength of the material. In the production process of the secondary cold rolling unit, the strip steel is rolled and pressed down on the first rack, the thickness reduction of the strip steel is realized, the thickness requirement of a product is met, the strip steel is flattened on the second rack, the strip shape and the surface roughness of the strip steel are controlled, and the final product quality is ensured. The strip steel produced by the secondary cold rolling unit has the characteristics of thin specification and high strength, so that the first frame of the secondary cold rolling unit adopts a direct injection system to lubricate the emulsion process. In the production process of the secondary cold rolling unit, emulsion is sprayed on the surface of strip steel through a nozzle of a direct spraying system, oil drop particles in the emulsion are gradually separated out and adhered to the surface of the strip steel due to the oleophylic and hydrophobic characteristics of the surface of the strip steel, a layer of oil film is formed on the surface of the strip steel, and the oil film enters a rolling roll gap along with the strip steel for lubrication. Because the secondary cold rolling direct injection system adopts the emulsion using process with small flow and high concentration, the diameter of a through hole of an emulsion nozzle is small, the influence of flow change on injection pressure is large, and the adjustable range is narrow, so that the lubrication is not adjusted by adopting a flow optimization method.
In the production process of the secondary cold rolling unit, the concentration of the emulsion affects the rolling pressure and the fluctuation of the thickness of the strip steel, thereby affecting the rolling stability and the product quality. When the rolling speed is low, the thickness of an oil film precipitated on the surface of the strip steel by the emulsion is sufficient, the oil film introduction capacity of a rolling deformation zone is weak, the oil film on the surface of the strip steel is limited to enter the rolling deformation zone, at the moment, the oil film thickness of the rolling deformation zone is increased along with the increase of the rolling speed, the friction coefficient is reduced, and the rolling pressure is reduced. When the rolling speed is high, the oil film guiding capacity of the rolling deformation region is high, the thickness of the oil film precipitated on the surface of the strip steel is small, and the oil film is a main factor for limiting the oil film thickness of the rolling deformation region. The rolling pressure gradually decreases with the increase of the emulsion concentration, and the rolling pressure decrease gradient gradually slows down, and tends to saturate when the emulsion concentration is higher. The rolling oil content in the emulsion per unit volume is increased along with the increase of the concentration of the emulsion, so that the thickness of an oil film precipitated on the surface of the strip steel is increased, the thickness of the oil film in a rolling deformation area is increased, the friction coefficient is reduced, and the rolling pressure is reduced. Therefore, the fluctuation of the lubricating performance in the speed increasing and reducing process is compensated by controlling the concentration of the emulsion on line, the rolling pressure and the thickness fluctuation of the strip steel in the speed increasing and reducing process are effectively reduced, the thickness, the shape and the surface quality defects of the strip steel are reduced, the stable rolling and the product quality improvement in the speed increasing and reducing process of the secondary cold rolling unit are realized, and the method has further popularization and application values.
Disclosure of Invention
According to the technical problem, the method for controlling the concentration of the emulsion in the secondary cold rolling unit in an online manner is provided. The method comprehensively considers the corresponding relation among the rolling speed of the secondary cold rolling unit, the thickness of the emulsion and the thickness of the oil film precipitated on the surface of the strip steel, the thickness of the oil film in a rolling deformation region, the friction coefficient, the rolling pressure and the forward slip value, quantitatively analyzes the variation trend of the rolling pressure along with the rolling speed and the concentration of the emulsion, gives the target value of the rolling pressure of the secondary cold rolling unit, establishes a corresponding relation model between the concentration of the emulsion and the rolling speed, regulates and controls the concentration of the emulsion in the rolling speed increasing and decreasing process in an online real-time manner, provides effective technical support for the stability of the rolling pressure in the speed increasing and decreasing process of the secondary cold rolling unit, and further realizes the stable rolling of the. .
The technical means adopted by the invention are as follows:
the online control method for the concentration of the emulsion of the secondary cold rolling unit comprises the following steps:
s1, collecting rolling technological parameters of the strip;
s2, collecting the minimum value C of the concentration of the emulsion of the secondary cold rolling unitminMaximum value of emulsion concentration Cmax；
S3, collecting the outlet rolling speed v1Setting a target rolling pressure value P;
s4, calculating the elastic flattening radius R of the working rolly：
Figure BDA0002272100250000021
In the formula, R is the radius of the working roll, v is the Poisson ratio of the working roll, E is the elastic modulus of the working roll, delta h is the rolling reduction, and B is the width of the strip steel;
s5, elastically flattening the radius R according to the working roll calculated in the step S4yFurther calculating the friction coefficient mu of the rolling deformation zone:
Figure BDA0002272100250000031
wherein K is the deformation resistance of the strip steel, h0Is the inlet thickness, h1σ is the equivalent tensile stress for the exit thickness.
S6, further calculating the forward slip value f of the roll-deformed zone according to the friction coefficient μ of the roll-deformed zone calculated in the step S5:
Figure BDA0002272100250000032
in the formula, σ0For post-tensile stress, σ1Is the forward tensile stress;
s7, according to the forward slip value f of the rolling deformation zone calculated in the step S6, the thickness xi of the oil film at the entrance of the rolling deformation zone is further calculated0：
Figure BDA0002272100250000033
Wherein a is a coefficient of influence of liquid lubrication friction, B is a coefficient of influence of boundary lubrication friction, and BξIs a coefficient of friction decay index, v1Is the exit rolling speed;
s8, according to the rolling deformation zone entrance oil film thickness xi calculated in the step S70Further calculating the thickness xi of the oil film precipitated on the surface of the strip steel2：
Figure BDA0002272100250000034
Wherein α is a rolling bite angle, θ is a pressure viscosity coefficient, η0Is rolling oil dynamic viscosity;
s9, establishing an online control model of the concentration of the emulsion of the secondary cold rolling unit, and calculating the corresponding concentration C of the emulsion:
Figure BDA0002272100250000041
in the formula etaCOThe separation rate of the impact concentration of the emulsion and the strip steel is lambdawIs effective in separating out the concentration of the emulsionCoefficient of influence of rate concentration, λtIs the time influence coefficient of the concentration precipitation efficiency of the emulsion, L is the precipitation distance of the emulsion,tthe time influence coefficient of the residual efficiency of the emulsion flow,Qthe flow influence coefficient of the residual efficiency of the emulsion flow is shown, and Q is the emulsion flow;
s10, judgment Cmin≤C≤CmaxIf yes, go to step S11; if not, returning to execute the step S3;
s11, recording the rolling speed v of each group of outlets1Rolling pressure P and required emulsion concentration C, and regulating and controlling the emulsion concentration C in real time.
Further, the rolling process parameters include: rolling reduction delta h, rolling bite angle alpha, strip steel deformation resistance K and rolling oil dynamic viscosity eta0Pressure viscosity coefficient theta, strip steel width B and inlet thickness h0Outlet thickness h1Post-tensile stress sigma0Front tensile stress sigma1Emulsion flow Q, emulsion precipitation distance L, working roll radius R, working roll elastic modulus E, working roll Poisson ratio v and emulsion concentration precipitation efficiency time influence coefficient lambdatConcentration influence coefficient lambda of emulsion concentration precipitation efficiencywTime influence coefficient of residual efficiency of emulsion flowtResidual efficiency of emulsion flow and flow influence coefficientQLiquid lubrication friction influence coefficient a, boundary lubrication friction influence coefficient B and friction coefficient attenuation index Bξ。
Further, the method is applied to a secondary cold-rolled emulsion concentration online adjustment direct injection system, a static mixer is added in front of an emulsion spraying frame, rolling oil and deionized water are directly mixed into emulsion by adopting the dispersion effect of the internal structure of the static mixer, and the flow of the rolling oil conveyed by an oil pump is adjusted in real time by controlling the rotating speed of a variable frequency motor, so that the emulsion concentration is adjusted in real time online.
Compared with the prior art, the invention has the following advantages:
the online control method for the concentration of the emulsion of the secondary cold rolling mill unit can realize online control of the concentration of the emulsion of a direct injection system of the secondary cold rolling mill unit, can regulate and control the concentration of the emulsion in the rolling speed increasing and decreasing process on line in real time under the condition that the lubricating performance is ensured and the rolling pressure reaches a target value, provides effective technical guarantee for the rolling pressure in the speed increasing and decreasing process of the secondary cold rolling mill unit, effectively reduces the rolling pressure and strip steel thickness fluctuation in the speed increasing and decreasing process, and improves the rolling stability and the product quality.
For the above reasons, the present invention can be widely applied to the fields of cold rolling and the like.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to these drawings without creative efforts.
FIG. 1 is a flow chart of the method for controlling the concentration of the emulsion of the secondary cold rolling unit on line.
FIG. 2 is a schematic diagram of a secondary cold rolling mill train emulsion direct injection system.
FIG. 3 is a schematic diagram of an online concentration adjustment direct injection system for an emulsion of a secondary cold rolling mill.
Detailed Description
In order to make the technical solutions of the present invention better understood by those skilled in the art, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of the present invention.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
As shown in fig. 1, the invention provides an online control method for the concentration of an emulsion in a secondary cold rolling mill unit, as shown in fig. 2, the method is a schematic diagram of an emulsion direct injection system in the secondary cold rolling mill unit, the method is applied to the online adjustment direct injection system for the concentration of the emulsion in the secondary cold rolling mill unit as shown in fig. 3, a static mixer is added in front of an emulsion spray frame, rolling oil and deionized water are directly mixed into an emulsion by adopting the dispersion effect of the internal structure of the static mixer, and the flow of the rolling oil conveyed by an oil pump is adjusted in real time by controlling the rotating speed of a variable frequency motor, so that the online real-time adjustment of the concentration of the emulsion is realized. The specific control method is as follows:
s1, collecting the specification and steel grade of the strip, the front and back tension, the reduction rate and the emulsion flow rolling process parameters; the rolling process parameters comprise: rolling reduction delta h, rolling bite angle alpha, strip steel deformation resistance K and rolling oil dynamic viscosity eta0Pressure viscosity coefficient theta, strip steel width B and inlet thickness h0Outlet thickness h1Post-tensile stress sigma0Front tensile stress sigma1The flow Q of the emulsion, the precipitation distance L of the emulsion, the radius R of the working roll, the elastic modulus E of the working roll, the Poisson ratio v of the working roll and the time influence coefficient lambda of the precipitation efficiency of the concentration of the emulsiontConcentration influence coefficient lambda of emulsion concentration precipitation efficiencywTime influence coefficient of residual efficiency of emulsion flowtResidual efficiency of emulsion flow and flow influence coefficientQLiquid lubrication friction influence coefficient a, boundary lubrication friction influence coefficient b, friction systemNumber decay exponent Bξ。
S2, collecting the minimum value C of the concentration of the emulsion of the secondary cold rolling unitminMaximum value of emulsion concentration Cmax；
S3, collecting the outlet rolling speed v1Setting a target rolling pressure value P;
s4, calculating the elastic flattening radius R of the working rolly：
Figure BDA0002272100250000061
In the formula, R is the radius of the working roll, v is the Poisson ratio of the working roll, E is the elastic modulus of the working roll, delta h is the rolling reduction, and B is the width of the strip steel;
s5, elastically flattening the radius R according to the working roll calculated in the step S4yFurther calculating the friction coefficient mu of the rolling deformation zone:
Figure BDA0002272100250000062
wherein K is the deformation resistance of the strip steel, h0Is the inlet thickness, h1σ is the equivalent tensile stress for the exit thickness.
S6, further calculating the forward slip value f of the roll-deformed zone according to the friction coefficient μ of the roll-deformed zone calculated in the step S5:
Figure BDA0002272100250000071
in the formula, σ0For post-tensile stress, σ1Is the forward tensile stress;
s7, according to the forward slip value f of the rolling deformation zone calculated in the step S6, the thickness xi of the oil film at the entrance of the rolling deformation zone is further calculated0：
Figure BDA0002272100250000072
Wherein a is a coefficient of influence of liquid lubrication friction and b is an edgeBoundary lubrication friction coefficient of influence, BξIs a coefficient of friction decay index, v1Is the exit rolling speed;
s8, according to the rolling deformation zone entrance oil film thickness xi calculated in the step S70Further calculating the thickness xi of the oil film precipitated on the surface of the strip steel2：
Figure BDA0002272100250000073
Wherein α is a rolling bite angle, θ is a pressure viscosity coefficient, η0Is rolling oil dynamic viscosity;
s9, establishing an online control model of the concentration of the emulsion of the secondary cold rolling unit, and calculating the corresponding concentration C of the emulsion:
Figure BDA0002272100250000074
in the formula etaCOThe separation rate of the impact concentration of the emulsion and the strip steel is lambdawIs the concentration influence coefficient of the concentration of the emulsiontIs the time influence coefficient of the concentration precipitation efficiency of the emulsion, L is the precipitation distance of the emulsion,tthe time influence coefficient of the residual efficiency of the emulsion flow,Qthe flow influence coefficient of the residual efficiency of the emulsion flow is shown, and Q is the emulsion flow;
s10, judgment Cmin≤C≤CmaxIf yes, go to step S11; if not, returning to execute the step S3;
s11, recording the rolling speed v of each group of outlets1Rolling pressure P and required emulsion concentration C, and regulating and controlling the emulsion concentration C in real time.
The method for controlling the concentration of the emulsion in the secondary cold rolling unit in the invention is described in detail by taking a certain secondary cold rolling unit as an example and combining the figure 1.
Example 1
S1, collecting the specification and steel grade of the strip, the front and back tension, the reduction rate and the emulsion flow rolling process parameters; i.e. rolling with a rolling reduction Δ h of 0.050mmThe biting angle alpha is 0.012, the strip steel deformation resistance K is 390MPa, and the dynamic viscosity eta of the rolling oil00.023/Pa.s and a pressure viscosity coefficient theta of 0.012MPa-1The width B of the strip steel is 0.847m, and the inlet thickness h00.200mm, outlet thickness h10.150mm, post-tensile stress sigma0117MPa, pre-tensile stress σ1169MPa, the emulsion flow Q is 9.4L min-1The emulsion precipitation distance L is 0.5m, the working roll radius R is 162mm, the working roll elastic modulus E is 210000MPa, the working roll Poisson ratio v is 0.3, and the emulsion concentration precipitation efficiency time influence coefficient lambda ist487.6, concentration of emulsion precipitation efficiency influence system lambdaw193.5 residual efficiency time influence coefficient of emulsion flowt19.25, residual efficiency of emulsion flowQ0.494, 0.0112 of liquid lubrication friction influence coefficient a, 0.1256 of boundary lubrication friction influence coefficient B, and B of friction coefficient attenuation indexξ＝-6.582。
S2, collecting the minimum value C of the concentration of the emulsion of the secondary cold rolling unitmin1.0% and the maximum value of emulsion concentration Cmax＝15.0％；
S3, collecting the outlet rolling speed v1Setting a target rolling pressure value P according to the actual condition;
s4, calculating the elastic flattening radius R of the working rolly：
Figure BDA0002272100250000081
S5, elastically flattening the radius R according to the working roll calculated in the step S4yFurther calculating the friction coefficient mu of the rolling deformation zone:
Figure BDA0002272100250000082
s6, further calculating the forward slip value f of the roll-deformed zone according to the friction coefficient μ of the roll-deformed zone calculated in the step S5:
Figure BDA0002272100250000091
s7, according to the forward slip value f of the rolling deformation zone calculated in the step S6, the thickness xi of the oil film at the entrance of the rolling deformation zone is further calculated0：
Figure BDA0002272100250000092
S8, according to the rolling deformation zone entrance oil film thickness xi calculated in the step S70Further calculating the thickness xi of the oil film precipitated on the surface of the strip steel2：
Figure BDA0002272100250000093
S9, establishing an online control model of the concentration of the emulsion of the secondary cold rolling unit, and calculating the corresponding concentration C of the emulsion:
Figure BDA0002272100250000094
s10, judgment Cmin≤C≤CmaxIf yes, go to step S11; if not, returning to execute the step S3;
s11, recording the rolling speed v of each group of outlets1Rolling pressure P and required emulsion concentration C, and regulating and controlling the emulsion concentration C in real time.
Finally, for convenience of comparison, a typical specification TH580 strip steel product of a secondary cold rolling unit is selected as an example, the emulsion concentration online control method of the secondary cold rolling unit and the emulsion concentration and speed relation curve of the prior art are adopted, and the corresponding rolling pressure fluctuation condition is collected. As can be seen from the following table 1, after the concentration of the rolling acceleration/deceleration emulsion is regulated and controlled in real time by adopting the technology, the rolling pressure fluctuation value is reduced from 2055kN to 317kN at a certain moment, the rolling pressure fluctuation is reduced by 84.5 percent, and the rolling stability is improved. Meanwhile, the standard deviation of the fluctuation of the thickness of the strip steel is reduced from 2.75 mu m to 2.35 mu m, the standard deviation is reduced by 14.5 percent, the fluctuation of the thickness of the strip steel is reduced, and the quality of the strip steel product is improved.
TABLE 1 comparison of rolling force before and after application of the present technique and strip fluctuations in example 1
Rolling force fluctuation value (KN) Standard deviation of strip steel thickness fluctuation (mum)
Before optimization 2055 2.75
After optimization 317 2.35
Example 2
S1, collecting the specification and steel grade of the strip, the front and back tension, the reduction rate and the emulsion flow rolling process parameters; that is, the rolling reduction Δ h is 0.040mm, the rolling bite angle α is 0.012, the strip deformation resistance K is 400MPa, and the rolling oil dynamic viscosity η00.02/pas and a pressure viscosity coefficient theta of 0.01MPa-1The width B of the strip steel is 0.847m, and the inlet thickness h00.192mm, outlet thickness h10.152mm, post-tensile stress σ0115MPa, pre-tensile stress σ1157MPa, emulsion flow Q9.6 Lmin-1The emulsion precipitation distance L is 0.5m, the working roll radius R is 170mm, the working roll elastic modulus E is 210000MPa, the working roll Poisson ratio v is 0.3, and the emulsion concentration precipitation efficiency time influence coefficient lambda ist478.6, concentration of emulsion precipitation efficiency influence system lambdaw188.5, residual efficiency time influence coefficient of emulsion flowt21.26, emulsion flow residual efficiency flow influence coefficientQ0.494, 0.0112 of liquid lubrication friction influence coefficient a, 0.1256 of boundary lubrication friction influence coefficient B, and B of friction coefficient attenuation indexξ＝-6.582。
S2, collecting the minimum value C of the concentration of the emulsion of the secondary cold rolling unitmin1.0% and the maximum value of emulsion concentration Cmax＝15.0％；
S3, collecting the outlet rolling speed v1Setting a target rolling pressure value P according to the actual condition;
s4, calculating the elastic flattening radius R of the working rolly：
Figure BDA0002272100250000101
S5, elastically flattening the radius R according to the working roll calculated in the step S4yFurther calculating the friction coefficient mu of the rolling deformation zone:
Figure BDA0002272100250000111
s6, further calculating the forward slip value f of the roll-deformed zone according to the friction coefficient μ of the roll-deformed zone calculated in the step S5:
Figure BDA0002272100250000112
s7, according to the forward slip value f of the rolling deformation zone calculated in the step S6, the thickness xi of the oil film at the entrance of the rolling deformation zone is further calculated0：
Figure BDA0002272100250000113
S8, according to the rolling deformation zone entrance oil film thickness xi calculated in the step S70Further calculating the thickness xi of the oil film precipitated on the surface of the strip steel2：
Figure BDA0002272100250000114
S9, establishing an online control model of the concentration of the emulsion of the secondary cold rolling unit, and calculating the corresponding concentration C of the emulsion:
Figure BDA0002272100250000115
s10, judgment Cmin≤C≤CmaxIf yes, go to step S11; if not, returning to execute the step S3;
s11, recording the rolling speed v of each group of outlets1Rolling pressure P and required emulsion concentration C, and regulating and controlling the emulsion concentration C in real time.
Finally, for convenience of comparison, a secondary cold rolling unit of a secondary cold rolling unit 1220 in a certain steel mill is taken as an example, and long-time production data are obtained. As can be seen from the following table 2, after the concentration of the emulsifying liquid for increasing and reducing the rolling speed is regulated and controlled in real time by adopting the technology, the rolling pressure fluctuation value at a certain moment is reduced from 1986kN to 325kN, the rolling pressure fluctuation value is reduced by 83.6 percent, the rolling pressure fluctuation is reduced, and the rolling stability is improved. Meanwhile, the standard deviation of fluctuation of the strip steel thickness is reduced from 2.95 mu m to 2.45 mu m, the standard deviation is reduced by 16.9 percent, the fluctuation of the strip steel thickness is reduced, and the quality of strip steel products is improved.
TABLE 2 comparison of rolling force and strip fluctuation before and after applying the technique in example 2
Rolling force fluctuation value (KN) Standard deviation of strip steel thickness fluctuation (mum)
Before optimization 1986 2.95
After optimization 325 2.45
The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.
In the above embodiments of the present invention, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (3)

1. The online control method for the concentration of the emulsion of the secondary cold rolling unit is characterized by comprising the following steps of:
s1, collecting rolling technological parameters of the strip;
s2, collecting the minimum value C of the concentration of the emulsion of the secondary cold rolling unitminMaximum value of emulsion concentration Cmax；
S3, collecting the outlet rolling speed v1Setting a target rolling pressure value P;
s4, calculating the elastic flattening radius R of the working rolly：
Figure FDA0002615978090000011
In the formula, R is the radius of the working roll, v is the Poisson ratio of the working roll, E is the elastic modulus of the working roll, delta h is the rolling reduction, and B is the width of the strip steel;
s5, elastically flattening the radius R according to the working roll calculated in the step S4yAnd further calculating the friction coefficient mu of the rolling deformation region:
Figure FDA0002615978090000012
wherein K is the deformation resistance of the strip steel, h0Is the inlet thickness, h1Outlet thickness, σ is equivalent tensile stress;
s6, further calculating the forward slip value f of the rolled deformation zone according to the friction coefficient μ of the rolled deformation zone calculated in the step S5:
Figure FDA0002615978090000013
in the formula, σ0For post-tensile stress, σ1Is the forward tensile stress;
s7, according to the forward slip value f of the rolling deformation zone calculated in the step S6, the thickness xi of the oil film at the entrance of the rolling deformation zone is further calculated0：
Figure FDA0002615978090000021
Wherein a is a coefficient of influence of liquid lubrication friction, B is a coefficient of influence of boundary lubrication friction, and BξIs a coefficient of friction decay index, v1Is the exit rolling speed;
s8, according to the rolling deformation zone entrance oil film thickness xi calculated in the step S70Further calculating the thickness xi of the oil film precipitated on the surface of the strip steel2：
Figure FDA0002615978090000022
Wherein α is a rolling bite angle, θ is a pressure viscosity coefficient, η0Is rolling oil dynamic viscosity;
s9, establishing an online control model of the concentration of the emulsion of the secondary cold rolling unit, and calculating the corresponding concentration C of the emulsion:
Figure FDA0002615978090000023
in the formula etaCOThe separation rate of the impact concentration of the emulsion and the strip steel is lambdawIs the concentration influence coefficient of the concentration of the emulsiontIs the time influence coefficient of the concentration precipitation efficiency of the emulsion, L is the precipitation distance of the emulsion,tthe time influence coefficient of the residual efficiency of the emulsion flow,Qthe flow influence coefficient of the residual efficiency of the emulsion flow is shown, and Q is the emulsion flow;
s10, judgment Cmin≤C≤CmaxIf yes, go to step S11; if not, returning to execute the step S3;
s11, recording the rolling speed v of each group of outlets1And adjusting and controlling the concentration C of the emulsion in real time.
2. The online control method for the concentration of the emulsion of the secondary cold rolling mill set according to claim 1, wherein the rolling process parameters comprise: rolling reduction delta h, rolling bite angle alpha, strip steel deformation resistance K and rolling oil dynamic viscosity eta0Pressure viscosity coefficient theta, strip steel width B and inlet thickness h0Outlet thickness h1Post-tensile stress sigma0Front tensile stress sigma1The flow Q of the emulsion, the precipitation distance L of the emulsion, the radius R of the working roll, the elastic modulus E of the working roll, the Poisson ratio v of the working roll and the time influence coefficient lambda of the precipitation efficiency of the concentration of the emulsiontConcentration influence coefficient lambda of emulsion concentration precipitation efficiencywTime influence coefficient of residual efficiency of emulsion flowtResidual efficiency of emulsion flow and flow influence coefficientQCoefficient of influence of liquid lubrication friction a, boundaryCoefficient of influence of lubricating friction B, coefficient of friction decay index Bξ。
3. The method for controlling the concentration of the emulsion of the secondary cold rolling mill unit on line according to claim 1 or 2, wherein the method is applied to a secondary cold rolling emulsion concentration on-line regulation direct injection system, a static mixer is added in front of an emulsion spray frame, rolling oil and deionized water are directly mixed into the emulsion by adopting the dispersion effect of the internal structure of the static mixer, and the concentration of the emulsion is regulated on line in real time by controlling the rotating speed of a variable frequency motor to regulate the flow of the rolling oil delivered by an oil pump in real time.
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08132115A (en) * 1994-11-11 1996-05-28 Kawasaki Steel Corp Rolling method of steel sheet in cold rolling
CN101927261A (en) * 2010-01-02 2010-12-29 燕山大学 Method for comprehensively optimizing process lubrication system of secondary cold rolling unit in rolling mode
CN105512804A (en) * 2015-12-01 2016-04-20 燕山大学 Emulsion flow setting method taking cost integrated control as target in cold continuous rolling process
CN106391725A (en) * 2016-09-28 2017-02-15 燕山大学 Method for predicting changes of rolling pressure with change of rolling speed in cold rolling process
CN107766606A (en) * 2017-09-01 2018-03-06 燕山大学 The method for lifting secondary cold-rolling unit direct-injection system emulsion technological lubrication performance
CN108838211A (en) * 2018-06-29 2018-11-20 首钢京唐钢铁联合有限责任公司 A kind of concentration of emulsion used optimization method of cold continuous rolling process
CN107520253B (en) * 2017-09-01 2019-05-28 燕山大学 Secondary cold-rolling unit is using oil consumption control as the emulsion technique optimization method of target

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08132115A (en) * 1994-11-11 1996-05-28 Kawasaki Steel Corp Rolling method of steel sheet in cold rolling
CN101927261A (en) * 2010-01-02 2010-12-29 燕山大学 Method for comprehensively optimizing process lubrication system of secondary cold rolling unit in rolling mode
CN105512804A (en) * 2015-12-01 2016-04-20 燕山大学 Emulsion flow setting method taking cost integrated control as target in cold continuous rolling process
CN106391725A (en) * 2016-09-28 2017-02-15 燕山大学 Method for predicting changes of rolling pressure with change of rolling speed in cold rolling process
CN107766606A (en) * 2017-09-01 2018-03-06 燕山大学 The method for lifting secondary cold-rolling unit direct-injection system emulsion technological lubrication performance
CN107520253B (en) * 2017-09-01 2019-05-28 燕山大学 Secondary cold-rolling unit is using oil consumption control as the emulsion technique optimization method of target
CN108838211A (en) * 2018-06-29 2018-11-20 首钢京唐钢铁联合有限责任公司 A kind of concentration of emulsion used optimization method of cold continuous rolling process

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