CN101003063A - Method for comprehensive control of elongation coefficient and plate shape of steel band during even rolling process - Google Patents

Abstract

A method for controlling the elongation percentage, plate shape, etc in the skin rolling procedure of band steel features that an elongation percentage control unit, a plate shape control unit and an integrated control unit for both elongation percentage and plate shape are used, which use respectively three different optimizing algorithms to be used in a single iterative calculation procedure consisting of multiple optimizing calculation sub-procedures.

Description

Percentage elongation, plate shape and the integrated control method of band steel in smoothing and rolling process

Technical field

The present invention relates to the cold-rolling process of steel smelting procedure, particularly percentage elongation, plate shape and the integrated control method of band steel in smoothing and rolling process.

Background technology

Fig. 1 is the schematic diagram of cold rolling levelling rolling mill practice.As shown in Figure 1, band steel 1 is delivered to planisher 3 after uncoiler 2 rolls out, through skin pass rolling, band steel 1 reaches the technological requirement of regulation and is sent to coiling machine 4 backrush, planisher carries out smooth to band steel 1, the roll of planisher comprises backing roll 5 and working roll 6, and wherein working roll directly contacts with band steel 1 surface.

For in the operation of rolling, can there be two leading indicators to weigh usually through the band rigidity behind the planisher, the one, the percentage elongation of band steel, this is a mechanical performance; Be the plate shape of band steel in addition, i.e. planarization, it is the type quality of the band steel after the processing.These two performance indications are difficult to take into account often.

For the control of planisher percentage elongation, generally be the method that adopts form to combine with operative employee's experience at present, its basic step is: (1) is according to the suitable front and back tension force of technical recipe table control selection; (2) according to the thick controlled rolling pressure of technical recipe table; (3) according to the controlling value of operative employee's experience adjustments draught pressure, make percentage elongation in the user-defined margin of tolerance.Wherein, so-called technical recipe table also is that the method that rule of thumb combines with field trial is come a given base region, and the specific aim of its specific aim steel grade is more weak.In the control of percentage elongation, do not consider plate shape factor, tend to cause strip shape quality overproof.

And in the prior art, for the control of plate shape, generally be after elongation control finishes, by the quality of range estimation (most of planisher does not have shape detection device) outlet band steel, rule of thumb the controlling value of manual setting bending roller force makes plate shape smooth good.Iff relying on the adjustment roller still to can't resolve plate shape problem, then to adjust tension force or draught pressure again and satisfy the template requirement, the percentage elongation that often do not take into account the band steel this moment causes the mechanical performance of finished product not good.

Traditional planisher that utilizes is the weak point of percentage elongation and the control of plate shape: (1) is main in the control procedure of plate shape and percentage elongation to be relied on the not strong formula table of specific aim and not to allow manageable operative employee's experience, human factor is too many, is unfavorable for the stable of product quality; (2) the control of plate shape and percentage elongation is not comprehensively considered as a whole, can not be taken into account the requirement of plate shape and mechanical performance simultaneously.

Summary of the invention

The objective of the invention is in the traditional cold roll process, exist the control of percentage elongation and plate shape thereof in formation process of band steel to rely on operative employee's experience and Artificial Control and percentage elongation that can not consideration to strip steel and the shortcoming that plate shape is carried out Comprehensive Control, be provided at percentage elongation, plate shape and the integrated control method of band steel in the smoothing and rolling process.

To achieve these goals, the present invention by the following technical solutions,

A kind of elongation controlling means of in smoothing and rolling process, being with steel, this method is carried out following steps by computer system:

(a) the relevant device parameter of collection planisher;

(b) according to the andfrictional conditions of planisher, determine coefficient of friction;

(c) band steel specification, the kind parameter of collection skin pass rolling;

(d) the main rolling technological parameter of collection planisher;

(e) call percentage elongation and draught pressure concerns counting subroutine;

(f) finish the elongation control of being with steel in the smoothing and rolling process.

A kind of board-shape control method of in smoothing and rolling process, being with steel, this method comprises the step of being carried out by computer system:

(a) the capital equipment parameter of collection planisher;

(b) characteristic parameter of collection institute rolled band steel;

(c) determine the andfrictional conditions parameter;

(d) the main rolling technological parameter of collection formation process;

(e) call plate shape and main rolling technological parameter counting subroutine;

(f) the plate shape of finishing smoothing and rolling process is calculated.

Band steel percentage elongation and plate shape integrated control method in a kind of formation process, this method comprise the following step of being carried out by computer system:

(a) collection needs the user's request parameter of the band steel of skin pass rolling;

(b) the planisher bending roller force is controlled to ground state;

(c) given total draught pressure P ₀, the total tension force T of entrance side ₀And the total tension force T of outlet side ₁Initial control parameter X ₀={ P ₀, T ₀, T ₁;

(d) call draught pressure and percentage elongation and concern that counting subroutine calculates percentage elongation ε

(e) utilize the described method of claim 8-13 to calculate the forward pull cross direction profiles σ of band steel _1i

(f) calculate corresponding belt plate shape index g ₁(X) with mechanical performance index g ₂(X);

(g) calculate corresponding plate shape and mechanical performance Comprehensive Control objective function F (X);

(h) judge whether the Powell condition is set up,, repeat above-mentioned steps d if be false) to g), set up until the Powell condition, finish to calculate, draw optimum draught pressure and tension force controlling value;

(i) calculate corresponding elongation control value according to optimum draught pressure and tension force controlling value.

In technique scheme of the present invention, percentage elongation, plate shape and the integrated control method of band steel in smoothing and rolling process are provided respectively, they are respectively to the control of the percentage elongation of band steel, the control of plate shape and plate shape and three kinds of methods of percentage elongation Comprehensive Control, diverse ways is adopted different optimization iterative calculation methods, and with them comprehensively in an iterative computation process, this process is calculated subprocess by multiple optimization and is formed, each subprocess respectively with different factors as major consideration.The present invention is on the basis of lead-in plate shape and mechanical performance Comprehensive Control object function, to mix into a unified target with type quality with the mechanical performance of steel first controls, coordination control by roll-force and front and back tension force, make the strip product after smooth can guarantee that the percentage elongation precision can satisfy the requirement of plate shape again, take into account mechanical performance and type quality index simultaneously, improved the mechanical performance and the surface quality of band steel.And control method of the present invention is simple, and control rate is fast, is suitable for online use, can enhance productivity.

Description of drawings

By below in conjunction with the description of accompanying drawing to preferred embodiment of the present invention, can further understand purpose of the present invention, feature and advantage, wherein:

Fig. 1 is the schematic diagram of skin pass rolling technology.

Fig. 2 is a skin pass rolling band steel elongation controlling means flow chart.

Fig. 3 is that percentage elongation and draught pressure concern the counting subroutine flow chart.

Fig. 4 is a band steel plastically deforming area length computation subroutine flow chart in the smoothing and rolling process.

Fig. 5 is the board-shape control method flow chart of band steel in the smoothing and rolling process.

Fig. 6 is belt plate shape and main rolling technological parameter counting subroutine flow chart.

Fig. 7 is band steel percentage elongation and a plate shape integrated control method flow chart in the smoothing and rolling process.

Fig. 8 is that planisher draught pressure and percentage elongation concern the counting subroutine flow chart

Fig. 9 is the flow chart that calculates according to the planisher elongation control of a preferred embodiment of the present invention.

Figure 10 is the flow chart that calculates according to the planisher plate shape control of a preferred embodiment of the present invention.

Figure 11 is according to percentage elongation of a preferred embodiment of the present invention and plate shape Comprehensive Control calculation flow chart.

The specific embodiment

See also shown in Figure 2, of the present invention in smoothing and rolling process the band steel elongation controlling means carry out following steps by computer system:

(a) the relevant device parameter of collection planisher;

(b) according to the andfrictional conditions of planisher, determine coefficient of friction;

(c) band steel specification, the kind parameter of collection skin pass rolling;

(d) the main rolling technological parameter of collection planisher;

(e) call percentage elongation and draught pressure concerns counting subroutine;

(f) finish the elongation control of being with steel in the smoothing and rolling process.

Reasonable is that the relevant device of planisher described in said method parameter comprises the work roll diameter d of planisher.

Reasonablely be, andfrictional conditions described in the said method comprises does smooth or wet smooth dual mode, and the former coefficientoffriction is by solid lubrication value 0.2-0.3, and latter's coefficientoffriction is according to hydrodynamic lubrication value 0.05-0.1.

Reasonable is that the band steel specification of skin pass rolling described in the said method, kind parameter comprise strip width B, thickness h, yield strength σ s, elastic modulus E, Poisson's ratio v ₁

Reasonable is that main rolling technological parameter comprises front and back tension force T described in the said method ₁, T ₀, target percentage elongation ε ₀

Reasonable is that please in conjunction with shown in Figure 3, percentage elongation described in the said method concerns that with main rolling technological parameter counting subroutine comprises the following step of being carried out by computer system:

(e1) given percentage elongation target control value ε ₀

(e2) make ε=ε ₀

(e3) call length computation subprogram in plastically deforming area in the smoothing and rolling process, obtain corresponding plastically deforming area length l;

(e4) calculate inlet asynchronous region length Δ x by following formula ₁With outlet asynchronous region length Δ x ₀:

$\mathrm{\&Delta;}{x}_0=\frac{{\mathrm{\&xi;}}_{1}l}{\sqrt{1-{\mathrm{<figure-callout\; id="1"\; label="v"\; filenames="A20061002340500191.png,A20061002340500231.png"\; state="\{\{state\}\}">v</figure-callout>}}_1\mathrm{\&psi;}}}---\left(1\right)$

$\mathrm{\&Delta;}{x}_1=\sqrt{{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A20061002340500191.png"\; state="\{\{state\}\}">l</figure-callout>}}^2+\frac{{\mathrm{\&xi;}}_0^2{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A20061002340500191.png"\; state="\{\{state\}\}">l</figure-callout>}}^2}{1-{\mathrm{<figure-callout\; id="1"\; label="v"\; filenames="A20061002340500191.png,A20061002340500231.png"\; state="\{\{state\}\}">v</figure-callout>}}_1{\mathrm{\&psi;}}_0}}-l---\left(2\right)$

In the formula: ${\mathrm{\&xi;}}_1=\sqrt{\frac{(1-v^2)({\mathrm{\&sigma;}}_s-T_0)h}{\mathrm{Eh\&epsiv;}}},$ ${\mathrm{\&xi;}}_1=\sqrt{\frac{(1-v^2)({\mathrm{\&sigma;}}_s-T_1)h(1-\mathrm{\&epsiv;})}{\mathrm{Eh\&epsiv;}}}$

ψ ₁, ψ ₀-intermediate parameters, value are 1.0-1.5

(e5) calculate elasticity of export deformed area and plastic zone intersection unit pressure p by following formula ₁, plastically deforming area average unit pressure p _m, inlet elastic deformation area and plastic zone intersection unit pressure p ₀:

${\mathrm{<figure-callout\; id="1"\; label="p"\; filenames="A20061002340500191.png,A20061002340500231.png"\; state="\{\{state\}\}">p</figure-callout>}}_1=(k_1-{\mathrm{\&sigma;}}_1)[1+\frac{2(1-v)\mathrm{\&psi;}}{v[1-\frac{2(1-2v)\mathrm{\&psi;}}{v}]}]---\left(3\right)$

$p_0=(k_0-{\mathrm{\&sigma;}}_0)[1+\frac{2(1-v){\mathrm{\&psi;}}_0}{v[1-\frac{2(1-2v)\mathrm{\&psi;}}{v}]}]---\left(4\right)$

$p_m=\frac{1}{m}(\sqrt{p_0{p}_1{e}^m}-\frac{{\mathrm{<figure-callout\; id="1"\; label="p"\; filenames="A20061002340500191.png,A20061002340500231.png"\; state="\{\{state\}\}">p</figure-callout>}}_1+p_0}{2})---\left(5\right)$

In the formula: $m=\frac{\mathrm{\&mu;l}}{h(1-\frac{2}{3}\mathrm{\&epsiv;})}$

(e6) calculate total draught pressure P by following formula ₀:

P ₀＝0.65bp ₁Δx ₀+0.5bp ₀Δx ₁+bp _ml (6)

(e7) output percentage elongation ε.

Reasonablely be, please in conjunction with shown in Figure 4, described in the said method in the smoothing and rolling process plastically deforming area length computation subprogram comprise the following step of carrying out by computer system:

(e31) given accuracy parameter δ ₀

(e32) provide the initial value l of plastic deformation section length by following formula ₀:

$l_0=\sqrt{\frac{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="A20061002340500191.png"\; state="\{\{state\}\}">R</figure-callout>}}{2}\mathrm{h\&epsiv;}}---\left(7\right)$

(e33) make l=l ₀

(e34) calculate Δ x ₁, Δ x ₀

(e35) calculate the value of corresponding intermediate variable m;

(e36) return according to the value of m and ask l;

(e37) compare l and l ₀, judge whether to satisfy $\frac{|l-l_0|}{l}\&le;{\mathrm{\&delta;}}_0$ Requirement, if satisfy then enter step (e38), otherwise adjust l ₀Initial controlling value, repeating step (e33)-(e37) is till inequality is set up;

(e38) output l.

See also shown in Figure 5,

The board-shape control method of steel of being with in smoothing and rolling process of the present invention comprises the step of being carried out by computer system:

(a) the capital equipment parameter of collection planisher;

(b) characteristic parameter of collection institute rolled band steel;

(c) determine the andfrictional conditions parameter;

(d) the main rolling technological parameter of collection formation process;

(e) call plate shape and main rolling technological parameter counting subroutine;

(f) the plate shape of finishing smoothing and rolling process is calculated.

Reasonable is that the capital equipment parameter of planisher described in the said method comprises working roll barrel length L _w, work roll diameter D _w, backing roll barrel length L _b, backing roll diameter D _b, work roll crown Δ D _WiAnd backing roll convexity Δ D _Bi, backing roll transmission side and active side housing screw centre-to-centre spacing l ₁, working roll transmission side and active side roller hydraulic cylinder centre-to-centre spacing l ₂

Reasonable is that the characteristic parameter of rolled band steel described in the said method comprises strip width B, thickness h, yield strength σ s, supplied materials thickness cross direction profiles value H _i, come flitch shape L _i

Reasonable is that andfrictional conditions described in the said method comprises does smooth or wet smooth dual mode.

Reasonable is that main rolling technological parameter comprises bending roller force S, draught pressure P, forward and backward tension force T described in the said method ₁, T ₀

Please in conjunction with shown in Figure 6, reasonable is that the shape of plate described in the said method comprises the following step of being carried out by computer system with main rolling technological parameter counting subroutine:

(e1) given accuracy parameter Δ

(e2) control band steel exports thickness distribution value h _0i

(e3) make h _i=h _0i

(e4) calculate front and back tension force cross direction profiles value σ by following equation _0i, σ _1i:

${\mathrm{\&sigma;}}_{1i}={\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="A20061002340500191.png,A20061002340500231.png"\; state="\{\{state\}\}">T</figure-callout>}}_1+\frac{E}{1-v^2}[\frac{h_i}{h(1-\mathrm{\&epsiv;})}-\frac{H_i}{h}]---\left(8\right)$

${\mathrm{\&sigma;}}_{0i}=T_0+\frac{E}{1-v^2}\{\frac{h_i}{H_i(1-\mathrm{\&epsiv;})}-1\}---\left(9\right)$

(e5) the draught pressure distribution value q ' between evaluation work roller and the band steel _i

(e6) calculate roll gap pressure distribution value q _i

(e7) calculate upper working rolls and lower working rolls vertical deflection f _Wi ^On, f _Wi ^Down

(e8) calculate exit thickness cross direction profiles h according to following formula _i:

In the formula: $K^{\&prime;}=\mathrm{\&theta;}[\mathrm{In}\frac{2d_w}{\mathrm{h\&epsiv;}+16\mathrm{\&theta;}{q}^{\&prime;}}+\frac{32\mathrm{\&theta;}{q}^{\&prime;}}{\mathrm{h\&epsiv;}+16\mathrm{\&theta;}{q}^{\&prime;}}]$

$\mathrm{\&theta;}=\frac{1-{\mathrm{<figure-callout\; id="2"\; label="v"\; filenames="A20061002340500191.png"\; state="\{\{state\}\}">v</figure-callout>}}^2}{\mathrm{\&pi;E}}$

(e9) compare h _iWith h _0i, judge whether to satisfy $\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{(h_{0i}-h_i)}^2\&le;\mathrm{\&Delta;}$ Requirement, if satisfy then enter step (e10), otherwise adjust the initial controlling value h of band steel exports thickness distribution _0i, repeating step (e2)-(e8) is till inequality is set up;

(e10) output strip forward pull cross direction profiles value σ _1i

See also shown in Figure 7,

Band steel percentage elongation and plate shape integrated control method comprise the following step of being carried out by computer system in the formation process of the present invention:

(a) collection needs the user's request parameter of the band steel of skin pass rolling;

(b) the planisher bending roller force is controlled to ground state;

(c) given total draught pressure P ₀, the total tension force T of entrance side ₀And the total tension force T of outlet side ₁Initial control parameter X ₀={ P ₀, T ₀, T ₁;

(d) call draught pressure and percentage elongation and concern that counting subroutine calculates percentage elongation ε

(e) utilize the described method of claim 8-13 to calculate the forward pull cross direction profiles σ of band steel _1i

(f) calculate corresponding belt plate shape index g ₁(X) with mechanical performance index g ₂(X);

(g) calculate corresponding plate shape and mechanical performance Comprehensive Control objective function F (X);

(h) judge whether the Powell condition is set up,, repeat above-mentioned steps d if be false) to g), set up until the Powell condition, finish to calculate, draw optimum draught pressure and tension force controlling value;

(i) calculate corresponding elongation control value according to optimum draught pressure and tension force controlling value.

Reasonablely be that the band steel user's request parameter of skin pass rolling described in the said method comprises that maximal phase that the user allows is to plate shape tolerance I ₀, maximum relative elongation tolerance Δ ε that the user allowed.

Reasonable is that please in conjunction with shown in Figure 8, draught pressure described in the said method and percentage elongation concern that counting subroutine comprises the following step of being carried out by computer system:

(d1) given computational accuracy δ;

(d2) the initial controlling value ε ' of given percentage elongation;

(d3) make ε=ε ';

(d4) call percentage elongation and draught pressure relator program in the claim 6, calculate corresponding draught pressure P ';

(d5) the total draught pressure P ' that relatively calculates and given total draught pressure P ₀, judge whether to satisfy $\frac{|P^{\&prime;}-P_0|}{P_0}\&le;\mathrm{\&delta;}$ Requirement, if satisfy then enter step (d6), otherwise adjust the initial controlling value of ε ', repeating step (d3)-(d5) is till inequality is set up;

(d6) value of the corresponding percentage elongation ε of output.

Reasonable is that the ground state bending roller force of planisher described in the said method can be represented with following formula:

$S_a=\frac{S_{\max }+S_{\min }}{2}---\left(11\right)$

In the formula: S _MaxThe maximum positive bending roller force that-planisher allowed;

S _MinThe minimal negative bending roller force that-planisher allowed, symbol is for negative

Reasonablely be the index of belt plate shape described in said method g ₁(X) with mechanical performance index g ₂(X) be respectively:

g ₁(X)＝(max(σ _1i)-min(σ _1i))/T ₁ (12)

g ₂(X)＝|ε ₀-ε|/ε ₀ (13)

Reasonable is that shape of plate described in the said method and mechanical performance Comprehensive Control objective function F (X) are defined as:

$\left\{\begin{array}{c}F\left(X\right)=\mathrm{\&alpha;}\&CenterDot;g_1\left(X\right)+(1-\mathrm{\&alpha;})\&CenterDot;g_2\left(X\right)\\ g_1\left(X\right)\&le;I_0\\ g_2\left(X\right)\&le;\mathrm{\&Delta;\&epsiv;}\end{array}\right.---\left(14\right)$

In the formula: α-weight coefficient, generally speaking α=0-1.

Below relend help preferred embodiment come the present invention is further described:

First embodiment

Can know according to rolling therory, in formation process,, and be flattened under the prerequisite that specification, steel grade and the friction condition etc. of band steel also determine, be exactly total the percentage elongation draught pressure P of band steel if roller diameter is known ₀, front and back tension force T ₁, T ₀Function, simply as the formula (15):

ε＝f ₁(P ₀，T ₁，T ₀) (15)

By the following formula finding, as long as total draught pressure P ₀, front and back tension force T ₁, T ₀Deng determining, be with the percentage elongation of steel also just to decide.Obviously, for same percentage elongation ε, total draught pressure P ₀, front and back tension force T ₁, T ₀Have the countless versions combined method to meet the demands Deng in theory, its value is not unique.In fact, smooth purpose is not only for guaranteeing that finished product satisfies mechanical performance index, also must considering the problem of plate shape.This shows that mechanical performance problems can not be only considered in the control of tension force system and draught pressure, also must consider the strip shape quality of band steel.

Fig. 9 is the flow chart that calculates according to the elongation control of a preferred embodiment of the present invention.In an embodiment of the present invention, with the control of percentage elongation as outer shroud, and with the control of plate shape as interior ring, by controlling the value of suitable total draught pressure and front and back tension force, when guaranteeing the percentage elongation index, satisfy the requirement of plate shape to greatest extent.

As shown in Figure 9, in step 1, the initial controlling value P of the at first given total draught pressure of computer system, front and back tension force ₀, T ₁, T ₀, and make X ₀={ P ₀, T ₁, T ₀.

Follow in step 2 the initial controlling value S=S of given bending roller force ₀

Then in step 3, call plate shape and main rolling technological parameter counting subroutine, calculate corresponding plate shape σ _1i

Subsequently, in step 4, computer system calculates belt plate shape index g ₁(X):

g ₁(X)＝(max(σ _1i)-min(σ _1i))/T ₁ (16)

Subsequently, in step 5,, judge whether plate shape is local best at this moment, if then explanation bending roller force controlling value this moment is best, enters step 6 by the powell condition.Otherwise the controlling value that then shows bending roller force is not the best, and plate shape still has the leeway of adjustment, therefore, changes the controlling value of bending roller force, returns step 3, till finding best bending roller force.In other words, the purpose of step (2)-step (5) be seek under current draught pressure, front and back tension force controlled condition best plate shape, i.e. local optimum plate shape.

Subsequently, in step 6, judge whether local optimum plate shape can meet consumers' demand,, otherwise adjust draught pressure, front and back tension force controlling value, return step 2, till local optimum plate shape is satisfied customer requirements if meet user's request then enter step 7.

Subsequently, in step 7, call percentage elongation and draught pressure relator program, calculate corresponding percentage elongation ε under current draught pressure and the front and back tension force controlled condition.

Subsequently, computer goes out tool performance indications g in step 8 ₂(X):

g ₂(X)＝|ε ₀-ε|/ε ₀ (17)

Subsequently, in step 9, whether mechanical performance index meets consumers' demand, if meet user's request then enter step 10, otherwise adjusts draught pressure, front and back tension force controlling value, returns step 2, till mechanical performance satisfies customer requirements.

Subsequently, in step 10, export draught pressure, front and back tension force controlling value, finish the control of percentage elongation.

Second embodiment

According to the flow of metal model in the rolling therory as can be known, the front and back tension force σ of band steel in smoothing and rolling process _1i, σ _0iAvailable formula (18) and formula (19) are represented respectively:

${\mathrm{\&sigma;}}_{1i}={\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="A20061002340500191.png,A20061002340500231.png"\; state="\{\{state\}\}">T</figure-callout>}}_1+\frac{E}{1-v^2}[\frac{h_i}{h(1-\mathrm{\&epsiv;})}-\frac{H_i}{h}]---\left(18\right)$

${\mathrm{\&sigma;}}_{0i}=T_0+\frac{E}{1-v^2}\{\frac{h_i}{H_i(1-\mathrm{\&epsiv;})}-1\}---\left(19\right)$

Equally, can know, for the exit thickness distribution value h that rolls back band steel according to the roll elastic deformation model in the plate shape theory _iCan use the function representation of formula (20):

In the formula: $K^{\&prime;}=\mathrm{\&theta;}[\mathrm{In}\frac{2d_w}{\mathrm{h\&epsiv;}+16\mathrm{\&theta;}{q}^{\&prime;}}+\frac{32\mathrm{\&theta;}{q}^{\&prime;}}{\mathrm{h\&epsiv;}+16\mathrm{\&theta;}{q}^{\&prime;}}]$

$\mathrm{\&theta;}=\frac{1-{\mathrm{<figure-callout\; id="2"\; label="v"\; filenames="A20061002340500191.png"\; state="\{\{state\}\}">v</figure-callout>}}^2}{\mathrm{\&pi;E}}$

Like this, for a specific operation of rolling, band steel supplied materials parameter such as H _i, L _i, B etc. are known, if given bending roller force S, work roll crown Δ D _WiAnd backing roll convexity Δ D _Bi, simultaneous formula (18)-(20) can be with the forward pull cross direction profiles value σ of characterization board shape _1iWith one with total draught pressure P ₀, the total tension force T of entrance side ₀And the total tension force T of outlet side ₁For the function of independent variable is represented, that is:

σ _1i＝f ₄(P ₀，T ₁，T ₀) (21)

Can know according to Field Research and theory analysis, for planisher, carry out smoothly, fully satisfy user's requirement, not only will guarantee plate shape precision, and will guarantee mechanical performance with steel with steel in order to make production.Therefore, the strip shape quality of band steel can not be only considered in the control of tension force system and draught pressure, also must consider mechanical performance problems.

Figure 10 is the flow chart that calculates according to the elongation control of a preferred embodiment of the present invention.In an embodiment of the present invention, with the control of plate shape as outer shroud, and with the control of mechanical performance as interior ring, by controlling the value of suitable total draught pressure and front and back tension force, when guaranteeing plate shape index, satisfy the requirement of mechanical performance to greatest extent.

As shown in figure 10, in step 11, the initial controlling value P of the at first given total draught pressure of computer system, front and back tension force ₀, T ₁, T ₀, and make X ₀={ P ₀, T ₁, T ₀.

Then, in step 12, call percentage elongation and draught pressure relator program, calculate corresponding percentage elongation ε under current draught pressure and the front and back tension force controlled condition.

Subsequently, computer goes out tool performance indications g in step 13 ₂(X):

g ₂(X)＝|ε ₀-ε|/ε ₀ (22)

Subsequently, in step 14, whether mechanical performance index meets consumers' demand, if meet user's request then enter step 10, otherwise adjusts draught pressure, front and back tension force controlling value, returns step 2, till mechanical performance satisfies customer requirements.

Follow in step 15 the initial controlling value S=S of given bending roller force ₀

Then in step 16, call plate shape and main rolling technological parameter counting subroutine, calculate corresponding plate shape σ _1i

Subsequently, in step 17, computer system calculates belt plate shape index g ₁(X):

g ₁(X)＝(max(σ _1i)-min(σ _1i))/T ₁ (23)

Subsequently, in step 18,, judge whether plate shape is local best at this moment, if then explanation bending roller force controlling value this moment is best, enters step 19 by the powell condition.Otherwise the controlling value that then shows bending roller force is not the best, and plate shape still has the leeway of adjustment, therefore, changes the controlling value of bending roller force, returns step 16, till finding best bending roller force.In other words, the purpose of step (15)-step (19) be seek under current draught pressure, front and back tension force controlled condition best plate shape, i.e. local optimum plate shape.

Subsequently, in step 19, judge whether local optimum plate shape can meet consumers' demand,, otherwise adjust draught pressure, front and back tension force controlling value, return step 2, till local optimum plate shape is satisfied customer requirements if meet user's request then enter step 20.

Subsequently, in step 20, export draught pressure, front and back tension force controlling value, finish the control of percentage elongation.

The 3rd embodiment

In the smooth production of reality, should take into account mechanical performance and type quality index simultaneously, and these factors also can be different for the significance level of user's request.The present invention will mix into a unified target with type quality with the mechanical performance of steel and control for this reason, and lead-in plate shape and mechanical performance are comprehensively controlled

The system object function is controlled, as the formula (24):

$\left\{\begin{array}{c}F\left(X\right)=\mathrm{\&alpha;}\&CenterDot;g_1\left(X\right)-1(1-\mathrm{\&alpha;})\&CenterDot;g_2\left(X\right)\\ g_1\left(X\right)\&le;I_0\\ g_2\left(X\right)\&le;\mathrm{\&Delta;\&epsiv;}\end{array}\right.---\left(24\right)$

In the formula:

g ₁(X)＝(max(σ _1i)-min(σ _1i))/T ₁ (25)

g ₂(X)＝|ε ₀-ε|/ε ₀ (26)

X＝{P ₀，T ₁，T ₂} (27)

I ₀The maximal phase that-user allowed is to plate shape tolerance;

The maximum relative elongation tolerance that Δ ε-user is allowed;

ε ₀-basic percentage elongation;

α-weight coefficient, according to user's different to plate shape and mechanical performance significance level, α is value between 0 to 1.

In formula (24), g ₁(X) represent plate shape index, and g ₂(X) then the steel mechanical performance index is with in representative, and obviously both are indispensable.

Figure 11 is the flow chart that calculates according to percentage elongation of a preferred embodiment of the present invention and plate shape Comprehensive Control.In an embodiment of the present invention, according to user's demand, the coordination control by roll-force and front and back tension force makes that the strip product after smooth can guarantee that the percentage elongation precision can satisfy the requirement of plate shape again, takes into account mechanical performance and type quality index simultaneously.

As shown in figure 11, in step 21,, at first bending roller force is controlled to be ground state in order to make bending roller force that bigger adjustment leeway be arranged, as the formula (28):

$S_a=\frac{S_{\max }+S_{\min }}{2}---\left(28\right)$

In the formula: S _MaxThe maximum positive bending roller force that-planisher allowed;

S _MinThe minimal negative bending roller force that-planisher allowed, symbol is for negative

Subsequently, in step 22, by the initial controlling value P of the given total draught pressure of computer system, front and back tension force ₀, T ₁, T ₀, and make X ₀={ P ₀, T ₁, T ₀.

Then, in step 23, call percentage elongation and draught pressure relator program, calculate corresponding percentage elongation ε under current draught pressure and the front and back tension force controlled condition.

Subsequently, in step 24, call plate shape and main rolling technological parameter counting subroutine, calculate the forward pull cross direction profiles σ of corresponding band steel under current draught pressure and the front and back tension force controlled condition _1i

Then, in step 25, calculate belt plate shape index g ₁(X) with mechanical performance index g ₂(X).

Subsequently, in step 26, calculate plate shape and mechanical performance Comprehensive Control objective function F (X).

Then, whether minimum by powell condition judgment plate shape and mechanical performance Comprehensive Control objective function F (X) in step 27, if then enter step 28, otherwise adjust draught pressure, front and back tension force

Controlling value is returned step 23, sets up up to the powell condition.

At last, in step 28, export draught pressure, front and back tension force controlling value, finish the control of percentage elongation.

More than by preferred embodiment the specific embodiment of the present invention has been described, but it should be understood that, here concrete description should not be construed as the qualification to the spirit and scope of the present invention, those skilled in the art make various modifications to the foregoing description after reading this specification, these all belong to scope of the present invention.

Claims (19)

1, a kind of elongation controlling means of in smoothing and rolling process, being with steel,

It is characterized in that, may further comprise the steps:

(a) the relevant device parameter of collection planisher;

(b) according to the andfrictional conditions of planisher, determine coefficient of friction;

(c) determine band steel specification, the kind parameter of skin pass rolling;

(d) the main rolling technological parameter of collection planisher;

(e) call percentage elongation and draught pressure concerns counting subroutine;

(f) control of finishing the percentage elongation in the smoothing and rolling process is calculated.

2, the elongation controlling means of band steel in the smoothing and rolling process as claimed in claim 1 is characterized in that the planisher relevant device parameter in the described step (a) comprises the work roll diameter of planisher.

3, the elongation controlling means of band steel in the smoothing and rolling process as claimed in claim 1, it is characterized in that, andfrictional conditions described in the described step (b) comprises does smooth or wet smooth dual mode, the former presses solid lubrication value 0.2-0.3 by coefficientoffriction, and latter's coefficientoffriction is according to hydrodynamic lubrication value 0.05-0.1.

4, the elongation controlling means of band steel in the smoothing and rolling process as claimed in claim 1 is characterized in that band steel specification, the kind parameter of skin pass rolling described in the described step (c) comprise strip width B, thickness h, yield strength σ s, elastic modulus E, Poisson's ratio v ₁

5, the elongation controlling means of band steel in the smoothing and rolling process as claimed in claim 1 is characterized in that, tension force T before and after main rolling technological parameter comprises described in the described step (d) ₁, T ₀, target percentage elongation ε ₀

6, the elongation controlling means of band steel in the smoothing and rolling process as claimed in claim 1 is characterized in that, percentage elongation and draught pressure described in the described step (e) concern that counting subroutine comprises the following step of being carried out by computer system:

(e1) given percentage elongation target control value ε ₀

(e2) make ε=ε ₀

(e3) call length computation subprogram in plastically deforming area in the smoothing and rolling process, obtain corresponding plastically deforming area length l;

(e4) calculate inlet asynchronous region length Δ x ₁With outlet asynchronous region length Δ x ₀

(e5) calculate elasticity of export deformed area and plastic zone intersection unit pressure p ₁, plastically deforming area average unit pressure p _m, inlet elastic deformation area and plastic zone intersection unit pressure p ₀

(e6) calculate total draught pressure P ₀

(e7) the total draught pressure controlling value P of output ₀

7, the elongation controlling means of band steel in the smoothing and rolling process as claimed in claim 6 is characterized in that, described in the described step e3 in the smoothing and rolling process plastically deforming area length computation subprogram comprise the following step of carrying out by computer system:

(e31) given accuracy parameter δ ₀

(e32) give the initial value l of plastic deformation section length ₀

(e33) make l=l ₀

(e34) calculate Δ x1, Δ x0

(e35) calculate the value of corresponding intermediate variable m;

(e36) return according to the value of m and ask l;

(e37) compare l and l ₀, judge whether to satisfy $\frac{|l-l_0|}{l}\&le;{\mathrm{\&delta;}}_0$ Requirement, if satisfy then enter step (e38), otherwise adjust l ₀Initial controlling value, repeating step (e33)-(e37) is till inequality is set up;

(e38) output l.

8, a kind of board-shape control method of being with steel in smoothing and rolling process is characterized in that, comprises the following step of being carried out by computer system:

(a) the capital equipment parameter of collection planisher;

(b) characteristic parameter of collection institute rolled band steel;

(c) determine andfrictional conditions;

(d) the main rolling technological parameter of collection formation process;

(e) call plate shape and main rolling technological parameter counting subroutine;

(f) the plate shape of finishing smoothing and rolling process is calculated.

9, the board-shape control method of being with steel in smoothing and rolling process as claimed in claim 8 is characterized in that the capital equipment parameter of planisher comprises working roll barrel length L in described (a) step _w, work roll diameter D _w, backing roll barrel length L _b, backing roll diameter D _b, work roll crown Δ D _WiAnd backing roll convexity Δ D _Bi, backing roll transmission side and active side housing screw centre-to-centre spacing l ₁, working roll transmission side and active side roller hydraulic cylinder centre-to-centre spacing l ₂

10, the board-shape control method of being with steel in smoothing and rolling process as claimed in claim 8 is characterized in that the characteristic parameter of rolled band steel comprises strip width B described in described (b) step, thickness h, yield strength σ s, supplied materials thickness cross direction profiles value H _i, come flitch shape L _i

11, the board-shape control method in smoothing and rolling process as claimed in claim 8 is characterized in that, andfrictional conditions described in described (c) step comprises does smooth or wet smooth dual mode.

12, the board-shape control method in smoothing and rolling process as claimed in claim 8 is characterized in that, main rolling technological parameter comprises bending roller force S, draught pressure P, forward and backward tension force T described in described (d) step ₁, T ₀

13, the board-shape control method in smoothing and rolling process as claimed in claim 8 is characterized in that, plate shape described in described (e) step comprises the following step of being carried out by computer system with main rolling technological parameter counting subroutine:

(e1) given accuracy parameter Δ

(e2) control band steel exports thickness distribution value h _0i

(e3) make h _i=h _0i

(e4) calculate front and back tension force cross direction profiles value σ _0i, σ _1i

(e5) the draught pressure distribution value q ' between evaluation work roller and the band steel _i

(e6) calculate roll gap pressure distribution value q _i

(e7) calculate upper working rolls and lower working rolls vertical deflection f _Wi ^On, f _Wi ^Down

(e8) calculate exit thickness cross direction profiles h _i

(e9) compare h _iWith h _0i, judge whether to satisfy $\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{(h_{0i}-h_i)}^2\&le;\mathrm{\&Delta;}$ Requirement, if satisfy then enter step (e10), otherwise adjust the initial controlling value h of band steel exports thickness distribution _0i, repeating step (e2)-(e8) is till inequality is set up;

(e10) output strip forward pull cross direction profiles value σ _1i

14, a kind of steel percentage elongation and plate shape integrated control method be with in formation process is characterized in that this method comprises the following step of being carried out by computer system:

(a) collection needs the user's request parameter of the band steel of skin pass rolling;

(b) the planisher bending roller force is controlled to ground state;

(c) given total draught pressure P ₀, the total tension force T of entrance side ₀And the total tension force T of outlet side ₁Initial control parameter X ₀={ P ₀, T ₀, T ₁;

(d) call draught pressure and percentage elongation and concern that counting subroutine calculates percentage elongation ε;

(e) calculate the forward pull cross direction profiles value σ that is with steel _1i

(f) calculate corresponding belt plate shape index g ₁(X) with mechanical performance index g ₂(X);

(g) calculate corresponding plate shape and mechanical performance Comprehensive Control objective function F (X);

(h) judge whether the Powell condition is set up,, repeat above-mentioned steps d if be false) to g), set up until the Powell condition, finish to calculate, draw optimum draught pressure and tension force controlling value;

(i) calculate corresponding elongation control value according to optimum draught pressure and tension force controlling value.

15, band steel percentage elongation and plate shape integrated control method in the formation process as claimed in claim 14 is characterized in that, the band steel user's request parameter of skin pass rolling described in described (a) step comprises that maximal phase that the user allows is to plate shape tolerance I ₀, maximum relative elongation tolerance Δ ε that the user allowed.

16, band steel percentage elongation and plate shape integrated control method in the formation process as claimed in claim 14 is characterized in that, draught pressure and percentage elongation described in described (d) step concern that counting subroutine comprises the following step of being carried out by computer system:

(d1) given computational accuracy δ;

(d2) the initial controlling value ε ' of given percentage elongation;

(d3) make ε=ε ';

(d4) call percentage elongation and draught pressure relator program in the claim 6, calculate corresponding draught pressure P ';

(d5) the total draught pressure P ' that relatively calculates and given total draught pressure P ₀, judge whether to satisfy $\frac{|P^{\&prime;}-P_0|}{P_0}\&le;\mathrm{\&delta;}$ Requirement, if satisfy then enter step (d6), otherwise adjust the initial controlling value of ε ', repeating step (d3)-(d5) is till inequality is set up;

(d6) value of the corresponding percentage elongation ε of output.

17, band steel percentage elongation and plate shape integrated control method in the formation process as claimed in claim 14 is characterized in that the ground state bending roller force of planisher can be represented with following formula in described (b) step: $S_{\mathrm{\&alpha;}}=\frac{S_{\max }+S_{\min }}{2},$ In the formula: S _MaxThe maximum positive bending roller force that-planisher allowed; S _MinThe minimal negative bending roller force that-planisher allowed.

18, planisher percentage elongation as claimed in claim 14 and plate shape Comprehensive Control Technology is characterized in that, the belt plate shape index g in described (f) step ₁(X) with mechanical performance index g ₂(X) be respectively g ₁(X)=(max (σ _1i)-min (σ _1i))/T ₁g ₂(X)=| ε ₀-ε |/ε ₀

19, band steel percentage elongation and plate shape integrated control method in the formation process as claimed in claim 14 is characterized in that plate shape and mechanical performance Comprehensive Control objective function F (X) in described (g) step are defined as:

$\left\{\begin{array}{c}F\left(X\right)=\mathrm{\&alpha;}\&CenterDot;g_1\left(X\right)+(1-\mathrm{\&alpha;})\&CenterDot;g_2\left(X\right)\\ g_1\left(X\right)\&le;I_0\\ g_2\left(X\right)\&le;\mathrm{\&Delta;\&epsiv;}\end{array}\right.$

In the formula: α-weight coefficient, generally speaking α=0-1.

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