CN104438354A - Method for preventing lateral bending of board in rough rolling process - Google Patents

Abstract

The invention discloses a method for preventing lateral bending of a board in the rough rolling process. According to the method for preventing lateral bending of the board in the rough rolling process, lateral bending of a rolled piece is eliminated by automatically adjusting the deviation values of roller gaps in the two sides of a rolling mill. The method for preventing lateral bending of the board in the rough rolling process comprises the following steps of A, lateral bending detection; B, calculation of a lateral bending angle and the lateral bending direction based on lateral bending detection; C, calculation of the deviation values of the roller gaps based on the lateral bending angle and the lateral bending direction of the rolled piece; D pre-setting of the deviation values of the roller gaps between passes; E, automatic adjustment of the deviation values of the roller gaps in the passes; F, self-learning of preset adjustment factors of the deviation values of the roller gaps. By the adoption of the method for preventing lateral bending of the board in the rough rolling process, lateral bending of medium and thick boards can be found in time in the multi-pass reversible rolling process of the medium and thick boards, and lateral bending of the rolled piece is eliminated by adopting a proper roller gap deviation value adjusting strategy.

Description

A kind ofly overcome the method producing lateral bending in sheet material rough rolling process

Technical field

The present invention relates to metal-pressed machine technical field, especially a kind ofly overcome the method producing lateral bending in sheet material rough rolling process.

Background technology

In prior art, in medium-thick plate and hot continuous rolling intermediate slab production process, due to the impact of unsymmetrical factors, in the operation of rolling, sheet material may produce lateral bending phenomenon, and this is one of principal element affecting product lumber recovery.Current domestic calendering factory controls also to rest in the level of Non-follow control at the longitudinal size of sheet material, operating personnel often rule of thumb and estimate the adjustment that the sheet material lateral bending degree adjustment both sides roll gap difference obtained realizes lateral bending, control effects is poor, in the operation of rolling, some unsymmetrical factors can affect the transverse gage distribution of rolled piece, make rolled piece entrance, the wedge shape rate of outlet changes, cause the generation of lateral bending, mainly contain the following aspects: along the Temperature Distribution of rolled piece width, on rolled piece width, temperature is different, the resistance of deformation of material is inevitable different, then along rolled piece width applies same draught pressure, percentage elongation is different, cause lateral bending, the stiffness difference of milling train both sides.Mill housing manufactures and in mechanical design processes, can not ensure that milling train both sides rigidity is identical, and mill drive side is connected with coupling spindle and can causes transmission side stiffness variation, so the difference of milling train both sides rigidity exists all the time.If stiffness difference is comparatively large, the draught pressure distribution on rolled piece width can be had a strong impact on, affect lateral thickness difference, center offset.Rolled piece, when nipping, due to the impact of some factor, may depart from rolling centerline, cause milling train to be subject to force unbalance, makes the thick difference in the left and right of rolled piece produce fluctuation, blank wedge shape.If initial blank exists wedge shape, cross rolling power skewness can be caused equally, cause percentage elongation different, rolling mill screwdown rate variance.The impact of rolling mill screwdown rate variance is mainly manifested in the change of both sides housing screw opening degree, from but the amount of the pressing to difference of roll both sides, this situation is mainly present in and only uses on the milling train of Electro-pressing, the impact of roll crown.If there be outer disturbing to make rolled piece to side sideslip, when using the large roll of convexity to be rolled, rolled piece transverse gage can be made to distribute and to be tending towards severe, make lateral bending trend more obvious.

Summary of the invention

The object of this invention is to provide and a kind ofly overcome the method producing lateral bending in sheet material rough rolling process.

In order to solve the problem, the technical solution used in the present invention is:

Conclude through on-the-spot actual count, the shape of lateral bending can be divided into three kinds, C type, L-type and S type, for the lateral bending of L-type and S type, on rolled piece, the curvature of relatively straight one section is also not 0, and just its absolute value is much smaller than the absolute value of curved segment.After rolled piece edge image is sent to computer, by computer, the Iamge Segmentation of rolled piece edge curve is become some sections, and simulate the function of each section of rolled piece edge curve respectively, rolled piece edge function according to current rolling pass calculates the lateral bending angle of rolled piece and lateral bending direction and judges, thus the milling train bilateral roll gap difference of lower a time is preset, and be sent to PLC system execution.In a rolling pass, according to the milling train exit rolled piece edge curve shape detected in real time, on-line amending is carried out to presetting milling train bilateral roll gap difference, is also sent to PLC system by computer and automatically performs.Meanwhile, carry out self study according to the presetting Dynamic gene of actual measurement roll gap difference to bilateral roll gap difference, to ensure that the pre-set value of roll gap difference can be good at being controlled at lateral bending angle within the deviation range allowed.

Technical scheme more specifically of the present invention can also be: carry out in six steps:

Step one: the detection of lateral bending

Install on the gap bridge high ladder of 2 industrial CCD video cameras before and after milling train, as shown in Figure 2, wherein 1 is gap bridge high ladder, and 2 is industrial CCD video camera, and 3 is milling train, and video camera is L along the surveyed area length on length of rolled piece direction _de, unit is rice.Should note when camera is installed ensureing L _debe not more than 10 meters.Send after image digitazation into computer by high speed image data acquisition card, as the object of workpiece measurement identification, computer processes digital picture, extracts marginal information, obtains the planar dimension of final rolled piece.

The field range of camera can adjust.When rolled piece through during this region according to the computer software installed, industrial CCD video camera is collected image with several adjustable sampling rate per second and is sent on the computer of IMAQ and data processing.By computer, the steps such as geometric distortion correction, noise filtering, rim detection, locations of contours, sub-pixel method edge local, planar dimension measurements and calculations are carried out to the shape image of rolled piece, the total length curve of similar strip passage as shown in Figure 3 can be obtained after treatment, wherein Y-axis is rolling centerline, workpiece front end shape approximation is processed into the straight line being parallel to roll axis, and overlap with X-axis, the unit of reference axis is millimeter.In figure tri-1 be roll, 2 for rolled piece, L _defor the length of video camera surveyed area.Concrete image detection and processing method can refer to the method in the thesis for the doctorate " research and apply of Plate Rolling Process high accuracy Side Bend Control " of He Chunyu described in chapter 6.

Step 2: the lateral bending angle detected based on lateral bending and the calculating in lateral bending direction

(1) video camera is sampled and is processed the calculating of cycle of images

When rolled piece is at the n-th passes, if n is odd number, then mean that rolled piece is from rolling after machine forward direction machine, the positive direction indication of the X-axis in this definable figure tri-is fore side, the negative direction indication of X-axis is transmission side, and Y-axis positive direction indication is after machine, and Y-axis negative direction indication is before machine.Now the image of the industrial CCD camera acquisition after machine is processed, suppose that the practical rolling speed of milling train is V _n, unit is mm/second.Record by the speed measuring coder be arranged on driving motor.Then the muzzle velocity of band is v _n, unit is mm/second:

v _n＝V _n·(1+S _n)

S _nbe the advancing slip value of rolling n-th passage, its algorithm is as follows:

$S_n={\left\{\tan \right[\frac{\mathrm{\π}}{8}\sqrt{\frac{H_n}{R}}\·\ln \left(\frac{H_n}{H_{n-1}}\right)+\frac{1}{2}\arctan \sqrt{\frac{H_{n-1}}{H_n}-1}\left]\right\}}^2$

Wherein, R is roller radius, and unit is millimeter; H _nfor the exit thickness of rolling n-th passage, unit is millimeter; H _n-1for the exit thickness of rolling (n-1)th passage, be also the inlet thickness of rolling n-th passage, unit is millimeter;

Industrial CCD video camera can be chosen along the surveyed area length L on length of rolled piece direction _de(work as L _dewhen≤5) be a curvature estimation cycle, or (work as 5<L _dewhen≤10) be a curvature estimation cycle.With L _dethe situation of≤5 is example, industrial CCD camera acquisition the cycle processing image is S (unit is second) is:

$S=\frac{L_{\mathrm{de}}}{v_n}$

This shows that the length of the rolled piece gathered each time in image does not all have lap, the adjacent image gathered is that rolled piece goes up adjacent part along its length just, only by the Images uniting of all collections in a rolling pass within a coordinate system, need can obtain the curve of rolled piece side total length.

(2) the rolled piece hop count based on image sampling and treatment cycle calculates

Make to set up data communication between the computer system of the PLC system of control milling train and sampling and processing image, to ensure when the mill speed in a passage changes, i.e. v _nwhen changing, to gather and the cycle K processing image also changes thereupon.Supposing that the rolled piece of the n-th passes exports length is L _n, the hop count that this passage rolled piece is divided into is i, then the computational methods of i are:

$i=\frac{L_n}{L_{\mathrm{de}}}$

If i is decimal, then its value is rounded up.

The subsection curve drafting of (3) n-th passage rolled pieces

The edge numerical point of the rolled piece of the n-th passes is carried out curve fitting, because rolled piece has been divided into i section, then distinguishes matching after in fact segmentation being carried out to the total length edge curve of rolled piece.That supposes one-sided edge curve on each section of rolled piece counts as m, the scope of desirable m is 10≤m≤20, then during the n-th passes, the set of the numerical point of rolled piece transmission side (analyzing for transmission side) the edge image curve that video camera first time collects after machine is: the edge numerical point set that video camera collects in milling train exit for the p time is wherein p≤i _n.I _nwhen being the n-th passes, the divided hop count of rolled piece.Because on rolled piece total length direction, width remains unchanged substantially, can assert that rolled piece fore side edge curve shape should be identical with transmission side edge curve shape.

When adopting least square method to the n-th passes, milling train outlet side video camera first time gathers and the numerical point processed carries out matching, to obtain the function of curve.Due to L _de≤ 5m, according to rolling general knowledge, within the scope of this, the edge of rolled piece may be cubic curve hardly, can not be also curve opening parabola to the left or to the right, work as L _delikely there are above two kinds of curves during > 5m.Even if there is cubic curve or opening parabola to the left and right, because its curvature is very little, also should not control accordingly for this curve, so opening upwards only need be regarded as or downward second-degree parabola curve carries out matching.If fitting function expression formula be:

Order then there is following equation group:

$\left\{\begin{array}{c}{a}_n^1{\left(x_{n1}^1\right)}^2+b_n^1{x}_{n1}^1+c_n^1=y_{n1}^1\\ a_n^1{\left(x_{n2}^1\right)}^2+b_n^1{x}_{n2}^1+c_n^1=y_{n2}^1\\ \&CenterDot;\&CenterDot;\&CenterDot;\\ a_n^1{\left(x_{\mathrm{nm}}^1\right)}^2+b_n^1{x}_{\mathrm{nm}}^1+c_n^1=y_{\mathrm{nm}}^1\end{array}\right.$

Order when error sum of squares Q reaches minimum with value be best fit approximation solution.Can be derived by the necessary condition of Function Extreme Value and draw following matrix equation:

$\left[\begin{array}{ccc}m& \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{x}_{\mathrm{nz}}^1& \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{\left(x_{\mathrm{nz}}^1\right)}^2\\ \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{x}_{\mathrm{nz}}^1& \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{\left(x_{\mathrm{nz}}^1\right)}^2& \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{\left(x_{\mathrm{nz}}^1\right)}^3\\ \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{\left(x_{\mathrm{nz}}^1\right)}^2& \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{\left(x_{\mathrm{nz}}^1\right)}^3& \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{\left(x_{\mathrm{nz}}^1\right)}^4\end{array}\right]\left[\begin{array}{c}{c}_n^1\\ b_n^1\\ a_n^1\end{array}\right]=\left[\begin{array}{c}\underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{y}_{\mathrm{nz}}^1\\ \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{x}_{\mathrm{nz}}^1\&CenterDot;y_{\mathrm{nz}}^1\\ \underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{\left(x_{\mathrm{nz}}^1\right)}^2\&CenterDot;y_{\mathrm{nz}}^1\end{array}\right](z\&le;m)$

Due to with known, this is a system of linear equations with three unknown numbers, three equations, the unknown number in solving equation group with its best fit approximation solution can be obtained.In like manner, can try to achieve best fit approximation solution.So far, the conic section function of all m sections after the n-th passes can be obtained.Rolled piece is in the n-th passage, and the edge curvilinear function domain of definition of the p time sampling section is $(x_{n1}^p,x_{\mathrm{nm}}^p).$

(4) rolled piece edge curve and rolling centerline angle (i.e. lateral bending angle) calculate

On rolled piece each section successively by milling train and through video camera sampling process as shown in the figure, wherein dash area represents the region that current camera is being sampled, and the positive direction of Y-axis is rolling direction.Fig. 4 represents the process of video camera first time sampling on rolled piece, Fig. 5 represents the process of video camera second time sampling on rolled piece, Fig. 6 represents the process of video camera third time sampling on rolled piece, Fig. 7 represents the process of video camera the 4th sampling on rolled piece, the rest may be inferred, until terminate i-th sampling of rolled piece.Gather angle between image edge conic section and rolling centerline to the n-th passage first time below to calculate, as shown in the figure, six kinds of situations are divided to consider, wherein Fig. 8 and Fig. 9 may be certain part away from milling train one end on rolled piece after the n-th passes, Fig. 8 to represent on rolled piece away from certain part of milling train one end to fore side deflection, be considered as situation 1, Fig. 9 and represent that rolled piece makes lateral deviation away from certain part of milling train one end to transmission is oblique, be considered as situation 2; Figure 10 and Figure 11 may be certain part near milling train one end on rolled piece, Figure 10 represents that certain part of close milling train one end on rolled piece is to fore side deflection, be considered as situation 3, Figure 11 and represent that the part of close milling train one end on rolled piece makes lateral deviation tiltedly to transmission, be considered as situation 4; Figure 12, Figure 13 and Figure 14 may be any part on rolled piece, Figure 12 represents that on rolled piece, certain part is to fore side slight deflection, Figure 13 represents that on rolled piece, certain part is to transmission side slight deflection, and Figure 14 represents that certain part on rolled piece is straight for being close to, and Figure 12, Figure 13 and Figure 14 are unified is considered as situation 5.Based on analysis above, when occurring situation 5 and situation 6, because the radius of curvature of its curve is very little, therefore still according to opening upwards or under parabolic curve carry out matching.Still choose rolled piece transmission side edge curve to analyze.

Below the angle that the rolled piece transmission side edge curve of the n-th passage first time sampling and the parallel lines of rolling centerline intersect at each numerical point place is calculated.

Can obtain quadratic function differentiate:

Will substitution above formula can obtain curve and exist place's tangent slope is:

Then the angle (i.e. lateral bending angle) of this tangent line and rolling centerline is:

$\left\{\begin{array}{c}{\mathrm{\&alpha;}}_{n1}^1=90-\arctan (2{\mathrm{ax}}_{n1}^1+b),\arctan (2a{x}_{n1}^1+b)\&GreaterEqual;0\\ {\mathrm{\&alpha;}}_{n1}^1=-[90+\arctan (2a{x}_{n1}^1+b)],\arctan (2a{x}_{n1}^1+b)<0\end{array}\right.$

In like manner can obtain the angle at other each numerical point places the then angle mean value of the n-th passage first time sampled point for:

$\stackrel{\&OverBar;}{{\mathrm{\&alpha;}}_n^1}=\frac{\underset{z=1}{\overset{m}{\mathrm{\&Sigma;}}}{\mathrm{\&alpha;}}_{\mathrm{nz}}^1}{m}$

referred to as the lateral bending angle of rolled piece part in image during the n-th passage first time sampling.The lateral bending angle of other each passages calculates the same, repeats no more.Then the lateral bending angle set of the n-th passage rolled piece is

(5) determination methods in rolled piece lateral bending direction

Conic section function after matching is symmetry axis is following 6 kinds of situations are divided into judge:

If a. judge in all numerical points be all less than and when time parabola Open Side Down, illustrate that the lateral bending direction of rolled piece is fore side, belong to situation 1.

If b. judge in all numerical points be all greater than and when time parabola Open Side Down, illustrate that the lateral bending direction of rolled piece is transmission side, belong to situation 2.

If c. judge in all numerical points be all less than and when time parabola opening upwards, illustrate that the lateral bending direction of rolled piece is fore side, belong to situation 3.

If d. judge in all numerical points be all greater than and when time parabola opening upwards, illustrate that the lateral bending direction of rolled piece is transmission side, belong to situation 4.

E. when time, unification is considered as situation 5.

If f. judge middle component values point is less than component values point is greater than then illustrate that the lateral bending degree of this part on rolled piece is excessive, cannot be controlled by adjustment roll gap difference, can only consider to excise this part.

Step 3: based on the roll gap mathematic interpolation in rolled piece lateral bending angle and lateral bending direction

Suppose that Δ s is that milling train bilateral roll gap is poor, unit is millimeter, and its computational methods are:

Δs＝s _ds-s _os

Wherein s _dsfor transmission side roll gap, s _osfor fore side roll gap, unit is millimeter.

When supposing to detect that lateral bending phenomenon appears in a time rolled piece, as-2 ° of < α < 2 °, roll gap difference does not make any adjustments, and is Δ s=Δ s ⁱ+ t=Δ s ⁱ+ 0=Δ s ⁱ; As 2 °≤α < 15 ° or-15 °≤α <-2 °, setting roll gap difference Δ s=Δ s ⁱ+ t=Δ s ⁱ+ 0.1f; As 15 °≤α < 25 ° or-25 °≤α <-15 °, setting roll gap difference Δ s=Δ s ⁱ+ 0.25f; As 25 °≤α < 35 ° or-35 °≤α <-25 °, setting roll gap difference Δ s=Δ s ⁱ+ 0.5f; As 35 °≤α < 45 ° or-45 °≤α <-35 °, setting roll gap difference Δ s=Δ s ⁱ+ 0.8f; When 45 °≤α or α≤-45 °, should consider to excise leg portion, and the method provided in this patent can not be provided.Wherein f is roll gap difference Dynamic gene, and its span is-2≤f≤2, and initial value is ± 1, and when lateral bending direction is transmission side, initial value is taken as-1, and when lateral bending direction is fore side, initial value is taken as 1; T is roll gap difference adjustment amount, and unit is millimeter.When rolled piece lateral bending being detected first, Δ s ⁱfor the original roll gap difference of mill personnel after carrying out mill roll-gap leveling, unit is millimeter, ideally Δ s ₀=0; When non-rolled piece lateral bending detected first time, Δ s ⁱfor the actual roll gap deviate at the end of upper a time rolling.

The size of f value is determined by the lateral bending angle of rolled piece, and lateral bending angle is larger, then the absolute value of f is larger.The symbol of f value is determined by the lateral bending direction of rolled piece, when lateral bending direction is fore side, f be on the occasion of, lateral bending direction is transmission side, and f is negative value.

Step 4: presetting between the passage of roll gap difference

According to the testing result of upper a time rolled piece lateral bending degree, i.e. the combination collocation situation of situation 1-6 and the numerical value at lateral bending angle, judge that this lateral bending belongs to the lateral bending of which type and the degree of lateral bending, and the bilateral roll gap difference of lower a time is set.To i sampled all in the n-th rolling pass _nsection rolled piece edge curve carries out lateral bending walking direction, according to sampling order successively, then occurs that following situation is judged as C type lateral bending when combining:

(1) situation 1 → situation 5 → situation 3

(2) situation 2 → situation 5 → situation 4

Occur that following situation is judged as L-type lateral bending when combining:

(3) situation 5 → situation 3

(4) situation 5 → situation 4

(5) situation 1 → situation 5

(6) situation 2 → situation 5

Occur that following situation is judged as S type lateral bending when combining:

(7) situation 1 → situation 5 → situation 4

(8) situation 2 → situation 5 → situation 3

After n-th rolling terminates, if be judged as C type lateral bending, then the roll gap difference in the (n+1)th rolling pass can be set as steady state value, namely wherein it is the n-th passage i-th _nthe actual roll gap difference of section, known with can obtain with then $t_{n+1}=\frac{1}{2}(t_n^1+t_n^{i_n}).$ Δ s _n+1.

After n-th rolling terminates, if be judged as L-type or S type lateral bending, then the roll gap difference in the (n+1)th rolling pass is changing value.When being judged as L-type lateral bending, the section being only not less than 2 ° at lateral bending angle carries out the adjustment of roll gap difference, and other sections being less than 2 ° still return to the roll gap difference at the end of the n-th passage.When being judged as S type lateral bending, the outlet length of the (n+1)th rolling pass rolled piece is divided into two sections, the last period regulates direction just in time contrary with the roll gap difference of latter a section, i.e. t _n+1numerical value become negative from positive number, or become positive number from negative.Its size is determined by lateral bending angle.

Suppose that the length that the (n+1)th passage rolls rear rolled piece is L _n+1, unit is millimeter.This value can be determined according to constant-volume principle in the rolled piece operation of rolling, and this does not repeat.In the (n+1)th passes process, the length that roll surface turns over is L _{r (n+1)}, unit is millimeter:

$L_{r(n+1)}=\frac{L_{n+1}}{1+S_{n+1}}+\sqrt{\mathrm{\&Delta;}{h}_{n+1}\&times;R}$

Wherein S _n+1it is the advancing slip value of the (n+1)th passage; Δ h _n+1be the drafts of the (n+1)th passage, unit is millimeter; R is the radius of roll, and unit is millimeter.

When being judged as L-type lateral bending, suppose the z near mill portion on the n-th passage outlet rolled piece _n+1section lateral bending angle is all not less than 2 °, and remainder lateral bending angle is all less than 2 °.Then as rolled piece timing P from nipping _n+1after second, bilateral roll gap deviate returns to the roll gap difference at the end of the n-th passage.P _n+1unit is second, and its computational methods are:

$P_{n+1}=\frac{L_{r(n+1)}/i_{n+1}}{V_{n+1}}\&CenterDot;z_{n+1}$

Suppose the z away from mill portion on the n-th passage outlet rolled piece _n+1section lateral bending angle is all not less than 2 °, and remainder lateral bending angle is all less than 2 °.Then as rolled piece timing P from nipping _n+1after second, bilateral roll gap deviate is adjusted to the pre-set value of the n-th passage by the roll gap difference at the end of the n-th passage.P _n+1unit is second, and its computational methods are:

$P_{n+1}=\frac{L_{r(n+1)}/i_{n+1}}{V_{n+1}}\&CenterDot;(i_{n+1}-z_{n+1})$

When being judged as S type lateral bending, suppose that the rolled piece muzzle velocity of the (n+1)th passage is v _n+1, unit is mm/second; The linear velocity of roll is V _n+1, unit is mm/second.Then as rolled piece timing P from nipping _n+1after second, the adjustment direction of bilateral roll gap deviate changes, i.e. t _n+1numerical value start to become negative from positive number, or become positive number from negative.P _n+1unit is second, and its computational methods are:

$P_{n+1}=\frac{L_{r(n+1)}/2}{V_{n+1}}$

Step 5: self-adjusting in the passage of roll gap difference

In a passage during rolling, according to the real time feedback image of milling train exit camera, on basis presetting between passage, carry out the self adaptation fine setting of bilateral roll gap difference.Presetting roll gap difference is in the actual operation of rolling, occur sometimes roll gap tilt quantity cannot eliminate within lateral bending to allowed band not or the excessive rolled piece that causes that tilts to the situation of another direction lateral bending, the fine setting of roll gap difference self adaptation therefore in passage just seems and is even more important.Suppose that the adaptive trim values of the n-th passage roll gap difference is rolling passage need adjust i _nsecondary.When detecting that rolled piece lateral bending direction is fore side, Δ t _nfor on the occasion of, lateral bending direction is transmission side, Δ t _nfor negative value.This value is superimposed upon in presetting roll gap difference, supposes that the actual roll gap deviate after superposing is Δ s ' _n, unit is millimeter.Δ t _ncomputational methods as follows:

As-2 ° of < α < 2 °, roll gap difference does not make any adjustments, and is Δ t=0, without the need to intervening roll gap difference; As 2 °≤α < 15 ° or-15 °≤α <-2 °, roll gap difference adaptation value Δ t=0.005g millimeter; As 15 °≤α < 25 ° or-25 °≤α <-15 °, roll gap difference adaptation value Δ t=0.01g millimeter; As 25 °≤α < 35 ° or-35 °≤α <-25 °, roll gap difference adaptation value Δ t=0.015g millimeter; As 35 °≤α < 45 ° or-45 °≤α <-35 °, roll gap difference adaptation value Δ t=0.02g millimeter; When 45 °≤α or α≤-45 °, should consider to excise leg portion, and the method provided in this patent can not be provided.Wherein, g is Adaptive Adjustment of Step Length ,-10≤g≤10, when detecting that rolled piece lateral bending direction is fore side, g be on the occasion of; When lateral bending direction is transmission side, g is negative value.

Step 6: the self study of the presetting Dynamic gene f of roll gap difference

Consider adopt exponential smoothing to the n-th passage the presetting Dynamic gene f of roll gap difference carry out self study.By the actual roll gap deviate Δ s ' after self adaptation _ncarry out inverse, presetting Dynamic gene can be obtained absolute value be:

Wherein for carrying out inverse by actual roll gap deviation, lateral bending angle interval [2 °, 15 °) or [-15 ° ,-2 °) interior time presetting Dynamic gene; for carrying out inverse by actual roll gap deviation, lateral bending angle interval [15 °, 25 °) or [-25 ° ,-15 °) in time presetting Dynamic gene; for carrying out inverse by actual roll gap deviation, lateral bending angle interval [25 °, 35 °) or [-35 ° ,-25 °) in time presetting Dynamic gene; for carrying out inverse by actual roll gap deviation, lateral bending angle interval [35 °, 45 °) or [-45 ° ,-35 °) in time presetting Dynamic gene.

The then presetting Dynamic gene f of the (n+1)th passage _n+1absolute value be:

Wherein, if all non-self study of the presetting Dynamic gene of front n passage, then f _na, f _nb, f _nc, f _ndinitial value be ± 1, still should judge that it is plus or minus according to the lateral bending direction of rolled piece; β is gain coefficient, 0≤β≤1; f _{(n+1) a}for lateral bending angle interval [2 °, 15 °) or [-15 ° ,-2 °) interior time presetting Dynamic gene; for lateral bending angle interval [15 °, 25 °) or [-25 ° ,-15 °) interior time presetting Dynamic gene; for lateral bending angle interval [25 °, 35 °) or [-35 ° ,-25 °) in time presetting Dynamic gene; for lateral bending angle interval [35 °, 45 °) or [-45 ° ,-35 °) in time presetting Dynamic gene.When the lateral bending angle numerical value of certain section of edge curve on rolled piece falls into [2 °, interval, 15 °), [15 °, 25 °), [25 °, 35 °), [35 °, 45 °), [-15 ° ,-2 °), [-25 °,-15 °), [-35 °,-25 °), [-45 ° ,-35 °) time, then according to upper two formulas respectively to f _nnumerical value carry out self study and upgrade, if judge lateral bending angle not in above each interval, then f _nnumerical value does not carry out self study.

Accompanying drawing explanation

Fig. 1 a kind ofly overcomes the method flow diagram producing lateral bending in sheet material rough rolling process;

Fig. 2 is industrial CCD camera installation locations schematic diagram;

Fig. 3 is rolled piece boundary curve rectangular coordinate system schematic diagram;

Fig. 4-Fig. 7 is first to fourth sample area example schematic in the operation of rolling;

The example schematic that when Fig. 8 is situation 1, rolled piece edge curve is crossing with the parallel lines of rolling centerline.

The schematic diagram of certain partial shape on rolled piece when Fig. 9 is situation 2.

The schematic diagram of certain partial shape on rolled piece when Figure 10 is situation 3.

The schematic diagram of certain partial shape on rolled piece when Figure 11 is situation 4.

The schematic diagram of certain part three kinds of shapes on rolled piece when Figure 12-Figure 14 is situation 5.

Detailed description of the invention one

Step one: the detection of lateral bending

Install on the gap bridge high ladder of 2 industrial CCD video cameras before and after milling train, as shown in Figure 2, wherein 1 is gap bridge high ladder, and 2 is industrial CCD video camera, and 3 is milling train, and video camera is L along the surveyed area length on length of rolled piece direction _de, unit is rice.Should note when camera is installed ensureing L _debe not more than 10 meters.Send after image digitazation into computer by high speed image data acquisition card, as the object of workpiece measurement identification, computer processes digital picture, extracts marginal information, obtains the planar dimension of final rolled piece.

The field range of camera can adjust.When rolled piece through during this region according to the computer software installed, industrial CCD video camera is collected image with several adjustable sampling rate per second and is sent on the computer of IMAQ and data processing.By computer, the steps such as geometric distortion correction, noise filtering, rim detection, locations of contours, sub-pixel method edge local, planar dimension measurements and calculations are carried out to the shape image of rolled piece, the total length curve of similar strip passage as shown in Figure 3 can be obtained after treatment, wherein Y-axis is rolling centerline, workpiece front end shape approximation is processed into the straight line being parallel to roll axis, and overlap with X-axis, the unit of reference axis is millimeter.In Fig. 31 be roll, 2 for rolled piece, L _defor the length of video camera surveyed area.Concrete image detection and processing method can refer to the method in the thesis for the doctorate " research and apply of Plate Rolling Process high accuracy Side Bend Control " of He Chunyu described in chapter 6.

Step 2: the lateral bending angle detected based on lateral bending and the calculating in lateral bending direction

Consider the lateral bending defect being eliminated rolled piece by adjustment milling train bilateral roll gap deviate.

(1) video camera is sampled and is processed the calculating of cycle of images

Calculate for the situation of rolled piece when the 9th passes, suppose the rolled piece lateral bending situation detecting front 8 passages, the absolute value at its lateral bending angle is all less than 2 °, because the bilateral roll gap difference of 8 passages is before this constant all the time.The positive direction indication of the X-axis in this definable Fig. 3 is fore side, and the negative direction indication of X-axis is transmission side, and Y-axis positive direction indication is after machine, and Y-axis negative direction indication is before machine.Now the image of the industrial CCD camera acquisition after machine is processed, suppose that the roll line speed feedback value of milling train is 1500mm/s, record by the speed measuring coder be arranged on driving motor.Wherein, R is roller radius, R=500 millimeter; H ₉for the exit thickness of rolling the 9th passage, H ₉=17.5 millimeters; H ₈for the exit thickness of rolling the 8th passage, H ₈=13.89 millimeters.

Suppose S ₉be the advancing slip value of rolling the 9th passage, its algorithm is as follows:

$S_n={\left\{\tan \right[\frac{\mathrm{\&pi;}}{8}\sqrt{\frac{13.89}{500}}\&CenterDot;\ln \left(\frac{13.89}{17.5}\right)+\frac{1}{2}\arctan \sqrt{\frac{17.5}{13.89}-1}\left]\right\}}^2=0.0577$

Then the muzzle velocity of band is v _n:

v _n＝1500·(1+0.0577)＝1586.55mm/s

Industrial CCD video camera can be chosen along the surveyed area length L on length of rolled piece direction _de=5000mm.Industrial CCD camera acquisition the cycle processing image is S (unit is second) is:

$S=\frac{5000}{1586.55}=3.15s$

This shows that the length of the rolled piece gathered each time in image does not all have lap, the adjacent image gathered is that rolled piece goes up adjacent part along its length just, only by the Images uniting of all collections in a rolling pass within a coordinate system, need can obtain the curve of rolled piece side total length.

(2) the rolled piece hop count based on image sampling and treatment cycle calculates

Make to set up data communication between the computer system of the PLC system of control milling train and sampling and processing image, to ensure when the mill speed in a passage changes, i.e. v _nwhen changing, to gather and the cycle K processing image also changes thereupon.Supposing that the rolled piece of the 9th passes exports length is L ₉=25000mm, the hop count that this passage rolled piece is divided into is i, then the computational methods of i are:

$i=\frac{25000}{5000}=5$

The segmentation of (3) the 9th passage rolled pieces

The edge numerical point of the rolled piece of the 9th passes is carried out curve fitting, because rolled piece has been divided into 5 sections, then distinguishes matching after in fact segmentation being carried out to the total length edge curve of rolled piece.Make counting of one-sided edge curve on each section of rolled piece be 10, then, during the 9th passes, video camera gathers numerical point for 5 times and is followed successively by respectively:

The numerical point of (a) first time sampling

$\left\{\begin{array}{c}\left(\mathrm{800,0}\right),(748,-500),(730,-1000),(713,-1500),(696,-2000),\\ (681,-2500),(667,-3000),(655,-3500),(646,-4000),(640,-4500)\end{array}\right\}$

Least square method is utilized to gather and the numerical point processed carries out matching, to obtain the function of curve milling train outlet side video camera first time during the 9th passes.First paragraph curve is considered as opening upwards or downward second-degree parabola curve carries out matching.If fitting function expression formula be:

Order above formula will be substituted into by sample magnitude point for the first time, then have following equation group:

$\left\{\begin{array}{c}{a}_9^1\&CenterDot;{800}^2+b_9^1\&CenterDot;800+c_9^1=0\\ a_9^1\&CenterDot;{748}^2+b_9^1\&CenterDot;0.748+c_9^1=-500\\ a_9^1\&CenterDot;{730}^2+b_9^1\&CenterDot;730+c_9^1=-1000\\ a_9^1\&CenterDot;{713}^2+b_9^1\&CenterDot;713+c_9^1=-1500\\ a_9^1\&CenterDot;{696}^2+b_9^1\&CenterDot;696+c_9^1=-2000\\ a_9^1\&CenterDot;{681}^2+b_9^1\&CenterDot;681+c_9^1=-2500\\ a_9^1\&CenterDot;{667}^2+b_9^1\&CenterDot;667+c_9^1=-3000\\ a_9^1\&CenterDot;{655}^2+b_9^1\&CenterDot;655+c_9^1=-3500\\ a_9^1\&CenterDot;{646}^2+b_9^1\&CenterDot;646+c_9^1=-4000\\ a_9^1\&CenterDot;{640}^2+b_9^1\&CenterDot;640+c_9^1=-4500\end{array}\right.$

Order when error sum of squares Q reaches minimum value be best fit approximation solution.Substitute into the numerical value of each point, and can be obtained by the necessary condition of Function Extreme Value:

$\left[\begin{array}{ccc}10& 6976& 4889780\\ 6976& 4889780& 3444450340\\ 4889780& 3444450340& 2438712779156\end{array}\right]\left[\begin{array}{c}{c}_9^1\\ b_9^1\\ a_9^1\end{array}\right]=\left[\begin{array}{c}-22500\\ -15025500\\ -10052158500\end{array}\right]$

Solve this ternary linear function group, $a_9^1=-0.1454,b_9^1=236.6,c_9^1=-96204.76.$ Then the function of this section of curve is:

y＝-0.1454x ²+236.6x-96204.76

In above formula, domain of definition x ∈ [640,800], codomain y ∈ [-4500,0].

The numerical point of (b) second time sampling

$\left\{\begin{array}{c}(635,-5000),(627,-5500),(621,-6000),(616,-6500),(612,-7000),\\ (608,-7500),(605,-8000),(603,-8500),(602,-9000),(601,-9500)\end{array}\right\}$

Substitute into the numerical value of each point, and can be obtained by the necessary condition of Function Extreme Value:

$\left[\begin{array}{ccc}10& 6130& 3758898\\ 6130& 3758898& 2305694716\\ 3758898& 2305694716& 1414769956038\end{array}\right]\left[\begin{array}{c}{c}_9^1\\ b_9^1\\ a_9^1\end{array}\right]=\left[\begin{array}{c}-72500\\ -44290500\\ -27064854500\end{array}\right]$

Solve this ternary linear function group, $a_9^2=-3.1927,b_9^2=4064.48314,c_9^2=-1298674.8.$ Then the function of this section of curve is:

y＝-3.1927x ²+4064.48314x-1298674.8

In above formula, domain of definition x ∈ [601,635], codomain y ∈ [-9500 ,-5000].

The numerical point of (c) third time sampling

$\left\{\begin{array}{c}(601.2,-10000),(600.4,-10500),(598.8,-11000),(598.1,-11500),(597.7,-12000),\\ (597.8,-12500),(598.1,-13000),(598.8,-13500),(600.4,-14000),(601.2,-14500)\end{array}\right\}$

Substitute into the numerical value of each point, and can be obtained by the necessary condition of Function Extreme Value:

$\left[\begin{array}{ccc}10& 5992.5& 3591023.43\\ 5992.5& 3591023.43& 2151942137.595\\ 3591023.43& 2151942137.595& 1289570521513.8195\end{array}\right]\left[\begin{array}{c}{c}_9^1\\ b_9^1\\ a_9^1\end{array}\right]=\left[\begin{array}{c}-122500\\ -73408150\\ -43990066905\end{array}\right]$

Solve this ternary linear function group, $a_9^3=7.952,b_9^3=-9535.3932,c_9^3=2846252.5436.$ Then the function of this section of curve is:

y＝7.952x ²-9535.3932x+2846252.5436

In above formula, domain of definition x ∈ [597.7,601.1], codomain y ∈ [-14500 ,-10000].

The numerical point of (d) the 4th sampling

$\left\{\begin{array}{c}(601,-15000),(602,-15500),(603,-16000),(605,-16500),(608,-17000),\\ (612,-17500),(616,-18000),(621,-18500),(627,-19000),(635,-19500)\end{array}\right\}$

Substitute into the numerical value of each point, and can be obtained by the necessary condition of Function Extreme Value:

$\left[\begin{array}{ccc}10& 6130& 3758898\\ 6130& 3758898& 2305694716\\ 3758898& 2305694716& 1414769956038\end{array}\right]\left[\begin{array}{c}{c}_9^1\\ b_9^1\\ a_9^1\end{array}\right]=\left[\begin{array}{c}-172500\\ -105894500\\ -65028146500\end{array}\right]$

Solve this ternary linear function group, $a_9^4=3.2389,b_9^4=-4121.477,c_9^4=1291407.62696.$ Then the function of this section of curve is:

y＝3.2389x ²-4121.477x+1291407.62696

In above formula, domain of definition x ∈ [601,635], codomain y ∈ [-19500 ,-15000].

The numerical point of (e) the 5th sampling

$\left\{\begin{array}{c}(640,-20000),(646,-20500),(655,-21000),(667,-21500),(681,-22000),\\ (696,-22500),(713,-23000),(730,-23500),(748,-24000),(800,-24500)\end{array}\right\}$

Substitute into the numerical value of each point, and can be obtained by the necessary condition of Function Extreme Value:

$\left[\begin{array}{ccc}10& 6976& 4889780\\ 6976& 4889780& 3444450340\\ 4889780& 3444450340& 2438712779156\end{array}\right]\left[\begin{array}{c}{c}_9^1\\ b_9^1\\ a_9^1\end{array}\right]=\left[\begin{array}{c}-222500\\ -155886500\\ -109747451500\end{array}\right]$

Solve this ternary linear function group, $a_9^5=0.148957,b_9^5=-241.686,c_9^5=73513.4577.$ Then the function of this section of curve is:

y＝0.148957x ²-241.686x+73513.4577

In above formula, domain of definition x ∈ [640,800], codomain y ∈ [-24500 ,-20000].

Because on rolled piece total length direction, width remains unchanged substantially, can assert that rolled piece fore side edge curve shape should be identical with transmission side edge curve shape.

(4) rolled piece edge curve and rolling centerline angle (i.e. lateral bending angle) calculate

Below the angle (i.e. lateral bending angle) that the rolled piece transmission side edge curve of the 9th passage first time sampling and the parallel lines of rolling centerline intersect at each numerical point place is calculated.First right the lateral bending angle at place is calculated as follows:

In like manner can obtain the lateral bending angle at other each numerical point places:

The angle mean value of the 9th passage first time sampling curve for:

In like manner, the lateral bending angle mean value of its second to five sampling curves is respectively:

(5) determination methods in rolled piece lateral bending direction

(a) due to then the lateral bending walking direction of the 9th passage first time sampling curve is as follows:

Function is y=-0.1454x ²+ 236.6x-96204.76, symmetry axis is:

$x=-\frac{236.6}{2\&times;(-0.1454)}=813.618$

Because the abscissa value of sampled point is all less than 813.618, and open Side Down for illustrative graph, and lateral bending direction is fore side, therefore belongs to situation 1.

(b) due to therefore situation 5 is belonged to.

(c) due to therefore situation 5 is belonged to.

(d) due to therefore situation 5 is belonged to.

(e) due to then the lateral bending walking direction of the 9th road order five sampling curves is as follows:

Function is y=0.148957x ²-241.686x+73513.4577, symmetry axis is:

$x=-\frac{-241.686}{2\&times;0.148957}=811.26$

Because the abscissa value of sampled point is all less than 811.26, and the opening upwards of illustrative graph, lateral bending direction is fore side, therefore belongs to situation 3.

Comprehensive above analysis is known, and the edge of rolled piece bends the situation belonging to situation 1 → situation 5 → situation 3, and illustrate that rolled piece is after the 9th passes completes, and defines C type lateral bending, lateral bending direction is fore side.

Step 3: based on the roll gap mathematic interpolation in rolled piece lateral bending angle and lateral bending direction

Suppose that the transmission side roll gap at the end of the 9th passes is 72.63mm, fore side roll gap is 72.56mm, then bilateral roll gap difference is:

Δs ₉＝72.63-72.56＝0.07mm

Therefore the roll gap difference setting the 10th passage is:

Δs ₁₀＝0.07+t ₁₀

Wherein t ₁₀it is the roll gap deviation adjusting amount of the 10th passage.

Step 4: presetting between the passage of roll gap difference

Owing to being judged as C type lateral bending, then the roll gap difference in the 10th rolling pass can be set as steady state value, due to then then then Δ s ₁₀be calculated as:

$\mathrm{\&Delta;}{s}_{10}=0.07+\frac{1}{2}(0.1f_0+0.1f_0)=0.07+0.1f_0=0.17$

Wherein f ₀for the initial value of roll gap difference Dynamic gene, because its lateral bending direction is fore side, and front 8 passages judge all not occur lateral bending situation, and therefore initial value design is 1.

Step 5: self-adjusting in the passage of roll gap difference

In the operation of rolling of the 10th passage, obtain rolled piece edge curve according to the real time feedback image of milling train outlet side video camera, sampling length is still 5m, then is controlled by the part of not rolling of rolled piece edge actual curve to rolled piece, if rolled piece is to transmission side lateral bending, then reduce bilateral roll gap difference; If rolled piece is to fore side lateral bending, then increase bilateral roll gap difference.Suppose that the 10th passage rolled piece outlet length is 35m, then the number of times i sampled ₁₀for i ₁₀=35/5=7.Then illustrate in the 10th passes process, need do roll gap difference and judge whether for 7 times to need adjustment roll gap difference.Suppose presetting through between the passage of roll gap difference after, first time, the actual lateral bending direction detecting rolled piece still be fore side, and the absolute value at lateral bending angle still interval [2 °, 15 °) in, then the actual value of the 10th passage roll gap difference for the first time after self adaptation is:

$\mathrm{\&Delta;}{s}_{10}^{1\&prime;}=\mathrm{\&Delta;}{s}_{10}+\mathrm{\&Delta;}{t}_{10}^1=\mathrm{\&Delta;}{s}_{10}+0.005g=0.17+0.05=0.22\mathrm{mm}$

The actual lateral bending angle detecting rolled piece of second time is less than 2 °, then roll gap difference is still 0.22mm.Self adaptation trim values is 0. third time, the actual lateral bending angle detecting rolled piece was less than 2 °, then roll gap difference is still 0.22mm.Self adaptation trim values is 0. 4th time the actual lateral bending angle detecting rolled piece is less than 2 °, then roll gap difference is still 0.22mm.Self adaptation trim values is 0. the lateral bending angle of the actual detection rolled piece of follow-up each time is all less than 2 °.

Wherein, g is Adaptive Adjustment of Step Length, and-10≤g≤10, get g=10 in above formula.

Step 6: the self study of the presetting Dynamic gene f of roll gap difference

Consider to adopt the presetting Dynamic gene f of the roll gap difference of exponential smoothing to the 9th passage to carry out self study.By the actual roll gap deviate Δ s after self adaptation ₁₀' carry out inverse, the scope due to lateral bending angle is 2 °≤α < 15 °, and if only if lateral bending angle roll gap difference self adaptation when 2 °≤α < 15 ° regulates, it is right therefore only to need upgrade.Calculate presetting Dynamic gene absolute value be:

$\left|f_{9a}^{*}\right|=\left|\frac{\mathrm{\&Delta;}{s_{10}}^{\&prime;}-\mathrm{\&Delta;}{s}_9}{0.1}\right|=\left|\frac{0.22-0.07}{0.1}\right|=1.5$

The then presetting Dynamic gene f of the 10th passage _10aabsolute value be:

$\left|f_{10a}\right|=|f_{9a}+\mathrm{\&beta;}(f_{9a}^{*}-f_{9a})|=|1+0.5(1.5-1)|=1.25$

Wherein, f _ninitial value be ± 1, still should judge that it is plus or minus according to the lateral bending direction of rolled piece.β is gain coefficient, gets β=0.5.

Detailed description of the invention two

Suppose in present embodiment step 2 through judging, the edge of rolled piece bends the situation belonging to situation 2 → situation 5 → situation 3, and illustrate that rolled piece is after the 9th passes completes, define S type lateral bending, lateral bending direction is for bend towards transmission side gradually by fore side.The account form of step one is identical with detailed description of the invention one.

Step 3: based on the roll gap mathematic interpolation in rolled piece lateral bending angle and lateral bending direction

Suppose that the transmission side roll gap at the end of the 9th passes is 72.63mm, fore side roll gap is 72.56mm, then bilateral roll gap difference is:

Δs ₉＝72.63-72.56＝0.07mm

The roll gap difference setting the 10th passage is:

Δs ₁₀＝0.07+t ₁₀

Wherein t ₁₀it is the roll gap deviation adjusting amount of the 10th passage.

Step 4: presetting between the passage of roll gap difference

Suppose that the 10th passage rolled piece outlet length is 35m, then the number of times i sampled ₁₀for i ₁₀=35/5=7.Owing to being judged as S type lateral bending, then the roll gap difference in the 10th rolling pass is two numerical value, when rolled piece is rolled to centre, is transformed to another roll gap difference by a roll gap difference.Due to and rolled piece lateral bending direction is fore side, then f ₀=1; and rolled piece lateral bending direction is transmission side, then f ₀=-1.Then be calculated as:

$\mathrm{\&Delta;}{s}_{10}^1=0.07+0.25\&times;1=0.32\mathrm{mm}$

be calculated as:

$\mathrm{\&Delta;}{s}_{10}^5=0.07-0.1\&times;1=-0.03\mathrm{mm}$

Then before the 10th passage, the roll gap deviation setting of 17.5m is rear 17.5m roll gap deviation setting is $\mathrm{\&Delta;}{s}_{10}^5=-0.03\mathrm{mm}.$

Suppose that the roll linear velocity of milling train is 1500mm/s, roll diameter of roller is 1000mm, and the advancing slip value of the 10th passes is 0.0677, and drafts is 30mm, and the length that roll surface when rolled piece outlet length is 17.5m turns over is:

$L_{r10}=\frac{17500}{1+0.0677}+\sqrt{30\&times;1000}=16563.57\mathrm{mm}$

Then from milling train is nipped start timing to roll gap deviation by become time P ₁₀for:

$P_{10}=\frac{16563.57/2}{1500}=5.52s$

Step 5: self-adjusting in the passage of roll gap difference

In the operation of rolling of the 10th passage, obtain rolled piece edge curve according to the real time feedback image of milling train outlet side video camera, sampling length is still 5m, then is controlled by the part of not rolling of rolled piece edge actual curve to rolled piece, if rolled piece is to transmission side lateral bending, then reduce bilateral roll gap difference; If rolled piece is to fore side lateral bending, then increase bilateral roll gap difference.In 10th passes process, need do roll gap difference and judge whether for 7 times to need adjustment roll gap difference.Suppose presetting through between the passage of roll gap difference after, first time, the actual lateral bending direction detecting rolled piece still be fore side, and the absolute value at lateral bending angle still interval [2 °, 15 °) in, then the actual value of the 10th passage roll gap difference for the first time after self adaptation is:

$\mathrm{\&Delta;}{s}_{10}^{1\&prime;}=\mathrm{\&Delta;}{s}_{10}+\mathrm{\&Delta;}{t}_{10}^1=\mathrm{\&Delta;}{s}_{10}+0.005g=0.32+0.05=0.37\mathrm{mm}$

The actual lateral bending angle detecting rolled piece of second time is less than 2 °, then roll gap difference is still 0.37mm.Self adaptation trim values is 0. third time, the actual lateral bending angle detecting rolled piece was less than 2 °, then roll gap difference is still 0.37mm.Self adaptation trim values is 0. 4th time the actual lateral bending angle detecting rolled piece is less than 2 °, then roll gap difference is still 0.37mm.Self adaptation trim values is 0. when being rolled to 17.5m, roll gap difference is adjusted to-0.03mm automatically.5th time the actual lateral bending angle detecting rolled piece is less than 2 °, and roll gap difference is-0.03mm.6th time the actual lateral bending angle detecting rolled piece is less than 2 °, and roll gap difference is still-0.03mm.7th time the actual lateral bending angle detecting rolled piece is less than 2 °, and roll gap difference is still-0.03mm.

Wherein, g is Adaptive Adjustment of Step Length, and-10≤g≤10, get g=10 in above formula.

Step 6: the self study of the presetting Dynamic gene f of roll gap difference

Consider to adopt the presetting Dynamic gene f of the roll gap difference of exponential smoothing to the 9th passage to carry out self study.By the actual roll gap deviate Δ s after self adaptation ₁₀' carry out inverse, the scope due to lateral bending angle is 15 °≤α < 25 °, and if only if lateral bending angle roll gap difference self adaptation when 15 °≤α < 25 ° regulates, it is right therefore only to need upgrade.Presetting Dynamic gene can be obtained absolute value be:

$\left|f_{9b}^{*}\right|=\left|\frac{\mathrm{\&Delta;}{s_{10}}^{\&prime;}-\mathrm{\&Delta;}{s}_9}{0.25}\right|=\left|\frac{0.37-0.07}{0.25}\right|=1.2$

The then presetting Dynamic gene f of the 10th passage _10babsolute value be:

$\left|f_{10b}\right|=|f_{9b}+\mathrm{\&beta;}(f_{9b}^{*}-f_{9b})|=|1+0.5(1.2-1)|=1.1$

Wherein, f _9aand f _9binitial value be 1, still should judge that it is plus or minus according to the lateral bending direction of rolled piece.β is gain coefficient, gets β=0.5.

Claims (6)

1. overcoming the method producing lateral bending in sheet material rough rolling process, it is characterized in that, considering the lateral bending defect eliminating rolled piece by automatically adjusting milling train bilateral roll gap deviate, adopt following steps to realize:

Steps A: the detection of lateral bending;

Step B: the lateral bending angle detected based on lateral bending and the calculating in lateral bending direction;

Step C: based on the roll gap mathematic interpolation in rolled piece lateral bending angle and lateral bending direction;

Step D: presetting between the passage of roll gap difference;

Step e: self-adjusting in the passage of roll gap difference;

Step F: the self study of the presetting Dynamic gene f of roll gap difference.

2. according to claim 1ly overcome the method producing lateral bending in sheet material rough rolling process, it is characterized in that, the computational methods in step B lateral bending angle and lateral bending direction are as follows:

(1) video camera is sampled and is processed the calculating of cycle of images

When rolled piece is at the n-th passes, if n is odd number, then mean that rolled piece is from rolling after machine forward direction machine, the positive direction indication of the X-axis in this definable figure tri-is fore side, the negative direction indication of X-axis is transmission side, and Y-axis positive direction indication is after machine, and Y-axis negative direction indication is before machine, now the image of the industrial CCD camera acquisition after machine is processed, suppose that the practical rolling speed of milling train is V _n, unit is mm/second, records by the speed measuring coder be arranged on driving motor, then the muzzle velocity of band is v _n, unit is mm/second:

v _n＝V _n·(1+S _n)

S _nbe the advancing slip value of rolling n-th passage, its algorithm is as follows:

Wherein, R is roller radius, and unit is millimeter; H _nfor the exit thickness of rolling n-th passage, unit is millimeter; H _n-1for the exit thickness of rolling (n-1)th passage, be also the inlet thickness of rolling n-th passage, unit is millimeter;

Industrial CCD video camera can be chosen along the surveyed area length L on length of rolled piece direction _de(work as L _dewhen≤5) be a curvature estimation cycle, or (work as 5<L _dewhen≤10) be a curvature estimation cycle, with L _dethe situation of≤5 is example, industrial CCD camera acquisition the cycle processing image is S (unit is second) is:

This shows that the length of the rolled piece gathered each time in image does not all have lap, the adjacent image gathered is that rolled piece goes up adjacent part along its length just, only by the Images uniting of all collections in a rolling pass within a coordinate system, need can obtain the curve of rolled piece side total length;

(2) the rolled piece hop count based on image sampling and treatment cycle calculates

Make to set up data communication between the computer system of the PLC system of control milling train and sampling and processing image, to ensure when the mill speed in a passage changes, i.e. v _nwhen changing, to gather and the cycle K processing image also changes thereupon, suppose that the rolled piece outlet length of the n-th passes is L _n, the hop count that this passage rolled piece is divided into is i, then the computational methods of i are:

If i is decimal, then its value is rounded up;

The subsection curve drafting of (3) n-th passage rolled pieces

The edge numerical point of the rolled piece of the n-th passes is carried out curve fitting, because rolled piece has been divided into i section, matching is distinguished after then in fact segmentation being carried out to the total length edge curve of rolled piece, that supposes one-sided edge curve on each section of rolled piece counts as m, the scope of desirable m is 10≤m≤20, then during the n-th passes, the set of the numerical point of rolled piece transmission side (analyzing for transmission side) the edge image curve that video camera first time collects after machine is: the edge numerical point set that video camera collects in milling train exit for the p time is wherein p≤i _n; i _nwhen being the n-th passes, the divided hop count of rolled piece, because on rolled piece total length direction, width remains unchanged substantially, can assert that rolled piece fore side edge curve shape should be identical with transmission side edge curve shape; When adopting least square method to the n-th passes, milling train outlet side video camera first time gathers and the numerical point processed carries out matching, to obtain the function of curve; Due to L _de≤ 5m, according to rolling general knowledge, within the scope of this, the edge of rolled piece may be cubic curve hardly, can not be also curve opening parabola to the left or to the right, work as L _delikely there are above two kinds of curves during > 5m, even if there is cubic curve or opening parabola to the left and right, because its curvature is very little, also should not control accordingly for this curve, so opening upwards only need be regarded as or downward second-degree parabola curve carries out matching, if fitting function expression formula be:

Order then there is following equation group:

Order when error sum of squares Q reaches minimum with value be best fit approximation solution, can be derived by the necessary condition of Function Extreme Value draws following matrix equation:

Due to with known, this is a system of linear equations with three unknown numbers, three equations, the unknown number in solving equation group with its best fit approximation solution can be obtained, in like manner, can try to achieve best fit approximation solution, so far, the conic section function of all m sections after the n-th passes can be obtained, rolled piece in the n-th passage, the p time sampling section the edge curvilinear function domain of definition be

(4) rolled piece edge curve and rolling centerline angle calcu-lation

Each section of process of sampling by milling train and through video camera successively on rolled piece, wherein dash area represents the region that current camera is being sampled, the positive direction of Y-axis is rolling direction, video camera sampling process comprises: first time sampling, second time sampling, third time sampling, 4th sampling, the rest may be inferred, until terminate i-th sampling of rolled piece, gather angle between image edge conic section and rolling centerline to the n-th passage first time below to calculate, six kinds of situations are divided to consider, below the angle that the rolled piece transmission side edge curve of the n-th passage first time sampling and the parallel lines of rolling centerline intersect at each numerical point place is calculated,

Can obtain quadratic function differentiate:

Will substitution above formula can obtain curve and exist place's tangent slope is:

Then the angle (i.e. lateral bending angle) of this tangent line and rolling centerline is:

In like manner can obtain the angle at other each numerical point places the then angle mean value of the n-th passage first time sampled point for:

referred to as the lateral bending angle of rolled piece part in image during the n-th passage first time sampling, then the lateral bending angle set of the n-th passage rolled piece is

(5) determination methods in rolled piece lateral bending direction

Conic section function after matching is symmetry axis is following 6 kinds of situations are divided into judge:

If a. judge in all numerical points be all less than and when time parabola Open Side Down, illustrate that the lateral bending direction of rolled piece is fore side, belong to situation 1;

If b. judge in all numerical points be all greater than and when time parabola Open Side Down, illustrate that the lateral bending direction of rolled piece is transmission side, belong to situation 2;

If c. judge in all numerical points be all less than and when time parabola opening upwards, illustrate that the lateral bending direction of rolled piece is fore side, belong to situation 3;

If d. judge in all numerical points be all greater than and when time parabola opening upwards, illustrate that the lateral bending direction of rolled piece is transmission side, belong to situation 4;

E. when time, unification is considered as situation 5;

If f. judge middle component values point is less than component values point is greater than then illustrate that the lateral bending degree of this part on rolled piece is excessive, cannot be controlled by adjustment roll gap difference, can only consider to excise this part.

3. according to claim 2ly overcome the method producing lateral bending in sheet material rough rolling process, it is characterized in that, step C is as follows based on the roll gap mathematic interpolation method in rolled piece lateral bending angle and lateral bending direction:

Suppose that Δ s is that milling train bilateral roll gap is poor, unit is millimeter, and its computational methods are:

Δs＝s _ds-s _os

Wherein s _dsfor transmission side roll gap, s _osfor fore side roll gap, unit is millimeter;

When supposing to detect that lateral bending phenomenon appears in a time rolled piece, as-2 ° of < α < 2 °, roll gap difference does not make any adjustments, and is Δ s=Δ s ⁱ+ t=Δ s ⁱ+ 0=Δ s ⁱ; As 2 °≤α < 15 ° or-15 °≤α <-2 °, setting roll gap difference Δ s=Δ s ⁱ+ t=Δ s ⁱ+ 0.1f; As 15 °≤α < 25 ° or-25 °≤α <-15 °, setting roll gap difference Δ s=Δ s ⁱ+ 0.25f; As 25 °≤α < 35 ° or-35 °≤α <-25 °, setting roll gap difference Δ s=Δ s ⁱ+ 0.5f; As 35 °≤α < 45 ° or-45 °≤α <-35 °, setting roll gap difference Δ s=Δ s ⁱ+ 0.8f; When 45 °≤α or α≤-45 °, should consider to excise leg portion, and the method provided in this patent can not be provided, wherein f is roll gap difference Dynamic gene, its span is-2≤f≤2, initial value is ± 1, and when lateral bending direction is transmission side, initial value is taken as-1, and when lateral bending direction is fore side, initial value is taken as 1; T is roll gap difference adjustment amount, and unit is millimeter, when rolled piece lateral bending being detected first, and Δ s ⁱfor the original roll gap difference of mill personnel after carrying out mill roll-gap leveling, unit is millimeter, ideally Δ s ₀=0; When non-rolled piece lateral bending detected first time, Δ s ⁱfor the actual roll gap deviate at the end of upper a time rolling; The size of f value is determined by the lateral bending angle of rolled piece, and lateral bending angle is larger, then the absolute value of f is larger, and the symbol of f value is determined by the lateral bending direction of rolled piece, when lateral bending direction is fore side, f be on the occasion of, lateral bending direction is transmission side, and f is negative value.

4. according to claim 3ly overcome the method producing lateral bending in sheet material rough rolling process, it is characterized in that, between the passage of step D roll gap difference, presetting method is as follows:

According to the testing result of upper a time rolled piece lateral bending degree, the combination collocation situation of described situation 1-6 and the numerical value at lateral bending angle, judge that this lateral bending belongs to the lateral bending of which type and the degree of lateral bending, and the bilateral roll gap difference of lower a time is set, to i sampled all in the n-th rolling pass _nsection rolled piece edge curve carries out lateral bending walking direction, according to sampling order successively, then occurs that following situation is judged as C type lateral bending when combining:

(1) situation 1 → situation 5 → situation 3

(2) situation 2 → situation 5 → situation 4

Occur that following situation is judged as L-type lateral bending when combining:

(3) situation 5 → situation 3

(4) situation 5 → situation 4

(5) situation 1 → situation 5

(6) situation 2 → situation 5

Occur that following situation is judged as S type lateral bending when combining:

(7) situation 1 → situation 5 → situation 4

(8) situation 2 → situation 5 → situation 3

After n-th rolling terminates, if be judged as C type lateral bending, then the roll gap difference in the (n+1)th rolling pass can be set as steady state value, namely wherein it is the n-th passage i-th _nthe actual roll gap difference of section, known with can obtain with then Δ s _n+1;

After n-th rolling terminates, if be judged as L-type or S type lateral bending, roll gap difference then in the (n+1)th rolling pass is changing value, when being judged as L-type lateral bending, the section being only not less than 2 ° at lateral bending angle carries out the adjustment of roll gap difference, and other sections being less than 2 ° still return to the roll gap difference at the end of the n-th passage, when being judged as S type lateral bending, the outlet length of the (n+1)th rolling pass rolled piece is divided into two sections, and the last period regulates direction just in time contrary with the roll gap difference of latter a section, i.e. t _n+1numerical value become negative from positive number, or become positive number from negative, its size is determined by lateral bending angle;

Suppose that the length that the (n+1)th passage rolls rear rolled piece is L _n+1, unit is millimeter, and this value can be determined according to constant-volume principle in the rolled piece operation of rolling, and in the (n+1)th passes process, the length that roll surface turns over is L _{r (n+1)}, unit is millimeter:

Wherein S _n+1it is the advancing slip value of the (n+1)th passage; Δ h _n+1be the drafts of the (n+1)th passage, unit is millimeter; R is the radius of roll, and unit is millimeter;

When being judged as L-type lateral bending, suppose the z near mill portion on the n-th passage outlet rolled piece _n+1section lateral bending angle is all not less than 2 °, and remainder lateral bending angle is all less than 2 °, then as rolled piece timing P from nipping _n+1after second, bilateral roll gap deviate returns to the roll gap difference at the end of the n-th passage; P _n+1unit is second, and its computational methods are:

Suppose the z away from mill portion on the n-th passage outlet rolled piece _n+1section lateral bending angle is all not less than 2 °, and remainder lateral bending angle is all less than 2 °; Then as rolled piece timing P from nipping _n+1after second, bilateral roll gap deviate is adjusted to the pre-set value of the n-th passage by the roll gap difference at the end of the n-th passage, P _n+1unit is second, and its computational methods are:

When being judged as S type lateral bending, suppose that the rolled piece muzzle velocity of the (n+1)th passage is v _n+1, unit is mm/second; The linear velocity of roll is V _n+1, unit is mm/second, then as rolled piece timing P from nipping _n+1after second, the adjustment direction of bilateral roll gap deviate changes, i.e. t _n+1numerical value start to become negative from positive number, or become positive number from negative, P _n+1unit is second, and its computational methods are:

5. according to claim 4ly overcome the method producing lateral bending in sheet material rough rolling process, it is characterized in that, in the passage of step e roll gap difference, self-regulating method is as follows:

In a passage during rolling, according to the real time feedback image of milling train exit camera, on basis presetting between passage, carry out the self adaptation fine setting of bilateral roll gap difference, presetting roll gap difference is in the actual operation of rolling, occur sometimes roll gap tilt quantity cannot eliminate within lateral bending to allowed band not or the excessive rolled piece that causes that tilts to the situation of another direction lateral bending, therefore the roll gap difference self adaptation fine setting in passage just seems and is even more important, and supposes that the adaptive trim values of the n-th passage roll gap difference is rolling passage need adjust i _nsecondary, when detecting that rolled piece lateral bending direction is fore side, Δ t _nfor on the occasion of, lateral bending direction is transmission side, Δ t _nfor negative value, this value is superimposed upon in presetting roll gap difference, supposes that the actual roll gap deviate after superposing is Δ s ' _n, unit is millimeter, Δ t _ncomputational methods as follows:

As-2 ° of < α < 2 °, roll gap difference does not make any adjustments, and is Δ t=0, without the need to intervening roll gap difference; As 2 °≤α < 15 ° or-15 °≤α <-2 °, roll gap difference adaptation value Δ t=0.005g millimeter; As 15 °≤α < 25 ° or-25 °≤α <-15 °, roll gap difference adaptation value Δ t=0.01g millimeter; As 25 °≤α < 35 ° or-35 °≤α <-25 °, roll gap difference adaptation value Δ t=0.015g millimeter; As 35 °≤α < 45 ° or-45 °≤α <-35 °, roll gap difference adaptation value Δ t=0.02g millimeter; When 45 °≤α or α≤-45 °, should consider to excise leg portion, and can not adopt the method provided in this patent, wherein, g is Adaptive Adjustment of Step Length ,-10≤g≤10, when detecting that rolled piece lateral bending direction is fore side, g be on the occasion of; When lateral bending direction is transmission side, g is negative value.

6. according to claim 5ly overcome the method producing lateral bending in sheet material rough rolling process, it is characterized in that, the self-learning method of step F roll gap difference presetting Dynamic gene f is as follows:

Consider adopt exponential smoothing to the n-th passage roll gap difference presetting Dynamic gene f carry out self study by the actual roll gap deviate Δ s ' after self adaptation _ncarry out inverse, presetting Dynamic gene can be obtained absolute value be:

Wherein for carrying out inverse by actual roll gap deviation, lateral bending angle interval [2 °, 15 °) or [-15 ° ,-2 °) interior time presetting Dynamic gene; for carrying out inverse by actual roll gap deviation, lateral bending angle interval [15 °, 25 °) or [-25 ° ,-15 °) in time presetting Dynamic gene; for carrying out inverse by actual roll gap deviation, lateral bending angle interval [25 °, 35 °) or [-35 ° ,-25 °) in time presetting Dynamic gene; for carrying out inverse by actual roll gap deviation, lateral bending angle interval [35 °, 45 °) or [-45 ° ,-35 °) in time presetting Dynamic gene,

The then presetting Dynamic gene f of the (n+1)th passage _n+1absolute value be:

Wherein, if all non-self study of the presetting Dynamic gene of front n passage, then f _na, f _nb, f _nc, f _ndinitial value be ± 1, still should judge that it is plus or minus according to the lateral bending direction of rolled piece; β is gain coefficient, 0≤β≤1; f _{(n+1) a}for lateral bending angle interval [2 °, 15 °) or [-15 ° ,-2 °) interior time presetting Dynamic gene; for lateral bending angle interval [15 °, 25 °) or [-25 ° ,-15 °) interior time presetting Dynamic gene; for lateral bending angle interval [25 °, 35 °) or [-35 ° ,-25 °) in time presetting Dynamic gene; for lateral bending angle interval [35 °, 45 °) or [-45 ° ,-35 °) in time presetting Dynamic gene, when the lateral bending angle numerical value of certain section of edge curve on rolled piece falls into [2 °, interval, 15 °), [15 °, 25 °), [25 °, 35 °), [35 °, 45 °), [-15 °,-2 °), [-25 ° ,-15 °), [-35 ° ,-25 °), [-45 °,-35 °) time, then according to upper two formulas respectively to f _nnumerical value carry out self study and upgrade, if judge lateral bending angle not in above each interval, then f _nnumerical value does not carry out self study.