CN102756013B - Improving method and device for warping of cold-rolled strip steel - Google Patents

Abstract

The invention relates to an improving method for the warping of cold-rolled strip steel. A warping control device is arranged at an outlet of a temper mill. The improving method is characterized in that a roll A and a fixing roll B are respectively taken as an upper roll and a lower roll of the warping control device, wherein the height of the roll A can be adjusted in the vertical direction, the improving method comprises the following steps of: 1. collecting the equipment parameters of the temper mill, and determining the distance between the temper mill and a BQK device; 2. determining the equipment parameters of the BQK device, and mainly determining the diameter of the roll A; 3. collecting the characteristic parameters of flattening strip steel, wherein the characteristic parameters comprise Young modulus of strip steel to be flattened and the thickness and width of the strip steel; 4. measuring the warping height delta H of the flattening strip steel at the exit; 5. calculating the cutting depth d of the roll A of the BQK device according to delta H=k4*sina2(b(K1d2+k2d+C)/2h)*(h/(k1d2+k2d+C); and 6. adjusting the height of the roll A according to the calculated cutting depth d. According to the improving method, the control effects of two warping control technologies for straightening and adjusting rolling wrap angles are simultaneously realized, thereby eliminating the warping defect of the flattened strip steel at high efficiency.

Description

A kind of improvement method and device of cold-strip steel warpage

Technical field

The present invention relates to metallurgy rolling field, concrete, the present invention relates to a kind of improvement method and device of cold-strip steel warpage.

Background technology

Strip, as one of most important product of steel and iron industry, plays very important effect in the national economic development.It has application extremely widely in industry, agricultural, national defence and daily life.Along with developing rapidly of modern industry and science and technology, the users of industrial enterprise have proposed more and more stricter requirement to the quality of Strip.

Warpage and plate shape are to weigh one of important indicator with steel shape.In recent years, along with the development of plate shape theory and plate shape control technology is perfect, obtain considerable raising with the plate shape level of steel, substantially can meet user's requirement.But the development with steel warpage control technology is but very slow, present stage, the warpage defect of cold-strip steel has become the cold rolling production of puzzlement and has particularly rolled one of main Quality of rear subsequent treatment production.

Comprise that C sticks up, L sticks up, turn round and stick up etc. with the warpage defective form of steel, it produces reason is that inside exists certain inhomogeneous residual stress, after it reaches the Instability condition with steel, warpage will occur.Strip production development is to today, and the technology that is specifically designed to warpage control is not a lot, mainly occurs following three kinds of control technologys:

● straightener control warpage

● stretching-bending straightener control warpage

● change planisher cornerite control warpage

In means in above-mentioned three kinds of controls with steel warpage, straightener is identical with the control principle of withdrawal straightening machine, controls effect obvious, and still, shortcoming is to need a special process procedure and the relevant major-minor equipment of increasing, and invests larger.The Baosteel patent No. 200520043022.2 once proposed a kind of anti-device that sticks up of continuous annealing unit, increase by an anti-roller that sticks up by the position apart from idler roller close together and realize the band steel warpage straightening mechanism that is similar to straightening function, shown in Fig. 1, its scheme is identical with independent aligning principle, drop into relatively little, but because cornerite is less, and lack recurvation link, therefore control effect limited.

The cornerite of the change formation process passing through theoretically, can directly change the relative deformation degree with steel upper and lower surface.But because planisher cornerite adjustable range is less, it is very limited that therefore these means are improved effect with steel warpage.

Summary of the invention

For overcoming the problems referred to above, the object of the invention is to: improvement method and device that a kind of cold-strip steel warpage is provided, according to improvement method and the device of cold-strip steel warpage of the present invention, aligning is combined with the technical advantage that changes rolling cornerite, develop a kind of special device that is arranged on milling train or planisher outlet, realize the control effect of aligning and these two kinds of warpage control technologys of adjustment rolling cornerite simultaneously, thereby efficiently eliminate the smooth rear warpage defect with steel.The design's main feature is near rolling outlet, successful; Meanwhile, adjustment equipment is simple, and small investment is taken up an area few.

For achieving the above object, technical scheme of the present invention is as follows:

A kind of improvement method of cold-strip steel warpage, it is characterized in that, warpage control device (BQK device) is set in planisher exit, and described warpage control device comprises: respectively can regulate in vertical direction roller A highly and stationary roll roller B as up-down rollers

Step 1, collects the device parameter of smooth unit, collects the distance between smooth unit and BQK device, and smooth unit and BQK device space are 30mm-3000mm from scope,

Step 2: collect the device parameter of BQK device, comprising:

The diameter of collecting A roller, the diameter D scope of roller A is as follows;

$0.1D_t\≤D\≤0.5\frac{\mathrm{\δE}}{{\mathrm{\σ}}_S}---\left(1\right)$

In formula, δ---band steel minimum thickness;

σ _s---band steel yield limit,

D _t---planisher work roll diameter,

E---Young's modulus,

The roll surface length L of roller A _ameet following relational expression:

1.1B _max≤L _A≤1.6B _max (2)

In formula, B _max---band steel Breadth Maximum,

Step 3: collect the smooth characterisitic parameter with steel, described characterisitic parameter comprises: the smooth Young's modulus with steel, thickness and the width with steel; Above-mentioned parameter is mainly used in the calculating of step 5, and wherein Young's modulus E is for calculating parameter K ₁, belt steel thickness and width are all that step 5 is calculated indispensable parameter used;

Step 4: record the depth of camber Δ H:0-200mm of smooth outlet with steel;

Step 5: according to formula

$\mathrm{\ΔH}=k_4\·{\sin }^2\left(\frac{b(K_2{d}^2+K_{2}d+C)}{2h}\right)\×\left(\frac{h}{K_1{b}^2+K_{2}d+C}\right)$

In formula, rolling cornerite changes the influence coefficient to warpage, value 0-1;

$K_2=k_1\×a-\frac{K_{3}S}{E};C=\frac{c_2}{E}-c_1,$

B---with the width of steel, m, from step 3;

E---with the Young's modulus of steel, MPa, from step 3;

D---the diameter of BQK device A roller, m;

D---the penetraction depth of BQK device A roller, m;

A---rolling cornerite is adjusted coefficient, 1/m;

H---belt steel thickness, m, from step 3;

K ₂, k ₃, c ₂---regression coefficient, span is respectively 0-5 ,-50-50,0-500;

L---BQK device is to the distance of planisher, m;

C ₁---constant term, interval is 0-1;

K ₄---influence coefficient, span-20-20.

Iterative computation goes out the penetraction depth of BQK device A roller;

Step 6: the penetraction depth d calculating according to step 5, the height of adjustment A roller.

In step 1, collect the device parameter of smooth unit, collect the distance between smooth unit and BQK device, smooth unit and BQK device space are [300mm from scope, 1000mm], select according to trying one's best close with planisher for BQK device, but ensure not interfere with planisher roller system and planisher normal operating, BQK device and planisher distance can not be excessively far away simultaneously, according to spot debugging experience, when BQK device and planisher distance is greater than after 3000mm, the regulating action rolling cornerite being regulated is very little; In step 2: the range of choice of the diameter D of roller A need to meet following relational expression guarantee band steel plastic deformation occurs when through roller A,

$0.1D_t\≤D\≤0.5\frac{\mathrm{\δE}}{{\mathrm{\σ}}_S}---\left(1\right)$

In step 3: collect the smooth characterisitic parameter with steel, described characterisitic parameter comprises: the smooth Young's modulus with steel, thickness and the width with steel.Above-mentioned parameter is mainly used in the calculating of step 5, and wherein Young's modulus E is for calculating parameter K ₁, belt steel thickness and width are all that step 5 is calculated indispensable parameter used.

In step 4: as shown in Figure 9, use is stuck up measuring instrument with steel C or by the mode of manual measurement, obtain the depth of camber Δ H (actual depth of camber with steel affected by many factors, unfixing, scope generally 0-200mm between) of smooth outlet with steel.

In step 5: according to formula

$\mathrm{\ΔH}=k_4\·{\sin }^2\left(\frac{b(K_2{d}^2+K_{2}d+C)}{2h}\right)\×\left(\frac{h}{K_1{b}^2+K_{2}d+C}\right)$

In formula, rolling cornerite changes the influence coefficient to warpage, and interval is [0,1];

$K_2=k_1\×a-\frac{K_{3}S}{E};C=\frac{c_2}{E}-c_1.$

B---with the width of steel, m, from step 3;

E---with the Young's modulus of steel, MPa, from step 3;

D---the diameter of BQK device A roller, m;

D---the penetraction depth of BQK device A roller, m;

A---rolling cornerite is adjusted coefficient, 1/m;

H---belt steel thickness, m, from step 3;

K ₂, k ₃, c ₂---regression coefficient, span is respectively [0,5], [50,50], [0,1000];

L---BQK device is to the distance of planisher, m;

C ₁---constant term, interval is [0,1];

K ₄---influence coefficient, span [20,20].

In formula, each coefficient, parameter are all that the recurrence of finite element simulation result of calculation is determined in conjunction with spot debugging experience data simultaneously.

In the time that iterative computation goes out the penetraction depth d of BQK device A roller, penetraction depth also claims insertion depth, when A roller does not contact with the strip or just contacted with the strip and during without interaction force, is with steel side-looking to be straight line between roller B and planisher.Definition A roller has just contacted with the strip and has been penetraction depth 0 point during without interaction force, when roller A moves a distance, d d, thereby make to be with between roller B and planisher steel bend (now between roller A and band steel, there is contact action power) just claim roller A incision or insert band steel, corresponding dd is exactly the penetraction depth of roller A now, as shown in figure 10, blue is roller A and the original state with steel, and black is end-state.

In step 6: the penetraction depth d calculating according to step 5, adjust A roller height adjusting as shown in figure 10, the penetraction depth d calculating according to step 5 increases or reduces A roller and cuts the height dd with steel; Complete the present invention regulates the improvement of cold-strip steel warpage to this.

Iterative computation is a kind of mathematic calculation that solves implicit function.What in step 5, we will be according to actual measurement solves the penetraction depth d of BQK device A roller with steel warpage, but be difficult to obtain penetraction depth d about the function with steel warpage, holding facile is the function about penetraction depth d with steel warpage, therefore needs to solve by the method for iterative computation.

The method of iterative computation is a lot, specific to the present invention, can adopt dichotomy to solve, solution procedure is, first calculate band steel warpage regulation and control amount corresponding to maximum penetraction depth according to the formula of step 5, if actual measurement warpage defect has exceeded this value, illustrate that this warpage has exceeded regulating power scope under present case, cannot regulate.If now warpage is in modification scope, search for best penetraction depth d by alternative manner, concrete search procedure is as follows, when the penetraction depth of the k time circulation is taken as d ^k, eccentricity interval is relatively according to d ^kthe relation with steel warpage and actual measurement warpage of calculating is determined the penetraction depth interval of the k+1 time circulation time.If result of calculation is greater than actual conditions, interval is otherwise interval is the penetraction depth value of corresponding the k+1 time circulation time is when the deviation of certain result of calculation and measured value be less than measured value 1% time, stop calculate.

According to the device that improves of a kind of cold-strip steel warpage of the present invention, it is characterized in that, described smooth unit and BQK device space are 300-1000mm from scope.

According to the device that improves of a kind of cold-strip steel warpage of the present invention, it is characterized in that, described planisher work roll diameter is 300-400mm.

According to the device that improves of a kind of cold-strip steel warpage of the present invention, it is characterized in that, the diameter of described BQK device A roller is 40-100mm.

According to the device that improves of a kind of cold-strip steel warpage of the present invention, it is characterized in that, described BQK device is 300-1000mm to the distance L of planisher.

According to the device that improves of a kind of cold-strip steel warpage of the present invention, it is characterized in that described c ₁constant term interval is 0-1.

According to the device that improves of a kind of cold-strip steel warpage of the present invention, it is characterized in that described k ₄influence coefficient span-20-20.

Core of the present invention is a set of warpage control device that is arranged on planisher outlet, called after BQK device.It is made up of two rollers, as depicted in figs. 1 and 2.Its central roll A can regulate height in vertical direction, and roller B is stationary roll.Specific requirement is as follows:

(1) the roller footpath of roller A and roller B and distance relation meet aligning condition.

(2) the roller A adjustment of height in vertical direction should be able to change planisher working roll and with the rolling cornerite between steel.

(3) according to the difference of the planisher kind of drive, roller A is different with the arrangement of roller B, and in the time that planisher adopts the independent transmission of lower roll, roller A is arranged in band steel downside, and roller B is arranged in band steel upside, and the pivot of roller B is apart from height of rolling line H _bensure that i.e. not influence of rolled line height of roller B, shown in Fig. 2 for the radius of roller B; In the time adopting the independent transmission of top roll, roller A is arranged in band steel upside, and roller B is arranged in band steel downside, and the pivot of roller B is apart from height of rolling line H _bensure that i.e. not influence of rolled line height of roller B, shown in Fig. 3 for the radius of roller B; In the time that planisher adopts upper and lower separate transmission, there is no particular/special requirement.

The range of choice of the diameter D of roller A need to meet following relational expression guarantee band steel plastic deformation occurs when through roller A,

$0.1D_t\≤D\≤0.5\frac{\mathrm{\δE}}{{\mathrm{\σ}}_S}---\left(1\right)$

In formula, δ---band steel minimum thickness;

σ _s---band steel yield limit,

D _t---planisher work roll diameter.

The roll surface length L of roller A _aneed to meet following relational expression,

1.1B _max≤L _A≤1.6B _max (2)

In formula, B _max---band steel Breadth Maximum,

The operation principle of warpage control device BQK device of the present invention:

As described in goal of the invention part, this device object is that aligning is combined with the technical advantage that changes rolling cornerite, realize adjustment to rolling cornerite and to the aligning with steel warpage defect by a covering device simultaneously, on the one hand from changing upper and lower surface rolling (smooth) state---one of main contributor (being also the Main Means of controlling warpage) that warpage produces is started with, and realizes the control to warpage; By aligning rolling rear band steel, further improve the warpage situation with steel on the other hand.

(a) adjust the improvement of rolling cornerite to warpage

In plate strip rolling process, because the lubricating status planisher up-down rollers kind of drive, upper working rolls and lower working rolls diameter, with steel upper and lower surface all exists difference to a certain degree, cause being with steel upper and lower surface as-rolled condition difference, exist extension to a certain degree inhomogeneous with steel through-thickness afterwards thereby cause to roll, in the time that extension difference acquires a certain degree, will produce warpage defect.With steel upper and lower surface as-rolled condition, thickness direction to be extended in order illustrating the impact distributing, to have carried out finite element simulation simulation.

Fig. 4 is that the planisher cornerite of finite element simulation simulation changes the impact on extending with steel upper and lower surface.The variation that therefrom can find out rolling cornerite is linear approximate relationship with band steel upper and lower surface extension difference.For the lower roll transmission planisher of simulating in emulation, under normal circumstances, band steel lower surface elongation is large, the easy C producing upwards sticks up or L sticks up, therefore, and when changing rolling cornerite by this device roller A, can effectively change band steel upper and lower surface extension difference, thereby play the effect of controlling warpage.

Can be similar to and think that the impact that rolling cornerite extends rate variance (overstrain) to upper and lower surface is linear according to the result of calculation of Fig. 4.And can obtain following formula

Δε ₁＝k ₁×a×d-c ₁ (2)

$a=\frac{180}{\mathrm{\πL}}$

In formula, Δ ε---upper and lower surface is extended rate variance change amount;

K ₁---rolling cornerite changes the influence coefficient to warpage, and interval is [0,1];

A---rolling cornerite is adjusted coefficient, 1/m;

The penetraction depth of the device A roller of d---BQK device, m;

L---BQK device is to the distance of planisher, m;

C ₁---constant term, interval is [0,1];

Therefore, the present invention can realize the adjustment to rolling cornerite by the penetraction depth d that adjusts roller A, thereby poor with the extensional of steel upper and lower surface in controlled rolling district.In the time that roller A presses, increase with steel the cornerite to top working roll, thereby increase distortion with steel upper surface, reduce the distortion with steel lower surface, therefore can improve the residual stress with steel inside, play the object of improving warpage.

(b) improvement of aligning process to warpage

The present invention utilizes two rollers of outlet side to form similar straightening device, makes to realize under the effect of smooth tension force (outlet tension force) with steel stretch bending distortion.In the time adjusting roller A height, with steel in this stretch bending deformation process due to the bending stress being superposeed and tensile stress effect, produce plastic elongation.Due to the residual stress existing with steel before access to plant, therefore will reduced to eliminate even completely through BQK device residual stress, thereby played the effect that improves or eliminate warpage.

In the time adopting the planisher of one high driving, will produce corresponding warpage (C sticks up, L sticks up, turn round stick up etc.) to driven roll one side, therefore can on roller A, grinding go out a roll forming, further improve warpage control effect.

Shown in Fig. 5 is after initial warpage defect forms, the variation of the upper and lower surface stress with steel.Because added temperature field is about belt steel thickness direction symmetry.Upper surface with steel is due to shortening, compression chord; Lower surface with steel is owing to spreading, tension stress.

Fig. 5 is the residual stress distribution situation that uses the upper and lower surface of front and back band steel through BQK device.After aligning, comparatively close with the upper and lower surface stress of steel, thus show to be with steel warpage defect to be eliminated significantly.

In order quantitatively to determine that roller A penetraction depth changes the improvement effect with steel warpage.A large amount of operating modes that used FEM model simulation calculation above.On this basis, use the method for regression analysis to be created as mathematical formulae easy to use.

Fig. 6 relation between poor that is certain ideal format band steel through BQK device aligning process central roll A penetraction depth and upper and lower surface residual stress, therefrom can find out, along with the increase of penetraction depth first reduces rear increase, both there is best penetraction depth value in band steel upper and lower surface residual stress poor (band steel warpage).

The method of employing regression analysis just can obtain the mathematic(al) representation of relation between roller A penetraction depth and upper and lower surface residual stress,

Δσ＝k ₂Dd ²-k ₃Dd+c ₂ (3)

In formula, Δ σ---upper and lower surface residual stress is poor;

D---the diameter of BQK device A roller, m;

D---the penetraction depth of BQK device A roller, m;

K ₂, k ₃, c ₂---regression coefficient, span is respectively [0,10], [50,50], [0,500].

The Mathematical representation of the poor Δ ε of upper and lower surface overstrain is as follows,

$\mathrm{\Δ}{\mathrm{\ϵ}}_2\≈\frac{\mathrm{\Δ\σ}}{E}=\frac{k_{2}D{d}^2-k_3\mathrm{Dd}+c_2}{E}---\left(4\right)$

In formula, E---band steel elastic modelling quantity.

(c) the comprehensive improvement of warpage

Adjust the warpage of rolling cornerite and aligning for determining and comprehensively improve effect, the relation of the penetraction depth of the poor variation delta ε of model overstrain and BQK device A roller,

$\mathrm{\Δ\ϵ}=k_1\×a\×d+\frac{k_{2}D{d}^2-k_3\mathrm{Dd}+c_2}{E}-c_1---\left(5\right)$

In addition, can also set up the poor variation delta ε of overstrain and the relational expression of sticking up height change H with steel C according to geometrical relationship,

$\mathrm{\ΔH}=k_4\·{\sin }^2\left(\frac{\mathrm{b\Δ\ϵ}}{2h}\right)\frac{h}{\mathrm{\Δ\ϵ}}---\left(6\right)$

In formula, h---belt steel thickness, m;

K ₄---influence coefficient, span [20,20].

The penetraction depth d that BQK device A roller just can be determined in simultaneous formula (5), (6) with stick up with steel C the relational expression of highly improving Δ H,

$\mathrm{\ΔH}=k_4\·{\sin }^2\left(\frac{b(K_2{d}^2+K_{2}d+C)}{2h}\right)\×\left(\frac{h}{K_1{b}^2+K_{2}d+C}\right)---\left(7\right)$

In formula, $K_1=\frac{k_{2}D}{E};K_2=k_1\×a-\frac{k_{3}D}{E};C=\frac{c_2}{E}-c_1.$

Finally, in order to give full play to the effect of this device, spy provides following control method (dependence diagram is as shown in Figure 7), comprises following execution step:

Step 1, collects the device parameter of smooth unit, mainly determines the distance between smooth unit and BQK device;

Step 2: determine the device parameter of BQK device, mainly determine the roller footpath of A roller;

Step 3: collect the smooth characterisitic parameter with steel, comprising: the smooth Young's modulus with steel, thickness and the width with steel;

Step 4: measure the depth of camber Δ H of smooth outlet with steel;

Step 5: according to formula $\mathrm{\ΔH}=k_4\·{\sin }^2\left(\frac{b(K_2{d}^2+K_{2}d+C)}{2h}\right)\×\left(\frac{h}{K_1{b}^2+K_{2}d+C}\right)$ Iterative computation goes out the penetraction depth d of BQK device A roller;

Step 6: the height of adjusting A roller according to the penetraction depth d calculating.

According to the improvement method of cold-strip steel warpage of the present invention, it is characterized in that, when planisher adopts the independent transmission of lower roll, described warpage control device roller A is arranged in band steel downside, roller B is arranged in band steel upside, and the pivot of roller B ensures the radius for roller B apart from height of rolling line HB.

Thus, not influence of rolled line height of roller B.

According to the improvement method of cold-strip steel warpage of the present invention, it is characterized in that, when planisher adopts the independent transmission of top roll, described warpage control device roller A is arranged in band steel upside, roller B is arranged in band steel downside, and the pivot of roller B ensures the radius for roller B apart from height of rolling line HB.

Thus, not influence of rolled line height of roller B.

The device that improves that the invention provides a kind of cold-strip steel warpage, is characterized in that, in planisher exit, warpage control device is set, and described warpage control device comprises: respectively can regulate in vertical direction roller A highly and stationary roll roller B as up-down rollers.

The range of choice of the diameter D of roller A need to meet following relational expression guarantee band steel plastic deformation occurs when through roller A,

$0.1D_t\≤D\≤0.5\frac{\mathrm{\δE}}{{\mathrm{\σ}}_S}---\left(1\right)$

In formula, δ---band steel minimum thickness;

σ _s---band steel yield limit,

D _t---planisher work roll diameter.

The roll surface length L of roller A _aneed to meet following relational expression,

1.1B _max≤L _A≤1.6B _max (2)

In formula, B _max---band steel Breadth Maximum.

According to protecting the improvement method of bright cold-strip steel warpage and improving device, former produced tin plate C sticks up heavier, and actual measurement warp value is generally within the scope of 35～60mm.After implementing this scheme, ideal format model amount of warpage is less than 20mm.

Brief description of the drawings

Fig. 1 is a kind of anti-device that sticks up of continuous annealing unit.

Warpage control device when Fig. 2 is planisher lower roll transmission of the present invention.

Warpage control device when Fig. 3 is planisher top roll transmission of the present invention.

Fig. 4 is rolling cornerite and the graph of a relation being out of shape with steel upper and lower surface.

Fig. 5 shows residual stress on the thickness direction of use front and back.

Fig. 6 show BQK device roller A penetraction depth and upper and lower surface residual stress poor between relation.

Fig. 7 is control chart.

Fig. 8 is warpage effect comparison figure before and after implementing.

Fig. 9 is control chart.

Figure 10 is roller A penetraction depth schematic diagram.

In figure, 1 sticks up roller for anti-, and 2 be warpage control device, and 3 is rolling cornerite, and 4 be planisher, and 5 is roller A initial position, and dd is roller A penetraction depth, Fig. 2, and lower roll transmission in 10, in Fig. 3, top roll transmission, 6 expression roller A, 7 expression roller B.

Detailed description of the invention

Below, with reference to accompanying drawing, illustrate the present invention.

Embodiment 1

This patent invention connects to move back on planisher at Baosteel 1220 have been carried out implementing to use.It is up-down rollers separate transmission that planisher moves back in 1220 companies, therefore the layout of BQK device is not had to particular/special requirement, therefore adopts the mode shown in Fig. 2 to arrange.Roller A diameter is 80mm.

Taking width as 1000mm, thickness is as the band steel of 0.5mm is example, and the control method of roller A is described.Suppose to detect existence highly for the C of 100mm sticks up after this specification belt steel flating, can reverse determine that the penetraction depth of roller A is about 75mm according to formula (7), according to this penetraction depth pair roller, A regulates, and just can eliminate with the C of steel and stick up, and control block diagram as shown in Figure 9.

According to the present invention, it is as shown in the table, adopt after this technology, 1220 connect move back the smooth rear band steel warpage of smooth unit be improved significantly.

Table 2 ideal format model C sticks up quality inspection and judges

The present invention has that less investment, instant effect, Operation and Maintenance are simple, the feature of successful.Can be further connect to other move back smooth unit, hot tinning (zinc) line is applicable, and to improve each unit warpage control ability, solves its a product quality difficult problem of puzzlement, has important using value and wide application prospect.

Claims (9)

1. the improvement method of a cold-strip steel warpage, it is characterized in that, in planisher exit, warpage control device is set, described warpage control device comprises: can regulate in vertical direction roller A highly and stationary roll roller B as up-down rollers, comprise the steps: respectively

Step 1, collects the device parameter of smooth unit, collects the distance between smooth unit and warpage control device, and smooth unit and warpage control device spacing scope are 30mm-3000mm,

Step 2: collect the device parameter of warpage control device, comprising:

The diameter of collecting A roller, the diameter D scope of roller A is as follows;

$0.1D_t\≤D\≤0.5\frac{\mathrm{\δE}}{{\mathrm{\σ}}_S}---\left(1\right)$

In formula, δ---band steel minimum thickness;

σ _s---band steel yield limit,

D _t---planisher work roll diameter,

E--Young's modulus,

The roll surface length L of roller A _ameet following relational expression:

1.1B _max≤L _A≤1.6B _max (2)

In formula, B _max---band steel Breadth Maximum,

Step 3: collect the smooth characterisitic parameter with steel, described characterisitic parameter comprises: the smooth Young's modulus with steel, thickness and the width with steel; Wherein Young's modulus E is for calculating parameter K ₁;

Step 4: record the depth of camber △ H:0-200mm of smooth outlet with steel;

Step 5: according to formula

$\mathrm{\ΔH}=k_4\·{\sin }^2\left(\frac{b(K_1{d}^2+K_{2}d+C)}{2h}\right)\×\left(\frac{h}{K_1{d}^2+K_{2}d+C}\right)$

In formula, $K_1=\frac{k_{2}D}{E},$

K ₁for rolling cornerite changes the influence coefficient to warpage, value 0-1;

$K_2=k_1\×a-\frac{k_{3}D}{E};C=\frac{c_2}{E}-c_1,$

B---with the width of steel, m;

E---with the Young's modulus of steel, MPa;

D---the diameter of warpage control device A roller, m;

D---the penetraction depth of warpage control device A roller, m;

A---rolling cornerite is adjusted coefficient, 1/m;

H---belt steel thickness, m;

K ₂, k ₃, c ₂---regression coefficient, span is respectively 0-10 ,-50-50,0-500;

L---warpage control device is to the distance of planisher, m;

C ₁---constant term, interval is 0-1;

K ₄---influence coefficient, span-20-20;

Iterative computation goes out the penetraction depth d of warpage control device A roller;

Step 6: the penetraction depth d calculating according to step 5, the height of adjustment A roller.

2. the improvement method of a kind of cold-strip steel warpage as claimed in claim 1, is characterized in that, described smooth unit and warpage control device spacing scope are 300-1000mm.

3. the improvement method of a kind of cold-strip steel warpage as claimed in claim 1, is characterized in that, described planisher work roll diameter is 300-400mm.

4. the improvement method of a kind of cold-strip steel warpage as claimed in claim 1, is characterized in that, the diameter of described warpage control device A roller is 40-100mm.

5. the improvement method of a kind of cold-strip steel warpage claimed in claim 1, is characterized in that, described warpage control device is 300-1000mm to the distance L of planisher.

6. the improvement method of a kind of cold-strip steel warpage as claimed in claim 1, is characterized in that, described k ₄influence coefficient span-20-20.

7. the improvement method of cold-strip steel warpage as claimed in claim 1, it is characterized in that, when planisher adopts the independent transmission of lower roll, described warpage control device roller A is arranged in band steel downside, roller B is arranged in band steel upside, and the pivot of roller B ensures the radius for roller B apart from height of rolling line HB.

8. the improvement method of cold-strip steel warpage as claimed in claim 1, it is characterized in that, when planisher adopts the independent transmission of top roll, described warpage control device roller A is arranged in band steel upside, roller B is arranged in band steel downside, and the pivot of roller B ensures the radius for roller B apart from height of rolling line HB.

9. the control device of a cold-strip steel warpage, described warpage control device is arranged on planisher exit, it is characterized in that, described warpage control device is respectively can regulate in vertical direction roller A highly and stationary roll roller B as up-down rollers, the range of choice of the diameter D of roller A need to meet following relational expression guarantee band steel plastic deformation occurs when through roller A

$0.1D_t\≤D\≤0.5\frac{\mathrm{\δE}}{{\mathrm{\σ}}_S}---\left(1\right)$

In formula, δ---band steel minimum thickness;

σ _s---band steel yield limit,

D _t---planisher work roll diameter,

E--Young's modulus

The roll surface length L of roller A _aneed to meet following relational expression,

1.1B _max≤L _A≤1.6B _max (2)

In formula, B _max---band steel Breadth Maximum.