CN103920719B - The convex degree control method of hot rolled plate shape - Google Patents

Abstract

The invention discloses a kind of convex degree control method of hot rolled plate shape, comprising: step S100, calculate the convexity deviation of mm finishing mill unit outlet output strip in current control period; Step S200, according to the convexity deviation of gained, calculates the first six finishing stand in mm finishing mill unit and must distribute convexity deviation separately; Step S300, calculates the roller adjustment amount of each finishing stand, and adjusts its bending roller force.The convex degree control method of hot rolled plate shape of the present invention, can carry out real-time Dynamic controlling to the convexity of hot-strip, and adjustment is accurate, stable.

Description

The convex degree control method of hot rolled plate shape

Technical field

The hot rolled plate shape that the present invention relates in iron and steel production controls, and more particularly, is a kind of convex degree control method of the hot rolled plate shape for controlling strip profile in hot rolling.

Background technology

Along with the technological progress of steel production enterprise and improving constantly of end user's requirement, to size, the presentation quality proposition high request of Strip.Plate shape is an important quality index of hot-strip, comprises section configuration (Profile) and flatness control (Flatness) two aspects in general.Section configuration, generally by convexity, the isoparametric formulations of wedge shape degree, is again wherein main control parameters with convexity.In the hot strip steel rolling operation of rolling, the actual profile shape of band steel is not often that always there is thick difference to a certain degree in the middle part of it with edge, the difference between this band steel interior thickness and edge thickness is called as strip profile in complete rectangular shape.And glacing flatness generally represents with relative extension difference or chilled box (also known as angularity).Therefore, the main task that hot rolled plate shape controls be exactly realize the convexity of hot-strip and glacing flatness good.

The plate shape Crown control of current domestic iron and steel enterprises hot-strip is mainly to utilize the method such as CVC milling train, PC milling train, positive and negative roller, working roll roll shifting control to realize, and mainly based on the manual intervention bending roller force of operating personnel in real-time plate shape monitoring with adjustment, lack quantitative criteria accurately.

Authorization Notice No. is that the patent of invention of CN1253251C discloses shape wave control methods in a kind of hot-strip, unrestrained profile shape controlling method in mainly adopting, unrestrained PSCU setup control during strip steel head is adopted, wave in dynamic ASC is adopted to control, to solve the bilateral unrestrained defect that hot-strip causes because of cooling to its rear section.

Authorization Notice No. is that the patent of invention of CN100443205C discloses a kind of hot-strip convex degree control method based on smooth change rolling procedure, it adopts and seamlessly transits function structure and adjust each frame depressing force, thus reaches the control to strip profile and glacing flatness.

Summary of the invention

Object of the present invention, be to provide a kind of can to the convex degree control method of the hot rolled plate shape that strip profile in hot rolling controls.

The convex degree control method of hot rolled plate shape of the present invention, for in multiple control cycle, Crown control is carried out to the band steel being carried out finish rolling process by mm finishing mill unit, described mm finishing mill unit comprises seven smart frame F1 ~ F7, band steel passes through mm finishing mill unit entrance successively after these seven finishing stand rollings, exported by mm finishing mill unit and export, the method comprises the following steps:

A, in current control period, detects the actual convexity of the band steel exported from the outlet of this mm finishing mill unit, and according to target convexity, calculates the convexity deviation d in the current rolling cycle _{cm (k)};

B, according to the convexity deviation in current control period, utilizes the respective distribution convexity deviation e of the first six finishing stand F1 ~ F6 in mm finishing mill unit described in following formulae discovery ₁(k) ~ e ₆(k):

$e_i\left(k\right)=\frac{0.8\·d_{\mathrm{cm}}\left(k\right)}{\underset{i=6}{\overset{i}{\mathrm{\Π}}}\mathrm{eata}\left(i\right)},$

Wherein, e _ik () is the distribution convexity deviation of i-th (i=1,2,3,4,5,6) frame in current control period, eata is (i) the convexity coefficient of heredity of the i-th frame;

C, according to the distribution convexity deviation e of the first six finishing stand F1 ~ F6 in described mm finishing mill unit ₁~ e ₆, to this, in the first six finishing stand, the bending roller force of each finishing stand adjusts, the roller adjustment amount Δ F of each finishing stand in this first six finishing stand in current control period _bi(k) be:

${\mathrm{\ΔF}}_{\mathrm{Bi}}\left(k\right)=K_{a2i}[K_{\mathrm{pi}}{e}_i\left(k\right)+K_{\mathrm{Ii}}\underset{j=1}{\overset{k}{\mathrm{\Σ}}}{e}_i\left(j\right)]/K_C,$

Wherein, K _a2ifor crown feedback Controlling model regulation coefficient, Kpi is the crown feedback proportionality coefficient of the i-th frame, K _iibe the crown feedback integral coefficient of the i-th frame, K _cfor bending roller force is to the influence coefficient of convexity.

Preferably, eata(i) drawn by following formulae discovery:

eata[i]＝cetb[i](1.0-zeta[i])（1.0-ε），

Wherein, cetb [i] is adjustment factor, and ε is relative volume under pressure, and zeta [i] is the output layer gone out by neural computing.

The convex degree control method of hot rolled plate shape of the present invention, can carry out real-time Dynamic controlling to the convexity of hot-strip, and adjustment is accurate, stable.

Accompanying drawing explanation

Fig. 1 is the schematic flow sheet of the convex degree control method of hot rolled plate shape of the present invention.

Detailed description of the invention

Below with reference to the accompanying drawings and detailed description of the invention, the process step of the convex degree control method of hot rolled plate shape of the present invention is described in detail.

On the whole, the convex degree control method of hot rolled plate shape of the present invention, in multiple control cycle, carries out Crown control to the band steel being carried out finish rolling process by mm finishing mill unit.Further, mm finishing mill unit comprises seven smart frame F1 ~ F7, and band steel by mm finishing mill unit entrance, is exported by mm finishing mill unit and exports successively after these seven finishing stand rollings.Composition graphs 1, haply, the method comprising the steps of S100-S300, wherein, in the step s 100, calculates the convexity deviation of mm finishing mill unit outlet output strip in current control period; In step s 200, according to the convexity deviation of gained, calculate the first six finishing stand in mm finishing mill unit and must distribute convexity deviation separately; In step S300, calculate the roller adjustment amount of each finishing stand, and its bending roller force is adjusted.Below each step is described in more detail.

step S100.

In step S100, in current control period, the actual convexity of the band steel exported from the outlet of this mm finishing mill unit is detected, and according to target convexity, calculates the convexity deviation d in the current rolling cycle _{cm (k)}.

To the actual convex measuring of output strip, profile gauge can be utilized to complete, then actual convex value and target convexity be compared, the difference of gained is convexity deviation d _{cm (k)}.

step S200.

In step s 200, according to the convexity deviation in current control period, utilize the respective distribution convexity deviation e of the first six finishing stand F1 ~ F6 in mm finishing mill unit described in following formulae discovery ₁(k) ~ e ₆(k):

$e_i\left(k\right)=\frac{0.8\·d_{\mathrm{cm}}\left(k\right)}{\underset{i=6}{\overset{i}{\mathrm{\Π}}}\mathrm{eata}\left(i\right)},$ (formula 1)

In above-mentioned formula 1, e _ik () is the distribution convexity deviation of i-th (i=1,2,3,4,5,6) frame in current control period, eata is (i) the convexity coefficient of heredity of the i-th frame.

More specifically, the convexity coefficient of heredity eata of i-th frame (i) draws by the convexity precomputation model of routine.In an embodiment of the invention, eata (i) draws by following formulae discovery:

Eata [i]=cetb [i] (1.0-zeta [i]) (1.0-ε); (formula 2)

In formula 2, cetb [i] is adjustment factor, and it is the preset value for each frame, and ε is relative volume under pressure (i.e. the ratio of each frame thickness difference and this frame inlet thickness), and zeta [i] is the output layer calculated by the neural network algorithm of routine.More specifically, in neural computing, network is input as strip width, inlet thickness, relatively volume under pressure, work roll diameter, roll-force and distance edge position, by the neural network algorithm of routine, calculates the zeta [i] as output layer.

Of the present invention one preferred embodiment in, the value of cetb [i] is preferably arranged between 0.9 to 1.1, and the number range of the zeta [i] calculated by neural network algorithm is between 0.25-0.5.

step S300.

In step S300, according to the distribution convexity deviation e of the first six finishing stand F1 ~ F6 in mm finishing mill unit ₁~ e ₆to this, in the first six finishing stand, the bending roller force of each finishing stand adjusts, the adjustment of each frame adopts PI to control (i.e. proportional plus integral control) means, particularly, and the roller adjustment amount Δ F of each finishing stand in this first six finishing stand in current control period _bi(k) be:

${\mathrm{\ΔF}}_{\mathrm{Bi}}\left(k\right)=K_{a2i}[K_{\mathrm{pi}}{e}_i\left(k\right)+K_{\mathrm{Ii}}\underset{j=1}{\overset{k}{\mathrm{\Σ}}}{e}_i\left(j\right)]/K_C,$ (formula 3)

Wherein, K _a2ifor crown feedback Controlling model regulation coefficient, Kpi is the crown feedback proportionality coefficient of the i-th frame, K _iibe the crown feedback integral coefficient of the i-th frame, K _cfor bending roller force is to the influence coefficient of convexity.

When calculating the roller adjustment amount Δ F of each finishing stand _biafter (k), work roll bending control system can be utilized, the bending roller force of each finishing stand is adjusted.Roll bending control system can utilize conventional bending roller force control device to realize.Such as, in the existing roll bending control system of one, comprise a hydraulic system, it has Electromagnetic Control and digital closed loop adjuster.Further, this system also comprises the electro-hydraulic valve be arranged on working roll oil steel, and bootable liquid flows into or efflux cylinder pressure.System is according to roller adjustment amount Δ F _bik (), regulates the electric current in control loop, and then by electro-hydraulic valve, the amount of liquid flowing in hydraulic cylinder or flow out in hydraulic control system, thus bending roller force is adjusted.Certainly, easy understand, the adjustment of bending roller force, also can use conventional other means used in industry to carry out.

Easy understand, is utilizing above-mentioned steps to realize in the process of Crown control, and the adjustment amount of each frame bending roller force needs the maximum conditions of consideration equipment.In addition, this flow process normally should work at profile gauge and detect and start after band steel is by signal, and the cycle of whole flow process and profile gauge detect the cycle of convexity signal at about 2 seconds.

In sum, the convex degree control method of hot rolled plate shape of the present invention, can carry out real-time Dynamic controlling to the convexity of hot-strip, and adjustment is accurate, stable.

Claims (2)

1. the convex degree control method of a hot rolled plate shape, for in multiple control cycle, Crown control is carried out to the band steel being carried out finish rolling process by mm finishing mill unit, described mm finishing mill unit comprises seven smart frame F1 ~ F7, band steel passes through mm finishing mill unit entrance successively after these seven finishing stand rollings, exported by mm finishing mill unit and export, it is characterized in that, the method comprises the following steps:

A, in current control period, detects the actual convexity of the band steel exported from the outlet of this mm finishing mill unit, and according to target convexity, calculates the convexity deviation d in the current rolling cycle _{cm (k)};

B, according to the convexity deviation in current control period, utilizes the respective distribution convexity deviation e of the first six finishing stand F1 ~ F6 in mm finishing mill unit described in following formulae discovery ₁(k) ~ e ₆(k):

$e_i\left(k\right)=\frac{0.8\·d_{\mathrm{cm}}\left(k\right)}{\underset{i=6}{\overset{i}{\mathrm{\Π}}}\mathrm{eata}\left(i\right)},$

Wherein, e _ik distribution convexity deviation that () is the i-th frame in current control period, wherein i=1,2,3,4,5,6, eata (i) they are the convexity coefficient of heredity of the i-th frame;

C, according to the distribution convexity deviation e of the first six finishing stand F1 ~ F6 in described mm finishing mill unit ₁~ e ₆, to this, in the first six finishing stand, the bending roller force of each finishing stand adjusts, the roller adjustment amount Δ F of each finishing stand in this first six finishing stand in current control period _bi(k) be:

$\mathrm{\Δ}{F}_{\mathrm{Bi}}\left(k\right)=K_{a2i}[K_{\mathrm{pi}}{e}_i\left(k\right)+K_{\mathrm{Ii}}\underset{j=1}{\overset{k}{\mathrm{\Σ}}}{e}_i\left(j\right)]/K_C,$

Wherein, K _a2ifor crown feedback Controlling model regulation coefficient, Kpi is the crown feedback proportionality coefficient of the i-th frame, K _iibe the crown feedback integral coefficient of the i-th frame, K _cfor bending roller force is to the influence coefficient of convexity.

2. the convex degree control method of hot rolled plate shape according to claim 1, is characterized in that, eata (i) is drawn by following formulae discovery:

eata[i]＝cetb[i](1.0-zeta[i])(1.0-ε)，

Wherein, cetb [i] is adjustment factor, and ε is relative volume under pressure, and zeta [i] is the output layer gone out by neural computing.