CN107321800B

CN107321800B - Belt steel thickness based on dynamic variable specification dynamically adjusts control method online

Info

Publication number: CN107321800B
Application number: CN201710792887.6A
Authority: CN
Inventors: 彭艳; 崔金星; 杨彦博; 刘才溢; 孙建亮
Original assignee: Yanshan University
Current assignee: Yanshan University
Priority date: 2017-09-05
Filing date: 2017-09-05
Publication date: 2018-09-25
Anticipated expiration: 2037-09-05
Also published as: CN107321800A

Abstract

The invention belongs to Ferrous Metallurgy continuous rolling technology fields, and in particular to a kind of belt steel thickness based on dynamic variable specification dynamically adjusts control method online, and rolling, which is become specification process, is divided into two stages：Wedge-shaped changeover portion generates the stage of stage, wedge-shaped changeover portion between rack.It analyzes roll dynamic draught process first for the different stages, generates stage dynamic thickness change procedure in conjunction with the influence of roll dynamic draught process for system stability, and wedge-shaped transition region, refinement changeover portion Controlling model carries out mill speed control.The present invention can realize the stabilization transition of rolling dynamic variable specification process, reduce strip broken belt or piling of steel accident caused by tension is unstable, improve the stability of online dynamic variable specification.

Description

Strip steel thickness online dynamic adjustment control method based on dynamic variable specification

Technical Field

The invention belongs to the technical field of ferrous metallurgy continuous rolling, and particularly relates to a strip steel thickness online dynamic adjustment control method based on dynamic specification change.

Background

With the development of the automation level of the steel technology, the continuous casting and rolling technology has been applied greatly, and in order to realize the effective utilization of the rolling mill, a dynamic Gauge Change (FGC technology for short) is produced. The dynamic specification changing technology is to change the specification of the strip steel in the rolling process, namely, the thickness, the width and the like of two adjacent coils of strip steel are changed by dynamically adjusting parameters such as roll gap, speed, tension and the like under the condition that a continuous rolling unit does not stop, the requirement that the rolling production process needs to be stopped is met, and the dynamic specification changing technology is a key technology for realizing full-continuous rolling. In the dynamic variable-specification rolling process, the thickness of the rolled strip steel is changed on line so as to realize real-time online adjustment of the production specification of the product; on the basis of ensuring the rapid and accurate realization of the specification changing process, the quality of the strip steel is improved as much as possible in the online specification changing process, the influence of the whole process on the rolling stability of the system is small, and the accidents of strip breakage, folding, roller damage and the like caused by instability in the continuous rolling process are avoided, so that the stable transition of the specification changing process is realized.

In addition, in the process of online specification changing, the roll gap and the roll speed need to be adjusted online for multiple times in a short time, and the roll gap is pressed down to form a wedge-shaped area in the process of dynamic specification changing rolling. Therefore, the wedge-shaped area needs to be controlled to ensure that the length of the wedge-shaped area is less than the distance between the two frames so as to realize the production of variable-specification products; the quality of the strip steel is ensured as much as possible on the basis of realizing the accurate change of the rolling specification; and aiming at the reduction relation of the transition section, a reduction control strategy is formulated to ensure that the strip steel realizes stable transition. The existing rolling dynamic specification changing technology mostly focuses on controlling the rolling process of the roller, and researches on a reduction relation model and a reduction control method of a transition section are less.

Disclosure of Invention

In view of the above technical problems, an object of the present invention is to provide a dynamic on-line dynamic strip thickness adjustment and control method based on dynamic specification change, which analyzes the on-line specification change process of the rolling technology, analyzes the roll gap change reduction process in the dynamic specification change process, and establishes a dynamic specification change model in the high-speed rolling state of a hot-rolled strip finishing mill, which can control the quality of the rolled strip, realize the stable transition of the specification change process, and solve the production problem caused by the unstable production in the dynamic specification change rolling production process, especially in the dynamic reduction process.

The technical scheme of the invention is as follows:

a strip steel thickness on-line dynamic adjustment control method based on dynamic specification changing comprises the steps of firstly determining various parameters of a dynamic specification changing area, carrying out roll pressing impact load analysis to adjust the rolling speed, carrying out wedge transition section thickness analysis in the roll dynamic specification changing control process to carry out speed adjustment under the influence of thickness changing, and establishing a rolling speed control model in the roll dynamic pressing process.

Step 1: performing roll reduction impact load analysis and roll speed adjustment, establishing a rolling force model P (delta P0) to delta 1 delta 2R (T) H (T) N (T) b epsilon R/R0 and delta 1 delta 2 with the genetic coefficient delta of the rolling force being 1 according to a model rolling force P0, a genetic coefficient delta, a material-related genetic coefficient delta 1, a frame-related genetic coefficient delta 2, a temperature-opposing force influence coefficient R (T), an influence coefficient H (T) of an outlet thickness to a deformation, an influence coefficient N (T) of a tension to the rolling force, a strip steel inlet thickness b, a relative thickness reduction rate epsilon, a roll radius R and a reference roll radius R0, obtaining N (T) to W0- (gamma 1T1+ gamma 2T2) according to a relative average high-temperature resistance coefficient W0, a front tension T1, a back tension T2, a front tension influence coefficient gamma 1 and a back tension influence coefficient gamma 2, obtaining N (T) as W0-2 gamma T according to the strip steel tension gamma and a preset tension value, obtaining the influence coefficient of tension change caused by impact load as Kp (W0-lambda P1)/(W0-lambda P0) according to the influence coefficient of the rolling force on the tension Kp and the influence factor of the rolling force on the tension lambda, keeping the strip steel constant tension rolling after obtaining the strip steel tension change caused by the rolling force change, adjusting the strip steel rolling speed, and obtaining the adjusted speed as V as Kp.V 0 according to the initial rolling speed V0;

step 2: calculating a dynamic rolling thickness influence coefficient Kd of the roller and adjusting the speed under the influence of thickness variation by analyzing the thickness of the wedge-shaped transition section with the variable specification of the roller, wherein the wedge-shaped transition section enters a rolling area and passes through the thickness Hi-1G 'of the strip steel at the rolling outlet of the i-1 rack at the time stage according to a tension formula, the tension influence coefficient Kdi of the rolling force of the wedge-shaped section dynamic rolling stage of the i-th rack on the tension is high (t)/Hi-1G', the tension in the rolling process is ensured to be constant, and the dynamic rolling speed after the thickness variation adjustment is considered to be V (t) ═ Kd · V0;

and 3, establishing a rolling speed control model of the dynamic rolling process of the roller by using a rolling force tension influence factor α i and a thickness variation tension influence factor beta i based on speed adjustment to obtain the dynamic speed vij (t) of the wedge-shaped transition section, namely α iKp-V + beta iKdv, and α i + beta i-1.

Preferably, the rolling thickness of each stand is transited from Hi to Hi', and the stable transition of the variable specification process is realized through the stable control of the rolling variable specification speed of the dynamic rolling process of the roller.

Preferably, the variable-specification load distribution is divided, according to the initial set value Hi of the strip thickness at the outlet of the rolling schedule before the dynamic variable-specification process of the hot continuous rolling, the stable rolling strip outlet speed set value Vi of the rolling schedule before the dynamic variable-specification process of the hot continuous rolling, the dynamic thickness Hi (t) of the wedge-shaped area of the dynamic variable-specification process of the hot continuous rolling along with the time, the dynamic control value Vi (t) of the rolling speed in the rolling process of the wedge-shaped area of the dynamic variable-specification process of the hot continuous rolling, the initial set value Hi 'of the strip thickness at the outlet of the rolling schedule after the dynamic variable-specification process of the hot continuous rolling and the stable rolling strip outlet speed set value Vi' of the rolling schedule before the dynamic variable-specification process of the hot continuous rolling, the thickness Hi (t) and the control Vi (t) of the rolling speed are dynamically reduced and adjusted by an online roller according to, a smooth transition to the rolling schedule 2(Hi ', Vi') is achieved.

Preferably, based on the dynamic gauge-changing online dynamic strip steel thickness adjustment control method, when the 1 st roll dynamic adjustment is performed, the first machine frame performs roll dynamic pressing, the inlet strip steel speed is VO, the strip steel thickness is H0, and the strip steel thickness is kept constant in the whole dynamic gauge changing process, wherein V0 'is VO, and H0' is H0;

when the jth roller is dynamically adjusted, the thickness specification of the outlet of the rack where the wedge-shaped section is positioned is subjected to transition conversion, in order to ensure that the rolling speed of the strip steel before the rack for dynamically adjusting the roller is not changed, the rolling speed of the strip steel of the rack including the ith rack is adjusted according to the number j of the dynamically changing specification adjustment and the serial number i of the rack,

when i is equal to j, the wedge-shaped section is in the rolling forming stage of the j-th stand, and the calculation formula of the strip steel rolling speed of each stand during the dynamic adjustment of the roll of the i-th stand is as follows

vij(t)＝αiKpi·Vi-1’+βiKdi·Vi-1’；

When i is larger than j, the wedge-shaped section is in the rolling forming stage of the jth stand, and the calculation formula of the rolling speed of the strip steel of each stand during the dynamic adjustment of the roll of the ith stand is

vij(t)＝vi-1,j(t)·(Vi/Vi-1)；

When the jth roller dynamic adjustment is completed, the wedge area is in the stage between the jth and j +1 stands, and the rolling speed of the strip steel of the ith stand is equal to

ViBj＝(Vi-1Bj’·Hi-1’)/Hi’＝Vi’。

Further, the variable gauge load distribution is divided, and the smooth transition conversion to the rolling schedule 2(H1 ', V1', H2 ', V2', H3 ', V3', H4 ', V4', H5 ', V5') is carried out in order of the rheological gauge from the rolling schedule 1(H1, V1; H2, V2; H3, V3; H4, V4; H5, V5) through the control of the thickness and the rolling speed by the on-line rolling dynamic process (H1(t), V1 (t); H2(t), V2 (t); H3(t), V3 (t); H4(t), V4 (t); H5(t), V5(t)),

H1-H5 are initial set values of the thickness of the strip steel at the outlet of the rolling procedure before the dynamic specification changing process of the hot continuous rolling;

V1-V5 show the set values of the speed of the strip steel outlet stably rolled in the previous rolling schedule in the dynamic specification changing process of hot continuous rolling;

h1(t) -h 5(t) represent the dynamic thickness of the wedge-shaped zone of the hot continuous rolling dynamic gauge changing process along with the change of the time;

v1(t) -v 5(t) represent dynamic control values of rolling speed in the wedge rolling process in the dynamic specification changing process of hot continuous rolling;

h1 '-H5' represents the initial set value of the strip steel thickness at the outlet of the rolling schedule after the dynamic specification changing process of the hot continuous rolling;

v1 'V5' shows the exit speed set points of the rolled strip stabilized by the previous rolling schedule of the hot continuous rolling dynamic gauge changing process.

Preferably, the speed control model of the wedge transition forming process stage is

vij(t)＝αiKpi·V+βiKdiV

wherein vij (t) represents the dynamic rolling speed of the strip steel controlled in the wedge-shaped section forming process, α i represents a speed control tension dynamics influence factor, β i represents a speed control tension thickness variation influence factor, α i + β i is equal to 1, Kp represents the influence coefficient of the rolling force on the tension, Kd represents the influence coefficient of the dynamic reduction thickness on the tension, and V represents the rolling speed of the strip steel before the dynamic action of the rolling roll gap.

Preferably, the speed control model of the wedge at the inter-frame stage is

ViBj＝(Vi-1Bj·Hi-1)/Hi

Wherein ViBj represents the speed of the ith rack after the jth adjustment; the speed of the ith-1 rack of Vi-1Bj after the jth adjustment; hi-1 represents the thickness of the strip steel outlet before the specification adjustment of the i-1 th rack; hi represents the strip exit thickness before ith rack gauge adjustment.

The invention relates to a strip steel thickness on-line dynamic adjustment control method based on dynamic specification change, which analyzes the dynamic rolling process of a roller based on the dynamic specification change, solves the related parameters, sequentially adjusts the strip steel outlet speed of each subsequent rack according to the performed rolling load distribution adjustment scheme, and realizes the stable transition of the specification change process, and comprises the following specific steps:

(1) when the transition section reaches the rolling deformation zone of the 1 st rack of the finishing mill group, the rolling thickness of the inlet is H0, the outlet thickness specification is transited from H1 to H1', the time-varying function H1(t) of the wedge-shaped section transition process ensures that the stable transition is realized under the condition that the inlet speeds of the strip steels rolled by the 1 st and the 2 nd racks are respectively V0 and are not changed, V1, V2, V3, V4 and V5 are sequentially adjusted,

calculating Kp1, Kd1 and parameters α 1 and β 1;

the rolling speed of the No. 1 stand is dynamically adjusted into

v11(t)＝α1Kp1·V0+β1Kd1·V0；V1B1＝(V0·H0)/H1’＝V1’；

v21(t)＝v11(t)·(V2/V1)；V2B1＝(V1B1·H1)/H2；

v31(t)＝v21(t)·(V3/V2)；V3B1＝(V2B1·H2)/H3；

v41(t)＝v31(t)·(V4/V3)；V4B1＝(V3B1·H3)/H4；

v51(t)＝v41(t)·(V5/V4)；V5B1＝(V4B1·H4)/H5；

Wherein the thickness of the strip steel at the variable-specification inlet is not a wedge-shaped area; setting the gauge change starting point as the rolling gauge change entrance position, namely Kd1 ═ H1 (t)/H0;

v11(t) represents the rolling speed dynamic control value of the 1 st stand when the 1 st stand is in the rolling forming stage of the wedge section;

V1B1 shows that the 1 st stand completes the specification conversion, the wedge area is in the 1 st and 2 nd stand stages, and the 1 st stand rolling speed changes for the first time;

v21(t) represents the rolling speed dynamic control value of the No. 2 stand during the No. 1 stand rolling forming stage when the No. 1 stand is subjected to specification conversion;

V2B1 shows that the 1 st stand completes the specification conversion, the wedge area is in the 1 st and 2 nd stand stages, and the 2 nd stand rolling speed changes for the first time;

v31(t) represents the rolling speed dynamic control value of the No. 3 stand during the No. 1 stand rolling forming stage when the No. 1 stand is subjected to specification conversion;

V3B1 shows that the 1 st stand completes the specification conversion, the wedge area is in the 1 st and 2 nd stand stages, and the 3 rd stand rolling speed changes for the first time;

v41(t) represents the rolling speed dynamic control value of the 4 th frame during the rolling forming stage of the 1 st frame when the 1 st frame is subjected to specification conversion;

V4B1 shows that the 1 st stand completes the specification conversion, the wedge area is in the 1 st and 2 nd stand stages, and the 4 th stand rolling speed changes for the first time;

v51(t) represents the rolling speed dynamic control value of the 5 th frame during the rolling forming stage of the 1 st frame when the 1 st frame is subjected to specification conversion;

V5B1 shows that the 1 st stand completes the specification conversion, the wedge area is in the 1 st and 2 nd stand stages, and the 5 th stand rolling speed changes for the first time;

(2) when the wedge-shaped section of the 1 st stand reaches the 2 nd stand of the finishing mill group, the outlet thickness specification is transited from H2 to H2 ', the time-varying function H2(t) of the wedge-shaped section in the transition process ensures that the inlet speeds of the strip steels rolled by the 1 st stand and the 2 nd stand are V0 respectively, the stable transition is realized under the condition that the strip steel outlet speed V1' is not changed, and V2, V3, V4 and V5 are sequentially adjusted;

according to the steps 1,2 and 3 in the step 2, calculating Kp2, Kd2 and parameters α 2 and beta 2;

the 2 nd rack rolling speed dynamic adjustment process comprises the following steps:

v22(t)＝α2Kp2·V1’+β2Kd2V1’；V2B2＝(V1’·H1’)/H2’＝V2’；

v32(t)＝v22(t)·(V3B1/V2B1)；V3B2＝(V2B2·H2)/H3；

v42(t)＝v32(t)·(V4B1/V3B1)；V4B2＝(V3B2·H3)/H4；

v52(t)＝v42(t)·(V5B1/V4B1)；V5B2＝(V4B2·H4)/H5；

starting from the No. 2 frame, the specification changing point entering the rolling area is changed into a wedge-shaped section;

v22(t) represents the rolling speed dynamic control value of the 2 nd stand during the rolling forming stage of the 2 nd stand when the 2 nd stand is subjected to specification conversion;

V2B2 shows that the 2 nd stand completes the specification conversion, the wedge area is in the 2 nd and 3 rd stand stage, the 2 nd stand rolling speed changes the value for the second time;

v32(t) represents the rolling speed dynamic control value of the 3 rd stand during the rolling forming stage of the 2 nd stand when the specification of the 2 nd stand is changed;

V3B2 shows that the 2 nd stand completes the specification conversion, the wedge is in the 2 nd and 3 rd stand stages, and the 3 rd stand rolling speed changes for the second time;

v42(t) represents the rolling speed dynamic control value of the 4 th frame during the rolling forming stage of the 2 nd frame when the 2 nd frame is subjected to specification conversion;

V4B2 shows that the 2 nd stand completes the specification conversion, the wedge is in the 2 nd and 3 rd stand stages, and the 4 th stand rolling speed changes for the second time;

v52(t) represents the rolling speed dynamic control value of the 5 th frame during the rolling forming stage of the 2 nd frame when the 2 nd frame is subjected to specification conversion;

V5B2 shows that the 2 nd stand completes the specification conversion, the wedge is in the 2 nd and 3 rd stand stages, and the 5 th stand rolling speed changes for the second time;

(3) when the transition section reaches the 3 rd stand of the finishing mill group for rolling, the outlet thickness specification is transited from H3 to H3 ', the time-varying function H3(t) of the thickness in the transition process of the wedge-shaped section ensures that stable transition is realized under the condition that the inlet speeds of the strip steels rolled by the 1 st, 2 th and 3 rd stands are respectively V0, V1 ' and V2 ', and V3, V4 and V5 are sequentially adjusted;

calculating Kp3, Kd3 and parameters α 3 and β 3;

the rolling speed of the No. 3 frame is dynamically adjusted into

v33(t)＝α3Kp3·V2’+β3Kd3V2’；V3B3＝(V2’H2’)/H3’＝V3’；

v43(t)＝v33(t)·(V4B2/V3B2)；V4B3＝(V3B3·H3)/H4；

v53(t)＝v43(t)·(V5B2/V4B2)；V5B3＝(V4B3·H4)/H5；

Wherein,

v33(t) represents the rolling speed dynamic control value of the 3 rd stand during the rolling forming stage of the 3 rd stand when the 3 rd stand is subjected to specification conversion;

V3B3 shows that the 3 rd stand completes the specification conversion, the wedge is in the 3 rd and 4 th stand stages, and the rolling speed of the 3 rd stand changes for the third time;

v43(t) represents the rolling speed dynamic control value of the 4 th frame during the rolling forming stage of the 3 rd frame when the 3 rd frame is subjected to specification conversion;

V4B3 shows that the 3 rd stand completes the specification conversion, the wedge is in the 3 rd and 4 th stand stages, and the rolling speed of the 4 th stand changes for the third time;

v53(t) represents the rolling speed dynamic control value of the 5 th frame during the rolling forming stage of the 3 rd frame when the 3 rd frame is subjected to specification conversion;

V5B3 shows that the 3 rd stand completes the specification conversion, the wedge is in the 3 rd and 4 th stand stages, and the 5 th stand rolling speed changes for the third time;

(4) when the transition section reaches the rolling deformation zone of the 4 th rack of the finishing mill group, the outlet thickness specification is transited from H4 to H4 ', the time-varying function H4(t) of the thickness of the wedge-shaped section in the transition process is to ensure that the stable transition is realized under the condition that the inlet speeds of the rolled strip steel are unchanged, namely V0, V1', V2 'and V3', and the V4 and V5 are sequentially adjusted;

calculating Kp4, Kd4 and parameters α 4 and β 4;

the 4 th rack rolling speed dynamic adjustment process comprises the following steps:

v44(t)＝α4Kp4·V3’+β4Kd4V3’；V4B4＝(V3’H3’)/H4’＝V4’；

v54(t)＝v44(t)·(V5B3/V4B3)；V5B4＝(V4B4·H4)/H5；

wherein,

v44(t) represents the rolling speed dynamic control value of the 4 th frame during the rolling forming stage of the 4 th frame when the 4 th frame is subjected to specification conversion;

V4B4 shows that the 4 th stand completes the specification conversion, the wedge is in the 4 th and 5 th stand-to-stand stage, and the rolling speed of the 4 th stand changes for the fourth time;

v54(t) represents the rolling speed dynamic control value of the 5 th frame during the rolling forming stage of the 4 th frame when the 4 th frame is subjected to specification conversion;

V5B4 shows that the 4 th stand completes the specification conversion, the wedge is in the 4 th and 5 th stand-to-stand stages, and the 5 th stand rolling speed changes for the fourth time;

(5) when the transition section reaches the 5 th rack of the finishing mill group for rolling, the outlet thickness specification is transited from H5 to H5 ', the time-varying thickness function H5(t) of the wedge-shaped section in the transition process is to ensure that the stable transition is realized under the condition that the inlet speeds of the rolled strip steel are not changed, such as V0, V1 ', V2 ', V3 ' and V4 ', and V5 is adjusted;

calculating Kp5, Kd5 and parameters α 5 and β 5;

the 5 th rack rolling speed dynamic adjustment process comprises the following steps:

v55(t)＝α5Kp5·V4’+β5Kd5·V4’；V5B5＝(V4’·H4’)/H5’＝V5’；

v55(t) represents the rolling speed dynamic control value of the 5 th frame when the 5 th frame is in the rolling forming stage of the wedge section;

V5B5 shows that the 5 th stand completes the specification conversion, and the 5 th stand rolling speed changes 5 times, namely the final steady state rolling value of the specification conversion.

A rolling control method for a dynamic reduction and specification change process is characterized in that the rolling control method for the 1 st machine frame to perform the dynamic reduction and specification change process comprises the following steps,

(1) determining the incoming material information of the variable-specification strip steel, and determining the dynamic rolling reduction and the rolling speed of a roller; (2) determining the position of a variable specification point, and performing a 1 st rack variable specification process; (3) judging whether the wedge-shaped transition section is positioned in the rolling area or not; (4) determining that the wedge-shaped transition section is positioned in a rolling area, calculating the rolling reduction of the dynamic roller, the rolling influence coefficient Kp and the thickness variation influence coefficient Dd, controlling the rolling speed, and entering the step (6); (5) if the wedge-shaped transition section is determined to be positioned outside the rolling area, the wedge-shaped transition section is controlled to flow between the racks according to the volume invariance principle, and then the step (6) is carried out; (6) carrying out speed conversion adjustment on the No. 2, No. 3, No. 4 and No. 5 racks according to an adjustment strategy; (7) judging whether the wedge-shaped transition section is positioned between the No. 1 rack and the No. 2 rack; (8) confirming that the wedge-shaped transition section is positioned between the 1 st rack and the 2 nd rack, and finishing the specification changing process of the 1 st rack; (9) and (4) judging that the wedge-shaped transition section is positioned outside the 1 st machine frame and the 2 nd machine frame, and returning to the step (3).

A rolling control method for a dynamic reduction and specification change process of an ith (i is 2,3, 4, 5) frame comprises the following steps,

(1) determining the dynamic rolling reduction and the rolling speed of the roller according to the thickness change function hi-1(x) of the wedge-shaped transition section; (2) detecting the position of the wedge-shaped transition section, and performing the ith frame roller dynamic pressing process; (3) judging whether the wedge-shaped transition section is positioned in the rolling area or not; (4) determining that the wedge-shaped transition section is positioned in a rolling area, calculating the rolling reduction of the dynamic roller, the rolling influence coefficient Kp and the thickness variation influence coefficient Dd, controlling the rolling speed, and entering the step (6); (5) if the wedge-shaped transition section is determined to be positioned outside the rolling area, the wedge-shaped transition section is controlled to flow between the racks according to the volume invariance principle, and then the step (6) is carried out; (6) carrying out speed conversion adjustment on the No. 2, No. 3, No. 4 and No. 5 racks according to an adjustment strategy; (7) judging whether the wedge-shaped transition section is positioned between the No. 1 rack and the No. 2 rack; (8) confirming that the wedge-shaped transition section is positioned between the 1 st rack and the 2 nd rack, and finishing the specification changing process of the 1 st rack; (9) and (4) judging that the wedge-shaped transition section is positioned outside the 1 st machine frame and the 2 nd machine frame, and returning to the step (3).

The invention has the following beneficial effects:

the dynamic rolling reduction process is analyzed, the dynamic specification changing process is refined and analyzed, the relation between dynamic factors and a controlled object is analyzed, a system control mode for controlling the strip steel in the variable specification rolling and variable thickness rolling process by a system is provided, and support is provided for realizing the system control of a variable specification rolling system;

the influence of the dynamic rolling reduction of the roller in the rolling specification and thickness change process on the system in the specification change process of each rack is reflected to the strip steel rolling outlet speed control of each rack through the influence coefficient of the rolling force on the tension and the strip steel thickness change; aiming at the influence of the change of the rolling reduction load, the rolling speed of the strip steel is controlled, and the influence of the change of the rolling load in the dynamic rolling process of the roller on the stability of the system is compensated; aiming at the analysis in the rolling thickness direction, the implementation of a roller speed control and adjustment strategy is carried out, so that the variable-specification thickness control precision of the roller is improved;

the speed control method for the online variable-specification thickness variation process established by the invention is combined with the online variable-specification automation technology mediation, so that powerful support is provided for improving the FGC dynamic variable-specification thickness precision and the shape quality, improving the stability of the roll dynamic reduction variable-specification process, improving the precision and the production efficiency of products produced by online variable-specification continuous rolling, and reducing the cost of the variable-specification process.

Drawings

FIG. 1 is a schematic diagram illustrating an embodiment of the present invention for analyzing the effect of dynamic roll reduction on the system;

FIG. 2 is a schematic illustration of a stage of the wedge between the frames according to an embodiment of the present invention;

FIG. 3 is a schematic diagram illustrating a roll gap change of a dynamic variable-specification rolling of the 1 st stand according to an embodiment of the present invention;

fig. 4 is a schematic diagram of the dynamic rolling gap change of the ith (i-2, 3,4, 5) stand in the embodiment of the invention;

FIG. 5 is a flowchart illustrating rolling control performed during the dynamic reduction and specification change of the No. 1 rack according to an embodiment of the present invention; and

fig. 6 is a flowchart of rolling control in the dynamic reduction process performed by the i-th (i-2, 3,4, 5) stand according to the embodiment of the present invention.

Detailed Description

Exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers can indicate functionally identical or similar elements. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

FIG. 1 is a schematic illustration of the effect on the system of dynamic roll reduction according to an embodiment of the present invention, wherein roll gap dynamic adjustment is performed in FIG. 1 for a dynamically variable gauge process wherein the controlled reduction speed is u (t) and the strip rolling speed is v (t), the effect of the process on the stability of the rolling system is in the form of forces, e.g., P1 and P2, acting on the rolls at the strip contact surface; FIG. 2 is a schematic view showing a stage state in which a wedge-shaped transition section is located between stands, and FIG. 2 shows that the i-1 th stand has completed a specification-changing state in which the thickness of the strip at the exit is Hi-1', the thickness of the strip entering the i-th stand is still Hi-1, and the thickness of the strip at the exit of the i-th stand is still Hi; fig. 3 is a schematic diagram of the roll gap change of the 1 st stand in the dynamic gauge-changing rolling process according to the embodiment of the invention, in fig. 3, the dynamic adjustment process of the 1 st stand is divided into 3 stages, which are respectively illustrated by three positions D0, D1 and D2, wherein the position D0 is the initial point of the whole gauge-changing process; the position D1 is a roller dynamic pressing process; d2 is that the 1 st rack completes the dynamic specification changing process; fig. 4 is a schematic diagram of a dynamic gauge changing roll gap change of an ith (i-2, 3,4, 5) stand according to an embodiment of the present invention; wherein, at the position behind the 1 st machine frame, all the dynamic specification-changing inlets are wedge-shaped transition sections, the dynamic adjustment process is also divided into three stages which are respectively represented by E0, E1 and E2, wherein E0 is the initial point of the ith machine frame for dynamic roll gap adjustment; e1 is the dynamic rolling process of the roller; e2 completes dynamic specification change for the ith rack.

A strip steel thickness on-line dynamic adjustment control method based on dynamic specification changing comprises the steps of firstly determining various parameters of a dynamic specification changing area, carrying out roll pressing impact load analysis so as to adjust the rolling speed, carrying out wedge transition section thickness analysis in the roll dynamic pressing specification changing control process so as to adjust the speed under the influence of thickness changing, and establishing a rolling speed control model in the roll dynamic pressing process, wherein the specific steps are as follows:

step 1: analyzing the pressing impact load of the roller and adjusting the rolling speed;

when the rolling with the gauge changed is performed under the dynamic rolling of the roll, firstly, the impact load of the dynamic rolling of the roll is analyzed, as shown in fig. 1 and fig. 2, the dynamic rolling impact of the roll and the transient transverse velocity impact are respectively represented as P1 and P2, and P is represented as the resultant force action of P1 and P2 in the figure according to the contact dynamics. Further, a rolling force model of the strip steel hot continuous rolling mill is established, taking the rolling force model of the strip steel hot continuous rolling mill of 2050mm as an example:

P＝δP0＝δ1δ2R(t)H(t)N(T)bεR/R0

wherein P is rolling force; p0 is the model rolling force; δ is a genetic coefficient, δ 1 is a material-related genetic coefficient, δ 2 is a frame-related genetic coefficient, and δ is δ 1 δ 2; r (t) is the temperature counter force influence coefficient; h (t) is the influence coefficient of the outlet thickness on the deformation; n (t) is the influence coefficient of tension on rolling force; b is the thickness of the strip steel inlet; epsilon is relative thickness reduction rate; r is the roller radius; r0 is the reference roll radius. The genetic coefficient delta of the rolling force is 1,

N(t)＝W0-(γ1T1+γ2T2)；

wherein W0 is a relative average high-temperature resistance coefficient, and gamma 1 and gamma 2 are respectively front and rear tension influence coefficients; t1 is front tension and T2 is back tension;

further, N (T) ═ W0-2 γ T;

wherein gamma is the strip steel tension, and T is a preset tension value;

therefore, the influence coefficient of the tension change caused by the impact load on the tension is as follows:

Kp＝(W0-λP1)/(W0-λP0)

wherein Kp is the influence coefficient of the rolling force on the tension; λ is the factor of the influence of the rolling force on the tension (unit: 1/KN).

After the tension change of the strip steel caused by the rolling force change is obtained, the strip steel is kept to be rolled under constant tension, and the rolling speed of the strip steel is adjusted, wherein the adjusted speed is as follows:

V＝Kp·V0

wherein V represents the rolling speed adjusted in consideration of the change in rolling force; v0 represents the initial rolling speed.

Step 2: performing thickness analysis on the wedge-shaped transition section with the variable specification under the rolling reduction and speed adjustment under the influence of thickness variation;

as shown in fig. 3 and 4, after the wedge-shaped transition section enters the rolling zone, the strip thickness hi (t) is influenced by the roll reduction speed u (t), and the influence coefficient of the dynamic reduction thickness of the roll is calculated according to a tension formula and is Kd as shown in the following formula:

Kdi＝hi(t)/Hi-1G’；

wherein Kdi represents the tension influence coefficient of the rolling force in the wedge dynamic rolling stage of the ith stand; Hi-1G' is the thickness of the strip steel at the outlet of the i-1 th stand rolling in the time stage;

therefore, under the condition of ensuring that the tension of the rolling process is not changed, the adjusted dynamic speed is shown as the following formula:

V(t)＝Kd·V0

wherein V (t) represents a rolling speed adjusted in consideration of a change in thickness; v0 represents the initial rolling speed.

And step 3: establishing a rolling speed control model of a roller dynamic pressing process;

the method is characterized in that the rolling speed control model is established by adopting a rolling force tension influence factor α i and a thickness variation tension influence factor β i based on speed adjustment according to the rolling load dynamic change and the thickness reduction change in the stability control of the rolling gauge changing process, wherein α i + β i is 1, and the wedge transition section dynamic speed vij (t) expresses the rolling speed control model by the influence factors of the two factors as follows:

vij(t)＝αiKp·V+βiKdV；

and 4, step 4: and combining the specification changing process, dividing the roll reduction dynamic specification changing process into two conditions that the wedge-shaped transition section is positioned in a rolling area and the wedge-shaped transition section is positioned between the frames, and performing rolling specification changing speed control.

Two rolling schedules are provided in an embodiment of the present invention. Preferably, the thickness of rolling schedule 1 is divided into six sections of 10mm, 8mm, 6.4mm, 5.12mm, 4.10mm and 3.28mm, respectively, with corresponding strip speeds of 1m/s, 1.25m/s, 1.56m/s, 1.95m/s, 2.44m/s and 3.05m/s, respectively, as shown in Table 1.

Preferably, the thickness of the rolling schedule 2 is divided into six sections of 10mm, 7.5mm, 5.63mm, 4.22mm, 3.16mm and 2.41mm, respectively, corresponding to strip speeds of 1m/s, 1.33m/s, 1.78m/s, 2.37m/s, 3.16m/s and 4.21m/s, respectively, as shown in Table 2

Table 1:

item	0	1	2	3	4	5
							Thickness/mm	10	8	6.4	5.12	4.10	3.28
Strip speed/m/s	1	1.25	1.56	1.95	2.44	3.05

Table 2:

item	0	1	2	3	4	5
							Thickness/mm	10	7.5	5.63	4.22	3.16	2.41
Strip speed/m/s	1	1.33	1.78	2.37	3.16	4.21

Wherein, the rolling thickness of each frame is transited from Hi to Hi', and the stable transition of the specification changing process is realized by the stable control of the rolling specification changing speed in the dynamic rolling process of the roller.

And 5: when the rolling regulation process is started, the process is carried out according to a concurrent flow regulation mode, and the strip rolling inlet thickness H0 'is H0, and the speed V0' is V0.

According to the specific embodiment step 1, determining a dynamic parameter Kp1 through a dynamic pressing process;

according to embodiment step 2, the dynamic reduction thickness influence coefficient is determined to be Kd1, and it is specifically noted herein that since H0 ═ H0, Kd0 ═ hi (t)/H0;

according to embodiment step 3, a rolling force tension influencing factor α 1 and a thickness variation tension influencing factor β 1 based on speed adjustment are determined.

When the transition section reaches the rolling deformation zone of the 1 st rack of the finishing mill group, the rolling thickness of the inlet is H0, the outlet thickness specification is transited from H1 to H1', and the time-varying function H1(t) of the thickness in the transition process of the wedge-shaped section ensures that stable transition is realized under the condition that the inlet speeds of the rolled strip steels of the 1 st and 2 th racks are respectively V0 and are not changed, and sequentially adjusting V1, V2, V3, V4 and V5;

calculating Kp1, Kd1 and parameters α 1 and β 1;

the 1 st rack rolling speed dynamic adjustment process comprises the following steps:

v11(t)＝α1Kp1·V0+β1Kd1·V0；V1B1＝(V0·H0)/H1’＝V1’；

v21(t)＝v11(t)·(V2/V1)；V2B1＝(V1B1·H1)/H2；

v31(t)＝v21(t)·(V3/V2)；V3B1＝(V2B1·H2)/H3；

v41(t)＝v31(t)·(V4/V3)；V4B1＝(V3B1·H3)/H4；

v51(t)＝v41(t)·(V5/V4)；V5B1＝(V4B1·H4)/H5；

V5B1 shows that the 1 st stand completed the specification change, the wedge was in the 1 st and 2 nd stand-to-stand stage, and the 5 th stand rolling speed changed for the first time.

The 1 st rack specification-changing speed adjusting process is as follows:

when the 1 st frame changes the specification process, the wedge section is at the 1 st frame rolling formation stage, and the 1 st frame rolling speed dynamic control model shows as:

v11(t)＝α1Kp1·1+β1K1·1

the 1 st stand is changed into specification, the wedge zone is in the 1 st and 2 nd stand stages, and the 1 st stand rolling speed is expressed as:

V1B1＝(V0·H0)/H1’＝V1’＝1.33

when the 1 st frame is subjected to the specification changing process, the wedge area is in the 1 st frame rolling forming stage, and the 2 nd frame rolling speed dynamic control is represented as:

v21(t)＝v11(t)·(V2/V1)＝1.25(α1Kp1·1+β1K1·1)；

the 1 st frame is changed into specification, the wedge zone is in the 1 st and 2 nd frame stage, and the 2 nd frame rolling speed is expressed as:

V2B1＝(1.33·8)/6.4＝1.66；

when the 1 st frame is subjected to the specification changing process, the rolling forming stage of the 1 st frame in the wedge area is performed, and the rolling speed dynamic control of the 3 rd frame is represented as follows:

v31(t)＝v21(t)·(V3/V2)＝1.252(α1Kp1·1+β1K1·1)；

the 1 st stand is changed into specification, the wedge is in the 1 st and 2 nd stand stages, and the 3 rd stand rolling speed is expressed as:

V3B1＝(1.66·6.4)/5.12＝2.08；

when the 1 st frame is subjected to the specification changing process, the rolling forming stage of the 1 st frame in the wedge area is carried out, and the rolling speed dynamic control of the 4 th frame is represented as:

v41(t)＝v31(t)·(V4/V3)＝1.253(α1Kp1·1+β1K1·1)；

the 1 st stand is changed into specification, the wedge is in the 1 st and 2 nd stand stages, and the 4 th stand rolling speed is expressed as:

V41＝(2.08·5.12)/4.10＝2.60；

when the 1 st frame is subjected to the specification changing process, the wedge area is in the 1 st frame rolling forming stage, and the 5 th frame rolling speed dynamic control is represented as:

v51(t)＝v41(t)·(V5/V4)＝1.254(α1Kp1·1+β1K1·1)；

the 1 st frame is changed into specification, the wedge is in the 1 st and 2 nd frame stage, and the 5 th frame rolling speed is expressed as:

V5B1＝(2.60·4.10)/3.28＝3.25；

according to the specific embodiment step 1, determining a dynamic parameter Kp2 through a dynamic pressing process;

according to embodiment step 2, determining the dynamic reduction thickness impact coefficient as Kd 2;

according to embodiment step 3, a rolling force tension influencing factor α 2 and a thickness variation tension influencing factor β 2 based on the speed adjustment are determined.

When the wedge-shaped section of the 1 st stand reaches the 2 nd stand of a finishing mill group and a new wedge-shaped transition region is rolled, the outlet thickness specification is transited from H2 to H2 ', the time-varying function H2(t) of the wedge-shaped section in the transition process ensures that the inlet speeds of the strip steels rolled by the 1 st stand and the 2 nd stand are V0 respectively, and the stable transition is realized under the condition that the strip steel outlet speed V1' is not changed, and V2, V3, V4 and V5 are sequentially adjusted;

calculating Kp2, Kd2 and parameters α 2 and β 2;

v22(t)＝α2Kp2·V1’+β2Kd2V1’；V2B2＝(V1’·H1’)/H2’＝V2’；

v32(t)＝v22(t)·(V3B1/V2B1)；V3B2＝(V2B2·H2)/H3；

v42(t)＝v32(t)·(V4B1/V3B1)；V4B2＝(V3B2·H3)/H4；

v52(t)＝v42(t)·(V5B1/V4B1)；V5B2＝(V4B2·H4)/H5；

V5B2 shows that the 2 nd stand completed the specification change, the wedge was in the 2 nd and 3 rd stand-to-stand stage, and the 5 th stand rolling speed changed value for the second time.

The 2 nd rack specification-changing speed adjusting process is as follows:

when the 2 nd frame carries out the variable specification process, the wedge section is in the 2 nd frame rolling forming stage, and the 2 nd frame rolling speed dynamic control is expressed as:

v22(t)＝α2Kp2·1.33+β2K2·1.33；

the 2 nd stand is changed to specification, the wedge is in the 2 nd and 3 rd stand-to-stand stage, and the 2 nd stand rolling speed is expressed as:

V2B2＝(1.33·7.5)/5.63＝V2’＝1.78；

when the 2 nd frame carries out the variable specification process, the wedge section is in the 2 nd frame rolling forming stage, and the 3 rd frame rolling speed dynamic control is expressed as:

v32(t)＝v22(t)·(V3B1/V2B1)＝1.25(α1Kp1·1.33+β1K1·1.33)；

the 2 nd stand becomes the specification and finishes, the wedge is in the 2 nd, 3 rd inter-stand stage, and the 3 rd stand rolling speed is expressed as:

V3B2＝(1.78·6.4)/5.12＝2.23；

when the 2 nd frame carries out the variable specification process, the wedge section is in the 2 nd frame rolling forming stage, and the rolling speed dynamic control of the 4 th frame is expressed as:

v42(t)＝v32(t)·(V4/V3)＝1.252(α2Kp2·1.33+β2K2·1.33)；

the 2 nd stand is changed to specification, the wedge is in the 2 nd and 3 rd stand-to-stand stage, and the 4 th stand rolling speed is expressed as:

V42＝(2.23·5.12)/4.10＝2.78；

when the 2 nd stand is subjected to the specification changing process, the wedge-shaped section is rolled and formed in the 2 nd stand, and the rolling speed of the 5 th stand is dynamically controlled as follows:

v52(t)＝v42(t)·(V5/V4)＝1.253(α2Kp2·1.33+β2K2·1.33)；

the 2 nd stand is changed to specification, the wedge is in the 2 nd and 3 rd stand-to-stand stage, and the rolling speed of the 5 th stand is expressed as:

V5B2＝(2.75·4.10)/3.28＝3.47；

according to the specific embodiment step 1, determining a dynamic parameter Kp3 through a dynamic pressing process;

according to embodiment step 2, determining the dynamic reduction thickness impact coefficient as Kd 3;

according to embodiment step 3, a rolling force tension influencing factor α 3 and a thickness variation tension influencing factor β 3 based on the speed adjustment are determined.

When the transition section reaches the 3 rd stand of the finishing mill group for rolling, the outlet thickness specification is transited from H3 to H3 ', the time-varying function H3(t) of the thickness in the transition process of the wedge-shaped section ensures that stable transition is realized under the condition that the inlet speeds of the strip steels rolled by the 1 st, 2 th and 3 rd stands are respectively V0, V1 ' and V2 ', and V3, V4 and V5 are sequentially adjusted;

calculating Kp3, Kd3 and parameters α 3 and β 3;

the 3 rd rack rolling speed dynamic adjustment process comprises the following steps:

v33(t)＝α3Kp3·V2’+β3Kd3V2’；V3B3＝(V2’H2’)/H3’＝V3’；

v43(t)＝v33(t)·(V4B2/V3B2)；V4B3＝(V3B3·H3)/H4；

v53(t)＝v43(t)·(V5B2/V4B2)；V5B3＝(V4B3·H4)/H5；

wherein,

V5B3 shows that the 3 rd stand completed the specification change, the wedge was in the 3 rd and 4 th stand-to-stand stage, and the rolling speed of the 5 th stand changed for the third time.

The 3 rd rack specification-changing speed adjusting process is as follows:

when the 3 rd frame is subjected to the specification changing process, the wedge-shaped section is rolled and formed in the 3 rd frame, and the rolling speed of the 3 rd frame is dynamically controlled as follows:

V33(t)＝α3Kp3·1.78+β3K3·1.78；

the 3 rd stand is changed into specification, the wedge is in the 3 rd and 4 th stand-to-stand stages, and the 3 rd stand rolling speed is expressed as:

V3B3＝(1.78·5.63)/4.22＝V3’＝2.37；

when the 3 rd frame is subjected to the specification changing process, the wedge-shaped section is rolled and formed in the 3 rd frame, and the rolling speed of the 4 th frame is dynamically controlled as follows:

v43(t)＝v33(t)·(V4B2/V3B2)＝1.25(α2Kp2·1.78+β2K2·1.78)；

the 3 rd stand is changed into specification, the wedge is in the 3 rd and 4 th stand-to-stand stages, and the 4 th stand rolling speed is expressed as:

V43＝(2.37·5.12)/4.10＝2.96；

when the 3 rd frame is subjected to the specification changing process, the wedge-shaped section is rolled and formed in the 3 rd frame, and the rolling speed of the 5 th frame is dynamically controlled as follows:

v53(t)＝v43(t)·(V5/V4)＝1.252(α3Kp3·1.33+β3K3·1.33)；

the 3 rd stand is changed into specification, the wedge is in the 3 rd and 4 th stand-to-stand stages, and the rolling speed of the 5 th stand is expressed as:

V5B3＝(2.96·4.10)/3.28＝3.70；

according to the specific embodiment step 1, determining a dynamic parameter Kp4 through a dynamic pressing process;

according to embodiment step 2, determining the dynamic reduction thickness impact coefficient as Kd 4;

according to embodiment step 3, a rolling force tension influencing factor α 4 and a thickness variation tension influencing factor β 4 based on the speed adjustment are determined.

When the transition section reaches the 4 th rack of the finishing mill group for rolling, the outlet thickness specification is transited from H4 to H4 ', the time-varying thickness function H4(t) of the wedge-shaped section in the transition process realizes stable transition under the condition that the inlet speeds of the rolled strip steel are unchanged V0, V1', V2 'and V3', and V4 and V5 are sequentially adjusted;

calculating Kp4, Kd4 and parameters α 4 and β 4;

v44(t)＝α4Kp4·V3’+β4Kd4V3’；V4B4＝(V3’H3’)/H4’＝V4’；

v54(t)＝v44(t)·(V5B3/V4B3)；V5B4＝(V4B4·H4)/H5；

wherein,

V5B4 shows that the 4 th stand completed the specification change, the wedge was in the 4 th and 5 th inter-stand stages, and the 5 th stand rolling speed changed by the fourth value.

The 4 th rack specification-changing speed adjusting process is as follows:

when the 4 th rack is subjected to the specification changing process, the wedge-shaped section is rolled and formed in the 4 th rack, and the rolling speed of the 4 th rack is dynamically controlled as follows:

V44(t)＝α4Kp4·2.37+β4K3·2.37；

the 4 th frame is changed into specification, the wedge zone is in the 4 th and 5 th frame-to-frame stage, and the rolling speed of the 4 th frame is expressed as:

V4B4＝(2.37·5.12)/4.10＝V3’＝3.16；

when the 4 th frame is subjected to the specification changing process, the wedge-shaped section is rolled and formed in the 4 th frame, and the rolling speed of the 5 th frame is dynamically controlled as follows:

V54(t)＝v33(t)·(V4B2/V3B2)＝1.25(α4Kp4·2.37+β4K3·2.37)；

the 4 th frame is changed into specification, the wedge zone is in the 4 th and 5 th frame-to-frame stage, and the rolling speed of the 5 th frame is expressed as:

V54＝(2.37·4.10)/3.28＝3.95；

according to the specific embodiment step 1, determining a dynamic parameter Kp5 through a dynamic pressing process;

according to embodiment step 2, determining the dynamic reduction thickness impact coefficient as Kd 5;

according to embodiment step 3, a rolling force tension influencing factor α 5 and a thickness variation tension influencing factor β 5 based on the speed adjustment are determined.

When the transition section reaches the 5 th rack of the finishing mill group for rolling, the outlet thickness specification is transited from H5 to H5 ', the time-varying thickness function H5(t) of the wedge-shaped section in the transition process is to ensure that the stable transition is realized under the condition that the inlet speeds of the rolled strip steel are not changed, such as V0, V1 ', V2 ', V3 ' and V4 ', and V5 is adjusted;

calculating Kp5, Kd5 and parameters α 5 and β 5;

v55(t)＝α5Kp5·V4’+β5Kd5·V4’；V5B5＝(V4’·H4’)/H5’＝V5’；

the influence of the wedge-shaped area on the thickness direction of the strip steel is reduced as much as possible due to the last conversion, so that the reduction rate of the roller needs to be increased as much as possible, and the specification conversion is completed quickly.

V5B5 shows that the 5 th stand completes the specification conversion, the rolling speed of the 5 th stand changes 5 times, namely the final steady rolling value of the specification conversion, and the adjustment process of the 5 th stand speed of the specification conversion is as follows:

when the 5 th frame is subjected to the specification changing process, the wedge-shaped section is rolled and formed in the 5 th frame, and the rolling speed of the 5 th frame is dynamically controlled as follows:

v55(t)＝α5Kp5·3.16+β5Kd5·3.16；

the 5 th stand was finished with the wedge after the 5 th stand, and the 5 th stand rolling speed was expressed as:

V5B5＝(3.16·3.16)/2.37＝V5’＝4.21。

fig. 5 is a rolling control method for performing a dynamic reduction specification change process on the 1 st stand according to the embodiment of the present invention, which includes the following steps:

Fig. 6 shows a rolling control method for performing a dynamic reduction gauge change process on the ith rack in an embodiment of the present invention, which includes the following steps:

Since the invention provides a method for controlling the stability of the variable specification process by adjusting the speed of the variable specification thickness variation process in rolling, it can be understood that the dynamic variable specification method can be modified by those skilled in the art, and the modifications and changes are all due to the protection content of the invention.

Finally, it should be noted that: the above examples are only for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A strip steel thickness on-line dynamic adjustment control method based on dynamic specification changing is characterized in that: which comprises the following steps:

step 1: analyzing the impact load of the roller reduction and adjusting the rolling speed, determining each parameter value of the dynamic variable-specification area,

establishing a rolling force model P (delta P0) delta 1 delta 2R (T) H (T) N (T) b epsilon R/R0, delta 1 delta 2 and a genetic coefficient delta of the rolling force is 1 according to a model rolling force P0, a genetic coefficient delta, a material-related genetic coefficient delta 1, a frame-related genetic coefficient delta 2, a temperature counter force influence coefficient R (T), an influence coefficient H (T) of the outlet thickness on the deformation, an influence coefficient N (T) of the tension on the rolling force, a strip steel inlet thickness b, a relative thickness reduction rate epsilon, a roll radius R and a reference roll radius R0,

according to the relative average high-temperature resistance coefficient W0, the front tension T1, the rear tension T2, the front tension influence coefficient gamma 1 and the rear tension influence coefficient gamma 2, N (T) is W0- (gamma 1T1+ gamma 2T2),

obtaining N (T) W0-2 gamma T according to the strip steel tension gamma and a preset tension value T,

obtaining the influence coefficient of tension change caused by the impact load on the tension according to the influence coefficient Kp of the rolling force on the tension and the influence factor lambda of the rolling force on the tension, wherein the influence coefficient Kp is (W0-lambda P1)/(W0-lambda P0), and P1 is the dynamic rolling impact of the roller;

keeping the strip steel constant tension rolling after the strip steel tension changes due to the rolling force changes, adjusting the strip steel rolling speed, and obtaining the adjusted speed V as Kp-V0 according to the initial rolling speed V0;

step 2: the thickness analysis of the wedge-shaped transition section in the control process of the dynamic rolling reduction specification of the roller is carried out so as to adjust the speed under the influence of thickness variation,

after the wedge-shaped transition section enters a rolling area, the thickness Hi-1G 'of strip steel is rolled at an outlet of an i-1 th stand in a specified time stage, the tension influence coefficient Kdi (t)/Hi-1G' of the rolling force of the i-1 th stand in the wedge-shaped area dynamic rolling stage is ensured to be constant in the rolling process, and the dynamic rolling speed after thickness change adjustment is considered as V (t) ═ Kd.V 0, wherein Hi (t) is the thickness of the strip steel, Kd is the thickness influence coefficient of the dynamic rolling thickness of a roller, and i is the i-th stand;

and step 3: establishing a rolling speed control model of the dynamic rolling process of the roller,

and establishing a rolling speed control model of the dynamic rolling process of the roller by using a rolling force tension influence factor α i and a thickness variation tension influence factor β i based on speed adjustment to obtain the dynamic speed vij (t) ═ α iKp-V + β iKdv and α i + β i ═ 1 of the wedge-shaped transition section, wherein j is the j-th roll gap adjustment.

2. The strip steel thickness on-line dynamic adjustment control method based on dynamic specification change as claimed in claim 1, characterized in that: the rolling thickness of each frame is transited from Hi 'to Hi', and the stable transition of the specification changing process is realized by the stable control of the rolling specification changing speed in the dynamic rolling process of the roller.

3. The strip steel thickness on-line dynamic adjustment control method based on dynamic specification change as claimed in claim 2, characterized in that: dividing variable specification load distribution, according to the initial set value Hi of strip steel thickness at the outlet of the previous rolling procedure in the dynamic specification changing process of hot continuous rolling, the set value Vi of the speed of strip steel outlet stably rolled by the previous rolling procedure in the dynamic specification changing process of hot continuous rolling, the dynamic thickness Hi (t) of wedge zone thickness changing with time in the dynamic specification changing process of hot continuous rolling, the dynamic control value Vi (t) of rolling speed in the wedge zone rolling process in the dynamic specification changing process of hot continuous rolling, the initial set value Hi 'of strip steel thickness at the outlet of the next rolling procedure in the dynamic specification changing process of hot continuous rolling and the set value Vi' of the speed of strip steel outlet stably rolled by the previous rolling procedure in the dynamic specification changing process of hot continuous rolling, carrying out downstream rolling from the rolling procedure 1(Hi, Vi) according to the specification changing sequence, and adjusting the thickness Hi (t) of strip steel and the control Vi, a smooth transition to the rolling schedule 2(Hi ', Vi') is achieved.

4. The strip steel thickness on-line dynamic adjustment control method based on dynamic specification change as claimed in claim 1, characterized in that: the speed control model of the wedge transition section forming process stage is

vij(t)＝αiKpi·V+βiKdiV

5. The strip steel thickness on-line dynamic adjustment control method based on dynamic specification change as claimed in claim 1, characterized in that: the speed control model of the wedge at the stage between the racks is

ViBj＝(Vi-1Bj·Hi-1)/Hi

Wherein ViBj represents the speed of the ith machine frame after the jth adjustment; the speed of the ith-1 rack of Vi-1Bj after the jth adjustment; hi-1 represents the thickness of the strip steel outlet before the specification adjustment of the i-1 th rack; hi represents the strip exit thickness before ith rack gauge adjustment.

6. The strip steel thickness on-line dynamic adjustment control method based on dynamic specification change as claimed in claim 3, characterized in that: when the 1 st roller dynamic adjustment is carried out, the first machine frame carries out roller dynamic pressing, the speed of the inlet strip steel is VO, the thickness of the strip steel is H0, and the strip steel is kept constant in the whole dynamic specification changing process, V0 'is VO, H0' is H0, V0 'is the speed of the inlet strip steel in the dynamic specification changing process, and H0' is the thickness of the inlet strip steel in the dynamic specification changing process;

vij(t)＝αiKpi·Vi-1’+βiKdi·Vi-1’；

vij(t)＝vi-1j(t)·(Vi/Vi-1)；

ViBj＝(Vi-1Bj’·Hi-1’)/Hi’＝Vi’；

Wherein ViBj represents the speed of the ith machine frame after the jth adjustment; vi-1Bj represents the speed of the ith-1 rack after the jth adjustment; hi represents the thickness of the strip steel outlet before the specification adjustment of the ith rack; hi-1 represents the thickness of the strip steel outlet before the specification adjustment of the i-1 th rack; .

7. A rolling control method for a dynamic reduction specification changing process is characterized by comprising the following steps: the rolling control method for the 1 st frame to perform the dynamic reduction specification changing process comprises the following steps,

8. A rolling control method for a dynamic reduction specification changing process is characterized by comprising the following steps: the rolling control method of the i (i is 2,3, 4, 5) th frame in the dynamic reduction gauge-changing process comprises the following steps,