CN113751500A

CN113751500A - Method and device for designing roller shape of middle roller of five-frame six-roller cold continuous rolling unit

Info

Publication number: CN113751500A
Application number: CN202111022225.3A
Authority: CN
Inventors: 陈金山; 张振; 毛向阳; 陈慕珺; 周国平; 王章忠; 卞杰允
Original assignee: Nanjing Institute of Technology
Current assignee: Nanjing Institute of Technology
Priority date: 2021-09-01
Filing date: 2021-09-01
Publication date: 2021-12-07

Abstract

The invention provides a method and a device for designing the shape of a middle roller of a five-rack six-roller cold continuous rolling unit, wherein the method comprises the steps of obtaining roller parameters of the middle roller of the five-rack six-roller cold continuous rolling unit; establishing a space coordinate system by taking the center of a working roll gap of a rolling mill as an original point, taking the axial direction parallel to the working roll as an x axis and the axial direction vertical to the working roll as a z axis; dividing the high-strength steel into a plurality of types according to the yield strength and the width of the strip steel to obtain high-strength steel clusters; establishing a plate-shaped defect evolution model; establishing an optimal transverse displacement regulating matrix of each frame intermediate roller; determining the coordinates of the x axis of each frame middle roller in different transverse moving states in a space coordinate system; calculating parameters of a roller shape curve model of each frame intermediate roller; and establishing a roll-shaped curve model of the middle roll of each frame. By adopting the scheme, the problem that the high-order strip shape defect control effect of the intermediate roller shape design and improvement method based on the macroscopic strip shape defect mechanism in the prior art in the advanced high-strength steel cold rolling process is poor is solved.

Description

Method and device for designing roller shape of middle roller of five-frame six-roller cold continuous rolling unit

Technical Field

The invention belongs to the technical field of metallurgical cold rolling, and particularly relates to a method and a device for designing the shape of a middle roller of a five-rack six-roller cold continuous rolling unit.

Background

The essence of the strip shape is the distribution of residual stress in the strip steel, and as long as the residual stress in the strip steel is not eliminated, the defect of the strip shape inevitably occurs. Cold-rolled steel strip does not allow the presence of "apparent" or "potential" plate defects. Therefore, the strip shape defects can be obtained by using the strip shape detection device according to the distribution rule of the internal stress, and the control mechanism of the rolling mill is guided to carry out quantitative adjustment, so that the qualified strip steel meeting the quality standard can be obtained. The roll shape design is the most direct and effective means for controlling the strip shape. The superior roll shape design can relieve the uneven distribution of contact pressure between the rolls, reduce the uneven wear of the rolls in the rolling process and improve the stress state of the rolling mill, thereby improving the control capability of the rolling mill on the shape of the plate.

At present, many researchers have conducted abundant and valuable work on the design of the roll shape of the work roll through experiments, analyses, numerical simulations, and the like, for example: influence of the shape of a SmartCrown roller of a cold continuous rolling mill on the shape control capability (Beijing university of science and technology 2006, 28, 5 th phase 468 and one side 470) on the wear optimization of the shape of the working roller SmartCrown roller of the UCM unit, improves the control precision of the roller crown, but has no obvious effect on the rolling of high-strength steel; the roll shape curve design and the equivalent convexity discussion of the CVC rolling mill (university of northeast China 2008, 29 vol 10: 1443-; the cold continuous rolling mill same plate difference control technology based on the intermediate roll shape optimization (Bao Steel technology 2015, 2 nd period 59-64) utilizes a finite element method to optimize the intermediate roll end shape of the K-WRS roll shape technology of Kawasaki in Japan, and improves the edge drop control capability of a cold continuous rolling mill set; "an adjustment method of six-roller cold rolling mill and six-roller cold rolling mill" (Chinese patent: CN105032927B) proposes to adopt asymmetric step intermediate roll shape to roll narrow strip steel, to ensure the roll gap rigidity of six-roller cold rolling mill, and adopt variable crown intermediate roll shape of quintic polynomial form to roll wide strip steel, to improve the crown adjusting domain; a cold-rolled intermediate roll (Chinese patent: CN208960621U) adopts a sectional chamfering method to improve the shape control capability of a CVC roll, but the high-order wave shape control capability is weaker.

However, the microscopic basis of the quadridentate high-order strip shape problems such as M-shaped waves, W-shaped waves and the like in the cold continuous rolling process of the advanced high-strength steel is derived from the development and evolution of potential strip shape defects. The intermediate roll shape design and improvement method based on the macroscopic plate shape defect mechanism is not ideal in high-order plate shape defect control effect in the advanced high-strength steel cold rolling process.

Disclosure of Invention

The invention provides a method and a device for designing the shape of a middle roller of a five-frame six-roller cold continuous rolling unit, aiming at the defects in the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the invention provides a method for designing the shape of a middle roller of a five-frame six-roller cold continuous rolling unit, which comprises the following steps:

acquiring roll parameters of a middle roll of a five-frame six-roll cold continuous rolling unit; the parameters of the roller comprise the middle roller mass of each frame, the middle roller labyrinth ring mass, the middle roller material, the middle roller labyrinth material, the middle roller body length, the operation side and driving side roller diameter length of the middle roller, the middle roller diameter, the middle roller operation side and driving side roller neck diameter, the middle roller body hardness, the middle roller neck hardness, the roller matching difference of each frame, the middle roller grinding roller shape error, each middle roller change period and the chrome-plated roller change period;

establishing a space coordinate system by taking the center of a working roll gap of a rolling mill as an original point, taking the axial direction parallel to the working roll as an x axis and the axial direction vertical to the working roll as a z axis;

dividing the high-strength steel into a plurality of types according to the yield strength and the width of the strip steel to obtain high-strength steel clusters;

establishing a plate-shaped defect evolution model according to rolling parameters of middle rollers of each frame and the high-strength steel grade cluster;

establishing an optimal transverse displacement regulating matrix of each frame intermediate roller according to the plate-shaped defect evolution model;

determining the coordinates of the x axis of each frame middle roller in different transverse moving states in a space coordinate system;

calculating parameters of a roll shape curve model of the middle roll of each frame according to the plate shape defect evolution model; the parameters of the middle roller shape curve model of each frame comprise a middle roller shape curve geometric shape angle, a radian rolling shape angle, a geometric amplitude, a first-order inclination coefficient and a second-order inclination coefficient which are defined as corresponding equivalent values;

and establishing a roll shape curve model of each frame middle roll according to the space coordinate system and the parameters of the roll shape curve models of each frame middle roll.

In order to optimize the technical scheme, the specific measures adopted further comprise:

further, establishing a plate shape defect evolution model according to rolling parameters of the middle rolls of the frames and the high-strength steel grade cluster, wherein the establishing comprises the following steps:

establishing a plate shape defect evolution model according to the following formula:

wherein the content of the first and second substances,

when high-strength steel is an Ss steel cluster, the ith frame stress wave induces the evolution of potential plate defects to influence the roll shape correlation coefficient of the intermediate roll, and the dimension is avoided;

when the high-strength steel is a steel cluster Ss, stress waves of all frames induce the evolution of potential plate defects to influence the average roll shape coefficient of the intermediate roll, and the average roll shape coefficient is dimensionless;

when the high-strength steel is a steel cluster Ss, the stress wave induces the critical state geometric characteristic value of the evolution of the potential plate-shaped defect, namely the geometric disturbance quantity, and the dimension is not existed;

when the high-strength steel is a steel cluster Ss, stress waves of all the frames induce the evolution of potential plate defects to influence the mean square value of the roller shape of the intermediate roller, and the mean square value is dimensionless;

when the high-strength steel is a steel grade cluster Ss, the stress wave induces the characteristic coefficient of the critical state physical field of the evolution of the potential plate defect, namely the physical disturbance quantity, and the method is dimensionless.

Further, the establishing of the optimal transverse displacement regulating and controlling matrix of the middle roller of each frame according to the plate shape defect evolution model comprises the following steps:

establishing an optimal transverse displacement regulating and controlling matrix of each frame intermediate roller according to the following formula:

wherein, ω is_IRegulating and controlling a matrix for the optimal transverse displacement; matrix elements

Setting the optimal transverse moving amount of the ith frame intermediate roll when the high-strength steel is a steel cluster Ss;

when i is equal to 1, the optimal transverse moving amount set value of the middle roller of the No. 1 frame of each steel type cluster is as follows:

when i is greater than 1, the optimal transverse moving amount set value of the middle roller of the frame at the rear part of each steel cluster is as follows:

wherein, B_αIs the width coefficient of the cold-rolled steel strip,

lambda is a comprehensive influence factor of the technological parameters in the rolling process,

a reference length is calculated for the intermediate roll body crown.

Further, the calculating the parameters of the roll shape curve model of the middle roll of each frame according to the plate shape defect evolution model comprises:

calculating the equivalent geometric roll form angle of the intermediate roll form curve according to the following formula:

wherein the content of the first and second substances,

when the high-strength steel is a steel grade cluster Ss, the roll-shape curve equivalent geometric roll-shape angle of the intermediate roll is obtained;

reference geometric roller for roller shape curve of intermediate rollerForming corners;

calculating the equivalent radian of the intermediate roll profile curve to form a roll profile angle according to the following formula:

wherein the content of the first and second substances,

making a roll-forming angle by using the equivalent radian of a roll-forming curve of the intermediate roll when the high-strength steel is a steel cluster Ss;

calculating the equivalent geometric amplitude of the roller shape curve of the intermediate roller according to the following formula:

wherein the content of the first and second substances,

when the high-strength steel is a steel grade cluster Ss, the equivalent geometric amplitude of a roll shape curve of the intermediate roll is obtained;

the geometric range of the roller shape curve of the intermediate roller is taken as a reference geometric range;

calculating the equivalent first-order inclination coefficient of the intermediate roll profile according to the following formula:

wherein the content of the first and second substances,

the roll shape curve equivalent first-order inclination coefficient of the intermediate roll is dimensionless when the high-strength steel is a steel cluster Ss;

the roll shape curve of the intermediate roll is a reference first-order inclination coefficient without dimension;

when the high-strength steel is a steel grade cluster Ss, stress waves induce the critical state physical field characteristic coefficients of the evolution of potential plate defects, namely the physical disturbance quantity, and the dimensions are not existed;

calculating the equivalent second-order tilt coefficient of the intermediate roll profile curve according to the following formula:

wherein the content of the first and second substances,

the second-order inclination coefficient of the equivalent of the roller shape curve of the intermediate roller is dimensionless when the high-strength steel is a steel cluster S1;

the high-strength steel is a steel cluster Ss, s>The roll shape curve equivalent second-order inclination coefficient of the intermediate roll is 1 hour, and the two-order inclination coefficient is dimensionless;

the roll shape curve reference second-order inclination coefficient of the intermediate roll is dimensionless;

the stress wave induces the geometrical characteristic value of the critical state of the evolution of the potential plate-shaped defect when the high-strength steel is a steel cluster Ss, namely the geometrical disturbance quantity, and is dimensionless.

Further, the establishing of the roll shape curve model of the middle roll of each frame according to the space coordinate system and the parameters of the roll shape curve model of the middle roll of each frame includes:

establishing a roll shape curve model of each frame intermediate roll according to the following formula:

wherein the content of the first and second substances,

when the high-strength steel is a steel grade cluster Ss under the spatial coordinate, the roll forming value at the x position on the roll forming curve of the middle roll under the ith frame is 1,2, 7; 1,2, ·, 5;

calculating a reference length for the crown of the intermediate roll body;

when the high-strength steel is a steel grade cluster SsSetting the optimal transverse moving amount of the i frame intermediate rolls;

the high-strength steel is a steel cluster Ss, s>The roll shape curve equivalent second-order inclination coefficient of the intermediate roll is 1 hour, and the two-order inclination coefficient is dimensionless; x is the axial coordinate position of any point on the middle roller shape curve relative to the center of the roller body;

establishing a roll diameter model after grinding of the intermediate roll according to the following formula:

wherein the content of the first and second substances,

grinding the roll diameter at the position x on the roll shape curve of the ith frame lower middle roll when the high-strength steel is a steel grade cluster Ss under the space coordinate;

the minimum roll shape value of the roll shape curve of the middle roll under the ith frame when the high-strength steel under the space coordinate is a steel grade cluster Ss; d_I0The original roll diameter before grinding the intermediate roll.

In a second aspect, the present invention provides a device for designing a roll shape of a middle roll of a five-stand six-roll cold continuous rolling mill set, comprising:

the acquisition module is used for acquiring the roller parameters of the middle roller of the five-frame six-roller cold continuous rolling unit; the parameters of the roller comprise the middle roller mass of each frame, the middle roller labyrinth ring mass, the middle roller material, the middle roller labyrinth material, the middle roller body length, the operation side and driving side roller diameter length of the middle roller, the middle roller diameter, the middle roller operation side and driving side roller neck diameter, the middle roller body hardness, the middle roller neck hardness, the roller matching difference of each frame, the middle roller grinding roller shape error, each middle roller change period and the chrome-plated roller change period;

the first establishing module is used for establishing a space coordinate system by taking the center of a working roll gap of a rolling mill as an original point, taking the axial direction parallel to the working roll as an x axis and the axial direction perpendicular to the working roll as a z axis;

the dividing module is used for dividing the high-strength steel into a plurality of types according to the yield strength and the width of the strip steel to obtain high-strength steel clusters;

the second establishing module is used for establishing a plate-shaped defect evolution model according to rolling parameters of middle rollers of all the racks and the high-strength steel grade cluster;

the third establishing module is used for establishing an optimal transverse displacement regulating and controlling matrix of each frame intermediate roller according to the plate-shaped defect evolution model;

the determining module is used for determining the coordinates of the x axis of each rack middle roller in different transverse moving states in a space coordinate system;

the calculation module is used for calculating parameters of the roll shape curve model of the middle roll of each rack according to the shape defect evolution model; the parameters of the middle roller shape curve model of each frame comprise a middle roller shape curve geometric shape angle, a radian rolling shape angle, a geometric amplitude, a first-order inclination coefficient and a second-order inclination coefficient which are defined as corresponding equivalent values;

and the fourth establishing module is used for establishing the roller shape curve model of each frame middle roller according to the space coordinate system and the parameters of the roller shape curve model of each frame middle roller.

Further, the second establishing module comprises:

a first establishing unit for establishing a slab defect evolution model according to the following formula:

wherein the content of the first and second substances,

Further, the third establishing module comprises:

the second establishing unit is used for establishing an optimal transverse displacement regulating and controlling matrix of each frame intermediate roller according to the following formula:

wherein, B_αIs the width coefficient of the cold-rolled steel strip,

a reference length is calculated for the intermediate roll body crown.

Further, the calculation module includes:

a first calculating unit for calculating an intermediate roll profile curve equivalent geometric roll profile angle according to the following formula:

wherein the content of the first and second substances,

a reference geometric roll form angle for a roll form curve of the intermediate roll;

a second calculating unit for calculating the intermediate roll shape curve equivalent radian rolling shape angle according to the following formula:

wherein the content of the first and second substances,

the third calculating unit is used for calculating the equivalent geometric amplitude of the roller shape curve of the intermediate roller according to the following formula:

wherein the content of the first and second substances,

a fourth calculating unit for calculating the intermediate roll profile equivalent first-order roll tilt coefficient according to the following formula:

wherein the content of the first and second substances,

a fifth calculating unit, configured to calculate the second-order roll-shape curve equivalent coefficient of inclination of the intermediate roll according to the following formula:

wherein the content of the first and second substances,

Further, the fourth establishing module comprises:

the third establishing unit is used for establishing a roller-shaped curve model of each frame intermediate roller according to the following formula:

wherein the content of the first and second substances,

calculating a reference length for the crown of the intermediate roll body;

the fourth establishing unit is used for establishing a roll diameter model after the intermediate roll is ground according to the following formula:

wherein the content of the first and second substances,

The invention provides a method and a device for designing the shape of a middle roller of a five-frame six-roller cold continuous rolling unit, wherein the method comprises the steps of obtaining roller parameters of the middle roller of the five-frame six-roller cold continuous rolling unit; the parameters of the roller comprise the middle roller mass of each frame, the middle roller labyrinth ring mass, the middle roller material, the middle roller labyrinth material, the middle roller body length, the operation side and driving side roller diameter length of the middle roller, the middle roller diameter, the middle roller operation side and driving side roller neck diameter, the middle roller body hardness, the middle roller neck hardness, the roller matching difference of each frame, the middle roller grinding roller shape error, each middle roller change period and the chrome-plated roller change period; establishing a space coordinate system by taking the center of a working roll gap of a rolling mill as an original point, taking the axial direction parallel to the working roll as an x axis and the axial direction vertical to the working roll as a z axis; dividing the high-strength steel into a plurality of types according to the yield strength and the width of the strip steel to obtain high-strength steel clusters; establishing a plate-shaped defect evolution model according to rolling parameters of middle rollers of each frame and the high-strength steel grade cluster; establishing an optimal transverse displacement regulating matrix of each frame intermediate roller according to the plate-shaped defect evolution model; determining the coordinates of the x axis of each frame middle roller in different transverse moving states in a space coordinate system; calculating parameters of a roll shape curve model of the middle roll of each frame according to the plate shape defect evolution model; the parameters of the middle roller shape curve model of each frame comprise a middle roller shape curve geometric shape angle, a radian rolling shape angle, a geometric amplitude, a first-order inclination coefficient and a second-order inclination coefficient which are defined as corresponding equivalent values; and establishing a roll shape curve model of each frame middle roll according to the space coordinate system and the parameters of the roll shape curve models of each frame middle roll. By adopting the scheme, the problem that the high-order strip shape defect control effect of the intermediate roller shape design and improvement method based on the macroscopic strip shape defect mechanism in the prior art in the advanced high-strength steel cold rolling process is poor is solved.

Drawings

In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a working flow chart of a method for designing a roll shape of a middle roll of a five-stand six-roll cold continuous rolling mill set according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a roller system structure of the unit according to an embodiment of the present invention;

FIG. 3 is a schematic view of a forward traverse of an intermediate roll provided by an embodiment of the present invention;

FIG. 4 is a schematic illustration of a negative traverse of an intermediate roll provided in an embodiment of the present invention;

FIG. 5 is a graph of the roll profile of the middle roll on five stands rolling DP1200X steel according to an embodiment of the present invention;

FIG. 6 is a graph showing the roll profile of the middle roll on five stands for rolling QP980 steel according to the embodiment of the present invention;

FIG. 7 is a graph showing the roll profile of the middle roll on five stands for rolling W780QX steel according to the embodiment of the present invention;

fig. 8 is a schematic structural diagram of a device for designing the shape of the middle roll of a five-stand six-roll cold continuous rolling mill train according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

As shown in fig. 1, the invention provides a method for designing the shape of a middle roll of a five-stand six-roll cold continuous rolling mill group, which comprises the following steps:

step S101, obtaining roller parameters of a middle roller of a five-frame six-roller cold continuous rolling unit; the parameters of the roller comprise the quality of the middle roller of each frame, the quality of a middle roller labyrinth ring, the quality of the middle roller, the quality of a middle roller labyrinth, the length of a middle roller body, the lengths of the operating side and the driving side of the middle roller, the diameter of the middle roller, the diameters of the operating side and the driving side of the middle roller neck, the hardness of the middle roller body, the hardness of the middle roller neck, the roller matching difference of each frame, the grinding roll shape error of the middle roller, the roll changing period of each middle roller and the roll changing period of the chrome-plated roller.

Step S102, as shown in fig. 2, a spatial coordinate system is established with the center of the roll gap of the work roll of the rolling mill as an origin, the axial direction parallel to the work roll as an x-axis, and the axial direction perpendicular to the work roll as a z-axis.

And S103, dividing the high-strength steel into a plurality of types according to the yield strength and the width of the strip steel to obtain high-strength steel clusters.

In the step, the difference of strain hardening mechanisms of different steel types of the high-strength steel is considered, the strength grade of the steel type is a key factor influencing the rigidity of the roll gap in the cold continuous rolling process, and meanwhile, different specification layers of the steel type are also important factors influencing the plate shape control difficulty of the steel type, particularly in the plate shape control practice of the ultrahigh-strength steel, when the width is large, the influence of the roll gap shape on the comprehensive plate shape quality is larger than the uneven deformation caused by the elastic flattening of the roll, and the adverse effect is more obvious for the high-speed rolling process of a cold continuous rolling unit; however, when wide-specification strip steel is rolled, the uneven deformation caused by the elastic flattening of the rollers is obviously increased along with the increase of the width of the strip steel and is stronger than the influence of the convexity of a roller gap, so the strip shape control capability of a cold continuous rolling unit is continuously enhanced along with the increase of the width of the strip steel, and different intermediate roller shape strategies are adopted for different specifications of high-strength strip steel to realize the effective control of the comprehensive strip shape quality. The invention comprehensively considers the mechanical properties and specification level differences of the steel grades of advanced high-strength steel and combines the control difficulty of high-order wave-shaped defects in the plate shape control process, and the full-series high-strength steel grades of a cold continuous rolling production line are divided into seven categories which are respectively as follows:

considering the difference of strain hardening mechanisms of different steel types of high-strength steel, the strength grade of the steel type is a key factor influencing the rigidity of a roll gap in the cold continuous rolling process, and the different specification layers of the steel type are also important factors influencing the shape control difficulty of the steel type, particularly in the practice of controlling the shape of the ultrahigh-strength steel, when the width B is less than 1450mm, the influence of the shape of the roll gap on the comprehensive shape quality is greater than the uneven deformation caused by the elastic flattening of the roll, and the adverse effect is more obvious for the high-speed rolling process of a continuous rolling unit; however, when rolling strip steel with the width B being more than or equal to 1450mm, the uneven deformation caused by the elastic flattening of the rollers can be obviously increased along with the increase of the width of the strip steel and is stronger than the influence of the convexity of the roller gap, and the rolling of large-scale ultra-wide specification automobile steel products obviously increases the occurrence rate of high-order wave-shaped defects, so that the plate shape control capability of a unit is continuously enhanced along with the increase of the width of the strip steel, and different intermediate roller shape strategies are required to be adopted aiming at different specifications of high-strength strip steel to realize the effective control of the comprehensive plate shape quality. The invention comprehensively considers the mechanical properties and specification level differences of the steel grades of advanced high-strength steel and combines the control difficulty of high-order wave-shaped defects in the plate shape control process, and the full-series high-strength steel grades of a cold continuous rolling production line are divided into seven categories which are respectively as follows:

steel grade cluster S1: sigma is more than 200MPa_sHigh-strength steel with the penetration width of less than or equal to 340 MPa;

steel grade cluster S2: sigma is more than 340MPa_sHigh-strength steel with the pass width of less than or equal to 550 MPa;

steel grade cluster S3: sigma is more than 550MPa_sHigh-strength steel of < 700MPa (pass width);

steel grade cluster S4: sigma is more than or equal to 700MPa_sUltra-high-strength narrow-specification strip steel with the strength of less than 850MPa and B of less than 1600 mm;

steel grade cluster S5: sigma is more than or equal to 700MPa_sThe B is more than 850MPa and more than or equal to 1600 mm;

steel grade cluster S6: sigma_sThe B is less than 1450mm and is more than or equal to 850 MPa;

steel grade cluster S7: sigma_sThe B is not less than 1450mm, and the steel strip has ultrahigh strength and wide specification;

wherein: sigma_sThe yield strength of the high-strength steel finished product strip steel is shown, and the unit is MPa; b represents the width of the high-strength steel finished product strip steel, and the unit is mm.

And step S104, establishing a plate-shaped defect evolution model according to the rolling parameters of the middle roller of each frame and the high-strength steel grade cluster.

In the step, the impedance mismatch effect of the stress wave propagated in the high-strength steel is obviously stronger than that of plain carbon steel, so that larger residual stress can be generated in the high-speed cold deformation process of the high-strength steel, and the stress field of the band steel is obviously influenced. When the dynamic condition and the geometric condition of a local area in the stress field reach the critical state condition of the plate-shaped defect, the development and the evolution of the potential plate-shaped defect are further induced, and finally, the macroscopic local high-order wave-shaped defect is induced. In order to effectively control various high-order plate shape defects in the cold continuous rolling process of high-strength steel, the invention establishes a plate shape defect evolution model aiming at the advanced cold continuous rolling process of high-strength steel:

wherein the content of the first and second substances,

when high-strength steel is an Ss steel cluster, the ith frame stress wave induces the evolution of potential plate defects to influence the roll shape correlation coefficient of the intermediate roll, and the i frame stress wave is mainly influenced by the coupling of the structural characteristics and the geometric characteristics of the intermediate roll system of the continuous rolling mill set, the physical characteristics and the geometric characteristics of strip steel, the parameters of the cold continuous rolling process and other factors in a dimensionless manner;

when the high-strength steel is a steel grade cluster Ss, stress waves of all frames induce the evolution of potential plate shape defects to influence the average coefficient of the roller shape of the intermediate roller, and the physical significance of the stress waves represents the average effect of the stress waves influencing the intermediate roller system in the evolution process of the potential plate shape defects and is dimensionless;

the method has statistical significance, represents the geometrical characteristics of a critical field generated by the plate shape defects microscopically and represents the system effect of the stress wave influencing the whole unit roller system in the plate shape evolution process macroscopically without dimension;

when the high-strength steel is a steel grade cluster Ss, stress waves of all the frames induce the evolution of potential plate shape defects to influence the mean square value of the roller shape of the intermediate roller, and the geometric significance of the mean square value represents the size effect of the stress waves influencing the intermediate roller system in the evolution process of the potential plate shape defects and is dimensionless;

the method has statistical significance for the stress wave induced critical state physical field characteristic coefficient, namely physical disturbance quantity, of the evolution of the potential plate shape defect when the high-strength steel is a steel grade cluster Ss, reflecting the dynamic conditions of the development and the evolution of the potential plate shape defect, microscopically representing the critical field physical characteristics generated by the plate shape defect,the macroscopic representation shows that the stress wave influences the system effect of the whole unit roller system in the process of plate shape evolution, and the system effect is dimensionless.

Establishing a stress wave induced shape evolution key evaluation parameter experimental data curve according to an experimental result, and giving key evaluation parameter experimental data and numerical calculation data of stress wave induced potential shape defect evolution influence factors in a cold continuous rolling process aiming at a typical high-strength steel type sequence of a five-stand cold continuous rolling unit as follows:

steel grade cluster S1: experimental parameter values:

numerical calculation:

steel grade cluster S2: experimental parameter values:

numerical calculation:

steel grade cluster S3: experimental parameter values:

numerical calculation:

steel grade cluster S4: experimental parameter values:

numerical calculation:

steel grade cluster S5: experimental parameter values:

numerical calculation:

steel grade cluster S6: experimental parameter values:

numerical calculation:

steel grade cluster S7: experimental parameter values:

numerical calculation:

and S105, establishing an optimal transverse displacement regulating and controlling matrix of the middle roller of each rack according to the plate-shaped defect evolution model.

In the step, the harmful contact of the roller can be reduced, the harmful bending moment is reduced, the bending and flattening of the roller are relieved by means of the intermediate roller transverse moving technology in the cold continuous rolling process, so that the transverse rigidity of the rolling mill is increased, the strip steel edge drop problem is effectively controlled, a good plate shape control effect is achieved, meanwhile, the contact pressure distribution unevenness between the rollers is reduced, and the abrasion of the intermediate roller is more uniform. The transverse movement of the intermediate roll has a remarkable inhibiting effect on the secondary wave shape of the strip steel, and the secondary plate shape defect can be effectively controlled through the reasonable setting of the transverse movement amount in the actual production process. With the increase of the transverse displacement, the edge thinning amount of the strip steel shows a gradually decreasing trend, and the transverse thickness distribution of the finished strip steel which is approximately rectangular can be obtained by optimally setting the transverse displacement. The factors influencing the optimal transverse displacement of the intermediate roll are numerous, and mainly comprise the influences of the factors such as the strength, the width, the unit rolling force, the roll diameter of the roll, the thermal crown of the roll and the like of the strip steel.

The influence of different incoming steel types on the optimal transverse displacement of the intermediate roll in the cold continuous rolling process is large, and the deformation resistance is increased along with the increase of the strength of the high-strength steel type under the same condition, so that the unit rolling force in the rolling process is increased, and the optimal transverse displacement of the intermediate roll is reduced; the transverse moving amount of the intermediate roll is gradually reduced along with the increase of the diameter of the intermediate roll; the influence of the strip steel width layers on the optimal transverse movement amount of the intermediate roll presents a good linear relation, and the transverse movement amount of the intermediate roll is gradually reduced along with the increase of the strip steel width; the influence of the change of the hot convexity of the roller on the optimal transverse movement amount of the intermediate roller is large, the optimal transverse movement amount of the intermediate roller and the change of the hot convexity of the roller show a basic linear relation, and the transverse movement amount of the intermediate roller is gradually reduced along with the increase of the hot convexity of the roller. In the actual production process, the optimal transverse displacement of the middle roller of the corresponding frame can be calculated and set according to the steel grade cluster layer to which the high-strength steel belongs, so that a good plate shape control effect is achieved.

The transverse movement of the intermediate roll is not only beneficial to eliminating the influence of harmful bending moment of the roll system, but also directly influences the shape of the bearing roll gap. As shown in fig. 3, the intermediate roller is shifted in the forward direction; the positions with larger diameters of the upper roller and the lower roller are gradually close to each other, the bearing roll gaps in the middle area of the strip steel are gradually reduced, the bearing roll gaps in the edge area of the strip steel are gradually increased, the convexity of the strip steel is reduced on the whole, the actual rolling reduction in the middle area of the strip steel is larger, the fiber strips in the middle area are longer after deformation, and the strip steel is easy to have the defect of middle waves; as shown in fig. 4, the intermediate roller is traversed negatively; the smaller positions of the upper and lower roll diameters are gradually close to each other, so that the bearing roll gap of the middle area of the strip steel is gradually increased, the bearing roll gap of the edge area is gradually reduced, the convexity of the strip steel is increased on the whole, the rolling reduction of the edge area of the strip steel is larger than that of the middle area, the fiber strips of the edge area have larger elongation, and the strip steel is easy to have edge wave defects.

Comprehensively considering the influence factors of stress wave induced plate shape evolution of each frame, the control requirements of high-order waves, the transverse movement limit position of the intermediate roll, the strength grade and the width grade of strip steel, the pass deformation, the hot convexity of the roll, the parameters of a roll cooling system and other multi-target constraints, and establishing an optimal transverse movement amount regulation matrix omega of the intermediate roll under different conditions according to the serial number (s is 1,2 … 7) of a steel cluster and the number (i is 1,2 … 5) of a frame_IAnd establishing an optimal transverse displacement regulating and controlling matrix of each frame intermediate roller by taking the steel grade cluster serial number s as a row and taking the frame number i as a column:

wherein, B_αIs the width coefficient of the cold-rolled steel strip,

a reference length is calculated for the intermediate roll body crown.

And step S106, determining the x-axis coordinate of each frame middle roller in different transverse moving states in a space coordinate system.

In this step, according to the geometric relationship of the transverse movement of the intermediate roller in fig. 3 and 4, the transverse coordinate positions of the roller profile curves in different transverse moving states can be further determined as follows:

a. the intermediate roll moves transversely in the positive direction

Roller feeding:

lower roll:

b. negative traverse of intermediate roll

Roller feeding:

lower roll:

step S107, calculating parameters of a roll shape curve model of the middle roll of each frame according to the shape defect evolution model; the parameters of the middle roll shape curve model of each frame comprise a middle roll shape curve geometric roll shape angle, a radian rolling shape angle, a geometric amplitude, a first-order inclination coefficient and a second-order inclination coefficient which are defined as corresponding equivalent values.

In the step, the equivalent geometric roll form angle of the roll form curve of the intermediate roll is calculated according to the following formula:

wherein the content of the first and second substances,

when the high-strength steel is a steel grade cluster Ss, the roll-shape curve equivalent geometric roll-shape angle of the intermediate roll is in degrees;

a reference geometric roll form angle for a roll form curve of the intermediate roll; when the intermediate roll moves forwards, the quadridentate wave-shaped trend is enhanced along with the promotion of the grade of the steel grade cluster Ss, and the quadridentate wave-shaped trend is gradually increasedBig (a)

The value is that the roll shape curve gradually evolves from flat to spiral, the roll shape curve gradient is gradually reduced, the curve distortion degree is increased, the roll shape equivalent convexity value is increased, the quartile roll convexity value is further increased, the convexity difference of the quartile roll is increased, and the control capability of the quartile wave shape is gradually enhanced; similarly, when the middle roller transversely moves in the negative direction, the grade of the steel grade cluster Ss is gradually increased along with the increase of the grade of the steel grade cluster Ss

The value is obtained.

wherein the content of the first and second substances,

when the high-strength steel is a steel grade cluster Ss, a roll angle is made by the equivalent radian of a roll shape curve of the middle roll, and the unit is rad; the design principle of the intermediate roll shape curve equivalent radian rolling shape angle is consistent with the design principle of the equivalent geometric roll shape angle.

wherein the content of the first and second substances,

when the high-strength steel is a steel cluster Ss, the stress wave induces the critical state geometric characteristic value of the evolution of the potential plate-shaped defect, namely the geometric disturbance quantity, and the dimension is not existed; when the intermediate roll moves forwards, the convexity of the strip steel is reduced, and the quadripartion wave-shaped trend is enhanced along with the increase of the grade of the steel grade cluster Ss and is gradually reduced

The roll shape curve is gradually flattened and flattened, the gradient of the roll shape curve is gradually reduced, and the equivalent convexity value of the roll shape is reduced, so that the quarter wave shape is effectively inhibited; when the intermediate roll moves transversely in the negative direction, the convexity of the strip steel tends to increase, and the convexity of the strip steel should be gradually increased along with the increase of the grade of the steel grade cluster Ss

And the roll shape curve gradient is gradually increased, and the equivalent crown value of the roll shape is increased, so that the quartile gradient of the roll shape is continuously increased, the crown control capability of the strip steel is enhanced, and the regulation and control target of high-order wave shape is met.

wherein the content of the first and second substances,

when the high-strength steel is a steel grade cluster Ss, the stress wave induces the characteristic coefficient of the critical state physical field of the evolution of the potential plate defect, namely the physical disturbance quantity, and the method is dimensionless. The design principle of the equivalent first-order inclination coefficient of the intermediate roll shape curve is as follows: when the intermediate roll moves transversely in the positive direction, the quadridentate wave-shaped trend is enhanced along with the promotion of the grade of the steel grade cluster Ss, and the quadridentate wave-shaped trend is gradually increased

Gradually increasing the gradient of a roll shape curve and increasing the equivalent crown value of the roll shape to increase the quadripartion gradient of the roll shape, thereby enhancing the crown control capability of the strip steel and effectively inhibiting high-order wave shape; when the intermediate roll moves transversely in the negative direction, the convexity of the strip steel tends to increase, and the convexity of the strip steel gradually decreases along with the increase of the grade of the steel grade cluster Ss

The roll shape curve gradient is increased continuously, the roll shape quartile gradient is increased, and the roll shape quartile gradient is beneficial to strengthening the regulation and control of high-order wave shape.

wherein the content of the first and second substances,

the stress wave induces the geometrical characteristic value of the critical state of the evolution of the potential plate-shaped defect when the high-strength steel is a steel cluster Ss, namely the geometrical disturbance quantity, and is dimensionless. The design principle of the intermediate roll shape curve equivalent second-order inclination coefficient is as follows: when the intermediate roll moves forwards, the high-order wave trend is enhanced along with the increase of the grade of the steel grade cluster Ss, and the high-order wave trend is gradually reduced

The value is that the shape of the roll shape curve evolves from a power curve shape to a spiral shape gradually, the power function characteristic of the curve is weakened, the bending degree of the roll shape curve is gradually reduced, the gradient of the curve is reduced, the distortion degree of the curve is increased, the equivalent convexity value of the roll shape is reduced, the convexity value of a quartile roll is increased, and the convexity difference of the quartile roll is increased, so that the control capability of high-order wave shape is gradually enhanced; on the contrary, when the middle roller transversely moves in the negative direction, the grade of the steel grade cluster Ss is gradually increased along with the increase of the grade of the steel grade cluster Ss

The value is obtained.

And S108, establishing a roll shape curve model of each frame intermediate roll according to the space coordinate system and the parameters of the roll shape curve model of each frame intermediate roll.

In the step, a roll-shaped curve model of the middle roll of each frame is established according to the following formula:

wherein the content of the first and second substances,

when the high-strength steel is a steel grade cluster Ss under the spatial coordinate, the roll forming value s at the x position on the roll forming curve of the middle roll under the ith frame is 1,2, 7; 1,2, ·, 5;

calculating a reference length for the crown of the intermediate roll body;

wherein the content of the first and second substances,

is high strength under space coordinateWhen the steel is a steel grade cluster Ss, grinding the lower middle roller of the ith rack and then grinding the roller diameter at the x position on the roller shape curve;

the minimum roll shape value of the roll shape curve of the middle roll under the ith frame when the high-strength steel under the space coordinate is a steel grade cluster Ss; d_I0The original roll diameter (namely the flat roll diameter) before grinding the intermediate roll is measured in mm, and the roll diameter D_I0The roll diameter value is increased along with the improvement of the strength of the steel grade according to the strength grade of the rolled steel grade.

As shown in fig. 8, the present invention also provides a device for designing the shape of the middle roll of a five-stand six-roll cold continuous rolling mill, comprising:

the acquisition module 10 is used for acquiring roll parameters of a middle roll of a five-stand six-roll cold continuous rolling unit; the parameters of the roller comprise the middle roller mass of each frame, the middle roller labyrinth ring mass, the middle roller material, the middle roller labyrinth material, the middle roller body length, the operation side and driving side roller diameter length of the middle roller, the middle roller diameter, the middle roller operation side and driving side roller neck diameter, the middle roller body hardness, the middle roller neck hardness, the roller matching difference of each frame, the middle roller grinding roller shape error, each middle roller change period and the chrome-plated roller change period;

the first establishing module 20 is used for establishing a space coordinate system by taking the center of a roll gap of a working roll of the rolling mill as an original point, taking the axial direction parallel to the working roll as an x axis and the axial direction perpendicular to the working roll as a z axis;

the dividing module 30 is used for dividing the high-strength steel into a plurality of types according to the yield strength and the width of the strip steel to obtain high-strength steel clusters;

the second establishing module 40 is used for establishing a plate-shaped defect evolution model according to the rolling parameters of the middle rollers of the frames and the high-strength steel grade cluster;

the third establishing module 50 is used for establishing an optimal transverse displacement regulating and controlling matrix of each frame intermediate roller according to the plate-shaped defect evolution model;

a determining module 60, configured to determine, in a spatial coordinate system, coordinates of an x-axis of each of the frame intermediate rollers in different lateral moving states;

the calculation module 70 is used for calculating parameters of the roll shape curve model of the middle roll of each rack according to the plate shape defect evolution model; the parameters of the middle roller shape curve model of each frame comprise a middle roller shape curve geometric shape angle, a radian rolling shape angle, a geometric amplitude, a first-order inclination coefficient and a second-order inclination coefficient which are defined as corresponding equivalent values;

and a fourth establishing module 80, configured to establish a roll profile curve model of each frame intermediate roll according to the spatial coordinate system and parameters of the roll profile curve model of each frame intermediate roll.

Optionally, the second establishing module includes:

wherein the content of the first and second substances,

Optionally, the third establishing module includes:

wherein, B_αIs the width coefficient of the cold-rolled steel strip,

a reference length is calculated for the intermediate roll body crown.

Optionally, the calculation module includes:

wherein the content of the first and second substances,

wherein the content of the first and second substances,

wherein the content of the first and second substances,

wherein the content of the first and second substances,

wherein the content of the first and second substances,

Optionally, the fourth establishing module includes:

wherein the content of the first and second substances,

calculating a reference length for the crown of the intermediate roll body;

wherein the content of the first and second substances,

The same and similar parts in the various embodiments in this specification may be referred to each other. In particular, as for the apparatus embodiment, since it is substantially similar to the method embodiment, the description is simple, and the relevant points can be referred to the description in the method embodiment.

In order to make the scheme of the application clearer, specific examples are further disclosed in the embodiment of the application.

Example 1

The method is characterized in that a 1740mm UCM five-rack cold continuous rolling unit is taken as an example, the type of a rolling mill is six rolls, the space between the racks is 5500mm, and the maximum rolling force of the rolling mill is 35000kN, a plate shape control mechanism of the unit comprises a working roll bending roll (positive bending, negative bending, and single-side roll bending force of 400-600 kN), a middle roll bending roll (positive bending, negative bending, and single-side roll bending force of 490-700 kN), a middle roll transverse movement (transverse movement amount of-165 mm) and a plate shape control fine cooling system, the pressure control response time of the bending roll system is less than or equal to 130ms, the bending roll force control precision is less than +/-1.0%, and the position control precision of the roll transverse movement system is less than or equal to +/-1.0 mm.

The main roll parameters of the intermediate roll for high-strength steel are as follows: the total weight of the intermediate roll is 5542.3kg, the material of the intermediate roll is forged semi-high-speed Cr steel (the chemical components of the steel of the intermediate roll are shown in the table 1), the mass is 5501.9kg, the material of the labyrinth ring of the intermediate roll is 42CrMo4+ QT, and the mass is 40.2 kg; the length of the middle roll body of the middle roll of the No. 1 to No. 5 frames is 1990.0mm, and the length of the roll neck on the operation side and the driving side is 200.0 mm; middle roller of #1 to #5 machine frameRoller diameter of

Diameter of operation side and driving side roll neck

The hardness of the middle roll body of the middle roll of the No. 1 frame and the No. 2 frame is 80-83 HSD, the hardness of the middle roll body of the middle roll of the No. 3 frame to the No. 5 frame is 77-80 HSD, the hardness of the roll neck is 40-45 HSD, and the hardness uniformity is +/-1.5 HSD; the roller matching difference of the No. 1 to No. 5 frames is less than or equal to 0.05 mm; the error of the grinding roll shape of the intermediate roll is less than or equal to 0.006 mm; the roller changing period of the middle roller of the #1 machine frame is 430X (1 +/-10%) km, the roller changing period of the middle roller of the #2 machine frame is 450X (1 +/-10%) km, the roller changing period of the middle roller of the #3 machine frame is 570X (1 +/-10%) km, the roller changing period of the middle roller of the #4 machine frame is 760X (1 +/-10%) km, the roller changing period of the middle roller of the #5 machine frame is 730X (1 +/-10%) km, and if the middle roller adopts a chrome-plated roller, the roller changing period of each machine frame is 1.52 to 1.95 times that of a conventional roller.

Table 1 half high speed steel for middle roll chemical composition (wt.%)

Chemical elements	C	Cr	Mo	P	Si
						Content (wt.)	0.51～0.60	5.45～6.15	1.02～1.05	0.009～0.012	0.92～1.02
Chemical elements	V	Mn	Ni	S
						Content (wt.)	0.25～0.32	0.32～0.37	0.35～0.42	≤0.002

Roll system cooling system: a. the #1 to #4 stand roll cooling devices are respectively located at the entrance side and the exit side of the work rolls, and at the entrance side of the intermediate rolls. The working roll nozzle group is used for roll gap lubrication, working roll cooling and cleaning and strip steel surface cleaning, the middle roll nozzle group is used for roll gap lubrication between the middle roll and the supporting roll and surface cleaning of the middle roll and the supporting roll, and the nozzle groups are arranged along the width direction of the strip steel at a distance of 125 mm. b. And the #5 stand roller fine cooling device is positioned on the inlet side of the working roller and the intermediate roller. The work roll nozzle group is used for roll gap lubrication, the fine cooling and cleaning of multiple regions of the work roll and the surface cleaning of strip steel, the middle roll nozzle group serves for roll gap lubrication between the middle roll and the supporting roll and the fine cooling and roller cleaning of the multiple regions of the middle roll, the nozzle group is arranged along the width direction of the strip steel, the cooling region interval is 62.5mm, the lubricating region interval is 125mm, and the fine cooling region interval is 120 mm. c. The cooling device directly implemented between the racks is used for directly spraying emulsion on the surface of strip steel before the strip steel enters a roll gap when the advanced high-strength steel is rolled, so that the friction environment of the roll gap is improved, the rolling force is reduced, the lubricating condition is improved, the aim is to obtain the elastic flattening amount of the roll within a reasonable range, and the wave shape control of the strip steel is facilitated.

The ultra-high strength dual-phase steel DP1200X steel grade (the yield strength is 900MPa and is less than or equal to sigma)_sLess than or equal to 1100MPa and tensile strength sigma_bNot less than 1200MPa), the chemical components of the steel are as follows, see Table 2:

TABLE 2 DP1200X chemical composition (wt.%) of high strength steel

Chemical elements	C	Cr	Al	Mo	Ti	Mn	Si	Ni
									Content (wt.)	0.115	0.54	0.038	0.21	0.116	2.38	0.57	0.015
Chemical elements	P	Cu	Sn	V	Nb	B	S
									Content (wt.)	0.016	0.02	0.001	0.006	0.001	0.001	≤0.001

The thickness of the steel coil is 2.959mm, the width is 1184.0mm, the comprehensive plate shape value is 26.16IU, the thickness of the finished product strip steel is 1.408mm, and the high-strength steel is obtained by the classification: the steel grade belongs to a steel grade cluster S6 (sigma)_sNot less than 850MPa and B less than 1450 mm).

(1) The main technological parameters of the cold continuous rolling process are set as follows:

considering the coil switching during the continuous rolling process, which is a non-start coil, the rolling speed setting calculation is completed by using the rolling schedule, see table 3.

The unit tension is set as: an inlet tension of 249.2kN for the #1 rack, an additional tension of 70.0kN, an outlet tension of 466.5kN for the #1 rack, an additional tension of 153.0kN, an outlet tension of 433.6kN for the #2 rack, an additional tension of 180.0kN, an outlet tension of 441.4kN for the #3 rack, an additional tension of 222.0kN, an outlet tension of 318.0kN for the #4 rack, an additional tension of 192.0kN, an outlet tension of 49.2kN for the #5 rack, and an additional tension of 30.0 kN.

The main process parameters of the unit are set as follows, see table 3:

TABLE 3 DP1200X Main Process parameters of Steel Cold continuous Rolling Process

Rack numbering	#	1	#2	#3	#4	#5
							Rolling speed [ m/min ]]	373.0	484.0	545.0	608.0	610.0
Outlet thickness [ mm ]]	2.542	2.056	1.671	1.409	1.408
						Pass reduction [% ]]	15.0	19.3	18.7	15.7	0.1
Roll gap [ mm ]]	0.023	-1.151	-1.050	-1.145	2.306
						Rolling force [ MN]	24.37	23.97	23.95	25.36	5.93
Deviation in Rolling force (DS-OS) [ MN]	-0.11	-0.08	0.07	-0.02	0.31
						Roll inclination [ mm ]]	0.226	0.245	-0.098	-0.042	-0.62
Work roll bending force kN]	1870	2296	2305	2010	2400
						Intermediate roll bending force kN]	2513	2643	2709	1679	2799
Electric machine torque kN m]	98.4	167.0	136.7	116.7	64.2
						Pre-slippery [% ]]	3.12	0.63	1.83	1.69	-0.63
Current load distribution of rolling mill [% ]]	13.0	23.5	25.0	32.0	14.5

Note: and (2) DS: rolling mill drive side parameters, OS: rolling mill operating side parameters; current load distribution: and calculating according to the output power of each rack motor, wherein the value range is (0-100%).

(2) The optimum lateral shift amount setting calculation of the intermediate roller is as follows:

in this embodiment, the key evaluation parameter of the mechanism for influencing the evolution of the stress wave induced potential slab defect in the cold continuous rolling process should be a value corresponding to the steel type cluster S6, and the roll shape correlation coefficients of the intermediate roll for influencing the evolution of the stress wave induced potential slab defect of each stand are obtained as follows:

the average coefficient of the intermediate roll shape influenced by the evolution of the potential plate shape defects induced by the stress waves of each frame is as follows:

the critical state geometric characteristic value of the stress wave induced potential plate shape defect evolution is as follows:

the mean square value of the roll shape of the intermediate roll, which is influenced by the evolution of the potential plate shape defects induced by the stress waves of each frame, is as follows:

the critical state physical field characteristic coefficient of the stress wave induced potential slab defect evolution is as follows:

according to the optimal transverse displacement regulating matrix rule of the intermediate roll, the optimal transverse displacement set values of the intermediate rolls of different frames can be calculated, and the specific process is as follows:

firstly, calculating the optimal transverse moving amount set value of the middle roller of the #1 machine frame of the steel grade cluster S6 as follows:

because, the intermediate roller reference traverse amount:

therefore, the first and second electrodes are formed on the substrate,

namely, the middle roller of the #1 machine frame moves forwards;

then, the optimal transverse displacement setting value of the middle rollers of the #2 to #5 frames of the steel grade cluster S6 can be calculated as follows:

the width coefficient of the cold-rolled strip steel is as follows:

the comprehensive influence factors of the technological parameters in the rolling process are as follows:

the optimum lateral movement amount setting values of the intermediate rolls of the #2 to #5 frames are calculated as follows:

namely, the middle roller of the #2 frame transversely moves in the negative direction;

namely, the middle roller of the #3 frame transversely moves in the negative direction;

namely, the middle roller of the #4 machine frame transversely moves in the negative direction;

namely, the middle roller of the #5 frame transversely moves in the negative direction;

(3) roll profile lateral coordinate position determination

Rack # 1:

and (3) upper intermediate roll:

a lower intermediate roll:

rack # 2:

and (3) upper intermediate roll:

a lower intermediate roll:

rack # 3:

and (3) upper intermediate roll:

a lower intermediate roll:

rack # 4:

and (3) upper intermediate roll:

a lower intermediate roll:

frame # 5:

and (3) upper intermediate roll:

a lower intermediate roll:

(4) the parameters of the intermediate roll profile model are calculated as follows:

in this embodiment, the stress wave influencing factors are introduced into the model parameters such as the intermediate roll shape curve geometric extent, the geometric roll shape angle, the radian rolling shape angle, the first-order tilt coefficient, the second-order tilt coefficient, and the like, and further, the parameters such as the intermediate roll shape curve equivalent geometric extent, the intermediate roll shape curve equivalent geometric roll shape angle, the intermediate roll shape curve equivalent radian rolling shape angle, the intermediate roll shape curve equivalent first-order tilt coefficient, the intermediate roll shape curve equivalent second-order tilt coefficient, and the like can be calculated, and the specific process is as follows:

a. the equivalent geometric amplitude of the roller-shaped curve of the intermediate roller is as follows:

as described above, the #1 frame intermediate roller is forwardly traversed; taking the reference geometric amplitude of the roller shape curve of the intermediate roller:

therefore, the first and second electrodes are formed on the substrate,

the middle rollers of the #2 to #5 frames transversely move in the negative direction; therefore, the first and second electrodes are formed on the substrate,

b. the intermediate roll profile curve equivalent geometric roll profile angle is:

because, the intermediate roll profile reference geometric roll profile angle takes:

therefore, the first and second electrodes are formed on the substrate,

c. the roll forming angle of the intermediate roll is made by the equivalent radian of the roll forming curve of the intermediate roll:

d. the equivalent first-order inclination coefficient of the intermediate roll shape curve is as follows:

the middle roller of the No. 1 frame is positively transversely moved; taking a first-order inclination coefficient of a middle roller profile reference:

therefore, the first and second electrodes are formed on the substrate,

the middle rollers of the #2 to #5 frames transversely move in the negative direction;

therefore, the first and second electrodes are formed on the substrate,

e. the equivalent second-order inclination coefficient of the intermediate roll shape curve is as follows:

the middle roller of the No. 1 frame is positively transversely moved; taking the second-order inclination coefficient of the roller profile curve reference of the intermediate roller:

therefore, the second-order roll-shape curve equivalent second-order tilt coefficient of the middle roll of the steel grade cluster S1 is as follows:

according to the above, the second-order tilt coefficients of the intermediate roll shape curve equivalent of the steel grade clusters S2-S6 can be calculated in sequence as follows:

the second-order tilt coefficients of the intermediate roll shape curve equivalent of the steel grade clusters S2-S6 can be calculated in sequence as follows:

(5) intermediate roll shape curve model expression form

In summary, based on the stress wave induced plate shape evolution influence mechanism, the optimal intermediate roll shape curve function form suitable for the cold continuous rolling process of the ultra-high strength dual-phase steel DP1200X steel is as follows:

rack # 1:

rack # 2:

rack # 3:

rack # 4:

frame # 5:

the roll profile of the middle roll on the five stands for the cold continuous rolling process of DP1200X steel is given only in view of the mirror-symmetrical relationship of the roll profile of the lower middle roll and the roll profile of the upper middle roll, see in particular fig. 5.

Example 2

Ultra-high strength quenching is used for distributing steel QP980 steel grade (yield strength is 630MPa ≤ sigma)_sLess than 680MPa, tensile strength sigma_b1000MPa or more) as an example, the chemical composition of the steel grade is shown in Table 4:

table 4 QP980 high strength steel chemical composition (wt.%)

Chemical elements

C

Al

Ti

Nb

Mn

Cr

Content (wt.)

0.21～0.23

0.03～0.05

0.045～0.055

0.02～0.03

1.95～2.05

0.035～0.05

Chemical elements

Si

Ni

Mo

N

P

S

Content (wt.)

1.55～1.65

0.007～0.010

0.002～0.005

≤0.006

≤0.02

≤0.005

The thickness of a steel coil is 3.147mm, the width is 1255.0mm, the comprehensive plate shape value is 15.44IU, the thickness of a finished product strip steel is 1.612mm, and the high-strength steel is obtained by the classification: the steel belongs to a steel cluster S3(550MPa < sigma)_s＜700MPa)。

considering roll changing and re-starting under the high-temperature working condition, the steel coil belongs to a starting coil, the rolling speed setting calculation of the steel coil needs to follow the high-strength steel roll hot roll strategy, and the rolling speed of each rack is transited to the stable process speed through stepped speed increase, which is shown in table 5.

The unit tension is set as: the #1 rack entrance tension 184.4kN, the #1 rack exit tension 500.1kN, the additional tension 57.6kN, the #2 rack exit tension 492.5kN, the additional tension 62.6kN, the #3 rack exit tension 500.4kN, the additional tension 60.9kN, the #4 rack exit tension 311.7kN, and the #5 rack exit tension 59.8 kN.

The main process parameters of the unit are set as follows, see table 5:

TABLE 5 main technological parameters of cold continuous rolling process of QP980 steel

in this embodiment, the key evaluation parameter of the mechanism for influencing the evolution of the stress wave induced potential slab defect in the cold continuous rolling process should be a value corresponding to the steel type cluster S3, and the roll shape correlation coefficients of the intermediate roll for influencing the evolution of the stress wave induced potential slab defect of each stand are obtained as follows:

firstly, calculating the optimal transverse moving amount set value of the middle roller of the #1 machine frame of the steel grade cluster S3 as follows:

because, the intermediate roller reference traverse amount:

therefore, the first and second electrodes are formed on the substrate,

namely, the middle roller of the #1 machine frame moves forwards;

then, the optimal transverse displacement setting value of the middle rollers of the #2 to #5 frames of the steel grade cluster S3 can be calculated as follows:

the width coefficient of the cold-rolled strip steel is as follows:

i.e., the #5 frame center roller traverses negatively.

(3) Roll profile lateral coordinate position determination

Rack # 1:

and (3) upper intermediate roll:

a lower intermediate roll:

rack # 2:

and (3) upper intermediate roll:

a lower intermediate roll:

rack # 3:

and (3) upper intermediate roll:

a lower intermediate roll:

rack # 4:

and (3) upper intermediate roll:

a lower intermediate roll:

frame # 5:

and (3) upper intermediate roll:

a lower intermediate roll:

therefore, the first and second electrodes are formed on the substrate,

the middle rollers of the #2 to #5 frames transversely move in the negative direction; therefore, it is not only easy to use

therefore, it is not only easy to use

therefore, it is not only easy to use

therefore, the first and second electrodes are formed on the substrate,

according to the above, the second-order tilt coefficients of the intermediate roll shape curve equivalent of the steel grade clusters S2-S3 can be calculated in sequence as follows:

the second-order tilt coefficients of the intermediate roll shape curve equivalent of the steel grade clusters S2-S3 can be calculated in sequence as follows:

(5) intermediate roll shape curve function form

In summary, based on the stress wave induced plate shape evolution influence mechanism, the optimal intermediate roll shape curve function form suitable for the cold continuous rolling process of the QP980 steel grade of the ultrahigh-strength quenching distribution steel is as follows:

rack # 1:

rack # 2:

rack # 3:

rack # 4:

frame # 5:

the roll shape curve diagram of the middle roll on the five frames of the cold continuous rolling process of the QP980 steel grade is only given in consideration of the mirror symmetry relation of the roll shape curve of the lower middle roll and the roll shape curve of the upper middle roll, and particularly, the figure 6 is shown.

Example 3

High-strength dual-phase steel W780QX (yield strength 440MPa ≤ sigma)_sLess than 550MPa, tensile strength sigma_b780MPa) as an example, the chemical components of the steel grades are as follows, see Table 6:

TABLE 6W 780QX high Strength Steel chemical composition (wt.%)

Chemical elements	C	Cr	Al	Ti	Mn
						Content (wt.)	0.08～0.11	0.040～0.050	0.025～0.055	0.006～0.010	1.90～2.00
Chemical elements	P	N	Si	Nb	S
						Content (wt.)	≤0.020	≤0.004	1.10～1.20	0.001～0.003	≤0.004

The thickness of the steel coil is 4.412mm, the width is 1148.5mm, the comprehensive plate shape value is 14.39IU, the thickness of the finished product strip steel is 1.880mm, and the steel coil is obtained by the classification according to the high-strength steel layers: the steel belongs to a steel cluster S2(340MPa < sigma)_s≤550MPa)。

and considering the steel coil switching in the continuous rolling process, wherein the steel coil is not lifted and rolled, and the rolling speed setting calculation is completed by utilizing the rolling schedule.

The unit tension is set as: an inlet tension of 311.2kN for the #1 rack, an additional tension of 60.0kN, an outlet tension of 434.9kN for the #1 rack, an additional tension of 105.0kN, an outlet tension of 390.4kN for the #2 rack, an additional tension of 121.0kN, an outlet tension of 391.2kN for the #3 rack, an additional tension of 53.0kN, an outlet tension of 321.4kN for the #4 rack, an additional tension of 47.0kN, an outlet tension of 86.9kN for the #5 rack, and an additional tension of 40.0 kN.

The main process parameters of the unit are set as follows, see table 7:

TABLE 7 main technological parameters of the cold continuous rolling process of W780QX steel

in this embodiment, the key evaluation parameter of the mechanism for influencing the evolution of the stress wave induced potential slab defect in the cold continuous rolling process should be a value corresponding to the steel type cluster S2, and the roll shape correlation coefficients of the intermediate roll for influencing the evolution of the stress wave induced potential slab defect of each stand are obtained as follows:

firstly, calculating the optimal transverse moving amount set value of the middle roller of the #1 machine frame of the steel grade cluster S2 as follows:

because, the intermediate roller reference traverse amount:

therefore, the first and second electrodes are formed on the substrate,

namely, the middle roller of the #1 machine frame moves forwards;

then, the optimal transverse displacement setting value of the middle rollers of the #2 to #5 frames of the steel grade cluster S2 can be calculated as follows:

the width coefficient of the cold-rolled strip steel is as follows:

namely, the middle roller of the #2 machine frame moves forwards;

namely, the middle roller of the #3 machine frame moves forwards;

namely, the middle roller of the #4 machine frame moves forwards;

i.e., the #5 frame center roller is traversing in the forward direction.

(3) Roll profile lateral coordinate position determination

Rack # 1:

and (3) upper intermediate roll:

a lower intermediate roll:

rack # 2:

and (3) upper intermediate roll:

a lower intermediate roll:

rack # 3:

and (3) upper intermediate roll:

a lower intermediate roll:

rack # 4:

and (3) upper intermediate roll:

a lower intermediate roll:

frame # 5:

and (3) upper intermediate roll:

a lower intermediate roll:

as described above, the intermediate rolls of the frames #1 to #5 are forwardly moved laterally; taking the reference geometric amplitude of the roller shape curve of the intermediate roller:

therefore, the first and second electrodes are formed on the substrate,

therefore, the first and second electrodes are formed on the substrate,

the middle rollers of the #1 to #5 frames move transversely in the positive direction; taking a first-order inclination coefficient of a middle roller profile reference:

therefore, the first and second electrodes are formed on the substrate,

the middle rollers of the #1 to #5 frames move transversely in the positive direction; taking the second-order inclination coefficient of the roller profile curve reference of the intermediate roller:

according to the foregoing, the second-order tilt coefficients of the intermediate roll shape curve equivalent of the steel seed cluster S2 can be calculated as:

(5) intermediate roll shape curve function form

To sum up, based on the stress wave induced plate shape evolution influence mechanism, the optimal intermediate roll shape curve function form suitable for the high-strength dual-phase steel W780QX cold continuous rolling process is as follows:

rack # 1:

rack # 2:

rack # 3:

rack # 4:

frame # 5:

the roll profile of the middle roll on the five stands of the cold continuous rolling process of the W780QX steel grade is given only in view of the mirror symmetry relationship of the roll profile of the lower middle roll and the roll profile of the upper middle roll, see in particular fig. 7.

The present invention has been described in detail with reference to the specific embodiments and the exemplary embodiments, but the description should not be construed as limiting the present invention. Those skilled in the art will appreciate that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its embodiments without departing from the spirit and scope of the present invention, which fall within the scope of the present invention. The scope of the invention is defined by the appended claims.

Claims

1. A method for designing the shape of a middle roller of a five-frame six-roller cold continuous rolling unit is characterized by comprising the following steps:

2. The intermediate roll shape design method of claim 1, wherein the establishing of the shape defect evolution model according to the rolling parameters of the intermediate rolls of each stand and the high-strength steel grade cluster comprises:

wherein the content of the first and second substances,

3. The method for designing the roll shape of the intermediate roll according to claim 1, wherein the establishing of the optimal transverse displacement regulating and controlling matrix of the intermediate roll of each rack according to the plate shape defect evolution model comprises the following steps:

wherein, B_αIs the width coefficient of the cold-rolled steel strip,

a reference length is calculated for the intermediate roll body crown.

4. The method for designing the intermediate roll shape according to claim 1, wherein the calculating the parameters of the roll shape curve model of each frame intermediate roll shape according to the plate shape defect evolution model comprises:

wherein the content of the first and second substances,

wherein the content of the first and second substances,

wherein the content of the first and second substances,

wherein the content of the first and second substances,

wherein the content of the first and second substances,

5. The method for designing the roll shape of the intermediate roll as claimed in claim 1, wherein the step of establishing the roll shape curve model of the intermediate roll of each frame according to the spatial coordinate system and the parameters of the roll shape curve model of the intermediate roll of each frame comprises the following steps:

wherein the content of the first and second substances,

calculating a reference length for the crown of the intermediate roll body;

wherein the content of the first and second substances,

the ith frame is used when the high-strength steel is a steel grade cluster Ss under the space coordinateGrinding the roll diameter at the x position on the roll shape curve by using a lower intermediate roll;

6. The utility model provides a five frames six roller cold continuous rolling mill group middle roll shape design devices which characterized in that includes:

7. The intermediate roll shape design device according to claim 6, wherein the second building block comprises:

wherein the content of the first and second substances,

when the high-strength steel is a steel cluster Ss, the stress wave induces the critical state geometric characteristic value, namely the geometric disturbance quantity, of the evolution of the potential plate defect withoutDimension;

8. The intermediate roll shape design device of claim 6, wherein the third building block comprises:

wherein, B_αIs the width coefficient of the cold-rolled steel strip,

a reference length is calculated for the intermediate roll body crown.

9. The intermediate roll shape design apparatus of claim 6, wherein the calculation module comprises:

wherein the content of the first and second substances,

wherein the content of the first and second substances,

wherein the content of the first and second substances,

wherein the content of the first and second substances,

the high-strength steel is steelThe roller shape curve equivalent first-order inclination coefficient of the intermediate roller is dimensionless when the cluster Ss is planted;

wherein the content of the first and second substances,

is high in strengthWhen the steel is a steel grade cluster Ss, the stress waves of all the frames induce the evolution of potential plate shape defects to influence the mean square value of the roller shape of the intermediate roller, and the mean square value is dimensionless;

10. The intermediate roll shape design device of claim 6, wherein the fourth building block comprises:

wherein the content of the first and second substances,

calculating a reference length for the crown of the intermediate roll body;

is made of high-strength steelSetting the optimal transverse moving amount of the ith frame intermediate roll during steel grade cluster Ss;

wherein the content of the first and second substances,