阅读说明：本技术 适用于核电锆合金板带轧制的支持辊及辊形加工方法 (Support roller suitable for rolling nuclear power zirconium alloy plate strip and roll shape processing method ) 是由 曹建国 张兆祥 王犇 高博 王雷雷 张鹏飞 张志豪 罗倩倩 曹媛 齐伟 宋纯宁 于 2021-08-31 设计创作，主要内容包括：本申请公开了一种适用于核电锆合金板带轧制的支持辊及辊形加工方法,支持辊的接触段(10)的直径沿支持辊的轴向自所述接触段(10)的中心向两端逐渐减小,所述接触段(10)包括：主体长度段(1)；两个变接触段(2),分别与所述主体长度段(1)的两端连接；结构锥度段(3)；所述变接触段(2)至少包括第一变接触段(21)和第二变接触段(22),所述第一变接触段(21)相对所述第二变接触段(22)距离所述主体长度段(1)更近,所述第一变接触段(1)的直径变化率大于所述主体长度段(1)的直径变化率,小于所述第二变接触段(22)的直径变化率。本申请能够应对超多轧制道次下使用单一变接触段时造成的辊间接触压力过大的问题。(The application discloses back-up roll and roll shape processing method suitable for nuclear power zirconium alloy slab band rolling, the diameter of the contact segment (10) of back-up roll reduces from the center of contact segment (10) to both ends along the axial of back-up roll gradually, contact segment (10) include: a main body length section (1); the two variable contact sections (2) are respectively connected with two ends of the main body length section (1); a structural taper section (3); the variable contact section (2) at least comprises a first variable contact section (21) and a second variable contact section (22), the first variable contact section (21) is closer to the main body length section (1) than the second variable contact section (22), and the diameter change rate of the first variable contact section (1) is larger than that of the main body length section (1) and smaller than that of the second variable contact section (22). The problem that contact pressure between the rollers is too large when a single variable contact section is used under more rolling passes can be solved.)

1. A backup roll suitable for rolling a nuclear power zirconium alloy plate strip, wherein the diameter of a contact section (10) of the backup roll is gradually reduced from the center of the contact section (10) to two ends along the axial direction of the backup roll, and the contact section (10) comprises:

a main body length section (1);

the two variable contact sections (2) are respectively connected with two ends of the main body length section (1);

the variable contact section (2) at least comprises a first variable contact section (21) and a second variable contact section (22), the first variable contact section (21) is closer to the main body length section (1) than the second variable contact section (22), and the diameter change rate of the first variable contact section (21) is larger than that of the main body length section (1) and smaller than that of the second variable contact section (22).

2. Backup roll according to claim 1, wherein the contact section (10) further comprises:

the two structure taper sections (3) are respectively connected with the second variable contact sections (22), and the diameter change rate of the structure taper sections (3) is larger than that of the second variable contact sections (22).

3. The back-up roll according to claim 2, wherein the contact section (10) is symmetrical about a central plane of the contact section (10), the central plane is a plane passing through the center of the contact section (10) and perpendicular to the axis of the contact section (10), and the generatrices of the main body length section (1), the first variable contact section (21), the second variable contact section (22) and the structural taper section (3) are all cosine function curves with the intersection point of the generatrices of the contact section (10) and the central plane as a coordinate origin.

4. Backup roll according to claim 3, wherein the cosine function curve of the generatrix of the body length section (1) is:

wherein X represents the coordinate on the X-axis, and L represents the axial length of the contact segment, all in mm; k represents the conventional adjusting coefficient of the roll shape of the supporting roll, and the value range is 0-656.58 mm; theta represents the conventional adjusting angle of the roll shape of the supporting roll, and the value range of theta is 0-90 degrees.

5. Backup roll according to claim 4, wherein the cosine function curves of the generatrices of the two first variable contact sections (21) are respectively:

wherein X represents a coordinate on the X-axis in mm; l is₁The total length of the first variable contact section, the second variable contact section and the structural taper section which represent the single side of the contact section has the value range ofk₁To representA first adjusting coefficient of the roll shape of the supporting roll is 0.01-9848.67 mm; theta₁The first adjusting angle of the roll shape of the supporting roll is shown, and the value range is 0-90 degrees.

6. Backup roll according to claim 5, wherein the cosine function curves of the generatrices of the two second variable contact sections (22) are respectively:

wherein X represents a coordinate on the X-axis in mm; l is₂The total length of the first variable contact section and the structural taper section on one side of the contact section is represented, and the value range isk₂The second adjustment coefficient of the roll shape of the supporting roll is 0.01-9848.67 mm; theta₂And the second adjusting angle of the roll shape of the supporting roll is represented, and the value range is 0-90 degrees.

7. Backup roll according to claim 6, wherein the cosine function curves of the generatrices of the two structural taper sections (3) are respectively:

wherein X represents a coordinate on the X-axis in mm; l is₃The length of the structural taper section on one side of the contact section is takenA value range ofk₃Representing a third adjusting coefficient of the roll shape of the supporting roll, wherein the value range is 0.5-9848.67 mm; theta₃And the third adjusting angle of the roll shape of the supporting roll is represented, and the value range is 0-90 degrees.

8. A backup roller according to claim 1, wherein the variable contact section (10) further comprises a third variable contact section that is farther from the body length section (1) than the second variable contact section (22), the third variable contact section having a rate of change of diameter that is greater than the rate of change of diameter of the second variable contact section (22).

9. The backup roll of claim 8, wherein the contact section further comprises:

and the two structure taper sections (3) are respectively connected with the third variable contact section, and the diameter change rate of the structure taper sections (3) is greater than that of the third variable contact section.

10. A method for processing roll shape of a backup roll suitable for rolling nuclear power zirconium alloy plate strips comprises the following steps:

s1, providing an original roller;

s2, processing the original roller to obtain the supporting roller of claim 4;

s3, processing the supporting roller obtained in the step S2 to obtain the supporting roller of claim 5;

s4, processing the supporting roller obtained in the step S3 to obtain the supporting roller of claim 6;

s5, processing the supporting roller obtained in the step S4 to obtain the supporting roller as claimed in claim 7.

Technical Field

The application relates to the technical field of strip rolling, in particular to a support roller suitable for rolling a nuclear power zirconium alloy strip and a roll shape processing method of the support roller.

Background

The plate shape quality of the nuclear power zirconium alloy plate strip is taken as one of key quality indexes, and the improvement of the plate shape quality of the nuclear power zirconium alloy plate strip has important significance for autonomous controllable manufacturing of the nuclear power zirconium alloy plate strip. At present, a multi-roll-range multi-width ultra-multi-pass (dozens of passes) rolling is usually realized by adopting a multi-roll-set roll system of a rolling mill, and a working roll and a supporting roll are in complete contact under a conventional roll-shape roll system configuration scheme, so that a harmful contact line is large, the working roll is seriously bent and deformed, the plate shape quality of nuclear zirconium alloy plates with different rolling widths is influenced, and the problems of insufficient plate shape regulation capability and plate shape quality defect in the complex rolling process of the nuclear zirconium alloy plates are caused.

Disclosure of Invention

The embodiment of the application provides a support roller suitable for rolling a nuclear power zirconium alloy plate strip and a roller shape processing method, which can solve the problem of overlarge contact pressure between rollers when a single variable contact section is used under super-multiple rolling passes, and ensure the quality of the plate shape in the rolling process.

A first aspect of the embodiments of the present application provides a back-up roll suitable for rolling a nuclear power zirconium alloy plate strip, a diameter of a contact section of the back-up roll gradually decreases from a center of the contact section to both ends along an axial direction of the back-up roll, and the contact section includes: a body length section; the two variable contact sections are respectively connected with two ends of the length section of the main body; the variable contact section at least comprises a first variable contact section and a second variable contact section, the first variable contact section is closer to the main body length section than the second variable contact section, and the diameter change rate of the first variable contact section is greater than that of the main body length section and smaller than that of the second variable contact section.

In some embodiments, the contact section further comprises: and the two structure taper sections are respectively connected with the second variable contact section, and the diameter change rate of the structure taper sections is greater than that of the second variable contact section.

In some embodiments, the contact section is symmetrical about a central plane of the contact section, the central plane is a plane passing through the center of the contact section and perpendicular to the axis of the contact section, and the generatrices of the main body length section, the first variable contact section, the second variable contact section and the structural taper section are all cosine function curves with the intersection point of the generatrices of the contact section and the central plane as a coordinate origin.

In some embodiments, the cosine function curve of the generatrix of the body length section is:

wherein X represents the coordinate on the X-axis, and L represents the axial length of the contact segment, all in mm; k represents the conventional adjusting coefficient of the roll shape of the supporting roll, and the value range is 0-656.58 mm; theta represents the conventional adjusting angle of the roll shape of the supporting roll, and the value range of theta is 0-90 degrees.

In some embodiments, the cosine function curves of the generatrices of the two first contact-changing sections are respectively:

wherein X represents a coordinate on the X-axis in mm; l is₁The total length of the first variable contact section, the second variable contact section and the structural taper section which represent the single side of the contact section has the value range ofk₁The first adjusting coefficient of the roll shape of the supporting roll is represented, and the value range is 0.01-9848.67 mm; theta₁The first adjusting angle of the roll shape of the supporting roll is shown, and the value range is 0-90 degrees.

In some embodiments, the cosine function curves of the generatrices of the two second contact-changing sections are respectively:

wherein X represents a coordinate on the X-axis in mm; l is₂The total length of the first variable contact section and the structural taper section on one side of the contact section is represented, and the value range isk₂The second adjustment coefficient of the roll shape of the supporting roll is 0.01-9848.67 mm; theta₂And the second adjusting angle of the roll shape of the supporting roll is represented, and the value range is 0-90 degrees.

In some embodiments, the cosine function curves of the generatrices of the two structural taper sections are respectively:

wherein X represents a coordinate on the X-axis in mm; l is₃The length of the structural taper section at one side of the contact section is represented, and the value range isk₃Representing a third adjusting coefficient of the roll shape of the supporting roll, wherein the value range is 0.5-9848.67 mm; theta₃And the third adjusting angle of the roll shape of the supporting roll is represented, and the value range is 0-90 degrees.

In some embodiments, the variable contact section further comprises a third variable contact section that is further from the body length section than the second variable contact section, the third variable contact section having a rate of change of diameter that is greater than the rate of change of diameter of the second variable contact section.

In some embodiments, the contact section further comprises: and the two structural taper sections are respectively connected with the third variable contact section, and the diameter change rate of the structural taper sections is greater than that of the third variable contact section.

A second aspect of the embodiments of the present application provides a method for roll forming a backup roll suitable for rolling a nuclear power zirconium alloy plate strip, including:

s1, providing an original roller;

s2, processing the original roller to obtain the supporting roller of the previous embodiment;

s3, processing the supporting roller obtained in the step S2 to obtain the supporting roller of the previous embodiment;

s4, processing the supporting roller obtained in the step S3 to obtain the supporting roller of the previous embodiment;

s5, processing the supporting roller obtained in the step S4 to obtain the supporting roller of the previous embodiment.

The above technical embodiments of the present application have the following beneficial technical effects:

the roller shape of the support roller comprises a main body length section, a first variable contact section, a second variable contact section and a structural taper section, wherein when a narrow plate strip with a narrower width is rolled, the first variable contact section plays a variable contact function, the length of a contact line between rollers is self-adaptive to the rolling width by combining rolling force, and the length of a harmful contact line and the harmful deflection deformation of a working roller are reduced; when the width of a plate strip or a rolled piece with a wider rolling width is increased, the first variable contact section is used as an arc transition, and the second variable contact section replaces the first variable contact section to play a variable contact function, so that the problem of overlarge contact pressure between rollers when a single variable contact section is used under more rolling passes is solved, and the quality of the plate shape in the rolling process is ensured.

The noun explains:

the diameter change rate refers to the ratio of the change of the diameter per unit length along the axial direction of the contact section of the support roller to the unit length.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic view of a curved surface of a backup roll provided in an embodiment of the present application;

FIG. 2 is a schematic diagram of multiple cosine function grinding of a contact surface of a backup roll provided in an embodiment of the present application;

FIG. 3 is a schematic diagram of a roll shape curve of a backup roll with different roll shape parameters provided by an embodiment of the present application;

FIG. 4 is a schematic diagram comparing the roll gap stiffness of a backup roll provided in the examples of the present application with a conventional flat roll;

FIG. 5 is a schematic diagram showing the roll bending control comparison between the backup roll and the conventional flat roll provided in the examples of the present application.

In the figure, 10, the contact section; 1. a body length section; 2. a variable contact section; 21. a first variable contact section; 22. a second variable contact section; 3. and (5) a structural taper section.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below with reference to the accompanying drawings in combination with the detailed description. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present application. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present application.

In the research process of the applicant, in the technical field of strip rolling, a working roll and a supporting roll are in complete contact under a conventional roll-shaped roll system configuration scheme, and a harmful contact line is large, so that the working roll is seriously bent and deformed, and the strip shape quality is influenced. This is because the contact line between the work roll and the backup roll exceeds the rolling width (strip width), and the existence of this overhang segment is the main cause of instability of roll gap crown due to excessive deflection of the work roll and rolling force fluctuation, so this overhang segment is called "detrimental contact line". In order to reduce or eliminate harmful contact lines and improve the effect of regulating and controlling the effect of a bending roll, researchers provide a variable contact supporting roll, the roll shape curve of the existing variable contact supporting roll comprises a variable contact section, when the variable contact section is used for a rolled piece with fixed width, the variable contact section can reduce the harmful contact lines and improve the effect of regulating and controlling the bending roll, however, when one set of rolling mill is suitable for strips with different widths under multiple rolling processes and super multiple rolling passes, the length of the harmful contact lines can also be changed, the length of the harmful contact lines between the rolls and the rolling width can not be ensured to be self-adaptive by a single variable contact section, so that the contact pressure between a working roll and the supporting roll is overlarge when the strips with different widths are met, and the strip shape quality is influenced.

For the above reasons, the present embodiment provides a back-up roll suitable for rolling a nuclear power zirconium alloy plate strip, as shown in fig. 1, a diameter of a contact section 10 of the back-up roll gradually decreases from a center of the contact section 10 to both ends along an axial direction of the back-up roll, where the contact section 10 includes: a main body length section 1; the two variable contact sections 2 are respectively connected with two ends of the main body length section 1; the variable contact section 2 at least comprises a first variable contact section 21 and a second variable contact section 22, the first variable contact section 21 is closer to the main body length section 1 than the second variable contact section 22, and the diameter change rate of the first variable contact section 21 is larger than that of the main body length section 1 and smaller than that of the second variable contact section 22.

In the embodiment, the contact surface of the support roller comprises a main body length section 1, a first variable contact section 21, a second variable contact section 22 and a structural taper section 3, when a narrow plate strip is rolled, the first variable contact section 21 plays a variable contact function, the length of a contact line between the rollers is self-adaptive to the rolling width by combining the rolling force, and the length of a harmful contact line and the harmful deflection deformation of a working roller are reduced; when the width of a rolled wide plate strip or a rolled piece is increased, the first variable contact section 21 is used as an arc transition, and the second variable contact section 22 replaces the first variable contact section 21 to play a variable contact function, so that the problem of overlarge contact pressure between rollers when a single variable contact section is used under more rolling passes is solved, and the plate shape quality in the rolling process is ensured.

Further, the contact section 10 further comprises: and the two structural taper sections 3 are respectively connected with the second variable contact sections 22, and the diameter change rate of the structural taper sections 3 is greater than that of the second variable contact sections 22.

In some embodiments, the contact section 10 is symmetrical about a central plane of the contact section 10, the central plane is a plane passing through the center of the contact section 10 and perpendicular to the axis of the contact section 10, and the generatrices of the main body length section 1, the first variable contact section 21, the second variable contact section 22 and the structural taper section 3 are all cosine function curves with the intersection point of the generatrices of the contact section 10 and the central plane as a coordinate origin. Wherein:

the cosine function curve of the generatrix of the main body length section is as follows:

wherein X represents the coordinate on the X-axis, and L represents the axial length of the contact segment, all in mm; k represents the conventional adjusting coefficient of the roll shape of the supporting roll, and the value range is 0-656.58 mm; theta represents the conventional adjusting angle of the roll shape of the supporting roll, and the value range of theta is 0-90 degrees.

The cosine function curves of the generatrices of the two first variable contact sections are respectively as follows:

wherein X represents a coordinate on the X-axis in mm; l is₁The total length of the first variable contact section, the second variable contact section and the structural taper section which represent the single side of the contact section has the value range ofk₁The first adjusting coefficient of the roll shape of the supporting roll is represented, and the value range is 0.01-9848.67 mm; theta₁The first adjusting angle of the roll shape of the supporting roll is shown, and the value range is 0-90 degrees.

The cosine function curves of the generatrices of the two second variable contact sections are respectively as follows:

wherein X represents a coordinate on the X-axis in mm; l is₂The total length of the first variable contact section and the structural taper section on one side of the contact section is represented, and the value range isk₂The second adjustment coefficient of the roll shape of the supporting roll is 0.01-9848.67 mm; theta₂And the second adjusting angle of the roll shape of the supporting roll is represented, and the value range is 0-90 degrees.

The cosine function curves of the generatrices of the two structural taper sections are respectively as follows:

wherein X represents a coordinate on the X-axis in mm; l is₃The length of the structural taper section at one side of the contact section is represented, and the value range isk₃Representing a third adjusting coefficient of the roll shape of the supporting roll, wherein the value range is 0.5-9848.67 mm; theta₃And the third adjusting angle of the roll shape of the supporting roll is represented, and the value range is 0-90 degrees.

In some embodiments, the variable contact section 10 further comprises a third variable contact section that is further from the body length section 1 than the second variable contact section 22, the third variable contact section having a rate of change of diameter that is greater than the rate of change of diameter of the second variable contact section 22.

In the embodiment, a third variable contact section is additionally arranged on the basis of the two variable contact sections in the embodiment, and based on the self-adaptive capacity of the contact line length and the rolling width between the different variable contact sections and the roll pair, the third variable contact section can replace the second variable contact section 22 to play the variable contact function when the width of a rolled wide plate strip or a rolled piece is increased.

Further, the contact section 10 further comprises: and the two structural taper sections 3 are respectively connected with the third variable contact section, and the diameter change rate of the structural taper sections 3 is greater than that of the third variable contact section.

A second aspect of the embodiments of the present application provides a method for roll forming a backup roll suitable for rolling a nuclear power zirconium alloy plate strip, including:

s1, providing an original roller;

s2, processing the original roller to obtain the supporting roller of the previous embodiment, wherein the supporting roller is provided with a main body length section 1;

s3, processing the supporting roller obtained in the step S2 to obtain the supporting roller of the previous embodiment, wherein the supporting roller is provided with a first variable contact section 21;

s4, processing the supporting roller obtained in the step S3 to obtain the supporting roller of the previous embodiment, wherein the supporting roller is provided with a second variable contact section 22.

S5, processing the supporting roller obtained in step S4 to obtain the supporting roller of the previous embodiment, wherein the supporting roller is formed with a structural taper section 3.

In other embodiments, the original roll may be processed and the body length segment 1, the first varied contact segment 21, the second varied contact segment 22, and the structural taper segment 3 may be formed simultaneously on the original roll, and the body length segment 1, the first varied contact segment 21, the second varied contact segment 22, and the structural taper segment 3 may also be formed in other orders.

The scheme of the embodiment is described below by taking a 750mm single-stand reversible mill train for nuclear zirconium alloy plate strips as an example.

The length of the main body of the back-up roll is symmetrical to the middle point of the roll body. When theta is 0 degrees, the roller is formed into a flat roller, and the selection of the coefficient k loses significance; when theta is more than or equal to 1 degree and less than or equal to 90 degrees, the middle part of the roller body curve is a convexity roller. In the case of θ determination, the curve convexity value C can be adjusted by a coefficient k, the relationship between them being:

when theta is 90 degrees, k belongs to [0, 0.1] according to curve convexity C belonging to [0mm, 0.1mm ]; when θ is 1 °, k ∈ [0, 656.58] is obtained from the curve convexity C ∈ [0mm, 0.1mm ].

The first contact section is aboutTwo sections of curves with symmetrical midpoints of the roller bodies have the contact changing regulation and control effect when narrow rolled pieces are rolled, and serve as an arc function when wide rolled pieces are rolled, so that the degree of uneven contact pressure between the rollers is reduced. When theta is₁When the angle is equal to 0 degrees, the contact section is changed into a flat roller; when the angle is less than or equal to 1 DEG theta₁When the angle is less than or equal to 90 degrees, the contact section is changed into a curve, and the angle theta can be adjusted₁And adjusting the shape of the curve. At theta₁After determination, by the coefficient k₁Adjusting the depth h of the curve₁The relationship between them is:

when theta is₁When the angle is 90 DEG, the curve depth h₁∈[0.01mm，1.5mm]To obtain k₁∈[0.01，1.5](ii) a When theta is₁1 DEG, measured by curve depth h₁∈[0.01mm，1.5mm]To obtain k₁∈[65.66，9848.67]。

The second variable contact section is likewise a two-segment curve which is symmetrical about the center point of the roll body and serves as a variable contact section when rolling wide products. When theta is₂When the angle is equal to 0 degrees, the second variable contact section is a flat roller; when the angle is less than or equal to 1 DEG theta₃When the angle is less than or equal to 90 degrees, the second contact changing section is a curve and can be adjusted by theta₂And adjusting the shape of the second variable contact section. At theta₂After determination, by the coefficient k₂Adjusting the second variable contact section depth h₂The relationship between them is:

when theta is₂When the angle is 90 DEG, the curve depth h₂∈[0.01mm，1.5mm]To obtain k₂∈[0.01，1.5](ii) a When theta is₂1 DEG, measured by curve depth h₂∈[0.01mm，1.5mm]To obtain k₂∈[65.66，9848.67]。

The structural taper section is also two sections of curves which are symmetrical about the midpoint of the roll body and serves as the structural taper section when the wide rolled piece is rolled. When theta is₃＝0At an angle, the structural taper section is a flat roller; when the angle is more than or equal to 1 degree and less than or equal to 90 degrees, the structural taper section is a curve and can be adjusted by theta₃And adjusting the shape of the taper section of the structure. At theta₃After determination, by the coefficient theta₃Adjusting the depth h of the taper section of the structure₃The relationship between them is:

when theta is₃When the angle is 90 degrees, the depth h of the taper section is determined by the structure₃∈[0.5mm，1.5mm]To obtain k₃∈[0.5，1.5](ii) a When theta is₃When 1 degree, the depth h of the taper section is determined by the structure₃∈[0.5mm，1.5mm]To obtain k₃∈[3282.89，9848.67]。

Example 1:

a roll shape curve 1 is designed according to the roll shape coefficient of the support roll of the nuclear zirconium alloy selected in the table 1, and as shown in fig. 3, when all roll shape angles are 0 degrees, the roll shape is a conventional flat roll.

TABLE 1 coefficients corresponding to curve 1 of the roll shape of the backing roll

Example 2:

the roll profile curve 2 is designed according to the roll profile coefficient of the support roll of the nuclear zirconium alloy selected in the table 2, and as shown in fig. 3, the roll profile of the support roll has the variable contact characteristic, the maximum roll diameter difference is about 0.22mm, and the method is generally suitable for the situation that the rolling force of a multi-pass single-stand reversible rolling mill is small.

TABLE 2 coefficients corresponding to curve 2 of the backup roll profile

Example 3:

a roll shape curve 3 is designed according to the roll shape coefficient of the support roll of the nuclear zirconium alloy selected in the table 3, and as shown in fig. 3, the roll shape of the support roll has the variable contact characteristic, the maximum roll diameter difference is about 0.91mm, and the method is generally suitable for the subsequent pass occasions of a multi-pass single-stand reversible rolling mill.

TABLE 3 coefficients corresponding to curve 3 of backup roll profile

Example 4:

the roll profile curve 4 is designed according to the roll profile coefficient of the support roll of the nuclear zirconium alloy selected in the table 4, and as shown in fig. 3, the roll profile of the support roll has the variable contact characteristic, the maximum roll diameter difference is about 1.3mm, and the method is generally suitable for the previous pass occasion of a multi-pass single-stand reversible rolling mill.

TABLE 4 coefficients corresponding to curve 4 of backup roll profile

Example 5:

the roll shape curve 5 is designed according to the roll shape coefficient of the support roll of the nuclear zirconium alloy selected in the table 5, as shown in fig. 3, it can be seen that the roll shape of the support roll has obvious variable contact characteristics, the variable contact section and the chamfering section of the roll shape curve have large depths, the maximum roll diameter difference reaches about 2.8mm, and the method is generally suitable for occasions with large rolling force of a multi-rolling-pass single-stand reversible rolling mill.

TABLE 5 coefficients corresponding to the backup roll profile curve 5

Example 6:

it can be seen from examples 1 to 5 that when all the roll shape angles of the backup roll are 0, the roll shape of the backup roll is a regular flat roll. When the roll shape angle of the backup roll is not zero, the backup roll has a variable contact characteristic except for the roll shape. Different roll shapes of the support roll are suitable for different rolling mills to match different roll shapes of the working roll and different rolling force conditions, and for a single-stand reversible rolling mill suitable for multi-pass rolling of nuclear zirconium alloy plate strips, a roll shape curve of the designed roll shape of the support roll suitable for nuclear zirconium alloy is shown in figure 1 by optimizing a roll shape coefficient (shown in a table 6).

TABLE 6 optimization of coefficients corresponding to the profile curves of the backup rolls

As shown in fig. 4, finite element simulation analysis is performed by taking the nuclear zirconium alloy with multiple rolling processes and multiple passes as an example, and the result shows that as shown in table 7, the transverse rigidity is gradually increased in the rolling process, but the transverse rigidity (the variation of the rolling force under the unit roll gap crown variation) of the variable contact back-up roll in the new scheme is improved compared with that of the conventional flat roll, so that the variable contact back-up roll has stronger roll gap crown self-holding capacity; by comparing the variable contact backup roll of the nuclear zirconium alloy plate strip with different widths with the roll bending efficiency regulation and control of a conventional flat roll pair rolling mill, as shown in FIG. 5, when the roll bending force is increased from-100 kN to +180kN, the roll gap crown variation of the variable contact backup roll and the conventional flat roll is 43.70 μm and 50.98 μm respectively, and the roll bending force regulation and control efficiency is improved by 16.66%; the analysis proves that the variable contact supporting roller shape can be suitable for multi-width multi-pass rolling of the nuclear power zirconium alloy, the plate shape regulation and control capability is obviously enhanced, the length of harmful contact lines between the rollers is effectively eliminated, the harmful deflection deformation of the working roller is reduced, and the variable contact supporting roller shape has great significance for improving the plate shape quality of the nuclear power zirconium alloy.

TABLE 7 comparison of the transverse stiffness of the corresponding passes of the two schemes

Item	Pass 1	Pass 14	Pass 27	Pass 36	Pass 39	Pass 56
							Con/μm	39.31	49.70	56.22	58.97	36.71	54.13
VCR/μm	46.20	53.53	64.14	66.13	44.58	64.99
							Percentage of	17.55％	7.70％	14.10％	12.13％	21.44％	20.07％

It is to be understood that the above-described embodiments of the present application are merely illustrative of or illustrative of the principles of the present application and are not to be construed as limiting the present application. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present application shall be included in the protection scope of the present application. Further, it is intended that the appended claims cover all such changes and modifications that fall within the scope and range of equivalents of the appended claims, or the equivalents of such scope and range.