A variable crown work roll for improving the velocity of strip steel and its roll shape design method

Abstract

This invention discloses a variable crown work roll and its roll shape design method for improving the mountain-shaped cross-section of strip steel, belonging to the field of steel rolling automation technology. The roll shape of this variable crown work roll is formed by superimposing a cubic curve and a roll body compensation curve based on the "mountain"-shaped cross-section. The roll body compensation curve is formed by segmentally superimposing compensation functions for the edge adjustment zone, the rib adjustment zone, and compensation functions for other positions outside the adjustment zone, with smooth connections between each region. In the roll shape design, the roll body compensation curve is obtained by designing the edge adjustment zone compensation curve and the rib adjustment zone compensation curve. The final work roll shape curve is obtained by superimposing the cubic curve and the roll body compensation curve. This invention, by designing a reasonable work roll shape curve and combining it with the "mountain"-shaped cross-section characteristics, increases the amount of pressure applied by the work roll to the edge of the strip steel and reduces the amount of pressure applied to the ribs, thereby achieving the purpose of eliminating the "mountain"-shaped cross-section of the strip steel.

Description

Technical Field

[0001] This invention belongs to the field of steel rolling automation technology, and specifically relates to a variable convexity work roll for improving the mountain-shaped cross-section of strip steel and its roll shape design method. Background Technology

[0002] With the development of rolling technology, producing high-quality strip steel products has become a common goal pursued by major strip processing enterprises. As one of the important evaluation indicators of hot-rolled strip shape quality, cross-sectional profile control has always been a key challenge for manufacturers. For products such as cold-rolled base materials that require downstream processing, the smoothness of the cross-sectional profile during hot rolling directly determines the final cross-sectional profile quality of the product. Furthermore, poor cross-sectional profile control during hot rolling can also lead to complex waviness in downstream processes such as finishing and cold rolling, affecting production stability.

[0003] "Mountain"-shaped profile defects in strip steel frequently occur during wide-span rolling mill production. Unlike traditional localized high-point defects, which become increasingly prominent in the later stages of rolling, "mountain"-shaped profile defects can appear as early as the early to mid-stages of rolling. Traditionally, controlling the profile involves developing a rational reciprocating roll-shifting strategy to even out roll wear. However, wide-span rolling mills typically employ CVC (Continuous Vibration Control) rolling, meaning that when a "mountain"-shaped profile appears on-site, operators can only intervene by manipulating the roll bending force. This strategy also easily leads to a decrease in crown and flatness accuracy.

[0004] It is worth noting that the "mountain" shaped cross-section exacerbates localized wear on the work rolls and coiler pinch rolls. In the later stages of rolling, the control of the cross-sectional profile and flatness will gradually deteriorate, potentially leading to surface quality defects in the strip. Currently, there are no effective means to control "mountain" shaped cross-sectional profile defects on-site. Summary of the Invention

[0005] To address the problem of "mountain" shaped cross-section defects that easily occur during the production of wide-width rolling mills, this invention provides a variable convexity work roll and its roll shape design method to improve the mountain-shaped cross-section of strip steel.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] This invention provides a variable crown work roll for improving the "mountain" shaped cross-section of strip steel, comprising an edge adjustment zone, a middle adjustment zone, and other areas outside the adjustment zones. The edge adjustment zone is used to increase the edge compression of the strip steel and to smoothly connect with the roll shape outside the strip steel area; the rib adjustment zone is used to increase the compression of the strip steel ribs.

[0008] The working roll shape of this invention is formed by superimposing a cubic curve and a roll body compensation curve based on a mountain-shaped cross section. The roll body compensation curve is formed by superimposing the compensation function of the edge adjustment area, the compensation function of the rib adjustment area, and the compensation function of other positions outside the adjustment area in segments, and the connection between each area is smooth.

[0009] The formula for calculating the ordinate of the work roll profile is:

[0010] y0(x)=a1x+a2x 2 +a3x 3

[0011] y(x) = y0(x) + y1(x)

[0012] Where y0(x) is a cubic curve function, and a1, a2, a3 are the coefficients of the cubic curve polynomial;

[0013] y(x) is the curve function of the working roll shape designed in this invention;

[0014] y1(x) is the roller body compensation curve function;

[0015] The calculation process for a1, a2, and a3 is as follows:

[0016] a1 = -a2L - 3a3(L / 2) 2 -a3B 2 / 4

[0017]

[0018]

[0019] Where L is the length of the work roll body; B is the width of the conventionally rolled strip; C1 and C2 are the minimum and maximum values ​​of the secondary crown adjustment range of the work roll, respectively; s m This is the position of maximum forward roll movement of the work roll.

[0020] The roller compensation curve based on the "mountain" shaped cross-section is composed of segmented superpositions of compensation functions for the edge adjustment zone, the rib adjustment zone, and other positions outside the adjustment zone, with smooth connections between each region. The formula for calculating the ordinate of the roller compensation curve is as follows:

[0021]

[0022] Where x is the lateral coordinate with the left end of the work roller as the origin;

[0023] A1 is the correction amount for the edge adjustment area, and A2 and A3 are the correction amounts for the rib adjustment area;

[0024] w1 is the angular velocity of the edge adjustment zone, and w2 and w3 are the angular velocities of the rib adjustment zone;

[0025] f1-f5 is the phase of the cosine compensation function;

[0026] x1 is the center of the edge adjustment zone, and e is the width of the work roll's lateral correction of the strip edge.

[0027] x2 is the boundary between the edge adjustment zone and the rib adjustment zone;

[0028] x3 is the center position of the left quarter wave of the strip.

[0029] The center position x3 of the left quarter wave is determined based on the width of the conventionally rolled strip.

[0030] The working roll determines the transverse correction width e of the strip edge, the boundary position x2 between the edge adjustment zone and the rib adjustment zone, and the correction amounts A1 and A2 and A3 of the edge adjustment zone and the rib adjustment zone based on the characteristics of the mountain-shaped cross-section.

[0031] The method for designing the roll shape of the variable crown work roll includes the following steps:

[0032] S1: Design the cosine compensation curve for the edge adjustment zone;

[0033] S2: Cosine compensation curve of the rib adjustment zone between the center of the quarter wave position of the design strip and the boundary of the edge adjustment zone;

[0034] S3: Design the cosine compensation curve of the rib adjustment zone between the center of the quarter wave position of the strip and the center line of the roll.

[0035] Specifically, S1 is:

[0036] The preset working roll provides a lateral correction width of e for the strip edge, and the preset edge adjustment zone correction amount is A1.

[0037] The cosine compensation function for the adjustment zone on the left side of the work roll centerline is:

[0038]

[0039] T1 = 2e

[0040] w1=2π / T1

[0041] f1 = π(1 - (LB) / T1);

[0042] Among them, y edge1 (x) is the cosine compensation function for the adjustment zone on the left side of the work roll centerline; T1 is the compensation function y edge1 The period of (x); f1 is the cosine compensation function y edge1 The phase of (x);

[0043] The formula for the cosine compensation function of the adjustment zone on the right side of the work roll centerline is:

[0044]

[0045] f5 = π(1-(L+B) / T1);

[0046] Among them, y edge2 (x) is the cosine compensation function for the right-side adjustment zone of the work roll centerline; f5 is the cosine compensation function y edge2 The phase of (x);

[0047] The adjustment zone on the left side of the work roll centerline is centered on the left side of the strip. The compensation function on the right side of the centerline is used to increase the strip edge compression, and the compensation function on the left side of the centerline is used to connect with other areas on the left side of the work roll besides the adjustment zone. The adjustment zone on the right side of the work roll centerline is centered on the right side of the strip. The compensation function on the left side of the centerline is used to increase the strip edge compression, and the compensation function on the right side of the centerline is used to connect with other areas on the right side of the work roll besides the adjustment zone. The smoothing conditions for the cosine compensation function curves of the adjustment zone on the left and right sides of the work roll centerline are as follows:

[0048] y edge1 (x1-e)=0

[0049] x1 = (LB) / 2

[0050] y edge2 ((L+B) / 2-e)=0

[0051] y edge1 '(x1-e)=0

[0052] y edge2 '((L+B) / 2-e)=0

[0053] Among them, y edge1 ',y edge2 ' are the derivatives of the corresponding functions.

[0054] Specifically, S2 is:

[0055] The preset correction amount for the rib adjustment zone between the center of the quarter wave position of the strip and the boundary of the edge adjustment zone is A2, and the preset center of the left quarter wave position of the strip is x3;

[0056] The cosine compensation function for the rib adjustment zone located between the right boundary of the left side adjustment zone of the work roll and the center of the left side rib wave position of the work roll is:

[0057]

[0058] x3 = L / 2 - Q

[0059] x2=(LB) / 2+e

[0060] T2 = 2(x3 - x2) = 2(B / 2 - Qe)

[0061] w2=2π / T2

[0062] f2 = π(1 - (L - B + 2e) / T2);

[0063] Among them, y quarter1 (x) is the cosine compensation function for the rib adjustment zone located between the right boundary of the left side adjustment zone of the work roll and the center of the left quarter wave position of the work roll; Q is the length of the strip rib wave center position from the center line of the work roll; T2 is the compensation function y quarter1 The period of (x), f2 is the cosine compensation function y quarter1 The phase of (x);

[0064] The cosine compensation function for the rib adjustment zone located between the center of the right quarter wave position of the work roll and the left boundary of the right side adjustment zone of the work roll is:

[0065]

[0066] f4 = -w2(L / 2 + Q);

[0067] Among them, y quarter2 (x) is the cosine compensation function for the rib adjustment zone located between the center of the right rib wave position on the right side of the work roll and the left boundary of the right side adjustment zone on the right side of the work roll; f4 is the cosine compensation function y quarter2 The phase of (x);

[0068] The smooth connection condition between the rib adjustment zone function and the edge adjustment zone function is:

[0069] y edge1 (x2)=y quarter1 (x2)

[0070] y edge2 (L-x2)=y quarter2 (L-x2)

[0071] y edge1 '(x2)=y quarter1 '(x2)=0

[0072] y edge2 '(x2)=y quarter2 '(x2)=0

[0073] Among them, y edge1(x2) is the value of the cosine compensation function of the left side adjustment zone of the work roll centerline at the junction of the side adjustment zone and the rib adjustment zone;

[0074] y quarter1 (x2) is the value of the cosine compensation function of the left rib adjustment area of ​​the work roll centerline at the junction of the edge adjustment area and the rib adjustment area;

[0075] y edge2 (L-x2) is the value of the cosine compensation function of the right side adjustment zone of the work roll centerline at the left boundary position;

[0076] y quarter2 (L-x2) is the value of the cosine compensation function of the right-side rib adjustment zone of the work roll centerline at the right boundary position;

[0077] y edge1 ',y edge2 ',y quarter1 ',y quarter2 ' are the derivatives of the corresponding functions.

[0078] Specifically, S3 is:

[0079] The preset compensation correction amount for the rib adjustment zone between the center of the quarter wave position of the strip and the center line of the work roll is A3.

[0080] The formula for the compensation function of the rib adjustment zone between the center of the quarter wave of the strip and the center line of the work roll is:

[0081]

[0082] T3 = 2Q

[0083] w3=2π / T3

[0084] f3=π(1-L / T3)

[0085] Among them, y quarter3 (x) is the compensation function for the rib adjustment zone between the center of the quarter wave position of the strip and the center line of the work roll; T3 is the compensation function y quarter3 The period of (x), f3 is the cosine compensation function y quarter3 The phase of (x);

[0086] The smooth connection condition for the cosine compensation curve of the rib adjustment zone between the center of the quarter wave position of the strip and the boundary of the edge adjustment zone and the cosine compensation curve of the rib adjustment zone between the center of the quarter wave position of the strip and the center line of the work roll is as follows:

[0087] y quarter1 (x3)=y quarter3 (x3)

[0088] y quarter2 (L-x3)=y quarter3 (L-x3)

[0089] y quarter1 '(x3)=y quarter3 '(x3)=0

[0090] y quarter2 '(L-x3)=y quarter3 '(L-x3)=0

[0091] Among them, y quarter1 (x3) is the value of the cosine compensation function of the adjustment zone on the left side of the work roll centerline at the center position of the left quarter wave of the strip;

[0092] y quarter3 (x3) is the value of the rib adjustment zone compensation function between the center of the strip quarter wave position and the center line of the work roll at the center position of the left quarter wave of the strip;

[0093] y quarter2 (L-x3) is the value of the cosine compensation function of the rib adjustment area located between the center of the right quarter wave position of the work roll and the left boundary position of the right side adjustment area of ​​the work roll at the center of the right quarter wave position of the work roll.

[0094] y quarter3 (L-x3) is the value of the compensation function for the rib adjustment zone between the center of the quarter wave position of the strip and the center line of the work roll at the center of the right quarter wave position of the strip.

[0095] y quarter1 ',y quarter2 ',y quarter3 ' are the derivatives of the corresponding functions.

[0096] Compared with the prior art, the beneficial effects of the technical solution of the present invention are:

[0097] The aforementioned variable-convexity work roll, designed to improve the "mountain"-shaped cross-section of strip steel, eliminates the "mountain"-shaped cross-section defect during hot rolling by increasing the pressure on the strip's edges and reducing the pressure on its ribs. Once the roll shape design is complete, it can be ground at discrete points using a grinding machine.

[0098] The aforementioned design method for variable crown work rolls to improve the "mountain"-shaped cross-section of strip steel is based on dividing the strip's normal rolling width into edge and center adjustment zones. It designs regional compensation curves using piecewise functions and smooths the curves to adjust the roll's reduction distribution on the strip. This design method allows for selection of the normal rolling strip width, the location of the quarter-wave, and the transverse correction width at the strip's edge, based on actual site conditions. It is highly feasible and cost-effective for implementation on rolling mills. Practice has proven that the variable crown work rolls for improving the "mountain"-shaped cross-section of strip steel provided by this invention can significantly improve the problem of "mountain"-shaped cross-section defects in strip steel. Attached Figure Description

[0099] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0100] Figure 1 These are the roller shape design curve and compensation function curve in the embodiments of the present invention;

[0101] Figure 2 This is a schematic diagram of the "mountain" shaped cross-section of the strip steel provided in an embodiment of the present invention;

[0102] Figure 3 This is an actual diagram of the "mountain" shaped cross-section of the strip steel provided in an embodiment of the present invention. Detailed Implementation

[0103] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0104] This invention provides a variable convexity work roll for improving the mountain-shaped cross-section of strip steel and its roll shape design method.

[0105] like Figure 1 The working roll shape of the present invention is formed by superimposing a cubic curve and a roll body compensation curve based on a mountain-shaped cross section. The roll body compensation curve is formed by superimposing the compensation function of the edge adjustment area, the compensation function of the rib adjustment area, and the compensation function of other positions outside the adjustment area in segments, and the connection between each area is smooth.

[0106] The formula for calculating the ordinate of the work roll profile is as follows:

[0107] y0(x)=a1x+a2x 2 +a3x 3

[0108] y(x) = y0(x) + y1(x)

[0109] Where y0(x) is a cubic curve function, and a1, a2, a3 are the coefficients of the cubic curve polynomial;

[0110] y(x) is the curve function of the working roll shape designed in this invention;

[0111] y1(x) is the roller body compensation curve function;

[0112] The calculation process for a1, a2, and a3 is as follows:

[0113] a1 = -a2L - 3a3(L / 2) 2 -a3B 2 / 4

[0114]

[0115]

[0116] Where L is the length of the work roll body; B is the width of the conventionally rolled strip; C1 and C2 are the minimum and maximum values ​​of the secondary crown adjustment range of the work roll, respectively; s m This is the position of maximum forward roll movement of the work roll.

[0117] The formula for calculating the ordinate of the roller body compensation curve is:

[0118]

[0119] Where x is the lateral coordinate with the left end of the work roller as the origin;

[0120] A1 is the correction amount for the edge adjustment area, and A2 and A3 are the correction amounts for the rib adjustment area;

[0121] w1 is the angular velocity of the edge adjustment zone, and w2 and w3 are the angular velocities of the rib adjustment zone;

[0122] f1-f5 is the phase of the cosine compensation function;

[0123] x1 is the center of the edge adjustment zone, and e is the width of the work roll's lateral correction of the strip edge.

[0124] x2 is the boundary between the edge adjustment zone and the rib adjustment zone;

[0125] x3 is the center position of the left quarter wave of the strip.

[0126] Determine the center position of the left quarter wave based on the width of the normally rolled strip; according to... Figure 2 as well as Figure 3 The "mountain" shaped cross-sectional features shown determine the transverse correction width of the strip edge, the position of the edge adjustment zone and the rib adjustment zone, and the correction values ​​of the edge adjustment zone and the rib adjustment zone.

[0127] The variable convexity work roll shape for improving the "mountain" shaped cross-section of strip steel in this embodiment has an edge adjustment zone, a middle adjustment zone, and other areas outside the adjustment zones. The work roll shape is designed based on the "mountain" shaped cross-section characteristics, and the "mountain" shaped cross-section defect of strip steel can be significantly improved by increasing the edge pressing and reducing the rib pressing.

[0128] Furthermore, the roll shape design method for the variable crown work roll of the present invention can be used to eliminate the "mountain" shaped cross-section defect of strip steel. This roll shape design method is applicable to rolling mills that cannot use reciprocating equidistant circulating rolls. By superimposing cubic curves and roll compensation curves, the rolls are made capable of adjusting the "mountain" shaped cross-section. The specific steps are as follows:

[0129] S1: Design the cosine compensation curve for the edge adjustment zone;

[0130] S2: Cosine compensation curve of the rib adjustment zone between the center of the quarter wave position of the design strip and the boundary of the edge adjustment zone;

[0131] S3: Design the cosine compensation curve of the rib adjustment zone between the center of the quarter wave position of the strip and the center line of the roll.

[0132] S1 specifically refers to:

[0133] The preset working roll provides a lateral correction width of e for the strip edge, and the preset edge adjustment zone correction amount is A1.

[0134] The cosine compensation function for the adjustment zone on the left side of the work roll centerline is:

[0135]

[0136] T1 = 2e

[0137] w1=2π / T1

[0138] f1 = π(1 - (LB) / T1);

[0139] Among them, y edge1 (x) represents the cosine compensation function of the adjustment zone on the left side of the work roll centerline; w1 represents the angular velocity of the adjustment zone function; L represents the length of the work roll body; B represents the width of the conventionally rolled strip; T1 represents the compensation function y. edge1 The period of (x); f1 is the cosine compensation function y edge1 The phase of (x);

[0140] The formula for the cosine compensation function of the adjustment zone on the right side of the work roll centerline is:

[0141]

[0142] f5 = π(1-(L+B) / T1);

[0143] Among them, y edge2 (x) is the cosine compensation function for the right-side adjustment zone of the work roll centerline; f5 is the cosine compensation function y edge2 The phase of (x);

[0144] The smoothing conditions for the cosine compensation function curves of the left side adjustment zone and the right side adjustment zone of the work roll centerline are as follows:

[0145] y edge1 (x1-e)=0

[0146] x1 = (LB) / 2

[0147] y edge2 ((L+B) / 2-e)=0

[0148] y edge1 '(x1-e)=0

[0149] y edge2 '((L+B) / 2-e)=0

[0150] Where x1 is the center of the edge adjustment zone, y edge1 ',y edge2 ' are the derivatives of the corresponding functions.

[0151] S2 specifically refers to:

[0152] The preset correction amount for the rib adjustment zone between the center of the quarter wave position of the strip and the boundary of the edge adjustment zone is A2, and the preset center of the left quarter wave position of the strip is x3;

[0153] The cosine compensation function for the rib adjustment zone located between the right boundary of the left side adjustment zone of the work roll and the center of the left side rib wave position of the work roll is:

[0154]

[0155] x3 = L / 2 - Q

[0156] x2=(LB) / 2+e

[0157] T2 = 2(x3 - x2) = 2(B / 2 - Qe)

[0158] w2=2π / T2

[0159] f2 = π(1 - (L - B + 2e) / T2);

[0160] Among them, y quarter1(x) represents the cosine compensation function of the rib adjustment zone located between the right boundary of the left side adjustment zone of the work roll and the center of the left quarter wave position of the work roll; w2 represents the angular velocity of the corresponding rib adjustment zone function; x3 represents the center position of the left quarter wave of the strip; L represents the length of the work roll body; B represents the width of the conventionally rolled strip; x2 represents the boundary position between the left side adjustment zone and the rib adjustment zone on the center line of the work roll; e represents the lateral correction width of the strip edge by the work roll; Q represents the length of the strip rib wave center position from the center line of the work roll; T2 represents the compensation function y quarter1 The period of (x), f2 is the cosine compensation function y quarter1 The phase of (x);

[0161] The cosine compensation function for the rib adjustment zone located between the center of the right quarter wave position of the work roll and the left boundary of the right side adjustment zone of the work roll is:

[0162]

[0163] f4 = -w2(L / 2 + Q);

[0164] Among them, y quarter2 (x) is the cosine compensation function for the rib adjustment zone located between the center of the right rib wave position on the right side of the work roll and the left boundary of the right side adjustment zone on the right side of the work roll; f4 is the cosine compensation function y quarter2 The phase of (x);

[0165] The smooth connection condition between the rib adjustment zone function and the edge adjustment zone function is:

[0166] y edge1 (x2)=y quarter1 (x2)

[0167] y edge2 (L-x2)=y quarter2 (L-x2)

[0168] y edge1 '(x2)=y quarter1 '(x2)=0

[0169] y edge2 '(x2)=y quarter2 '(x2)=0

[0170] Among them, y edge1 (x2) is the value of the cosine compensation function of the left side adjustment zone of the work roll centerline at the junction of the side adjustment zone and the rib adjustment zone;

[0171] y quarter1 (x2) is the value of the cosine compensation function of the left rib adjustment area of ​​the work roll centerline at the junction of the edge adjustment area and the rib adjustment area;

[0172] y edge2 (L-x2) is the value of the cosine compensation function of the right side adjustment zone of the work roll centerline at the left boundary position;

[0173] y quarter2 (L-x2) is the value of the cosine compensation function of the right-side rib adjustment zone of the work roll centerline at the right boundary position;

[0174] y edge1 ',y edge2 ',y quarter1 ',y quarter2 ' are the derivatives of the corresponding functions.

[0175] S3 specifically refers to:

[0176] The preset compensation correction amount for the rib adjustment zone between the center of the quarter wave position of the strip and the center line of the work roll is A3.

[0177] The formula for the compensation function of the rib adjustment zone between the center of the quarter wave of the strip and the center line of the work roll is:

[0178]

[0179] T3 = 2Q

[0180] w3=2π / T3

[0181] f3=π(1-L / T3)

[0182] Among them, y quarter3 (x) is the compensation function for the rib adjustment zone between the center of the quarter wave of the strip and the center line of the work roll; w3 is the angular velocity of the corresponding rib adjustment zone function; T3 is the compensation function y quarter3 The period of (x), f3 is the cosine compensation function y quarter3 (x) is the phase; Q is the distance from the center of the strip rib to the center line of the work roll; L is the length of the work roll body;

[0183] The smooth connection condition for the cosine compensation curve of the rib adjustment zone between the center of the quarter wave position of the strip and the boundary of the edge adjustment zone and the cosine compensation curve of the rib adjustment zone between the center of the quarter wave position of the strip and the center line of the work roll is as follows:

[0184] y quarter1 (x3)=y quarter3 (x3)

[0185] y quarter2 (L-x3)=y quarter3 (L-x3)

[0186] y quarter1 '(x3)=yquarter3 '(x3)=0

[0187] y quarter2 '(L-x3)=y quarter3 '(L-x3)=0

[0188] Among them, y quarter1 (x3) is the value of the cosine compensation function of the adjustment zone on the left side of the work roll centerline at the center position of the left quarter wave of the strip;

[0189] y quarter3 (x3) is the value of the rib adjustment zone compensation function between the center of the strip quarter wave position and the center line of the work roll at the center position of the left quarter wave of the strip;

[0190] y quarter2 (L-x3) is the value of the cosine compensation function of the rib adjustment area located between the center of the right quarter wave position of the work roll and the left boundary position of the right side adjustment area of ​​the work roll at the center of the right quarter wave position of the work roll.

[0191] y quarter3 (L-x3) is the value of the compensation function for the rib adjustment zone between the center of the quarter wave position of the strip and the center line of the work roll at the center of the right quarter wave position of the strip.

[0192] y quarter1 ',y quarter2 ',y quarter3 ' are the derivatives of the corresponding functions.

[0193] The following description, in conjunction with specific embodiments, illustrates this point.

[0194] A hot-rolled coil production line in a certain factory uses a CVC mill for its finishing mill stand. The work roll body length is 2550mm, and the main rolling specification is 1600mm wide strip. The secondary crown adjustment range of the rolls (i.e., work rolls) is [-0.4mm, 0.7mm]. The maximum forward roll shift position is 150mm, and the location of the strip quarter wave is 400mm from the roll centerline. Due to the relatively wide mill, the following issues are prone to occur during the rolling process: Figure 3 The outline of the "mountain" shaped cross-section is shown.

[0195] Step 1: Determine the cubic curve function of the roll.

[0196] The cubic curve function is:

[0197] y0(x)=a1x+a2x 2 +a3x 3

[0198] a1 = -a2L - 3a3(L / 2) 2 -a3B2 / 4

[0199]

[0200]

[0201] Among them, the roll body length L = 2550mm; the width of the normally rolled strip B = 1600mm; the minimum value of the roll secondary crown adjustment range C1 = -0.4mm; the maximum value of the roll secondary crown adjustment range C2 = 0.7mm; and the maximum forward roll shift position s. m =150mm. Calculated according to the above formula:

[0202] a1 = 1.45503e-03

[0203] a2 = -1.39177e-06

[0204] a3 = 3.75924e-10

[0205] Step Two: Based on the "mountain"-shaped cross-sectional outline diagram at the site, divide the area into edge adjustment zones and rib adjustment zones. For example... Figure 1 As shown, with the left side of the roll as the zero point of the lateral position, the center of the adjustment area on the left side of the roll centerline is located at the left side of the strip, i.e., x1 = 475mm. The lateral correction width of the roll edge is set to e = 200mm, meaning the position of the adjustment area on the left side of the roll centerline is [275mm, 675mm], i.e., x2 = 675mm. Similarly, the position of the adjustment area on the right side of the roll centerline is [1875mm, 2275mm].

[0206] The center of the quarter wave of the strip is 400mm from the center line of the roll, i.e., Q = 400mm, x3 = 875mm. The adjustment zone of the strip rib is located at [675mm, 1875mm].

[0207] Step 3: Design the compensation curve. In step S1, the preset transverse correction width of the roll for the strip edge is e = 200 mm, and the compensation value of the edge adjustment zone is A1 = 6 μm.

[0208] The formula for the cosine compensation function of the adjustment zone on the left side of the roll centerline is:

[0209]

[0210] T1 = 2e

[0211] w1=2π / T1

[0212] f1 = π(1 - (LB) / T1);

[0213] Among them, the period T1 = 400mm, the phase f1 = -(11 / 8)π, the angular velocity w1 = 2π / 400, the roll body length L = 2550mm, and the width of the conventional strip steel B = 1600mm.

[0214] The formula for the cosine compensation function of the adjustment zone on the right side of the roll centerline is:

[0215]

[0216] f5 = π(1-(L+B) / T1);

[0217] The phase of the cosine compensation function is f5 = -(75 / 8)π.

[0218] The smoothing conditions for the compensation curves of the edge adjustment zone and the rib adjustment zone are as follows:

[0219] y edge1 (275)=0

[0220] y edge1 '(275)=0

[0221] y edge2 (2275)=0

[0222] y edge2 '(2275)=0

[0223] In step S2, the compensation value A2 for this area is preset to 12 μm, and the center position of the left quarter wave of the strip is x3 = 875 mm.

[0224] The cosine compensation function for the rib adjustment zone located between the right boundary of the left side adjustment zone of the work roll and the center of the left side rib wave position of the work roll is:

[0225]

[0226] x3 = L / 2 - Q

[0227] x2=(LB) / 2+e

[0228] T2 = 2(x3 - x2) = 2(B / 2 - Qe)

[0229] w2=2π / T2

[0230] f2 = π(1 - (L - B + 2e) / T2);

[0231] Among them, the intersection position of the left side adjustment area and the rib adjustment area of ​​the roll centerline is x2=675mm; the length of the strip rib wave center position from the roll centerline is Q=400mm; the period of the compensation function is T2=400mm, the angular velocity is w2=2π / 400, and the phase of the cosine compensation function is f2=-(19 / 8)π.

[0232] The cosine compensation function for the rib adjustment zone located between the center of the right quarter wave position of the work roll and the left boundary of the right side adjustment zone of the work roll is:

[0233]

[0234] f4 = -w2(L / 2 + Q);

[0235] The phase of the cosine compensation function is f4 = -(67 / 8)π.

[0236] The smooth connection condition between the rib adjustment zone function and the edge adjustment zone function is:

[0237] y edge1 (675)=y quarter1 (675)

[0238] y edge2 (1875)=y quarter2 (1875)

[0239] y edge1 '(675)=y quarter1 '(675)=0

[0240] y edge2 '(1875)=y quarter2 '(1875)=0

[0241] Among them, y edge1 ',y edge2 ',y quarter1 ',y quarter2 ' are the derivatives of the corresponding functions.

[0242] In step S3, the preset compensation value for this area is A3 = 12 μm, and the compensation function formula is:

[0243]

[0244] T3 = 2Q

[0245] w3=2π / T3

[0246] f3=π(1-L / T3)

[0247] The period of the compensation function is T3 = 800 mm, the angular velocity is w3 = 2π / 800, and the phase of the cosine compensation function is f3 = -(35 / 16)π.

[0248] The smooth connection condition for the cosine compensation curve of the rib adjustment zone between the center of the strip quarter wave position and the boundary of the edge adjustment zone and the cosine compensation curve of the rib adjustment zone between the center of the strip quarter wave position and the roll centerline is as follows:

[0249] y quarter1 (875)=y quarter3 (875)

[0250] y quarter2 (1675)=y quarter3 (1675)

[0251] y quarter1 '(875)=y quarter3 '(875)=0

[0252] y quarter2 '(1675)=y quarter3 '(1675)=0

[0253] Among them, y quarter3 ' represents the derivative of the corresponding function.

[0254] Step 4: Overlay the compensation curve and the cubic curve.

[0255] The final roll shape in this embodiment is:

[0256]

[0257] The present invention provides a roll shape design method for a variable convexity work roll to improve the "mountain" shaped cross-section of strip steel. By adjusting the set parameters to increase the reduction at the edge of the strip and the reduction at the rib of the strip, the "mountain" shaped cross-section defect of the strip is eliminated. After the roll shape design is completed, it can be ground on a grinding machine in a discrete point manner.

[0258] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A cambered work roll for improving the camber profile of a strip steel, characterized in that The work roll contour is formed by superimposing a cubic curve and a roll body compensation curve based on a cambered section, the roll body compensation curve is formed by superimposing a side adjustment area compensation function, a rib adjustment area compensation function and a compensation function at other positions outside the adjustment area in sections, and each area is connected smoothly; The work roll contour longitudinal coordinate calculation formula is: y(x) = y0(x) + y1(x) Wherein, y(x) is the work roll contour curve function; y0(x) is a cubic curve function, and y1(x) is a roll body compensation curve function; The roll body compensation curve longitudinal coordinate calculation formula is: Wherein, x is a transverse coordinate with the left end of the work roll as the origin; A1 is a side adjustment area correction amount, A2 and A3 are rib adjustment area correction amounts; w1 is a side adjustment area function angular velocity, w2 and w3 are rib adjustment area function angular velocities; f1-f5 are cosine compensation function phases; x1 is a side adjustment area center, and e is a work roll transverse correction width for the strip side; x2 is a side adjustment area and rib adjustment area boundary position; x3 is a left quarter wave center position of the strip.

2. The crown reducing work roll for improving the camber of a strip steel as claimed in claim 1, wherein The cubic curve function is: y0(x) = a1x + a2x + a3x 2 3 ​ Wherein, a1, a2 and a3 are cubic curve polynomial coefficients; The calculation process of a1, a2 and a3 is: a1 = -a2L - 3a3(L / 2) 2 -a3B 2 / 4 Wherein, L is the length of the work roll body, mm; B is the width of the strip, mm; C1 and C2 are the minimum and maximum values of the work roll secondary crown adjustment range, mm; s m is the positive maximum roll shift position of the work roll, mm.

3. The cambering work roll for improving the camber of a strip steel profile according to claim 1, characterized in that, The left quarter wave center position x3 is determined according to the width of the conventional rolling strip; The work roll transverse correction width e for the strip side, the side adjustment area and rib adjustment area boundary position x2, and the side adjustment area correction amount A1 and the rib adjustment area correction amounts A2 and A3 are determined according to the cambered section characteristics.

4. The roll contour design method for work rolls to improve camber of strip edge in a strip edge cambering operation according to claim 1, characterized in that, The method comprises the following steps: S1: design a cosine compensation curve for the side adjustment area; S2: design a cosine compensation curve for the rib adjustment area between the strip quarter wave center and the side adjustment area boundary; S3: design a cosine compensation curve for the rib adjustment area between the strip quarter wave center and the roll center line; The S1 is specifically: A preset work roll transverse correction width for the strip side is e, and a preset side adjustment area correction amount is A1; The cosine compensation function of the left side adjustment area of the work roll center line is: T1 = 2e w1 = 2π / T1 f1 = π(1-(L-B) / T1); wherein y edge1 (x) is a cosine compensation function for the left side of the work roll center line; w1 is the angular velocity of the side adjustment zone function; L is the length of the work roll barrel; B is the width of the strip; T1 is the period of the compensation function y edge1 (x); and f1 is the phase of the cosine compensation function y edge1 (x). The cosine compensation function formula of the right side adjustment area of the work roll center line is: f5 = π(1-(L+B) / T1); where y edge2 (x) is a cosine compensation function for the right side edge adjustment area of the work roll center line; f5 is the phase of the cosine compensation function y edge2 (x).

5. The roll contour design method of the variable crown work roll for improving the cambered section of the strip according to claim 4, characterized in that The cosine compensation function curve of the left side adjustment area of the work roll center line and the cosine compensation function smooth condition of the right side adjustment area of the work roll center line are: y edge1 (x1-e) = 0 x1 = (L-B) / 2 y edge2 ((L+B) / 2-e) = 0 y edge1 '(x1-e) = 0 y edge2 '((L+B) / 2-e) = 0 Where x1 is the center of the edge adjustment zone, y edge1 ',y edge2 ' are the derivatives of the corresponding functions.

6. The roll contour design method for work rolls to improve camber of strip edge in a strip edge cambering operation according to claim 4, characterized in that, The S2 is specifically: A preset rib adjustment area correction amount between the strip quarter wave center and the side adjustment area boundary is A2, and a preset strip left quarter wave center is x3; The cosine compensation function of the rib adjustment area between the right boundary position of the left side adjustment area of the work roll and the left rib wave center of the work roll is: x3 = L / 2-Q x2 = (L-B) / 2+e T2 = 2(x3-x2) = 2(B / 2-Q-e) w2 = 2π / T2 f2 = π(1-(L-B+2e) / T2); wherein y quarter1 (x) is a cosine compensation function of the rib adjustment zone between the right boundary position of the left side edge adjustment zone of the work roll and the center of the left side quarter wave position of the work roll; w2 is the angular velocity corresponding to the rib adjustment zone function; x3 is the center position of the left side quarter wave of the strip; L is the length of the work roll body; B is the width of the continuously rolled strip; x2 is the position of the intersection of the left side edge adjustment zone of the work roll center line and the rib adjustment zone; e is the lateral correction width of the work roll to the edge of the strip; Q is the length of the rib wave center position of the strip from the work roll center line; T2 is the period of the compensation function y quarter1 (x); f2 is the phase of the cosine compensation function y quarter1 (x). The cosine compensation function of the rib adjusting area between the center of the right quarter wave position of the work roll and the left boundary position of the edge adjusting area on the right side of the work roll is: f4=-w2(L / 2+Q); where y quarter2 (x) is a cosine compensation function of the rib adjustment area between the center of the rib wave position on the right side of the work roll and the left boundary position of the right side edge adjustment area of the work roll; f4 is the phase of the cosine compensation function y quarter2 (x). The smooth connection condition of the rib adjusting area function and the edge adjusting area function is: y edge1 (x2) = y quarter1 (x2) y edge2 (L-x2) = y quarter2 (L-x2) y edge1 '(x2) = y quarter1 '(x2) = 0 y edge2 '(x2) = y quarter2 '(x2) = 0 wherein y edge1 (x2) is the value of the cosine compensation function for the edge adjustment region on the left side of the work roll center line at the position where the edge adjustment region and the rib adjustment region meet. y quarter1 (x2) is the value of the cosine compensation function of the left rib adjustment area of the work roll center line at the junction of the edge adjustment area and the rib adjustment area; y edge2 (L - x2) is the value of the cosine compensation function of the right edge adjustment zone of the work roll center line at the left boundary position; y quarter2 (L - x2) is the value of the cosine compensation function of the right rib adjustment area of the work roll center line at the right boundary position; y edge1 ', y edge2 ', y quarter1 ', y quarter2 ' are the derivatives of the corresponding functions, respectively.

7. The roll contour design method for work rolls to improve camber of strip edge in a strip edge cambering operation according to claim 4, characterized in that, The S3 is specifically: The compensation correction amount of the rib adjusting area between the center of the preset quarter wave position of the strip steel and the center line of the work roll is A3, The compensation function formula of the rib adjusting area between the center of the quarter wave position of the strip steel and the center line of the work roll is: T3=2Q w3=2π / T3 f3=π(1-L / T3) wherein y quarter3 (x) is a rib adjustment zone compensation function between the strip quarter wave position center and the work roll center line; w3 is the angular velocity corresponding to the rib adjustment zone function; T3 is the period of the compensation function y quarter3 (x); f3 is the phase of the cosine compensation function y quarter3 (x); Q is the length of the strip rib wave center position from the work roll center line; L is the work roll body length; The smooth connection condition of the cosine compensation curve of the rib adjusting area between the center of the quarter wave position of the strip steel and the boundary of the edge adjusting area and the cosine compensation curve of the rib adjusting area between the center of the quarter wave position of the strip steel and the center line of the work roll is: y quarter1 (x3) = y quarter3 (x3) y quarter2 (L-x3) = y quarter3 (L-x3) y quarter1 '(x3) = y quarter3 '(x3) = 0 y quarter2 '(L-x3) = y quarter3 '(L-x3) = 0 where y quarter1 (x3) is the value of the cosine compensation function for the rib adjustment zone on the left side of the work roll center line at the center of the left-side quarter wave of the strip steel; y quarter3 (x3) is the value of the rib adjustment zone compensation function between the center of the strip quarter wave position and the center line of the work roll at the left side quarter wave center position of the strip; y quarter2 (L - x3) is the value of the rib adjustment zone cosine compensation function at the center of the right-hand quarter wave position of the work roll between the center of the right-hand quarter wave position of the work roll and the left boundary position of the right-hand edge adjustment zone of the work roll; y quarter3 (L - x3) is the value of the rib adjustment zone compensation function between the strip quarter wave position center and the work roll center line at the strip right side strip quarter wave position center; y quarter1 ', y quarter2 ', y quarter3 ' are the derivatives of the corresponding functions.

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