Slip control method before and after a finishing mill train

Abstract

The application discloses a front and rear slip control method for a finishing mill set, and relates to the field of rolling mill control technology.The method comprises the following steps: processing the reduction rates of each stand corresponding to the strip to be finished rolling, so as to obtain the influence coefficient of the reduction rate on the front slip; processing the entry thickness and the roll diameter of each stand corresponding to the strip to be finished rolling, so as to obtain the influence coefficient of the roll diameter on the front slip; processing the influence coefficient of the reduction rate on the front slip and the influence coefficient of the roll diameter on the front slip, so as to obtain the front slip coefficient of each stand; processing the front slip coefficient of each stand, so as to obtain the rear slip coefficient of each stand; processing the exit speed of the last stand of the finishing mill, the front slip coefficient and the rear slip coefficient of each stand, so as to obtain the speed of each stand; correcting the rear slip coefficient of the first stand of the finishing mill; processing the corrected rear slip coefficient of the first stand of the finishing mill, so as to obtain the entry speed of the first stand of the finishing mill and the front roller way speed of the finishing mill.The application can improve the rolling stability between stands and avoid the occurrence of the waist collapse phenomenon of soft material steel in front of the finishing mill.

Description

Technical Field

[0001] The present invention relates to the technical field of steel rolling, and in particular to a forward and backward sliding control method of a finishing mill group. Background Art

[0002] refer to Figure 1 The existing 1549mm hot rolling production line includes a furnace area, a roughing area, a finishing area, a laminar cooling area and a coiling area arranged in sequence. The furnace area includes four heating furnaces arranged in sequence. The roughing area includes a high-pressure water descaling box, a roughing vertical roll mill (VE0), a roughing flat roll mill (R0) and an insulation cover arranged in sequence. The finishing area includes a rotary drum shear, a 7-stand finishing mill (F0~F6 stands), a convexity meter and a flatness meter, as well as a width gauge and a thickness gauge arranged in sequence. The laminar cooling area is equipped with laminar cooling equipment. The coiling area is equipped with two coilers (C1, C2). The main production process of the 1549mm hot rolling production line is that the slab is first heated in a heating furnace according to the temperature specified by the process, and then enters the roughing mill for rolling after being heated to the target temperature. The roughing vertical roll controls the width, and the roughing flat roll controls the thickness. Reversible rolling is performed in the roughing mill, generally for 5 to 7 passes; after rolling in the roughing mill, the strip reaches the preset target thickness, width and temperature, and then enters the finishing mill for seven-stand flat roll continuous rolling to achieve the preset target thickness, temperature, convexity and flatness; the strip is then controlled by laminar cooling to reach the target coiling temperature; finally, the strip is formed into a coil by a coiler.

[0003] The finishing mill adopts seven-stand continuous rolling. During the seven-stand continuous rolling process, ensuring the equal second flow rate between each stand is the most basic and critical link for stable continuous rolling. Only when the second flow rate between each stand is equal can the flow between stands be stable and the rolling accuracy can meet the requirements.

[0004] In a seven-stand continuous rolling process, equal flow rate per second between stands means the same cross-sectional strip flow rate per unit time. The specific formula for calculating flow rate per second is flow rate per second = thickness * width * speed. Since the widths of the stands of the finishing mill are approximately equal, equal flow rate per second between stands can be achieved when the stand entrance thickness, exit thickness, stand entrance speed, and stand exit speed meet the following relationship:

[0005] then(i)*v en (i)=then(i+1)*v ex (i)=then(i+1)*v en (i+1)=then(i+2)*v ex (i+1);

[0006] Where i represents the rack number, then(i) represents the inlet thickness of the i-th rack, v en (i) represents the inlet velocity of the i-th rack, then (i+1) represents the inlet thickness of the i+1-th rack, v ex (i) represents the outlet speed of the i-th rack, v en (i+1) represents the inlet velocity of the i+1th rack, then (i+2) represents the inlet thickness of the i+2th rack, v ex (i+1) represents the exit speed of the i-th rack.

[0007] Since the temperature drop between the outlet of the i-th rack and the inlet of the i+1-th rack is very small, it is generally believed that the outlet thickness of the i-th rack is equal to the inlet thickness of the i+1-th rack. Therefore, the outlet velocity of the i-th rack is equal to the inlet velocity of the i+1-th rack, that is, v ex (i) = v en (i+1).

[0008] In the seven-stand continuous rolling process, based on the definition of forward slip, the forward slip coefficient of the stand and the speed of the stand satisfy the following relationship:

[0009] v ex (i) = v(i) * fslip(i);

[0010] Among them, i represents the rack number, v ex (i) represents the exit speed of the ith stand, v(i) represents the rolling speed of the ith stand, and fslip(i) represents the forward slip coefficient of the ith stand.

[0011] Based on the definition of backslip, the backslip coefficient of the rack and the speed of the rack satisfy the following relationship:

[0012] v en (i) = v(i) * bslip(i);

[0013] Among them, i represents the rack number, v en (i) represents the inlet velocity of the i-th stand, v(i) represents the rolling speed of the i-th stand, and bslip(i) represents the backslip coefficient of the i-th stand.

[0014] At the same time, since the second traffic between racks is equal, then(i)*v en (i)=then(i+1)*v ex (i) Therefore, when the second flow rate between racks is equal, the forward slip coefficient and the backward slip coefficient of the rack satisfy the following relationship:

[0015] bslip(i)=then(i+1)*fslip(i) / then(i).

[0016] At present, when finishing rolling is carried out, the forward slip coefficient of each finishing stand is first determined according to the parameters of the finishing strip, and then based on the determined forward slip coefficient of each finishing stand, the predetermined outlet speed of the last finishing stand, the inlet thickness and outlet thickness of each finishing stand, calculations are performed using the relationship satisfied when the second flow rate between each stand is equal, the relationship between the forward slip coefficient of the stand and the speed of the stand, and the relationship between the backward slip coefficient of the stand and the speed of the stand to determine the inlet speed, rolling speed and outlet speed of each finishing stand.

[0017] At present, for seven-stand continuous rolling, the forward slip coefficient of each stand is given based on experience. Specifically, according to the roll diameter and the reduction rate range, the process personnel give the corresponding forward slip coefficients in different ranges. After determining the forward slip coefficient, the backward slip coefficient is determined based on the relationship between the forward slip coefficient and the backward slip coefficient when the second flow rate between each stand is equal.

[0018] However, since the accuracy of the forward and backward slip coefficients directly affects the calculation accuracy of the entry speed, rolling speed, and exit speed of each finishing mill stand, the accuracy of the forward and backward slip coefficients cannot be guaranteed when the forward and backward slip coefficients are determined using a range value method. When the forward and backward slip coefficients of each stand have large deviations, the calculated entry speed, rolling speed, and exit speed of each finishing mill stand will also have large deviations, causing a mismatch in the second flow rate between the stands. When the second flow rate between the stands does not match, it will lead to loop anomalies and even scrap steel failures. In addition, when the forward and backward slip coefficients are determined using a range value method, the characteristics of different steel grades are not taken into account. When rolling soft steel, it is easy for the soft steel to collapse between the front roller and the finishing mill unit, which in turn causes scratches on the lower surface of the strip. Summary of the Invention

[0019] In order to solve some or all of the technical problems existing in the above-mentioned prior art, the present invention provides a method for controlling forward and backward sliding of a finishing mill group.

[0020] The technical solutions of the present invention are as follows:

[0021] A method for controlling forward and backward sliding of a finishing mill is provided, the method comprising:

[0022] Using the preset first influence coefficient calculation model, the reduction ratio of each stand corresponding to the finished strip is calculated and processed to obtain the influence coefficient of the reduction ratio on the forward slip;

[0023] Using the preset second influence coefficient calculation model, the inlet thickness and roll diameter of each stand corresponding to the finished strip are calculated and processed to obtain the influence coefficient of the roll diameter on the forward slip;

[0024] Using the preset forward slip coefficient calculation model, the influence coefficients of the reduction rate and the roll diameter on the forward slip are calculated and processed to obtain the forward slip coefficients of each stand;

[0025] Using a preset relationship model between the forward slip coefficient and the backward slip coefficient, the forward slip coefficient of each rack is calculated to obtain the backward slip coefficient of each rack;

[0026] Using the preset relationship model between the forward slip coefficient and the stand speed, the relationship model between the backward slip coefficient and the stand speed, and the relationship model between the exit speed of the front stand and the entry speed of the rear stand, the exit speed of the final stand of the finishing rolling mill, the forward slip coefficient and the backward slip coefficient of each stand are calculated and processed to obtain the entry speed, rolling speed and exit speed of each stand;

[0027] Utilizing preset backslip correction coefficients for different steel grades and a preset backslip correction model for the finishing first stand, the backslip coefficient of the finishing first stand is calculated and processed to obtain a corrected backslip coefficient of the finishing first stand;

[0028] Using the preset relationship model between the backslip coefficient and the stand speed, the corrected backslip coefficient of the first stand of the finishing mill is calculated to obtain the inlet speed of the first stand of the finishing mill;

[0029] The preset relationship model between the roller speed before finishing rolling and the inlet speed of the first finishing stand is used to calculate the inlet speed of the first finishing stand to obtain the roller speed before finishing rolling.

[0030] In some optional implementations, the first influence coefficient calculation model expression is:

[0031] flsip eps (i)=((((e5*eps(i)+e4)*eps(i)+e3)*eps(i)+e2)*eps(i)+e1)*eps(i)+e0;

[0032] Among them, i represents the rack number identification, flsip eps (i) represents the influence coefficient of the reduction rate corresponding to the i-th rack on the forward slip, eps(i) represents the reduction rate of the i-th rack, and e5, e4, e3, e2, e1 and e0 represent the reduction rate coefficients.

[0033] In some optional embodiments, the reduction coefficient is set to:

[0034] Coefficient name e5 e4 e3 e2 e1 e0 Coefficient value 7.42 -10.841 4.901 -0.8848 0.3318 0 .

[0035] In some optional implementations, the second influence coefficient calculation model expression is:

[0036] flsip roll (i)=((((r5*coff(i)+r4)*coff(i)+r3)*coff(i)+r2)*coff(i)+r1)*coff(i)+r0;

[0037] Among them, i represents the rack number identification, flsip roll (i) represents the influence coefficient of the roller diameter corresponding to the i-th stand on the forward slip, r5, r4, r3, r2, r1 and r0 represent the roller diameter coefficients, coff(i) represents the intermediate calculation coefficient corresponding to the i-th stand, and the intermediate calculation coefficient coff(i) is expressed as:

[0038] coff(i)=sqrt(dia(i) / (2*then(i)));

[0039] Where i is the rack number, dia(i) is the roll diameter of the i-th rack, then(i) is the inlet thickness of the i-th rack, and sqrt is the square root calculation.

[0040] In some optional embodiments, the roller diameter coefficient is set to:

[0041] Coefficient name r5 r4 r3 r2 r1 r0 Coefficient value 0.00000471 -0.0002553 0.0053778 -0.05624 0.31057 0.21879 .

[0042] In some optional implementations, the forward slip coefficient calculation model expression is:

[0043] fslip(i)=1+0.92*flsip eps (i)*flsip roll (i);

[0044] Among them, i represents the rack number, fslip(i) represents the forward slip coefficient of the i-th rack, flsip eps (i) represents the influence coefficient of the pressure reduction rate corresponding to the i-th rack on the forward slip, flsip roll (i) represents the influence coefficient of the roll diameter corresponding to the i-th stand on the forward slip.

[0045] In some optional implementations, the relationship model expression between the forward slip coefficient and the backward slip coefficient is:

[0046] bslip(i)=then(i+1)*fslip(i) / then(i);

[0047] Where i represents the rack number, bslip(i) represents the backslip coefficient of the i-th rack, fslip(i) represents the forward slip coefficient of the i-th rack, then(i+1) represents the inlet thickness of the i+1-th rack, and then(i) represents the inlet thickness of the i-th rack.

[0048] In some optional implementations, the relationship model expression between the forward slip coefficient and the rack speed is:

[0049] v(i)=v ex (i) / fslip(i);

[0050] The relationship model expression between the backslip coefficient and the rack speed is:

[0051] v en (i) = v(i) * bslip(i);

[0052] The relationship model expression between the outlet velocity of the front rack and the inlet velocity of the rear rack is:

[0053] v ex (i) = v en (i+1);

[0054] Where i represents the stand number, v(i) represents the rolling speed of the i-th stand, and v ex (i) represents the exit speed of the i-th rack, fslip(i) represents the forward slip coefficient of the i-th rack, v en (i) represents the inlet velocity of the i-th rack, bslip(i) represents the backslip coefficient of the i-th rack, v en (i+1) represents the inlet velocity of the i+1th rack.

[0055] In some optional embodiments, the backslip correction coefficients for different steel grades are set as:

[0056]

[0057] When the backslip correction coefficient is a range value, the backslip correction coefficient includes the lower boundary value and excludes the upper boundary value;

[0058] The correction model expression of the back slip coefficient of the first stand of finishing rolling is:

[0059] bslip1(1)=bslip(1)*(1+corr);

[0060] Among them, bslip1(1) represents the backslip coefficient of the first stand of finishing rolling after correction, bslip(1) represents the backslip coefficient of the first stand of finishing rolling before correction, and corr represents the backslip correction coefficient.

[0061] In some optional embodiments, the relationship model expression between the roller speed before finishing and the entrance speed of the first finishing stand is:

[0062] v roll =v en (1);

[0063] Among them, v roll Indicates the roller speed before finishing rolling, v en (1) Indicates the inlet speed of the finishing mill head.

[0064] The main advantages of the technical solution of the present invention are as follows:

[0065] The front and rear slip control method of the finishing mill group of the present invention calculates the front slip coefficient and the rear slip coefficient of each stand according to the specific values ​​of the reduction rate, entrance thickness and roller diameter of each stand during finishing rolling, and calculates the speed of each stand according to the specific values ​​of the calculated front slip coefficient and rear slip coefficient of each stand, which can improve the calculation accuracy of the speed of each stand, ensure the consistency control of the second flow rate between stands, and thus improve the rolling stability between stands; in addition, the rear slip coefficient of the first finishing stand is corrected and adjusted according to the type of steel strip to be finish-rolled, and the entrance speed of the first finishing stand and the speed of the roller before finishing rolling are adjusted according to the corrected rear slip coefficient, which can avoid the waist collapse phenomenon of soft steel in front of the finishing mill and improve the surface quality of soft steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] The accompanying drawings described herein are used to provide a further understanding of the embodiments of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0067] In the picture:

[0068] Figure 1 This is a schematic diagram of the equipment layout of an existing 1549mm hot rolling production line;

[0069] Figure 2 The present invention provides a flowchart of a method for controlling forward and backward sliding of a finishing mill group. DETAILED DESCRIPTION

[0070] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0071] The technical solutions provided by the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0072] refer to Figure 2 The embodiment of the present invention provides a method for controlling the forward and backward sliding of a finishing mill, which is used in a 1549mm hot rolling production line and includes the following steps:

[0073] Step 1: Using a preset first influence coefficient calculation model, calculate the reduction ratio of each stand corresponding to the finished strip to obtain the influence coefficient of the reduction ratio on the forward slip;

[0074] Step 2: Using a preset second influence coefficient calculation model, calculate the inlet thickness and roll diameter of each stand corresponding to the finished strip to obtain the influence coefficient of the roll diameter on the forward slip;

[0075] Step 3: Using a preset forward slip coefficient calculation model, calculate the influence coefficient of the reduction rate on the forward slip and the influence coefficient of the roll diameter on the forward slip to obtain the forward slip coefficient of each stand;

[0076] Step 4: Calculate the forward slip coefficient of each rack using a preset relationship model between the forward slip coefficient and the backward slip coefficient to obtain the backward slip coefficient of each rack;

[0077] Step 5: Calculate the exit speed of the final finishing stand, the forward slip coefficient, and the backward slip coefficient of each stand using a preset relationship model between the forward slip coefficient and the stand speed, a relationship model between the backward slip coefficient and the stand speed, and a relationship model between the exit speed of the preceding stand and the entry speed of the following stand to obtain the entry speed, rolling speed, and exit speed of each stand.

[0078] Step 6, using the preset backslip correction coefficients of different steel grades and the preset backslip coefficient correction model of the finishing rolling first stand, the backslip coefficient of the finishing rolling first stand is calculated and processed to obtain a corrected backslip coefficient of the finishing rolling first stand;

[0079] Step 7, using a preset relationship model between the backslip coefficient and the stand speed, calculating and processing the corrected backslip coefficient of the first finishing stand to obtain the inlet speed of the first finishing stand;

[0080] Step 8: Calculate the inlet speed of the first finishing stand using the preset relationship model between the roller speed before finishing rolling and the inlet speed of the first finishing stand to obtain the roller speed before finishing rolling.

[0081] In the embodiment of the present invention, the reduction rate, inlet thickness and roll diameter of each stand, and the outlet speed of the final finishing stand are determined in advance based on parameter information of the strip to be finish-rolled and parameter information of the finishing mill group.

[0082] The forward and backward slip control method of the finishing mill provided by the embodiment of the present invention calculates the forward slip coefficient and backward slip coefficient of each frame according to the specific values ​​of the reduction rate, entrance thickness and roller diameter of each frame during finishing rolling, and calculates the speed of each frame according to the specific values ​​of the calculated forward slip coefficient and backward slip coefficient of each frame, which can improve the calculation accuracy of the speed of each frame, ensure the consistency control of the second flow rate between frames, and thus improve the rolling stability between frames; in addition, the backward slip coefficient of the first finishing rolling frame is corrected and adjusted according to the type of steel strip to be finish-rolled, and the entrance speed and the front roller speed of the first finishing rolling frame are adjusted according to the corrected backward slip coefficient, which can avoid the collapse of soft steel in front of the finishing mill and improve the surface quality of soft steel.

[0083] Furthermore, in the embodiment of the present invention, in step 1, the first influence coefficient calculation model expression is:

[0084] flsip eps (i)=((((e5*eps(i)+e4)*eps(i)+e3)*eps(i)+e2)*eps(i)+e1)*eps(i)+e0;

[0085] Among them, i represents the rack number identification, flsip eps (i) represents the influence coefficient of the reduction rate corresponding to the i-th rack on the forward slip, eps(i) represents the reduction rate of the i-th rack, and e5, e4, e3, e2, e1 and e0 represent the reduction rate coefficients.

[0086] In the embodiment of the present invention, the values ​​of the reduction coefficient are shown in the following table:

[0087] Table 1 Reduction coefficient

[0088] Coefficient name e5 e4 e3 e2 e1 e0 Coefficient value 7.42 -10.841 4.901 -0.8848 0.3318 0

[0089] Furthermore, in the embodiment of the present invention, in step 2, the second influence coefficient calculation model expression is:

[0090] flsip roll(i)=((((r5*coff(i)+r4)*coff(i)+r3)*coff(i)+r2)*coff(i)+r1)*coff(i)+r0;

[0091] Among them, i represents the rack number identification, flsip roll (i) represents the influence coefficient of the roller diameter corresponding to the i-th stand on the forward slip, r5, r4, r3, r2, r1 and r0 represent the roller diameter coefficients, coff(i) represents the intermediate calculation coefficient corresponding to the i-th stand, and the intermediate calculation coefficient coff(i) is expressed as:

[0092] coff(i)=sqrt(dia(i) / (2*then(i)));

[0093] Where i is the rack number, dia(i) is the roll diameter of the i-th rack, then(i) is the inlet thickness of the i-th rack, and sqrt is the square root calculation.

[0094] In the embodiment of the present invention, the values ​​of the roller diameter coefficient are shown in the following table:

[0095] Table 2 Roller diameter coefficient

[0096] Coefficient name r5 r4 r3 r2 r1 r0 Coefficient value 0.00000471 -0.0002553 0.0053778 -0.05624 0.31057 0.21879

[0097] Furthermore, in the embodiment of the present invention, in step 3, the forward slip coefficient calculation model expression is:

[0098] fslip(i)=1+0.92*flsip eps (i)*flsip roll (i);

[0099] Among them, i represents the rack number, fslip(i) represents the forward slip coefficient of the i-th rack, flsip eps (i) represents the influence coefficient of the pressure reduction rate corresponding to the i-th rack on the forward slip, flsip roll (i) represents the influence coefficient of the roll diameter corresponding to the i-th stand on the forward slip.

[0100] Furthermore, in the embodiment of the present invention, in step 4, the relationship model expression between the forward sliding coefficient and the backward sliding coefficient is:

[0101] bslip(i)=then(i+1)*fslip(i) / then(i);

[0102] Where i represents the rack number, bslip(i) represents the backslip coefficient of the i-th rack, fslip(i) represents the forward slip coefficient of the i-th rack, then(i+1) represents the inlet thickness of the i+1-th rack, and then(i) represents the inlet thickness of the i-th rack.

[0103] Furthermore, in the embodiment of the present invention, in step 5, the relationship model expression between the forward slip coefficient and the rack speed is:

[0104] v(i)=v ex (i) / fslip(i);

[0105] The relationship model expression between the backslip coefficient and the rack speed is:

[0106] v en (i) = v(i) * bslip(i);

[0107] The relationship model expression between the outlet velocity of the front rack and the inlet velocity of the rear rack is:

[0108] v ex (i) = v en (i+1);

[0109] Where i represents the stand number, v(i) represents the rolling speed of the i-th stand, and v ex (i) represents the exit speed of the i-th rack, fslip(i) represents the forward slip coefficient of the i-th rack, v en (i) represents the inlet velocity of the i-th rack, bslip(i) represents the backslip coefficient of the i-th rack, v en (i+1) represents the inlet velocity of the i+1th rack.

[0110] Furthermore, in the embodiment of the present invention, in step 6, the backslip correction coefficients for different steel grades are shown in the following table:

[0111] Table 3 Backslip correction coefficient

[0112]

[0113]

[0114] In Table 3, when the backslip correction coefficient is a range value, the value of the backslip correction coefficient includes the lower boundary value and excludes the upper boundary value, that is, "-0.15 to -0.11" means "-0.15 ≤ backslip correction coefficient < 0.11".

[0115] The correction model expression of the back slip coefficient of the first stand of finishing rolling is:

[0116] bslip1(1)=bslip(1)*(1+corr);

[0117] Wherein, bslip1(1) represents the backslip coefficient of the first finishing stand after correction, bslip(1) represents the backslip coefficient of the first finishing stand before correction, that is, the backslip coefficient of the first stand calculated in step 4 above, and corr represents the backslip correction coefficient.

[0118] Furthermore, in the embodiment of the present invention, the relationship model between the backslip coefficient and the rack speed in step 7 is the same as the relationship model between the backslip coefficient and the rack speed in step 5, and will not be described in detail here.

[0119] Furthermore, in the embodiment of the present invention, in step 8, the relationship model expression between the roller speed before finishing rolling and the entrance speed of the first finishing rolling stand is:

[0120] v roll =v en (1);

[0121] Among them, v roll Indicates the roller speed before finishing rolling, v en (1) represents the inlet speed of the first stand of the finishing mill, i.e. the inlet speed of the first stand.

[0122] In the embodiment of the present invention, by adjusting the roller speed before finishing rolling, the tension between the roller and the first stand of finishing rolling can be adjusted, thereby preventing the soft material strip from collapsing during finishing rolling and causing scratches on the lower surface.

[0123] To make the above technical solution of the present invention clearer, the technical solution of the present invention will be described clearly and completely in conjunction with specific embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0124] Example 1

[0125] This embodiment rolls ultrapure stainless steel, steel coil number: 946720301, steel grade: TTS443M; rough rolling outlet thickness is 34.434mm, rough rolling outlet width is 1173mm; finishing target thickness of strip steel is 3.265mm, finishing target width is 1145mm, and finishing target temperature is 900°C.

[0126] The relevant data of finishing rolling are as follows:

[0127] The exit speed of the finishing mill stand is 6.8m / s and the acceleration is 0.035m / s 2 ;

[0128]

[0129]

[0130] F0 to F6 represent the 1st to 7th racks.

[0131] Based on the above parameters, the forward and backward sliding control of the finishing mill is carried out through the following steps:

[0132] Step 1: Calculate the reduction ratio of each stand corresponding to the finished strip using the first influence coefficient calculation model specifically set above to obtain the influence coefficient of the reduction ratio on the forward slip;

[0133] The calculation process is as follows:

[0134] flsip eps (1)=((((e5*eps(1)+e4)*eps(1)+e3)*eps(1)+e2)*eps(1)+e1)*eps(1)+e0=((((7.42*37

[0135] .9%-10.841)*37.9%+4.901)*37.9%-0.8848)*37.9%+0.3318)*37.9%+0=0.099812;

[0136] flsip eps (2)=((((e5*eps(2)+e4)*eps(2)+e3)*eps(2)+e2)*eps(2)+e1)*eps(2)+e0=((((7.42*40

[0137] .2%-10.841)*40.2%+4.901)*40.2%-0.8848)*40.2%+0.3318)*40.2%+0=0.103566;

[0138] flsip eps (3)=((((e5*eps(3)+e4)*eps(3)+e3)*eps(3)+e2)*eps(3)+e1)*eps(3)+e0=((((7.42*31

[0139] 0.6%-10.841)*31.6%+4.901)*31.6%-0.8848)*31.6%+0.3318)*31.6%+0=0.086427;

[0140] flsip eps(4)=((((e5*eps(4)+e4)*eps(4)+e3)*eps(4)+e2)*eps(4)+e1)*eps(4)+e0=((((7.42*27

[0141] .4%-10.841)*27.4%+4.901)*27.4%-0.8848)*27.4%+0.3318)*27.4%+0=0.075659;

[0142] flsip eps (5)=((((e5*eps(5)+e4)*eps(5)+e3)*eps(5)+e2)*eps(5)+e1)*eps(5)+e0=((((7.42*22

[0143] .4%-10.841)*22.4%+4.901)*22.4%-0.8848)*22.4%+0.3318)*22.4%+0=0.061903;

[0144] flsip eps (6)=((((e5*eps(6)+e4)*eps(6)+e3)*eps(6)+e2)*eps(6)+e1)*eps(6)+e0=((((7.42*19

[0145] .7%-10.841)*19.7%+4.901)*19.7%-0.8848)*19.7%+0.3318)*19.7%+0=0.054370;

[0146] flsip eps (7)=((((e5*eps(7)+e4)*eps(7)+e3)*eps(7)+e2)*eps(7)+e1)*eps(7)+e0=((((7.42*16

[0147] .3%-10.841)*16.3%+4.901)*16.3%-0.8848)*16.3%+0.3318)*16.3%+0=0.045001.

[0148] Step 2: Using the second influence coefficient calculation model specifically set above, calculate the inlet thickness and roll diameter of each stand corresponding to the finished strip to obtain the influence coefficient of the roll diameter on the forward slip;

[0149] The calculation process is as follows:

[0150] memory(1)=sqrt(dia(1) / (2*then(1)))=sqrt(765.6 / (2*34.434))=3.334204;

[0151] memory(2)=sqrt(dia(2) / (2*then(2)))=sqrt(648.0 / (2*21.385))=3.892404;

[0152] memory(3)=sqrt(dia(3) / (2*then(3)))=sqrt(622.4 / (2*12.795))=4.931734;

[0153] memory(4)=sqrt(dia(4) / (2*then(4)))=sqrt(635.6 / (2*8.754))=6.025231;

[0154] memory(5)=sqrt(dia(5) / (2*then(5)))=sqrt(642.5 / (2*6.358))=7.108227;

[0155] memory(6)=sqrt(dia(6) / (2*then(6)))=sqrt(625.3 / (2*4.934))=7.960304;

[0156] memory(7)=sqrt(dia(7) / (2*then(7)))=sqrt(676.5 / (2*3.962))=9.239781;

[0157] zip roll (1)=(((((r5*memory(1)+r4)*memory(1)+r3)*memory(1)+r2)*memory(1)+r1)*memory(1)+r0=((((0.000

[0158] 00471*3.334204-0.0002553)*3.334204+0.0053778)*3.334204-0.05624)*3.334204+0.31057)*3.334204+0.21879=0.798802;

[0159] zip roll (2)=((((r5*memory(2)+r4)*memory(2)+r3)*memory(2)+r2)*memory(2)+r1)*memory(2)+r0=((((0.000

[0160] 00471*3.892404-0.0002553)*3.892404+0.0053778)*3.892404-0.05624)*3.892404+0.31057)*3.892404+0.21879=0.838323;

[0161] zip roll (3)=((((r5*memory(3)+r4)*memory(3)+r3)*memory(3)+r2)*memory(3)+r1)*memory(3)+r0=((((0.000

[0162] 00471*4.931734-0.0002553)*4.931734+0.0053778)*4.931734-0.05624)*4.931734+0.31057)*4.931734+0.21879=0.890350;

[0163] zip roll (4)=(((((r5*memory(4)+r4)*memory(4)+r3)*memory(4)+r2)*memory(4)+r1)*memory(4)+r0=((((0.000

[0164] 00471*6.025231-0.0002553)*6.025231+0.0053778)*6.025231-0.05624)*6.025231+0.31057)*6.025231+0.21879=0.925595;

[0165] zip roll (5)=(((((r5*memory(5)+r4)*memory(5)+r3)*memory(5)+r2)*memory(5)+r1)*memory(5)+r0=((((0.000

[0166] 00471*7.108227-0.0002553)*7.108227+0.0053778)*7.108227-0.05624)*7.108227+0.31057)*7.108227+0.21879=0.949932;

[0167] zip roll(6)=((((r5*coff(6)+r4)*coff(6)+r3)*coff(6)+r2)*coff(6)+r1)*coff(6)+r0=((((0.000

[0168] 00471*7.960304-0.0002553)*7.960304+0.0053778)*7.960304-0.05624)*7.960304+0.31057)*7.960304+0.21879=0.965381;

[0169] flsip roll (7)=((((r5*coff(7)+r4)*coff(7)+r3)*coff(7)+r2)*coff(7)+r1)*coff(7)+r0=((((0.000

[0170] 00471*9.239781-0.0002553)*9.239781+0.0053778)*9.239781-0.05624)*9.239781+0.31057)*9.239781+0.21879=0.985572.

[0171] Step 3: Using the above-specified forward slip coefficient calculation model, calculate the influence coefficient of the reduction rate on the forward slip and the influence coefficient of the roll diameter on the forward slip to obtain the forward slip coefficient of each stand;

[0172] The calculation process is as follows:

[0173] fslip(1)=1+0.92*flsip eps (1)*flsip roll (1) = 1 + 0.92 * 0.099812 * 0.798802 = 1.073352;

[0174] fslip(2)=1+0.92*flsip eps (2)*flsip roll (2) = 1 + 0.92 * 0.103566 * 0.838323 = 1.079876;

[0175] fslip(3)=1+0.92*flsip eps (3)*flsip roll (3) = 1 + 0.92 * 0.086427 * 0.890350 = 1.070794;

[0176] fslip(4)=1+0.92*flsip eps (4)*flsip roll (4) = 1 + 0.92 * 0.075659 * 0.925595 = 1.064427;

[0177] fslip(5)=1+0.92*flsip eps (5)*flsip roll (5) = 1 + 0.92 * 0.061903 * 0.949932 = 1.054099;

[0178] fslip(6)=1+0.92*flsip eps (6)*flsip roll (6) = 1 + 0.92 * 0.054370 * 0.965381 = 1.048289;

[0179] fslip(7)=1+0.92*flsip eps (7)*flsip roll (7) = 1 + 0.92 * 0.045001 * 0.985572 = 1.040804.

[0180] Step 4: Calculate the forward slip coefficient of each rack using the relationship model between the forward slip coefficient and the backward slip coefficient specifically defined above to obtain the backward slip coefficient of each rack;

[0181] The calculation process is as follows:

[0182] bslip(1)=then(2)*fslip(1) / then(1)=21.385*1.073352 / 34.434=0.666598;

[0183] bslip(2)=then(3)*fslip(2) / then(2)=12.795*1.079876 / 21.385=0.646108;

[0184] bslip(3)=then(4)*fslip(3) / then(3)=8.754*1.070794 / 12.795=0.732609;

[0185] bslip(4)=then(5)*fslip(4) / then(4)=6.358*1.064427 / 8.754=0.773090;

[0186] bslip(5)=then(6)*fslip(5) / then(5)=4.934*1.054099 / 6.358=0.818013;

[0187] bslip(6)=then(7)*fslip(6) / then(6)=3.962*1.048289 / 4.934=0.841775;

[0188] bslip(7)=then(8)*fslip(7) / then(7)=3.315*1.040804 / 3.962=0.870839;

[0189] Among them, then(8) represents the outlet thickness of the 7th rack.

[0190] Step 5: Using the above-defined relationship models between the forward slip coefficient and the stand speed, the relationship model between the backward slip coefficient and the stand speed, and the relationship model between the exit speed of the leading stand and the entry speed of the trailing stand, the exit speed of the final finishing stand, the forward slip coefficient, and the backward slip coefficient of each stand are calculated to obtain the entry speed, rolling speed, and exit speed of each stand.

[0191] The calculation process is as follows:

[0192] v(7)=v ex (7) / fslip(7)=6.8 / 1.040804=6.53(m / s);

[0193] v ex (6) = v en (7)=v(7)*bslip(7)=6.53*0.870839=5.69(m / s);

[0194] v(6)=v ex (6) / fslip(6)=5.69 / 1.048289=5.43(m / s);

[0195] v ex (5) = v en (6)=v(6)*bslip(6)=5.43*0.841775=4.57(m / s);

[0196] v(5)=v ex (5) / fslip(5)=4.57 / 1.054099=4.33(m / s);

[0197] v ex (4) = v en(5) = v(5) * bslip(5) = 4.33 * 0.818013 = 3.55 (m / s) ;

[0198] v(4) = v ex (4) / fslip(4) = 3.55 / 1.064427 = 3.33 (m / s) ;

[0199] v ex (3) = v en (4) = v(4) * bslip(4) = 3.33 * 0.773090 = 2.58 (m / s) ;

[0200] v(3) = v ex (3) / fslip(3) = 2.58 / 1.070794 = 2.40 (m / s) ;

[0201] v ex (2) = v en (3) = v(3) * bslip(3) = 2.40 * 0.732609 = 1.76 (m / s) ;

[0202] v(2) = v ex (2) / fslip(2) = 1.76 / 1.079876 = 1.63 (m / s) ;

[0203] v ex (1) = v en (2) = v(2) * bslip(2) = 1.63 * 0.646108 = 1.05 (m / s) ;

[0204] v(1) = v ex (1) / fslip(1) = 1.05 / 1.073352 = 0.98 (m / s) ;

[0205] v en (1) = v(1) * bslip(1) = 0.98 * 0.666598 = 0.65 (m / s).

[0206] Step 6, using the above specific defined different steel grade post slip correction factor and finishing mill first stand post slip correction model, the post slip correction factor of the finishing mill first stand is calculated and processed, and the corrected post slip correction factor of the finishing mill first stand is obtained;

[0207] The calculation and processing process is as follows:

[0208] Since the example is rolling ultra-pure stainless steel, the rough rolling exit thickness is 34.434 mm, and the finishing target width is 1145 mm, so the post slip correction factor corr is -0.1;

[0209] The corrected backslip coefficient of the finishing first stand is:

[0210] bslip1(1)=bslip(1)*(1+corr)=0.666598*(1-0.1)=0.599938.

[0211] Step 7, using the relationship model between the backslip coefficient and the stand speed specifically set above, the corrected backslip coefficient of the first finishing stand is calculated to obtain the inlet speed of the first finishing stand;

[0212] The calculation process is as follows:

[0213] v en (1)=v(1)*bslip1(1)=0.98*0.599938=0.59(m / s).

[0214] Step 8: using the relationship model between the roller speed before finishing rolling and the inlet speed of the first finishing stand specifically set above, the inlet speed of the first finishing stand is calculated to obtain the roller speed before finishing rolling;

[0215] The calculation process is as follows:

[0216] v roll =v en (1) = 0.59 (m / s).

[0217] According to the above steps, the final roller speed, forward slip coefficient, backward slip coefficient and speed of each frame are as follows:

[0218] frame roll F0 F1 F2 F3 F4 F5 F6 fslip 1.073352 1.079876 1.070794 1.064427 1.054099 1.048289 1.040804 bslip 0.599938 0.646108 0.732609 0.773090 0.818013 0.841775 0.870839 <![CDATA[v en ]]> 0.59 1.05 1.76 2.58 3.55 4.57 5.69 v 0.98 1.63 2.40 3.33 4.33 5.43 6.53 <![CDATA[v ex ]]> 1.05 1.76 2.58 3.55 4.57 5.69 6.80 v roll ]]> 0.59

[0219] Finish rolling is carried out based on the various parameters determined above. During the rolling process, the control between stands is stable and there is no waist collapse phenomenon before finish rolling.

[0220] Example 2

[0221] This embodiment rolls 430 stainless steel, steel coil number: 944932701, steel grade: SUS430FD; the rough rolling outlet thickness is 34.03mm, the rough rolling outlet width is 1064.5mm; the finishing target thickness of the strip is 2.85mm, the finishing target width is 1040mm, and the finishing target temperature is 940°C.

[0222] The relevant data of finishing rolling are as follows:

[0223] The exit speed of the finishing mill stand is 7.8m / s and the acceleration is 0.045m / s 2 ;

[0224] frame F0 F1 F2 F3 F4 F5 F6 Inlet thickness (mm) 34.03 20.53 12.25 8.05 5.56 4.11 3.31 Export thickness (mm) 20.53 12.25 8.05 5.56 4.11 3.31 2.86 Inlet temperature (℃) 977.2 968.82 961.22 953.25 945.9 938.47 929.88 Outlet temperature (℃) 968.82 961.22 953.25 945.9 938.47 929.88 918.71 Reduction rate (%) 39.7 40.3 34.3 30.9 26.2 19.5 13.4 Roller diameter (mm) 777.77 659.23 639.97 604.65 633.09 608.1 659.81

[0225] F0~F6 represent the first rack to the seventh rack.

[0226] Based on the above parameters, the front and rear slip control of the finishing mill train is carried out by the following steps:

[0227] Step 1, using the first influence coefficient calculation model set above, the reduction rate of each rack corresponding to the strip to be finished is calculated and processed, and the influence coefficient of the reduction rate on the front slip is obtained;

[0228] The calculation and processing process is as follows:

[0229] flsip eps (1) = (((((e5*eps(1) + e4) *eps(1) + e3) *eps(1) + e2) *eps(1) + e1) *eps(1) + e0) = 0.102809;

[0230] flsip eps (2) = (((((e5*eps(2) + e4) *eps(2) + e3) *eps(2) + e2) *eps(2) + e1) *eps(2) + e0) = 0.103714;

[0231] flsip eps (3) = (((((e5*eps(3) + e4) *eps(3) + e3) *eps(3) + e2) *eps(3) + e1) *eps(3) + e0) = 0.092658;

[0232] flsip eps (4) = (((((e5*eps(4) + e4) *eps(4) + e3) *eps(4) + e2) *eps(4) + e1) *eps(4) + e0) = 0.084711;

[0233] flsip eps (5) = (((((e5*eps(5) + e4) *eps(5) + e3) *eps(5) + e2) *eps(5) + e1) *eps(5) + e0) = 0.072416;

[0234] flsip eps (6) = (((((e5*eps(6) + e4) *eps(6) + e3) *eps(6) + e2) *eps(6) + e1) *eps(6) + e0) = 0.053814;

[0235] flsip eps(7)=((((e5*eps(7)+e4)*eps(7)+e3)*eps(7)+e2)*eps(7)+e1)*eps(7)+e0=0.037191.

[0236] Step 2: Using the second influence coefficient calculation model specifically set above, calculate the inlet thickness and roll diameter of each stand corresponding to the finished strip to obtain the influence coefficient of the roll diameter on the forward slip;

[0237] The calculation process is as follows:

[0238] coff(1)=sqrt(dia(1) / (2*then(1)))=sqrt(777.77 / 2 / 34.03))=3.380490;

[0239] coff(2)=sqrt(dia(2) / (2*then(2)))=sqrt(659.23 / 2 / 20.53))=4.006905;

[0240] coff(3)=sqrt(dia(3) / (2*then(3)))=sqrt(639.97 / 2 / 12.25))=5.110893;

[0241] coff(4)=sqrt(dia(4) / (2*then(4)))=sqrt(604.65 / 2 / 8.05))=6.128287;

[0242] coff(5)=sqrt(dia(5) / (2*then(5)))=sqrt(633.09 / 2 / 5.56))=7.545366;

[0243] coff(6)=sqrt(dia(6) / (2*then(6)))=sqrt(608.1 / 2 / 4.11))=8.601052;

[0244] coff(7)=sqrt(dia(7) / (2*then(7)))=sqrt(659.81 / 2 / 3.31))=9.983446;

[0245] flsip roll (1)=((((r5*coff(1)+r4)*coff(1)+r3)*coff(1)+r2)*coff(1)+r1)*coff(1)+r0=0.802464;

[0246] flsip roll(2)=((((r5*coff(2)+r4)*coff(2)+r3)*coff(2)+r2)*coff(2)+r1)*coff(2)+r0=0.845285;

[0247] flsip roll (3)=((((r5*coff(3)+r4)*coff(3)+r3)*coff(3)+r2)*coff(3)+r1)*coff(3)+r0=0.897203;

[0248] flsip roll (4)=((((r5*coff(4)+r4)*coff(4)+r3)*coff(4)+r2)*coff(4)+r1)*coff(4)+r0=0.928251;

[0249] flsip roll (5)=((((r5*coff(5)+r4)*coff(5)+r3)*coff(5)+r2)*coff(5)+r1)*coff(5)+r0=0.958131;

[0250] flsip roll (6)=((((r5*coff(6)+r4)*coff(6)+r3)*coff(6)+r2)*coff(6)+r1)*coff(6)+r0=0.975839;

[0251] flsip roll (7)=((((r5*coff(7)+r4)*coff(7)+r3)*coff(7)+r2)*coff(7)+r1)*coff(7)+r0=0.996068.

[0252] Step 3: Using the above-specified forward slip coefficient calculation model, calculate the influence coefficient of the reduction rate on the forward slip and the influence coefficient of the roll diameter on the forward slip to obtain the forward slip coefficient of each stand;

[0253] The calculation process is as follows:

[0254] fslip(1)=1+0.92*flsip eps (1)*flsip roll (1) = 1 + 0.92 * 0.102809 * 0.802464 = 1.075900;

[0255] fslip(2)=1+0.92*flsip eps(2)*flsip roll (2) = 1 + 0.92 * 0.103714 * 0.845285 = 1.080654;

[0256] fslip(3)=1+0.92*flsip eps (3)*flsip roll (3) = 1 + 0.92 * 0.092658 * 0.897203 = 1.076482;

[0257] fslip(4)=1+0.92*flsip eps (4)*flsip roll (4) = 1 + 0.92 * 0.084711 * 0.928251 = 1.072342;

[0258] fslip(5)=1+0.92*flsip eps (5)*flsip roll (5) = 1 + 0.92 * 0.072416 * 0.958131 = 1.063833;

[0259] fslip(6)=1+0.92*flsip eps (6)*flsip roll (6) = 1 + 0.92 * 0.053814 * 0.975839 = 1.048313;

[0260] fslip(7)=1+0.92*flsip eps (7)*flsip roll (7) = 1 + 0.92 * 0.037191 * 0.996068 = 1.034081.

[0261] Step 4: Calculate the forward slip coefficient of each rack using the relationship model between the forward slip coefficient and the backward slip coefficient specifically defined above to obtain the backward slip coefficient of each rack;

[0262] The calculation process is as follows:

[0263] bslip(1)=then(2)*fslip(1) / then(1)=20.53*1.075900 / 34.03=0.649081;

[0264] bslip(2)=then(3)*fslip(2) / then(2)=12.25*1.080654 / 20.53=0.644813;

[0265] bslip(3)=then(4)*fslip(3) / then(3)=8.05*1.076482 / 12.25=0.707403;

[0266] bslip(4)=then(5)*fslip(4) / then(4)=5.56*1.072342 / 8.05=0.740649;

[0267] bslip(5)=then(6)*fslip(5) / then(5)=4.11*1.063833 / 5.56=0.786395;

[0268] bslip(6)=then(7)*fslip(6) / then(6)=3.31*1.048313 / 4.11=0.844261;

[0269] bslip(7)=then(8)*fslip(7) / then(7)=2.86*1.034081 / 3.31=0.893496;

[0270] Among them, then(8) represents the outlet thickness of the 7th rack.

[0271] Step 5: Using the above-defined relationship models between the forward slip coefficient and the stand speed, the relationship model between the backward slip coefficient and the stand speed, and the relationship model between the exit speed of the leading stand and the entry speed of the trailing stand, the exit speed of the final finishing stand, the forward slip coefficient, and the backward slip coefficient of each stand are calculated to obtain the entry speed, rolling speed, and exit speed of each stand.

[0272] The calculation process is as follows:

[0273] v(7)=v ex (7) / fslip(7)=7.8 / 1.034081=7.54(m / s);

[0274] v ex (6) = v en (7)=v(7)*bslip(7)=7.54*0.893496=6.74(m / s);

[0275] v(6)=v ex (6) / fslip(6)=6.74 / 1.048313=6.43(m / s);

[0276] v ex (5) = v en(6)=v(6)*bslip(6)=6.43*0.844261=5.43(m / s);

[0277] v(5)=v ex (5) / fslip(5)=5.43 / 1.063833=5.10(m / s);

[0278] v ex (4)=v en (5)=v(5)*bslip(5)=5.10*0.786395=4.01(m / s);

[0279] v(4)=v ex (4) / fslip(4)=4.01 / 1.072342=3.74(m / s);

[0280] v ex (3)=v en (4)=v(4)*bslip(4)=3.74*0.740649=2.77(m / s);

[0281] v(3)=v ex (3) / fslip(3)=2.77 / 1.076482=2.57(m / s);

[0282] v ex (2)=v en (3)=v(3)*bslip(3)=2.57*0.707403=1.82(m / s);

[0283] v(2)=v ex (2) / fslip(2)=1.82 / 1.080654=1.69(m / s);

[0284] v ex (1)=v en (2)=v(2)*bslip(2)=1.69*0.644813=1.09(m / s);

[0285] v(1)=v ex (1) / fslip(1)=1.09 / 1.075900=1.01(m / s);

[0286] v en (1)=v(1)*bslip(1)=1.01*0.649081=0.66(m / s)。

[0287] Step 6: Calculate the backslip coefficient of the first finishing stand using the backslip correction coefficients of the different steel grades and the backslip coefficient correction model of the first finishing stand, to obtain a corrected backslip coefficient of the first finishing stand;

[0288] The calculation process is as follows:

[0289] Since this embodiment rolls 430 stainless steel, the strip thickness at the rough rolling exit is 34.03 mm, and the target width of the finishing rolling is 1040 mm, the backslip correction coefficient corr is -0.08;

[0290] The corrected backslip coefficient of the finishing first stand is:

[0291] bslip1(1)=bslip(1)*(1+corr)=0.649081*(1-0.08)=0.597155.

[0292] Step 7, using the relationship model between the backslip coefficient and the stand speed specifically set above, the corrected backslip coefficient of the first finishing stand is calculated to obtain the inlet speed of the first finishing stand;

[0293] The calculation process is as follows:

[0294] v en (1)=v(1)*bslip1(1)=1.01*0.597155=0.60(m / s).

[0295] Step 8: using the relationship model between the roller speed before finishing rolling and the inlet speed of the first finishing stand specifically set above, the inlet speed of the first finishing stand is calculated to obtain the roller speed before finishing rolling;

[0296] The calculation process is as follows:

[0297] v roll =v en (1) = 0.60 (m / s).

[0298] According to the above steps, the final roller speed, forward slip coefficient, backward slip coefficient and speed of each frame are as follows:

[0299] frame roll F0 F1 F2 F3 F4 F5 F6 fslip 1.075900 1.080654 1.076482 1.072342 1.063833 1.048313 1.034081 bslip 0.597155 0.644813 0.707403 0.740649 0.786395 0.844261 0.893496 <![CDATA[v en ]]> 0.60 1.09 1.82 2.77 4.01 5.43 6.74 v 1.01 1.69 2.57 3.74 5.10 6.43 7.54 <![CDATA[v ex ]]> 1.09 1.82 2.77 4.01 5.43 6.74 7.80 <![CDATA[v roll ]]> 0.60

[0300] Finish rolling is carried out based on the various parameters determined above. During the rolling process, the control between stands is stable and there is no waist collapse phenomenon before finish rolling.

[0301] Example 3

[0302] This embodiment rolls 400 series stainless steel, steel coil number: 945835201, steel grade: 0CR13R; the rough rolling outlet thickness is 35.6mm, the rough rolling outlet width is 1282.1mm; the finishing target thickness of the strip is 4.0mm, the finishing target width is 1255mm, and the finishing target temperature is 920°C.

[0303] The relevant data of finishing rolling are as follows:

[0304] The exit speed of the finishing mill stand is 6.8m / s and the acceleration is 0.042m / s 2 ;

[0305]

[0306]

[0307] F0 to F6 represent the 1st to 7th racks.

[0308] Based on the above parameters, the forward and backward sliding control of the finishing mill is carried out through the following steps:

[0309] Step 1: Calculate the reduction ratio of each stand corresponding to the finished strip using the first influence coefficient calculation model specifically set above to obtain the influence coefficient of the reduction ratio on the forward slip;

[0310] The calculation process is as follows:

[0311] flsip eps (1)=((((e5*eps(1)+e4)*eps(1)+e3)*eps(1)+e2)*eps(1)+e1)*eps(1)+e0=0.094371;

[0312] flsip eps (2)=((((e5*eps(2)+e4)*eps(2)+e3)*eps(2)+e2)*eps(2)+e1)*eps(2)+e0=0.092876;

[0313] flsip eps (3)=((((e5*eps(3)+e4)*eps(3)+e3)*eps(3)+e2)*eps(3)+e1)*eps(3)+e0=0.084214;

[0314] flsip eps (4)=((((e5*eps(4)+e4)*eps(4)+e3)*eps(4)+e2)*eps(4)+e1)*eps(4)+e0=0.072688;

[0315] flsip eps (5)=((((e5*eps(5)+e4)*eps(5)+e3)*eps(5)+e2)*eps(5)+e1)*eps(5)+e0=0.061344;

[0316] flsip eps (6)=((((e5*eps(6)+e4)*eps(6)+e3)*eps(6)+e2)*eps(6)+e1)*eps(6)+e0=0.054370;

[0317] flsip eps (7)=((((e5*eps(7)+e4)*eps(7)+e3)*eps(7)+e2)*eps(7)+e1)*eps(7)+e0=0.044457.

[0318] Step 2: Using the second influence coefficient calculation model specifically set above, calculate the inlet thickness and roll diameter of each stand corresponding to the finished strip to obtain the influence coefficient of the roll diameter on the forward slip;

[0319] The calculation process is as follows:

[0320] coff(1)=sqrt(dia(1) / (2*then(1)))=sqrt(772.85 / 2 / 35.6))=3.294637;

[0321] coff(2)=sqrt(dia(2) / (2*then(2)))=sqrt(677.4 / 2 / 23.11))=3.828315;

[0322] coff(3)=sqrt(dia(3) / (2*then(3)))=sqrt(623.98 / 2 / 15.16))=4.536498;

[0323] coff(4)=sqrt(dia(4) / (2*then(4)))=sqrt(652.31 / 2 / 10.5))=5.573364;

[0324] coff(5)=sqrt(dia(5) / (2*then(5)))=sqrt(635.2 / 2 / 7.73))=6.409889;

[0325] coff(6)=sqrt(dia(6) / (2*then(6)))=sqrt(606 / 2 / 6.02))=7.094521;

[0326] memory(7)=sqrt(dia(7) / (2*then(7)))=sqrt(663.3 / 2 / 4.83))=8.286410;

[0327] zip roll (1)=(((((r5*memory(1)+r4)*memory(1)+r3)*memory(1)+r2)*memory(1)+r1)*memory(1)+r0=0.795610;

[0328] zip roll (2)=((((r5*memory(2)+r4)*memory(2)+r3)*memory(2)+r2)*memory(2)+r1)*memory(2)+r0=0.834268;

[0329] zip roll (3)=((((r5*memory(3)+r4)*memory(3)+r3)*memory(3)+r2)*memory(3)+r1)*memory(3)+r0=0.873277;

[0330] zip roll (4)=(((((r5*memory(4)+r4)*memory(4)+r3)*memory(4)+r2)*memory(4)+r1)*memory(4)+r0=0.912773;

[0331] zip roll (5)=(((((r5*coff(5)+r4)*coff(5)+r3)*coff(5)+r2)*coff(5)+r1)*coff(5)+r0=0.935087;

[0332] zip roll (6)=(((((r5*memory(6)+r4)*memory(6)+r3)*memory(6)+r2)*memory(6)+r1)*memory(6)+r0=0.949664;

[0333] zip roll (7)=((((r5*memory(7)+r4)*memory(7)+r3)*memory(7)+r2)*memory(7)+r1)*memory(7)+r0=0.970800。

[0334] Step 3: Using the above-specified forward slip coefficient calculation model, calculate the influence coefficient of the reduction rate on the forward slip and the influence coefficient of the roll diameter on the forward slip to obtain the forward slip coefficient of each stand;

[0335] The calculation process is as follows:

[0336] fslip(1)=1+0.92*flsip eps (1)*flsip roll (1) = 1 + 0.92 * 0.094371 * 0.795610 = 1.069076;

[0337] fslip(2)=1+0.92*flsip eps (2)*flsip roll (2) = 1 + 0.92 * 0.092876 * 0.834268 = 1.071285;

[0338] fslip(3)=1+0.92*flsip eps (3)*flsip roll (3) = 1 + 0.92 * 0.084214 * 0.873277 = 1.067659;

[0339] fslip(4)=1+0.92*flsip eps (4)*flsip roll (4) = 1 + 0.92 * 0.072688 * 0.912773 = 1.061040;

[0340] fslip(5)=1+0.92*flsip eps (5)*flsip roll (5) = 1 + 0.92 * 0.061344 * 0.935087 = 1.052773;

[0341] fslip(6)=1+0.92*flsip eps (6)*flsip roll (6) = 1 + 0.92 * 0.054370 * 0.949664 = 1.047502;

[0342] fslip(7)=1+0.92*flsip eps (7)*flsip roll (7) = 1 + 0.92 * 0.044457 * 0.970800 = 1.039706.

[0343] Step 4: Calculate the forward slip coefficient of each rack using the relationship model between the forward slip coefficient and the backward slip coefficient specifically defined above to obtain the backward slip coefficient of each rack;

[0344] The calculation process is as follows:

[0345] bslip(1)=then(2)*fslip(1) / then(1)=23.11*1.069076 / 35.6=0.693999;

[0346] bslip(2)=then(3)*fslip(2) / then(2)=15.16*1.071285 / 23.11=0.702755;

[0347] bslip(3)=then(4)*fslip(3) / then(3)=10.5*1.067659 / 15.16=0.739474;

[0348] bslip(4)=then(5)*fslip(4) / then(4)=7.73*1.061040 / 10.5=0.781128;

[0349] bslip(5)=then(6)*fslip(5) / then(5)=6.02*1.052773 / 7.73=0.819883;

[0350] bslip(6)=then(7)*fslip(6) / then(6)=4.83*1.047502 / 6.02=0.840438;

[0351] bslip(7)=then(8)*fslip(7) / then(7)=4.05*1.039706 / 4.83=0.871803;

[0352] Among them, then(8) represents the outlet thickness of the 7th rack.

[0353] Step 5: Using the above-defined relationship models between the forward slip coefficient and the stand speed, the relationship model between the backward slip coefficient and the stand speed, and the relationship model between the exit speed of the leading stand and the entry speed of the trailing stand, the exit speed of the final finishing stand, the forward slip coefficient, and the backward slip coefficient of each stand are calculated to obtain the entry speed, rolling speed, and exit speed of each stand.

[0354] The calculation process is as follows:

[0355] v(7)=v ex(7) / fslip(7)=6.80 / 1.039706=6.54(m / s);

[0356] v ex (6)=v en (7)=v(7)*bslip(7)=6.54*0.871803=5.70(m / s);

[0357] v(6)=v ex (6) / fslip(6)=5.70 / 1.047502=5.44(m / s);

[0358] v ex (5)=v en (6)=v(6)*bslip(6)=5.44*0.840438=4.57(m / s);

[0359] v(5)=v ex (5) / fslip(5)=4.57 / 1.052773=4.35(m / s);

[0360] v ex (4)=v en (5)=v(5)*bslip(5)=4.35*0.819883=3.56(m / s);

[0361] v(4)=v ex (4) / fslip(4)=3.56 / 1.061040=3.36(m / s);

[0362] v ex (3)=v en (4)=v(4)*bslip(4)=3.36*0.781128=2.62(m / s);

[0363] v(3)=v ex (3) / fslip(3)=2.62 / 1.067659=2.46(m / s);

[0364] v ex (2)=v en (3)=v(3)*bslip(3)=2.46*0.739474=1.82(m / s);

[0365] v(2)=v ex (2) / fslip(2)=1.82 / 1.071285=1.70(m / s);

[0366] v ex (1)=ven (2)=v(2)*bslip(2)=1.70*0.702755=1.19(m / s);

[0367] v(1)=v ex (1) / fslip(1)=1.19 / 1.069076=1.11(m / s);

[0368] v en (1)=v(1)*bslip(1)=1.11*0.693999=0.77(m / s).

[0369] Step 6: Calculate the backslip coefficient of the first finishing stand using the backslip correction coefficients of the different steel grades and the backslip coefficient correction model of the first finishing stand, to obtain a corrected backslip coefficient of the first finishing stand;

[0370] The calculation process is as follows:

[0371] Since this embodiment rolls 0CR13 stainless steel, the strip thickness at the rough rolling exit is 35.6 mm, and the target width of the finishing rolling is 1255 mm, the backslip correction coefficient corr is -0.06;

[0372] The corrected backslip coefficient of the finishing first stand is:

[0373] bslip1(1)=bslip(1)*(1+corr)=0.693999*(1-0.06)=0.652359.

[0374] Step 7, using the relationship model between the backslip coefficient and the stand speed specifically set above, the corrected backslip coefficient of the first finishing stand is calculated to obtain the inlet speed of the first finishing stand;

[0375] The calculation process is as follows:

[0376] v en (1)=v(1)*bslip1(1)=1.11*0.652359=0.73(m / s).

[0377] Step 8: using the relationship model between the roller speed before finishing rolling and the inlet speed of the first finishing stand specifically set above, the inlet speed of the first finishing stand is calculated to obtain the roller speed before finishing rolling;

[0378] The calculation process is as follows:

[0379] v roll =v en (1) = 0.73 (m / s).

[0380] According to the above steps, the final roller speed, forward slip coefficient, backward slip coefficient and speed of each frame are as follows:

[0381] frame roll F0 F1 F2 F3 F4 F5 F6 fslip 1.069076 1.071285 1.067659 1.061040 1.052773 1.047502 1.039706 bslip 0.652359 0.702755 0.739474 0.781128 0.819883 0.840438 0.871803 <![CDATA[v en ]]> 0.73 1.19 1.82 2.62 3.56 4.57 5.70 v 1.11 1.70 2.46 3.36 4.35 5.44 6.54 <![CDATA[v ex ]]> 1.19 1.82 2.62 3.56 4.57 5.70 6.80 <![CDATA[v roll ]]> 0.73

[0382] Finish rolling is carried out based on the various parameters determined above. During the rolling process, the control between stands is stable and there is no waist collapse phenomenon before finish rolling.

[0383] Example 4

[0384] In this embodiment, cold rolled material is rolled, steel coil number: 945216901, steel grade: Q195L; the rough rolling outlet thickness is 40.79 mm, the rough rolling outlet width is 1306.4 mm; the strip finishing target thickness is 2.96 mm, the finishing target width is 1265 mm, and the finishing target temperature is 900°C.

[0385] The relevant data of finishing rolling are as follows:

[0386] The exit speed of the finishing mill stand is 8.0m / s and the acceleration is 0.04m / s 2 ;

[0387] frame F0 F1 F2 F3 F4 F5 F6 Inlet thickness (mm) 40.79 22.77 13.46 8.75 6.31 4.64 3.6 Export thickness (mm) 22.77 13.46 8.75 6.31 4.64 3.6 3.02 Inlet temperature (℃) 1036.55 1021.23 968.89 955.28 940.96 926.48 912.13 Outlet temperature (℃) 1021.23 968.89 955.28 940.96 926.48 912.13 896.17 Reduction rate (%) 44.2 40.9 35 27.9 26.4 22.5 16.1 Roller diameter (mm) 773.21 660 628.24 649.56 634.9 627.51 655.25

[0388] F0 to F6 represent the 1st to 7th racks.

[0389] Based on the above parameters, the forward and backward sliding control of the finishing mill is carried out through the following steps:

[0390] Step 1: Calculate the reduction ratio of each stand corresponding to the finished strip using the first influence coefficient calculation model specifically set above to obtain the influence coefficient of the reduction ratio on the forward slip;

[0391] The calculation process is as follows:

[0392] flsip eps (1)=((((e5*eps(1)+e4)*eps(1)+e3)*eps(1)+e2)*eps(1)+e1)*eps(1)+e0=0.108408;

[0393] flsip eps (2)=((((e5*eps(2)+e4)*eps(2)+e3)*eps(2)+e2)*eps(2)+e1)*eps(2)+e0=0.104571;

[0394] flsip eps(3)=((((e5*eps(3)+e4)*eps(3)+e3)*eps(3)+e2)*eps(3)+e1)*eps(3)+e0=0.094161;

[0395] flsip eps (4)=((((e5*eps(4)+e4)*eps(4)+e3)*eps(4)+e2)*eps(4)+e1)*eps(4)+e0=0.076992;

[0396] flsip eps (5)=((((e5*eps(5)+e4)*eps(5)+e3)*eps(5)+e2)*eps(5)+e1)*eps(5)+e0=0.072960;

[0397] flsip eps (6)=((((e5*eps(6)+e4)*eps(6)+e3)*eps(6)+e2)*eps(6)+e1)*eps(6)+e0=0.062182;

[0398] flsip eps (7)=((((e5*eps(7)+e4)*eps(7)+e3)*eps(7)+e2)*eps(7)+e1)*eps(7)+e0=0.044457.

[0399] Step 2: Using the second influence coefficient calculation model specifically set above, calculate the inlet thickness and roll diameter of each stand corresponding to the finished strip to obtain the influence coefficient of the roll diameter on the forward slip;

[0400] The calculation process is as follows:

[0401] coff(1)=sqrt(dia(1) / (2*then(1)))=sqrt(773.21 / 2 / 40.79))=3.078626;

[0402] coff(2)=sqrt(dia(2) / (2*then(2)))=sqrt(660 / 2 / 22.77))=3.806935;

[0403] coff(3)=sqrt(dia(3) / (2*then(3)))=sqrt(628.24 / 2 / 13.46))=4.830869;

[0404] memory(4)=sqrt(dia(4) / (2*then(4)))=sqrt(649.56 / 2 / 8.75))=6.092431;

[0405] memory(5)=sqrt(dia(5) / (2*then(5)))=sqrt(634.9 / 2 / 6.31))=7.092886;

[0406] memory(6)=sqrt(dia(6) / (2*then(6)))=sqrt(627.51 / 2 / 4.64))=8.223114;

[0407] memory(7)=sqrt(dia(7) / (2*then(7)))=sqrt(655.25 / 2 / 3.6))=9.539756;

[0408] zip roll (1)=(((((r5*memory(1)+r4)*memory(1)+r3)*memory(1)+r2)*memory(1)+r1)*memory(1)+r0=0.777167;

[0409] zip roll (2)=((((r5*memory(2)+r4)*memory(2)+r3)*memory(2)+r2)*memory(2)+r1)*memory(2)+r0=0.832889;

[0410] zip roll (3)=((((r5*memory(3)+r4)*memory(3)+r3)*memory(3)+r2)*memory(3)+r1)*memory(3)+r0=0.886262;

[0411] zip roll (4)=(((((r5*memory(4)+r4)*memory(4)+r3)*memory(4)+r2)*memory(4)+r1)*memory(4)+r0=0.927337;

[0412] zip roll (5)=(((((r5*memory(5)+r4)*memory(5)+r3)*memory(5)+r2)*memory(5)+r1)*memory(5)+r0=0.949632;

[0413] zip roll(6)=((((r5*coff(6)+r4)*coff(6)+r3)*coff(6)+r2)*coff(6)+r1)*coff(6)+r0=0.969765;

[0414] flsip roll (7)=((((r5*coff(7)+r4)*coff(7)+r3)*coff(7)+r2)*coff(7)+r1)*coff(7)+r0=0.989920.

[0415] Step 3: Using the above-specified forward slip coefficient calculation model, calculate the influence coefficient of the reduction rate on the forward slip and the influence coefficient of the roll diameter on the forward slip to obtain the forward slip coefficient of each stand;

[0416] The calculation process is as follows:

[0417] fslip(1)=1+0.92*flsip eps (1)*flsip roll (1) = 1 + 0.92 * 0.108408 * 0.777167 = 1.077511;

[0418] fslip(2)=1+0.92*flsip eps (2)*flsip roll (2) = 1 + 0.92 * 0.104571 * 0.832889 = 1.080129;

[0419] fslip(3)=1+0.92*flsip eps (3)*flsip roll (3) = 1 + 0.92 * 0.094161 * 0.886262 = 1.076775;

[0420] fslip(4)=1+0.92*flsip eps (4)*flsip roll (4) = 1 + 0.92 * 0.076992 * 0.927337 = 1.065686;

[0421] fslip(5)=1+0.92*flsip eps (5)*flsip roll (5) = 1 + 0.92 * 0.072960 * 0.949632 = 1.063742;

[0422] fslip(6)=1+0.92*flsip eps (6)*flsiproll (6) = 1 + 0.92 * 0.062182 * 0.969765 = 1.055478;

[0423] fslip(7)=1+0.92*flsip eps (7)*flsip roll (7) = 1 + 0.92 * 0.044457 * 0.989920 = 1.040488.

[0424] Step 4: Calculate the forward slip coefficient of each rack using the relationship model between the forward slip coefficient and the backward slip coefficient specifically defined above to obtain the backward slip coefficient of each rack;

[0425] The calculation process is as follows:

[0426] bslip(1)=then(2)*fslip(1) / then(1)=22.77*1.077511 / 40.79=0.601494;

[0427] bslip(2)=then(3)*fslip(2) / then(2)=13.46*1.080129 / 22.77=0.638495;

[0428] bslip(3)=then(4)*fslip(3) / then(3)=8.75*1.076775 / 13.46=0.699984;

[0429] bslip(4)=then(5)*fslip(4) / then(4)=6.31*1.065686 / 8.75=0.768512;

[0430] bslip(5)=then(6)*fslip(5) / then(5)=4.64*1.063742 / 6.31=0.782213;

[0431] bslip(6)=then(7)*fslip(6) / then(6)=3.6*1.055478 / 4.64=0.818905;

[0432] bslip(7)=then(8)*fslip(7) / then(7)=3.02*1.040488 / 3.6=0.872854;

[0433] Among them, then(8) represents the outlet thickness of the 7th rack.

[0434] Step 5: Using the above-defined relationship models between the forward slip coefficient and the stand speed, the relationship model between the backward slip coefficient and the stand speed, and the relationship model between the exit speed of the leading stand and the entry speed of the trailing stand, the exit speed of the final finishing stand, the forward slip coefficient, and the backward slip coefficient of each stand are calculated to obtain the entry speed, rolling speed, and exit speed of each stand.

[0435] The calculation process is as follows:

[0436] v(7)=v ex (7) / fslip(7)=8.00 / 1.040488=7.69(m / s);

[0437] v ex (6) = v en (7)=v(7)*bslip(7)=7.69*0.872854=6.71(m / s);

[0438] v(6)=v ex (6) / fslip(6)=6.71 / 1.055478=6.36(m / s);

[0439] v ex (5) = v en (6)=v(6)*bslip(6)=6.36*0.818905=5.21(m / s);

[0440] v(5)=v ex (5) / fslip(5)=5.21 / 1.063742=4.89(m / s);

[0441] v ex (4) = v en (5)=v(5)*bslip(5)=4.89*0.782213=3.83(m / s);

[0442] v(4)=v ex (4) / fslip(4)=3.83 / 1.065686=3.59(m / s);

[0443] v ex (3) = v en (4)=v(4)*bslip(4)=3.59*0.768512=2.76(m / s);

[0444] v(3)=v ex (3) / fslip(3)=2.76 / 1.076775=2.56(m / s);

[0445] v ex (2) = v en (3)=v(3)*bslip(3)=2.56*0.699984=1.79(m / s);

[0446] v(2)=v ex (2) / fslip(2)=1.79 / 1.080129=1.66(m / s);

[0447] v ex (1) = v en (2)=v(2)*bslip(2)=1.66*0.638495=1.06(m / s);

[0448] v(1)=v ex (1) / fslip(1)=1.06 / 1.077511=0.98(m / s);

[0449] v en (1)=v(1)*bslip(1)=0.98*0.601494=0.59(m / s).

[0450] Step 6: Calculate the backslip coefficient of the first finishing stand using the backslip correction coefficients of the different steel grades and the backslip coefficient correction model of the first finishing stand, to obtain a corrected backslip coefficient of the first finishing stand;

[0451] The calculation process is as follows:

[0452] Since the cold rolled material Q195L is rolled in this embodiment, the rough rolling outlet thickness is 40.79 mm, and the finishing rolling target width is 1265 mm, the backslip correction coefficient corr is -0.03;

[0453] The corrected backslip coefficient of the finishing first stand is:

[0454] bslip1(1)=bslip(1)*(1+corr)=0.601494*(1-0.03)=0.583449.

[0455] Step 7, using the relationship model between the backslip coefficient and the stand speed specifically set above, the corrected backslip coefficient of the first finishing stand is calculated to obtain the inlet speed of the first finishing stand;

[0456] The calculation process is as follows:

[0457] v en (1)=v(1)*bslip1(1)=0.98*0.583449=0.57(m / s).

[0458] Step 8, using the above specific setting of the relationship model between the finishing front roller speed and the entrance speed of the first finishing stand, the entrance speed of the first finishing stand is calculated and processed to obtain the finishing front roller speed;

[0459] The calculation process is as follows:

[0460] v roll = v en (1) = 0.57 (m / s).

[0461] According to the above steps, the final roll speed, the front slip coefficient of each stand, the rear slip coefficient and each speed are as follows:

[0462]

[0463]

[0464] Based on the above determined parameters, the finishing rolling is carried out, and the control between stands is stable during rolling, and there is no waist collapse phenomenon before finishing.

[0465] Example 5

[0466] This example rolls high-strength steel, steel roll number: 945022201, steel grade: TQ700MCD; the rough rolling outlet thickness is 41.71mm, the rough rolling outlet width is 1137.4mm; the target thickness of the strip steel finishing rolling is 4.0mm, the target width of the finishing rolling is 1100mm, and the target temperature of the finishing rolling is 880℃.

[0467] The finishing rolling related data are as follows:

[0468] The exit speed of the last finishing stand is 3.99m / s, and the acceleration is 0.026m / s 2 ;

[0469] frame F0 F1 F2 F3 F4 F5 F6 Inlet thickness (mm) 41.71 22.79 13.94 9.36 6.72 5.44 4.6 Export thickness (mm) 22.79 13.94 9.36 6.72 5.44 4.6 4.01 Inlet temperature (℃) 1015.47 994.62 974.02 954.3 935.96 917.6 899.86 Outlet temperature (℃) 994.62 974.02 954.3 935.96 917.6 899.86 880.14 Reduction rate (%) 45.4 38.8 32.9 28.2 19 15.5 12.8 Roller diameter (mm) 772.42 657.74 638.55 606.6 637.35 624.86 668.26

[0470] F0~F6 represent the first stand to the seventh stand.

[0471] Based on the above parameters, the front and rear slip control of the finishing rolling mill is carried out through the following steps:

[0472] Step 1, using the above specific setting of the first influence coefficient calculation model, the reduction rate of each stand corresponding to the strip steel to be finished is calculated and processed to obtain the influence coefficient of the reduction rate on the front slip;

[0473] The calculation process is as follows:

[0474] flsip eps(1)=((((e5*eps(1)+e4)*eps(1)+e3)*eps(1)+e2)*eps(1)+e1)*eps(1)+e0=0.109432;

[0475] flsip eps (2)=((((e5*eps(2)+e4)*eps(2)+e3)*eps(2)+e2)*eps(2)+e1)*eps(2)+e0=0.101362;

[0476] flsip eps (3)=((((e5*eps(3)+e4)*eps(3)+e3)*eps(3)+e2)*eps(3)+e1)*eps(3)+e0=0.089508;

[0477] flsip eps (4)=((((e5*eps(4)+e4)*eps(4)+e3)*eps(4)+e2)*eps(4)+e1)*eps(4)+e0=0.077787;

[0478] flsip eps (5)=((((e5*eps(5)+e4)*eps(5)+e3)*eps(5)+e2)*eps(5)+e1)*eps(5)+e0=0.052426;

[0479] flsip eps (6)=((((e5*eps(6)+e4)*eps(6)+e3)*eps(6)+e2)*eps(6)+e1)*eps(6)+e0=0.042829;

[0480] flsip eps (7)=((((e5*eps(7)+e4)*eps(7)+e3)*eps(7)+e2)*eps(7)+e1)*eps(7)+e0=0.035597.

[0481] Step 2: Using the second influence coefficient calculation model specifically set above, calculate the inlet thickness and roll diameter of each stand corresponding to the finished strip to obtain the influence coefficient of the roll diameter on the forward slip;

[0482] The calculation process is as follows:

[0483] memory(1)=sqrt(dia(1) / (2*then(1)))=sqrt(772.42 / 2 / 41.71))=3.042928;

[0484] memory(2)=sqrt(dia(2) / (2*then(2)))=sqrt(657.74 / 2 / 22.79))=3.798743;

[0485] memory(3)=sqrt(dia(3) / (2*then(3)))=sqrt(638.55 / 2 / 13.94))=4.785762;

[0486] memory(4)=sqrt(dia(4) / (2*then(4)))=sqrt(606.6 / 2 / 9.36))=5.692438;

[0487] memory(5)=sqrt(dia(5) / (2*then(5)))=sqrt(637.35 / 2 / 6.72))=6.886354;

[0488] memory(6)=sqrt(dia(6) / (2*then(6)))=sqrt(624.86 / 2 / 5.44))=7.578389;

[0489] memory(7)=sqrt(dia(7) / (2*then(7)))=sqrt(668.26 / 2 / 4.6))=8.522732;

[0490] zip roll (1)=(((((r5*memory(1)+r4)*memory(1)+r3)*memory(1)+r2)*memory(1)+r1)*memory(1)+r0=0.773946;

[0491] zip roll (2)=((((r5*memory(2)+r4)*memory(2)+r3)*memory(2)+r2)*memory(2)+r1)*memory(2)+r0=0.832358;

[0492] zip roll (3)=((((r5*memory(3)+r4)*memory(3)+r3)*memory(3)+r2)*memory(3)+r1)*memory(3)+r0=0.884376;

[0493] ziproll (4)=((((r5*coff(4)+r4)*coff(4)+r3)*coff(4)+r2)*coff(4)+r1)*coff(4)+r0=0.916355;

[0494] flsip roll (5)=((((r5*coff(5)+r4)*coff(5)+r3)*coff(5)+r2)*coff(5)+r1)*coff(5)+r0=0.945487;

[0495] flsip roll (6)=((((r5*coff(6)+r4)*coff(6)+r3)*coff(6)+r2)*coff(6)+r1)*coff(6)+r0=0.958725;

[0496] flsip roll (7)=((((r5*coff(7)+r4)*coff(7)+r3)*coff(7)+r2)*coff(7)+r1)*coff(7)+r0=0.974601.

[0497] Step 3: Using the above-specified forward slip coefficient calculation model, calculate the influence coefficient of the reduction rate on the forward slip and the influence coefficient of the roll diameter on the forward slip to obtain the forward slip coefficient of each stand;

[0498] The calculation process is as follows:

[0499] fslip(1)=1+0.92*flsip eps (1)*flsip roll (1) = 1 + 0.92 * 0.109432 * 0.773946 = 1.077919;

[0500] fslip(2)=1+0.92*flsip eps (2)*flsip roll (2) = 1 + 0.92 * 0.101362 * 0.832358 = 1.077620;

[0501] fslip(3)=1+0.92*flsip eps (3)*flsip roll (3) = 1 + 0.92 * 0.089508 * 0.884376 = 1.072826;

[0502] fslip(4)=1+0.92*flsipeps (4)*flsip roll (4) = 1 + 0.92 * 0.077787 * 0.916355 = 1.065578;

[0503] fslip(5)=1+0.92*flsip eps (5)*flsip roll (5) = 1 + 0.92 * 0.052426 * 0.945487 = 1.045603;

[0504] fslip(6)=1+0.92*flsip eps (6)*flsip roll (6) = 1 + 0.92 * 0.042829 * 0.958725 = 1.037776;

[0505] fslip(7)=1+0.92*flsip eps (7)*flsip roll (7)=1+0.92*0.035597*0.974601=1.031917.

[0506] Step 4: Calculate the forward slip coefficient of each rack using the relationship model between the forward slip coefficient and the backward slip coefficient specifically defined above to obtain the backward slip coefficient of each rack;

[0507] The calculation process is as follows:

[0508] bslip(1)=then(2)*fslip(1) / then(1)=22.79*1.077919 / 41.71=0.588966;

[0509] bslip(2)=then(3)*fslip(2) / then(2)=13.94*1.077620 / 22.79=0.659150;

[0510] bslip(3)=then(4)*fslip(3) / then(3)=9.36*1.072826 / 13.94=0.720348;

[0511] bslip(4)=then(5)*fslip(4) / then(4)=6.72*1.065578 / 9.36=0.765030;

[0512] bslip(5)=then(6)*fslip(5) / then(5)=5.44*1.045603 / 6.72=0.846440;

[0513] bslip(6)=then(7)*fslip(6) / then(6)=4.6*1.037776 / 5.44=0.877531;

[0514] bslip(7)=then(8)*fslip(7) / then(7)=4.01*1.031917 / 4.6=0.899563;

[0515] Among them, then(8) represents the outlet thickness of the 7th rack.

[0516] Step 5: Using the above-defined relationship models between the forward slip coefficient and the stand speed, the relationship model between the backward slip coefficient and the stand speed, and the relationship model between the exit speed of the leading stand and the entry speed of the trailing stand, the exit speed of the final finishing stand, the forward slip coefficient, and the backward slip coefficient of each stand are calculated to obtain the entry speed, rolling speed, and exit speed of each stand.

[0517] The calculation process is as follows:

[0518] v(7)=3.87(m / s); v ex (6)=3.48(m / s); v(6)=3.35(m / s); v ex (5)=2.94(m / s); v(5)=2.81(m / s);

[0519] v ex (4)=2.38(m / s); v(4)=2.23(m / s); v ex (3)=1.71(m / s); v(3)=1.59(m / s); v ex (2) = 1.15 (m / s);

[0520] v(2)=1.07(m / s);v ex (1)=0.70(m / s); v(1)=0.65(m / s); v en (1) = 0.38 (m / s).

[0521] Step 6: Calculate the backslip coefficient of the first finishing stand using the backslip correction coefficients of the different steel grades and the backslip coefficient correction model of the first finishing stand, to obtain a corrected backslip coefficient of the first finishing stand;

[0522] The calculation process is as follows:

[0523] Since this embodiment rolls high-strength steel, the rough rolling outlet thickness is 41.71 mm, and the finishing rolling target width is 1100 mm, the backslip correction coefficient corr is set to 0;

[0524] The corrected backslip coefficient of the finishing first stand is:

[0525] bslip1(1)=bslip(1)*(1+corr)=0.568009*(1-0)=0.568009.

[0526] Step 7, using the relationship model between the backslip coefficient and the stand speed specifically set above, the corrected backslip coefficient of the first finishing stand is calculated to obtain the inlet speed of the first finishing stand;

[0527] The calculation process is as follows:

[0528] v en (1)=v(1)*bslip1(1)=0.65*0.568009=0.38(m / s).

[0529] Step 8: using the relationship model between the roller speed before finishing rolling and the inlet speed of the first finishing stand specifically set above, the inlet speed of the first finishing stand is calculated to obtain the roller speed before finishing rolling;

[0530] The calculation process is as follows:

[0531] v roll =v en (1) = 0.38 (m / s).

[0532] According to the above steps, the final roller speed, forward slip coefficient, backward slip coefficient and speed of each frame are as follows:

[0533] frame roll F0 F1 F2 F3 F4 F5 F6 fslip 1.077919 1.077620 1.072826 1.065578 1.045603 1.037776 1.031917 bslip 0.588966 0.659150 0.720348 0.765030 0.846440 0.877531 0.899563 <![CDATA[v en ]]> 0.38 0.70 1.15 1.71 2.38 2.94 3.48 v 0.65 1.07 1.59 2.23 2.81 3.35 3.87 v ex ]]> 0.70 1.15 1.71 2.38 2.94 3.48 3.99 <![CDATA[v roll ]]> 0.38

[0534] Finish rolling is carried out based on the various parameters determined above. During the rolling process, the control between stands is stable and there is no waist collapse phenomenon before finish rolling.

[0535] It can be seen that the forward and backward sliding control method of the finishing rolling mill provided by the embodiment of the present invention can ensure the consistency control of the second flow rate between frames, improve the rolling stability between frames, avoid the collapse of soft steel grades in front of the finishing mill, and improve the surface quality of soft steel grades.

[0536] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In addition, "front", "back", "left", "right", "upper" and "lower" in this document are all referenced to the placement states shown in the accompanying drawings.

[0537] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for controlling the forward and backward sliding of a finishing mill, characterized in that: include: Using the preset first influence coefficient calculation model, the reduction ratio of each stand corresponding to the finished strip is calculated and processed to obtain the influence coefficient of the reduction ratio on the forward slip; Using the preset second influence coefficient calculation model, the inlet thickness and roll diameter of each stand corresponding to the finished strip are calculated and processed to obtain the influence coefficient of the roll diameter on the forward slip; Using the preset forward slip coefficient calculation model, the influence coefficients of the reduction rate and the roll diameter on the forward slip are calculated and processed to obtain the forward slip coefficients of each stand; Using a preset relationship model between the forward slip coefficient and the backward slip coefficient, the forward slip coefficient of each rack is calculated to obtain the backward slip coefficient of each rack; Using the preset relationship model between the forward slip coefficient and the stand speed, the relationship model between the backward slip coefficient and the stand speed, and the relationship model between the exit speed of the front stand and the entry speed of the rear stand, the exit speed of the final stand of the finishing rolling mill, the forward slip coefficient and the backward slip coefficient of each stand are calculated and processed to obtain the entry speed, rolling speed and exit speed of each stand; Utilizing preset backslip correction coefficients for different steel grades and a preset backslip correction model for the finishing first stand, the backslip coefficient of the finishing first stand is calculated and processed to obtain a corrected backslip coefficient of the finishing first stand; Using the preset relationship model between the backslip coefficient and the stand speed, the corrected backslip coefficient of the first stand of the finishing mill is calculated to obtain the inlet speed of the first stand of the finishing mill; The preset relationship model between the roller speed before finishing rolling and the inlet speed of the first finishing stand is used to calculate the inlet speed of the first finishing stand to obtain the roller speed before finishing rolling.

2. The method for controlling the forward and backward sliding of the finishing mill according to claim 1, characterized in that: The calculation model expression of the first influence coefficient is: flsip eps (i)=((((e5*eps(i)+e4)*eps(i)+e3)*eps(i)+e2)*eps(i)+e1)*eps(i)+e0; Among them, i represents the rack number identification, flsip eps (i) represents the influence coefficient of the reduction rate corresponding to the i-th rack on the forward slip, eps(i) represents the reduction rate of the i-th rack, and e5, e4, e3, e2, e1 and e0 represent the reduction rate coefficients.

3. The method for controlling the forward and backward sliding of the finishing mill according to claim 2, characterized in that: The reduction coefficient is set to: 。 4. The method for controlling the forward and backward sliding of the finishing mill according to claim 1, characterized in that: The calculation model expression of the second influence coefficient is: zip roll (i)=(((((r5*memory(i)+r4)*memory(i)+r3)*memory(i)+r2)*memory(i)+r1)*memory(i)+r0; Among them, i represents the rack number identification, flsip roll (i) represents the influence coefficient of the roller diameter corresponding to the i-th stand on the forward slip, r5, r4, r3, r2, r1 and r0 represent the roller diameter coefficients, coff(i) represents the intermediate calculation coefficient corresponding to the i-th stand, and the intermediate calculation coefficient coff(i) is expressed as: coff(i)=sqrt(dia(i) / (2*then(i))); Where i is the rack number, dia(i) is the roll diameter of the i-th rack, then(i) is the inlet thickness of the i-th rack, and sqrt is the square root calculation.

5. The method for controlling the forward and backward sliding of the finishing mill according to claim 4, characterized in that: The roller diameter coefficient is set as: 。 6. The method for controlling the forward and backward sliding of the finishing mill according to claim 1, characterized in that: The forward slip coefficient calculation model expression is: fslip(i)=1+0.92*flsip eps (i)*flsip roll (i); Among them, i represents the rack number, fslip(i) represents the forward slip coefficient of the i-th rack, flsip eps (i) represents the influence coefficient of the pressure reduction rate corresponding to the i-th rack on the forward slip, flsip roll (i) represents the influence coefficient of the roll diameter corresponding to the i-th stand on the forward slip.

7. The method for controlling the forward and backward sliding of the finishing mill according to claim 1, characterized in that: The relationship model expression between the forward slip coefficient and the backward slip coefficient is: bslip(i)=then(i+1)*fslip(i) / then(i); Where i represents the rack number, bslip(i) represents the backslip coefficient of the i-th rack, fslip(i) represents the forward slip coefficient of the i-th rack, then(i+1) represents the inlet thickness of the i+1-th rack, and then(i) represents the inlet thickness of the i-th rack.

8. The method for controlling the forward and backward sliding of the finishing mill according to claim 1, characterized in that: The relationship model expression between the forward slip coefficient and the frame speed is: v(i)=v ex (i) / fslip(i); The relationship model expression between the backslip coefficient and the rack speed is: v en (i)=v(i)*bslip(i); The relationship model expression between the outlet velocity of the front rack and the inlet velocity of the rear rack is: v ex (i)=v en (i+1); Where i represents the stand number, v(i) represents the rolling speed of the i-th stand, and v ex (i) represents the exit speed of the i-th rack, fslip(i) represents the forward slip coefficient of the i-th rack, v en (i) represents the inlet velocity of the i-th rack, bslip(i) represents the backslip coefficient of the i-th rack, v en (i+1) represents the inlet velocity of the i+1th rack.

9. The method for controlling the forward and backward sliding of the finishing mill according to claim 1, characterized in that: The backslip correction coefficients for different steel grades are set as: When the backslip correction coefficient is a range value, the backslip correction coefficient includes the lower boundary value and excludes the upper boundary value; The correction model expression of the back slip coefficient of the first stand of finishing rolling is: bslip1(1)=bslip(1)*(1+corr); Among them, bslip1(1) represents the backslip coefficient of the first stand of finishing rolling after correction, bslip(1) represents the backslip coefficient of the first stand of finishing rolling before correction, and corr represents the backslip correction coefficient.

10. The method for controlling the forward and backward sliding of the finishing mill according to claim 1, characterized in that: The relationship model expression between the roller speed before finishing and the entrance speed of the first stand of finishing is: v roll =v en (1); Among them, v roll Indicates the roller speed before finishing rolling, v en (1) Indicates the inlet speed of the finishing mill head.

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