US 12,083,569 B2
Meandering control method for hot-rolled steel strip, meandering control device, and hot rolling equipment
Tatsuhiro Sue, Tokyo (JP); Yukio Takashima, Tokyo (JP); Hiroto Goto, Tokyo (JP); Hideto Yamaguchi, Tokyo (JP); and Shohei Nishi, Tokyo (JP)
Assigned to JFE Steel Corporation, Tokyo (JP)
Appl. No. 17/617,631
Filed by JFE Steel Corporation, Tokyo (JP)
PCT Filed Jun. 11, 2020, PCT No. PCT/JP2020/023098
§ 371(c)(1), (2) Date Dec. 9, 2021,
PCT Pub. No. WO2020/255863, PCT Pub. Date Dec. 24, 2020.
Claims priority of application No. 2019-114684 (JP), filed on Jun. 20, 2019; and application No. 2020-085279 (JP), filed on May 14, 2020.
Prior Publication US 2022/0241832 A1, Aug. 4, 2022
Int. Cl. B21B 37/68 (2006.01); B21B 1/26 (2006.01); B21B 37/58 (2006.01)
CPC B21B 37/68 (2013.01) [B21B 1/26 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A meandering control method for a hot-rolled steel strip, the method controlling meandering of the hot-rolled steel strip rolled in finish rolling equipment including n (n≥3) rolling machines each of the rolling machines having a load detector configured to detect rolling loads on an operation side and a driving side and a leveling device configured to adjust rolling amounts on the operation side and the driving side, the method comprising:
a meandering amount measurement step of measuring a meandering amount of a traveling hot-rolled steel strip by a meandering amount measuring device installed between an i-th (i≥n) rolling machine and an (i−1)th rolling machine counting from a rolling machine installed on a most upstream side;
a differential load detection step of detecting a differential load between the operation side and the driving side from the rolling loads on the operation side and the driving side detected by the load detector provided in the i-th rolling machine; and
a leveling control computation step of computing a roll opening degree difference based on the meandering amount of the hot-rolled steel strip measured in the meandering amount measurement step and the differential load detected in the differential load detection step, the roll opening degree difference being an opening degree difference of roll gaps between the operation side and the driving side in the i-th rolling machine, and sending the computed roll opening degree difference to the leveling device provided in the i-th rolling machine,
wherein the roll opening degree difference computed in the leveling control computation step, the roll opening degree difference being the opening degree difference of the roll gaps between the operation side and the driving side in the i-th rolling machine, satisfies the roll opening degree difference between the operation side and the driving side in the i-th rolling machine by Expressions (1), (2), and (3) in a control section j, when the control section j is set when a tail end portion of the traveling hot-rolled steel strip is present between a j-th (j≤i−1) rolling machine and a (j+1)th rolling machine counting from the rolling machine installed on the most upstream side,
S=αjC(δ−δj)+βjD(ΔP−ΔPj)+Sj  (1)
0≤α1≤α2≤ . . . ≤αj≤ . . . ≤αi−1  (2)
0≤β1≤β2≤ . . . ≤βj≤ . . . ≤βi−1  (3)
wherein S is the roll opening degree difference between the operation side and the driving side in the i-th rolling machine, Sj is the roll opening degree difference between the operation side and the driving side in the i-th rolling machine when the tail end portion of the hot-rolled steel strip has passed through the j-th rolling machine, αj is a control gain with respect to the meandering amount measured by the meandering amount measuring device, in the control section j, βj is a control gain with respect to the differential load detected from the load detector provided in the i-th rolling machine, in the control section j, δj is the meandering amount measured by the meandering amount measuring device when the tail end portion of the hot-rolled steel strip has passed through the j-th rolling machine, δPj is the differential load detected from the load detector provided in the i-th rolling machine when the tail end portion of the hot-rolled steel strip has passed through the j-th rolling machine, δ is the meandering amount measured by the meandering amount measuring device, in the control section j, ΔP is the differential load detected from the load detector provided in the i-th rolling machine, in the control section j, C is a change amount of a leveling amount with respect to the meandering amount, and D is a constant determined by a roll diameter, a roll length, number of rolls or a width of a rolling material.
 
7. A meandering control device for a hot-rolled steel strip, the device being configured to control meandering of the hot-rolled steel strip rolled in finish rolling equipment including n (n≥3) rolling machines each of the rolling machines having a load detector configured to detect rolling loads on an operation side and a driving side and a leveling device configured to adjust rolling amounts on the operation side and the driving side, the device comprising:
a meandering amount measuring device installed between an i-th (i≤n) rolling machine and an (i−1)th rolling machine counting from a rolling machine installed on a most upstream side, and configured to measure a meandering amount of a traveling hot-rolled steel strip; and
a leveling control computing device configured to compute a roll opening degree difference based on the meandering amount of the hot-rolled steel strip measured by the meandering amount measuring device and a differential load between the operation side and the driving side detected from the rolling loads on the operation side and the driving side detected by the load detector provided in the i-th rolling machine, the roll opening degree difference being an opening degree difference of roll gaps between the operation side and the driving side in the i-th rolling machine, and to send the computed roll opening degree difference to the leveling device provided in the i-th rolling machine,
wherein the roll opening degree difference computed by the leveling control computing device, the roll opening degree difference being the opening degree difference of the roll gaps between the operation side and the driving side in the i-th rolling machine, satisfies the roll opening degree difference between the operation side and the driving side in the i-th rolling machine by Expressions (1), (2), and (3) in a control section j, in a case where the control section j is set when a tail end portion of the traveling hot-rolled steel strip is present between a j-th (j≤i−1) rolling machine and a (j+1)th rolling machine counting from the rolling machine installed on the most upstream side,
S=αjC(δ−δj)+βjD(ΔP−ΔPj)+Sj  (1)
0≤α1≤α2≤ . . . ≤αj≤ . . . ≤αi−1  (2)
0≤β1≤β2≤ . . . ≤βj≤ . . . ≤βi−1  (3)
wherein S is the roll opening degree difference between the operation side and the driving side in the i-th rolling machine, Sj is the roll opening degree difference between the operation side and the driving side in the i-th rolling machine when the tail end portion of the hot-rolled steel strip has passed through the j-th rolling machine, αj is a control gain with respect to the meandering amount measured by the meandering amount measuring device, in the control section j, βj is a control gain with respect to the differential load detected from the load detector provided in the i-th rolling machine, in the control section j, δj is the meandering amount measured by the meandering amount measuring device when the tail end portion of the hot-rolled steel strip has passed through the j-th rolling machine, ΔPj is the differential load detected from the load detector provided in the i-th rolling machine when the tail end portion of the hot-rolled steel strip has passed through the j-th rolling machine, δ is the meandering amount measured by the meandering amount measuring device, in the control section j, ΔP is the differential load detected from the load detector provided in the i-th rolling machine, in the control section j, C is a change amount of a leveling amount with respect to the meandering amount, and D is a constant determined by a roll diameter, a roll length, the number of rolls, a width of a rolling material.