Rolling width control method based on continuous optimization side pressure strategy

Abstract

The invention discloses a rolling width control method based on a continuous optimization side pressure strategy, which comprises the following steps: by taking steel grades, blank thickness, blank width, finished product thickness and total side pressure quantity as indexes, respectively presetting various maximum side pressure quantity valuing strategies for each type of steel grade; the method comprises the following steps: before rough rolling, selecting a maximum side pressure value strategy from a plurality of preset maximum side pressure value strategies according to a steel type, an actual side pressure requirement and a rough rolling width requirement, and determining the number of rolling passes and the side pressure of each pass according to the selected maximum side pressure value strategy; and in the rough rolling process, based on the selected rolling pass number and the side pressure amount of each pass, the side pressure amount of the subsequent pass is corrected and adjusted according to the actual rough rolling width measured after rolling of the previous pass. According to the method, the rolling width control precision can be improved, the ultra-width and width negative proportion can be greatly reduced, and the finished product yield is remarkably improved.

Description

Technical Field

[0001] The invention relates to the technical field of steel rolling, and in particular to a rolling width control method based on a continuous optimization side pressure strategy. Background Art

[0002] refer to Figure 1 The existing 1549mm hot rolling production line includes a furnace area, a rough rolling area, a finishing rolling area, a laminar cooling area and a coiling area arranged in sequence. The furnace area includes 4 heating furnaces arranged in sequence. The rough rolling area includes a high-pressure water descaling box, a rough rolling vertical roll mill (VE0), a rough rolling flat roll mill (R0) and an insulation cover arranged in sequence. The finishing rolling area includes a rotary drum head 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 arranged with laminar cooling equipment, and the coiling area is arranged with two coilers (C1, C2). The hot rolling process based on the 1549mm hot rolling production line is a production method for producing steel coils. It usually uses continuous casting slabs or initial rolled slabs as raw materials. The production process mainly includes that the slabs are first heated in a heating furnace according to the temperature specified by the process to the target temperature; then they are descaled by high-pressure water and then enter the roughing mill for rolling, wherein the roughing vertical roll controls the width and the roughing flat roll controls the thickness. Reversible rolling is performed in the roughing unit, generally for 5 to 7 passes; after rolling in the roughing unit, the strip reaches the preset target thickness, width and temperature, and then enters the finishing unit for seven-stand flat roll continuous rolling to achieve the preset target thickness, temperature, convexity and flatness; then the strip is controlled by laminar cooling to reach the target coiling temperature; finally, the strip is formed into a steel coil by a coiler.

[0003] In the hot rolling process, width control is one of the most important control indicators. If the width of the finished product is too narrow, it will directly cause the user to be unable to use it and become waste; if it is too wide, the user's yield rate will decrease due to the increased trimming amount during use. Therefore, width control accuracy is an important control indicator for the hot rolling process. In the existing 1549mm hot rolling production line, the only equipment for width control is the rough rolling vertical roll, so the width control accuracy is guaranteed by the calculation accuracy of the vertical roll side pressure.

[0004] At present, for the 1549mm hot rolling production line, the width side pressure control usually adopts the following methods:

[0005] 1) Determine the target width of finishing rolling according to the steel type and target width of finishing rolling;

[0006] Specifically, the width control is based on positive tolerance control, the finishing target width is the minimum width required by the user, and the finishing control target width is the sum of the finishing target width and the tolerance median. For example, if the finishing target width is 1250mm and the tolerance requirement is 0-20mm, then the finishing target control width is 1250+(20-0) / 2=1260mm.

[0007] 2) Determine the target width of rough rolling according to the target width of finishing rolling and the calculated width of finishing rolling;

[0008] Specifically, the rough rolling target width = the finishing rolling control target width - the finishing rolling calculated width.

[0009] 3) Calculate the side pressure for each pass according to the target width of rough rolling;

[0010] Specifically, in rough rolling, rough rolling is divided into two rolling modes: 5 passes and 7 passes. Only the vertical rolls in odd passes are rolled with side pressure, and the side pressure in even passes is released, without side pressure, and no control is performed. Therefore, when the rough rolling is 5 passes, the 1st, 3rd, and 5th passes are rolled with side pressure, and the 2nd and 4th passes are rolled without side pressure; when the rough rolling is 7 passes, the 1st, 3rd, 5th, and 7th passes are rolled with side pressure, and the 2nd, 4th, and 6th passes are rolled without side pressure.

[0011] The calculation of the side pressure of each rough rolling pass is based on the rough rolling target width (the correction value can be added according to the steel type for each pass). The specific calculation strategy is as follows:

[0012] The first pass side pressure is calculated based on the target width of rough rolling - the first pass flat roll width - the first pass dog bone width - the second pass flat roll width, that is, the first pass side pressure is calculated based on the target width of rough rolling at the second pass exit.

[0013] The side pressure of the third pass is calculated based on the target width of rough rolling - the width of the flat roll of the third pass - the width of the dog bone of the third pass - the width of the flat roll of the fourth pass. That is, the side pressure of the third pass is calculated based on the target width of rough rolling at the exit of the fourth pass.

[0014] The side pressure of the 5th pass is calculated in the following two cases: when the rough rolling is 5 passes, the side pressure of the 5th pass is calculated with the target of "rough rolling target width - 5th pass flat roll width - 5th pass dog bone width", that is, the side pressure of the 5th pass is calculated with the target width of the 5th pass outlet reaching the target width of rough rolling; when the rough rolling is 7 passes, the side pressure of the 5th pass is calculated with the target width of rough rolling - 5th pass flat roll width - 5th pass dog bone width - 6th pass flat roll width", that is, the side pressure of the 5th pass is calculated with the target width of the 6th pass outlet reaching the target width of rough rolling;

[0015] The side pressure of the 7th pass is calculated based on the "roughing target width - 7th pass flat roll width - 7th pass dog bone width", that is, the side pressure of the 7th pass is calculated based on the 7th pass outlet width reaching the roughing target width.

[0016] During the rough rolling process, with lateral pressure control, the smaller the lateral pressure, the smaller the risk. On the one hand, when the lateral pressure is small, the width shape of the head and tail is regular, and the overall plate shape is good; on the other hand, when the lateral pressure increases, the probability of scrap steel such as steel bending and slipping will increase accordingly. Some steel types such as silicon steel and cold-rolled materials will be scratched due to excessive dog bones or excessive lateral pressure. Therefore, during the rough rolling control process, each pass is limited by the maximum lateral pressure. At the same time, the maximum lateral pressure also plays a role in distributing the load of the vertical roller. For example, when the maximum lateral pressure distributed in the first pass is small, the vertical roller load will automatically increase and distribute to the third pass. Among them, the maximum lateral pressure is implemented according to the following strategies:

[0017] When the calculation exceeds the maximum lateral pressure, it shall be executed according to the maximum lateral pressure;

[0018] Whenever possible, the maximum lateral pressure should be as small as possible.

[0019] 4) When designing the pass strategy, 5-pass rolling is given priority. Only when 5-pass rolling cannot meet the width requirements, 7-pass rolling is used.

[0020] However, in the actual rolling control process, the above width side pressure control strategy still has the following problems:

[0021] When the steel type, specification and total side pressure remain unchanged, the number of rough rolling passes and the maximum side pressure of each pass are fixed values. During the rolling process, the composition, temperature and other factors of the strip are constantly changing, resulting in the deformation resistance and actual width of the strip in the rough rolling stand. When the current side pressure cannot meet the width control, it can only be rolled according to the maximum side pressure of the current pass, resulting in the frequent occurrence of the maximum side pressure cannot meet the width control accuracy during the calculation process, and the over-width phenomenon is common. Due to the different thickness of the finished product, the width is also different, and the current side pressure determination does not consider the influence of the thickness of the finished product. There is no correction calculation between passes, that is, after the current pass is completed, if there is a deviation between the actual width and the calculated width, no correction is performed in the subsequent pass, resulting in a significant impact on the width accuracy, and the over-width and negative width phenomena cannot be compensated in time in the subsequent pass control. Summary of the invention

[0022] In order to solve part or all of the technical problems existing in the above-mentioned prior art, the present invention provides a rolling width control method based on continuous optimization of side pressure strategy.

[0023] The technical solution of the present invention is as follows:

[0024] A rolling width control method based on continuous optimization of side pressure strategy is provided, the method comprising:

[0025] With steel type, billet thickness, billet width, finished product thickness and total side pressure as indexes, multiple maximum side pressure value strategies are preset for each type of steel type;

[0026] Before rough rolling, according to the steel type, actual side pressure requirement and rough rolling width requirement, a maximum side pressure value strategy is selected from multiple preset maximum side pressure value strategies, and the number of rolling passes and the side pressure amount of each pass are determined according to the selected maximum side pressure value strategy;

[0027] During the rough rolling process, based on the selected number of rolling passes and the side pressure of each pass, the side pressure of the subsequent pass is corrected and adjusted according to the actual rough rolling width measured after the previous pass.

[0028] In some optional implementations, four maximum lateral pressure value strategies are preset for each type of steel.

[0029] In some optional embodiments, steel type, billet thickness, billet width, finished product thickness, and total lateral pressure are used as indexes, and each index corresponds to 4 plan numbers, each plan number corresponds to a maximum lateral pressure value strategy, and the 4 plan numbers correspond to four maximum lateral pressure value strategies, and each plan number includes the number of passes and the maximum lateral pressure of each pass.

[0030] In some optional implementations, the plan number value corresponding to each steel grade is set to:

[0031]

[0032]

[0033] The number of passes corresponding to each plan number and the maximum lateral pressure value of each pass are set as follows:

[0034]

[0035]

[0036] When the value of the total lateral pressure is a range value, the value of the total lateral pressure includes the lower boundary value but does not include the upper boundary value.

[0037] In some optional implementations, when selecting a maximum lateral pressure value strategy from a plurality of preset maximum lateral pressure value strategies, firstly calculate according to the first maximum lateral pressure value strategy, if the first maximum lateral pressure value strategy can meet the width requirement, then the first maximum lateral pressure value strategy is selected, if the first maximum lateral pressure value strategy cannot meet the width requirement, then calculate according to the second maximum lateral pressure value strategy;

[0038] If the second maximum lateral pressure value selection strategy can meet the width requirement, the second maximum lateral pressure value selection strategy is selected; if the second maximum lateral pressure value selection strategy cannot meet the width requirement, the third maximum lateral pressure value selection strategy is used for calculation;

[0039] If the third maximum lateral pressure value taking strategy can meet the width requirement, then the third maximum lateral pressure value taking strategy is selected; if the third maximum lateral pressure value taking strategy cannot meet the width requirement, then the fourth maximum lateral pressure value taking strategy is selected.

[0040] In some optional implementations, when a maximum side pressure value strategy is selected from a plurality of preset maximum side pressure value strategies, the calculation result of the rough rolling last pass outlet width is determined according to the number of passes and the maximum side pressure in the first maximum side pressure value strategy. When the calculated value of the rough rolling last pass outlet width minus the rough rolling last pass outlet width target value ≤ 3 mm, it is determined that the width requirement is met and the first maximum side pressure value strategy is selected. Otherwise, it is determined that the width requirement is not met and the next step is executed.

[0041] According to the number of passes and the maximum side pressure in the second maximum side pressure value selection strategy, the calculation result of the rough rolling final pass outlet width is determined. When the calculated value of the rough rolling final pass outlet width minus the rough rolling final pass outlet width target value is ≤3mm, it is determined that the width requirement is met and the second maximum side pressure value selection strategy is selected. Otherwise, it is determined that the width requirement is not met and the next step is executed.

[0042] According to the number of passes and the maximum side pressure in the third maximum side pressure value selection strategy, the calculation result of the rough rolling last pass outlet width is determined. When the calculated value of the rough rolling last pass outlet width minus the rough rolling last pass outlet width target value is ≤3mm, it is determined that the width requirement is met and the third maximum side pressure value selection strategy is selected. Otherwise, it is determined that the width requirement is not met and the next step is executed.

[0043] The calculation result of the width of the last roughing pass outlet is determined according to the number of passes and the maximum side pressure in the fourth maximum side pressure value taking strategy. When the calculated value of the width of the last roughing pass outlet minus the target value of the width of the last roughing pass outlet is ≤3mm, it is determined that the width requirement is met and the fourth maximum side pressure value taking strategy is selected. Otherwise, it is determined that the width requirement is not met and the fourth maximum side pressure value taking strategy is still selected.

[0044] In some optional implementations, the side pressure of the subsequent pass is corrected and adjusted according to the actual rough rolling width measured after the previous pass rolling, including:

[0045] After each odd pass is rolled, the width of the current odd pass is measured using a width gauge at the rough rolling exit. The average width of the first 1 / 3 of the strip at the current odd pass exit is used as the current odd pass exit width. The current odd pass exit width is used as the width reference for calculating the lateral pressure, and the lateral pressure of subsequent passes is corrected and adjusted.

[0046] The main advantages of the technical solution of the present invention are as follows:

[0047] The rolling width control method based on the continuous optimization of the side pressure strategy of the present invention presets a plurality of maximum side pressure value strategies for each type of steel, and continuously corrects the selected side pressure according to the actual rolling conditions of the strip. It can obtain the side pressure corresponding to the highest width control accuracy on the basis of considering the side pressure to be as small as possible, thereby improving the rolling width control accuracy. Under the premise of ensuring rolling stability and equipment safety, it can achieve the purpose of greatly improving the width control accuracy through continuous optimization of the pass number and the side pressure amount, can greatly reduce the over-width and negative width ratio, and significantly improve the finished product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The 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. In the drawings:

[0049] Figure 1 This is a schematic diagram of the equipment layout of an existing 1549mm hot rolling production line;

[0050] Figure 2 A flow chart of a rolling width control method based on continuous optimization of side pressure strategy provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the 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 work are within the scope of protection of the present invention.

[0052] The technical solution provided by the embodiments of the present invention is described in detail below with reference to the accompanying drawings.

[0053] refer to Figure 2 The embodiment of the present invention provides a rolling width control method based on the continuous optimization side pressure strategy, which is used in a 1549mm hot rolling production line, and includes the following steps:

[0054] With steel type, billet thickness, billet width, finished product thickness and total side pressure as indexes, multiple maximum side pressure value strategies are preset for each type of steel type;

[0055] Before rough rolling, according to the steel type, actual side pressure requirement and rough rolling width requirement, a maximum side pressure value strategy is selected from multiple preset maximum side pressure value strategies, and the number of rolling passes and the side pressure amount of each pass are determined according to the selected maximum side pressure value strategy;

[0056] During the rough rolling process, based on the selected number of rolling passes and the side pressure of each pass, the side pressure of the subsequent pass is corrected and adjusted according to the actual rough rolling width measured after the previous pass.

[0057] The rolling width control method based on the continuous optimization of the side pressure strategy provided by the embodiment of the present invention presets a plurality of maximum side pressure value strategies for each type of steel, and continuously corrects the selected side pressure according to the actual rolling conditions of the strip. It can obtain the side pressure corresponding to the highest width control accuracy on the basis of considering the side pressure to be as small as possible, thereby improving the rolling width control accuracy. Under the premise of ensuring rolling stability and equipment safety, it can achieve the purpose of greatly improving the width control accuracy through continuous optimization of the pass number and the side pressure amount, can greatly reduce the over-width and negative width ratio, and significantly improve the finished product yield.

[0058] Furthermore, in the embodiment of the present invention, four maximum lateral pressure value selection strategies are preset for each type of steel.

[0059] Specifically, in an embodiment of the present invention, steel type, billet thickness, billet width, finished product thickness, and total lateral pressure are used as indexes, and each index corresponds to 4 plan numbers. Each plan number corresponds to a maximum lateral pressure value strategy, and the 4 plan numbers correspond to four maximum lateral pressure value strategies. Each plan number includes the number of passes and the maximum lateral pressure of each pass.

[0060] In the embodiment of the present invention, the plan number values ​​corresponding to each steel grade are shown in the following table:

[0061] Table 1 The plan number value table corresponding to each steel grade

[0062]

[0063]

[0064] Among them, in Table 1, when the value of the total lateral pressure is a range value, the value of the total lateral pressure includes the lower boundary value but does not include the upper boundary value, that is, "47~57" means "47≤total lateral pressure<57".

[0065] In the embodiment of the present invention, the number of passes corresponding to each plan number and the maximum lateral pressure value of each pass are shown in the following table:

[0066] Table 2 The number of passes corresponding to each plan number and the maximum lateral pressure value of each pass

[0067]

[0068]

[0069] According to Table 1 and Table 2 set above, it can be seen that under the same number of passes, the maximum lateral pressure in the four plan numbers corresponding to each index gradually increases.

[0070] Further, in an embodiment of the present invention, based on the four maximum lateral pressure value taking strategies set above, when a maximum lateral pressure value taking strategy is selected from multiple preset maximum lateral pressure value taking strategies, calculation is first performed according to the first maximum lateral pressure value taking strategy; if the first maximum lateral pressure value taking strategy can meet the width requirement, the first maximum lateral pressure value taking strategy is selected; if the first maximum lateral pressure value taking strategy cannot meet the width requirement, calculation is performed according to the second maximum lateral pressure value taking strategy; if the second maximum lateral pressure value taking strategy can meet the width requirement, the second maximum lateral pressure value taking strategy is selected; if the second maximum lateral pressure value taking strategy cannot meet the width requirement, calculation is performed according to the third maximum lateral pressure value taking strategy; if the third maximum lateral pressure value taking strategy can meet the width requirement, the third maximum lateral pressure value taking strategy is selected; if the third maximum lateral pressure value taking strategy cannot meet the width requirement, the fourth maximum lateral pressure value taking strategy is selected.

[0071] In an embodiment of the present invention, based on the four maximum lateral pressure value taking strategies that are set, when each strip rolling is performed, the maximum lateral pressure value taking strategy is selected using the above-mentioned gradient calculation method, which can ensure that the selected maximum lateral pressure meets the rolling width control accuracy requirements, can greatly reduce the over-width and negative width ratio, and significantly improve the finished product yield.

[0072] Further, in an optional implementation of the embodiment of the present invention, when a maximum side pressure value strategy is selected from a plurality of preset maximum side pressure value strategies, the calculation result of the rough rolling last pass outlet width is determined according to the number of passes and the maximum side pressure in the first maximum side pressure value strategy, and when the calculated value of the rough rolling last pass outlet width minus the rough rolling last pass outlet width target value ≤ 3 mm, it is determined that the width requirement is met and the first maximum side pressure value strategy is selected; otherwise, it is determined that the width requirement is not met and the next step is executed;

[0073] According to the number of passes and the maximum side pressure in the second maximum side pressure value selection strategy, the calculation result of the rough rolling final pass outlet width is determined. When the calculated value of the rough rolling final pass outlet width minus the rough rolling final pass outlet width target value is ≤3mm, it is determined that the width requirement is met and the second maximum side pressure value selection strategy is selected. Otherwise, it is determined that the width requirement is not met and the next step is executed.

[0074] According to the number of passes and the maximum side pressure in the third maximum side pressure value selection strategy, the calculation result of the rough rolling last pass outlet width is determined. When the calculated value of the rough rolling last pass outlet width minus the rough rolling last pass outlet width target value is ≤3mm, it is determined that the width requirement is met and the third maximum side pressure value selection strategy is selected. Otherwise, it is determined that the width requirement is not met and the next step is executed.

[0075] The calculation result of the width of the last roughing pass outlet is determined according to the number of passes and the maximum side pressure in the fourth maximum side pressure value taking strategy. When the calculated value of the width of the last roughing pass outlet minus the target value of the width of the last roughing pass outlet is ≤3mm, it is determined that the width requirement is met and the fourth maximum side pressure value taking strategy is selected. Otherwise, it is determined that the width requirement is not met and the fourth maximum side pressure value taking strategy is still selected.

[0076] In an embodiment of the present invention, four corresponding plan numbers are determined according to the steel type, billet thickness, billet width, finished product thickness and total lateral pressure corresponding to the rolled strip steel, the first plan number corresponds to the first maximum lateral pressure value taking strategy, the second plan number corresponds to the second maximum lateral pressure value taking strategy, the third plan number corresponds to the third maximum lateral pressure value taking strategy, and the fourth plan number corresponds to the fourth maximum lateral pressure value taking strategy.

[0077] Furthermore, since the rough rolling usually only has a width gauge installed at the outlet of the odd pass, in the embodiment of the present invention, the side pressure of the subsequent pass is corrected and adjusted according to the actual rough rolling width measured after the previous pass is rolled, further comprising the following steps:

[0078] After each odd pass is rolled, the width of the current odd pass is measured using a width gauge at the rough rolling exit. The average width of the first 1 / 3 of the strip at the current odd pass exit is used as the current odd pass exit width. The current odd pass exit width is used as the width reference for calculating the lateral pressure, and the lateral pressure of subsequent passes is corrected and adjusted.

[0079] 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 combination with the 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.

[0080] Example 1

[0081] This embodiment rolls ordinary carbon steel, steel coil number: 948002503, steel type: Q195L; billet thickness 230mm, billet width 1275mm, finished product thickness 2.95mm, finished product width target 1225mm, user requirements according to 1230 ~ 1240mm supply.

[0082] Calculate the total side pressure = blank width - finished product width = 1275-1225 = 50 (mm).

[0083] The target value for finished product width control is 1235mm, and the target value for the final rough rolling exit width is calculated to be 1263mm.

[0084] According to Table 1, the plan numbers selected are 151, 152, 170, and 171.

[0085] The process of obtaining the number of passes and the lateral pressure is as follows:

[0086] 1) Select plan number 151. According to Table 2, the number of passes is 5. The maximum side pressure (mm) of the 1st, 3rd and 5th passes is 50, 81 and 30 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0087]

[0088] The calculation result of the rough rolling last pass outlet width is judged, the calculated value of the rough rolling last pass outlet width - the rough rolling last pass outlet width target value = 1274-1263 = 11 (mm) > 3mm, if the width requirement is not met, select the 152 plan number for recalculation;

[0089] 2) Select plan number 152. According to Table 2, the number of passes is 5. The maximum side pressure (mm) of the 1st, 3rd and 5th passes is 53, 87 and 35 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0090]

[0091] The calculation result of the rough rolling last pass outlet width is judged, the calculated value of the rough rolling last pass outlet width - the rough rolling last pass outlet width target value = 1269-1263 = 6 (mm) > 3mm, if the width requirement is not met, select the 170 plan number for recalculation;

[0092] 3) Select the 170 plan number. According to Table 2, the number of passes is 7. The maximum side pressure (mm) of the 1st, 3rd, 5th and 7th passes is 45, 75, 50 and 25 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0093]

[0094] The calculation result of the width of the last roughing pass outlet is judged, the calculated value of the width of the last roughing pass outlet - the target value of the width of the last roughing pass outlet = 1263-1263 = 0 (mm) < 3mm, which meets the width requirement, and the 170 plan number is selected as the maximum side pressure value strategy.

[0095] During the rolling process, after each odd pass is completed, when the first 1 / 3 of the strip at the pass exit is detected, the average width measurement of the first 1 / 3 of the strip is used as the width reference for calculating the side pressure, replacing the original width calculation value, and re-correcting the side pressure of the subsequent passes until the last pass. The specific control parameters during the rolling process are as follows:

[0096]

[0097]

[0098] Through continuous correction and calculation based on the measured values ​​during the rolling process, the rolling is stable. The measured value of the outlet width of the last pass of rough rolling is 1263mm, which is consistent with the target value of 1263mm. The measured value of the finished product width is 1234mm, which is 1mm different from the target value of 1235mm, meeting user requirements.

[0099] Example 2

[0100] This embodiment rolls low alloy structural steel, steel coil number: 948091403, steel type: HP295; billet thickness 230mm, billet width 1355mm, finished product thickness 3.5mm, finished product width target 1310mm, user requirements according to 1315 ~ 1325mm supply.

[0101] Calculate the total lateral pressure = blank width - finished product width = 1355-1310 = 45 (mm).

[0102] The target value for finished product width control is 1320mm, and the target value for the final rough rolling exit width is calculated to be 1354mm.

[0103] According to Table 1, the plan numbers selected are 350, 351, 352, and 370.

[0104] The process of obtaining the number of passes and the lateral pressure is as follows:

[0105] 1) Select the 350 plan number. According to Table 2, the number of passes is 5. The maximum side pressure (mm) of the 1st, 3rd and 5th passes is 47, 78 and 27 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0106]

[0107] The calculation result of the rough rolling last pass outlet width is judged. The calculated value of the rough rolling last pass outlet width - the rough rolling last pass outlet width target value = 1368-1354 = 14 (mm) > 3mm. If the width requirement is not met, select the 351 plan number for recalculation.

[0108] 2) Select the 351 plan number. According to Table 2, the number of passes is 5. The maximum side pressure (mm) of the 1st, 3rd and 5th passes is 52, 83 and 30 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0109]

[0110]

[0111] The calculation result of the rough rolling last pass outlet width is judged. The calculated value of the rough rolling last pass outlet width - the rough rolling last pass outlet width target value = 1363-1354 = 9 (mm) > 3mm. If the width requirement is not met, select the 352 plan number for recalculation.

[0112] 3) Select plan number 352. According to Table 2, the number of passes is 5. The maximum side pressure (mm) of the 1st, 3rd and 5th passes is 55, 90 and 35 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0113]

[0114] The calculation result of the width of the last roughing pass outlet is judged. The calculated value of the width of the last roughing pass outlet - the target value of the width of the last roughing pass outlet = 1355-1354 = 1 (mm) < 3mm. If the width requirement is met, plan number 352 is selected as the maximum side pressure value strategy.

[0115] During the rolling process, after each odd pass is completed, when the first 1 / 3 of the strip at the pass exit is detected, the average width measurement of the first 1 / 3 of the strip is used as the width reference for calculating the side pressure, replacing the original width calculation value, and re-correcting the side pressure of the subsequent passes until the last pass. The specific control parameters during the rolling process are as follows:

[0116]

[0117] Through continuous correction and calculation based on the measured values ​​during the rolling process, the rolling is stable. The measured value of the outlet width of the last pass of rough rolling is 1355mm, which is 1mm different from the target value of 1354mm. The measured value of the finished product width is 1322mm, which is 2mm different from the target value of 1320mm, meeting user requirements.

[0118] Example 3

[0119] This embodiment rolls high-strength steel, steel coil number: 948054806, steel type: TSJ-33; billet thickness 230mm, billet width 1130mm, finished product thickness 3.4mm, finished product width target 1070mm, user requirements according to 1075 ~ 1085mm supply.

[0120] Calculate the total lateral pressure = blank width - finished product width = 1130-1070 = 60 (mm).

[0121] The target value for finished product width control is 1080mm, and the target value for the final rough rolling exit width is calculated to be 1105mm.

[0122] According to Table 1, the plan numbers selected are 452, 470, 471, and 472.

[0123] The process of obtaining the number of passes and the lateral pressure is as follows:

[0124] 1) Select the 452 plan number. According to Table 2, the number of passes is 5. The maximum side pressure (mm) of the 1st, 3rd and 5th passes is 60, 90 and 35 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0125]

[0126] The calculation result of the rough rolling last pass outlet width is judged. The calculated value of the rough rolling last pass outlet width - the rough rolling last pass outlet width target value = 1121-1105 = 16 (mm) > 3mm. If the width requirement is not met, select the 470 plan number for recalculation.

[0127] 2) Select the 470 plan number. According to Table 2, the number of passes is 7. The maximum side pressure (mm) of the 1st, 3rd, 5th and 7th passes is 53, 85, 52 and 30 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0128]

[0129] The calculation result of the rough rolling last pass outlet width is judged, the calculated value of the rough rolling last pass outlet width - the rough rolling last pass outlet width target value = 1117-1105 = 12 (mm) > 3mm, if the width requirement is not met, select the 471 plan number for recalculation;

[0130] 3) Select plan number 471. According to Table 2, the number of passes is 7. The maximum side pressure (mm) of the 1st, 3rd, 5th and 7th passes is 55, 87, 57 and 32 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0131]

[0132]

[0133] The calculation result of the rough rolling last pass outlet width is judged. The calculated value of the rough rolling last pass outlet width - the rough rolling last pass outlet width target value = 1110-1105 = 5 (mm) > 3mm. If the width requirement is not met, select the 472 plan number for recalculation.

[0134] 4) Select plan number 472. According to Table 2, the number of passes is 7. The maximum side pressure (mm) of the 1st, 3rd, 5th and 7th passes is 60, 90, 61 and 35 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0135]

[0136] The calculation result of the width of the last roughing pass outlet is judged. The calculated value of the width of the last roughing pass outlet - the target value of the width of the last roughing pass outlet = 1105-1105 = 0 (mm) < 3mm. If the width requirement is met, plan number 472 is selected as the maximum side pressure value strategy.

[0137] During the rolling process, after each odd pass is completed, when the first 1 / 3 of the strip at the pass exit is detected, the average width measurement of the first 1 / 3 of the strip is used as the width reference for calculating the side pressure, replacing the original width calculation value, and re-correcting the side pressure of the subsequent passes until the last pass. The specific control parameters during the rolling process are as follows:

[0138]

[0139] Through continuous correction and calculation based on the measured values ​​during the rolling process, the rolling is stable. The measured value of the outlet width of the last pass of rough rolling is 1104mm, which is 1mm different from the target value of 1105mm. The measured value of the finished product width is 1080mm, which is consistent with the target value of 1080mm, meeting user requirements.

[0140] Example 4

[0141] This embodiment rolls low-grade silicon steel, steel coil number: 948524403, steel type: DW130; billet thickness 222mm, billet width 1250mm, finished product thickness 2.6mm, finished product width target 1227mm, user requirements according to 1237 ~ 1247mm supply.

[0142] The target thickness of rough rolling is 47mm.

[0143] Calculate the total lateral pressure = blank width - finished product width = 1250-1227 = 23 (mm).

[0144] The target value for finished product width control is 1242mm, and the target value for the final rough rolling exit width is calculated to be 1271mm.

[0145] According to Table 1, the plan numbers selected are 550, 551, 552, and 570.

[0146] The process of obtaining the number of passes and the lateral pressure is as follows:

[0147] 1) Select the 550 plan number. According to Table 2, the number of passes is 5. The maximum side pressure (mm) of the 1st, 3rd and 5th passes is 5, 30 and 18 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0148]

[0149] The calculation result of the rough rolling last pass outlet width is judged, the calculated value of the rough rolling last pass outlet width - the rough rolling last pass outlet width target value = 1275-1271 = 4 (mm) > 3mm, if the width requirement is not met, select the 551 plan number for recalculation;

[0150] 2) Select the plan number 551. According to Table 2, the number of passes is 5. The maximum side pressure (mm) of the 1st, 3rd and 5th passes is 5, 40 and 20 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0151]

[0152] The calculation result of the width of the last roughing pass outlet is judged. The calculated value of the width of the last roughing pass outlet - the target value of the width of the last roughing pass outlet = 1271-1271 = 0 (mm) < 3mm. If the width requirement is met, plan number 551 is selected as the maximum side pressure value strategy.

[0153] During the rolling process, after each odd pass is completed, when the first 1 / 3 of the strip at the pass exit is detected, the average width measurement of the first 1 / 3 of the strip is used as the width reference for calculating the side pressure, replacing the original width calculation value, and re-correcting the side pressure of the subsequent passes until the last pass. The specific control parameters during the rolling process are as follows:

[0154]

[0155] Through continuous correction and calculation based on the measured values ​​during the rolling process, the rolling is stable. The measured value of the outlet width of the last pass of rough rolling is 1272mm, which is 1mm different from the target value of 1271mm. The measured value of the finished product width is 1242mm, which is equal to the target value of 1242mm, meeting user requirements.

[0156] Example 5

[0157] This embodiment rolls high-grade silicon steel, steel coil number: 948428816, steel type: DV19A; billet thickness 222mm, billet width 1300mm, finished product thickness 2.3mm, finished product width target 1285mm, user requirements according to 1295 ~ 1305mm supply.

[0158] The target thickness of rough rolling is 40mm.

[0159] Calculate the total lateral pressure = blank width - finished product width = 1300-1285 = 15 (mm).

[0160] The target value for finished product width control is 1300mm, and the target value for the final rough rolling exit width is calculated to be 1324mm.

[0161] According to Table 1, the plan numbers selected are 651, 652, 653, and 670.

[0162] The process of obtaining the number of passes and the lateral pressure is as follows:

[0163] 1) Select the plan number 651. According to Table 2, the number of passes is 5. The maximum side pressure (mm) of the 1st, 3rd and 5th passes is 7, 45 and 20 respectively. The rough rolling width is calculated. The calculation results are as follows:

[0164]

[0165] The calculation result of the width of the last roughing pass outlet is judged. The calculated value of the width of the last roughing pass outlet - the target value of the width of the last roughing pass outlet = 1324-1324 = 0 (mm) < 3mm. If the width requirement is met, plan number 651 is selected as the maximum side pressure value strategy.

[0166] During the rolling process, after each odd pass is completed, when the first 1 / 3 of the strip at the pass exit is detected, the average width measurement of the first 1 / 3 of the strip is used as the width reference for calculating the side pressure, replacing the original width calculation value, and re-correcting the side pressure of the subsequent passes until the last pass. The specific control parameters during the rolling process are as follows:

[0167]

[0168] Through continuous correction and calculation based on the measured values ​​during the rolling process, the rolling is stable. The measured value of the outlet width of the last pass of rough rolling is 1324mm, which is equal to the target value of 1324mm. The measured value of the finished product width is 1302mm, which is 2mm different from the target value of 1300mm, meeting user requirements.

[0169] It can be seen that the rolling width control method based on the continuous optimization of the side pressure strategy provided by the embodiment of the present invention can improve the rolling width control accuracy, greatly reduce the over-width and negative width ratio, and significantly improve the finished product yield.

[0170] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including 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 article are all referenced to the placement state shown in the accompanying drawings.

[0171] 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 embodiments of the present invention.

Claims

1. A rolling width control method based on continuous optimization of side pressure strategy, characterized in that: include: With steel type, billet thickness, billet width, finished product thickness and total side pressure as indexes, multiple maximum side pressure value strategies are preset for each type of steel type; Before rough rolling, according to the steel type, actual side pressure requirement and rough rolling width requirement, a maximum side pressure value strategy is selected from multiple preset maximum side pressure value strategies, and the number of rolling passes and the side pressure amount of each pass are determined according to the selected maximum side pressure value strategy; During the rough rolling process, based on the selected number of rolling passes and the side pressure of each pass, the side pressure of the subsequent pass is corrected and adjusted according to the actual rough rolling width measured after the previous pass.

2. The rolling width control method based on continuous optimization of side pressure strategy according to claim 1 is characterized in that: There are 4 preset maximum lateral pressure value strategies for each type of steel.

3. The rolling width control method based on continuous optimization of side pressure strategy according to claim 2 is characterized in that: With steel type, billet thickness, billet width, finished product thickness and total lateral pressure as indexes, each index corresponds to 4 plan numbers, each plan number corresponds to a maximum lateral pressure value strategy, and the 4 plan numbers correspond to four maximum lateral pressure value strategies. Each plan number includes the number of passes and the maximum lateral pressure of each pass.

4. The rolling width control method based on continuous optimization of side pressure strategy according to claim 3 is characterized in that: The plan number values ​​corresponding to each steel grade are set as: The number of passes corresponding to each plan number and the maximum lateral pressure value of each pass are set as follows: When the value of the total lateral pressure is a range value, the value of the total lateral pressure includes the lower boundary value but does not include the upper boundary value.

5. The rolling width control method based on continuous optimization of side pressure strategy according to claim 4 is characterized in that: When selecting a maximum lateral pressure value strategy from multiple preset maximum lateral pressure value strategies, first calculate according to the first maximum lateral pressure value strategy. If the first maximum lateral pressure value strategy can meet the width requirement, the first maximum lateral pressure value strategy is selected. If the first maximum lateral pressure value strategy cannot meet the width requirement, the second maximum lateral pressure value strategy is used for calculation; If the second maximum lateral pressure value selection strategy can meet the width requirement, the second maximum lateral pressure value selection strategy is selected; if the second maximum lateral pressure value selection strategy cannot meet the width requirement, the third maximum lateral pressure value selection strategy is used for calculation; If the third maximum lateral pressure value taking strategy can meet the width requirement, then the third maximum lateral pressure value taking strategy is selected; if the third maximum lateral pressure value taking strategy cannot meet the width requirement, then the fourth maximum lateral pressure value taking strategy is selected.

6. The rolling width control method based on continuous optimization of side pressure strategy according to claim 4 is characterized in that: When selecting a maximum side pressure value strategy from multiple preset maximum side pressure value strategies, the calculation result of the rough rolling last pass outlet width is determined according to the number of passes and the maximum side pressure in the first maximum side pressure value strategy. When the calculated value of the rough rolling last pass outlet width minus the rough rolling last pass outlet width target value is ≤3mm, it is determined that the width requirement is met and the first maximum side pressure value strategy is selected. Otherwise, it is determined that the width requirement is not met and the next step is executed. According to the number of passes and the maximum side pressure in the second maximum side pressure value selection strategy, the calculation result of the rough rolling final pass outlet width is determined. When the calculated value of the rough rolling final pass outlet width minus the rough rolling final pass outlet width target value is ≤3mm, it is determined that the width requirement is met and the second maximum side pressure value selection strategy is selected. Otherwise, it is determined that the width requirement is not met and the next step is executed. According to the number of passes and the maximum side pressure in the third maximum side pressure value selection strategy, the calculation result of the rough rolling last pass outlet width is determined. When the calculated value of the rough rolling last pass outlet width minus the rough rolling last pass outlet width target value is ≤3mm, it is determined that the width requirement is met and the third maximum side pressure value selection strategy is selected. Otherwise, it is determined that the width requirement is not met and the next step is executed. The calculation result of the width of the last roughing pass outlet is determined according to the number of passes and the maximum side pressure in the fourth maximum side pressure value taking strategy. When the calculated value of the width of the last roughing pass outlet minus the target value of the width of the last roughing pass outlet is ≤3mm, it is determined that the width requirement is met and the fourth maximum side pressure value taking strategy is selected. Otherwise, it is determined that the width requirement is not met and the fourth maximum side pressure value taking strategy is still selected.

7. The rolling width control method based on continuous optimization of side pressure strategy according to claim 1 is characterized in that: The side pressure of the subsequent pass is corrected and adjusted according to the actual rough rolling width measured after the previous pass, including: After each odd pass is rolled, the width of the current odd pass is measured using a width gauge at the rough rolling exit. The average width of the first 1 / 3 of the strip at the current odd pass exit is used as the current odd pass exit width. The current odd pass exit width is used as the width reference for calculating the lateral pressure, and the lateral pressure of subsequent passes is corrected and adjusted.

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