Hot strip rolling coiling temperature control method

Abstract

The present application relates to a kind of hot strip coiling temperature control method, belong to hot strip rolling technical field.The control method is based on the existing strip coiling before forecast temperature T pre, introduce the control temperature T control of strip coiling before with T pre same cycle and the compensation temperature T compensation of strip in laminar cooling section, further introduce the unit length temperature k of compensation temperature T compensation and fine tuning temperature t and in the each cycle of sampling constantly calculate and reassign, so that T compensation and T control The calculated value can be constantly updated with cycle and more accurate;Finally, by comparing the absolute value of the difference between T pre and T control of each cycle with the set limit deviation value and comparing T pre and T control, adjust the laminar cooling water injection amount set in the previous cycle and as the laminar cooling water injection amount newly set in the current cycle, make the laminar cooling water injection amount set in each cycle more accurate, so that the actual coiling temperature of strip can be more accurately controlled.

Description

TECHNICAL FIELD

[0001] The present application relates to a hot continuous rolling strip coiling temperature control method, belonging to the technical field of hot continuous rolling. BACKGROUND

[0002] At present, on the 1422mm hot continuous rolling production line of Shanghai Meishan Iron and Steel Co., Ltd., after the strip is rolled out from the finishing mill, the strip is cooled by the laminar cooling section and reaches the coiler, the strip has a temperature requirement when coiling, generally designed with a coiling target temperature, such as Figure 1 The finishing mill and coiling equipment distribution map, the finishing mill outlet and the coiling inlet are respectively provided with pyrometers (symbol P), and the laminar cooling equipment is arranged between the pyrometers. In order to make the strip reach the coiling target temperature when coiling, the production line is provided with a laminar cooling control model (abbreviated as CTC model) which specially controls the laminar cooling of the whole length of the strip. At present, the method for controlling the coiling temperature of the strip by using the model is: the measured finishing mill outlet temperature, thickness, width, speed, coiling inlet temperature and set laminar cooling water spraying amount are sampled according to the specified period, and the coiling front predicted temperature T 预 is calculated and predicted once according to the sampling data in each period to form a periodic prediction. By comparing the coiling front predicted temperature T 预 with the set strip coiling target temperature T 目 , the reduction and increase of the laminar cooling water spraying amount are respectively adjusted, so that the temperature of the strip when coiling is close to the set strip coiling target temperature T 目 .

[0003] However, when the strip runs through the laminar cooling section, the temperature drop is affected by many factors, and only by comparing the coiling front predicted temperature T 预 calculated by the above-mentioned data sampled periodically with the strip coiling target temperature T 目 cannot more accurately control the actual coiling temperature of the strip to reach the set strip coiling target temperature T 目 . The coiling temperature control precision of the 1422mm hot continuous rolling production line is still insufficient. SUMMARY

[0004] The technical problem to be solved by the present application is: how to more accurately adjust the laminar cooling water spraying amount of the existing Meishan 1422mm hot continuous rolling production line, so that the actual coiling temperature of the strip is closer to the coiling target temperature, and the full-length coiling temperature control precision of the strip is improved.

[0005] The technical solution provided by the present application to solve the above technical problem is: a hot continuous rolling strip coiling temperature control method,

[0006] The present application relates to a process of hot continuous rolling of a strip steel from a full length to coiling, and using a laminar cooling control model of the production line, an initial water spraying amount of the laminar cooling is set, and a measured sampling and calculation period unit is set, a period number n = full length of the strip steel / period unit is calculated by measuring the full length of the strip steel and sampling and calculating each period, and the finishing mill exit temperature, thickness, width, speed, coiling inlet temperature T 实 and water spraying amount of the laminar cooling of each period are calculated and predicted, and the strip steel coiling predicted temperature T 预 of each period is calculated and predicted; characterized in that the following steps are performed at the same time as the calculation and prediction of the T 预 .

[0007] 1) the strip steel coiling control temperature T 预 of the same period as the T 控 is calculated according to the following formula (1);

[0008] T 控 =T 目 +T 补 (1),

[0009] In formula (1), T 目 is the set strip steel coiling target temperature, T 补 is the compensation temperature of the strip steel in the laminar cooling section at the same period as the T 预 ; and T 补 is calculated according to the following formula (2):

[0010] T 补 =k*X+t, (2),

[0011] In formula (2), X is the length of the strip steel running cumulatively, k is the unit length temperature of the strip steel running, and t is the fine adjustment temperature of the strip steel running;

[0012] A. When the strip steel starts running and is not sampled, X = 0, t = 0, the initial temperature compensation T 补 = 0, and T 控 = T 目 .

[0013] B. After the strip steel running starts and is sampled in a period, the unit length temperature k and the fine adjustment temperature t in each period are calculated according to the unit length temperature value and the fine adjustment temperature value of the previous period according to the following formulas (3) and (4), and the unit length temperature value and the fine adjustment temperature value of the previous period are re-assigned, the initial unit length temperature k and the fine adjustment temperature t are both set to zero,

[0014] k = k 前 + (k 实 -k 预 )*g (3),

[0015] t = t 前 + (t 实 - t 预 )*g (4),

[0016] wherein k 实 and t 实 are the unit length temperature and the fine adjustment temperature of the current period calculated according to the measured coiling inlet temperature of the strip, k 预 and t 预 are the unit length and fine adjustment temperature calculated according to the predicted temperature before coiling, k 前 and t 前 are the unit length temperature and the fine adjustment temperature calculated in the previous period, and g is a fixed coefficient, k 实 , t 实 , k 预 and t 预 are calculated according to the following formulas (5), (6), (7) and (8);

[0017] k 实 = ((n*∑(X*T 实 )) - (∑X*∑T 实 )) / ((n*∑(X*X)) - (∑X*∑X)) (5),

[0018] t 实 = (T 实 - (k 实 *X)) / n (6),

[0019] k 预 = ((n*∑(X*T 预 )) - (∑X*∑T 预 )) / ((n*∑(X*X)) - (∑X*∑X)) (7),

[0020] t 预 = (T 预 - (k 预 *X)) / n (8) ;

[0021] 2) The absolute value Δt of the difference between the predicted temperature T 预 of the strip before coiling calculated in the same period and the controlled temperature T 控 of the strip before coiling is compared with the set limit deviation value and controlled as follows:

[0022] A. When Δt is less than the limit deviation value, the laminar cooling water spraying amount of the previous period is kept unchanged;

[0023] B. When Δt is greater than the limit deviation value,

[0024] if T 预 is greater than T控 , increase the laminar cooling water spray amount of the previous cycle until Δt is less than the limit deviation value, and the increased laminar cooling water spray amount is set as the new laminar cooling water spray amount of the current cycle,

[0025] If T 预 is less than T 控 , decrease the laminar cooling water spray amount of the previous cycle until Δt is less than the limit deviation value, and the decreased laminar cooling water spray amount is set as the new laminar cooling water spray amount of the current cycle;

[0026] 3) In each cycle, repeat steps 1) and 2) until the end after completing all cycle numbers of the full length of the strip for actual sampling and calculation.

[0027] The beneficial effects of the present application are: on the basis of the strip coiling predicted temperature T 预 given by the existing 1422mm hot continuous rolling production line laminar cooling control model (CTC model), the present application further introduces the strip coiling control temperature T 预 of the same cycle as the strip coiling predicted temperature T 控 , the compensation temperature T 补 of the strip in the laminar cooling section, and further introduces the unit length temperature k and fine tuning temperature t for calculating the compensation temperature T 补 , and after the start cycle sampling, the unit length temperature k and fine tuning temperature t calculated for each cycle are constantly recalculated and assigned, i.e. the unit length temperature k and fine tuning temperature t calculated in the current cycle cover the unit length temperature k and fine tuning temperature t calculated in the previous cycle, so that the compensation temperature T 补 of the strip running in the laminar cooling section and the calculation value of the coiling control temperature T 控 can be constantly updated to obtain more accurate T 控 calculation value; finally, by comparing the absolute value of the difference between the strip coiling predicted temperature T 预 and T 控 in each cycle (the same cycle) with the set limit deviation value and comparing T 预 and T 控 , the laminar cooling water spray amount set in the previous cycle is adjusted, and the adjusted laminar cooling water spray amount is set as the new laminar cooling water spray amount, so that the adjustment and re-setting of the laminar cooling water spray amount in each sampling cycle is more accurate, so that the actual coiling temperature of the strip can be more accurately controlled.

[0028] The further improvement of the above technical solution is: according to the running speed of the strip, it is divided into four speeds of uniform speed, speed-up, high speed and deceleration, and the strip running in the laminar cooling section is divided into five running sections of uniform speed head section, uniform speed section, speed-up section, high speed section and deceleration section, accordingly:

[0029] the predicted temperature T of the strip before coiling 预 into five kinds, respectively, are the predicted temperature T of the strip before coiling calculated when the strip runs in the uniform head section 头预 , the predicted temperature T of the strip before coiling calculated when the strip runs in the uniform section except the uniform head section 匀预 , the predicted temperature T of the strip before coiling calculated when the strip runs in the acceleration section 升预 , the predicted temperature T of the strip before coiling calculated when the strip runs in the high speed section 高预 , and the predicted temperature T of the strip before coiling calculated when the strip runs in the deceleration section 减预 ;

[0030] the T 补 into five kinds of compensation temperatures, respectively, are the head compensation temperature T calculated when the strip runs in the uniform head section 0补 , the uniform compensation temperature T calculated when the strip runs in the uniform section except the uniform head section 1补 , the compensation temperature T calculated when the strip runs in the acceleration section 2补 , the compensation temperature T calculated when the strip runs in the high speed section 3补 , and the compensation temperature T calculated when the strip runs in the deceleration section 4补 ;

[0031] the unit length temperature k and the fine adjustment temperature t are divided into five kinds, respectively, are: the head unit length temperature k0 and the head fine adjustment temperature t0 calculated when the strip runs in the uniform head section, the uniform section unit length temperature k1 and the uniform section fine adjustment temperature t1 calculated when the strip runs in the uniform section except the uniform head section, the unit length temperature k2 and the fine adjustment temperature t2 calculated when the strip runs in the acceleration section, the unit length temperature k3 and the fine adjustment temperature t3 calculated when the strip runs in the high speed section, and the unit length temperature k4 and the fine adjustment temperature t4 calculated when the strip runs in the deceleration section;

[0032] in the first step, the T 0补 , the T 1补 , the T 2补 , the T 3补 , and the T 4补 are calculated according to the following formulas (9), (10), (11), (12) and (13), respectively,

[0033] when X≤S0<S1, T 0补 =t0; (9),

[0034] when X≤S1, T 1补 =X*k1+t1; (10),

[0035] when X≤S1+S2, T 2补=S1*k1+(X-S1)*k2+t2; (11),

[0036] When X≤S1+S2+S3, T 3补 =S1*k1+S2*k2+(X-S1-S2)*k3+t3; (12),

[0037] When X≤S1+S2+S3+S4, T 4补 =S1*k1+S2*k2+S3*k3+(X-S1-S2-S3)*k4+t4; (13),

[0038] In equations (9)-(13), S1 is the running length of the strip when it runs at a constant speed, S0 is the running length of the strip when it runs at the head of a constant speed section (i.e., a section at the head of S1), S2 is the running length of the strip when it runs at an increasing speed, S3 is the running length of the strip when it runs at a high speed, and S4 is the running length of the strip when it runs at a decreasing speed.

[0039] The terms k0, k1, k2, k3, k4 and t0, t1, t2, t3, t4 are expanded according to equations (3) and (4) above as follows: (14)-(23)

[0040] k0=k 0前 +(k 0实 -k 0预 )*g (14),

[0041] k1=k 1前 +(k 1实 -k 1预 )*g (15),

[0042] k2=k 2前 +(k 2实 -k 2预 )*g (16),

[0043] k3=k 3前 +(k 3实 -k 3预 )*g (17),

[0044] k4 = k 4前 +(k 4实 -k 4预 )*g (18),

[0045] t0 = t 0前 +(t 0实 -t 0预 )*g (19),

[0046] t1=t 1前 +(t 1实 -t1预 )*g (20),

[0047] t2 = t 2前 +(t 2实 -t 2预 )*g (21),

[0048] t3 = t 3前 +(t 3实 -t 3预 )*g (22),

[0049] t4 = t 4前 +(t 4实 -t 4预 )*g (23),

[0050] In the formulae (14) - (23), k 0实 and t 0实 are the unit length temperature and the fine tuning temperature of the current period when the strip is running in the uniform speed head section, calculated according to the measured strip coiling inlet temperature, k 0预 and t 0预 are the unit length and the fine tuning temperature of the current period when the strip is running in the uniform speed head section, calculated according to the pre-coiling forecast temperature; k 1实 and t 1实 are the unit length temperature and the fine tuning temperature of the current period when the strip is running in the uniform speed section other than the uniform speed head section, calculated according to the measured strip coiling inlet temperature, k 1预 and t 1预 are the unit length and the fine tuning temperature of the current period when the strip is running in the uniform speed section other than the uniform speed head section, calculated according to the pre-coiling forecast temperature; k 2实 and t 2实 are the unit length temperature and the fine tuning temperature of the current period when the strip is running in the speed-up section, calculated according to the measured strip coiling inlet temperature, k 2预 and t 2预 are the unit length and the fine tuning temperature of the current period when the strip is running in the speed-up section, calculated according to the pre-coiling forecast temperature; k 3实 and t 3实 are the unit length temperature and the fine tuning temperature of the current period when the strip is running in the high speed section, calculated according to the measured strip coiling inlet temperature, k 3预 and t 3预 are the unit length and the fine tuning temperature of the current period when the strip is running in the high speed section, calculated according to the pre-coiling forecast temperature; k 4实 and t 4实 are the unit length temperature and the fine tuning temperature of the current period when the strip is running in the speed-down section, calculated according to the measured strip coiling inlet temperature, k 4预 and t 4预are the unit length and fine temperature of the current cycle calculated according to the predicted temperature before coiling when the strip runs in the deceleration section, respectively; 0前 and t 0前 are the unit length and fine temperature of the previous cycle calculated when the strip runs in the uniform speed head section, respectively; 1前 and t 1前 are the unit length and fine temperature of the previous cycle calculated when the strip runs in the uniform speed section except the uniform speed head section, respectively; 2前 and t 2前 are the unit length and fine temperature of the previous cycle calculated when the strip runs in the acceleration section, respectively; 3前 and t 3前 are the unit length and fine temperature of the previous cycle calculated when the strip runs in the high speed section, respectively; 4前 and t 4前 are the unit length and fine temperature of the previous cycle calculated when the strip runs in the deceleration section, respectively;

[0051] The k 0实 , k 1实 , k 2实 , k 3实 , k 4实 , t 0实 , t 1实 , t 2实 , t 3实 , t 4实 and k 0预 , k 1预 , k 2预 , k 3预 , k 4预 , t 0预 , t 1预 , t 2预 , t 3预 , t 4预 are respectively expanded as follows (24)-(43) according to the above formulae (5)-(8):

[0052] k 0实 = ((n*∑(X*T 0实 ))-(∑X*∑T 0实 )) / ((n*∑(X*X))-(∑X*∑X)) (24),

[0053] k 1实 = ((n*∑(X*T 1实 ))-(∑X*∑T 1实 )) / ((n*∑(X*X))-(∑X*∑X)) (25),

[0054] k 2实 = ((n*∑(X*T 2实)) - (∑X * ∑T 2实 )) / ((n * ∑(X * X)) - (∑X * ∑X)) (26),

[0055] k 3实 = ((n * ∑(X * T 3实 )) - (∑X * ∑T 3实 )) / ((n * ∑(X * X)) - (∑X * ∑X)) (27),

[0056] k 4实 = ((n * ∑(X * T 4实 )) - (∑X * ∑T 4实 )) / ((n * ∑(X * X)) - (∑X * ∑X)) (28),

[0057] t 0实 = (T 0实 - (k 0实 * X)) / n (29),

[0058] t 1实 = (T 1实 - (k 1实 * X)) / n (30),

[0059] t 2实 = (T 2实 - (k 2实 * X)) / n (31),

[0060] t 3实 = (T 3实 - (k 3实 * X)) / n (32),

[0061] t 4实 = (T 4实 - (k 4实 * X)) / n (33),

[0062] k 0预 = ((n * ∑(X * T 0预 )) - (∑X * ∑T 0预 )) / ((n * ∑(X * X)) - (∑X * ∑X)) (34),

[0063] k 1预 = ((n * ∑(X * T 1预 )) - (∑X * ∑T 1预 )) / ((n * ∑(X * X)) - (∑X * ∑X)) (35),

[0064] k 2预 = ((n * ∑(X * T 2预 )) - (∑X * ∑T2预 )) / ((n*∑(X*X))-(∑X*∑X)) (36),

[0065] k 3预 =((n*∑(X*T 3预 ))-(∑X*∑T 3预 )) / ((n*∑(X*X))-(∑X*∑X)) (37),

[0066] k 4预 =((n*∑(X*T 4预 ))-(∑X*∑T 4预 )) / ((n*∑(X*X))-(∑X*∑X)) (38),

[0067] t 0预 =(T 0预 -(k 0预 *X)) / n (39),

[0068] t 1预 =(T 1预 -(k 1预 *X)) / n (40),

[0069] t 2预 =(T 2预 -(k 2预 *X)) / n (41),

[0070] t 3预 =(T 3预 -(k 3预 *X)) / n (42),

[0071] t 4预 =(T 4预 -(k 4预 *X)) / n (43),

[0072] In the above equations (24)-(43), T 0实 is the measured strip coiling entry temperature when the strip is running in the uniform head section, T 0预 is the calculated pre-coiling forecast temperature when the strip is running in the uniform head section; T 1实 is the measured strip coiling entry temperature when the strip is running in the uniform section other than the uniform head section, T 1预 is the calculated pre-coiling forecast temperature when the strip is running in the uniform section other than the uniform head section; T 2实 is the measured strip coiling entry temperature when the strip is running in the accelerating section, T 2预 is the calculated pre-coiling forecast temperature when the strip is running in the accelerating section; T 3实 is the measured strip coiling entry temperature when the strip is running in the high speed section, T3预 is the calculated pre-coiling forecast temperature of the strip steel when the strip steel runs in the high-speed section; T 4实 is the measured pre-coiling entry temperature of the strip steel when the strip steel runs in the deceleration section, T 4预 is the calculated pre-coiling forecast temperature of the strip steel when the strip steel runs in the deceleration section;

[0073] According to the T 0补 , T 1补 , T 2补 , T 3补 and T 4补 , five kinds of pre-coiling control temperatures of the strip steel are respectively obtained according to (1): the calculated pre-coiling control temperature of the strip steel when the strip steel runs in the uniform-speed head section T 0控 , the calculated pre-coiling control temperature of the strip steel when the strip steel runs in the uniform-speed section except the uniform-speed head section T 1控 , the calculated pre-coiling control temperature of the strip steel when the strip steel runs in the acceleration section T 2控 , the calculated pre-coiling control temperature of the strip steel when the strip steel runs in the high-speed section T 3控 and the calculated pre-coiling control temperature of the strip steel when the strip steel runs in the deceleration section T 4控 , the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 are as follows (44)-(48):

[0074] T 0控 = T 目 + T 0补 (44),

[0075] T 1控 = T 目 + T 1补 (45),

[0076] T 2控 = T 目 + T 2补 (46),

[0077] T 3控 = T 目 + T 3补 (47),

[0078] T 4控 = T 目 + T 4补 (48),

[0079] In the second step, the absolute values Δt are five respectively: the absolute value Δt0 calculated when the strip runs in the uniform speed head section, the absolute value Δt1 calculated when the strip runs in the uniform speed section except the uniform speed head section, the absolute value Δt2 calculated when the strip runs in the speed-up section, the absolute value Δt3 calculated when the strip runs in the high speed section, and the absolute value Δt4 calculated when the strip runs in the speed-down section, which are calculated according to the following formulas (49)-(53) respectively:

[0080] Δt0 = |T 0预 -T 0控 (49),

[0081] Δt1 = |T 1预 -T 1控 (50),

[0082] Δt2 = |T 2预 -T 2控 (51),

[0083] Δt3 = |T 3预 -T 3控 (52),

[0084] Δt4 = |T 4预 -T 4控 (53),

[0085] According to the current period occurring in one of the five running sections, the corresponding Tact is obtained by the actual measurement, and the corresponding T 预 , k 实 , t 实 , k 预 , t 预 , k, t, T 补 and T 控 are calculated when the strip runs in one of the five running sections in the current period.

[0086] The further improvements to this invention provide additional beneficial effects: The laminar cooling section is further divided into five operating segments based on the four speed variations of the strip, thereby refining the measured strip coiling inlet temperature Tactual when the strip falls into one of the five operating segments in each sampling period, and correspondingly calculating the predicted strip coiling temperature Tpredicted and the compensation temperature Tcomplemented of the strip in the laminar cooling section. Simultaneously, the unit length temperature k and fine-tuning temperature t calculated when the strip falls into one of the five operating segments in each sampling period are further refined and continuously reassigned (the calculated value of the current period overwrites the calculated value of the previous period), making the unit length temperature k and fine-tuning temperature t closer to the actual temperature drop of the strip in the laminar cooling section due to speed variations, thus further improving the accuracy of the actual strip coiling temperature.

[0087] A further improvement to the above technical solution is: based on the current cycle occurring when the strip is running in one of the five operating segments, the coiling inlet temperature T of the strip when it is running in one of the five operating segments in the current cycle is obtained by actual measurement. 0实 T 1实 T 2实 T 3实 and T 4实 One of them; and accordingly calculate the following data when the strip steel is operating in one of the five operating segments in the current cycle:

[0088] The T 0预 T 1预 T 2预 T 3预 and T 4预 one,

[0089] The k 0实 k 1实 k 2实 k 3实 and k 4实 one,

[0090] The t 0实 t 1实 t 2实 t 3实 and t 4实 one,

[0091] The k 0预 k 1预 k 2预 k 3预 and k 4预 one,

[0092] The t 0预 t 1预 t 2预 t 3预 and t 4预one of the k0, k1, k2, k3 and k4,

[0093] one of the k0, k1, k2, k3 and k4,

[0094] one of the t0, t1, t2, t3 and t4,

[0095] one of the T 0补 , T 1补 , T 2补 , T 3补 and T 4补 ,

[0096] one of the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 ;

[0097] in the second step, one of the absolute values Δt0, Δt1, Δt2, Δt3 and Δt4 of the difference between one of the T 0预 , T 1预 , T 2预 , T 3预 and T 4预 and one of the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 calculated in the same period is calculated, and then one of the Δt0, Δt1, Δt2, Δt3 and Δt4 is compared with a set limit deviation value and controlled as follows:

[0098] A. when one of the Δt0, Δt1, Δt2, Δt3 and Δt4 is less than the limit deviation value, the laminar cooling water spray amount of the previous period is kept unchanged;

[0099] B. when one of the Δt0, Δt1, Δt2, Δt3 and Δt4 is greater than the limit deviation value,

[0100] if one of the T 0预 , T 1预 , T 2预 , T 3预 and T 4预 is greater than one of the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 respectively, the laminar cooling water spray amount of the previous period is increased until Δt is less than the limit deviation value, and the increased laminar cooling water spray amount is taken as the newly set laminar cooling water spray amount of the current period;

[0101] If one of the T 0预 , T 1预 , T 2预 , T 3预 and T 4预 is less than one of the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 respectively, reduce the laminar cooling water spraying amount of the previous cycle until Δt is less than the limit deviation value, and take the reduced laminar cooling water spraying amount as the newly set laminar cooling water spraying amount of the current cycle.

[0102] The improvement of the above technical solution is that the setting period is 5 meters per piece, the fixed coefficient g is 0.3, and the limit deviation value is 1. BRIEF DESCRIPTION OF DRAWINGS

[0103] The hot continuous rolling strip coiling temperature control method of the present application will be further described below in combination with the drawings.

[0104] Figure 1 is a planar layout diagram of the finishing and coiling equipment of the hot continuous rolling production line involved in the first embodiment of the present application.

[0105] Figure 2 is a segmented coiling temperature control diagram in the laminar cooling section using the hot continuous rolling strip coiling temperature control method of the second embodiment of the present application. DETAILED DESCRIPTION

[0106] Embodiment One

[0107] The hot continuous rolling strip coiling temperature control method of the present embodiment is related to the process of rolling a strip to coiling in the existing 1422mm hot continuous rolling production line, and utilizes the existing laminar cooling control model (CTC model for short) of the production line, as shown in Figure 1 The hot continuous rolling production line has 7 groups of finishing mills, and the length of the laminar cooling section from the outlet of the finishing mill to the coiler is 131286mm (131.286 meters). In the present embodiment, for the AP1360C2 steel grade of 2.75*1045 produced, the coiling target temperature is set to 570℃, and the rolling length of the strip is 780 meters.

[0108] First, the CTC model sets the initial water spray amount of the laminar cooling and sets the measured sampling and calculation period. As is known, the initial water spray amount of the laminar cooling is generally set to an empirical value in the CTC model, and thus will not be described herein. The set period unit is 5 meters per one, and the number of periods n = 780 / 5 = 156 for the measured sampling and calculation of the entire length of the strip, and the limit deviation value is 1 (unit: degree Celsius). The entire length of the strip is measured and sampled one by one for 156 periods, and the finishing exit temperature, thickness, width, speed, coiling inlet temperature T 实 and the water spray amount of the laminar cooling are calculated and predicted one by one, and the predicted temperature T 预 of the strip before coiling in each period is calculated and predicted.

[0109] As is also known, T 预 is generally calculated by the heat conduction, heat radiation, and heat convection of the strip inside, and the temperature drop of the strip from the finishing exit to the coiling inlet is calculated.

[0109] The heat conduction inside the strip is calculated using a differential equation, and the heat conduction calculation maintains the temperature of each node during the process of the strip from the heating furnace to the coiling, and the node distance varies depending on the thickness, and generally the distance of the center is greater than that of the surface, and the heat change between the nodes is calculated by the one-dimensional conduction equation as follows:

[0110]

[0111] wherein:

[0112] Q l→l+1 : heat flow rate from node I to node I+1,

[0113] k: heat conduction coefficient,

[0114] A l→l+1 : area between node I and I+1,

[0115] T i : temperature at node I,

[0116] d: distance between nodes.

[0117] The heat change due to the radiation of the upper and lower parts of the strip and the surrounding environment is calculated using the Stefan-Boltzmann equation as follows:

[0118]

[0119] wherein:

[0120] ε piece : heat radiation degree

[0121] A piece : radiation rate

[0122] T surround : ambient temperature

[0123] T surf Surface temperature of rolled parts

[0124] Convective heat transfer between strip steel and cooling water refers to the heat transfer between a fluid and a solid. Convective heat transfer mainly occurs between laminar cooling water and the upper and lower surfaces of the strip steel. The amount of convective heat transfer is calculated using Newton's equation of cooling as follows:

[0125] Q p =-Q w =-h w A w (T surf -T w ),

[0126] in:

[0127] h w Heat exchange coefficient

[0128] T w Cooling water temperature

[0129] T surf Surface temperature of strip steel

[0130] Calculate and predict the temperature T before strip coiling. 预 At the same time, perform the following steps:

[0131] 1) Calculate the strip coiling control temperature Tcontrol in the same cycle as the predicted strip coiling temperature Tpre;

[0132] T 控 =T 目 +T 补 (1),

[0133] In equation (1), T 目 The target temperature for strip coiling is set at 570℃, T 补 It is related to the predicted temperature T before strip coiling. 预 The compensated temperature of the strip in the laminar cooling section during the same cycle; T 补 Calculate according to the following formula (2):

[0134] T 补 =k*X+t, (2),

[0135] In equation (2), X is the cumulative length of the strip during operation, k is the temperature per unit length during the operation of the strip, and t is the fine-tuning temperature during the operation of the strip.

[0136] A. When the strip starts running without sampling, X = 0, t = 0, then the initial temperature compensation T 补= 0, T 控 = T 目 ;

[0137] B.After the strip running start period sampling, the unit length temperature k and the fine adjustment temperature t in each period are revalued according to the unit length temperature value and the fine adjustment temperature value calculated in the previous period according to the following formula (3) and (4), and the initial unit length temperature k and the fine adjustment temperature t are both set to zero,

[0138] k = k 前 + (k 实 - k 预 )*g (3),

[0139] t = t 前 + (t 实 - t 预 )*g (4),

[0140] wherein k 实 and t 实 are the unit length temperature and the fine adjustment temperature calculated according to the measured strip coiling inlet temperature in the current period, k 预 and t 预 are the unit length and the fine adjustment temperature calculated according to the predicted temperature before coiling, k 前 and t 前 are the unit length temperature and the fine adjustment temperature calculated in the previous period, and g is a fixed coefficient taking 0.3, k 实 , t 实 , k 预 and t 预 are calculated according to the following formula (5), (6), (7) and (8);

[0141] k 实 = ((n*∑(X*T 实 )) - (∑X*∑T 实 )) / ((n*∑(X*X)) - (∑X*∑X)) (5),

[0142] t 实 = (T 实 - (k 实 *X)) / n (6),

[0143] k 预 = ((n*∑(X*T 预 )) - (∑X*∑T 预 )) / ((n*∑(X*X)) - (∑X*∑X)) (7),

[0144] t 预 = (T 预 - (k预 X)) / n (8),

[0145] In the above equations (5), (6), (7) and (8), n is the number of cycles = 156;

[0146] 2) The absolute value Δt of the difference between the calculated coiling pre-forecast temperature T 预 of the strip in the same cycle and the controlled temperature T 控 of the strip before coiling is compared with the set limit deviation value,

[0147] A. When Δt is less than the limit deviation value, the laminar cooling water spray amount of the previous cycle is kept unchanged;

[0148] B. When Δt is greater than the limit deviation value,

[0149] If T 预 is greater than T 控 , the laminar cooling water spray amount of the previous cycle is increased until Δt is less than the limit deviation value, and the increased laminar cooling water spray amount is taken as the newly set laminar cooling water spray amount of the current cycle (or the present cycle); if T 预 is less than T 控 , the laminar cooling water spray amount of the previous cycle is decreased until Δt is less than the limit deviation value, and the decreased laminar cooling water spray amount is taken as the newly set laminar cooling water spray amount of the current cycle (or the present cycle);

[0150] 3) In each cycle, steps 1) and 2) are repeated until all the cycles for the full length of the strip are completed and the process is ended.

[0151] Example Two

[0152] The hot-rolled strip coiling temperature control method of this example is also for the same strip as in Example One, and the specific steps are different from those of Example One in that:

[0153] According to the running speed of the strip, it is divided into four speeds of uniform speed, speed-up, high speed and deceleration, and the running of the strip in the laminar cooling section is divided into five running sections of uniform speed head section, uniform speed section, speed-up section, high speed section and deceleration section. Accordingly:

[0154] The coiling pre-forecast temperature T 预 of the strip is divided into five kinds, which are the coiling pre-forecast temperature T 0预 calculated when the strip runs in the uniform speed head section, the coiling pre-forecast temperature T 1预 calculated when the strip runs in the uniform speed section except the uniform speed head section, the coiling pre-forecast temperature T 2预 calculated when the strip runs in the speed-up section, the coiling pre-forecast temperature T 3预and the calculated coiling front predicted temperature T when the strip runs in the deceleration section 4预 .

[0155] T 补 are divided into five kinds of compensation temperatures, which are the head compensation temperature T calculated when the strip runs in the uniform head section 0补 , the uniform compensation temperature T calculated when the strip runs in the uniform section except the uniform head section 1补 , the compensation temperature T calculated when the strip runs in the acceleration section 2补 , the compensation temperature T calculated when the strip runs in the high speed section 3补 and the compensation temperature T calculated when the strip runs in the deceleration section 4补 ;

[0156] The unit length temperature k and the fine adjustment temperature t are also divided into five kinds, which are the head unit length temperature k0 and the head fine adjustment temperature t0 calculated when the strip runs in the uniform head section, the uniform section unit length temperature k1 and the uniform section fine adjustment temperature t1 calculated when the strip runs in the uniform section except the uniform head section, the unit length temperature k2 and the fine adjustment temperature t2 calculated when the strip runs in the acceleration section, the unit length temperature k3 and the fine adjustment temperature t3 calculated when the strip runs in the high speed section, and the unit length temperature k4 and the fine adjustment temperature t4 calculated when the strip runs in the deceleration section;

[0157] In the first step, T 0补 , T 1补 , T 2补 , T 3补 and T 4补 are calculated according to the following formulas (9), (10), (11), (12) and (13), respectively,

[0158] When X≤S0<S1, T 0补 =t0; (9),

[0159] When X≤S1, T 1补 =X*k1+t1; (10),

[0160] When X≤S1+S2, T 2补 =S1*k1+(X-S1)*k2+t2; (11),

[0161] When X≤S1+S2+S3, T 3补 =S1*k1+S2*k2+(X-S1-S2)*k3+t3; (12),

[0162] When X≤S1+S2+S3+S4, T 4补 =S1*k1+S2*k2+S3*k3+(X-S1-S2-S3)*k4+t4; (13),

[0163] In formulae (9)-(13), S1 is the running length of the strip when running in the uniform speed section, S0 is the running length of the strip when running in the uniform speed head section (i.e. a section of the head of S1), S2 is the running length of the strip when running in the speed-up section, S3 is the running length of the strip when running in the high speed section, and S4 is the running length of the strip when running in the speed-down section;

[0164] k0, k1, k2, k3, k4 and t0, t1, t2, t3, t4 are respectively expanded as follows according to formulae (2) and (3) above:

[0165] k0 = k 0前 +(k 0实 -k 0预 )*g (14),

[0166] k1 = k 1前 +(k 1实 -k 1预 )*g (15),

[0167] k2 = k 2前 +(k 2实 -k 2预 )*g (16),

[0168] k3 = k 3前 +(k 3实 -k 3预 )*g (17),

[0169] k4 = k 4前 +(k 4实 -k 4预 )*g (18),

[0170] t0 = t 0前 +(t 0实 -t 0预 )*g (19),

[0171] t1 = t 1前 +(t 1实 -t 1预 )*g (20),

[0172] t2 = t 2前 +(t 2实 -t 2预 )*g (21),

[0173] t3 = t 3前 +(t 3实 -t 3预 )*g (22),

[0174] t4 = t 4前 +(t4实 -t 4预 )*g (23),

[0175] in formulae (14)-(23), k 0实 and t 0实 are respectively the unit length temperature and the fine tuning temperature of the current cycle calculated according to the measured coiling entry temperature of the strip steel running in the uniform speed head section, k 0预 and t 0预 are respectively the unit length and the fine tuning temperature of the current cycle calculated according to the pre-coiling temperature; k 1实 and t 1实 are respectively the unit length temperature and the fine tuning temperature of the current cycle calculated according to the measured coiling entry temperature of the strip steel running in the uniform speed section other than the uniform speed head section, k 1预 and t 1预 are respectively the unit length and the fine tuning temperature of the current cycle calculated according to the pre-coiling temperature; k 2实 and t 2实 are respectively the unit length temperature and the fine tuning temperature of the current cycle calculated according to the measured coiling entry temperature of the strip steel running in the speed-up section, k 2预 and t 2预 are respectively the unit length and the fine tuning temperature of the current cycle calculated according to the pre-coiling temperature; k 3实 and t 3实 are respectively the unit length temperature and the fine tuning temperature of the current cycle calculated according to the measured coiling entry temperature of the strip steel running in the high speed section, k 3预 and t 3预 are respectively the unit length and the fine tuning temperature of the current cycle calculated according to the pre-coiling temperature; k 4实 and t 4实 are respectively the unit length temperature and the fine tuning temperature of the current cycle calculated according to the measured coiling entry temperature of the strip steel running in the speed-down section, k 4预 and t 4预 are respectively the unit length and the fine tuning temperature of the current cycle calculated according to the pre-coiling temperature; k 0前 and t 0前 are respectively the unit length temperature and the fine tuning temperature of the previous cycle calculated when the strip steel runs in the uniform speed head section, k 1前 and t 1前 are respectively the unit length temperature and the fine tuning temperature of the previous cycle calculated when the strip steel runs in the uniform speed section other than the uniform speed head section; k 2前 and t 2前 are respectively the unit length temperature and the fine tuning temperature of the previous cycle calculated when the strip steel runs in the speed-up section; k3前 and t 3前 These are the unit length temperature and fine-tuning temperature calculated in the previous cycle when the strip is running at high speed; k 4前 and t 4前 These are the unit length temperature and fine-tuning temperature calculated in the previous cycle when the strip is running in the deceleration section.

[0176] k 0实 k 1实 k 2实 k 3实 k 4实 t 0实 t 1实 t 2实 t 3实 t 4实 and k 0预 k 1预 k 2预 k 3预 k 4预 t 0预 t 1预 t 2预 t 3预 t 4预 Expand the above equations (5)-(8) into the following equations (24)-(43):

[0177] k 0实 =((n*∑(X*T)) 0实 ))-(∑X*∑T 0实 )) / ((n*∑(X*X))-(∑X*∑X)) (24),

[0178] k 1实 =((n*∑(X*T)) 1实 ))-(∑X*∑T 1实 )) / ((n*∑(X*X))-(∑X*∑X)) (25),

[0179] k 2实 =((n*∑(X*T)) 2实 ))-(∑X*∑T 2实 )) / ((n*∑(X*X))-(∑X*∑X)) (26),

[0180] k 3实 =((n*∑(X*T)) 3实 ))-(∑X*∑T 3实 )) / ((n*∑(X*X))-(∑X*∑X)) (27),

[0181] k 4实 =((n*∑(X*T)) 4实 ))-(∑X*∑T4实 )) / ((n*∑(X*X))-(∑X*∑X)) (28),

[0182] t 0实 =(T 0实 -(k 0实 *X)) / n (29),

[0183] t 1实 =(T 1实 -(k 1实 *X)) / n (30),

[0184] t 2实 =(T 2实 -(k 2实 *X)) / n (31),

[0185] t 3实 =(T 3实 -(k 3实 *X)) / n (32),

[0186] t 4实 =(T 4实 -(k 4实 *X)) / n (33),

[0187] k 0预 =((n*∑(X*T 0预 ))-(∑X*∑T 0预 )) / ((n*∑(X*X))-(∑X*∑X)) (34),

[0188] k 1预 =((n*∑(X*T 1预 ))-(∑X*∑T 1预 )) / ((n*∑(X*X))-(∑X*∑X)) (35),

[0189] k 2预 =((n*∑(X*T 2预 ))-(∑X*∑T 2预 )) / ((n*∑(X*X))-(∑X*∑X)) (36),

[0190] k 3预 =((n*∑(X*T 3预 ))-(∑X*∑T 3预 )) / ((n*∑(X*X))-(∑X*∑X)) (37),

[0191] k 4预 =((n*∑(X*T 4预 ))-(∑X*∑T 4预)) / ((n*∑(X*X))-(∑X*∑X)) (38),

[0192] t 0预 =(T 0预 -(k 0预 *X)) / n (39),

[0193] t 1预 =(T 1预 -(k 1预 *X)) / n (40),

[0194] t 2预 =(T 2预 -(k 2预 *X)) / n (41),

[0195] t 3预 =(T 3预 -(k 3预 *X)) / n (42),

[0196] t 4预 =(T 4预 -(k 4预 *X)) / n (43),

[0197] In equations (24)-(43) above, T 0实 The measured strip coiling inlet temperature (T) is when the strip is running at a constant speed in the head section. 0预 This is the predicted temperature before coiling, calculated when the strip is running at a constant speed in the head section; T 1实 The measured strip coiling inlet temperature (T) is the actual temperature of the strip at the coiling inlet when the strip is running at a constant speed (excluding the head section). 1预 T1 is the predicted temperature before coiling, calculated when the strip is running at a constant speed (excluding the head section); T2 is the actual measured temperature at the coiling inlet when the strip is running at an increasing speed. 2预 This is the predicted temperature before coiling, calculated when the strip is running in the speed-up section; T 3实 The measured strip coiling inlet temperature (T) is when the strip is running at high speed. 3预 This is the predicted temperature before coiling, calculated when the strip is running at high speed; T 4实 The measured strip coiling inlet temperature (T) is when the strip is running in the deceleration section. 4预 It is the predicted temperature before coiling, calculated when the strip is running in the deceleration section.

[0198] This embodiment attempts to use one of the parameters k from the above parameters. 1实 Taking the temperature per unit length of the strip (calculated based on the measured entry temperature of the strip coiling in the uniform speed section) as an example, the specific calculation is as follows:

[0199] k 1实 =((n*∑(X*T))1实 ))-(∑X*∑T 1实 )) / ((n*∑(X*X))-(∑X*∑X))

[0200] Where k 1实 The number of sampling periods for each stage are: [4, 56, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21];

[0201] The calculated values ​​of ∑X for the strip running at a constant speed are: [15, 35, 60, 90, 125, 165, 210, 260, 315, 375, 440, 510, 585, 665, 750, 840, 935, 1035];

[0202] ∑T 1实 The calculated values ​​are: [585, 1174, 1762, 2352, 2940, 3531, 4120, 4710, 5300, 5887, 6467, 7050, 7632, 8216, 8803, 9389, 9974, 10559];

[0203] ∑(X*T 1实 The calculated values ​​are: [8775, 20555, 35255, 52955, 73535, 97175, 123680, 153180, 185630, 220850, 258550, 299360, 343010, 389730, 439625, 492365, 547940, 606440];

[0204] The calculated values ​​of ∑(X*X) are: [225, 1450, 5050, 13150, 28775, 56000, 100100, 167700, 266925, 407550, 601150, 861250, 1203475, 1645700, 2208200, 2913800, 3788025, 4859250];

[0205] Then k 1实 =(21*606440-1035*10559) / (21*4859250-1035*1035)=0.017893

[0206] The calculation process for other parameters is the same as k. 1实 Similar to this, so I will not go into details here.

[0207] According to T 0补 T 1补 T 2补 T 3补 and T4补 According to (1), five kinds of strip pre-coiling control temperatures are obtained respectively: the strip pre-coiling control temperature T 0控 calculated when the strip runs in the uniform speed section except the uniform speed head section 1控 calculated when the strip runs in the speed-up section 2控 calculated when the strip runs in the high speed section 3控 and the strip pre-coiling control temperature T 4控 calculated when the strip runs in the speed-down section 0控 , T 1控 , T 2控 , T 3控 and T 4控 are calculated respectively according to the following formulas (44)-(48):

[0208] T 0控 = T 0补 (44),

[0209] T 1控 = T 目 + T 1补 (45),

[0210] T 2控 = T 目 + T 2补 (46),

[0211] T 3控 = T 目 + T 3补 (47),

[0212] T 4控 = T 目 + T 4补 (48),

[0213] In the second step, the absolute values Δt are five kinds respectively: the absolute value Δt0 calculated when the strip runs in the uniform speed head section, the absolute value Δt1 calculated when the strip runs in the uniform speed section except the uniform speed head section, the absolute value Δt2 calculated when the strip runs in the speed-up section, the absolute value Δt3 calculated when the strip runs in the high speed section, and the absolute value Δt4 calculated when the strip runs in the speed-down section, Δt0, Δt1, Δt2, Δt3 and Δt4 are calculated respectively according to the following formulas (49)-(53):

[0214] Δt0= |T 0预 -T 0控 (49),

[0215] Δt1= |T 1预 -T 1控(50),

[0216] Δt2 = |T 2预 -T 2控 (51),

[0217] Δt3 = |T 3预 -T 3控 (52),

[0218] Δt4 = |T 4预 -T 4控 | (53).

[0219] According to the current period, the strip is running in one of the five running sections, and the corresponding measured values of the coiling inlet temperature T 0实 , T 1实 , T 2实 , T 3实 and T 4实 of the strip running in one of the five running sections (one running section) in the current period are obtained; and the following data of the strip running in one of the five running sections (one running section) in the current period are calculated accordingly:

[0220] T 0预 , T 1预 , T 2预 , T 3预 and T 4预 ,

[0221] k 0实 , k 1实 , k 2实 , k 3实 and k 4实 ,

[0222] t 0实 , t 1实 , t 2实 , t 3实 and t 4实 ,

[0223] k 0预 , k 1预 , k 2预 , k 3预 and k 4预 ,

[0224] t 0预 , t 1预 , t 2预 , t 3预 and t 4预 ,

[0225] k0, k1, k2, k3 and k4,

[0226] one of t0, t1, t2, t3 and t4,

[0227] one of T0sup, T1sup, T2sup, T3sup and T4sup,

[0228] one of T0con, T1con, T2con, T3con and T4con;

[0229] In the step 2), one of the absolute values Δt0, Δt1, Δt2, Δt3 and Δt4 of the difference between one of the calculated strip pre-rolling temperatures T 0预 , T 1预 , T 2预 , T 3预 and T 4预 in the same period and one of the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 is calculated, and finally one of the Δt0, Δt1, Δt2, Δt3 and Δt4 is compared with and controlled according to a set limit deviation value as follows:

[0230] A. When one of the absolute values Δt0, Δt1, Δt2, Δt3 and Δt4 is less than the limit deviation value 1 degree, the laminar cooling water spray amount of the previous period is kept unchanged;

[0231] B. When one of the absolute values Δt0, Δt1, Δt2, Δt3 and Δt4 is greater than the limit deviation value 1 degree,

[0232] If one of the T 0预 , T 1预 , T 2预 , T 3预 and T 4预 is greater than one of the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 , i.e. if T 0预 > T 0控 , T 1预 > T 1控 , T 2预 > T 2控 , T 3预 > T 3控 or T 4预 > T 4控 , the laminar cooling water spray amount of the previous period is increased until one of the Δt0, Δt1, Δt2, Δt3 and Δt4 is less than the limit deviation value, and the increased laminar cooling water spray amount is taken as the newly set laminar cooling water spray amount of the current period (or the present period), if T 0预 , T 1预 , T2预 T 3预 and T 4预 One of them is less than T. 0控 T 1控 T 2控 T 3控 and T 4控 One of them, that is, if T 0预 <T 0控 T 1预 <T 1控 T 2预 <T 2控 T 3预 <T 3控 Or T 4预 <T 4控 If the laminar cooling water spray volume of the previous cycle is reduced until one of Δt0, Δt1, Δt2, Δt3 and Δt4 is less than the limit deviation value, the reduced laminar cooling water spray volume will be used as the newly set laminar cooling water spray volume for the current cycle (or this cycle).

[0233] In this embodiment, the actual coiling temperature control of the strip running in the laminar flow cooling section is as follows: Figure 2 As shown, the unit length temperature k actually reflects the slope of the controlled temperature T before coiling of the strip in the laminar cooling section. Furthermore, the slopes of the five different operating segments in the laminar cooling section are all different. That is, the unit length temperature k changes with the strip's operating speed; it varies not only with the sampling period but also with the strip's operating speed. This transforms the previous method, which lacked a single slope variation in the laminar cooling section without speed-based segmentation, into five different slope variations, allowing for more detailed analysis of the aforementioned parameters and improved calculation accuracy.

[0234] Since the strip is 780 meters long and there are 156 cycles, there are too many parameters to be measured and calculated in the entire process described above. Each of the above parameters has its own calculation formula or existing known calculation method. In addition, the specific numerical calculation process of the parameters is cumbersome and the amount of data is very large. Therefore, the above embodiments will not describe the specific numerical calculation process of all parameters.

[0235] The above description is merely a preferred embodiment of the present invention, but the present invention is not limited thereto. For example, the set target temperature for strip winding is not limited to 570°C, the set cycle is not limited to 5 meters / cycle, and the set limit deviation value is not limited to 1 degree. All equivalent substitutions or modifications made to the concepts and technical solutions of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for controlling the coiling temperature of a hot strip in a hot strip rolling process, which involves the whole length of the strip being rolled to coiling in a hot strip rolling line and using the laminar cooling control model of the line to set the initial water spraying amount of the laminar cooling and to set the period unit for the actual sampling and calculation, the number of periods n = the whole length of the strip / the period unit; the whole length of the strip is sampled and calculated according to the number of periods, and the finishing mill exit temperature, thickness, width, speed, coiling inlet temperature Tact and the water spraying amount of the laminar cooling of each period are obtained one by one, and the predicted temperature Tpre before the coiling of the strip in each period is calculated and predicted one by one; characterized in that: The following steps are performed simultaneously with the calculation and prediction of the Tpre: ​ 1) The control temperature Tcon before coiling of the strip is calculated for the same period as the Tpre according to the following formula (1): Tcon = Ttarget + Tcomp (1), in which formula (1), Ttarget is the set target temperature of the strip coiling, and Tcomp is the compensation temperature of the strip in the laminar cooling section for the same period as the Tpre; the Tcomp is calculated according to the following formula (2): Tcomp = k * X + t (2), in which formula (2), X is the cumulative length of the strip running, k is the unit length temperature when the strip is running, and t is the fine tuning temperature when the strip is running; A. When the strip starts running without sampling, X = 0, t = 0, then the initial temperature compensation Tcomp = 0, Tcon = Ttarget; B. After sampling at the beginning of the strip running period, the unit length temperature k and the fine tuning temperature t in each period are recalculated according to the unit length temperature value and the fine tuning temperature value calculated in the previous period according to the following formulas (3) and (4), and the initial unit length temperature k and the fine tuning temperature t are both set to zero, k = kprevious + (kactual - kpredicted) * g (3), t = tprevious + (tactual - tpredicted) * g (4), in which formula, kactual and tactual are the unit length temperature and the fine tuning temperature calculated according to the actual measured strip coiling inlet temperature in the current period, kpredicted and tpredicted are the unit length and the fine tuning temperature calculated according to the predicted temperature before coiling, kprevious and tprevious are the unit length temperature and the fine tuning temperature calculated in the previous period, and g is a fixed coefficient; kactual, tactual, kpredicted and tpredicted are calculated according to the following formulas (5), (6), (7) and (8): kactual = ((n * ∑(X * Tactual)) - (∑X * ∑Tactual)) / ((n * ∑(X * X)) - (∑X * ∑X)) (5), tactual = (Tactual - (kactual * X)) / n (6), kpredicted = ((n * ∑(X * Tpredicted)) - (∑X * ∑Tpredicted)) / ((n * ∑(X * X)) - (∑X * ∑X)) (7), tpredicted = (Tpredicted - (kpredicted * X)) / n (8); 2) The absolute value Δt of the difference between the predicted temperature Tpre before coiling of the strip and the control temperature Tcon before coiling of the strip in the same period is compared with the set limit deviation value and controlled as follows: A. When Δt is less than the limit deviation value, the laminar cooling water spraying amount of the previous period is kept unchanged; B. When Δt is greater than the limit deviation value, if Tpre is greater than Tcon, the laminar cooling water spraying amount of the previous period is increased until Δt is less than the limit deviation value, and the increased laminar cooling water spraying amount is taken as the newly set laminar cooling water spraying amount in the current period; if Tpre is less than Tcon, the laminar cooling water spraying amount of the previous period is reduced until Δt is less than the limit deviation value, and the reduced laminar cooling water spraying amount is taken as the newly set laminar cooling water spraying amount in the current period; 3) repeating steps 1) and 2) in each cycle until the end of the full length of the strip is measured and calculated after the completion of all cycle numbers; according to the strip running speed, it is divided into four speeds of uniform speed, speed-up, high speed and deceleration, and the strip running in the laminar cooling section is divided into five running sections of uniform speed head section, uniform speed section, speed-up section, high speed section and deceleration section, accordingly: The pre-rolling temperature Tpre is divided into five kinds, which are the pre-rolling temperature T0pre calculated when the strip runs in the uniform speed head section, the pre-rolling temperature T1pre calculated when the strip runs in the uniform speed section except the uniform speed head section, the pre-rolling temperature T2pre calculated when the strip runs in the speed-up section, the pre-rolling temperature T3pre calculated when the strip runs in the high speed section and the pre-rolling temperature T4pre calculated when the strip runs in the deceleration section; The Tcomp is divided into five kinds of compensation temperatures, which are the head compensation temperature T0comp calculated when the strip runs in the uniform speed head section, the uniform speed compensation temperature T1comp calculated when the strip runs in the uniform speed section except the uniform speed head section, the compensation temperature T2comp calculated when the strip runs in the speed-up section, the compensation temperature T3comp calculated when the strip runs in the high speed section and the compensation temperature T4comp calculated when the strip runs in the deceleration section; The unit length temperature k and the fine adjustment temperature t are divided into five kinds, which are: the head unit length temperature k0 and the head fine adjustment temperature t0 calculated when the strip runs in the uniform speed head section, the uniform speed section unit length temperature k1 and the uniform speed section fine adjustment temperature t1 calculated when the strip runs in the uniform speed section except the uniform speed head section, the unit length temperature k2 and the fine adjustment temperature t2 calculated when the strip runs in the speed-up section, the unit length temperature k3 and the fine adjustment temperature t3 calculated when the strip runs in the high speed section, and the unit length temperature k4 and the fine adjustment temperature t4 calculated when the strip runs in the deceleration section; In the first step, the T0comp, T1comp, T2comp, T3comp and T4comp are calculated according to the following formulas (9), (10), (11), (12) and (13) respectively, X < S0 < S1, T 0补 = t0; (9), X < S1, T 1补 = X * k1 + t1; (10), X < S1 + S2, T 2补 = S1 * k1 + (X - S1) * k2 + t2; (11), X < S1 + S2 + S3, T 3补 = S1 *k1 + S2 *k2 + (X - S1 - S2) *k3 + t3; (12), X < S1+S2+S3+S4, T 4补 =S1*k1+S2*k2+S3*k3+(X-S1-S2-S3)*k4+t4; (13), In formulas (9)-(13), S1 is the running length of the strip running in the uniform speed section, S0 is the running length of the strip running in the uniform speed head section, S2 is the running length of the strip running in the speed-up section, S3 is the running length of the strip running in the high speed section, and S4 is the running length of the strip running in the deceleration section; The k0, k1, k2, k3, k4 and t0, t1, t2, t3, t4 are expanded according to the above formulas (3) and (4) as follows: k0= k 0前 + (k 0实 - k 0预 ) * g (14), k1 = k 1前 + (k 1实 - k 1预 ) * g (15), k2 = k 2前 + (k 2实 - k 2预 ) * g (16), k3 = k 3前 + (k 3实 - k 3预 ) * g (17), k4 = k 4前 + (k 4实 - k 4预 ) * g (18), t0 = t 0前 + (t 0实 - t 0预 ) * g (19), t1 = t 1前 + (t 1实 - t 1预 ) * g (20), t2 = t 2前 + (t 2实 - t 2预 ) * g (21), t3 = t 3前 + (t 3实 - t 3预 ) * g (22), t4 = t 4前 + (t 4实 - t 4预 ) * g (23), In formulae (14)-(23), k 0实 and t 0实 are the unit length temperature and the fine tuning temperature respectively calculated according to the measured coiling entry temperature of the current cycle when the strip is running in the uniform speed head section, k 0预 and t 0预 are the unit length and the fine tuning temperature respectively calculated according to the predicted temperature before coiling of the current cycle when the strip is running in the uniform speed head section; k 1实 and t 1实 are the unit length temperature and the fine tuning temperature respectively calculated according to the measured coiling entry temperature of the current cycle when the strip is running in the uniform speed section other than the uniform speed head section, k 1预 and t 1预 are the unit length and the fine tuning temperature respectively calculated according to the predicted temperature before coiling of the current cycle when the strip is running in the uniform speed section other than the uniform speed head section; k 2实 and t 2实 are the unit length temperature and the fine tuning temperature respectively calculated according to the measured coiling entry temperature of the current cycle when the strip is running in the speed-up section, k 2预 and t 2预 are the unit length and the fine tuning temperature respectively calculated according to the predicted temperature before coiling of the current cycle when the strip is running in the speed-up section; k 3实 and t 3实 are the unit length temperature and the fine tuning temperature respectively calculated according to the measured coiling entry temperature of the current cycle when the strip is running in the high speed section, k 4实 and t 4实 are the unit length and the fine tuning temperature respectively calculated according to the predicted temperature before coiling of the current cycle when the strip is running in the high speed section; k 4预 and t 4预 are the unit length temperature and the fine tuning temperature respectively calculated according to the measured coiling entry temperature of the current cycle when the strip is running in the speed-down section, k 0前 and t 0前 are the unit length and the fine tuning temperature respectively calculated according to the predicted temperature before coiling of the current cycle when the strip is running in the speed-down section; k 1前 and t 1前 are the unit length temperature and the fine tuning temperature respectively calculated according to the measured coiling entry temperature of the current cycle when the strip is running in the uniform speed head section, k 2前 and t 2前 are the unit length and the fine tuning temperature respectively calculated according to the predicted temperature before coiling of the current cycle when the strip is running in the uniform speed head section; k 3前 and t 3前 are the unit length temperature and the fine tuning temperature respectively calculated according to the measured coiling entry temperature of the current cycle when the strip is running in the uniform speed section other than the uniform speed head section, k 4前 and t 4前 respectively, are the unit length temperature and fine tuning temperature of the previous cycle calculation when the strip is running in the deceleration section; said k 0实 , k 1实 , k 2实 , k 3实 , k 4实 , t 0实 , t 1实 , t 2实 , t 3实 , t 4实 and k 0预 , k 1预 , k 2预 , k 3预 , k 4预 , t 0预 , t 1预 , t 2预 , t 3预 , t 4预 are expanded as follows (24) - (43) respectively according to the above equations (5) - (8): k 0实 = ((n *∑(X*T 0实 )) - (∑X*∑T 0实 )) / ((n *∑(X*X)) - (∑X*∑X)) (24), k 1实 = ((n *∑(X*T 1实 )) - (∑X*∑T 1实 )) / ((n *∑(X*X)) - (∑X*∑X)) (25), k 2实 = ((n *∑(X*T 2实 )) - (∑X*∑T 2实 )) / ((n *∑(X*X)) - (∑X*∑X)) (26), k 3实 = ((n *∑(X*T 3实 )) - (∑X*∑T 3实 )) / ((n *∑(X*X)) - (∑X*∑X)) (27), k 4实 = ((n * ∑(X * T 4实 )) - (∑X * ∑T 4实 )) / ((n * ∑(X * X)) - (∑X * ∑X)) (28), t 0实 = (T 0实 -(k 0实 *X)) / n (29), t 1实 = (T 1实 -(k 1实 *X)) / n (30), t 2实 = (T 2实 -(k 2实 *X)) / n (31), t 3实 = (T 3实 -(k 3实 *X)) / n (32), t 4实 = (T 4实 - (k 4实 *X)) / n (33), k 0预 = ((n *∑(X*T 0预 )) - (∑X*∑T 0预 )) / ((n *∑(X*X)) - (∑X*∑X)) (34), k 1预 = ((n *∑(X*T 1预 )) - (∑X*∑T 1预 )) / ((n *∑(X*X)) - (∑X*∑X)) (35), k 2预 = ((n *∑(X*T 2预 )) - (∑X*∑T 2预 )) / ((n *∑(X*X)) - (∑X*∑X)) (36), k 3预 = ((n *∑(X*T 3预 )) - (∑X*∑T 3预 )) / ((n *∑(X*X)) - (∑X*∑X)) (37), k 4预 = ((n * ∑(X * T 4预 )) - (∑X * ∑T 4预 )) / ((n * ∑(X * X)) - (∑X * ∑X)) (38), t 0预 = (T 0预 -(k 0预 *X)) / n (39), t 1预 = (T 1预 -(k 1预 *X)) / n (40), t 2预 = (T 2预 -(k 2预 *X)) / n (41), t 3预 = (T 3预 -(k 3预 *X)) / n (42), t 4预 = (T 4预 -(k 4预 *X)) / n (43), In the above equations (24)-(43), T 0实 is the measured strip coiling entry temperature, T 0预 is the calculated pre-coiling forecast temperature; T 1实 is the measured strip coiling entry temperature, T 1预 is the calculated pre-coiling forecast temperature; T 2实 is the measured strip coiling entry temperature, T 2预 is the calculated pre-coiling forecast temperature; T 3实 is the measured strip coiling entry temperature, T 3预 is the calculated pre-coiling forecast temperature; T 4实 is the measured strip coiling entry temperature, T4preis the calculated pre-coiling forecast temperature; According to the T 0补 , T 1补 , T 2补 , T 3补 and T 4补 , the five kinds of strip pre-coiling control temperatures are respectively obtained by expanding the formula (1): the strip pre-coiling control temperature T 0控 calculated when the strip runs in the uniform speed head section 1控 calculated when the strip runs in the uniform speed section except the uniform speed head section 2控 calculated when the strip runs in the speed-up section 3控 calculated when the strip runs in the high speed section 4控 and the strip pre-coiling control temperature T 0控 calculated when the strip runs in the speed-down section 1控 , T 2控 , T 3控 and T 4控 are respectively calculated according to the following formulae (44)-(48): T 0控 = T 目 + T 0补 (44), T 1控 = T 目 + T 1补 (45), T 2控 = T 目 + T 2补 (46), T 3控 = T 目 + T 3补 (47), T 4控 = T 目 + T 4补 (48), In the second step, the absolute values Δt are five respectively: the absolute value Δt0 calculated when the strip runs in the uniform head section, the absolute value Δt1 calculated when the strip runs in the uniform section other than the uniform head section, the absolute value Δt2 calculated when the strip runs in the acceleration section, the absolute value Δt3 calculated when the strip runs in the high speed section, and the absolute value Δt4 calculated when the strip runs in the deceleration section 4， The Δt0, Δt1, Δt2, Δt3 and Δt4 are calculated respectively according to the following formulas (49)-(53): At0 = |T 0预 - T 0控 | (49), Δti = |T 1预 - T 1控 | (50), Δt2 = |T 2预 - T 2控 | (51), Δt3 = |T 3预 - T 3控 | (52), Δt4 = |T 4预 - T 4控 | (53), According to the current cycle occurring when the strip steel runs in one of the five running sections, the corresponding measured T 实 , and the corresponding calculation of T 预 , k 实 , t 实 , k 预 , t 预 , k, t, T 补 , and T 控 of the strip steel running in one of the five running sections in the current cycle.

2. The method of claim 1, wherein: According to the current cycle occurring when the strip is running in one of the five operating sections, the corresponding measured values are obtained for the coiling inlet temperature T 0实 , T 1实 , T 2实 , T 3实 and T 4实 of the strip running in one of the five operating sections in the current cycle; and the following data are calculated for the strip running in one of the five operating sections in the current cycle: The T 0预 , T 1预 , T 2预 , T 3预 and T 4预 one of, said k 0实 , k 1实 , k 2实 , k 3实 and k 4实 one of t 0实 , t 1实 , t 2实 , t 3实 , and t 4实 one of, said k 0预 , k 1预 , k 2预 , k 3预 and k 4预 one of, t 0预 , t 1预 , t 2预 , t 3预 , and t 4预 one of One of the k0, k1, k2, k3 and k4, One of the t0, t1, t2, t3 and t4, The T 0补 , T 1补 , T 2补 , T 3补 , and T 4补 one of, The T 0控 , T 1控 , T 2控 , T 3控 , and T 4控 one of; In the second step, one of the absolute values Δt0, Δt1, Δt2, Δt3 and Δt4 of the difference between one of the calculated strip forecast temperatures T 0预 , T 1预 , T 2预 , T 3预 and T 4预 calculated in the same cycle and one of the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 is calculated, and finally one of the Δt0, Δt1, Δt2, Δt3 and Δt4 is compared with a set limit deviation value and controlled as follows: A. When one of the Δt0, Δt1, Δt2, Δt3 and Δt4 is less than the limit deviation value, the laminar cooling water spraying amount of the previous cycle is kept unchanged; B. When one of the Δt0, Δt1, Δt2, Δt3 and Δt4 is greater than the limit deviation value, If one of the T 0预 , T 1预 , T 2预 , T 3预 and T 4预 is greater than one of the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 , respectively, the amount of the laminar cooling water spray of the previous cycle is increased until one of the Δt0, Δt1, Δt2, Δt3 and Δt4 is less than the limit deviation value, and the increased amount of the laminar cooling water spray is set as the new amount of the laminar cooling water spray of the current cycle; If one of the T 0预 , T 1预 , T 2预 , T 3预 and T 4预 is less than one of the T 0控 , T 1控 , T 2控 , T 3控 and T 4控 , respectively, the amount of the laminar cooling water spray of the previous cycle is reduced until one of Δt0, Δt1, Δt2, Δt3 and Δt4 is less than a limit deviation value, and the reduced amount of the laminar cooling water spray is set as the new amount of the laminar cooling water spray of the current cycle.

3. The method of controlling the coiling temperature of a hot rolled strip steel according to claim 1 or 2, characterized in that: The setting cycle unit is 5 meters per unit, the fixed coefficient g is 0.3, and the limit deviation value is 1.

Images