An L1 tilt value dynamic adjustment method for improving rough rolling blank camber

Abstract

The application discloses a kind of L1 inclination value dynamic adjustment methods for improving rough rolling blank camber, the width center line deviation value of slab rolled by rough rolling mill is detected by width detector, the width center line deviation value is uploaded to L2 system, and the inclination setting value of camber is calculated by model and issued to L1 system by L2 system, and finally the automatic control process of camber is executed by L1 system.The application realizes L1 full-automatic control of rough rolling blank camber by L1 inclination value dynamic adjustment of rough rolling blank camber, avoids that operator frequently operates handle to correct the inclination of reduction, and can greatly reduce the frequent occurrence of large camber phenomenon or accident.

Description

TECHNICAL FIELD

[0001] The present application relates to the roughing mill technology of hot rolling equipment, more particularly, to a dynamic adjustment method of L1 inclination value for improving the camber of roughing billet. BACKGROUND

[0002] The camber of slab occurs after rolling, and the main reason is the asymmetric deformation during rolling. The main factors causing the asymmetric deformation include: temperature distribution in the width direction of slab, rolling mill execution accuracy, thickness difference in the width direction of slab, and actual centering accuracy of slab, etc. The camber of slab is the result of the comprehensive action of these factors.

[0003] The difficulty of controlling the camber of slab mainly lies in that there are many influencing factors, and some data in these influencing factors are unmeasurable or difficult to measure accurately. For example, temperature distribution in the width direction of slab, control accuracy of rolling mill, and thickness of both sides of slab, etc. Due to these uncertain factors, it is difficult to control the warping of slab through theoretical modeling and obtain good control effect.

[0004] At present, some patent documents propose to use the actual values of rolling forces on both sides of the roughing mill, the actual calculated values of roll gap, and the springback parameters on both sides of the rack as inputs, and after calculation, the size of the roll gap on one side or both sides of the rolling mill is adjusted to realize the correction of camber and wedge.

[0005] At present, the patents related to the camber of head include:

[0006] (1) The hot rolling strip roughing mill group camber and wedge automatic control method of Chinese invention patent with the authorized announcement number CN 101934292B, which proposes to use the actual values of rolling forces on both sides of the roughing mill, the actual calculated values of roll gap, and the springback parameters on both sides of the rack as inputs, and after accurate calculation, the size of the roll gap on one side or both sides of the rolling mill is adjusted to realize the correction of camber and wedge. The control method described in the present application can realize the control of camber and wedge without adding any intermediate billet camber shape detection device.

[0007] (2) The Chinese invention patent with the authorized publication number CN 102441576B, a method for automatically controlling the camber and wedge of the rough rolling intermediate slab of hot-rolled strip steel, discloses a new method for automatically controlling the camber and wedge of the rough rolling intermediate slab of hot-rolled strip steel, which is applied to a hot-rolled reversible rough rolling mill train. The application discloses two technologies: one is a model control technology, and the other is a center line offset feedback control technology. The model control is to take the actual values of the rolling forces on both sides of the rough rolling mill, the actual calculated values of the roll gap, and the springback parameters on both sides of the rack as inputs, and to obtain the horizontal adjustment amount of the roll gap on one side or both sides through accurate calculation; the center line offset feedback control technology is to calculate the horizontal adjustment amount of the roll gap on both sides by processing the center line offset signal detected by the width detector. The two technologies can well control the camber and wedge problems after being reasonably combined. The control method disclosed in the invention avoids adding expensive and difficult-to-maintain intermediate slab wedge and camber detection devices.

[0008] (3) The Chinese invention patent with the authorized publication number CN 100566866C, a control method for the camber of the rough rolling intermediate slab, adjusts the camber of the slab by controlling the position of the side guide plate and the pressure of the side guide plate.

[0009] (4) The Chinese invention patent with the authorized publication number CN 103752623B, an automatic control method for improving the camber of the rough rolling intermediate slab, the control method includes two parts: setting the roll gap inclination adjustment value of the current pass and correcting the roll gap inclination adjustment value of the camber of the outgoing slab of the previous pass. The former can be calculated from the analytical model according to the set rolling force of the current pass, the set outlet thickness, the set values of the roll gaps on both sides, the zero-adjusted rolling force, and the rigidity values of the rolling mills on both sides; the latter is calculated from the plastic deformation coefficient of the slab of the current pass and the actually measured rolling forces and the plastic deformation coefficient of the slab of the previous pass. The control method of the invention takes the actual process parameters on site as the input conditions, improves the effective control of the camber of the intermediate slab by the automatic control model, is convenient to operate, and can well improve the camber problem of the intermediate slab.

[0010] (5) The Chinese invention patent with the publication number CN 104162549B discloses a method and system for automatic control of intermediate slab camber in hot roughing mill. The technical solution measures the center line offset of the intermediate slab according to the plate width gauge. The length of the first side L1 and the length of the second side L2 of the intermediate slab outlet are calculated according to the center line offset through the side length calculation formula. The first thickness deviation Ahl and the second thickness deviation Ah2 of the two sides of the intermediate slab outlet are obtained by substituting L1 and L2 into the conversion formula. The roll gap adjustment value As is obtained by substituting Ahl and Ah2 into the roll gap adjustment value formula. The roll gap value between the work rolls of the mill is adjusted according to the roll gap adjustment value As. The work rolls of the mill can effectively control the shape of the intermediate slab camber during the next pass of the intermediate slab.

[0011] (6) Chinese patent application No. 201910810128.7 discloses a camber control method based on analysis of slab center line deviation, which includes installing a camber measuring instrument before and after the reciprocating mill. The slab center line curve is detected by the camber measuring instrument. The bending direction and bending degree are determined according to the center line deviation data curve. The roll gap correction amount is calculated. The roll gap correction amount is corrected according to the current pass width and reduction. L1 adjusts the roll gap difference on both sides of the horizontal roll according to the roll gap correction amount data. The subsequent pass is rolled on this basis, thereby realizing automatic feedback control of the camber. By analyzing the center line deviation data after slab rolling, the horizontal roll gap difference set value in the subsequent pass is automatically calculated, thereby reducing the bending degree of the camber, ensuring the flatness of the slab, reducing the labor intensity of the roughing operator, and improving the automation rate of roughing production.

[0012] The above disclosed patents (1), (2) are calculated according to the actual values of the rolling force on both sides of the horizontal roller, the roll gap, and the mill spring, and the single-sided or double-sided roll gap adjustment amount of the horizontal roller; the disadvantage is that the mill stiffness is used in the calculation of the mill spring, and the rough rolling usually adopts electric reduction, so it is not realistic to obtain very accurate stiffness data, so that the calculated spring data is not very accurate. Patent (3) controls the camber by the side guide plates on both sides of the mill, which belongs to adjusting the camber by mechanical equipment. The disadvantage of this method is that it is extremely risky to correct the camber by the side guide plate, and it is easy to cause the steel to be stuck. Patent (4) is also calculated according to the rolling data, and the camber adjustment amount is obtained by a theoretical model. The disadvantage is the same as patents (1), (2), and the stiffness calculation is not accurate. Patent (5) calculates the length of the two sides of the slab, calculates the different extension of the two sides, and obtains the camber adjustment amount by a model. This method is relatively complex to calculate, and the influence of the reduction amount and the width of the slab on the camber control is not considered. Patent (6) solves the problem of the L2 automatic control of the rough rolling mill camber control technology to issue the roll gap correction amount, but for L1, there is still only one manual way, that is, the operator manually adjusts the roll gap inclination value of the horizontal roller according to the roll gap correction amount issued by the L2 automatic control of the rolling line, monitors the video and visually measures the slab shape, or manually adjusts the roll gap inclination value of the horizontal roller according to the slab center line deviation data fed back by the instrument side width instrument, to achieve the purpose of adjusting the camber at the outlet of the mill.

[0013] At present, there are three heating furnaces in the 1580 production line in the steel plant, and the length of each furnace and the distance from the rolling line are not quite the same, resulting in different slab temperatures drawn out of each furnace, and different camber conditions after rough rolling, such as the 1# furnace is curved in the working side direction, the 2# furnace is curved in the driving side direction, and the 3# furnace may be curved in the working side direction. Therefore, the operator needs to frequently operate the handle to correct the reduction inclination, so as to control the amplitude of the camber and ensure the product coil shape. Since the "1+N" operator position is simplified on the 1580 production line, the N multi-post operator needs to consider many operation points, and sometimes it is simply not possible to adjust, resulting in frequent large camber phenomena or accidents.

[0014] In combination with Figure 1 As shown in the figure, the current camber control is mainly manual control, and the basic process is as follows:

[0015] S1, the width detector detects the slab center line deviation data uploaded to the HMI picture of the L1 system (base material automation system);

[0016] S2, the operator observes the actual value of the rolled slab center line and estimates the adjustment value of the next slab;

[0017] S3, the operator manually adjusts the inclination value by operating the handle;

[0018] S4, adjust the manual operation APC button to set the roll gap on both sides;

[0019] S5, the roll gap setting value is executed, and the rolling mill starts to roll the steel.

[0020] However, there are still the following difficulties in realizing the automatic control of the L1 system:

[0021] 1. When the on-site camber is very large and exceeds the above-mentioned threshold value, it is not enough to control by relying on the inclination value adjustment, and other factors such as slab temperature and roll diameter temperature should be considered and optimized at the same time, so as to achieve better effect;

[0022] 2. After the inclination value adjustment is too large, it will lead to the difficulty in controlling the convexity of the finished product in the finishing process, and there is a hidden danger of quality problems;

[0023] 3. When the width measuring instrument fails, there is no center line deviation data uploaded to the L2 system (process calculation system);

[0024] 4. The side width instrument is affected by external water vapor, and the data is distorted or intermittent. SUMMARY

[0025] In view of the defects in the prior art, the purpose of the present application is to provide an L1 inclination value dynamic adjustment method for improving the rough rolling slab camber, which realizes the L1 full-automatic control of the rough rolling slab camber by dynamically adjusting the L1 inclination value of the rough rolling slab camber, avoids the frequent operation of the handle by the operator to correct the reduction inclination, and can greatly reduce the frequent occurrence of large camber phenomenon or accidents.

[0026] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0027] An L1 inclination value dynamic adjustment method for improving the rough rolling slab camber:

[0028] The width center line deviation value of the slab rolled by the rough rolling mill is detected by the width measuring instrument, the width center line deviation value is uploaded to the L2 system, the L2 system calculates the inclination setting value of the camber by the model and sends it to the L1 system, and finally the L1 system executes the automatic control process of the camber.

[0029] Preferably, the L1 system executing the automatic control process of the camber specifically includes the following steps:

[0030] S1, after the L1 system receives the inclination setting value, it is judged whether the inclination setting value exceeds the threshold value, if yes, the steel shifting action is performed and an alarm is given, if not, step S2 is entered;

[0031] S2, the inclination setting value of the roll gap is pre-set in the current pass;

[0032] S3, judging whether the preset process of step S2 exceeds the set time, if yes, alarming, if not, entering step S4;

[0033] S4, the electromagnetic clutch is closed to start executing the tilt setting value of the roll gap;

[0034] S5, starting the steel feeding to start rolling.

[0035] Preferably, the L1 system judges whether the tilt setting value exceeds the threshold value in step S1, and the judgment is specifically as follows:

[0036] The L1 system calculates the maximum value and the minimum value in real time according to the width center line deviation value, and when |maximum value-minimum value|>threshold value, the next steel feeding is stopped, an alarm is given and the semi-automatic adjustment mode is entered.

[0037] Preferably, the threshold value is a program fixed value of the L1 system, and the value is 3 mm.

[0038] Preferably, when the tilt setting value of the roll is abnormal, the L1 system gives an alarm and enters the semi-automatic adjustment mode.

[0039] Preferably, the set time in step S3 is 20 seconds.

[0040] The L1 tilt value dynamic adjustment method for improving the rough rolling blank camber provided by the application can realize the L1 full-automatic control of the rough rolling blank camber by dynamically adjusting the L1 tilt value of the rough rolling blank camber, avoid the frequent operation of the handle by the operator to correct the reduction tilt amount, and greatly reduce the frequent occurrence of the large camber phenomenon or accidents. In the existing mode, the manual control of the camber by the operator is random, and the cognition and operation experience are also inconsistent. For the center line deviation curve of the same steel, some operators think that the amplitude does not need to be manually intervened, but some operators think that the intervention is needed. After the application is adopted, the rules of adjustment realize computer control, the camber control has left behind the original manual extensive control, and has realized automatic and fine control, so as to lay a good technical foundation for the improvement of the plate shape at the outlet of the rough rolling mill. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 is a flowchart of the existing manual control of the camber;

[0042] Figure 2 is a flowchart of the L1 tilt value dynamic adjustment method of the application;

[0043] Figure 3 is a system architecture diagram of the L1 tilt value dynamic adjustment method of the application. DETAILED DESCRIPTION

[0044] In order to better understand the above technical solutions of the present application, the technical solutions of the present application are further illustrated below in combination with the drawings and examples.

[0045] In combination Figure 2 and Figure 3 As shown in the figure, the present application provides a dynamic adjustment method for L1 tilt value of rough rolling blank camber:

[0046] The width center line deviation value of the slab rolled by the rough rolling mill is detected by the width detector 1 (installed at the rear of the rough rolling mill), the width center line deviation value is uploaded to the L2 system 2 (process calculation system), the tilt setting value of the camber is calculated by the L2 system 2 through a model and is issued to the L1 system 3 (basic automation system), and finally the L1 system 3 executes the camber automatic control process.

[0047] In the HMI picture of the L1 system 3, when the AUTO mode is selected and then the L2 ALL mode is selected, the camber automatic control process of the L1 system 3 is entered. If the operator needs to semi-automatically adjust the tilt amount, the L1 ALL mode is selected to control by inputting the correction tilt amount in the data box (camber L1 semi-automatic control). If the operator needs to directly operate to manually adjust the tilt amount, the mode is automatically switched from AUTO to MAN (full manual mode).

[0048] The L1 system 3 executing the camber automatic control process specifically includes the following steps:

[0049] S1, after the L1 system 3 receives the tilt setting value, it is judged whether the tilt setting value exceeds the threshold value, if yes, the steel tilting action is performed and an alarm is given, if not, step S2 is entered;

[0050] S2, the tilt setting value of the roll gap is preset for the current pass, the electromagnetic clutch is opened, the electromagnetic clutch between the high-speed and low-speed press-down of the transmission side is disconnected, the electromagnetic clutch between the high-speed and low-speed press-down of the working side is connected, and the working side press-down mechanism executes the tilt setting value of the roll gap by using the low-speed press-down motor;

[0051] S3, it is judged whether the presetting process of step S2 exceeds the set time, if yes, an alarm is given, if not, step S4 is entered;

[0052] S4, when the tilt actual value of the roll gap reaches the tilt setting value of the roll gap, the electromagnetic clutch is closed, the clutches on both sides are opened, the low-speed press-down motor is disconnected, and the tilt setting value of the roll gap is executed by using two high-speed press-down motors on both sides;

[0053] S5, after the roll gap is in place, the steel is started to be fed and the rolling is started.

[0054] The slab center line deviation data detected by the width gauge 1 is continuously uploaded to the L2 system 2, and the L2 system 2 calculates the tilt value of the roll gap through a model, and then sends the tilt setting value of the camber of the next slab to the L1 system 3 as the camber of the next slab.

[0055] In step S1, the L1 system 3 judges whether the tilt setting value exceeds the threshold value, and the specific process is as follows:

[0056] The L1 system 3 calculates the maximum value and the minimum value in real time according to the width center line deviation value, and when |maximum value-minimum value|>threshold value, the next slab is stopped, an alarm is given, and a semi-automatic adjustment mode is entered.

[0057] The alarm mode is to display an alarm prompt: R1 / 2 Tilt Ref Overlimit (tilt setting value over limit) on the HMI screen.

[0058] The necessity of setting the alarm in this process is as follows: 1. When the camber is very large and exceeds the above-mentioned threshold value, it is not enough to control by adjusting the tilt value alone, and other factors such as slab temperature and roll diameter temperature should be considered and optimized at the same time to achieve better results. 2. After adjusting the tilt value too large, it will lead to difficulty in controlling the finished product crown in the finishing process, and there is a hidden danger of quality problems.

[0059] The threshold value is a fixed value of the program of the L1 system 3, and the value is 3 mm.

[0060] When the tilt setting value of the roll (R1 or R2) is abnormal (detected by the width gauge 1 as 999 mm), the L1 system 3 gives an alarm and enters a semi-automatic adjustment mode, and the slab performs a swing motion until the setting value is not equal to 999 mm, and the mode is allowed to return to the L1 full-automatic mode.

[0061] The alarm mode is to display an alarm prompt: ALARM CODE 999 on the HMI screen.

[0062] The necessity of setting the alarm in this process is as follows: 1. When the width gauge 1 fails, there is no center line deviation data uploaded to the L2 system 2. 2. The data of the width gauge 1 is distorted or intermittent due to external water vapor. After the occurrence of the above two problems, the full-automatic function of the camber cannot be realized, and the operator must be prompted to inform the equipment maintenance personnel to eliminate the fault through the 999 alarm.

[0063] In step S3, the setting time is 20 seconds, and if the setting action is not completed within 20 seconds, the L1 system 3 performs a swing motion and gives an alarm, and the alarm mode is to display an alarm prompt: R1 / 2 Tilt ACTTIMEOUT on the HMI screen.

[0064] The necessity of setting the alarm in this process is that, through experiments within the adjustment threshold, 20 seconds can complete the full automation. If full automation is not completed, there must be a problem with the equipment, and the operator needs to notify the equipment personnel to check and handle.

[0065] When the existing manual control of the sickle bend is used, the operator needs to adjust the tilt value of the roll gap about 20 times within 10 hours, while the tilt value of the whole roll gap using the L1 tilt value dynamic adjustment method of the present application is as many as about 225 times within 10 hours. As can be seen, before the present application, the manual control of the sickle bend by the operator is arbitrary, and the cognitive and operating experience is also inconsistent. For the center line deviation curve of the same piece of steel, some operators think that this amplitude does not need to be manually intervened, while some think that it needs to be intervened; some think that it needs to be adjusted by 2 mm, while some think that it needs to be adjusted by 4 mm. After the present application, the adjustment rule is realized by computer control. The number of times of adjustment of the tilt value of the automatic control of the sickle bend is more than 10 times of the original technology. The control of the sickle bend has said goodbye to the original manual extensive control, and has realized automatic and fine control, thus laying a good technical foundation for the improvement of the plate shape at the outlet of the rough rolling mill.

[0066] The following table is a comparison of the monthly average of the maximum value of the center line deviation of the R2 third pass outlet width before and after the implementation of the present application:

[0067]

[0068]

[0069] As can be seen from the above table, after the present application, the maximum value of the center line deviation of the R2 third pass outlet width is significantly reduced, the control of the sickle bend plate shape at the R2 outlet is greatly improved, and the occurrence of large sickle bend and accidents is effectively eliminated.

[0070] Those skilled in the art in this technical field should realize that the above embodiments are only used to illustrate the present application, and are not used as a limitation on the present application, and as long as the changes and modifications of the above described embodiments are within the scope of the spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A method for improving the dynamic adjustment of L1 tilt value of roughing mill camber, characterized in that: the width center line deviation value of the slab rolled by the roughing mill is detected by a width detector, the width center line deviation value is uploaded to the L2 system, the tilt setting value of the camber is calculated by the L2 system through a model and is issued to the L1 system, and finally the L1 system executes the automatic control process of the camber; the L1 system executing the automatic control process of the camber specifically comprises the following steps: S1, after the L1 system receives the tilt setting value, it is judged whether the tilt setting value exceeds a threshold value, if yes, a steel shifting action is performed and an alarm is given, and if no, step S2 is entered; in the step S1, the L1 system judges whether the tilt setting value exceeds the threshold value specifically as follows: the L1 system calculates the maximum value and the minimum value in real time according to the width center line deviation value, when |maximum value-minimum value|>threshold value, the next pass is stopped and an alarm is given, and a semi-automatic adjustment mode is entered; S2, the tilt setting value of the roll gap is preset at the beginning of the current pass; S3, it is judged whether the presetting process of step S2 exceeds a set time, if yes, an alarm is given, and if no, step S4 is entered; S4, the electromagnetic clutch is closed to start executing the tilt setting value of the roll gap; S5, the steel feeding is started and the rolling is started; the threshold value is a fixed value of the program of the L1 system, and the value is 3 mm; in the step S3, the set time is 20 seconds. ​ ​ ​ ​ ​ ​ ​ ​ ​ 2. The method of claim 1, wherein the L1 tilt value is dynamically adjusted to improve the roughing pass buckling. ​ 3. The method of claim 1, wherein the L1 tilt value is dynamically adjusted to improve the roughing mill edge bow. ​

Images