L1 semi-automatic adjustment preset control value method for improving strip steel camber deviation

Abstract

The invention discloses an L1 semi-automatic adjustment preset control value method for improving strip steel camber deviation, which comprises the following steps of: detecting a width center line deviation value of a plate blank rolled by a roughing mill by a width gauge, uploading the width center line deviation value to an L1 system, and displaying the width center line deviation value on an HMI (Human Machine Interface) by the L1 system. And a worker inputs the inclination value set value of each pass of the roughing mill on the HMI according to the width center line deviation value displayed on the HMI, and the camber semi-automatic control process is carried out. According to the method, semi-automatic control is manually carried out on each pass of camber based on the number of rolling passes of the roughing mill, the blank that full-automatic operation cannot be carried out is filled, the situation that an operator does not choose a manual mode is avoided, and the labor efficiency and the camber control precision are improved.

Description

Technical Field

[0001] The present invention relates to a rough rolling mill technology for hot rolling equipment, and more specifically to a method for semi-automatically adjusting a preset control value of L1 for improving a strip steel sickle bending deviation. Background Art

[0002] The main reason for the sickle bending of the slab after rolling is the asymmetric deformation during rolling. The main factors causing asymmetric deformation include: temperature distribution in the width direction of the slab, rolling mill execution accuracy, thickness difference on both sides in the width direction of the slab, actual centering accuracy of the slab, etc. The sickle bending of the slab is the result of the combined effect of these factors.

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

[0004] At present, some patent documents propose to use the actual value of the rolling force on both sides of the roughing mill, the actual calculated value of the roll gap, and the bounce parameters on both sides of the stand as inputs. After calculation, the roll gap size on one side or both sides of the mill is adjusted to achieve the correction of sickle and wedge. There are also patent documents that propose to adjust the sickle of the slab by controlling the position of the side guide and the pressure of the side guide.

[0005] The current patents related to the button head include:

[0006] (1) The Chinese invention patent with the authorization announcement number CN 101934292B is a method for automatically controlling the camber and wedge of a hot strip roughing mill. It is mentioned that the actual value of the rolling force on both sides of the roughing mill, the actual calculated value of the roll gap, and the bounce parameters on both sides of the frame are taken as inputs. After accurate calculation, the camber and wedge correction is finally achieved by adjusting the roll gap size on one side or both sides of the mill. The control method of the present invention can achieve camber and wedge control without adding any camber shape detection device for the intermediate billet.

[0007] (2) The Chinese invention patent with the authorization announcement number CN 102441576B, "Automatic control method for camber and wedge of intermediate billet in hot-rolled steel strip rough rolling", discloses a novel automatic control method for camber and wedge of intermediate billet in hot-rolled steel strip rough rolling, which is applied to hot-rolled reversible rough rolling mills. The application discloses two technologies: one is the model control technology, and the other is the feedback control technology for the centerline offset of the intermediate billet. The model control is to take the actual value of the rolling force on both sides of the rough rolling mill, the actual calculated value of the roll gap, and the bounce parameters on both sides of the frame as input, and obtain the horizontal adjustment amount of the roll gap on one side or both sides of the rolling mill through precise calculation; the other is the feedback control technology for the centerline offset, which is to calculate the horizontal adjustment amount on both sides of the rolling mill after special processing of the centerline offset signal of the slab detected by the width gauge. The reasonable combination of these two technologies can well control the camber and wedge problems. The control method described in the invention avoids the need to add expensive and difficult to maintain intermediate billet wedge and camber detection devices.

[0008] (3) A Chinese invention patent with authorization announcement number CN 100566866C discloses a method for controlling the camber of a rough rolling intermediate slab. The technical solution 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 authorization announcement number CN 103752623B is an automatic control method for improving the sickle bend of the rough rolling intermediate billet. The control method is divided into two parts: setting the roll gap tilt adjustment value of the current pass and correcting the roll gap tilt adjustment value of the exit sickle bend of the previous pass. The former can be calculated by the analytical model according to the set rolling force of the current pass, the set exit thickness, the roll gap setting value on both sides, the zero adjustment rolling force and the rolling mill stiffness value on both sides; the latter is calculated by the slab plastic deformation coefficient of the current pass and the measured rolling force and slab plastic deformation coefficient on both sides of the previous pass. The control method of the present invention uses the actual process parameters on site as input conditions, improves the automatic control model to effectively control the sickle bend of the intermediate billet, is convenient to operate, and can well improve the sickle bend problem of the intermediate billet.

[0010] (5) The Chinese invention patent with the authorization announcement number CN 104162549B is an automatic control method and system for the sickle camber of the intermediate billet of the hot rolling roughing mill. The technical solution obtains the center line offset of the intermediate billet according to the measurement of the slab width gauge; obtains the side length L1 of the first side and the side length L2 of the second side at the intermediate billet outlet according to the center line offset through the side length calculation formula; substitutes L1 and L2 into the conversion formula to obtain the first thickness deviation △h1 and the second thickness deviation △h2 on both sides of the intermediate billet outlet; substitutes △h1 and △h2 into the roll gap leveling value formula to obtain the roll gap leveling value △s; adjusts the roll gap value between the working rolls of the rolling mill according to the roll gap leveling value △s; so that the working rolls of the rolling mill can effectively control the sickle camber shape of the intermediate billet during the next pass of the intermediate billet.

[0011] (6) Chinese patent application No. 201910810128.7 discloses a camber control method based on analyzing the centerline deviation of the slab, which includes installing a camber measuring instrument before and after the reciprocating mill; using the camber measuring instrument to detect the centerline curve of the slab; judging the bending direction and degree according to the centerline deviation data curve; calculating the roll gap correction amount; correcting the roll gap correction amount according to the current pass width and the amount of reduction; L1 adjusts the roll gap difference on both sides of the horizontal roll according to the roll gap correction amount data, and the subsequent passes are rolled on this basis, thereby realizing automatic feedback control of the camber. It analyzes the centerline deviation data after the slab is rolled, and automatically calculates the roll gap difference setting value on both sides of the horizontal roll in the subsequent passes, thereby reducing the degree of camber bending, ensuring the straightness of the slab, reducing the labor intensity of the rough rolling operator, and improving the automation rate of rough rolling production.

[0012] The above-mentioned patents (1) and (2) calculate the adjustment amount of the single or double roll gap of the horizontal roll based on the actual values ​​of the rolling force on both sides of the horizontal roll, the roll gap, and the mill bounce. The disadvantage is that the mill stiffness is used in the mill bounce calculation, and the rough rolling usually adopts electric pressure reduction, and the stiffness test cannot be performed. Therefore, it is not realistic to obtain very accurate stiffness data, which leads to the calculated bounce data cannot be very accurate. Patent (3) controls the sickle bend by the side guide plates on both sides of the mill, which belongs to the adjustment of the sickle bend by mechanical equipment. The disadvantage of this method is that the risk of correcting the sickle bend by the side guide plates is very high, and it is easy to cause steel jamming. Patent (4) also calculates the sickle bend adjustment amount through a theoretical model based on rolling data. The disadvantage is the same as patents (1) and (2), that is, the stiffness calculation is inaccurate. Patent (5) calculates the length of the two sides of the slab, calculates the different extensions on both sides, and calculates the sickle bend adjustment amount through a model. This method is relatively complicated to calculate, and does not consider the influence of the slab pressure and slab width on the sickle bend control. Patent (6) solves the problem of the L2 automatic control of the roughing mill sickle control technology, but for L1, there is still only one manual method, that is, the operator manually adjusts the horizontal roll gap inclination value based on the roll gap correction amount automatically controlled by the rolling line L2, the plate shape visually monitored by the video, or the slab centerline deviation data fed back by the instrument side width meter, so as to achieve the purpose of adjusting the sickle at the mill exit.

[0013] At present, there are three heating furnaces in the 1580 production line in the steel plant. Each furnace type and the distance from the rolling line are different, resulting in different temperatures of the slabs drawn out of each furnace. After rough rolling, they present different sickle bends. For example, the slabs from the 1# furnace are bent in the working side direction, the 2# furnace is bent in the transmission side direction, and the 3# furnace may be bent in the working side direction. For this reason, the operator needs to frequently operate the handle to correct the amount of downward tilt, so as to control the amplitude of the sickle bend and ensure the finished coil shape. Since the 1580 production line has implemented the "1+N" operation station streamlining, a multi-post operator of N needs to take into account more operation points, and sometimes there is no time to adjust, resulting in frequent sickle bends or accidents.

[0014] When the 1580 production line adopted the sickle bend L1 fully automatic control mode, the above problems were improved to a certain extent. The full automation rate of this method can reach about 85%. However, the conditions for applying the sickle bend L1 fully automatic control mode are often affected by external factors. For example, the detection data of the width gauge is affected by the external descaling water vapor, and the detection data is easily distorted or discontinuous, which will lead to the inability to perform full automation; in addition, there are also cases such as inaccurate model learning calculations. Summary of the invention

[0015] In view of the defects existing in the prior art, the purpose of the present invention is to provide a method for semi-automatic adjustment of the preset control value of L1 to improve the sickle bend deviation of the strip, and to manually perform semi-automatic control of the sickle bend of each pass based on the number of rolling passes of the roughing mill, filling the gap that cannot be put into full automation, so as to avoid the operator being forced to choose the manual method, and improve the labor efficiency and the control accuracy of the sickle bend.

[0016] To achieve the above object, the present invention adopts the following technical solutions:

[0017] A method for improving the L1 semi-automatic adjustment of the preset control value for the strip camber deviation:

[0018] The width centerline deviation value of the slab rolled out by the roughing mill is detected by a width gauge, and the width centerline deviation value is uploaded to the L1 system. The L1 system then displays the width centerline deviation value on the HMI. The staff inputs the set value of the inclination value of each pass of the roughing mill on the HMI based on the width centerline deviation value displayed on the HMI to perform the semi-automatic control process of sickle bending.

[0019] Preferably, the semi-automatic control process of sickle bending specifically includes the following steps:

[0020] S1. The staff sets the tilt value setting value according to the rolling pass through the curve formed by the width centerline deviation value displayed on the HMI;

[0021] S2, preset the inclination value of the roll gap at the beginning of the current pass;

[0022] S3, determining whether the execution time of step S2 exceeds the set time, if so, displaying an alarm on the HMI, if not, proceeding to step S4;

[0023] S4, the working side of the rough rolling mill executes the preset roll gap inclination value;

[0024] S5. The rough rolling mill starts steel rolling.

[0025] Preferably, the semi-automatic control process of sickle bending also includes:

[0026] S6, judging whether the steel type and specification of the subsequent slab have changed, if so, exiting the sickle bending semi-automatic control process and entering the sickle bending fully automatic control process, if not, entering step S7;

[0027] S7, the width gauge detects the width centerline deviation value of the slab rolled out by the rough rolling mill, and uploads the width centerline deviation value to the L1 system;

[0028] S8, the L1 system displays the width centerline deviation value on the HMI, and then executes step S1;

[0029] S9. Repeat steps S1 to S8.

[0030] Preferably, the time set in step S3 is 20 seconds.

[0031] The present invention provides a method for semi-automatically adjusting the preset control value of L1 to improve the strip camber deviation. The semi-automatic control of the camber of each pass is performed manually based on the number of rolling passes of the roughing mill. When the following two situations occur: the detection data of the width gauge is affected by the water vapor of the peripheral descaling, the detection data is easily distorted or discontinuous, which will cause the full automatic function to be unable to be executed; or the full automatic control effect is poor due to inaccurate model learning calculation, and the operator turns off the full automatic function. At this time, the present invention can well fill the gap that cannot be put into full automatic operation, so as to avoid the operator having to choose the manual method, and improve the labor efficiency and the control accuracy of the camber. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a flow chart of the method for semi-automatically adjusting the preset control value of L1 of the present invention;

[0033] Figure 2 It is a schematic diagram of the system architecture of the method for semi-automatically adjusting the preset control value of L1 of the present invention. DETAILED DESCRIPTION

[0034] In order to better understand the above technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0035] Combination Figure 1 and Figure 2 As shown, the present invention provides a method for semi-automatically adjusting a preset control value of L1 for improving the camber deviation of a steel strip:

[0036] The width centerline deviation value of the slab rolled out by the roughing mill is detected by the width gauge 1 (installed behind the roughing mill), and the width centerline deviation value is uploaded to the L1 system 2 (basic automation system). The L1 system 2 then displays the width centerline deviation value on the HMI3 (human-machine interface), and the part exceeding the standard is marked in red. The staff uses the width centerline deviation value displayed on the HMI3 to input the set value of the inclination value of each pass of the roughing mill on the HMI to perform the semi-automatic control process of the sickle bend.

[0037] Add an input mode screen for the tilt value setting value in HMI3 of L1 system 2. If AUTO is selected in the screen, the L2 ALL function can be used. The tilt value setting values ​​of the three passes are all sent by the L2 system (process calculation system) for setting, which is the sickle bend L1 full-automatic control. You can also select AUTO in the screen to use the L1 ALL function, which is the sickle bend L1 semi-automatic control. If the operator needs to directly adjust the tilt amount manually, the mode will automatically switch from AUTO to MAN (full manual mode).

[0038] Add an input mode screen for the tilt value setting value in HMI3 of L1 system 2, that is, add one column of data input value, two columns of data display value and two columns of status display in the L1 system 2 pass plan screen. They correspond to the input and display of the tilt values ​​for three passes of the R1 rolling mill (usually three passes of R1 rolling). The first column is the tilt value setting data issued by the L2 system; the second column is the tilt value setting value that can be manually input by the staff through the current screen of the HMI; the third column is the Ref data column showing the tilt value data finally selected by the L1 system; the other two columns show whether the data of the current pass comes from the L2 system or the L1 system.

[0039] The semi-automatic control process of sickle bending specifically includes the following steps:

[0040] S1. The staff sets the tilt value according to the rolling pass through the curve formed by the width centerline deviation value displayed on HMI3;

[0041] S2: The tilt value of the roll gap is preset at the beginning of the current pass, the electromagnetic clutch is turned on, the clutch between the high-speed pressing and the low-speed pressing on the transmission side is disengaged, the clutch between the high-speed pressing and the low-speed pressing on the working side is connected, and the working side pressing mechanism uses the low-speed pressing motor to execute the tilt value setting;

[0042] S3, determine whether the execution time of step S2 exceeds the set time (20 seconds), if so, an alarm is displayed on the HMI, and the staff manually intervenes, if not, proceed to step S4;

[0043] S4, the electromagnetic clutch is closed, the pneumatic clutches on both sides are opened, the low-speed pressing motor is disengaged, and the two high-speed pressing motors on both sides of the working side of the rough rolling mill are used to execute the preset tilt value of the rear roll gap;

[0044] S5. The rough rolling mill starts feeding steel for rolling.

[0045] The semi-automatic control process of sickle bending also includes:

[0046] S6, judging whether the steel type and specification of the subsequent slab have changed, if so, exiting the sickle bending semi-automatic control process and entering the sickle bending fully automatic control process, if not, entering step S7;

[0047] S7, the width measuring instrument 1 detects the width centerline deviation value of the slab rolled out by the rough rolling mill, and uploads the width centerline deviation value to the L1 system 2;

[0048] S8, L1 system 2 displays the width centerline deviation value on HMI3, and then executes step S1;

[0049] S9. Repeat steps S1 to S8.

[0050] The L1 semi-automatic adjustment of preset control value method of the present invention is also indispensable as a supplement to the L2 system full-automatic control method on the 1580 production line, because the conditions for applying full-automatic are often affected by more peripheral factors: for example, the detection data of the width gauge is affected by the water vapor of the peripheral descaling, and the detection data is easily distorted or discontinuous, which will cause the full-automatic execution to be unable to be performed; in addition, there are also situations such as inaccurate model learning calculations. Therefore, it is indeed a good idea to use the L1 semi-automatic adjustment of preset control value method of the present invention to use the operator's experience to accurately adjust the control value of each pass of the relevant rolling mill. Moreover, once the set value of each pass is manually input, the subsequent plan is for slabs of the same steel grade and specification. Within the allowable deviation range, the operator does not need to manually input the adjustment set value for each piece of steel.

[0051] When the L1 semi-automatic adjustment method of the preset control value of the present invention is adopted, the automatic control rate (full automatic + semi-automatic) is increased to 99%, further improving the labor efficiency of the operator.

[0052] The following table compares the monthly average values ​​of the maximum value of the centerline deviation of the width of the third pass of R2 before and after the implementation of the present invention:

[0053]

[0054] It can be seen from the above table that after adopting the present invention, the maximum value of the centerline deviation of the width of the third pass of R2 outlet is significantly reduced, and the sickle bending plate shape control of R2 outlet is greatly improved, effectively preventing the large sickle bending phenomenon and accidents.

[0055] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. As long as they are within the spirit of the present invention, any changes or modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. A method for semi-automatically adjusting a preset control value of L1 to improve the camber deviation of a strip steel, characterized in that: The width centerline deviation value of the slab rolled out by the roughing mill is detected by a width gauge, and the width centerline deviation value is uploaded to the L1 system. The L1 system then displays the width centerline deviation value on the HMI. The staff inputs the set value of the inclination value of each pass of the roughing mill on the HMI based on the width centerline deviation value displayed on the HMI to perform the semi-automatic control process of sickle bending.

2. The method for semi-automatically adjusting the preset control value of L1 to improve the camber deviation of the strip steel according to claim 1 is characterized in that: The semi-automatic control process of sickle bending specifically includes the following steps: S1. The staff sets the tilt value setting value according to the rolling pass through the curve formed by the width centerline deviation value displayed on the HMI; S2, preset the inclination value of the roll gap at the beginning of the current pass; S3, determining whether the execution time of step S2 exceeds the set time, if so, displaying an alarm on the HMI, if not, proceeding to step S4; S4, the working side of the rough rolling mill executes the preset roll gap inclination value; S5. The rough rolling mill starts steel rolling.

3. The method for semi-automatically adjusting the preset control value of L1 for improving the camber deviation of the strip steel according to claim 2 is characterized in that: The semi-automatic control process of sickle bending also includes: S6, judging whether the steel type and specification of the subsequent slab have changed, if so, exiting the sickle bending semi-automatic control process and entering the sickle bending fully automatic control process, if not, entering step S7; S7, the width gauge detects the width centerline deviation value of the slab rolled out by the rough rolling mill, and uploads the width centerline deviation value to the L1 system; S8, the L1 system displays the width centerline deviation value on the HMI, and then executes step S1; S9. Repeat steps S1 to S8.

4. The method for semi-automatically adjusting the preset control value of L1 to improve the camber deviation of the strip steel according to claim 1, characterized in that: The time in step S3 is set to 20 seconds.

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