CN112007958A - Automatic control method for rough rolling camber - Google Patents
Automatic control method for rough rolling camber Download PDFInfo
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- CN112007958A CN112007958A CN202010810245.6A CN202010810245A CN112007958A CN 112007958 A CN112007958 A CN 112007958A CN 202010810245 A CN202010810245 A CN 202010810245A CN 112007958 A CN112007958 A CN 112007958A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/28—Control of flatness or profile during rolling of strip, sheets or plates
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Abstract
The invention discloses an automatic control method of rough rolling camber, which comprises the following steps: the first-pass strip steel enters a rolling mill to finish rough rolling, data acquisition is carried out on the first-pass strip steel rough rolling process and is fed back to a server, and the server detects the strip steel curvature and sends the strip steel curvature to a PCS system; the PCS system sends a first set compensation value to the PLC system through the curvature to control the position of the roll gap of the vertical roll of the rolling mill; the second pass of strip steel enters the rolling mill, and the server rolls according to the position of the tracked strip steel and a second set compensation value issued by the PCS system; when the roll gap is rolled until the vertical roll is contacted with at least one side of the second-pass strip steel, generating rolling force, and when the rolling force exceeds a set pressure value, switching the position control of the vertical roll to pressure control; the vertical roll is used as an actuating mechanism, and the pressure sum of the two sides of the operation and transmission is controlled to be a set pressure value of 1000 kN; when the tail part of the second pass strip steel leaves the vertical roll, the pressure control is switched to the reset position for control, and the vertical roll is reset.
Description
Technical Field
The invention relates to the technical field of steel-making production, in particular to an automatic control method of a rough rolling camber.
Background
The camber refers to the maximum distance between the side edges of the steel plate and the steel strip and a straight line connecting two end points of the measuring part, namely the deviation between the edge of one side of the steel strip and the straight line. The camber is generated once in the rough rolling stage, so that production accidents such as difficult threading, deviation and steel piling even occur in the subsequent finish rolling stage, the quality of a product and the production stability are seriously influenced, and aiming at the camber problem, a 2250 production line has no detection means at present, only operators can observe the bending degree of strip steel through cameras, then the horizontal roll gap of the rolling mill is manually adjusted, the accuracy depends on the experience of the operators, the camber and the roll gap leveling value do not form a certain quantitative relation, equipment of various large steel mills are inconsistent, and a control method of the camber also has a certain difference.
Under the general condition, camber control mainly relies on operating personnel manual adjustment roughing working roll both sides roll gap difference to realize, because rolling speed is fast, and manual adjustment is undulant big, the high section requirement of steel grade, camber is difficult to control.
At present, the rough rolling control camber can only be controlled by a horizontal roll gap leveling system, and the rough roll gap leveling system is composed of hydraulic leveling and mechanical pressing leveling. In the normal production process, an operator can manually intervene to adjust the roll gap of the horizontal roll so as to ensure good plate shape. The whole adjusting process is generally in a hydraulic adjusting plate shape, and if the hydraulic adjusting plate cannot meet the requirement, mechanical pressing is used for leveling. The action range of the leveling single side of the horizontal roller of the rolling mill is +/-5 mm, when the adjusting stroke is larger than +/-5 mm, the mechanical pressing operation linkage is not satisfied, and the roller gap cannot be set at the moment, so that the rolling line stops rolling. Therefore, a technology for automatically detecting and controlling the camber is needed.
Disclosure of Invention
The invention aims to provide an automatic control method for rough-rolling sickle curves, which can automatically adjust the standard state of the steel strips of the sickle curves.
In order to achieve the purpose, the invention provides the following technical scheme:
the invention provides an automatic control method of rough rolling camber, which comprises the following steps:
s1, enabling the first-pass strip steel to enter a rolling mill to finish rough rolling, collecting data in the rough rolling process of the first-pass strip steel through a camera of the detection device, feeding the data back to a server, establishing a model by the server to realize detection of the strip steel curvature, detecting the strip steel curvature and sending the detected strip steel curvature to a PCS system; the first pass of strip steel is used as initial comparison data, so that the strip steel of the second pass and later is automatically adjusted.
And S2, the PCS system sends a first set compensation value to the PLC system for control through the bending degree of the strip steel, and the PLC system controls the position of the roll gap clearance of the vertical roll of the rolling mill after the head of the strip steel of the second pass exceeds the position of the vertical roll by a first safety distance.
And S3, when the second pass of strip steel enters the rolling mill, the server calculates the position of the tracked strip steel according to the speed of the working rolls and the forward sliding value of the PCS system, and when the tracking calculation distance of the head of the second pass of strip steel exceeds the position of the vertical rolls and the signals of the hot metal detector beside the vertical rolls are triggered, the roll gap of the vertical rolls performs rolling according to a second set compensation value sent by the PCS system.
And S4, generating rolling force after the roll gap rolling is carried out until the vertical roll is contacted with at least one side of the second-pass strip steel, and switching the position control of the vertical roll to pressure control after the rolling force exceeds a set pressure value.
And S5, in the pressure control mode, the vertical roller is used as an actuating mechanism, and the sum of the pressures on the two sides of the operation and transmission is controlled to be a set pressure value of 1000 kN.
And S6, when the tail of the second pass of strip steel leaves the vertical roll and the tail of the second pass of strip steel approaches to the vertical roll by a second safety distance, the vertical roll is switched to the position control by pressure control, and the vertical roll is reset.
Further, the step of detecting the bending degree of the strip steel by the server in the step S1 includes:
s11, defining the head length of the strip steel as xTail and the tail length of the strip steel as xHead at initial values so that the distance between the head length and the tail of the strip steel is 10 percent of the length L of the strip steel,
s12, for a given xhead and xtail:
a. quadratic fit raw data from xtail < x < xhead;
b. linear regression through the raw data from 0< x < xtail and xhead < x < L, with xtail and xhead assigned to the middle to form a continuous curve;
s13, changing xhead and xtail by changing xhead and xtail to minimize the root mean square deviation between the fit data and the original data;
s14, reading approximate values of the head curve, the tail curve and the middle curve of the strip steel;
and S15, storing the approximate value of each reading in the database.
Further, the calculation formula of the first set compensation value and the roll gap in step S2 is as follows: GAP = W plate + offset "X" mm;
in the formula, GAP is a roll GAP; wBoardThe width of the slab; the compensation quantity X mm is a set compensation value of the vertical roller before loading.
Further, the first safety distance in the step S2 is 2m from the head of the strip to the middle of the vertical roll.
Further, in step S3, the roll gap is rolled according to a second set compensation value issued by the PCS system, and a calculation formula of the roll gap is as follows:
GAP = W plate + offset "Y" mm;
in the formula, GAP is a roll GAP; wBoardThe width of the slab; the compensation quantity Y mm is a set compensation value of the vertical roller after being loaded.
Further, in the step S5, the sum of the pressures at the two sides of the operation and transmission is controlled, the amplitude limiting value of the roll gap in the control process is less than or equal to 8mm, and when the rolling mill stops and gives an alarm when the rolling mill stops for more than 8 mm. The problem of edge quality of the strip steel caused by large bending degree and too much straightening compensation of the strip steel is solved.
Further, the second safety distance of the step S6 is 1m from the tail of the strip steel to the middle of the horizontal roll.
In conclusion, the beneficial effects of the invention are as follows:
the bending degree of the first pass of strip steel is detected through a detection device of the rolling mill, and the server dynamically feeds back and adjusts the roll gap clearance of the horizontal roll and the vertical roll of the roughing mill according to the collected historical data so as to achieve the effect of automatically controlling and adjusting the camber of the second pass of strip steel and the subsequent passes of strip steel.
The advantageous effects of the additional features of the present invention will be explained in the detailed description of the invention
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a logic flow diagram of the method of the present invention for automatically controlling the roughing camber;
FIG. 2 is a graph of initial values of xhead and xtail given in step 12 of the embodiment of the present invention;
FIG. 3 is a graph of the quadratic fit to the xtail < x < xhead portion in step a according to an embodiment of the present invention;
FIG. 4 is a continuous graph of linear regression and middle distribution of the head and tail raw data in step b according to the embodiment of the present invention;
FIG. 5 is a graph of step 13 to minimize the RMS deviation change between fit data and raw data xtail and xhead in an embodiment of the present invention;
FIG. 6 is a graph of the approximate values of the leading curve, the trailing curve, and the middle curve read at step 14 in an embodiment of the present invention;
FIG. 7 is a graph of an approximation of the optimization of step S15 for each reading in an embodiment of the present invention;
FIG. 8 is a schematic diagram illustrating the location of the first safety distance of step S2 in the embodiment of the present invention;
fig. 9 is a schematic position diagram of the second safety distance of step S6 in the embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.
Referring to fig. 1, the invention provides an automatic control method of rough rolling camber, step S1, the first pass of strip steel enters the rolling mill to finish rough rolling, the data acquisition is carried out on the first pass of strip steel rough rolling process by the camera of the detection device, and the data is fed back to the server, the server establishes model processing to realize the detection of the strip steel curvature, and the detected strip steel curvature is sent to the PCS system; the first pass of strip steel is used as initial comparison data, so that the strip steel of the second pass and later is automatically adjusted.
The step of detecting the bending degree of the strip steel by the server in the step S1 includes:
step S11, defining the initial strip steel head length xTail and strip steel tail length xHead to make their distance to the head or tail 10% of the strip steel length L,
as shown in connection with FIG. 2, step S12, for a given initial value of xhead and xtail:
referring to FIG. 3, a, quadratic fit is performed on the raw data from xtail < x < xhead;
b, linear regression through the raw data from 0< x < xtail and xhead < x < L, with the xtail and xhead assigned to the middle part to form a continuous curve, as shown in fig. 4;
step S13, shown in connection with FIG. 5, alters xhead and xtail by altering xhead and xtail to minimize the root mean square deviation between the fit data and the original data;
referring to fig. 6, step S14 is to read approximate values of the strip steel head curve, tail curve and middle curve;
referring to fig. 7, in step S15, the approximate value read each time is stored in the database, so as to update the data of the server detection system and improve the accuracy of control.
Referring to fig. 8, in step S2, the PCS system sends a first set compensation value to the PLC system for control through the strip bending degree, and after the head of the strip of the second pass exceeds the position of the vertical roll by a first safety distance, the PLC system controls the position of the roll gap of the vertical roll of the rolling mill to a position where contact with the strip is avoided. Preferably, the first safety distance in the step S2 is 2m from the head of the strip to the middle of the vertical roll, so that the strip in the second pass is prevented from striking the vertical roll due to abnormal threading.
The calculation formula of the first set compensation value and the roll gap in the step S2 is as follows: GAP = W plate + offset "X" mm;
in the formula, GAP is a roll GAP; wBoardThe width of the slab; the compensation quantity X mm is a set compensation value of the vertical roller before loading.
And step S3, when the second pass of strip steel enters the rolling mill, the server calculates the position of the tracked strip steel according to the speed of the working rolls and the forward sliding value of the PCS system, and when the tracking calculation distance of the head of the second pass of strip steel exceeds the position of the vertical rolls and the signals of the hot metal detector beside the vertical rolls are triggered, the roll gap of the vertical rolls perform rolling according to a second set compensation value issued by the PCS system. Preferably, the roll gap performs rolling according to a second set compensation value issued by the PCS system, and a calculation formula of the roll gap is as follows:
GAP = W plate + offset "Y" mm;
in the formula, GAP is a roll GAP; wBoardThe width of the slab; the compensation quantity Y mm is a set compensation value of the vertical roller after being loaded.
And step S4, when the roll gap rolling is carried out until the vertical roll contacts at least one side of the second-pass strip steel, the rolling force is generated, and the rolling force exceeds a set pressure value, the position control of the vertical roll is switched to pressure control.
And step S5, in a pressure control mode, the vertical roller is used as an actuating mechanism, the pressure sum of the two sides of the operation and transmission is controlled to be a set pressure value of 1000kN, preferably, the amplitude limiting value of the roll gap in the control process is less than or equal to 8mm, and when the rolling mill stops and gives an alarm when the rolling mill stops for more than 8 mm. The problem of edge quality of the strip steel caused by large bending degree and too much straightening compensation of the strip steel is solved.
Referring to fig. 9, in step S6, when the tail of the second pass strip leaves the vertical rolls and the tail of the second pass strip approaches the vertical rolls by the second safety distance, the vertical rolls are switched to the position control by the pressure control, and the vertical rolls are reset. Preferably, the second safety distance in step S6 is 1m from the tail of the strip to the middle of the horizontal roll, so as to avoid the strip of the second pass from hitting the vertical roll due to abnormal threading.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (7)
1. An automatic control method for rough rolling camber is characterized by comprising the following steps:
s1, the first-pass band steel enters a rolling mill to finish rough rolling, data acquisition is carried out on the first-pass band steel rough rolling process through a detection device, the data are fed back to a server, the server detects the band steel curvature and sends the band steel curvature to a PCS system;
s2, the PCS system sends a first set compensation value to the PLC system through the bending degree of the strip steel for control, and the PLC system controls the position of the roll gap clearance of the vertical roll of the rolling mill after the head of the strip steel of the second pass exceeds the position of the vertical roll by a first safety distance;
s3, when the second pass of strip steel enters the rolling mill, the server calculates the position of the tracked strip steel according to the speed of the working rolls and the forward sliding value of the PCS system, and when the tracking calculation distance of the head of the second pass of strip steel exceeds the position of the vertical rolls and the signals of the hot metal detector beside the vertical rolls are triggered, the roll gap of the vertical rolls performs rolling according to a second set compensation value issued by the PCS system;
s4, when the roll gap is rolled until the vertical roll contacts at least one side of the second-pass strip steel, rolling force is generated, and after the rolling force exceeds a set pressure value, the position control of the vertical roll is switched to pressure control;
s5, in a pressure control mode, the vertical roller is used as an actuating mechanism, and the pressure sum of the two sides of the operation and transmission is controlled to be a set pressure value of 1000 kN;
and S6, when the tail of the second pass of strip steel leaves the vertical roll and the tail of the second pass of strip steel is close to the horizontal roll by a second safety distance, switching the vertical roll back to position control by pressure control, and resetting the vertical roll.
2. The automatic control method for the rough rolling camber according to claim 1, wherein the step of detecting the bending degree of the strip steel by the server in the step S1 comprises:
s11, defining the head length of the strip steel as xTail and the tail length of the strip steel as xHead at initial values so that the distance between the head length and the tail of the strip steel is 10 percent of the length L of the strip steel,
s12, for a given xhead and xtail:
a. quadratic fit raw data from xtail < x < xhead;
b. linear regression through the raw data from 0< x < xtail and xhead < x < L, with xtail and xhead assigned to the middle to form a continuous curve;
s13, changing xhead and xtail by changing xhead and xtail to minimize the root mean square deviation between the fit data and the original data;
s14, reading approximate values of the head curve, the tail curve and the middle curve of the strip steel;
and S15, storing the approximate value of each reading in the database.
3. The automatic control method for rough rolling camber according to claim 1, wherein the calculation formula of the first set compensation value and the roll gap clearance in S2 is as follows: GAP = W plate + offset "X" mm;
in the formula, GAP is a roll GAP; wBoardThe width of the slab; the compensation quantity X mm is a set compensation value of the vertical roller before loading.
4. The automatic control method for rough rolling camber according to claim 3, wherein the first safety distance in S2 is 2m from the head of the strip to the middle of the vertical roll.
5. The automatic control method for rough rolling camber according to claim 4, wherein in S3, the roll gap is calculated according to a second set compensation value issued by the PCS system, and the roll gap is calculated according to the following formula:
GAP = W plate + offset "Y" mm;
in the formula, GAP is a roll GAP; wBoardThe width of the slab; the compensation quantity Y mm is a set compensation value of the vertical roller after being loaded.
6. The automatic control method for rough rolling camber according to claim 5, wherein in S5, the pressure sum at both sides of the operation and transmission is controlled, the amplitude limiting value of the roll gap in the control process is less than or equal to 8mm, and when the rolling mill stops and gives an alarm when the rolling mill stops for more than 8 mm.
7. The automatic control method for the rough rolling camber according to claim 6, wherein the second safety distance of S6 is 1m from the tail of the strip to the middle of the horizontal roll.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112742867A (en) * | 2021-01-30 | 2021-05-04 | 宝钢湛江钢铁有限公司 | Method for normal rolling after SSP pinch roll slipping |
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