CN112517644A - Silicon steel W600 thickness control operation method - Google Patents
Silicon steel W600 thickness control operation method Download PDFInfo
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- CN112517644A CN112517644A CN202011194124.XA CN202011194124A CN112517644A CN 112517644 A CN112517644 A CN 112517644A CN 202011194124 A CN202011194124 A CN 202011194124A CN 112517644 A CN112517644 A CN 112517644A
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- thickness
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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
- B21B37/16—Control of thickness, width, diameter or other transverse dimensions
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Abstract
The invention discloses a silicon steel W600 thickness control operation method, relates to the field of steel thickness control operation, and comprises the step of respectively and independently adjusting roll gap values of two side parts in the width direction of strip steel so as to control the thickness of a strip steel outlet. According to the invention, after the first strip steel head is rolled out to obtain F7, the thickness is changed to 2.8MM after the F7AGC is closed, and the thickness of the rolled strip steel head cannot be hit, so that the thickness is hit by manually clicking the lower F7 press roll gap at the first time, and the manual joint control with the speed is needed to be in place, the tension is ensured to be constant and larger while the press roll gap is kept, the plate shape is ensured to be stable, and the thickness is hit under the action of the press roll gap and the acceleration; after the operation method is used, the thickness of the high-grade silicon steel W600 is effectively controlled, the influence on the planned hit rate and the internal loss caused by the thickness change of the first piece is reduced, the quality of a workshop is guaranteed, the production cost of an enterprise is reduced, and a solid foundation is laid for improving the image of the enterprise and improving the market competitiveness.
Description
Technical Field
The invention relates to the field of steel thickness control operation, in particular to a silicon steel W600 thickness control operation method.
Background
In the process of rolling a medium-thickness steel plate, a thickness Control system usually uses AGC (Automatic Gauge Control) as a core technology, which takes the thickness of a rolled steel plate as a target quantity, takes rolling parameters such as rolling force, incoming material thickness, rolling speed and the like as limiting quantities, takes a roll Gap and a steel plate transmission speed as regulating quantities, calculates the outlet thickness of the steel plate through a roll Gap actual measurement value and a rolling mill force actual measurement value according to a rolling mill bounce equation by using the AGC technology, and when the calculated outlet thickness does not accord with the set outlet thickness, changes the rolling roll gaps on two sides of the steel plate through HGC (Hydraulic Gap Control) oil cylinders by using the AGC technology to ensure that the rolling thickness is the same as the set thickness; the adjustment is carried out in real time and on line, and the roll gap adjustment is required according to the deviation between the measured rolling force and the set rolling force.
In the process of rolling the plate strip, one of the most common thickness control methods is to measure the actual thickness of the strip steel by a rack outlet thickness gauge and then perform feedback control on the thickness by adjusting a hydraulic roll gap of a rolling mill; due to the structural limitations of the rolling mill, the maintenance of the thickness gauge, and the damage to the gauge by strip breakage, the thickness gauge is generally installed at a position far from the roll gap where the thickness variation is directly generated, for example, the outlet thickness gauge of the hot continuous rolling mill is installed at a distance of about 2000 to 4000mm from the center line of the work roll.
In the existing silicon steel W600 thickness control operation method, in the current production, when the first silicon steel W600 is rolled, because the hardness of steel grades is different and the setting is inaccurate, phase change is generated among racks and the like, strip steel is unstably threaded in a finishing mill, the threading speed is too fast, and the plate type change in the mill is larger; the width is easily affected by head crushing and the upper wall of strip steel, particularly, the width of silicon steel with high silicon content such as W600 and the like is affected, so that the first rolled block is changed in thickness by 2.8mm to transit and the AGC of an F7 rack is closed under the normal condition, the improvement of the planned hit rate and the internal loss of quality are directly affected, the first thickness control operation method of the silicon steel W600 is obtained through summarization, and the problems that the planned hit rate and the internal loss are affected due to the fact that the thickness is not hit can be effectively solved through verifying the operation method.
Disclosure of Invention
The invention aims to: the silicon steel W600 thickness control operation method aims at solving the problems that strip steel cannot be stably threaded in a finishing mill, the threading speed is too high, the change of the plate type of the mill is large, the head is easily crushed and the width of the strip steel is influenced by the upper wall of the strip steel due to different hardness and inaccurate setting of steel grades and phase change between racks.
In order to achieve the purpose, the invention provides the following technical scheme: the silicon steel W600 thickness control operation method comprises the steps of respectively and independently adjusting roll gap values of two side portions in the width direction of strip steel so as to control the thickness of a strip steel outlet, and comprises the following steps:
the method comprises the following steps: acquiring equipment parameters of a rolling mill and specification parameters of strip steel;
the parameters of the rolling mill equipment comprise: the method comprises the following steps of (1) rolling speed, the distance between an X-ray thickness gauge and the center line of a final stand, the response time of the thickness gauge, the actual roll diameter of a working roll, the original roll diameter of the working roll, the actual roll diameter of a supporting roll, the original roll diameter of the supporting roll, the convexity of the working roll and the convexity of the supporting roll;
step two: the specification parameters of the strip steel comprise: rolling steel type, incoming material thickness and finished product thickness;
step three: performing unit step response test on the last frame rolling mill, and determining a unit step response period, namely a time parameter of a hydraulic cylinder transfer function, a control period of a monitoring AGC system and the number of unit step response lag sampling discrete points;
step four: controlling the last stand rolling mill by adopting a Smith pre-estimation control strategy of a proportional-integral controller with an inertia link;
step five: utilizing a hot continuous rolling finish rolling monitoring AGC system control model, and carrying out thickness control in the next period by adjusting a hydraulic cylinder;
step six: the hot continuous rolling finish rolling monitoring AGC system control model is used for determining the roll gap regulating quantity of the next period by adopting a GM mode;
step seven: obtaining a primary roll seam adjusting value S
Correcting S according to thickness fluctuation of two sides in the width direction of the strip steel, wherein the two sides in the width direction of the strip steel are respectively a transmission side and an operation side, and the thickness fluctuation comprises the amplitude of the thickness fluctuation and the frequency of the thickness fluctuation: if at least one of the amplitude and the frequency of the thickness fluctuation exceeds a threshold value, correcting the original roll gap adjusting value S of the side to obtain a corrected roll gap adjusting value S1 and/or S2 of the transmission side and/or the operation side, and then issuing; if the frequency and the amplitude of the thickness fluctuation do not exceed the threshold value, the original roll gap adjusting value on the side is not corrected and is directly issued;
step eight: and respectively and independently adjusting the roll gap values on the two sides in the width direction of the strip steel according to the issued roll gap adjusting values on the two sides so as to control the thickness of the strip steel outlet.
Step nine: after the first strip steel head is rolled out from F7, the thickness is changed to 2.8MM after the F7AGC is closed, and the thickness of the rolled strip steel head cannot be hit, so that the thickness can be hit by manually clicking the lower F7 roll seam in the first time, and the manual joint control with the speed is needed to be in place, so that the tension is constant and large while the roll seam is pressed, and the stability of the plate type is ensured.
Preferably, the threshold value for the amplitude of the thickness fluctuation is 2% of the thickness of the rolled strip.
Preferably, the threshold value corresponding to the frequency of the thickness fluctuation is: there were 2 periods of fluctuation within one work roll circumference.
Preferably, the AGC system control model for monitoring the finish rolling of the hot continuous rolling is used for determining the roll gap regulating quantity of the next period by adopting a GM mode.
Preferably, the AGC system control model for monitoring the finish rolling of the hot continuous rolling is obtained according to the following steps: step 4.1: and the X-ray thickness gauge carries out multipoint sampling on the thickness deviation measured value in each control period and determines the average thickness deviation of the plate strip sample at the moment i.
Preferably, the X-ray thickness gauge performs multipoint sampling on the thickness deviation measured value in each control period, and determines the average thickness deviation of the plate strip sample at the moment i.
Preferably, the pressure sensor carries out multipoint sampling on the actual operating side pressure value and the actual transmission side pressure value in each control period, and determines the average pressure value of the plate belt sample at the moment i.
Preferably, the thickness deviation caused by the bounce of the rolling mill and the thickness deviation caused by the deflection of a roll system are calculated, the oil film thickness compensation quantity, the roll thermal expansion compensation quantity and the roll abrasion compensation quantity sent by a process computer are received, and after zero drift correction, the soft measurement thickness deviation of the plate strip is obtained by adopting a GM mode.
Compared with the prior art, the invention has the beneficial effects that: after the first strip steel head is rolled out from F7, the thickness is changed to 2.8MM after the F7AGC is closed, and the thickness of the rolled strip steel head cannot be hit, so that the thickness is hit by manually clicking the lower F7 press roll gap at the first time, and the manual joint control with the speed is needed to be in place, the tension is ensured to be constant and larger while the press roll gap is ensured, the plate shape is ensured to be stable, and the thickness is hit under the action of the press roll gap and the acceleration; after the operation method is used, the thickness of the high-grade silicon steel W600 is effectively controlled, the influence on the planned hit rate and the internal loss caused by the thickness change of the first piece is reduced, the quality of a workshop is guaranteed, the production cost of an enterprise is reduced, and a solid foundation is laid for improving the image of the enterprise and improving the market competitiveness.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the illustrated orientations or positional relationships, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "disposed" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. The following describes an embodiment of the present invention based on its overall structure.
The first embodiment is as follows:
the invention provides a technical scheme that: the operation method for controlling the thickness of the silicon steel W600 and the operation method for controlling the thickness of the silicon steel W600 comprise the steps of respectively and independently adjusting roll gap values of two side parts in the width direction of strip steel so as to control the thickness of an outlet of the strip steel, wherein the operation method for controlling the thickness comprises the following steps:
the method comprises the following steps: acquiring equipment parameters of a rolling mill and specification parameters of strip steel;
the parameters of the rolling mill equipment comprise: the method comprises the following steps of (1) rolling speed, the distance between an X-ray thickness gauge and the center line of a final stand, the response time of the thickness gauge, the actual roll diameter of a working roll, the original roll diameter of the working roll, the actual roll diameter of a supporting roll, the original roll diameter of the supporting roll, the convexity of the working roll and the convexity of the supporting roll;
step two: the specification parameters of the strip steel comprise: rolling steel type, incoming material thickness and finished product thickness;
step three: performing unit step response test on the last frame rolling mill, and determining a unit step response period, namely a time parameter of a hydraulic cylinder transfer function, a control period of a monitoring AGC system and the number of unit step response lag sampling discrete points;
step four: controlling the last stand rolling mill by adopting a Smith pre-estimation control strategy of a proportional-integral controller with an inertia link;
step five: utilizing a hot continuous rolling finish rolling monitoring AGC system control model, and carrying out thickness control in the next period by adjusting a hydraulic cylinder;
step six: the hot continuous rolling finish rolling monitoring AGC system control model is used for determining the roll gap regulating quantity of the next period by adopting a GM mode;
step seven: obtaining a primary roll seam adjusting value S
Correcting S according to thickness fluctuation of two sides in the width direction of the strip steel, wherein the two sides in the width direction of the strip steel are respectively a transmission side and an operation side, and the thickness fluctuation comprises the amplitude of the thickness fluctuation and the frequency of the thickness fluctuation: if at least one of the amplitude and the frequency of the thickness fluctuation exceeds a threshold value, correcting the original roll gap adjusting value S of the side to obtain a corrected roll gap adjusting value S1 and/or S2 of the transmission side and/or the operation side, and then issuing; if the frequency and the amplitude of the thickness fluctuation do not exceed the threshold value, the original roll gap adjusting value on the side is not corrected and is directly issued;
step eight: and respectively and independently adjusting the roll gap values on the two sides in the width direction of the strip steel according to the issued roll gap adjusting values on the two sides so as to control the thickness of the strip steel outlet.
Step nine: after the first strip steel head is rolled out from F7, the thickness is changed to 2.8MM after the F7AGC is closed, and the thickness of the rolled strip steel head cannot be hit, so that the thickness can be hit by manually clicking the lower F7 roll seam in the first time, and the manual joint control with the speed is needed to be in place, so that the tension is constant and large while the roll seam is pressed, and the stability of the plate type is ensured.
Further, the threshold value of the amplitude corresponding to the thickness fluctuation is 2% of the thickness of the rolled strip steel; the threshold for the frequency of the thickness fluctuation is: there were 2 periods of fluctuation within one work roll circumference.
Further, the AGC system control model for monitoring the hot continuous rolling finish rolling is used for determining the roll gap regulating quantity of the next period by adopting a GM mode; the control model of the hot continuous rolling finish rolling monitoring AGC system is obtained according to the following steps: step 4.1: and the X-ray thickness gauge carries out multipoint sampling on the thickness deviation measured value in each control period and determines the average thickness deviation of the plate strip sample at the moment i.
Further, the X-ray thickness gauge carries out multipoint sampling on the thickness deviation measured value in each control period, and determines the average thickness deviation of the plate strip sample at the moment i; and the pressure sensor carries out multi-point sampling on the actual value of the operating side pressure and the actual value of the transmission side pressure in each control period and determines the average pressure value of the plate belt sample at the moment i.
Further, the thickness deviation caused by the bouncing of the rolling mill and the thickness deviation caused by the deflection of a roller system are calculated, the oil film thickness compensation quantity, the roller thermal expansion compensation quantity and the roller abrasion compensation quantity sent by a process computer are received, and after zero drift correction, the soft measurement thickness deviation of the plate strip is obtained by adopting a GM mode.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Claims (8)
1. The silicon steel W600 thickness control operation method comprises the steps of respectively and independently adjusting roll gap values of two side portions in the width direction of strip steel so as to control the thickness of a strip steel outlet, and comprises the following steps:
the method comprises the following steps: acquiring equipment parameters of a rolling mill and specification parameters of strip steel;
the parameters of the rolling mill equipment comprise: the method comprises the following steps of (1) rolling speed, the distance between an X-ray thickness gauge and the center line of a final stand, the response time of the thickness gauge, the actual roll diameter of a working roll, the original roll diameter of the working roll, the actual roll diameter of a supporting roll, the original roll diameter of the supporting roll, the convexity of the working roll and the convexity of the supporting roll;
step two: the specification parameters of the strip steel comprise: rolling steel type, incoming material thickness and finished product thickness;
step three: performing unit step response test on the last frame rolling mill, and determining a unit step response period, namely a time parameter of a hydraulic cylinder transfer function, a control period of a monitoring AGC system and the number of unit step response lag sampling discrete points;
step four: controlling the last stand rolling mill by adopting a Smith pre-estimation control strategy of a proportional-integral controller with an inertia link;
step five: utilizing a hot continuous rolling finish rolling monitoring AGC system control model, and carrying out thickness control in the next period by adjusting a hydraulic cylinder;
step six: the hot continuous rolling finish rolling monitoring AGC system control model is used for determining the roll gap regulating quantity of the next period by adopting a GM mode;
step seven: obtaining a primary roll seam adjusting value S
Correcting S according to thickness fluctuation of two sides in the width direction of the strip steel, wherein the two sides in the width direction of the strip steel are respectively a transmission side and an operation side, and the thickness fluctuation comprises the amplitude of the thickness fluctuation and the frequency of the thickness fluctuation: if at least one of the amplitude and the frequency of the thickness fluctuation exceeds a threshold value, correcting the original roll gap adjusting value S of the side to obtain a corrected roll gap adjusting value S1 and/or S2 of the transmission side and/or the operation side, and then issuing; if the frequency and the amplitude of the thickness fluctuation do not exceed the threshold value, the original roll gap adjusting value on the side is not corrected and is directly issued;
step eight: and respectively and independently adjusting the roll gap values on the two sides in the width direction of the strip steel according to the issued roll gap adjusting values on the two sides so as to control the thickness of the strip steel outlet.
Step nine: after the first strip steel head is rolled out from F7, the thickness is changed to 2.8MM after the F7AGC is closed, and the thickness of the rolled strip steel head cannot be hit, so that the thickness can be hit by manually clicking the lower F7 roll seam in the first time, and the manual joint control with the speed is needed to be in place, so that the tension is constant and large while the roll seam is pressed, and the stability of the plate type is ensured.
2. The silicon steel W600 thickness control operation method of claim 1, wherein: the threshold value for the amplitude of the thickness fluctuation is 2% of the thickness of the rolled strip.
3. The silicon steel W600 thickness control operation method of claim 1, wherein: the threshold for the frequency of the thickness fluctuation is: there were 2 periods of fluctuation within one work roll circumference.
4. The silicon steel W600 thickness control operation method of claim 1, wherein: and the control model of the hot continuous rolling finish rolling monitoring AGC system is used for determining the roll gap regulating quantity of the next period by adopting a GM mode.
5. The silicon steel W600 thickness control operation method of claim 1, wherein: the control model of the hot continuous rolling finish rolling monitoring AGC system is obtained according to the following steps: step 4.1: and the X-ray thickness gauge carries out multipoint sampling on the thickness deviation measured value in each control period and determines the average thickness deviation of the plate strip sample at the moment i.
6. The silicon steel W600 thickness control operation method of claim 1, wherein: and the X-ray thickness gauge carries out multipoint sampling on the thickness deviation measured value in each control period and determines the average thickness deviation of the plate strip sample at the moment i.
7. The silicon steel W600 thickness control operation method of claim 1, wherein: and the pressure sensor carries out multi-point sampling on the actual value of the operating side pressure and the actual value of the transmission side pressure in each control period and determines the average pressure value of the plate belt sample at the moment i.
8. The silicon steel W600 thickness control operation method of claim 1, wherein: and calculating the thickness deviation caused by the bounce of the rolling mill and the thickness deviation caused by the deflection of a roll system, receiving the oil film thickness compensation quantity, the roll thermal expansion compensation quantity and the roll abrasion compensation quantity sent by the process computer, and obtaining the soft measurement thickness deviation of the plate strip by adopting a GM mode after correcting the zero drift.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011194124.XA CN112517644A (en) | 2020-10-30 | 2020-10-30 | Silicon steel W600 thickness control operation method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011194124.XA CN112517644A (en) | 2020-10-30 | 2020-10-30 | Silicon steel W600 thickness control operation method |
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| CN112517644A true CN112517644A (en) | 2021-03-19 |
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| CN202011194124.XA Withdrawn CN112517644A (en) | 2020-10-30 | 2020-10-30 | Silicon steel W600 thickness control operation method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114101338A (en) * | 2021-10-26 | 2022-03-01 | 中冶南方工程技术有限公司 | Cold-rolled silicon steel thickness control method and device based on full-flow data |
| CN114522985A (en) * | 2022-04-13 | 2022-05-24 | 东莞海裕百特智能装备有限公司 | Roller rolling control method, system and computer readable storage medium |
-
2020
- 2020-10-30 CN CN202011194124.XA patent/CN112517644A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114101338A (en) * | 2021-10-26 | 2022-03-01 | 中冶南方工程技术有限公司 | Cold-rolled silicon steel thickness control method and device based on full-flow data |
| CN114522985A (en) * | 2022-04-13 | 2022-05-24 | 东莞海裕百特智能装备有限公司 | Roller rolling control method, system and computer readable storage medium |
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Application publication date: 20210319 |