KR100448620B1 - Method for controlling thickness of strip at cold rolling mill - Google Patents

Method for controlling thickness of strip at cold rolling mill Download PDF

Info

Publication number
KR100448620B1
KR100448620B1 KR10-1999-0062132A KR19990062132A KR100448620B1 KR 100448620 B1 KR100448620 B1 KR 100448620B1 KR 19990062132 A KR19990062132 A KR 19990062132A KR 100448620 B1 KR100448620 B1 KR 100448620B1
Authority
KR
South Korea
Prior art keywords
thickness
coil
control method
line
cold rolling
Prior art date
Application number
KR10-1999-0062132A
Other languages
Korean (ko)
Other versions
KR20010064018A (en
Inventor
정석모
노호섭
조병용
정병화
Original Assignee
주식회사 포스코
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 주식회사 포스코 filed Critical 주식회사 포스코
Priority to KR10-1999-0062132A priority Critical patent/KR100448620B1/en
Publication of KR20010064018A publication Critical patent/KR20010064018A/en
Application granted granted Critical
Publication of KR100448620B1 publication Critical patent/KR100448620B1/en

Links

Classifications

    • 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
    • B21B37/18—Automatic gauge control
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
    • B21B1/24—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process
    • B21B1/28—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process by cold-rolling, e.g. Steckel cold mill
    • 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
    • B21B37/165—Control of thickness, width, diameter or other transverse dimensions responsive mainly to the measured thickness of the product
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B38/00—Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product
    • B21B38/04—Methods or devices for measuring, detecting or monitoring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product for measuring thickness, width, diameter or other transverse dimensions of the product
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B2261/00—Product parameters
    • B21B2261/02—Transverse dimensions
    • B21B2261/04—Thickness, gauge
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B2261/00—Product parameters
    • B21B2261/02—Transverse dimensions
    • B21B2261/06—Width
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B2271/00—Mill stand parameters
    • B21B2271/02—Roll gap, screw-down position, draft position

Abstract

본 발명은 연속 냉간 압연에서 코일과 코일의 연결부위가 밀(Mill)을 통과할 때 코일의 선단부(top) 및 후단부(tail)에서 수요가 요구 두께의 상/하한을 벗어나는 오프게이지의 길이를 감소시킬 수 있도록 된 냉간압연 주행간 판두께 변경구간에서의 두께제어방법에 관한 것이다.According to the present invention, the length of the off-gauge in which the demand falls outside the upper and lower limits of the required thickness at the top and tail of the coil when the coil and the coil connection portion pass through the mill in the continuous cold rolling. The present invention relates to a thickness control method in a section for changing a plate thickness between cold rolled driving, which can be reduced.

이를 위하여 본 발명은 연속 냉간 압연에서 코일과 코일의 연결부위가 밀을 통과할 때 코일의 선단부 및 후단부에서 발생되는 오프게이지의 길이를 감소시킬 수 있도록 된 냉간압연 주행간 판두께 변경구간에서의 두께제어방법에 있어서,To this end, the present invention is to reduce the length of the off-gauge generated in the leading and rear ends of the coil when passing through the mill in the cold rolling continuous rolling thickness change section In the thickness control method,

상기 선/후행코일의 두께, 폭, 강종데이터를 입력받아 각 데이터를 상호 비교하여 선/후행코일이 동일사이즈, 동일강종인 경우 일반용접부로 구분하고, 선/후행코일의 연결부위가 사이즈 및 강종이 다른 경우에는 각 경우에 따라서 3타입의 두께변경점으로 구분하여 선/후행코일의 연결부위에서의 오프게이지 발생을 감소시킬 수 있도록 한 것을 특징으로 한다.The thickness, width and steel grade data of the line / trailing coil are inputted, and the data are compared with each other.If the line / trailing coil is the same size and the same steel grade, the common welding part is used, and the connection portion of the line / trailing coil is size and steel grade. In this other case, it is possible to reduce the occurrence of off-gauge in the connecting portion of the line / trailing coil by dividing the three types of thickness change point according to each case.

Description

냉간압연 주행간 판두께 변경구간에서의 두께제어방법{METHOD FOR CONTROLLING THICKNESS OF STRIP AT COLD ROLLING MILL}Thickness Control Method in Sheet Thickness Change Section between Cold Rolling Driving {METHOD FOR CONTROLLING THICKNESS OF STRIP AT COLD ROLLING MILL}

본 발명은 냉간압연 주행간 판두께변경구간에서의 두께제어방법에 관한 것으로써, 더욱 상세하게는 연속 냉간 압연에서 코일과 코일의 연결부위가 밀(Mill)을 통과할 때 코일의 선단부(top) 및 후단부(tail)에서 수요가 요구 두께의 상/하한을벗어나는 오프게이지의 길이를 감소시킬 수 있도록 된 냉간압연 주행간 판두께 변경구간에서의 두께제어방법에 관한 것이다.The present invention relates to a thickness control method in a plate thickness change section during cold rolling running, and more particularly, in the case of continuous cold rolling, a coil top when a connection portion of the coil passes through a mill. And a thickness control method in a plate thickness change section between cold rolling running such that at the tail end, the length of the off-gauge whose demand falls outside the upper and lower limits of the required thickness can be reduced.

일반적으로 연속냉간압연에서 코일과 코일의 연결부위가 밀을 통과하는 경우에 코일의 선단부 및 후단부에서 수요가 요구 두께의 상/하한을 벗어나는 오프게이지(off gauge:수요가가 원하는 치수를 벗어나는 경우)가 발생된다. 통상 코일의 연결부위는 가감속작업과 컷팅(cutting) 및 판두께 변경작업이 이루어지기 때문에 정상압연부에 비해 두께정도가 떨어지는 것은 일반적인 현상이며 이 부분에 대한 두께정도를 향상시키기 위한 많은 활동이 이루어지고 있다.In general, in case of continuous cold rolling, when the coil and coil connection part passes through the mill, the off gauge when demand exceeds the upper and lower limits of the required thickness at the tip and the rear end of the coil. ) Is generated. Normally, the connection part of the coil is accelerating and decelerating, cutting (cutting), and changing plate thickness. Therefore, the thickness is generally lower than that of the normal rolling part, and a lot of activities have been made to improve the thickness of this part. ought.

도 1은 이러한 종래의 선/후행코일 연결부위에 대한 두께제어방법을 도시한 플로우차트이다. 도 1에 도시된 바와 같이, 종래의 이러한 기술들은 코일연결부위를 선/후행코일정보를 수신하여 코일두께,폭,강종등이 일치하는가에 따라 일반용접부(WP:welding point)와 두께변경점(GP:gauge change point)의 두가지로 구분하여 두께를 제어하는 방식을 취하여 오프게이지(off gauge)길이를 감소시켜 왔다. 한편, 전후 코일의 연결부위인 일반 용접부(WP)의 경우에는 자동두께제어시스템(AGC)를 사용하여 두께편차를 감소시킨다.FIG. 1 is a flowchart illustrating a thickness control method for a conventional lead / trailing coil connection portion. As shown in FIG. 1, these conventional techniques receive the pre / following coil information at the coil connection part and according to whether the coil thickness, width, steel grade, etc. match, the welding point (WP) and the thickness change point (GP) The thickness of the off gauge has been reduced by controlling the thickness by dividing it into two types: gauge change point. On the other hand, in the case of the general welding portion WP, which is a connecting portion of the front and rear coils, an automatic thickness control system AGC is used to reduce the thickness deviation.

여기서 자동두께 제어시스템이란 압연중 판두께 측정기로 측정된 압연판의 두께가 목표치와 다른 경우 발생된 두께편차에 비례하여 롤갭이나 롤스피드를 미세조정함으로써 판두께제어를 실시하는 것이다. 즉, 스탠드 입/출측에 설치된 두께측정기로 목표두께와의 편차를 측정하여 다음의 수학식 1 에 의해 롤갭제어량을 구하여 이를 밀하부 푸쉬업 실린더를 제어함으로써 코일두께를 제어하는 방식이다.Here, the automatic thickness control system is to control the plate thickness by finely adjusting the roll gap or the roll speed in proportion to the thickness deviation generated when the thickness of the rolled plate measured by the plate thickness gauge during rolling is different from the target value. That is, the coil thickness is controlled by measuring a deviation from the target thickness using a thickness measuring device installed at the stand entry / exit side, obtaining a roll gap control amount according to Equation 1 below, and controlling the lower push-up cylinder.

ΔSFB= Mh/K * ΔhΔS FB = M h / K * Δh

여기서, ΔSFF:피드포워드(feedforward)롤갭제어량, ΔSFB:피드백(feedback)롤갭제어량, K:압연기의 강성, MH: 입측소성계수, Mh:출측 소성계수이다.Here, ΔS FF : feedforward roll gap control amount, ΔS FB : feedback roll gap control amount, K: rolling mill stiffness, M H : side firing coefficient, M h : exit plasticity coefficient.

두께변경점(GP)의 경우에는 자동두께 제어시스템(AGC)를 오프시키는 대신 차압연재의 압연설정값을 계산하여 코일연결부위가 압연기의 롤바이트(roll bite)를 통과하는 순간에 롤갭과 롤스피드를 설정하는 방식을 채택하였다. 이때, 차압연재의 롤갭(S)은 다음의 수학식2에 의해 구할 수 있다.In the case of the thickness change point (GP), instead of turning off the automatic thickness control system (AGC), the rolling set value of the differential rolling material is calculated to close the roll gap and the roll speed at the moment when the coil connection part passes the roll bite of the rolling mill. Adopted a setting method. At this time, the roll gap S of the differential rolling material can be obtained by the following equation (2).

여기서, H:입측두께, h:출측두께, tf:전방장력, tb:후방장력, K:변형저항, μ:마찰계수, B:판폭, RI:롤 편평반경이다.Where: H: side thickness, h: exit thickness, t f : front tension, t b : rear tension, K: strain resistance, mu: friction coefficient, B: sheet width, R I : roll flat radius.

한편, 아래의 표1은 종래 두께변경점 통과시의 제어방식의 일예를 나타낸 것이다.On the other hand, Table 1 below shows an example of the control method when passing through the conventional thickness change point.

구분division #1 스탠드# 1 stand #2 스탠드# 2 stand #3 스탠드# 3 stand #4 스탠드# 4 stand 스피드 #1Speed # 1 V11*V 11 * V12*V 12 * V1 II V 1 II V1 II V 1 II 스피드 #2Speed # 2 V20 V 20 V2S*V 2S * V23*V 23 * V2 II V 2 II 스피드 #3Speed # 3 V30 V 30 V40 V 40 V33*V 33 * V3 II V 3 II 스피드 #4Speed # 4 V40 V 40 V40 V 40 V20 V 20 V4 II V 4 II 롤갭 #1Roll gap # 1 S1 T S 1 T S1 II S 1 II S1 II S 1 II S1 II S 1 II 롤갭 #2Roll gap # 2 S20 S 20 S2 T S 2 T S2 II S 2 II S2 II S 2 II 롤갭 #3Roll gap # 3 S30 S 30 S30 S 30 S3 T S 3 T S3 II S 3 II 롤갭 #4Roll gap # 4 S40 S 40 S40 S 40 S40 S 40 S4 II S 4 II

(이때, fI I II T: 선진율(i:스탠드 No. I:현압연재,II:차압연재),(At this time, f I I II T : Advance rate (i: stand No. I: current rolling material, II: differential rolling material),

Vi0 II: 롤속도(i0:스탠드 No. I:현압연재,II:차압연재),V i0 II : Roll Speed (i0: Stand No. I: String Rolled Material, II: Differential Rolled Material),

Si0 II:롤갭(i0:스탠드 No. I:현압연재,II:차압연재),S i0 II : Roll gap (i0: Stand No. I: String rolling material, II: Differential rolling material),

V11* = ((1+f2I)/(1+f1T))*(h2I/h1i)* V20 ,V11 * = ((1 + f2 I ) / (1 + f1 T )) * (h2 I / h1 i ) * V20,

V12* = ((1+f2T)/(1+f1II))*(h2II/h1II)* V22,V12 * = ((1 + f2 T ) / (1 + f1 II )) * (h2 II / h1 II ) * V22,

V22* = ((1+f3I)/(1+f2T))*(h3I/h2i)* V30,V22 * = ((1 + f3 I ) / (1 + f2 T )) * (h3 I / h2 i ) * V30,

V23* = ((1+f3T)/(1+f2II))*(h3II/h2III)* V33,V23 * = ((1 + f3 T ) / (1 + f2 II )) * (h3 II / h2I II ) * V33,

V33* = ((1+f4I)/(1+f3T))*(h4I/h3i)* V40 이다.)V33 * = ((1 + f4 I ) / (1 + f3 T )) * (h4 I / h3 i ) * V40.)

또한, 두께변경점의 제어효율을 높이기 위해 코일연결부위에 대한 압연설정계산과 제어를 전담하는 계산장치를 도입하여 효과를 본 경우도 있으나 이러한 경우에는 값비싼 새로운 장비를 도입해야 하기 때문에 비용증가의 문제가 있다. 그러나, 이러한 종래의 판두께제어방법의 경우에 두께변경점(GP:Gauge Change Point)제어의 경우 다음과 같은 문제점을 가지고 있다.In addition, in order to increase the control efficiency of the thickness change point, it is sometimes effective to introduce a calculation device dedicated to the calculation of the rolling setting and control of the coil connection part, but in this case, the cost increases due to the introduction of expensive new equipment. There is. However, in the case of the conventional plate thickness control method, the thickness change point (GP) control has the following problems.

먼저, 코일연결부위는 두께와 재질이 매우 불규칙하고 가감속작업이 이루어져 밀(Mill)특성(마찰계수, 밀 강성 등)이 변하기 때문에 차압연재의 압연설정계산이 부정확하게 되고, 이러한 결과값을 제어에 이용하게 되면 이 오차에 의해 오프게이지가 발생하게 된다. 또한, 코일 연결 부위를 일반 용접부와 두께 변경점(Cutting Point)로 단순하게 구분하여 미소한 두께차의 경우나 큰 두께차의 경우나 동일한 두께제어방식을 채택함으로써 상황에 맞는 두께제어방식을 구현하지 못하고 있다.First, the coil connection part has very irregular thickness and material and acceleration / deceleration is performed, resulting in inaccurate rolling setting calculation of the differential rolling material because mill properties (friction coefficient, stiffness, etc.) are changed. When used in the off-gauge is caused by this error. In addition, by simply dividing the coil connection into a general welding part and a cutting point, it is impossible to realize a thickness control method suitable for a situation by adopting the same thickness control method for a small thickness difference or a large thickness difference. have.

본 발명은 전술한 종래의 문제점을 해결하기 위하여 안출된 것으로써, 그 목적은 코일의 연결부위를 두께변경정도에 따라 세분화하고 이부분이 압연기 롤 바이트를 통과할때 각각의 제어방법을 차별화시켜 정확한 압연셋업을 예측함으로써 오프게이지의 길이를 감소시킬 수 있는 냉간압연 주행간 판두께변경구간에서의 두께제어방법을 제공하고자 하는 것이다.The present invention has been made to solve the above-mentioned conventional problems, the purpose of which is to subdivide the connection part of the coil according to the thickness change degree and to differentiate each control method when this part passes the rolling mill roll bite, The purpose of the present invention is to provide a thickness control method in the plate thickness change section between cold rolling running which can reduce the length of the off gauge by predicting the rolling setup.

도 1은 종래의 선/후행코일 연결부위에 대한 두께제어방법을 도시한 플로우차트이다.1 is a flow chart illustrating a thickness control method for a conventional line / trailing coil connection portion.

도 2는 본 발명에 따른 두께제어방법의 두께변경점 구분과정을 나타낸 플로우차트이다.2 is a flowchart illustrating a thickness change point classification process of the thickness control method according to the present invention.

도 3은 본 발명에 따른 냉간압연 주행간 판두께변경구간에서의 두께제어방법에서의 일반용접부 및 두께변경점 제 1 타입에 대한 두께제어방법을 설명하는 플로우차트이다.FIG. 3 is a flowchart illustrating a thickness control method for a general welding part and a thickness change point first type in a thickness control method in a cold rolling run plate thickness change section according to the present invention.

도 4는 두께변경점의 제 2 및 제 3타입에 대한 두께제어방법을 설명하는 플로우차트를 도시한 것이다.4 shows a flowchart for explaining a thickness control method for the second and third types of thickness change points.

상기한 목적을 달성하기 위하여 본 발명에 따른 냉간압연 주행간 판두께변경구간에서의 두께제어방법은 연속 냉간 압연에서 코일과 코일의 연결부위가 밀을 통과할 때 코일의 선단부 및 후단부에서 발생되는 오프게이지의 길이를 감소시킬 수있도록 된 냉간압연 주행간 판두께 변경구간에서의 두께제어방법에 있어서,In order to achieve the above object, the thickness control method in the plate thickness change section between the cold rolling and running according to the present invention is generated at the leading end and the rear end of the coil when the connection part of the coil and the coil passes through the mill in continuous cold rolling. In the thickness control method in the plate thickness change section between cold rolling running to be able to reduce the length of the off gauge,

상기 선/후행코일의 두께, 폭, 강종데이터를 입력받아 각 데이터를 상호 비교하여 선/후행코일이 동일사이즈, 동일강종인 경우 일반용접부로 구분하고, 선/후행코일의 연결부위가 사이즈 및 강종이 다른 경우에는 각 경우에 따라서 3타입의 두께변경점으로 구분하여 선/후행코일의 연결부위에서의 오프게이지 발생을 감소시킬 수 있도록 한 것을 특징으로 한다.The thickness, width and steel grade data of the line / trailing coil are inputted, and the data are compared with each other.If the line / trailing coil is the same size and the same steel grade, the common welding part is used, and the connection portion of the line / trailing coil is size and steel grade. In this other case, it is possible to reduce the occurrence of off-gauge in the connecting portion of the line / trailing coil by dividing the three types of thickness change point according to each case.

이하에는 본 발명의 일실시예에 따른 냉간압연 주행간 판두께변경구간에서의 두께제어방법의 구성 및 작용효과를 첨부한 도면을 참조하여 상세하게 설명하기로 한다.Hereinafter, with reference to the accompanying drawings, the configuration and operation effects of the thickness control method in the plate thickness change section between the cold rolling running according to an embodiment of the present invention will be described in detail.

도 2는 본 발명에 따른 두께제어방법의 두께변경점 구분과정을 나타낸 플로우차트이다. 도 2에 도시된 바와 같이, 본발명을 구현하기 위한 두께제어방법에서 두께변경점 구분과정을 설명하면, 먼저 단계(s40)에서 프로세스컴퓨터에서는 선/후행 코일의 두께, 폭, 강종데이터를 비교(s42,s44,s46)하여 코일 연결부위를 일반 용접부(WP:welding point)와 3타입의 두께변경점(GP 또는 FGC)으로 구분(s48)하고 각각에 서브코드를 부여한다. 이 결과를 담당하는 각 컴퓨터로 송신함으로써 선/후행 코일의 두께차에 따른 차별화된 제어가 가능하게 된다.2 is a flowchart illustrating a thickness change point classification process of the thickness control method according to the present invention. As illustrated in FIG. 2, in the thickness control method for implementing the present invention, the thickness change point classification process will be described. First, in step S40, the process computer compares the thickness, width, and steel grade data of the line / trailing coil (s42). (s44, s46) to classify the coil connection into a normal welding part (WP) and three types of thickness change points (GP or FGC) (s48) and assign a subcode to each. By transmitting this result to each computer in charge, it is possible to differentiate the control according to the thickness difference between the lead and trailing coils.

이때의 기준은 다음과 같다. 즉, 일반 용접부(WP)는 선/후행코일의 두께, 폭, 강종이 같을 경우에 해당되는 것이고, 두께변경점의 제 1 타입(GP-0)은 선/후행 코일의 두께차가 선행두께의 1.5%미만이고 폭차가 30mm미만이며 동일강종인 경우이고, 제 2 타입(GP-1)은 선/후행 코일의 두께차가 1.5%이상 3.0%미만이고, 폭차가 30mm이상 60mm미만이며 동일강종일때 제 3 타입(GP-2)은 선/후행 코일의 두께차가 3.0%이상이고 폭차가 60mm이상이며 강종이 다른 경우일때로 설정한다.The criteria at this time are as follows. That is, the general welded portion WP corresponds to the case where the thickness, width, and steel grade of the line / trailing coil are the same, and in the first type (GP-0) of the thickness change point, the thickness difference between the line / trailing coil is 1.5% of the preceding thickness. Less than 30mm in width and less than 30mm in width, the second type (GP-1) has a thickness difference of 1.5% or more and less than 3.0% in the thickness of the lead / trailing coil, and a difference in width between 30mm and less than 60mm and in the same steel type. (GP-2) is set when the difference between the thickness of the pre / following coil is more than 3.0%, the width difference is over 60mm and the steel grade is different.

이하 본 발명에 따른 상기의 각 코일연결부위의 세분화된 구분에 따른 각 타입별로 차별화된 두께제어방법에 대해서 설명한다.Hereinafter, a description will be given of a thickness control method differentiated for each type according to the subdivided division of each coil connection portion according to the present invention.

먼저, 상기 프로세스 컴퓨터로부터 구분된 4가지의 타입별 코일연결부위정보를 제어용 컴퓨터인 프로그래머블 로직 제어기(PLC)에서 입력받아 각각의 타입별 최적제어를 실시하게 된다.First, four types of coil connection region information for each type separated from the process computer are inputted from a programmable logic controller (PLC), which is a control computer, to perform optimal control for each type.

도 3은 본 발명에 따른 냉간압연 주행간 판두께변경구간에서의 두께제어방법에서의 일반용접부 및 두께변경점 제 1 타입에 대한 두께제어방법을 설명하는 플로우차트이며, 도 4는 두께변경점의 제 2 및 제 3타입에 대한 두께제어방법을 설명하는 플로우차트를 도시한 것이다.FIG. 3 is a flowchart illustrating a thickness control method for a general welding part and a thickness change point first type in a thickness control method in a cold rolling run plate thickness change period according to the present invention, and FIG. 4 is a second view of a thickness change point. And a flowchart illustrating a thickness control method for the third type.

도 3에 도시된 바와 같이, 먼저 단계(s60)에서 프로세스컴퓨터로부터 선/후행 코일에 대한 각종 정보를 수집하고, 단계(s62)에서는 수집된 정보로부터 상기 도2에 도시된 바와 같은 제어방법을 통해 일반용접부와 두께변경점을 구분하게 된다. 즉, 선/후행코일의 두께,폭 및 강종정보가 모두 동일한 경우에는 일반 용접부로 판단하여 다음 단계(s64)에서 압연기 입/출측의 두께측정기를 통해 설정두께편차를 측정한다. 이는 종래에 설명한 일반 용접부에서의 제어방법과 동일하다. 이렇게 설정두께편차가 측정되면 다음 단계(s66)에서 푸쉬업실린더를 구동시켜 롤갭을 설정두께로 제어하게 된다. 또한, 단계(s68)에서는 푸쉬업실린더의 구동에 따른 현재 롤갭값과 롤갭설정값과의 편차를 비교하여 편차값이 0인 경우에는 푸쉬업실린더의 동작을 오프시킨 뒤 상기 단계(s66)로 복귀하게 된다.As shown in FIG. 3, first, in step s60, various kinds of information about the pre / post coils are collected from the process computer, and in step s62, the collected information is collected through the control method as shown in FIG. 2. Differentiate between normal weld and thickness change That is, if the thickness, width and steel grade information of the line / trailing coil are all the same, it is judged as a general welding part, and the set thickness deviation is measured through the thickness meter at the inlet / outlet of the rolling mill in the next step (s64). This is the same as the control method in the conventional welded part described previously. When the set thickness deviation is measured in this way, the push gap is driven in the next step s66 to control the roll gap to the set thickness. Further, in step s68, the deviation between the current roll gap value and the roll gap setting value according to the driving of the push-up cylinder is compared. If the deviation value is 0, the operation of the push-up cylinder is turned off and then the process returns to the step s66. Done.

한편, 상기 단계(s62)에서 프로세스 컴퓨터로부터 입력받은 선/후행코일간의 정보로부터 판단한 결과 일반 용접부가 아닌 경우에는 두께변경점으로 판단하고 단계(s70)에서는 선/후행코일의 정보로부터 두께변경점을 타입별로 구분하게 된다. 이때 두께변경점을 구분하는 기준은 앞서 설명한 바와 같다. 한편, 두께변경점을 구분한 결과 제 1 타입(GP-0)으로 판단된 경우 즉, 선/후행 코일의 두께차가 선행두께의 1.5%미만이고 폭차가 30mm미만이며 동일강종인 경우로 판단되면 다음 단계(s72)로 진행하여 압연기 입/출측 두께측정기의 설정두께를 변경시키게 된다.On the other hand, as a result of judging from the information of the line / trailing coil received from the process computer in the step (s62), if it is not a normal welding portion, it is determined as the thickness change point, and in step (s70) the thickness change point from the information of the line / trailing coil by type Will be distinguished. At this time, the criteria for distinguishing the thickness change point is as described above. On the other hand, when it is determined that the thickness change point is classified as the first type (GP-0), that is, when the thickness difference between the line / trailing coil is less than 1.5% of the preceding thickness, the width difference is less than 30mm, and the same steel type, the next step is performed. Proceeding to s72, the set thickness of the rolling mill entry / exit thickness gauge is changed.

이는 제 1 타입(GP-0)와 같이 선/후행두께차가 아주 작을때에는 새로운 롤갭, 롤스피드의 계산 및 설정없이 각 스탠드 전/후단의 두께측정기의 설정(Set)값만 변경하고 자동두께제어시스템에 의한 제어를 실시한다. 즉, 이때의 제어는 일반용접부에 대한 제어방법과 동일하다. 이러한 경우 셋업 계산을 실시하지 않음으로써 셋업 계산 에러에 의한 오프게이지를 방지할 수 있고, 자동두께 제어시스템을 계속 적용함으로써 목표두께로 신속히 제어될 수 있다.Like the first type (GP-0), when the difference between the line and the trailing thickness is very small, only the set value of the thickness gauge before and after each stand is changed without calculating and setting new roll gap and roll speed. Control is performed. That is, the control at this time is the same as the control method for the general weld. In this case, the off-gauge caused by the setup calculation error can be prevented by not performing the setup calculation, and it can be quickly controlled to the target thickness by continuously applying the automatic thickness control system.

한편, 도 4에 도시한 바와 같이, 두께 변경점이 제 2 타입(GP-1)인 경우에는 선/후행코일의 두께편차가 크지도 작지도 않을 경우에는 차압연재의 셋업설정과 자동두께 제어시스템(AGC)을 동시에 적용함으로써 다음의 수학식 3과 같이 셋업설정 에러를 자동두께 제어시스템으로 상쇄하는 효과를 얻을 수 있다.On the other hand, as shown in Fig. 4, in the case where the thickness change point is the second type GP-1, when the thickness deviation of the line / trailing coil is neither large nor small, the setup of the differential rolling material and the automatic thickness control system ( By simultaneously applying AGC), it is possible to obtain an effect of canceling the setup error by the automatic thickness control system as shown in Equation 3 below.

여기서, ΔSNEXT: 차압연재의 계산 셋업 롤갭값, ΔSCORRECT: 목표두께를 내는 롤갭값, ΔSERROR: 셋업계산 에러 롤갭값, ΔSAGC: 셋업 에러를 제어하는 AGC에 의한 롤갭값을 나타낸다.Here, ΔS NEXT : calculated setup roll gap value of the differential rolling material, ΔS CORRECT : roll gap value giving a target thickness, ΔS ERROR : setup calculation error roll gap value, ΔS AGC : roll gap value by AGC controlling the setup error.

즉, 단계(s80)에서는 상기 수학식 3에 의하여 차압연재의 셋업 롤갭값을 계산하고, 다음 단계(s82)에서 다음 코일스탠드의 롤바이트 진입이 판단되면 자동두께제어시스템의 동작을 오프시키고, 단계(s84)에서 롤갭과 롤스피드를 설정하여 설정된 롤갭 및 롤스피드로 해당 스탠드를 구동시킨다.That is, in step s80, the set roll gap value of the differential rolling material is calculated by Equation 3, and when it is determined that the roll bite of the next coil stand is determined in the next step s82, the operation of the automatic thickness control system is turned off. The roll gap and the roll speed are set at (s84) to drive the stand with the set roll gap and the roll speed.

이때, 다음 단계(s86)에서는 해당 압연 스탠드의 입/출측에 설치된 두께측정기를 통해 각각 압연전/후의 코일 두께를 검출하고, 검출된 데이터를 비교하여 설정 두께편차(ΔH,Δh)를 측정한다.At this time, in the next step s86, the coil thicknesses before and after rolling are respectively detected through a thickness meter installed at the entry / exit side of the corresponding rolling stand, and the set thickness deviations ΔH and Δh are measured by comparing the detected data.

나아가 단계(s88)에서는 재료의 소성계수, 밀 강성을 이용하여 롤갭변화량을 산출하고, 다음 단계(s90)에서는 스탠드 롤 하부의 푸쉬업실린더를 작동시켜 롤갭을 가변제어하게 된다. 또한, 단계(s92)에서는 푸쉬업 실린더의 동작에 따른 롤갭변화량을 검출하여 설정두께값과의 오차가 0이 되었는가를 판단하고, 편차가 0이면 다음 단계(s94)로 진행하여 압연중인 마지막 스탠드를 통과했는가를 판단하여 마지막 스탠드를 통과하지 못한 경우에는 상기 단계(s90)로 복귀하여 롤갭 및 롤갭스피드를 설정하여 이하의 단계를 반복수행하게 된다.Further, in step s88, the roll gap change amount is calculated using the plasticity coefficient and the stiffness of the material, and in the next step s90, the push gap of the lower stand roll is operated to variably control the roll gap. In addition, in step s92, the amount of roll gap change according to the operation of the push-up cylinder is detected to determine whether the error with the set thickness value is 0. If the deviation is 0, the process goes to the next step (s94) and the last stand being rolled is opened. If it is determined that the passage has passed, if the final stand is not passed, the process returns to step S90 to set the roll gap and the roll gap speed to repeat the following steps.

한편, 두께변경점이 제 3 타입(GP-2)인 것으로 판단되면 선/후행 코일의 두께편차가 큰 경우이므로 기존의 방식대로 롤스피드와 롤갭 설정을 실시하되 새로운 자동두께 제어시스템의 오프 타이밍을 밀 전체에서 2개 스탠드로 한정함으로써 소재두께편차나 소재재질 편차에 대한 대응능력을 향상시킬 수 있도록 한다. 또한, 자동두께제어시스템의 오프스타드(off start) 타이밍을 해당 스탠드 전단으로 함으로써 차압연재의 롤갭과 스피드 설정시 제어혼선을 최소화하였으며 자동두께제어시스템 온스타트 타이밍을 해당 스탠드 후단 두께 측정기의 통과시점으로 조정함으로써 코일의 선단부 오프게이지 감소에 기여할 수 있도록 하였다.On the other hand, if it is determined that the thickness change point is the third type (GP-2), the thickness deviation of the lead / trailing coil is large, so that the roll speed and the roll gap are set according to the conventional method, but the off timing of the new automatic thickness control system is pushed. By limiting to two stands in total, it is possible to improve the ability to cope with material thickness deviation or material material deviation. In addition, the off-start timing of the automatic thickness control system is set at the front end of the stand, minimizing the control confusion when setting the roll gap and speed of the differential rolling material, and the automatic thickness control system ounce start timing as the passing point of the thickness tester at the rear end of the stand. The adjustment was made to contribute to the reduction of the off gauge of the tip of the coil.

즉, 이에 대해 설명하면 단계(s100)에서는 상기 수학식 3에 의하여 차압연재의 셋업롤갭값을 산출하고, 단계(s102)에서 자동두께제어시스템의 구동을 오프시킨 후 후행코일이 스탠드 롤 바이트에 진입함이 판단되면 다음 단계(s104)에서 롤갭 및 롤스피드를 설정한다. 또한, 단계(s106)에서는 코일이 해당 스탠드의 출측 두께측정기를 통과하는 지를 판단하여 통과된 이후에는 다음 단계(s108)로 진행하여 해당 스탠드의 자동두께제어시스템을 동작시키게 된다.In other words, in step S100, the setup roll gap value of the differential rolling material is calculated by Equation 3, and after the driving of the automatic thickness control system is turned off in step S102, the trailing coil enters the stand roll bite. If it is determined that the roll gap and the roll speed is set in the next step (s104). In addition, in step s106, after determining whether the coil passes through the exit thickness meter of the stand, the process proceeds to the next step s108 to operate the automatic thickness control system of the stand.

이러한 결과 본 발명에 따른 냉간압연 주행간 판두께변경구간에서의 두께제어방법을 적용함으로써 종래 오프게이지의 길이가 선단부에서 10.0m, 미단부에서 6.2m발생되어 총 16.2m발생된 것에 비해, 본 발명에 의해서는 선단부 오프게이지의 길이가 8.8m, 미단부의 오프게이지길이는 2.9m로 감소하여 총 11.7m로 제어되기 때문에 종래와 비교하여 약 4.5m의 오프게이지가 줄어드는 효과를 얻을 수 있다.As a result, by applying the thickness control method in the plate thickness change section between the cold rolling running according to the present invention, the length of the conventional off gauge is 10.0m at the leading end, 6.2m at the trailing end to generate a total of 16.2m, Since the length of the tip off-gauge is 8.8m, the length of the off-gauge is reduced to 2.9m and controlled to a total of 11.7m, the off-gauge of about 4.5m can be reduced compared to the conventional.

본 발명에 따른 냉간압연 주행간 판두께변경구간에서의 두께제어방법은 전술한 실시예에 국한되지 않고 본 발명의 기술 사상이 허용하는 범위내에서 다양하게 변형하여 실시될 수 있다.The thickness control method in the cold rolling running plate thickness change section according to the present invention is not limited to the above-described embodiment can be carried out by various modifications within the range allowed by the technical idea of the present invention.

이상에서 설명한 바와 같이, 본 발명에 따른 냉간압연 주행간 판두께변경구간에서의 두께제어방법은 연속 냉간 압연에서 코일과 코일의 연결부위가 밀을 통과할 때 선/후행코일의 용접부에 대한 롤갭제어를 정확히 실시할 수 있도록 선/후행코일의 폭,두께,강종에 대한 정보로부터 일반용접부 및 3타입의 두께변경점으로 각각 세분화하고, 각 타입별로 코일연결부에 대한 두께제어를 실시함으로써 연결코일의 선단부 및 후단부에서 발생되는 오프게이지의 길이를 감소시킬 수 있도록 한다.As described above, the thickness control method in the plate thickness change section between the cold rolling running according to the present invention is a roll gap control for the welded portion of the line / trailing coil when the coil and the connection portion of the coil passes through the mill in continuous cold rolling In order to ensure accurate implementation, the information on the width, thickness, and steel grade of the wire / trailing coil is subdivided into general welding parts and three types of thickness change points, respectively, and the thickness control of the coil connection part for each type is performed to control the tip and It is possible to reduce the length of the off gauge generated at the rear end.

따라서, 본 발명에 따른 두께제어방법에 의해 오프게이지의 길이를 감소시킴으로써 수요가 요구값을 만족하는 코일을 생산함으로써 생산효율을 향상시킬 수 있는 효과를 얻을 수 있다.Therefore, by reducing the length of the off gauge by the thickness control method according to the present invention it is possible to obtain the effect of improving the production efficiency by producing a coil that satisfies the demand value.

Claims (5)

연속 냉간 압연에서 코일과 코일의 연결부위가 밀을 통과할 때 코일의 선단부 및 후단부에서 발생되는 오프게이지의 길이를 감소시킬 수 있도록 된 냉간압연 주행간 판두께 변경구간에서의 두께제어방법에 있어서,In continuous cold rolling, in the thickness control method of the plate thickness change section during cold rolling running, the length of the off-gauge generated at the leading end and the rear end of the coil can be reduced when the coil and coil connection part passes through the mill. , 상기 선/후행코일의 두께, 폭, 강종데이터를 입력받아 각 데이터를 상호 비교하여 선/후행코일이 동일사이즈, 동일강종인 경우 일반용접부로 구분하고, 선/후행코일의 연결부위가 사이즈 및 강종이 다른 경우에는 각 경우에 따라서 3타입의 두께변경점으로 구분하여 선/후행코일의 연결부위에서의 오프게이지 발생을 감소시킬 수 있도록 한 것을 특징으로 하는 냉간압연주행간 판두께 변경구간에서의 두께제어방법.The thickness, width and steel grade data of the line / trailing coil are inputted, and the data are compared with each other.If the line / trailing coil is the same size and the same steel grade, the common welding part is used, and the connection portion of the line / trailing coil is size and steel grade. In this case, the thickness control method in the cold rolling run plate thickness change section is characterized in that it is possible to reduce the occurrence of off-gauge at the connecting portion of the line / trailing coil by dividing into three types of thickness change point in each case. . 제 1 항에 있어서,The method of claim 1, 상기 선/후행코일의 두께,폭,강종을 비교한 선/후행 코일의 두께차가 선행두께의 1.5%미만이고 폭차가 30mm미만이며 동일강종인 경우에는 제 1 타입으로 구분하고, 상기 선/후행 코일의 두께차가 1.5%이상 3.0%미만이고, 폭차가 30mm이상 60mm미만이며 동일강종인 경우에는 제 2 타입, 상기 선/후행 코일의 두께차가 3.0%이상이고 폭차가 60mm이상이며 강종이 다른 경우에는 제 3 타입으로 구분하는 것을 특징으로 하는 냉간압연주행간 판두께 변경구간에서의 두께제어방법.When the thickness difference of the line / trailer coil, the thickness and width of the line / trailer coil is less than 1.5% of the preceding thickness, the width difference is less than 30mm, and the same steel class is divided into the first type. If the thickness difference of more than 1.5% and less than 3.0%, the width difference is more than 30mm and less than 60mm, the same type of steel, the second type, the difference between the thickness of the wire / trailing coil is more than 3.0% and the width difference is more than 60mm, Thickness control method in the plate thickness change section between cold rolling, characterized in that divided into three types. 제 1 항 또는 제 2 항에 있어서, 상기 두께변경점의 제 1 타입인 경우에는 새로운 롤갭,롤스피드의 계산이나 설정없이 각 스탠드 전/후단의 두께측정기 설정값만 변경하여 자동두께제어시스템을 통해 제어를 실시하는 것을 특징으로 하는 냉간압연주행간 판두께변경구간에서의 두께제어방법.According to claim 1 or 2, in the case of the first type of the thickness change point is controlled by the automatic thickness control system by changing only the thickness meter setting value before / after each stand without calculating or setting new roll gap and roll speed. Thickness control method in the cold-rolled running plate thickness change section, characterized in that for performing. 제 1 항 또는 제 2 항에 있어서, 상기 두께변경점의 제 2 타입인 경우에는 차압연재의 롤갭셋업설정을 다음의 식에 의해 계산하여 셋업계산 에러를 자동두께제어시스템에 의한 제어로 상쇄시키도록 된 것을 특징으로 하는 냉간압연주행간 판두께변경구간에서의 두게제어방법.The method of claim 1 or 2, wherein in the case of the second type of the thickness change point, the roll gap setup setting of the differential rolling material is calculated by the following equation to offset the setup calculation error by the control by the automatic thickness control system. The thickness control method in the plate thickness change section between the cold rolling running. ΔSNEXT= (ΔSCORRECT+ ΔSERROR) - ΔSAGC ΔS NEXT = (ΔS CORRECT + ΔS ERROR )-ΔS AGC (ΔSNEXT: 차압연재의 계산 셋업 롤갭값, ΔSCORRECT: 목표두께를 내는 롤갭값, ΔSERROR: 셋업계산 에러 롤갭값, ΔSAGC: 셋업 에러를 제어하는 AGC에 의한 롤갭값).(ΔS NEXT : Calculation setup roll gap value of differential rolling material, ΔS CORRECT : Roll gap value giving a target thickness, ΔS ERROR : Setup calculation error roll gap value, ΔS AGC : Roll gap value by AGC controlling the setup error) 제 1 항 또는 제 2 항에 있어서,The method according to claim 1 or 2, 두께변경점의 제 3 타입인 경우에는 자동두께제어시스템의 오프스타트 타이밍을 해당 스탠드의 전단으로 설정하고, 자동두께제어시스템의 온스타트 타이밍은 해당 스탠드 후단두께측정기로 해당 코일이 통과되는 시점으로 설정한 것을 특징으로 하는 냉간압연 주행간 판두께변경구간에서의 두께제어방법.In the case of the third type of thickness change point, the off-start timing of the automatic thickness control system is set to the front of the stand, and the ounce start timing of the automatic thickness control system is set to the point at which the coil passes through the stand thickness gauge. The thickness control method in the plate thickness change section between the cold rolling running.
KR10-1999-0062132A 1999-12-24 1999-12-24 Method for controlling thickness of strip at cold rolling mill KR100448620B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR10-1999-0062132A KR100448620B1 (en) 1999-12-24 1999-12-24 Method for controlling thickness of strip at cold rolling mill

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR10-1999-0062132A KR100448620B1 (en) 1999-12-24 1999-12-24 Method for controlling thickness of strip at cold rolling mill

Publications (2)

Publication Number Publication Date
KR20010064018A KR20010064018A (en) 2001-07-09
KR100448620B1 true KR100448620B1 (en) 2004-09-13

Family

ID=19629687

Family Applications (1)

Application Number Title Priority Date Filing Date
KR10-1999-0062132A KR100448620B1 (en) 1999-12-24 1999-12-24 Method for controlling thickness of strip at cold rolling mill

Country Status (1)

Country Link
KR (1) KR100448620B1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100797253B1 (en) * 2006-12-22 2008-01-23 주식회사 포스코 Off-gage reduction apparatus of reversing mill
IT202000000316A1 (en) * 2020-01-10 2021-07-10 Danieli Off Mecc METHOD AND APPARATUS FOR THE PRODUCTION OF FLAT METALLIC PRODUCTS
KR102370392B1 (en) * 2020-05-28 2022-03-04 현대제철 주식회사 Apparatus for controlling thickness of slab and control method therefor

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0679325A (en) * 1992-09-04 1994-03-22 Nkk Corp Method for rolling welded part of continuous cold mill
JPH0679326A (en) * 1992-09-08 1994-03-22 Nkk Corp Method for rolling welded part of continuous cold mill
KR960037150A (en) * 1995-04-18 1996-11-19 도사끼 시노부 Rolling method of steel strip joint at continuous hot rolling
KR970005423A (en) * 1995-07-10 1997-02-19 도사끼 시노부 Continuous Hot Rolling Finishing Rolling Method and Apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0679325A (en) * 1992-09-04 1994-03-22 Nkk Corp Method for rolling welded part of continuous cold mill
JPH0679326A (en) * 1992-09-08 1994-03-22 Nkk Corp Method for rolling welded part of continuous cold mill
KR960037150A (en) * 1995-04-18 1996-11-19 도사끼 시노부 Rolling method of steel strip joint at continuous hot rolling
KR970005423A (en) * 1995-07-10 1997-02-19 도사끼 시노부 Continuous Hot Rolling Finishing Rolling Method and Apparatus

Also Published As

Publication number Publication date
KR20010064018A (en) 2001-07-09

Similar Documents

Publication Publication Date Title
DE102010014350B4 (en) Rolling mill, rolling apparatus and control method therefor
EP1833624B1 (en) Operating method for a rolling train and corresponding devices
CN101905246A (en) Automatic control method for dynamic variable specification welding seam of rolling mill
KR100448620B1 (en) Method for controlling thickness of strip at cold rolling mill
US6185967B1 (en) Strip threading speed controlling apparatus for tandem rolling mill
EP0109235B1 (en) Rolling mill control for tandem rolling
US20230032062A1 (en) Method for operating a system of the iron and steel industry
JP2981051B2 (en) Control method of steel sheet surface roughness in temper rolling
JP5637906B2 (en) Thickness control method and thickness control device for cold rolling mill
KOndo et al. A new automatic gauge control system for a reversing cold mill
JP3347572B2 (en) Meandering control method for tandem rolling mill
KR100354209B1 (en) How to Change the Set Point in Open Continuous Rolling _
JP2719216B2 (en) Edge drop control method for sheet rolling
Mori et al. Modernization of gage control system at Sumitomo Wakayama 5-stand cold mill
JP2675175B2 (en) How to measure the warp of the strip
JPH06339726A (en) Method for controlling side guide
KR100979038B1 (en) A method for preventing a strip tail from folding or tearing in multi-stage rolling mill
EP1097008B1 (en) A method and a device for controlling tail dimensions in a rolling mill
KR20020052757A (en) Asymmetry shape distinction method of cold strip and control volume compensation method using the distinction method
JP3443974B2 (en) Roll gap setting method
JP2719215B2 (en) Edge drop control method for sheet rolling
JP2907419B2 (en) Method of controlling elongation of rolled sheet material in rolling equipment
JPH06179006A (en) Method for changing and rolling sheet thickness of running hot rolled strip
JP2541989B2 (en) Temper rolling method in continuous annealing equipment
JPH08103810A (en) Hot continuous finishing mill having meandering prevention function

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E701 Decision to grant or registration of patent right
GRNT Written decision to grant
FPAY Annual fee payment

Payment date: 20080903

Year of fee payment: 5

LAPS Lapse due to unpaid annual fee