KR20020016247A - Method for controlling strand driven roll pressure in the continuous caster - Google Patents
Method for controlling strand driven roll pressure in the continuous caster Download PDFInfo
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- KR20020016247A KR20020016247A KR1020000049469A KR20000049469A KR20020016247A KR 20020016247 A KR20020016247 A KR 20020016247A KR 1020000049469 A KR1020000049469 A KR 1020000049469A KR 20000049469 A KR20000049469 A KR 20000049469A KR 20020016247 A KR20020016247 A KR 20020016247A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/12—Accessories for subsequent treating or working cast stock in situ
- B22D11/128—Accessories for subsequent treating or working cast stock in situ for removing
- B22D11/1287—Rolls; Lubricating, cooling or heating rolls while in use
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Abstract
Description
본 발명은 스트랜드 구동롤의 압하력을 제어하는 방법에 관한 것으로서, 특히 연속주조설비에서 주조 중 생산되는 주편이 롤 중앙부를 중심으로 좌우 편심을 일으키기 때문에 발생하는 불균등한 압하력분포를 주편의 절대위치에 따른 보정제어를 통하여 압하력을 주편표면에 균등하게 분포시키는 연속주조설비에서 스트랜드 구동롤의 압하력을 제어하는 방법에 관한 것이다.The present invention relates to a method for controlling the reduction force of the strand drive roll, and in particular, the absolute position of the slab in the uneven pressure distribution generated due to the left and right eccentricity around the center of the roll produced during casting in the continuous casting equipment The present invention relates to a method of controlling the reduction force of a strand drive roll in a continuous casting facility for uniformly distributing the reduction force on the surface of a cast piece through correction control according to the present invention.
일반적으로 연속주조설비는 도 1에 도시한 바와 같이 용강(2)을 담고있는 턴디쉬(1)와 용강(2)을 1차적으로 냉각시켜 정형화된 크기의 주편(4)을 생성하는 주형(3), 상기 주형(3)을 통과한 주편(4)을 지지하는 역할을 하는 다수의 가이드롤 (7 ) 및 상기 주편(4)을 압하하여 인발하는 다수의 구동롤(6)로 구성된 스트랜드를 구비하여 주조 중에 구동롤(6)을 압하할 수 있는 유압실린더(8)를 설치하여 주편(4 )을 압하함과 동시에 구동롤(6)을 회전시킬 수 있는 구동장치를 설치하여 구동롤(6 )을 회전시키면서 주편(4)을 인발하게 된다.In general, the continuous casting facility is a mold (3) for cooling the tundish (1) containing the molten steel (2) and the molten steel (2) to produce a cast (4) of the standard size as shown in FIG. ), A strand composed of a plurality of guide rolls (7) serving to support the slab (4) passing through the mold (3) and a plurality of driving rolls (6) for pressing and drawing the slab (4) By installing a hydraulic cylinder (8) capable of pressing down the driving roll (6) during casting to press down the cast (4) and at the same time to install a driving device for rotating the driving roll (6) driving roll (6) While rotating the cast (4) is drawn.
상기한 연속주조프로세스에서 주형(3)을 통과한 직후의 주편(4)은 응고셀이 매우 얇기 때문에 도 2에 도시한 바와 같이 주형(3)의 장변부(3-1) 뿐만아니라 단변부(3-2) 직하에도 주편(4)을 지지할 수 있는 측면지지롤(9)이 1 ∼ 5개 정도 설치되어 주편(4)을 지지하고 있으나 측면지지롤(9) 이후에는 설비의 단가 및 복잡성때문에 단변을 지지할 수 있는 장치는 없고 장변에만 가이드롤(7)과 구동롤(6)이설치되어 주편(4)을 지지하여 인발한다.In the continuous casting process described above, the slab 4 immediately after passing through the mold 3 has a very thin solidification cell, and thus, as shown in FIG. 2, not only the long side portion 3-1 of the mold 3 but also the short side portion ( 3-2) 1 to 5 side support rolls 9 which can support the cast steel 4 are installed directly to support the cast steel 4, but after the side support roll 9, the unit cost and complexity Therefore, there is no device capable of supporting the short side, and the guide roll 7 and the driving roll 6 are installed only on the long side to support and pull out the cast 4.
따라서 측면지지롤(9)을 통과한 주편(4)은 스트랜드를 통과하면서 만곡부(5 ) 근처에서부터 불규칙적인 마모 등에 의한 인발롤 좌우의 마찰력 차이 발생요인과 주형(3) 단변부(3-2)의 좌우 비대칭 요인에 의해 주편(4)이 롤의 중앙부를 통과하지 못하고 좌우 한쪽 방향으로 편심되어 스트랜드를 통과하는 것이 일반적인 현상이다.Therefore, the slab 4 passing through the side support roll 9 causes the frictional force difference between the left and right sides of the drawing roll due to irregular wear and the like from the curved portion 5 while passing through the strand, and the mold 3 short side portion 3-2. It is a common phenomenon that the cast piece 4 does not pass through the center portion of the roll and is eccentric in the left and right direction and passes through the strand due to the left and right asymmetry factor.
한편 주편(4)을 인발하는 공정을 살펴보면 구동롤(6) 상부에는 주편을 압하할 수 있는 압하실린더(8)가 설치되어 있어서 주편(4)을 압하함과 동시에 구동롤(6 )을 구동시키는 구동장치가 있어서 구동롤(6)이 회전하면서 주편(4)을 인발하게 되는데, 종래에는 구동롤(6)의 좌우에 존재하는 베어링 하우징(10) 상부에 위치해 있는 압하실린더의 압력을 좌우 똑같이 하여 주편을 압하하면서 인발하므로 좌우 한쪽으로 편심된 주편(4)은 편심된 반대 방향의 주편(4) 표면에 더 많은 힘이 전달되어 생산하는 주편(4)의 한쪽 표면에 롤자국과 같은 흠을 발생시킬 뿐만 아니라 구동롤(6)의 편심을 발생시켜 구동롤(6)의 수명이 단축되는 단점이 있었다.On the other hand, when looking at the process of drawing the cast (4), the driving roller (6) is provided with a pressing cylinder (8) capable of pressing the cast slab to reduce the cast (4) and at the same time to drive the driving roll (6) The driving device 6 draws the cast steel 4 while the driving roll 6 rotates. In the related art, the pressure of the pressing cylinder located on the upper side of the bearing housing 10 existing on the left and right sides of the driving roll 6 is equalized to the left and right. Since the slabs are drawn while pressing the cast pieces, the cast pieces 4 which are eccentric to the left and right sides generate a flaw, such as a roll mark, on one surface of the cast pieces 4 which are produced by transmitting more force to the surface of the cast pieces 4 in the opposite direction. As well as causing the eccentricity of the drive roll 6 there was a disadvantage in that the life of the drive roll 6 is shortened.
본 발명은 상기한 실정을 감안하여 종래 스트랜드 구동롤의 압하력 제어방법에서 야기되는 문제점들을 해결하고자 발명한 것으로서, 연속주조설비에서 주조 중 생산되는 주편이 롤 중앙부를 중심으로 좌우 편심을 일으키기 때문에 발생하는 불균등한 압하력 분포를 주편의 절대위치에 따른 보정제어를 통하여 압하력을 주편표면에 균등하게 분포시키는 연속주조설비에서 스트랜드 구동롤의 압하력을 제어하는방법을 제공함에 그 목적이 있다.The present invention has been invented to solve the problems caused by the conventional method for controlling the rolling force of the strand driving roll in view of the above situation, which occurs because the cast produced during casting in the continuous casting equipment causes the left and right eccentricity around the center of the roll It is an object of the present invention to provide a method for controlling the reduction force of a strand drive roll in a continuous casting facility in which the reduction force is equally distributed on the surface of the slab through correction control according to the absolute position of the slab.
도 1은 연속주조설비의 개략적인 구성도,1 is a schematic configuration diagram of a continuous casting facility,
도 2는 연속주조설비의 주형 및 주형직하 측면지지롤의 구성도,Figure 2 is a configuration of the mold and the mold directly side support roll of the continuous casting equipment,
도 3은 연속주조설비의 구동롤 및 구동롤 압하실린더의 구성도,3 is a configuration diagram of a driving roll and a driving roll pressing cylinder of the continuous casting facility;
도 4는 본 발명이 채용된 구동롤 압하시스템의 구성도이다.4 is a configuration diagram of a drive roll pressing system to which the present invention is employed.
〈도면의 주요부분에 대한 부호의 설명〉<Explanation of symbols for main parts of drawing>
1 : 턴디쉬 2 : 용강1: tundish 2: molten steel
3 : 주형 3-1 : 주형의 장변부3: mold 3-1: long side of the mold
3-2 : 주형의 단변부 4 : 주편3-2: Short side of the mold 4: Cast
5 : 만곡부 6 : 구동롤5 curved portion 6 driving roll
7 : 가이드롤 8 : 압하실린더7: guide roll 8: Absin cylinder
8-1 : 좌측 압하실린더 8-2 : 우측 압하실린더8-1: Left Ablinder 8-2: Right Absorber
9 : 측면지지롤 10 : 베어링 하우징9: side support roll 10: bearing housing
11 : 주편위치측정기 12 : 압력측정기11: caster position measuring instrument 12: pressure measuring instrument
13 : 주형폭제어기 14 : 상위제어기13: mold width controller 14: upper controller
15 : 유압제어기15: hydraulic controller
상기한 목적을 달성하기 위한 본 발명 연속주조설비에서 스트랜드 구동롤의 압하력을 제어하는 방법은 용강(2)을 담고있는 턴디쉬(1)와 용강(2)을 1차적으로 냉각시켜 정형화된 크기의 주편(4)을 생성하는 주형(3), 주형(3)을 통과한 주편(4)을 지지하는 역할을 하는 다수의 가이드롤(7) 및 주편(3)을 압하하여 인발하는 다수의 구동롤(6)로 구성된 스트랜드를 구비한 연속주조설비에 있어서의 구동롤(6)의 압하력을 제어하는 방법에 있어서, 주편위치측정기(11)로 주조되고 있는 주편(4)의 절대위치를 검출하는 단계와; 압력측정기(12)로 주조 중 구동롤(6)을 압하할 때 작용하는 압력을 측정하는 단계; 주형폭제어기(13)로 현재 주조되고 있는 주편폭 정보를 수신하는 단계와; 구동롤(6)의 길이정보와 상기한 주편의 절대위치 및 주편폭 정보로부터 좌,우측 압하실린더에서 작용해야 할 압하력을 산출하는 단계 및; 상기 압력측정기(12)로 측정한 압력이 산출압력과 일치하도록 압하실린더의 유압밸브를 조정하는 단계로 이루어져 압하력을 주편표면에 균등하게 분포시키는 것을 특징으로 한다.Method for controlling the reduction force of the strand drive roll in the continuous casting equipment of the present invention for achieving the above object is the size standardized by cooling the tundish (1) and the molten steel (2) containing the molten steel (1) first A plurality of drives for depressing and drawing the mold (3), the plurality of guide rolls (7) and the cast (3) serving to support the cast (4) passing through the mold (3) to produce the cast (4) of the In the method of controlling the reduction force of the driving roll 6 in the continuous casting facility provided with the strand comprised by the roll 6, the absolute position of the slab 4 cast by the slab position measuring machine 11 is detected. Making a step; Measuring the pressure acting when the driving roll 6 is pressed down during casting with the pressure gauge 12; Receiving cast piece width information currently being cast by the mold width controller 13; Calculating a reduction force to be acted on the left and right pressing cylinders from the length information of the driving roll 6 and the absolute position and slab width information of the cast steel; Adjusting the hydraulic valve of the pressing cylinder so that the pressure measured by the pressure measuring device 12 is equal to the output pressure, it characterized in that the pressing force is distributed evenly on the surface of the cast steel.
그리고 상기 압하력을 산출하는 단계에서는 전체 압하력을 F, 현재 생성되는 주편의 폭을 W, 구동롤의 길이를 L, 구동롤 좌측에서 주편 좌측까지의 거리를 X라고 하며, 좌측 압하실린더에 작용해야 할 압하력(F1)을 F1 = (L - X - W/2 ) ×F/L로서, 우측 압하실린더에 작용해야 할 압하력(F2)을 F2 = (X + W/2) ×F/L로서 산출하는 것을 특징으로 한다.In the step of calculating the reduction force, the total reduction force is F, the width of the currently produced cast steel is W, the length of the driving roll is L, and the distance from the left side of the driving roll to the left side of the cast steel is X, which acts on the left side pressing cylinder. The rolling force to be applied (F1) is F1 = (L-X-W / 2) × F / L, and the rolling force (F2) to be applied to the right side pressing cylinder is set to F2 = (X + W / 2) × F / It calculates as L. It is characterized by the above-mentioned.
이하 첨부 도면을 참조하여 본 발명 연속주조설비에서 스트랜드 구동롤의 압하력을 제어하는 방법에 대하여 상세하게 설명한다.Hereinafter, with reference to the accompanying drawings will be described in detail a method for controlling the reduction force of the strand drive roll in the continuous casting equipment of the present invention.
일반적으로 도 1에 도시한 연속주조설비로 주조 중 주편(4)을 인발할 시에는 주편(4)을 압하함과 동시에 구동롤(6)을 구동시켜 주편(4)을 인발하는 데, 이때 주편(4)을 압하하는 압하력 설정값은 주편폭과 스트랜드 전체에 걸쳐 분포되어 있는 각 구동롤(6)의 위치에 해당하는 용강의 철정압에 비례하는 값을 미리 계산하여 압하력 지령치 테이블로 작성하여 이용한다.In general, in the case of drawing the cast 4 during casting with the continuous casting equipment shown in Figure 1, while pressing the cast 4 and at the same time driving the drive roll 6 to draw the cast 4, the cast (4) The rolling force setting value for rolling down (4) is calculated by preliminarily calculating the value proportional to the iron static pressure of the molten steel corresponding to the width of the cast steel and the position of each driving roll 6 distributed throughout the strand, and preparing the rolling force command value table. To use.
도 3은 연속주조설비의 구동롤 및 구동롤 압하실린더의 구성도, 도 4는 본 발명에 채용한 구동롤의 압하력 제어장치를 나타낸 것으로서, 상위제어기(14)에는 각 구동롤(6)에서 압하해야 하는 압하력을 미리 설정해 두고, 구동롤(6)의 길이는 비주조중에 미리 측정하며, 몰드폭제어기로부터 현재 주조되고 있는 주편(4)의 폭 정보를 입수하고, 만곡부(5) 근처에는 주편(4)의 절대위치를 측정할 수 있는 주편위치측정기(11)를 설치하여 주편(4)의 절대위치를 측정하여 하기 수학식 1, 2에 따라 주편 표면에 압하력을 균일하게 분포시키기 위한 좌우 압하실린더(8-1),(8-2)에서 압하해야 하는 압하력 지령값을 계산한다.3 is a configuration diagram of a driving roll and a driving roll pressing cylinder of a continuous casting machine, and FIG. 4 shows a pressure reduction force control device of the driving roll employed in the present invention. The pressing force to be pressed is set in advance, and the length of the driving roll 6 is measured in advance during non-casting, and the width information of the cast steel 4 currently being cast is obtained from the mold width controller, and near the curved portion 5 To measure the absolute position of the cast steel 4 by installing a caster position measuring instrument 11 capable of measuring the absolute position of the cast steel 4 to uniformly distribute the pressing force on the surface of the cast steel according to the following equations (1) and (2). Calculate the reduction force command value to be reduced in the left and right pressure cylinders 8-1 and 8-2.
상기 수학식 1,2에서 F는 전체 압하력, W는 현재 생성되는 주편의 폭이고, L은 구동롤의 길이이며, X는 구동롤 좌측에서 주편 좌측까지의 거리이다. 따라서 구동롤 우측에서 주편 우측까지의 거리(Y)는 L - X - \ 로 된다. 또한 F1은 좌측 압하실린더에서 작용해야 할 압하력이고, F2는 우측 압하실린더에서 작용해야 할 압하력이다.In Equation 1, 2, F is the total reduction force, W is the width of the currently produced cast steel, L is the length of the driving roll, X is the distance from the left side of the driving roll to the left side of the cast steel. Therefore, the distance Y from the right side of the driving roll to the right side of the cast piece is L-X-\. In addition, F1 is the reduction force to be applied to the left side of the cylinder, F2 is the reduction force to act to the right side of the cylinder.
상기 수학식 1, 2에 의해 구해진 압하력 지령값이 유압제어기(15)에 하달되면 유압제어기(15)는 압하실린더에 설치되어 있는 압력측정기(12)로부터 측정되는 압력이 상기 수학식 1, 2에 의해 구해진 압하력 지령값과 일치하도록 각 압하실린더의 유압밸브를 조정하여 압력을 제어하게 된다.When the pressure reduction command value obtained by the above equations 1 and 2 reaches the oil pressure controller 15, the oil pressure controller 15 measures the pressure measured from the pressure measuring device 12 installed in the pressure cylinder. The pressure is controlled by adjusting the hydraulic valves of the respective push cylinders so as to coincide with the reduction force command value obtained by the step.
상기한 바와 같이 본 발명은 주조 중 스트랜드 구동롤의 압하력을 주편의 절대위치에 따라 보정하여 제어함으로써 주편의 표면에 발생하는 표면흠을 감소시킬 수 있을 뿐만 아니라 구동롤의 수명을 향상시킬 수 있는 장점이 있다.As described above, the present invention can not only reduce the surface defects occurring on the surface of the cast steel but also improve the life of the driving roll by controlling the rolling force of the strand driving roll during casting according to the absolute position of the cast steel. There is an advantage.
Claims (2)
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Application Number | Priority Date | Filing Date | Title |
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KR10-2000-0049469A KR100384450B1 (en) | 2000-08-25 | 2000-08-25 | Method for controlling strand driven roll pressure in the continuous caster |
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KR10-2000-0049469A KR100384450B1 (en) | 2000-08-25 | 2000-08-25 | Method for controlling strand driven roll pressure in the continuous caster |
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KR100384450B1 KR100384450B1 (en) | 2003-05-22 |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20030017152A (en) * | 2001-08-24 | 2003-03-03 | 재단법인 포항산업과학연구원 | Method for controlling strand driven roll pressure in the continuous caster |
KR100472531B1 (en) * | 2002-08-29 | 2005-03-08 | 재단법인 포항산업과학연구원 | The control method of driven roll pressure in continuous casting equipments |
KR100895069B1 (en) * | 2002-08-29 | 2009-05-04 | 재단법인 포항산업과학연구원 | The control method of driven roll pressure in mold width change |
CN109500370A (en) * | 2018-11-12 | 2019-03-22 | 包头钢铁(集团)有限责任公司 | A kind of method of novel Wide and Thick Slab casting machine pressure control dynamic soft-reduction |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
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KR101053973B1 (en) | 2008-12-30 | 2011-08-04 | 주식회사 포스코 | Measuring device for measuring alignment deviation of segment girder and correcting misalignment |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
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JPS5954455A (en) * | 1982-09-21 | 1984-03-29 | Nippon Steel Corp | Method for controlling pressing force of billet guiding and pressing roll in continuous casting machine |
JPS62130759A (en) * | 1985-12-02 | 1987-06-13 | Sumitomo Metal Ind Ltd | Method for controlling leveling roll for continuously cast steel ingot |
JP3068839B2 (en) * | 1990-08-24 | 2000-07-24 | 日新製鋼株式会社 | Slab thickness control method in twin roll continuous casting |
KR100276345B1 (en) * | 1998-06-22 | 2000-12-15 | 이구택 | A method for controlling roll gap of twin roll strip casting device |
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2000
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20030017152A (en) * | 2001-08-24 | 2003-03-03 | 재단법인 포항산업과학연구원 | Method for controlling strand driven roll pressure in the continuous caster |
KR100472531B1 (en) * | 2002-08-29 | 2005-03-08 | 재단법인 포항산업과학연구원 | The control method of driven roll pressure in continuous casting equipments |
KR100895069B1 (en) * | 2002-08-29 | 2009-05-04 | 재단법인 포항산업과학연구원 | The control method of driven roll pressure in mold width change |
CN109500370A (en) * | 2018-11-12 | 2019-03-22 | 包头钢铁(集团)有限责任公司 | A kind of method of novel Wide and Thick Slab casting machine pressure control dynamic soft-reduction |
CN109500370B (en) * | 2018-11-12 | 2020-12-22 | 包头钢铁(集团)有限责任公司 | Method for controlling dynamic soft reduction by pressure of wide and thick plate casting machine |
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