EP0134030A1 - Method for reducing or widening mold width during continuous casting - Google Patents

Method for reducing or widening mold width during continuous casting Download PDF

Info

Publication number
EP0134030A1
EP0134030A1 EP84109550A EP84109550A EP0134030A1 EP 0134030 A1 EP0134030 A1 EP 0134030A1 EP 84109550 A EP84109550 A EP 84109550A EP 84109550 A EP84109550 A EP 84109550A EP 0134030 A1 EP0134030 A1 EP 0134030A1
Authority
EP
European Patent Office
Prior art keywords
narrow side
side wall
inclination
speed
moving
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
EP84109550A
Other languages
German (de)
English (en)
French (fr)
Inventor
Wataru c/o Sakai Seitetsusho of Ohashi
Takeyoshi c/o Sakai Seitetsusho of Ninomiya
Masami c/o Sakai Seitetsusho of Temma
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Corp
Original Assignee
Nippon Steel Corp
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
Priority claimed from JP58146843A external-priority patent/JPS6037253A/ja
Priority claimed from JP15848483A external-priority patent/JPS6068137A/ja
Application filed by Nippon Steel Corp filed Critical Nippon Steel Corp
Publication of EP0134030A1 publication Critical patent/EP0134030A1/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • 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
    • B22D11/168—Controlling or regulating processes or operations for adjusting the mould size or mould taper

Definitions

  • This invention relates to a method of reducing or widening mold width during continuous casting.
  • the narrow side walls When the inclination angle of the narrow side walls is changed, generally, the narrow side walls are inclined and supported on the ends of the vertical shaft of a cylinder or the upper or lower end point of the narrow side walls.
  • the inclination angle changing rate is set and controlled at a constant rate established experimentally on the basis of the moving speed of the upper and lower ends of the narrow side walls. Therefore, when the casting speed or the inclination angle changing rate leaves a predetermined range, and thus, the casting speed becomes high, or the inclination angle changing rate becomes low, an air gap tends to break out. This outbreak of an air gap entails a risk of insufficient cooling of a casting strand and production of break out after drawing.
  • the inventors experimentally have obtained the result that when the air gap at the lower part of the mold is more than 2 mm, there is much risk of break out and the like.
  • a continuous casting strand be conducted at a high temperature, and a direct rolling which connects the casting with a succeeding-process, namely a rolling line, has found a wide use.
  • This has caused the development of a tendency for the casting speed to be more and more increased, and there have been various attempts to increase the translational moving speed so as to vary the width at the possible highest speed and to increase the yield by reducing in size the tapered strand produced by so varying the width.
  • the amount of change in inclination should be increased. That is, if the inclination angle changing rate is set at a constant value as in the prior art, the outbreak rate of an air gap and break out increases very unfavorably in terms of practical use.
  • It is a still further object to provide a stable method for reducing or widening mold width during continuous casting comprising: dividing the movement step of said narrow side wall into a forward inclination step (1), a translational movement step (2) and a backward inclination step (3); in said forward inclining step, increasing the moving speed of the upper part la of said narrow side wall more than that of the lower end lb of said narrow side wall, starting the moving of said upper and lower ends simultaneously or substantially simultaneously, and gradually reducing the difference in the velocity between said upper and lower ends, finally making said movement speeds of said upper and lower ends equal, until said translational movement step has been reached while constantly changing the inclination position; in the translational movement step, moving said narrow side wall with the equal and constant moving speeds of said upper and lower ends; and in said backward inclination step, lowering said moving speed of said upper part more than that of said lower end of said narrow side wall, and gradually increasing the distance of said moving speeds of said upper end and said lower end of said narrow side wall while constantly changing said inclination position and
  • Fig. 1 shows an embodiment of a width variable mold in the prior art in which the narrow side walls are made to be movable.
  • the narrow side wall 1 can be moved forward or backward in the widthwise direction of the casting strand 2 by the cylinder means 31, 32 connected to the upper and lower ends of the casting strand 1. It is known that, to reduce the width in this width variable mold, at the beginning stage of the translational movement of the narrow side wall 1, the inclination angle (a') is made steeper than a predetermined angle (a) in the normal operation and in the final stage of the translational movement it is restored to the predetermined angle (a).
  • the inclination angle changing rate is the rate of the amount of change in inclination AT (t (before changing a width) - t (after changing the width)) in proportion to changing time S ( ) and hereinunder, the inclination angle changing rate at the beginning stage of the movement is represented as V ml , and the inclination angle changing rate at the finishing stage of the movement as V m3 .
  • Fig. 3 schematically shows the movement of the narrow side wall at the time of the reduction of the width in the diagram of velocity.
  • the narrow side wall 1 is moved in the width reducing direction of the casting strand 2 at the inclination angle changing rate of V m1 around the lower point lbl, and the inclination angle a' is made steeper than the predetermined angle.
  • the narrow side wall 2 is next translationally moved at the rate of V m2 , and when the upper end la of the narrow side wall has reached a predetermined width, the angle change enters that of the final stage of the movement.
  • the narrow side wall 1 is moved at the inclinatio angle changing rate of V m3 around the upper end point la l , and the inclination angle a' is restored to the predetermin ed angle a, thereby to reduce the width.
  • FIG. 4 schematically shows the movements of the narrow side wall 1 and the solidified shell of a casting strand 2a at the time of change of the inclination angle at the beginning stage of the movement of the narrow side wall 1, the width of which has started changing. While the upper end la of the narrow side wall moves forward from the point A to the point C at the inclination angle changing rate of V m1 , the solidified shell of the casting strand 2a travels from the point A to A' at the inclination angle changing rate of V.
  • the size of the air gap increases in proportion to the travelling distance (AA') of the solidified shell 2a of the casting strand during the change of the inclination angle of the narrow wall 1 from AB to AD, as is shown in Fig. 5(a).
  • Fig. 5(b) shows the case in which the travelling distance of the solidified shell 2a of the casting strand is shorter than in Fig. 5(a).
  • Figs. 6 to 9 schematically show the movement of the narrow side wall and the movement of the solidified shell of the casting strand as an explanation of the basic concept of changing an inclination angle when the width is reduced.
  • Fig. 6 shows the change of the inclination angle at the beginning stage of the movement, the upper end la of the narrow side wall moves forward by the length ⁇ T and the solidified shell 2a of the casting strand travels from the point A to the point A' while the inclination angle is being changed.
  • the inclination angle can be changed without outbreak of an air gap if the point A' which the solidified shell 2a reaches at the end of changing the inclination angle is set as the center of the rotation radius and the inclination of the narrow side wall 1 is moved so as to be along the rotation surface which shares the center of the rotation radius (hereinunder "the rotation center P"). That is, the point A' is the distance the solidified shell 2a of the casting strand 1 travels at the casting speed of V while the narrow side wall 1 changes the inclination angle ( ⁇ T/V m1 ).
  • Fig. 9 shows the narrow side wall 1 in the state of moving at the time of change in the inclination angle at the finishing stage of the movement.
  • the narrow side wall 1 at the time of change in the inclination angle subsequently moves from Fig. 9(a) to Fig. 9(b) subsequently.
  • the starting point of the movement A' of the solidified shell 2a of the casting strand narrow side wall 1 moves vertically, as is shown by the hatched lines in Fig.
  • the narrow side wall 1 moves such as to be along the rotation surface concentric with the rotation center P or P', and the inclination angle changing rate V m1 V m3 should be maintained at a predetermined speed established by the translational moving speed V m2 and so on. For this reason, the moving speed at the beginning stage of change in the inclination angle becomes the following formula (4) and (5) as is shown in Figs. 6 and 8:
  • the moving speed at the final stage of the change in inclination angle becomes the following formula (6) and (7) : moving speed of the upper end moving speed of the lower end
  • the narrow side wall 1 can move along the rotation surface concentric with the rotation center P, P', if each of the upper and the lower ends of the narrow side wall is made to move at the above moving speed for example by controlling the indentation speed with the cylinder means 31, 32.
  • This invention was used for reducing the width of a casting strand of a size of 1,000 mm x 250 mm to a width of 900 mm during continuous casting.
  • V c 1.6 mm/min
  • the above example varied the width with a minimal air gap, and thus made it possible to eliminate such trouble as break out.
  • the rotation center P was fixed at a predetermined position below or above the mold and the difference in the speed of the upper and lower molds is constant.
  • the rotation center P need not be limited to a determined position, and it is possible to incline the short wall while moving the rotation center P.
  • Figs. 11 and 12 show embodiments for reducing the width while moving the rotation center.
  • Fig. 11 illustrates the width reducing method in which the moving speed of a lower compressing cylinder is increased as greatly as possible so as to minimize the increase in time at the beginning stage of the movement, namely in the forward inclination section (1), and at the final stage of the movement, namely in the backward inclination section (3).
  • the movement of an upper compressing cylinder 5 4a which is connected to the upper part of the back of the narrow side wall of a casting strand starts at a high moving speed V 11 approximately equal to a translational moving speed V
  • the lower compressing cylinder 5 4b which is connected to the lower end of the back of the narrow side wall of the casting strand starts to move at an initial moving speed of V 20 and the speed is gradually increased at an acceleration of a 21 whereby the inclination is changed until a preset time t a is reached, or until the inclination angle becomes a set angle ⁇ relative to the short wall of the casting strand.
  • the moving speed V 21 of the lower compressing cylinder 5 4b when the movement has finished, namely when it has reached the translational movement section, is made equal to the moving speed V 11 of the upper compressing cylinder 5 4a .
  • the narrow side wall When the inclination angle of the narrow side wall reaches a preset angle ⁇ , or when a preset time t a is reached, the narrow side wall is translationally moved to a preset position while increasing the speed of the upper compressor cylinder 5 4 a and the lower compresser cylinder 5 4b .
  • the speed of the lower compressing cylinder 5 4b is slightly decreased and is moved at a moving speed of V 22 , and the speed of the upper compressing cylinder 5 4a is gradually reduced from the moving speed V 12 to the reduced speed of 1 and the inclination is restored, namely in the backward inclination until the inclination angle of the narrow side wall reaches a preset angle ⁇ , or when a preset time t b is reached.
  • the moving speed V 12 of the upper compressing cylinder is made the same as or slightly lower than the moving speed V 32 of the lower compressing cylinder 5 4b .
  • the value of the V 20 and V 12 is preferably not greater than 0.3 V , because if it is more than 0.3 V , the increase in m m deformation resistance of the casting strand becomes large in the backward inclining section (3) and the time span in the forward and backward inclination section increases.
  • a width reducing method in the forward inclination section the lower compressing cylinder 5 4b starts to move a preset lag time t 1 after the upper compressing cylinder 5 4 a starts to move or when the inclination angle of the narrow side wall of the mold becomes a preset angle ⁇ 1 , in order to minimize the increase of time span in the forward inclining section (1) and the backward inclination section (3).
  • the lower compressing cylinder 5 4b is moved and the inclination is restored, namely in the backward inclination, until a preset lag time after the upper compressing cylinder 54a starts to move, or until the inclination angle of the narrow side wall of the mold becomes a preset angle ⁇ 0 .
  • the speed of the upper compressing cylinder 5 4 a is gradually increased in the forward inclination section (1) at an initial speed of V 10 and an acceleration of all, and the speed of the lower compressing cylinder 5 4b is gradually increased at an initial speed of V 20 and an acceleration of ⁇ 21 .
  • the moving speed of the lower compressing cylinder 5 4b does not exceed the moving speed of the upper compressing cylinder 5 4 a and the moving speed V 11 of the upper compressing cylinder 5 4 a and the moving speed V 21 of the lower compressing cylinder 5 4b is made equal to, or slightly lower than, the translational moving speed V m .
  • the moving speed of the upper compressing cylinder 5 4a is gradually decreased from V 11 to a reduced moving speed V 12 and the moving speed of the lower compressing cylinder 5 4b is gradually decreased from the initial moving speed V 11 to a reduced moving speed V 22 .
  • V 20 , V 13 are less than 0.2 m, an air gap breaks out and when they are more than 0.3 V m , the deformation resistance is unfavorably large.
  • V 10 , V 23 are less than 0.6 V m , the inclination angle changing rate becomes long, and further if they are more than 0.8 V , the deformation resitance is unfavorably great.
  • Figs. 13, 14 and 15 show the force required for the transformation of the mold in embodiments of a method for reducing the width of a casting strand in the prior art and that according to the invention.
  • Fig. 13 shows the force required for the transformation of the mold in the prior art.
  • Fmax was confirmed under the following conditions:
  • Figs. 14 and 15 show the force required for the transformation of the casting strand by the speed patterns shown in Figs. 11 and 12.
  • the maximum value approximately equal to the maximum value Fmax required for the transformation of the casting strand in the prior art is produced under the following conditions (19) to (21). In this case an air gap between the casting strand and the narrow side wall of the mold did not break out.
  • the movement section is divided into three sections, namely the forward inclination section (1), the translational movement section (2) and the backward inclination section (3).
  • the forward and the backward sections are provided for the purpose of decreasing the deformation resistance.
  • Figs. 16 (a) and (16(b) when the reduction of the width of the mold is conducted in the normal casting state at a translational movement rate of V , a solidified shell 55 formed at the m point A ought to move downwrad by V c .t mm and to reach the point B after t seconds. However, since a narrow side wall 53 has been moved, it reaches the point C, not B, moving to the left side by V m t.
  • the original casting width is represented as the deformation rate & of is as follows:
  • the width-change of a mold is enabled in the shortest possible time. Therefore, the width-changed portion of the casting strand produced so varying the width can be reduced so as to remarkably increase the yield.
  • the amount of an air gap and the deformation resistance of a shell is possible to be constantly less than the allowable values, and a stable operation without cracking or break out is enabled.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
EP84109550A 1983-08-11 1984-08-10 Method for reducing or widening mold width during continuous casting Withdrawn EP0134030A1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP146843/83 1983-08-11
JP58146843A JPS6037253A (ja) 1983-08-11 1983-08-11 幅可変連続鋳造方法
JP158484/83 1983-08-30
JP15848483A JPS6068137A (ja) 1983-08-30 1983-08-30 鋼の幅可変連続鋳造法

Publications (1)

Publication Number Publication Date
EP0134030A1 true EP0134030A1 (en) 1985-03-13

Family

ID=26477554

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84109550A Withdrawn EP0134030A1 (en) 1983-08-11 1984-08-10 Method for reducing or widening mold width during continuous casting

Country Status (4)

Country Link
EP (1) EP0134030A1 (es)
AU (1) AU551521B2 (es)
BR (1) BR8404013A (es)
ES (1) ES8505567A1 (es)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0914888A1 (de) * 1997-10-31 1999-05-12 Sms Schloemann-Siemag Aktiengesellschaft Stranggiesskokille
AT405147B (de) * 1992-07-08 1999-05-25 Voest Alpine Ind Anlagen Verfahren zum vergrössern der breite eines gussstranges während des kontinuierlichen stranggiessens
CN102240782A (zh) * 2011-08-15 2011-11-16 中冶南方工程技术有限公司 用于小范围连铸结晶器在线调整宽度减小的方法
CN102240788A (zh) * 2011-08-15 2011-11-16 中冶南方工程技术有限公司 用于小范围连铸结晶器在线调整宽度增加的方法
CN102240787A (zh) * 2011-08-15 2011-11-16 中冶南方工程技术有限公司 用于大范围连铸结晶器在线调整宽度增加的方法
CN102240783A (zh) * 2011-08-15 2011-11-16 中冶南方工程技术有限公司 用于大范围连铸结晶器在线调整宽度减小的方法

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0028766A1 (de) * 1979-11-02 1981-05-20 Concast Holding Ag Verfahren und Vorrichtung zum Verändern der Abmessungen eines Stranges beim Stranggiessen
GB2079198A (en) * 1980-07-03 1982-01-20 Nippon Steel Corp A method of reducing the width of a continuous casting mould during casting

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0028766A1 (de) * 1979-11-02 1981-05-20 Concast Holding Ag Verfahren und Vorrichtung zum Verändern der Abmessungen eines Stranges beim Stranggiessen
GB2079198A (en) * 1980-07-03 1982-01-20 Nippon Steel Corp A method of reducing the width of a continuous casting mould during casting

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT405147B (de) * 1992-07-08 1999-05-25 Voest Alpine Ind Anlagen Verfahren zum vergrössern der breite eines gussstranges während des kontinuierlichen stranggiessens
EP0914888A1 (de) * 1997-10-31 1999-05-12 Sms Schloemann-Siemag Aktiengesellschaft Stranggiesskokille
US6142212A (en) * 1997-10-31 2000-11-07 Sms Schloemann-Siemag Aktiengesellschaft Continuous casting mold and method
CN1083306C (zh) * 1997-10-31 2002-04-24 Sms舒路曼-斯玛公司 连铸结晶器及其运作方法
CN102240782A (zh) * 2011-08-15 2011-11-16 中冶南方工程技术有限公司 用于小范围连铸结晶器在线调整宽度减小的方法
CN102240788A (zh) * 2011-08-15 2011-11-16 中冶南方工程技术有限公司 用于小范围连铸结晶器在线调整宽度增加的方法
CN102240787A (zh) * 2011-08-15 2011-11-16 中冶南方工程技术有限公司 用于大范围连铸结晶器在线调整宽度增加的方法
CN102240783A (zh) * 2011-08-15 2011-11-16 中冶南方工程技术有限公司 用于大范围连铸结晶器在线调整宽度减小的方法
CN102240787B (zh) * 2011-08-15 2013-08-14 中冶南方工程技术有限公司 用于大范围连铸结晶器在线调整宽度增加的方法
CN102240783B (zh) * 2011-08-15 2013-08-14 中冶南方工程技术有限公司 用于大范围连铸结晶器在线调整宽度减小的方法
CN102240782B (zh) * 2011-08-15 2013-08-14 中冶南方工程技术有限公司 用于小范围连铸结晶器在线调整宽度减小的方法
CN102240788B (zh) * 2011-08-15 2013-09-18 中冶南方工程技术有限公司 用于小范围连铸结晶器在线调整宽度增加的方法

Also Published As

Publication number Publication date
AU551521B2 (en) 1986-05-01
AU3166284A (en) 1985-02-14
ES535020A0 (es) 1985-06-01
ES8505567A1 (es) 1985-06-01
BR8404013A (pt) 1985-07-16

Similar Documents

Publication Publication Date Title
JPH06344084A (ja) 薄いスラブの連続鋳造用鋳型
US5279354A (en) Method of continuous casting with changing of slab width
EP0134030A1 (en) Method for reducing or widening mold width during continuous casting
KR100304759B1 (ko) 연속주조설비작동방법
JPH0692020B2 (ja) 薄い金属鋳片の連続鋳造法と装置
US3910342A (en) Molds for continuous casting
CA1262611A (en) Method and apparatus for adjusting the narrow-sided- slabs of a continuous-casting mould during the continuous casting of a metal
JPS6229139B2 (es)
US3978909A (en) Mold with convex sidewalls for continuous casting machines
KR100707785B1 (ko) 연속적인 주물을 제조하는 방법 및 장치
US4911226A (en) Method and apparatus for continuously casting strip steel
US4148349A (en) Method for controlling slippage between rolls and a slab in a continuous compression casting apparatus
EP0440650B1 (en) The manufacture of thin metal slab
JP3089608B2 (ja) ビームブランクの連続鋳造方法
KR20010030606A (ko) 다양한 크기의 슬래브 제조 방법 및 장치
JPS58173005A (ja) エンドレスロ−リング方法
EP0776716A1 (en) Method of continuously casting thin cast pieces
JPS6019795Y2 (ja) 連続鋳造設備における保熱装置
JPH05177310A (ja) 連続鋳造用鋳型とその短辺形状制御方法
JPS61232049A (ja) 連鋳鋳片幅一定制御方法
JPS6033855A (ja) 幅可変連続鋳造法
JP2598356B2 (ja) 双ロール式連続鋳造方法
JPH06179051A (ja) 薄板連続製造方法と装置
JPH0620625B2 (ja) 連続鋳造工程に於ける鋼スラブの温度調整方法
JPH0441048A (ja) 丸鋳片の連続鋳造装置

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): DE GB IT NL

17P Request for examination filed

Effective date: 19850805

17Q First examination report despatched

Effective date: 19860814

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19861225

RIN1 Information on inventor provided before grant (corrected)

Inventor name: NINOMIYA, TAKEYOSHIC/O SAKAI SEITETSUSHO OF

Inventor name: TEMMA, MASAMIC/O SAKAI SEITETSUSHO OF

Inventor name: OHASHI, WATARUC/O SAKAI SEITETSUSHO OF