JPH0543936A - Method for heating grain oriented electrical steel slab - Google Patents
Method for heating grain oriented electrical steel slabInfo
- Publication number
- JPH0543936A JPH0543936A JP20166191A JP20166191A JPH0543936A JP H0543936 A JPH0543936 A JP H0543936A JP 20166191 A JP20166191 A JP 20166191A JP 20166191 A JP20166191 A JP 20166191A JP H0543936 A JPH0543936 A JP H0543936A
- Authority
- JP
- Japan
- Prior art keywords
- slab
- heating furnace
- heating
- electrical steel
- heated
- 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.)
- Granted
Links
Landscapes
- Manufacturing Of Steel Electrode Plates (AREA)
- Control Of Heat Treatment Processes (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は、方向性電磁鋼スラブ
の熱間圧延ラインにおける加熱方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for heating a grain-oriented electrical steel slab in a hot rolling line.
【０００２】[0002]
【従来の技術】方向性電磁鋼板は高磁束密度かつ低鉄損
という優れた磁気特性をもっており、変圧器などの鉄心
材料として広く用いられている。その製造工程におい
て、［１１０］〈００１〉方位に高度に集積した二次再
結晶を得るために、ＭｎＳ，ＡｌＮといった結晶粒方向
を制御するインヒビターを用いている。このインヒビタ
ーが適正に意図した作用をもたらすためには、熱間圧延
に先立つスラブ加熱時にインヒビターを十分に解離固溶
させる必要がある。さらに、スラブを適切な条件で熱間
圧延し、冷却を行って、インヒビターを微細かつ均一に
分散析出させることが重要である。上記インヒビターの
解離固溶のために、スラブをたとえば１２００℃以上に
高温加熱を行っている。2. Description of the Related Art Grain-oriented electrical steel sheets have excellent magnetic properties such as high magnetic flux density and low iron loss, and are widely used as core materials for transformers and the like. In the manufacturing process, an inhibitor such as MnS or AlN that controls the crystal grain direction is used in order to obtain secondary recrystallization highly integrated in the [110] <001> orientation. In order for this inhibitor to properly produce the intended action, it is necessary to sufficiently dissociate and solidify the inhibitor during slab heating prior to hot rolling. Further, it is important that the slab is hot-rolled under appropriate conditions and cooled to disperse and precipitate the inhibitor finely and uniformly. The slab is heated at a high temperature of, for example, 1200 ° C. or higher to dissociate and solidify the inhibitor.
【０００３】上記高温加熱については、たとえば特開昭
６１−６９９４号公報，特開昭６１−６９９２７号公報
などにより開示されている。これら公報で開示された高
温加熱方法は、スラブを１２５０℃程度までガス燃焼型
加熱炉で予備加熱し、その後の高温加熱を不活性雰囲気
に制御した誘導加熱炉で短時間に行う。高温加熱を行う
誘導加熱炉は、熱間圧延ラインに沿うようにして設けら
れている。また、スラブはこれの長手方向に移送され、
昇降可能な炉床により熱間圧延ラインからすくい上げら
れて誘導加熱炉内に装入される。炉内に装入されたスラ
ブは下側のスラブ側面が炉床によって下方より支持され
ており、スラブ上下面が垂直となった姿勢で加熱され
る。The above high temperature heating is disclosed, for example, in Japanese Patent Laid-Open Nos. 61-6994 and 61-69927. In the high temperature heating methods disclosed in these publications, the slab is preheated to about 1250 ° C. in a gas combustion type heating furnace, and the subsequent high temperature heating is performed in a short time in an induction heating furnace controlled to an inert atmosphere. The induction heating furnace that performs high-temperature heating is provided along the hot rolling line. Also, the slab is transported in its longitudinal direction,
It is picked up from the hot rolling line by the vertically movable hearth and charged into the induction heating furnace. The slab charged in the furnace has its lower side surface supported by the hearth from below, and is heated in a posture in which the upper and lower surfaces of the slab are vertical.
【０００４】また、上記ガス燃焼型加熱炉による予備加
熱では、複数のスラブをスラブ幅方向に間隔（装入間
隔）をおいてスラブ幅方向に送りながら加熱する。スラ
ブをこれの幅方向に間隔をおいて送るには、一般にウォ
ーキングビーム式送り装置が用いられている。In the preheating by the gas combustion type heating furnace, a plurality of slabs are heated while being fed in the slab width direction at intervals (charging intervals) in the slab width direction. A walking beam type feeding device is generally used to feed the slab at intervals in the width direction thereof.
【０００５】[0005]
【発明が解決しようとする課題】ガス燃焼型加熱炉によ
る予備加熱では、生産能率の向上のために装入間隔は１
００mm以下程度としている。このような装入間隔である
と、図１の曲線Ｂで示すようにスラブ端部はスラブ中央
部に比べて同じか、それ以下の温度となる。一方、前記
高温加熱では電磁誘導によってスラブ自身が発熱して昇
温するので、スラブの表面温度は誘導加熱炉の炉壁表面
温度および炉内雰囲気温度よりも高くなる。このため
に、スラブ表面は周囲に熱を放射するので、スラブ端部
は他の部分に比べて昇温量が小さい。したがって、スラ
ブ端部の温度がスラブ中央部の温度に比べて同じかそれ
以下であると、高温加熱終了時ではスラブ端部の温度が
他の部分に比べて著しく低く、均一な温度分布が得られ
ない。In the preheating by the gas combustion type heating furnace, the charging interval is 1 in order to improve the production efficiency.
It is about 00 mm or less. With such a charging interval, as shown by the curve B in FIG. 1, the temperature of the slab end is the same as or lower than that of the slab center. On the other hand, in the high temperature heating, the slab itself generates heat by electromagnetic induction to raise the temperature, so that the surface temperature of the slab becomes higher than the surface temperature of the furnace wall of the induction heating furnace and the temperature of the atmosphere in the furnace. For this reason, since the slab surface radiates heat to the surroundings, the temperature rise amount at the slab end portion is smaller than that at other portions. Therefore, if the temperature of the slab end is equal to or lower than the temperature of the slab center, the temperature of the slab end is significantly lower than the other parts at the end of high temperature heating, and a uniform temperature distribution is obtained. I can't.
【０００６】低温となったスラブ端部では、前記インヒ
ビターを十分に解離固溶できないことがある。このよう
なスラブで製造した電磁鋼板の端部分は他の部分に比べ
て磁束密度が低く、鉄損が高くなる。また、このような
スラブを熱間圧延すると、端部分に割れが生じやすいと
いう問題もある。なお、スラブの低温となった部分を所
定温度まで加熱することが考えられるが、スラブの他の
部分を余分に加熱することになり、むだなエネルギを消
費する。At the slab end where the temperature becomes low, the inhibitor may not be sufficiently dissociated to form a solid solution. The magnetic steel sheet manufactured with such a slab has a lower magnetic flux density and higher iron loss than the other portions. Further, when such a slab is hot-rolled, there is a problem that cracks are likely to occur at the end portions. Note that it is conceivable to heat the low temperature portion of the slab to a predetermined temperature, but this causes additional heating of other portions of the slab, which consumes wasteful energy.
【０００７】この発明は、スラブを所定温度に均一に加
熱することができる方向性電磁鋼スラブの加熱方法を提
供しようとするものである。The present invention is intended to provide a method for heating a grain-oriented electrical steel slab capable of uniformly heating the slab to a predetermined temperature.
【０００８】[0008]
【課題を解決するための手段】この発明の方向性電磁鋼
スラブの加熱方法は、複数の電磁鋼スラブをスラブ幅方
向に間隔をおいてスラブ幅方向に送りながらガス燃焼型
加熱炉で予備加熱する。ついで、非酸化性ガス雰囲気の
誘導加熱炉でスラブをこれの側面が水平となった姿勢で
保持して高温加熱し、所定の時間均熱保持する。上記ガ
ス燃焼型加熱炉でスラブを予備加熱する際に、高温加熱
でのスラブ側面近傍の不足昇温量を補償するようにスラ
ブ間隔を設定する。A method for heating a grain-oriented electrical steel slab according to the present invention is a preheating in a gas combustion type heating furnace while feeding a plurality of electrical steel slabs in the slab width direction at intervals. To do. Then, the slab is held in a non-oxidizing gas atmosphere in an induction heating furnace in a posture in which the side surfaces thereof are horizontal and heated at a high temperature, and is held for a predetermined time. When preheating the slab in the gas combustion type heating furnace, the slab interval is set so as to compensate for the insufficient temperature rise amount near the side surface of the slab during high temperature heating.
【０００９】スラブ間隔はガス燃焼型加熱炉および誘導
加熱炉の加熱特性、スラブ寸法などによって異なるが、
従来法より大きく、たとえば１１０〜２００mm程度であ
る。適正なスラブ間隔は、実機について実験で求めるこ
とができる。The slab spacing varies depending on the heating characteristics of the gas combustion type heating furnace and the induction heating furnace, the slab size, etc.
It is larger than the conventional method, for example, about 110 to 200 mm. The proper slab spacing can be experimentally determined for an actual machine.
【００１０】[0010]
【作用】ガス燃焼型加熱炉による予備加熱では、図１の
曲線ＡおよびＢに示すようにスラブ装入間隔によって端
部の温度が大きく変化する。すなわち、装入間隔を広く
すれば、スラブ端部の昇温量は大きくなり、狭くすれば
昇温量は小さくなる。一方、誘導加熱炉では図１の曲線
Ｃで示すようにスラブ端部は昇温量が小さい。したがっ
て、スラブ端部の低い昇温量を補償するように、スラブ
装入間隔を大きくすることにより、端部を中央部と同様
に加熱することができ、スラブの温度分布は均一にな
る。In the preheating by the gas combustion type heating furnace, as shown by the curves A and B in FIG. 1, the temperature of the end portion largely changes depending on the slab charging interval. That is, if the charging interval is widened, the temperature rise amount at the end of the slab becomes large, and if it is narrowed, the temperature rise amount becomes small. On the other hand, in the induction heating furnace, the temperature rise amount is small at the slab end as shown by the curve C in FIG. Therefore, by increasing the slab charging interval so as to compensate for the low temperature rise amount at the end of the slab, the end can be heated similarly to the central part, and the temperature distribution of the slab becomes uniform.
【００１１】[0011]
【実施例】第２図は、この発明の方法を実施する熱間圧
延設備の構成例を模式的に示している。図面に示すよう
に、熱間圧延設備は熱間圧延ラインＬに沿って順次配列
されたガス燃焼型加熱炉１１、誘導加熱炉１３、粗圧延
機３１および仕上圧延機列３２よりなっている。誘導加
熱炉１３は、炉体１４は下方に向かって開口しており、
炉壁１５の外周に加熱コイル１７が取り付けられてい
る。誘導加熱炉１３は、スラブ１の上下面が水平姿勢か
ら垂直姿勢となるようにし９０度転回するスラブ転回装
置２１、炉内のスラブ１を垂直姿勢で支持する炉床２５
および炉床２５を昇降する電動ウインチ２７を備えてい
る。スラブ転回装置２１は、スラブ１を載せる爪２２、
爪２２に連結されたアーム（図示しない）、およびアー
ムを介して爪２２を９０度転回する油圧シリンダ２３か
らなっている。また、誘導加熱炉１３は、スラブ１を上
方より押さえて支持する支持軸２８を備えている。支持
軸２８は、エアーシリンダ２９により昇降される。さら
に、スラブ搬送ラインＬに沿ってローラーテーブル３４
が設けられている。EXAMPLE FIG. 2 schematically shows a structural example of a hot rolling facility for carrying out the method of the present invention. As shown in the drawing, the hot rolling equipment comprises a gas combustion type heating furnace 11, an induction heating furnace 13, a rough rolling mill 31, and a finishing rolling mill row 32 which are sequentially arranged along a hot rolling line L. In the induction heating furnace 13, the furnace body 14 is opened downward,
A heating coil 17 is attached to the outer periphery of the furnace wall 15. The induction heating furnace 13 includes a slab turning device 21 for turning the slab 1 from the horizontal posture to the vertical posture so as to turn from the horizontal posture to a vertical posture, and a hearth 25 for supporting the slab 1 in the furnace in the vertical posture.
And an electric winch 27 for raising and lowering the hearth 25 is provided. The slab turning device 21 includes a pawl 22 on which the slab 1 is placed,
It comprises an arm (not shown) connected to the pawl 22 and a hydraulic cylinder 23 that turns the pawl 22 by 90 degrees via the arm. Further, the induction heating furnace 13 includes a support shaft 28 that supports the slab 1 by pressing it from above. The support shaft 28 is moved up and down by an air cylinder 29. Further, along the slab transportation line L, the roller table 34
Is provided.
【００１２】ここで、上記のように構成された熱間圧延
設備により、連続鋳造法で製造された電磁鋼スラブを加
熱した例について説明する。スラブをガス燃焼型加熱炉
により１１５０℃まで比較的低い昇温速度で予備加熱し
た。スラブの寸法は、長さ８８００mm、幅１０００mm、
厚み２５０mmである。また、スラブの装入間隔Ｄは１５
０mmである。ついで、誘導加熱炉で１３５０℃まで加熱
した。その結果を表１に示す。Here, an example in which the electromagnetic steel slab manufactured by the continuous casting method is heated by the hot rolling equipment configured as described above will be described. The slab was preheated to 1150 ° C. in a gas combustion type heating furnace at a relatively low heating rate. The dimensions of the slab are length 8800mm, width 1000mm,
The thickness is 250 mm. The loading interval D of the slab is 15
It is 0 mm. Then, it was heated to 1350 ° C. in an induction heating furnace. The results are shown in Table 1.
【００１３】[0013]
【表１】 [Table 1]
【００１４】表１から明らかなように、この発明の方法
によればスラブをほとんど均一に加熱することができ
る。As is apparent from Table 1, the slab can be heated almost uniformly according to the method of the present invention.
【００１５】つぎに、高温加熱したスラブを仕上圧延
し、所定の熱処理をして得られた方向性電磁鋼板につい
て磁気特性を測定した。その結果、鉄損値Ｗ17/50 は平
均０．８１０W/kgであり、ばらつきσは０．００３W/kg
であった。また、磁束密度Ｂ6 は平均１．９３０Wb/m2
であり、ばらつきσは０．００２Wb/m2 であった。Next, the magnetic properties of the grain-oriented electrical steel sheet obtained by finish rolling the high temperature heated slab and subjecting it to a predetermined heat treatment were measured. As a result, the iron loss value W 17/50 was 0.810 W / kg on average, and the variation σ was 0.003 W / kg.
Met. The magnetic flux density B 6 is 1.930 Wb / m 2 on average.
And the variation σ was 0.002 Wb / m 2 .
【００１６】[0016]
【発明の効果】この発明によれば、スラブは全体にわた
ってほぼ均一な温度に高温加熱される。したがって、磁
気特性にばらつきのない優れた品質の電磁鋼板を提供す
ることができ、また歩留りの向上を図ることができる。According to the present invention, the slab is heated to a substantially uniform temperature throughout. Therefore, it is possible to provide an electromagnetic steel sheet of excellent quality with no variation in magnetic characteristics, and it is possible to improve the yield.
【図１】スラブ長手方向の温度分布曲線の一例である。FIG. 1 is an example of a temperature distribution curve in a slab longitudinal direction.
【図２】この発明の方法を実施する熱間圧延設備の構成
例を模式的に示す図面である。FIG. 2 is a drawing schematically showing a configuration example of hot rolling equipment for carrying out the method of the present invention.
１ スラブ ２５ 架台 １１ ガス燃焼型加熱炉 ２８ 支持
軸 １３ 誘導加熱炉 ３１ 粗圧
延機 １７ 加熱コイル ３２ 仕上
圧延機列 ２１ スラブ転回装置 ３４ ロー
ラーテーブル1 Slab 25 Frame 11 Gas Combustion Type Heating Furnace 28 Support Shaft 13 Induction Heating Furnace 31 Rough Rolling Machine 17 Heating Coil 32 Finishing Roll Machine Row 21 Slab Rolling Device 34 Roller Table
Claims (1)
隔をおいてスラブ幅方向に送りながらガス燃焼型加熱炉
で予備加熱し、ついで非酸化性ガス雰囲気の誘導加熱炉
でスラブをこれの側面が水平となった姿勢で保持して高
温加熱し、所定の時間均熱保持する方法において、前記
ガス燃焼型加熱炉でスラブを予備加熱する際に、前記高
温加熱でのスラブ側面近傍の不足昇温量を補償するよう
に前記スラブ間隔を設定することを特徴とする方向性電
磁鋼スラブの加熱方法。1. A plurality of magnetic steel slabs are preheated in a gas combustion type heating furnace while being fed in the slab width direction at intervals in the slab width direction, and then the slab is heated in an induction heating furnace in a non-oxidizing gas atmosphere. In a method in which the side surface is held in a horizontal posture and heated at a high temperature, and the temperature is uniformly maintained for a predetermined time, when the slab is preheated in the gas combustion type heating furnace, the vicinity of the slab side surface at the high temperature heating is insufficient A method for heating a grain-oriented electrical steel slab, characterized in that the slab spacing is set so as to compensate for the amount of temperature rise.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3201661A JP2563695B2 (en) | 1991-08-12 | 1991-08-12 | Method of heating grain-oriented electrical steel slabs |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3201661A JP2563695B2 (en) | 1991-08-12 | 1991-08-12 | Method of heating grain-oriented electrical steel slabs |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0543936A true JPH0543936A (en) | 1993-02-23 |
| JP2563695B2 JP2563695B2 (en) | 1996-12-11 |
Family
ID=16444804
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3201661A Expired - Lifetime JP2563695B2 (en) | 1991-08-12 | 1991-08-12 | Method of heating grain-oriented electrical steel slabs |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2563695B2 (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5247179A (en) * | 1975-10-11 | 1977-04-14 | Kayaba Ind Co Ltd | Shock absorber with rolling prevention function |
| JPS6169924A (en) * | 1985-08-24 | 1986-04-10 | Nippon Steel Corp | Method for heating electromagnetic steel slab |
-
1991
- 1991-08-12 JP JP3201661A patent/JP2563695B2/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5247179A (en) * | 1975-10-11 | 1977-04-14 | Kayaba Ind Co Ltd | Shock absorber with rolling prevention function |
| JPS6169924A (en) * | 1985-08-24 | 1986-04-10 | Nippon Steel Corp | Method for heating electromagnetic steel slab |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2563695B2 (en) | 1996-12-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20070116591A1 (en) | Inductive heating process control of continuous cast metallic sheets | |
| JP5271512B2 (en) | Hot rolling equipment | |
| JP2563695B2 (en) | Method of heating grain-oriented electrical steel slabs | |
| JPH0550106A (en) | Method for hot rolling grain oriented electromagnetic steel slab | |
| JP2863351B2 (en) | Heating method of directional magnetic steel slab | |
| RU2348702C1 (en) | Method of thick sheets production | |
| JP3823653B2 (en) | Manufacturing method of high carbon hot rolled steel sheet | |
| JP4085975B2 (en) | Hot rolling method | |
| JPH086142B2 (en) | Method of heating grain-oriented electrical steel slabs | |
| JP3359385B2 (en) | Manufacturing method of unidirectional electrical steel sheet | |
| JP2533987B2 (en) | Hot rolling method for continuous cast slab for unidirectional electrical steel sheet. | |
| JP2703468B2 (en) | Stable manufacturing method of high magnetic flux density unidirectional electrical steel sheet | |
| JP4691839B2 (en) | Steel plate manufacturing method and steel plate manufacturing equipment | |
| JPH0763725B2 (en) | Series of continuous hot rolling equipment for unidirectional electrical steel sheets | |
| JP2580403B2 (en) | Hot rolling method for continuous cast slab for unidirectional electrical steel sheet. | |
| JP4211540B2 (en) | Continuous hot rolling mills for grain oriented electrical steel sheets | |
| JPS5941508B2 (en) | Manufacturing method of titanium hot rolled sheet | |
| JPH02259016A (en) | Production of grain-oriented silicon steel sheet free from surface blister defect | |
| JPH03133501A (en) | Hot rolling method for slab of continuous casting grain -oriented magnetic steel | |
| JPS60190520A (en) | Method for heating grain-oriented electrical steel slab | |
| JP3858546B2 (en) | Manufacturing method of high carbon hot rolled steel sheet | |
| JPH0336214A (en) | Method for continuously annealing non-oriented electrical steel sheet | |
| JPH06212262A (en) | Production of grain-oriented silicon steel sheet having extremely low core loss | |
| JPH075976B2 (en) | Hot Rolling Method for Continuously Cast Slabs for Unidirectional Electrical Steel Sheets | |
| JPS5926370B2 (en) | Method of heating steel billet for hot rolling |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19960730 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20070919 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080919 Year of fee payment: 12 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090919 Year of fee payment: 13 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100919 Year of fee payment: 14 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100919 Year of fee payment: 14 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110919 Year of fee payment: 15 |
|
| EXPY | Cancellation because of completion of term |