JPS6257427B2 - - Google Patents
Info
- Publication number
- JPS6257427B2 JPS6257427B2 JP59132720A JP13272084A JPS6257427B2 JP S6257427 B2 JPS6257427 B2 JP S6257427B2 JP 59132720 A JP59132720 A JP 59132720A JP 13272084 A JP13272084 A JP 13272084A JP S6257427 B2 JPS6257427 B2 JP S6257427B2
- Authority
- JP
- Japan
- Prior art keywords
- molten steel
- amount
- ladle
- magnetic field
- change point
- 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.)
- Expired
Links
- 229910000831 Steel Inorganic materials 0.000 claims description 125
- 239000010959 steel Substances 0.000 claims description 125
- 238000000034 method Methods 0.000 claims description 48
- 238000001514 detection method Methods 0.000 claims description 36
- 230000005284 excitation Effects 0.000 claims description 19
- 238000005259 measurement Methods 0.000 claims description 18
- 239000002184 metal Substances 0.000 claims description 8
- 229910052751 metal Inorganic materials 0.000 claims description 8
- 230000003628 erosive effect Effects 0.000 claims description 6
- 239000011819 refractory material Substances 0.000 claims description 5
- 239000002893 slag Substances 0.000 description 26
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 16
- 238000005266 casting Methods 0.000 description 9
- 238000009749 continuous casting Methods 0.000 description 8
- 238000010586 diagram Methods 0.000 description 7
- 238000002844 melting Methods 0.000 description 7
- 230000008018 melting Effects 0.000 description 7
- 230000007423 decrease Effects 0.000 description 6
- 230000007547 defect Effects 0.000 description 5
- 238000009826 distribution Methods 0.000 description 5
- 239000000155 melt Substances 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 238000012937 correction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000002436 steel type Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
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
- B22D11/18—Controlling or regulating processes or operations for pouring
- B22D11/181—Controlling or regulating processes or operations for pouring responsive to molten metal level or slag level
- B22D11/186—Controlling or regulating processes or operations for pouring responsive to molten metal level or slag level by using electric, magnetic, sonic or ultrasonic means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D2/00—Arrangement of indicating or measuring devices, e.g. for temperature or viscosity of the fused mass
Description
【発明の詳細な説明】
この発明は鋼の連続鋳造に使用される取鍋の如
く、底部に溶鋼流出口を設けた取鍋内の溶鋼残量
を推定する方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for estimating the remaining amount of molten steel in a ladle having a molten steel outlet at the bottom, such as a ladle used in continuous steel casting.
一般に鋼の連続鋳造においては、第１図に示す
ように取鍋１の底部に設けられた溶鋼流出口２に
スライデイングゲート３およびロングノズル４を
取付けておき、取鍋内の溶鋼５を、前記スライデ
イングゲート３およびロングノズル４を経てタン
デイツシユ６に注入し、さらにタンデイツシユ６
内の溶鋼をモールド７に注入して鋳込み、鋳片８
とするのが通常である。 Generally, in continuous steel casting, a sliding gate 3 and a long nozzle 4 are attached to a molten steel outlet 2 provided at the bottom of a ladle 1, as shown in FIG. It is injected into the tundish 6 through the sliding gate 3 and the long nozzle 4, and further into the tundish 6.
The molten steel inside is injected into the mold 7 and cast into slab 8.
This is usually the case.
上述のような鋼の連続鋳造においては、取鍋１
内の溶鋼がなくなれば、別の取鍋と交換して連続
鋳造を継続する。しかるに取鍋１内の溶鋼５の湯
面にはスラグ９が存在し、取鍋内溶鋼の流出末期
にはスラグも流出を開始するから、取鍋内の溶鋼
が完全になくなつてからスライデイングゲート３
を閉じれば、取鍋内のスラグ９もタンデイツシユ
６内に流入してモールド７を通じ鋳片８内に侵入
し、鋳片の内部欠陥の原因となるおそれがある。 In continuous steel casting as described above, ladle 1
When the molten steel in the ladle runs out, it is replaced with another ladle and continuous casting continues. However, slag 9 exists on the surface of the molten steel 5 in the ladle 1, and the slag also starts to flow out at the end of the flow of the molten steel in the ladle, so sliding cannot be started until the molten steel in the ladle is completely gone. gate 3
If the ladle is closed, the slag 9 in the ladle may also flow into the tundish 6 and enter the slab 8 through the mold 7, causing internal defects in the slab.
そこで従来一般には取鍋内の溶鋼残量が少なく
なつたことを操作員が経験的に判別してスライデ
イングゲート３を閉じることにより取鍋内スラグ
の流出を防ぐことが行なわれていた。しかしなが
ら実際には取鍋内の溶鋼量は目視し得ないから、
取鍋中の溶鋼が少なくなつたことは、現実には取
鍋内のスラグ９がロングノズル４を通じてタンデ
イツシユ６内に侵入し始めた時点以降でなければ
判断できない。そのため上述のような経験に頼つ
た操業においては、スラグがタンデイツシユ６内
に流入して結果的に鋳片の内部欠陥をもたらすこ
とを殆んど避け得なかつたのが実情である。さら
に実際の取鍋内においては溶鋼とスラグとが完全
に分離しているわけではなく、ある程度混合状態
にあるから、鋳片の品質を良好に保つためには、
取鍋サイズや品質要求に応じて１〜20トン程度の
範囲で溶鋼を取鍋中に残したままスライデイング
ゲートを閉じる必要がある。 Conventionally, therefore, an operator has determined empirically that the remaining amount of molten steel in the ladle has become low and closed the sliding gate 3 to prevent the slag from flowing out of the ladle. However, in reality, the amount of molten steel in the ladle cannot be visually observed.
In reality, it cannot be determined that the amount of molten steel in the ladle has decreased until after the slag 9 in the ladle begins to enter the tundish 6 through the long nozzle 4. Therefore, in the operation based on experience as described above, it is almost impossible to avoid slag flowing into the tundish 6 and resulting in internal defects in the slab. Furthermore, in the actual ladle, the molten steel and slag are not completely separated, but are mixed to some extent, so in order to maintain good quality of the slab,
Depending on ladle size and quality requirements, it is necessary to close the sliding gate while leaving molten steel in the ladle in a range of 1 to 20 tons.
そこで従来から何らかのデータに基いて取鍋内
の溶鋼残量を推定し、その推定した溶鋼残留量に
基いてスライデイングゲートを閉じる方法が考え
られており、またその方法を実施するために取鍋
内溶鋼残留量を推定する方法が従来からいくつか
提案されている。しかしながら従来提案されてい
る取鍋内溶鋼残量推定方法は、いずれも精度が低
く、実用化するには不充分なものであつた。 Therefore, a method of estimating the amount of molten steel remaining in the ladle based on some data and closing the sliding gate based on the estimated amount of molten steel remaining has been considered. Several methods have been proposed for estimating the residual amount of internally molten steel. However, all of the conventionally proposed methods for estimating the remaining amount of molten steel in the ladle have low accuracy and are insufficient for practical use.
すなわち従来の取鍋内溶鋼残量推定方法として
は、先ず第１には、溶鋼精錬工程における溶鋼の
取鍋ごとの生産量の推定値を基準とし、実績鋳造
量を差し引いて取鍋内の溶鋼残量を算出する方法
が提案されているが、この場合、実際には精錬工
程での溶鋼生産量のばらつきが大きいため、取鍋
内溶鋼量推定値の精度も低くならざるを得ない。 In other words, as a conventional method for estimating the amount of molten steel remaining in the ladle, first, the estimated value of the production amount of molten steel for each ladle in the molten steel refining process is used as a standard, and the actual casting amount is subtracted to estimate the amount of molten steel in the ladle. A method of calculating the remaining amount has been proposed, but in this case, the accuracy of the estimated value of the amount of molten steel in the ladle is inevitably low because the amount of molten steel produced in the refining process actually varies widely.
また第２の方法として、クレーン秤量器により
取鍋を秤量し、空の状態での取鍋重量を差し引い
て取鍋内の初期溶鋼量を算出し、その量から実績
鋳造量を差し引いて取鍋内溶鋼残量を推定する方
法がある。しかながら取鍋内には溶鋼のほか相当
量のスラグが存在し、そのためこの方法の場合ス
ラグの分だけ誤差が生じる。またスラグ量を推定
してその分を差し引くことも考えられるが、スラ
グ量は操業上のばらつきが大きく、正確な推定は
困難である。 The second method is to weigh the ladle with a crane weigher, subtract the weight of the empty ladle to calculate the initial amount of molten steel in the ladle, and subtract the actual casting amount from that amount to calculate the amount of molten steel in the ladle. There is a method to estimate the amount of internal molten steel remaining. However, in addition to the molten steel, there is a considerable amount of slag in the ladle, and therefore, in this method, an error occurs due to the amount of slag. It is also possible to estimate the amount of slag and subtract it, but the amount of slag varies widely during operation, and accurate estimation is difficult.
第３の方法としては、第２図に示すように取鍋
１に上方に距離センサ１０を設置して溶鋼５の湯
面レベル１１を検出し、溶鋼量を算出する方法が
ある。しかしながら溶鋼５の上面にはスラグ９が
存在するため、この方法の場合湯面レベル１１を
正しく検出できないことが多い。また仮にスラグ
層を透過できるような電磁波を距離センサ１０に
用いて湯面レベル１１を正しく検出できたとして
も、取鍋耐火物の溶損の影響によつて溶鋼量の推
定精度が低下する。すなわち取鍋耐火物の溶損が
進行すれば取鍋内容積が大きくなつて、同じ湯面
レベルでも溶鋼量が大きくなり、したがつて実際
の溶鋼量との誤差が大きくなる。 A third method is to install a distance sensor 10 above the ladle 1 to detect the level 11 of the molten steel 5, as shown in FIG. 2, and calculate the amount of molten steel. However, since slag 9 is present on the upper surface of the molten steel 5, the molten metal level 11 cannot often be detected correctly in this method. Furthermore, even if the distance sensor 10 uses electromagnetic waves that can pass through the slag layer to accurately detect the hot water level 11, the accuracy of estimating the amount of molten steel will decrease due to the effects of melting and loss of the ladle refractory. That is, as the ladle refractory progresses, the inner volume of the ladle increases, and even at the same molten metal level, the amount of molten steel increases, and therefore the error from the actual amount of molten steel increases.
以上のように従来の取鍋内溶鋼残量推定方法は
いずれも実際の溶鋼量に対する誤差が大きく、そ
のため従来の推定方法を用いてスライデイングゲ
ートの閉止タイミングをとる場合には、安全サイ
ドを見積つて多目の残留量でスライデイングゲー
トを閉じざるを得ず、したがつてスクラツプとな
る量が多く、コスト高となる問題があつた。 As mentioned above, all of the conventional estimation methods for estimating the remaining amount of molten steel in the ladle have large errors in relation to the actual amount of molten steel. Therefore, when determining the closing timing of the sliding gate using the conventional estimation method, it is necessary to estimate on the safe side. As a result, the sliding gate had to be closed with a large amount remaining, resulting in a large amount of scrap, resulting in a problem of high costs.
この発明は以上の事情に鑑みてなされたもの
で、取鍋内のスラグの量や取鍋耐火物の溶損量に
無関係に取鍋内の溶鋼量を高精度で推定する方法
を提供することを目的とするものである。 This invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for estimating the amount of molten steel in a ladle with high accuracy, regardless of the amount of slag in the ladle or the amount of erosion of the ladle refractories. The purpose is to
すなわちこの発明の方法は、底部に溶鋼流出口
が設けられた取鍋内の溶鋼残量を推定するにあた
り、取鍋の相対する壁面の耐火物に、取鍋内の溶
鋼の湯面レベルの変動に対応するように上下方向
にある幅をもつて励磁コイルおよび磁界検出コイ
ルを同一レベルに対向配置しておき、励磁コイル
から誘起される磁界の強度を検出コイルで測定し
て、取鍋内溶鋼の流出過程における誘起磁界強度
の少なくとも２つの変化点を検出し、それらの変
化点のうち第１の変化点から第２の変化点までの
取鍋内溶鋼流出量を測定もしくは演算により求め
るとともに第２の変化点における残鋼量を求め、
その求められた流出量および残鋼量から第１の変
化点における溶鋼量を定めておき、次回の測定時
においては前記第１の変化点を検知してその第１
の変化点における前記溶鋼量を基準として取鍋内
溶鋼残量を推定することを特徴とするものであ
る。ここで、取鍋内溶鋼の流出過程における誘起
磁界強度の少なくとも２つの変化点とは、湯面レ
ベルがコイル上端位置に対応する時点での誘起磁
界強度の変化点、湯面レベルがコイル下端位置に
対応する時点での誘起磁界強度の変化点、および
湯面レベルが取鍋内の下限位置に達した時点での
誘起磁界温度の変化点、以上３つの変化点のうち
少なくとも２つの変化点を指称するものとする。
そして第１の変化点とは、これらの変化点のうち
相対的に湯面レベルが高い位置での変化点、第２
の変化点とは相対的に湯面レベルが低い位置での
変化点を意味する。このように取鍋の壁面に配置
した励磁コイルの誘起磁界をその励磁コイルに対
し対向配置した検出コイルで測定して誘起磁界の
変化点を検知し、その変化点を基準位置として溶
鋼残量を推定すれば、その変化点はスラグの存
在、スラグの量にほとんど影響を受けないため、
スラグの影響による誤差を招くことなく、高精度
で溶鋼残量を推定することができる。また第１の
変化点における溶鋼量を次回の基準量として用い
るに際して、炉壁耐火物の取鍋１回使用時の溶損
量でその基準溶鋼量を補正すれば、溶損の影響を
ほとんど受けることなく溶鋼残量を推定すること
ができるのである。 In other words, in estimating the remaining amount of molten steel in a ladle with a molten steel outlet provided at the bottom, the method of the present invention measures changes in the level of molten steel in the ladle on refractories on opposing walls of the ladle. An excitation coil and a magnetic field detection coil are arranged facing each other at the same level with a certain width in the vertical direction corresponding to the molten steel in the ladle. Detect at least two changing points in the induced magnetic field strength during the outflow process, measure or calculate the amount of molten steel flowing into the ladle from the first changing point to the second changing point, and Find the amount of remaining steel at the change point of 2,
The amount of molten steel at the first change point is determined from the obtained outflow amount and remaining steel amount, and the first change point is detected during the next measurement.
The remaining amount of molten steel in the ladle is estimated based on the amount of molten steel at the change point. Here, the at least two points of change in the induced magnetic field strength during the outflow process of molten steel in the ladle are the change point in the induced magnetic field strength at the time when the molten metal level corresponds to the upper end position of the coil, and the change point when the molten metal level corresponds to the lower end position of the coil. The change point of the induced magnetic field strength at the time corresponding to , and the change point of the induced magnetic field temperature when the hot water level reaches the lower limit position in the ladle, at least two of the above three change points. shall be designated.
The first change point is a change point at a position where the hot water surface level is relatively high among these change points, and the second change point is a change point at a position where the hot water surface level is relatively high.
The change point means the change point at a position where the hot water level is relatively low. In this way, the induced magnetic field of the excitation coil placed on the wall of the ladle is measured by the detection coil placed opposite to the excitation coil, the change point of the induced magnetic field is detected, and the remaining amount of molten steel is determined using the change point as a reference position. If we estimate, the change point is almost unaffected by the presence of slag and the amount of slag,
The remaining amount of molten steel can be estimated with high accuracy without causing errors due to the influence of slag. In addition, when using the amount of molten steel at the first change point as the next reference amount, if the standard amount of molten steel is corrected by the amount of melting loss when the ladle of the furnace wall refractory is used once, the influence of melting loss is almost eliminated. It is possible to estimate the remaining amount of molten steel without any trouble.
以下にこの発明の推定方法について第３図以降
の図面を参照して詳細に説明する。 The estimation method of the present invention will be explained in detail below with reference to the drawings from FIG. 3 onwards.
第３図はこの発明の方法を実施する状態の一例
を示すものであつて、鉄皮１２に炉壁耐火物１３
を内張りしてなる取鍋１の炉壁耐火物１３中に
は、相互に相対する位置に励磁コイル１４および
検出コイル１５が対向状に埋込まれている。なお
ここで励磁コイル１４および検出コイル１５は、
取鍋１内の溶鋼５の湯面レベルの変動に対応する
ように上下方向にある幅をもつて配置されてお
り、また両コイル１４，１５は同じレベルの位置
に配置されている。励磁コイル１４には、交流励
磁電流発生器１６から供給された交流励磁電流が
流れ、取鍋１内に交流磁界を誘起させる。一方検
出コイル１５は、前記励磁コイル１４により誘起
された磁界の検出コイル位置における磁界強度を
起電力として検出する。 FIG. 3 shows an example of a state in which the method of the present invention is carried out, in which a furnace wall refractory 13 is attached to an iron shell 12.
An excitation coil 14 and a detection coil 15 are embedded in opposing positions in the furnace wall refractory 13 of the ladle 1 lined with . Note that the excitation coil 14 and the detection coil 15 are as follows:
The coils 14 and 15 are arranged with a certain width in the vertical direction so as to correspond to fluctuations in the level of the molten steel 5 in the ladle 1, and both coils 14 and 15 are arranged at the same level. An AC excitation current supplied from an AC excitation current generator 16 flows through the excitation coil 14 to induce an AC magnetic field within the ladle 1 . On the other hand, the detection coil 15 detects the magnetic field intensity at the detection coil position of the magnetic field induced by the excitation coil 14 as an electromotive force.
ここで、励磁コイル１４により取鍋１内に誘起
された磁界の分布は、取鍋内の溶鋼５の影響を強
く受ける。一方スラグ９も磁界分布に対し若干の
影響を与えるが、溶鋼５の影響に比較すれば格段
に少なく、したがつて取鍋内の磁界分布はスラグ
９が存在しない溶鋼５のみの場合と実質的に同様
の磁界分布となる。このように取鍋１内の磁界分
布は溶鋼５の影響を受け、その溶鋼５の湯面レベ
ル１１によつて検出コイル１５が検出する磁界強
度が変化する。 Here, the distribution of the magnetic field induced in the ladle 1 by the excitation coil 14 is strongly influenced by the molten steel 5 in the ladle. On the other hand, the slag 9 also has a slight influence on the magnetic field distribution, but it is much smaller than the influence of the molten steel 5. Therefore, the magnetic field distribution in the ladle is substantially the same as when there is only the molten steel 5 without the slag 9. The magnetic field distribution will be similar to that of . In this way, the magnetic field distribution within the ladle 1 is influenced by the molten steel 5, and the magnetic field strength detected by the detection coil 15 changes depending on the molten metal level 11 of the molten steel 5.
検出コイル１５によつて検出される磁界強度の
変化を、取鍋内溶鋼５の排出に伴なう湯面レベル
１１の変化と対応して第４図Ａ〜Ｄに示す。なお
第４図Ａ〜Ｄにおいて、検出コイル１５により検
出される磁界強度による起電力を電圧計１７の指
針で示す。またここで励磁コイル１４と検出コイ
ル１５の上端同士は同じレベルにあり、また下端
同士も同じレベルにあるものとする。 Changes in the magnetic field strength detected by the detection coil 15 are shown in FIGS. 4A to 4D in correspondence with changes in the hot water level 11 as the molten steel 5 in the ladle is discharged. In addition, in FIGS. 4A to 4D, the electromotive force due to the magnetic field strength detected by the detection coil 15 is indicated by the pointer of the voltmeter 17. It is also assumed here that the upper ends of the excitation coil 14 and the detection coil 15 are at the same level, and the lower ends are also at the same level.
第４図Ａに示すように湯面レベル１１がコイル
１４，１５の上端よりも上方にある場合には、コ
イル１４，１５の間が溶鋼５によつて完全に遮断
されるため、検出コイル１５が検出する磁界強度
は小さい。すなわち励磁コイル１５からの直接の
磁束（１次磁界）は検出コイル１５に到達せず、
励磁コイル１４から溶鋼５内に入りかつその溶鋼
５から漏洩した磁束（２次磁界１９）のみが検出
コイル１５に検出されるが、その２次磁界１９は
１次磁界と比較して格段に弱いから、検出コイル
１５による検出磁界強度の絶対レベルは低い。 As shown in FIG. 4A, when the hot water level 11 is above the upper ends of the coils 14 and 15, the molten steel 5 completely blocks the space between the coils 14 and 15, The magnetic field strength detected by is small. That is, the direct magnetic flux (primary magnetic field) from the excitation coil 15 does not reach the detection coil 15,
Only the magnetic flux (secondary magnetic field 19) that enters the molten steel 5 from the excitation coil 14 and leaks from the molten steel 5 is detected by the detection coil 15, but the secondary magnetic field 19 is much weaker than the primary magnetic field. Therefore, the absolute level of the magnetic field strength detected by the detection coil 15 is low.
次に第４図Ｂに示すように湯面レベル１１がコ
イル１４，１５の上端よりも下方に下がつた場合
（但しコイル１４，１５の下端よりは上方）に
は、励磁コイル１４からの１次磁界１８の一部が
検出コイル１５によつて検出されるようになる。
そして湯面レベル１１が下がるほど、励磁コイル
１４からの１次磁界強度は大きくなるから、湯面
レベル１１の低下に伴つて検出コイル１５の検出
磁界強度は高くなる。なおこの過程では励磁コイ
ル１４から溶鋼５を介しての２次磁界１９も検出
コイル１５によつて検出される。 Next, as shown in FIG. 4B, when the hot water level 11 falls below the upper ends of the coils 14 and 15 (but above the lower ends of the coils 14 and 15), the A portion of the magnetic field 18 then becomes detected by the detection coil 15.
Since the primary magnetic field strength from the excitation coil 14 increases as the hot water level 11 decreases, the detected magnetic field strength of the detection coil 15 increases as the hot water level 11 decreases. In this process, the secondary magnetic field 19 from the excitation coil 14 via the molten steel 5 is also detected by the detection coil 15.
このようにして、第４図Ｃに示すように湯面レ
ベル１１がコイル１４，１５の下端のレベルと同
じレベルとなつた時点で１次磁界強度が最大とな
り、その後第４図Ｄに示す如く湯面レベル１１が
コイル１４，１５の下端よりも下がれば、１次磁
界強度は不変であるが、溶鋼が励磁コイル１４お
よび検出コイル１５の双方から離れることによつ
て、２次磁界強度が次第に低下して行く。したが
つて第４図Ｃに示すように湯面レベル１１がコイ
ル１４，１５の下端に至つた時点で検出コイル１
５による検出磁界強度（起電力）が最大となり、
その後は検出磁界強度は次第に低下することにな
る。そして取鍋１内の溶鋼がなくなれば、それ以
上検出コイル１５による検出磁界強度（起電力）
は低下しない。 In this way, the primary magnetic field strength reaches its maximum when the hot water level 11 reaches the same level as the lower end of the coils 14 and 15, as shown in FIG. 4C, and then as shown in FIG. 4D. When the melt level 11 falls below the lower ends of the coils 14 and 15, the primary magnetic field strength remains unchanged, but as the molten steel moves away from both the excitation coil 14 and the detection coil 15, the secondary magnetic field strength gradually increases. It goes down. Therefore, as shown in FIG. 4C, when the hot water level 11 reaches the lower end of the coils 14 and 15, the detection coil 1
The detected magnetic field strength (electromotive force) by 5 becomes maximum,
After that, the detected magnetic field strength will gradually decrease. When there is no more molten steel in the ladle 1, the magnetic field strength (electromotive force) detected by the detection coil 15 is increased.
does not decrease.
以上のような湯面レベル１１と検出コイル１５
の検出磁界強度との関係をまとめれば、第５図の
ように表わせる。第５図において横軸は検出コイ
ル１５の検出磁界強度（起電力）をあらわし、縦
軸は溶鋼５の湯面レベル１１をコイル１４，１５
の位置と対応してあらわす。 The hot water level 11 and detection coil 15 as described above
The relationship between the detected magnetic field strength and the detected magnetic field strength can be summarized as shown in FIG. In FIG. 5, the horizontal axis represents the detected magnetic field strength (electromotive force) of the detection coil 15, and the vertical axis represents the level 11 of the molten steel 5 in the coils 14, 15.
It is expressed in correspondence with the position of.
第５図からも明らかなように、湯面レベル１１
がコイル１４，１５の上端よりも上方にある状態
からコイル１４，１５の上端に達するまでの間は
検出コイル１５の起電力はほぼ一定の低いレベル
にあり、湯面レベル１１がコイル１４，１５の上
端に達した時点（これを時点Ａとする）からコイ
ル１４，１５の下端に達するまでは検出コイル１
５の起電力が急激に増大し、コイル１４，１５の
下端に達した時点（これを時点Ｂとする）で起電
力が最大となる。そして時点Ｂ以降は、湯面レベ
ル１１が炉底に達した時点すなわち取鍋１内の溶
鋼５がなくなつた時点（これを時点Ｃとする）ま
で起電力がゆるやかに減少する。したがつて検出
コイル１５の起電力の変化は、時点Ａ，Ｂ，Ｃの
３点で顕著にとらえることができる。そしてまた
時点Ａ，Ｂはコイル１４，１５と溶鋼５の湯面レ
ベル１１との位置関係によつて定まるから、スラ
グ９の存在や耐火物の溶損とは無関係に、常に一
定の位置に対応することになる。また時点Ｃは溶
鋼がなくなつた時点であるから、これもスラグや
耐火物の溶損とは無関係に一定の位置に対応する
ことになる。 As is clear from Figure 5, the hot water level is 11.
The electromotive force of the detection coil 15 is at an almost constant low level from the state where it is above the upper end of the coils 14, 15 until it reaches the upper end of the coils 14, 15, and the electromotive force of the detection coil 15 is at a substantially constant low level. From the time when the upper end is reached (this is referred to as time A) until the lower end of the coils 14 and 15 is reached, the detection coil 1
The electromotive force at No. 5 increases rapidly, and reaches its maximum when it reaches the lower ends of the coils 14 and 15 (this is referred to as time B). After time B, the electromotive force gradually decreases until the melt level 11 reaches the bottom of the furnace, that is, the molten steel 5 in the ladle 1 is exhausted (this is referred to as time C). Therefore, changes in the electromotive force of the detection coil 15 can be clearly detected at three points, A, B, and C. Furthermore, since points A and B are determined by the positional relationship between the coils 14 and 15 and the molten steel level 11 of the molten steel 5, they always correspond to fixed positions regardless of the presence of the slag 9 or the melting loss of the refractory. I will do it. Moreover, since time C is the time when the molten steel is gone, this also corresponds to a fixed position regardless of the melting loss of slag and refractories.
そこでこの発明の方法では、最初の測定時にお
いて時点Ａ，Ｂ，Ｃのうち少なくとも２つの変化
点（例えばＢ，Ｃ）を検出し、その検出した変化
点のうち、湯面レベルが高い方の変化点（例えば
Ｂ）から湯面レベルが低い方の変化点（例えば
Ｃ）に達するまでの溶鋼流出量を実績鋳造量等か
ら推定もしくは演算するとともに、湯面レベルが
低い方の変化点Ｃにおける残鋼量を求め、これら
の値から湯面レベルが高い方の変化点Ｂにおける
溶鋼量を求める。そして次回の測定時において
は、前回の測定時に溶鋼量を求めた変化点Ｂを検
出し、その変化点Ｂを基準としてその変化点Ｂ以
降の取鍋内落鋼量を実績鋳造量等から推定する。 Therefore, in the method of the present invention, at least two change points (for example, B and C) among time points A, B, and C are detected during the first measurement, and among the detected change points, the one where the hot water surface level is higher is detected. Estimate or calculate the flow rate of molten steel from the change point (e.g. B) to the change point (e.g. C) where the surface level is lower than the change point (e.g. C) based on the actual casting amount, etc. The amount of remaining steel is determined, and from these values, the amount of molten steel at the change point B where the molten metal level is higher is determined. Then, during the next measurement, detect the change point B where the amount of molten steel was determined during the previous measurement, and use that change point B as a reference and estimate the amount of steel falling in the ladle after that change point B from the actual casting amount, etc. do.
ここで説明の簡略化のために最初の測定時にお
いて時点Ｂ，Ｃの変化点を検出する例について次
に説明する。 To simplify the explanation, an example will be described below in which the changing points at time points B and C are detected during the first measurement.
取鍋１からの溶鋼流出過程において前述のよう
に検出コイル１５によつて磁界強度を測定し、そ
の検出コイル１５の起電力のデータを演算器２０
に入力させ、起電力が最大となつた時点を変化点
Ｂとして検出する。さらに取鍋１からの流出が進
んで、取鍋１内の溶鋼５がなくなつた時点を変化
点Ｃとして検出し、その変化点Ｃにおける起電力
Voを記憶させておく。このような検出と同時ま
たは検出後に、変化点ＢからＣに至るまでの間の
溶鋼流出量を求める。この溶鋼流出量は、変化点
ＡからＣに至るまでの間の連続鋳造の鋳造速度を
積分することによつて得ることができる。ここ
で、変化点Ｃにおける残鋼量は零であるから、上
述のようにして求められた変化点Ｂ〜Ｃ間の溶鋼
流出量が変化点Ｂにおける取鍋内溶鋼量に相当す
ることになる。そこでこの変化点Ｂにおける溶鋼
量を次回の測定のために演算器２０に記憶させて
おく。 During the process of molten steel flowing out from the ladle 1, the magnetic field strength is measured by the detection coil 15 as described above, and the electromotive force data of the detection coil 15 is sent to the calculator 20.
is input, and the point of time when the electromotive force reaches its maximum is detected as the change point B. The point at which the molten steel 5 in the ladle 1 disappears as the flow from the ladle 1 further progresses is detected as a change point C, and the electromotive force at that change point C is detected.
Memorize Vo. Simultaneously with or after such detection, the flow rate of molten steel from change point B to C is determined. This flow rate of molten steel can be obtained by integrating the casting speed of continuous casting from change point A to C. Here, since the amount of remaining steel at change point C is zero, the amount of molten steel flowing out between change points B and C obtained as described above corresponds to the amount of molten steel in the ladle at change point B. . Therefore, the amount of molten steel at this change point B is stored in the calculator 20 for the next measurement.
次回の測定にあたつては、前回の測定時に求め
られた変化点Ｂでの溶鋼量を推定基準値としてそ
のまま用いても良いが、耐火物の溶損による推定
誤差を少なくするためには、取鍋の１回の使用に
よる耐火物溶損量を予め調べておき、その耐火物
溶損により取鍋１の内容積が増加した分の量を補
正値として加えた溶鋼量を次回測定時の変化点Ｂ
の推定基準値とすることが望ましい。この測定時
においては、前回の測定時と同時に検出コイル１
５によつて磁界強度を測定し、検出コイル１５の
起電力が最大となつた時点（変化点B′）を検出す
る。この変化点B′における湯面レベルは前回の測
定時の変化点Ｂにおける湯面レベルと同じである
から、変化点B′における溶鋼量の推定値として、
前述の如く前回の測定時における変化点Ｂの溶鋼
量を溶損量で補正した値を用いる。そしてその変
化点B′以降においては、変化点B′での推定値に対
し、実時間で鋳造速度を積分して減算し、実時間
における溶鋼量を算出する。このようにすること
によつて、変化点B′以降の取鍋内溶鋼量が実時間
で推定されるから、例えば連続鋳造機の取鍋にお
いては、その推定溶鋼量が取鍋サイズや品質要求
等に応じて予め定めた残留させるべき量に達した
時点でスライデイングゲートを閉じれば良い。 For the next measurement, the amount of molten steel at change point B obtained during the previous measurement may be used as is as the estimated reference value, but in order to reduce the estimation error due to melting of the refractory, The amount of refractory erosion due to one use of the ladle is investigated in advance, and the amount of molten steel added as a correction value to the amount of increase in the internal volume of ladle 1 due to the refractory erosion is calculated for the next measurement. Change point B
It is desirable to use this as the estimated reference value. During this measurement, at the same time as the previous measurement, the detection coil 1
5, the magnetic field strength is measured, and the point in time when the electromotive force of the detection coil 15 reaches its maximum (change point B') is detected. Since the melt level at this change point B' is the same as the melt level at change point B during the previous measurement, the estimated value of the amount of molten steel at change point B' is:
As mentioned above, a value obtained by correcting the amount of molten steel at the change point B in the previous measurement by the amount of melting loss is used. After the change point B', the casting speed is integrated in real time and subtracted from the estimated value at the change point B' to calculate the amount of molten steel in real time. By doing this, the amount of molten steel in the ladle after the change point B' can be estimated in real time. The sliding gate may be closed when a predetermined amount to be left remains is reached.
以上の例は、変化点Ｂ，Ｃを検出して、次回の
測定時には変化点Ｂに対応する時点の推定溶鋼量
を基準としたが、変化点Ａ，Ｃあるいは変化点
Ａ，Ｂを検出して、次回の測定時に変化点Ａに対
応する時点の推定溶鋼量を基準としても良いこと
は勿論である。 In the above example, change points B and C were detected, and the next measurement was based on the estimated amount of molten steel at the time corresponding to change point B, but change points A and C or change points A and B were detected. Of course, the estimated amount of molten steel at the time corresponding to the change point A may be used as a reference for the next measurement.
なおこの発明の方法は、連続鋳造における取鍋
に限らず、要は底部に溶鋼流出口が設けられた取
鍋内の溶鋼残量推定に全て適用できることは勿論
である。 It goes without saying that the method of the present invention is applicable not only to ladles in continuous casting, but also to any estimation of the remaining amount of molten steel in a ladle having a molten steel outlet at the bottom.
以下にこの発明の方法による実験結果を記す。 The experimental results obtained using the method of this invention are described below.
この発明の推定方法による精度秤価を行うた
め、この発明の方法による取鍋内推定溶鋼量が
２、４、６、８、10、12トンになつた時点でスラ
イデイングゲートを閉じ、取鍋内のスラグおよび
溶鋼を分離して冷却凝固させた後、鋼塊のみを秤
量して、溶鋼の実際の取鍋内残量を測定した。こ
の実験の結果を第６図に示す。第６図によれば、
実際の溶鋼量に対する推定量の誤差はほぼ１トン
程度であり、前述した従来方法では最も高精度の
場合でも誤差が３トン程度あつたのに対し、この
発明の推定方法によれば格段の精度向上を達成し
得たことが明らかである。 In order to perform precision weighing using the estimation method of this invention, the sliding gate is closed when the estimated amount of molten steel in the ladle reaches 2, 4, 6, 8, 10, and 12 tons using the method of this invention. After separating the slag and molten steel inside the ladle and solidifying them by cooling, only the steel ingot was weighed to measure the actual amount of molten steel remaining in the ladle. The results of this experiment are shown in FIG. According to Figure 6,
The error in the estimated amount relative to the actual amount of molten steel is about 1 ton, and while the conventional method described above had an error of about 3 tons even in the most accurate case, the estimation method of the present invention has much higher accuracy. It is clear that improvements have been achieved.
さらにこの発明の方法を連続的鋳造における実
操業に適用してスライデイングゲートの閉止タイ
ミング制御を行なつた効果を第６図に示す。第６
図は鋼材内部品質要求の強いある鋼種の連続鋳造
におけるスライデイングゲート閉止タイミング制
御にこの発明の方法を適用した場合、およびこの
発明の方法を適用せずに経験的にゲート閉止を行
なつた場合の、鋳片の不良率を比較して示すもの
である。この発明を方法に適用しない場合には、
取鍋中のスラグがタンデイツシユに流出し、ひい
ては鋳片に非金属介在物として残留して不良とな
るケースが多かつた。これに対しこの発明の方法
を適用した後には、上記のケースは皆無となり、
別要因での若干の不良のみとなつて鋼材の品質向
上、歩留り向上に大きく貢献されることが確認さ
れた。 Further, FIG. 6 shows the effect of controlling the closing timing of the sliding gate by applying the method of the present invention to an actual continuous casting operation. 6th
The figure shows a case where the method of the present invention is applied to the sliding gate closing timing control in continuous casting of a steel type with strong internal quality requirements, and a case where the gate is closed empirically without applying the method of the present invention. This figure shows a comparison of the defective rates of slabs. If this invention is not applied to the method,
There were many cases in which the slag in the ladle flowed into the tundish and eventually remained in the slab as non-metallic inclusions, resulting in defects. On the other hand, after applying the method of this invention, the above cases will disappear.
It was confirmed that this method greatly contributed to improving the quality and yield of steel materials, with only a few defects caused by other factors.
以上の説明で明らかなようにこの発明の取鍋残
溶鋼量推定方法によれば、取鍋内の溶鋼残量を、
溶鋼湯面上のスラグの影響を受けることなく、実
時間で高精度に推定することができ、したがつて
例えば連続鋳造設備における取鍋のスライデイン
グゲートの閉止タイミング制御にこの発明の方法
を適用すれば、スラグの流出を確実に防止して高
品質の鋳片を得ることができると同時に、スライ
デイングゲート閉止後に過剰な量の溶鋼を取鍋内
に残すことを防止して、稼働率の向上を図ること
ができる。そしてまた特に取鍋壁面の耐火物の推
定溶損量によつて補正する実施態様によれば、耐
火物の溶損の影響による推定誤差を小さくして、
より一層高精度での溶鋼量推定が可能となる。 As is clear from the above explanation, according to the method for estimating the amount of molten steel remaining in the ladle of the present invention, the amount of molten steel remaining in the ladle can be calculated by
The method of the present invention can be estimated with high precision in real time without being affected by slag on the surface of molten steel. Therefore, the method of the present invention can be applied, for example, to control the closing timing of a sliding gate of a ladle in continuous casting equipment. By doing so, you can reliably prevent slag from flowing out and obtain high-quality slabs, and at the same time, prevent an excessive amount of molten steel from remaining in the ladle after closing the sliding gate, thereby improving the operating rate. You can improve your performance. In addition, according to an embodiment in which correction is performed based on the estimated amount of erosion of the refractory on the wall surface of the ladle, the estimation error due to the influence of erosion of the refractory is reduced,
It becomes possible to estimate the amount of molten steel with even higher accuracy.
第１図はこの発明の方法を適用する対象となる
連続鋳造設備の一般的な例を模式的に示す略解
図、第２図は従来の推定方法の一例を実施してい
る状況を示す略解図である。第３図はこの発明の
方法を実施している状況の一例を示す略解図、第
４図Ａ〜Ｄはこの発明の方法を実施する際におけ
る取鍋内溶鋼湯面レベルと検出コイルの検出磁界
強度（起電力）の関係を段階的に示す略解図、第
５図は同じく湯面レベルと検出コイルの検出磁界
強度（起電力）との関係を示す線図、第６図はこ
の発明の方法により推定された取鍋残溶鋼量の精
度を示すための線図、第７図はこの発明の方法を
連続鋳造設備のスライデイングゲート閉止タイミ
ング制御に適用した場合の鋳片不良率を、この発
明の方法を適用しなかつた場合と比較して示す線
図である。
１……取鍋、２……溶鋼流出口、３……スライ
デイングゲート、５……溶鋼、９……スラグ、１
４……励磁コイル、１５……検出コイル、Ａ，
Ｂ，Ｃ……変化点。
Fig. 1 is a schematic diagram schematically showing a general example of continuous casting equipment to which the method of the present invention is applied, and Fig. 2 is a schematic diagram showing a situation in which an example of the conventional estimation method is implemented. It is. Fig. 3 is a schematic diagram showing an example of a situation in which the method of the present invention is carried out, and Figs. 4 A to D show the level of the molten steel in the ladle and the detection magnetic field of the detection coil when carrying out the method of the present invention. A schematic diagram showing the relationship between the strength (electromotive force) step by step, FIG. 5 is a diagram showing the relationship between the hot water level and the detected magnetic field strength (electromotive force) of the detection coil, and FIG. 6 is a method of the present invention. Figure 7 is a diagram showing the accuracy of the amount of remaining molten steel in the ladle estimated by the method of the present invention, and shows the slab defect rate when the method of the present invention is applied to the sliding gate closing timing control of continuous casting equipment. FIG. 3 is a diagram showing a comparison with a case where the method described above is not applied. 1... Ladle, 2... Molten steel outlet, 3... Sliding gate, 5... Molten steel, 9... Slag, 1
4... Excitation coil, 15... Detection coil, A,
B, C... Change points.
Claims (1)
残量を推定するにあたり、 取鍋の相対する壁面の耐火物中に、取鍋内の溶
鋼の湯面レベルの変動に対応するように上下方向
にある幅をもつて励磁コイルおよび磁界強度検出
コイルを同一レベルに対向配置しておき、励磁コ
イルから誘起される磁界の強度を検出コイルで測
定し、取鍋内溶鋼の流出過程において湯面レベル
がコイル上端位置に対応する時点での誘起磁界強
度の変化点、湯面レベルがコイル下端位置に対応
する時点での誘起磁界強度の変化点、および湯面
レベルが取鍋内の下限位置に至つた時の誘起磁界
強度の変化点のうち、少なくとも２つの変化点を
検出し、それらの変化点のうち第１の変化点から
第２の変化点までの取鍋内溶鋼流出量を測定もし
くは演算により求めるとともに第２の変化点にお
ける残鋼量を求め、その求められた流出量および
残鋼量から第１の変化点における溶鋼量を定めて
おき、次回の測定時においては前記第１の変化点
を検知してその第１の変化点における前記溶鋼量
を基準として取鍋内溶鋼残量を推定することを特
徴とする取鍋残溶鋼量の推定方法。 ２ 前記の次回の測定時に使用する第１の変化点
での溶鋼量として、取鍋内壁耐火物の推定溶損量
で補正した値を用いる特許請求の範囲第１項記載
の取鍋残溶鋼量の推定方法。[Claims] 1. In estimating the remaining amount of molten steel in a ladle with a molten steel outlet provided at the bottom, the level of the molten steel in the ladle is measured in the refractories on the opposing walls of the ladle. An excitation coil and a magnetic field strength detection coil are placed facing each other at the same level with a certain width in the vertical direction to accommodate fluctuations, and the strength of the magnetic field induced from the excitation coil is measured with the detection coil. In the flow process of molten steel, the change point of the induced magnetic field strength at the time when the molten metal level corresponds to the top position of the coil, the change point of the induced magnetic field strength when the molten metal level corresponds to the bottom position of the coil, and the change point of the molten steel surface level. Among the changing points of the induced magnetic field strength when reaching the lower limit position in the ladle, at least two changing points are detected, and the ladle is moved from the first changing point to the second changing point among those changing points. The amount of internal molten steel flowing out is determined by measurement or calculation, and the amount of remaining steel at the second change point is determined, and the amount of molten steel at the first change point is determined from the determined amount of outflow and the amount of remaining steel, and then the next measurement is carried out. A method for estimating a remaining amount of molten steel in a ladle, sometimes comprising detecting the first changing point and estimating the remaining amount of molten steel in the ladle based on the amount of molten steel at the first changing point. 2. The amount of remaining molten steel in the ladle as set forth in claim 1, in which a value corrected by the estimated amount of erosion of the refractories on the inner wall of the ladle is used as the amount of molten steel at the first change point used at the time of the next measurement. estimation method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13272084A JPS619966A (en) | 1984-06-27 | 1984-06-27 | Estimating method of amount of molten steel remaining in ladle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13272084A JPS619966A (en) | 1984-06-27 | 1984-06-27 | Estimating method of amount of molten steel remaining in ladle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS619966A JPS619966A (en) | 1986-01-17 |
| JPS6257427B2 true JPS6257427B2 (en) | 1987-12-01 |
Family
ID=15087999
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13272084A Granted JPS619966A (en) | 1984-06-27 | 1984-06-27 | Estimating method of amount of molten steel remaining in ladle |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS619966A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102004032561B3 (en) | 2004-07-05 | 2006-02-09 | Heraeus Electro-Nite International N.V. | Container for molten metal and use of the container |
| JP6260318B2 (en) * | 2014-02-06 | 2018-01-17 | 株式会社豊田自動織機 | Power storage device manufacturing method and power storage device inspection method |
| CN108515156B (en) * | 2018-04-13 | 2020-01-07 | 东北大学 | Method for measuring ladle casting allowance in continuous casting and pouring process |
| CN108372279B (en) * | 2018-04-13 | 2020-01-07 | 东北大学 | Method for measuring pouring allowance of tundish in continuous casting pouring process |
| IT201800006804A1 (en) * | 2018-06-29 | 2019-12-29 | METAL LEVEL DETECTION DEVICE IN AN ELECTRIC ARC OVEN |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59112230A (en) * | 1982-12-06 | 1984-06-28 | ストウドスビツク・エネルギテクニツク・アクチ−ボラグ | Method and device for measuring molten metal in bottom of vessel |
-
1984
- 1984-06-27 JP JP13272084A patent/JPS619966A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59112230A (en) * | 1982-12-06 | 1984-06-28 | ストウドスビツク・エネルギテクニツク・アクチ−ボラグ | Method and device for measuring molten metal in bottom of vessel |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS619966A (en) | 1986-01-17 |
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