JPH03254345A - Method for controlling measurement of molten steel flow rate - Google Patents
Method for controlling measurement of molten steel flow rateInfo
- Publication number
- JPH03254345A JPH03254345A JP5095090A JP5095090A JPH03254345A JP H03254345 A JPH03254345 A JP H03254345A JP 5095090 A JP5095090 A JP 5095090A JP 5095090 A JP5095090 A JP 5095090A JP H03254345 A JPH03254345 A JP H03254345A
- Authority
- JP
- Japan
- Prior art keywords
- flow rate
- molten steel
- tundish
- coefficient
- nozzle
- 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.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 49
- 239000010959 steel Substances 0.000 title claims abstract description 49
- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000005259 measurement Methods 0.000 title claims abstract description 10
- 241000277275 Oncorhynchus mykiss Species 0.000 claims abstract description 9
- 238000005070 sampling Methods 0.000 claims abstract description 8
- 238000009749 continuous casting Methods 0.000 abstract description 2
- 230000005499 meniscus Effects 0.000 description 8
- 238000002347 injection Methods 0.000 description 5
- 239000007924 injection Substances 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 238000007711 solidification Methods 0.000 description 5
- 230000008023 solidification Effects 0.000 description 5
- 239000007788 liquid Substances 0.000 description 4
- 238000000691 measurement method Methods 0.000 description 4
- 238000005266 casting Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- -1 ferrous metals Chemical class 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Landscapes
- Measuring Volume Flow (AREA)
- Continuous Casting (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野〕
本発明は例えば鉄鋼業においてタンディツシュ等から流
入する溶鋼のノズル流量計測制御技術に関し、鉄鋼業の
みならず流量の接触計測が不可能な溶融非鉄金属等の流
量測定にも応用できる。Detailed Description of the Invention (Industrial Field of Application) The present invention relates to nozzle flow rate measurement and control technology for molten steel flowing from a tundish etc. in the steel industry, for example. It can also be applied to measuring the flow rate of metals, etc.
従来、流量計測ではオリフィスや電磁流量計。 Traditionally, flow measurement has been done using orifices or electromagnetic flowmeters.
渦流量計９面積式流量計、容積式流量計、タービン式流
量計等多くの液体流量計測技術が考えられている。しか
しこれらの流量計測方法は検出部分が直接液体と接する
構造をもつため溶鋼のように高温な液体ではセンサー溶
損等の問題があり計測は不可能であった。また流速測定
法による流量計測では液体粘性による流速分布が原因で
生じる測定誤差が問題としてあり、また電磁流量計にお
いては導管が充満していなければ計測不可能である等、
問題点があった。Many liquid flow rate measurement techniques have been considered, including vortex flowmeters, area flowmeters, positive displacement flowmeters, and turbine flowmeters. However, since these flow rate measurement methods have a structure in which the detection part is in direct contact with the liquid, measurement is impossible with high-temperature liquids such as molten steel due to problems such as sensor erosion. In addition, measurement errors caused by flow velocity distribution due to liquid viscosity are a problem with flow rate measurement using the current velocity measurement method, and with electromagnetic flowmeters, measurement is impossible unless the conduit is full.
There was a problem.
このため本発明ではノズルを流れる溶鋼の流量を計測制
御する技術において、非接触で溶鋼流量を測定し、ノズ
ルの流量係数の同定及び流量の推定制御を実現すること
をｍ題とする。Therefore, in the present invention, in a technology for measuring and controlling the flow rate of molten steel flowing through a nozzle, the problem is to measure the flow rate of molten steel in a non-contact manner, identify the flow coefficient of the nozzle, and realize estimation control of the flow rate.
上記課題を解決するため、本発明においては、溶鋼流量
を非接触で計測することを目標として計測あるいは算出
可能な情報である溶鋼流入面積および溶融ヘッドとタン
ディツシュ重量変化から逐次形最小２乗法により同定し
たノズル流量係数より溶鋼流量を算出し、流量推定値フ
ィードバック制御を行う。In order to solve the above problems, in the present invention, the flow rate of molten steel is identified using the sequential least squares method from the measurable or computable information such as the molten steel inflow area and changes in the weight of the melting head and tundish. The molten steel flow rate is calculated from the calculated nozzle flow coefficient, and the estimated flow rate feedback control is performed.
本発明では推定溶鋼流量ｅの算出とノズルの流量係数Ｃ
を同定するため溶鋼流入面積Ｓ、溶鋼ヘッドｈ、ノズル
流量係数Ｃを以下の手順で計測および算出する。In the present invention, calculation of estimated molten steel flow rate e and nozzle flow coefficient C
In order to identify the molten steel inflow area S, molten steel head h, and nozzle flow coefficient C are measured and calculated according to the following procedure.
作動トランスにより計測したストッパ開度と羽口及びス
トッパ形状より溶鋼がノズルへ流入する面積Ｓ （ｗａ
２）を幾何学的に算出する。この溶鋼流入面積Ｓはスラ
イディングノズル等の溶鋼流入絞り形状を変化させる流
量制御方法においても開度と幾何学的形状が測定できれ
ば溶鋼流入面積Ｓは算出可能である。また、タンディツ
シュに取り付けたロードセル出力よりタンディツシュの
内の溶鋼重量を計測し溶鋼密度およびタンディツシュ内
形状から溶鋼ヘッドｈ（閣）を算出する。この溶鋼ヘッ
ドｈはタンディツシュに取り付けたレベル計により計測
した湯面レベルを用いても計測可能である。The area where molten steel flows into the nozzle S (wa
2) is calculated geometrically. This molten steel inflow area S can be calculated even in a flow rate control method that changes the molten steel inflow throttle shape using a sliding nozzle, etc., if the opening degree and geometrical shape can be measured. In addition, the weight of molten steel in the tundish is measured from the output of a load cell attached to the tundish, and the molten steel head h is calculated from the molten steel density and the shape inside the tundish. The molten steel head h can also be measured using the molten metal level measured by a level meter attached to the tundish.
ノズル形状、ストッパ開度や溶鋼粘性等により変化する
ノズル流量係数Ｃは操業開始時では過去の実験値または
前回の実操業での流量係数初期値を初期操業条件として
設定する。流量係数Ｃの同定方法は以下のように行う。The nozzle flow coefficient C, which changes depending on the nozzle shape, stopper opening, molten steel viscosity, etc., is set as the initial operating condition at the start of operation, using the past experimental value or the initial flow coefficient value from the previous actual operation. The flow coefficient C is identified as follows.
サンプリング時間の設定は時間経過による流量係数の変
動が無視できる程度の適当な時間（例えば１２０ ｓｅ
ｃ ）を設定しタンディッシュに取り付けたロードセル
の出力から求められるサンプリング時間毎の流量実績を
算出する。この流量実績から逐次形最小２乗法を用いて
流量係数Ｃの同定を行い次のサンプリング時間での流量
推定制御系での流量係数Ｃとして制御系に新しく設定し
流量推定フィードバック制御を行う。The sampling time should be set at an appropriate time (for example, 120 se
c)) and calculate the actual flow rate for each sampling time determined from the output of the load cell attached to the tundish. From this flow rate record, the flow rate coefficient C is identified using the sequential least squares method, and a new flow rate coefficient C is set in the control system as the flow rate coefficient C in the flow rate estimation control system at the next sampling time, and flow rate estimation feedback control is performed.
羽口での溶鋼流速Ｖ （ｍ ／ ｓｅｅ ）は、タンデ
ィツシュ内溶鋼ヘッドｈ、ノズル流量係数Ｃより（１〉
式で表わされる。The molten steel flow velocity V (m/see) at the tuyere is determined by the molten steel head h in the tuyere and the nozzle flow coefficient C (1>
It is expressed by the formula.
Ｖ＝ＣＦ７７ｇ ＝ −（１）
ノズルより注入される溶鋼流量Ｑ（ｗ＋’ ／５ｅｅ）
は（２）式で推定できる。V=CF77g = -(1) Flow rate of molten steel injected from the nozzle Q (w+'/5ee)
can be estimated using equation (2).
ｆｒ＝ ｓ −ｖ ・・・（２）但し、
■＝副羽口の溶鋼流速（閣／５ｅｅ）
ｈ：タンディッシュ内溶鋼ヘッド（ｍｍ）Ｃ：流量係数
八
Ｑ：推定溶鋼流量（ｗａ ３／ ５ｅｅ）Ｓ：溶鋼流入
面積（ｍ＝”）
推定流量０および逐次形最小２乗法により同定した流量
係数Ｃを用いて推定流量フィードバック制御を行う。fr = s - v ... (2) However, ■ = Molten steel flow rate in sub-tuyere (Kaku/5ee) h: Molten steel head in tundish (mm) C: Flow coefficient 8Q: Estimated molten steel flow rate (wa 3 /5ee) S: Molten steel inflow area (m='') Estimated flow rate feedback control is performed using the estimated flow rate 0 and the flow coefficient C identified by the successive least squares method.
以下、図面を参照しながら本発明の実施例について説明
する。第１図は複層鋼鋳造における内外層溶鋼流量制御
において本発明の方法（点線内）を適用した具体例を示
したものである。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a specific example in which the method of the present invention (indicated by dotted lines) is applied to control the flow rate of molten steel in the inner and outer layers in multilayer steel casting.
このプロセスでは外層凝固レベルである１次メニスカス
レベル、および内層凝固レベルである２次メニスカスレ
ベルの変動は遷移層の発生等鋳片性状を悪化させる原因
となる。１次メニスカスレベルと２次メニスカスレベル
の可観測性を調べたところ不可観測であり現在の計測技
術では計測不可能であることが解明された。高品質な複
層鋼を安定して鋳造するにはモールド湯面、外Ｗにａａ
固レベルである１次メニスカスレベル、及び内層凝固レ
ベルである２次メニスカスレベルを設定値に収束安定さ
せる必要がある。このため本発明方法である流量計測、
制御方法を適用し内層及び外層溶鋼流量を各々計測し溶
鋼流量の比率を一定に保ちかつ流量和制御によるモール
ド場面レベル制御を行っている。In this process, fluctuations in the primary meniscus level, which is the solidification level of the outer layer, and the secondary meniscus level, which is the solidification level of the inner layer, cause deterioration of the properties of the slab, such as the generation of a transition layer. When we investigated the observability of the primary meniscus level and the secondary meniscus level, we found that they are unobservable and cannot be measured using current measurement technology. To stably cast high-quality multilayer steel, the mold surface and outer W should be aaa.
It is necessary to converge and stabilize the primary meniscus level, which is a solid level, and the secondary meniscus level, which is an inner layer solidification level, to a set value. For this reason, the flow rate measurement method of the present invention,
A control method is applied to measure the flow rate of molten steel in the inner layer and the outer layer, to keep the ratio of the molten steel flow rate constant, and to control the mold scene level by controlling the sum of the flow rates.
内層および外層タンディツシュのストッパ形状および羽
口形状と作動トランスにより測定されたストッパ開度か
ら内外層各々の溶鋼流入面積Ｓを幾何学的に算出してい
る。The molten steel inflow area S of each of the inner and outer layers is calculated geometrically from the stopper shape and tuyere shape of the inner and outer layer tundishes and the stopper opening degree measured by the operating transformer.
また、タンディツシュに取り付けたロードセルにより計
測したタンディツシュ内溶鋼重量と溶鋼密度より溶鋼体
積を算出しタンディツシュ形状より溶鋼ヘッドｈを算出
している。Further, the molten steel volume is calculated from the molten steel weight and molten steel density in the tundish measured by a load cell attached to the tundish, and the molten steel head h is calculated from the tundish shape.
流量係数は過去の実験値および前操業で同定した流量係
数を初期流量係数Ｃとして流量制御系へ設定する。初期
流量係数Ｃにより操業を開始するとともに一定時間間隔
（１２０秒）毎にロードセルによりタンディッシュ重量
変化を測定しこれより流量実積を算出する。この流量実
積から逐次型最小二乗法により流量係数Ｃを同定し次の
サンプリング時間中での流量係数Ｃとして流量制御系へ
設定する。以上の様にして算出および同定された溶鋼流
入面積Ｓ、タンディツシュヘッドｈ、流量係数Ｃを（１
）式および（２）式に代入して推定流量舎の状態フィー
ドバック制御を行っている。The flow coefficient is set to the flow control system using past experimental values and flow coefficients identified in previous operations as the initial flow coefficient C. The operation is started with the initial flow coefficient C, and the change in the weight of the tundish is measured by a load cell at regular time intervals (120 seconds), and the actual flow rate is calculated from this. From this actual flow rate product, a flow coefficient C is identified by the successive least squares method, and is set to the flow control system as the flow coefficient C during the next sampling period. The molten steel inflow area S, tundish head h, and flow coefficient C calculated and identified as described above are (1
) and (2) to perform state feedback control of the estimated flow rate building.
この溶鋼流量計測制御方法により湯面レベルの安定と外
層凝固レベルである１次メニスカスレベル及び内層凝固
レベルである２次メニスカスレベルの設定値への収束が
可能となり内外層の明瞭に分離された鋳片を安定して鋳
造することが可能となった。This method of measuring and controlling the flow rate of molten steel makes it possible to stabilize the molten metal level and converge the primary meniscus level, which is the outer layer solidification level, and the secondary meniscus level, which is the inner layer solidification level, to the set values, so that the inner and outer layers are clearly separated. It became possible to stably cast pieces.
以上述べたように本発明によれば計測不可能であった溶
鋼流量が計測可能となり同時にノズルの流量係数も同定
できるため流量の推定制御が可能となり今まで溶鋼流量
計測が不可能であったため実現不可能であった複層鋼連
続鋳造のようなプロセスが実現し、非鉄金属の温材流量
計測等へも応用できこの効果は計り知れないものがある
。As described above, according to the present invention, the flow rate of molten steel, which was previously impossible to measure, can be measured, and at the same time, the flow coefficient of the nozzle can also be identified, making it possible to estimate and control the flow rate, which was previously impossible to measure. Processes such as continuous continuous casting of multi-layered steel, which were impossible to achieve, have been realized, and the benefits of this technology are immeasurable, as it can be applied to things such as measuring the flow rate of hot materials in non-ferrous metals.
第１図は複層鋼連続鋳造に本発明の方法（焦線枠内）を
適用した制御系のブロック図である。
ｄｒ：内外層目ｍ鋳造比
ｖｒ：目標引き抜き速度（ｆｆＩｌ／５ｅｃ）ｈｒ：目
標湯面レベル（−）
ｑ Ａ ｒ ：目標内層溶鋼注入量（ｎｍ’ ／５ｅｃ
）ｑＢｒ ：目標外層溶鋼注入量（ａｍ” ／５ｅｃ）
ｑＡ：内層注入量（Ｉｍ’ ／５ｅｃ）ｑＢ：外層注入
量（ｍ” ／５ｅｅ）
＾：推定内層注入量（１／５ｅｃ）FIG. 1 is a block diagram of a control system in which the method of the present invention (within the focal line frame) is applied to multilayer continuous steel casting. dr: Inner and outer layer m casting ratio vr: Target drawing speed (ffIl/5ec) hr: Target molten metal level (-) q A r: Target inner layer molten steel injection amount (nm'/5ec)
)qBr: Target outer layer molten steel injection amount (am”/5ec)
qA: Inner layer injection amount (Im'/5ec) qB: Outer layer injection amount (m"/5ee) ^: Estimated inner layer injection amount (1/5ec)
Claims (1)
測制御において溶鋼が流入するストッパー羽口間面積と
タンディッシュでの溶鋼ヘッド、およびタンディッシュ
とレードルのサンプリング時間毎の重量変化から逐次形
最小２乗法を用いて同定した流量係数から溶鋼流量とノ
ズルの流量係数を非接触で計測し同定して制御すること
を特徴とした溶鋼流量の計測制御方法。In molten steel flow rate measurement control using a stopper orifice in a tundish, etc., the area between the stopper tuyeres into which molten steel flows, the molten steel head in the tundish, and the weight change at each sampling time of the tundish and ladle are used to calculate the sequential least squares method. A method for measuring and controlling a molten steel flow rate, characterized in that the molten steel flow rate and the flow coefficient of a nozzle are measured, identified, and controlled in a non-contact manner from the flow coefficient identified using the molten steel flow rate coefficient.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5095090A JPH03254345A (en) | 1990-03-02 | 1990-03-02 | Method for controlling measurement of molten steel flow rate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5095090A JPH03254345A (en) | 1990-03-02 | 1990-03-02 | Method for controlling measurement of molten steel flow rate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03254345A true JPH03254345A (en) | 1991-11-13 |
Family
ID=12873104
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5095090A Pending JPH03254345A (en) | 1990-03-02 | 1990-03-02 | Method for controlling measurement of molten steel flow rate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03254345A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100770337B1 (en) * | 2006-07-13 | 2007-10-25 | 주식회사 포스코 | Method for sensing weight of molten steel of flowing into tundish in twin roll strip casting process |
-
1990
- 1990-03-02 JP JP5095090A patent/JPH03254345A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100770337B1 (en) * | 2006-07-13 | 2007-10-25 | 주식회사 포스코 | Method for sensing weight of molten steel of flowing into tundish in twin roll strip casting process |
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