JP2014124637A - Control method of molten metal surface level in mold - Google Patents
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Abstract
Description
本発明は、溶鋼の連続鋳造設備におけるモールド内湯面レベル制御方法に関するものである。 The present invention relates to a mold level control method in a mold for continuous casting of molten steel.
溶鋼の連続鋳造は、タンディッシュから溶鋼をストッパーを備えたノズルを通じてモールド内に注入し、凝固させた鋳片をモールドの下方へ所定の鋳造速度Ｖｃで引き抜くことによって行われる。このような連続鋳造においては、モールド内の湯面レベルを一定の目標レベルに維持することが、操業の安定を図るとともに、鋳造品質を向上させるために重要である。 Continuous casting of molten steel is performed by injecting molten steel from a tundish into a mold through a nozzle provided with a stopper, and drawing the solidified slab at a predetermined casting speed Vc below the mold. In such continuous casting, it is important to maintain the molten metal surface level in the mold at a certain target level in order to stabilize the operation and improve the casting quality.
そこで従来から特許文献１に示すように、レベルセンサーによりモールド内湯面レベルを計測し、目標レベルとの偏差がゼロになるようにノズルのストッパー開度をフィードバック制御するモールド内湯面レベル制御が行なわれている。 Therefore, as shown in Patent Document 1, conventionally, a mold level level control is performed in which the level level in the mold is measured by a level sensor, and the stopper opening of the nozzle is feedback controlled so that the deviation from the target level becomes zero. ing.
しかしこのような従来のフィードバック制御法では、湯面レベルの変動が生じて偏差がある程度まで大きくなった後にノズルのストッパー開度を制御するため、湯面レベルを安定させることは容易ではなかった。特に溶鋼の連続鋳造設備においては、ときどきノズル詰まりが発生することがあるが、それによる湯面のレベル低下を検出してノズルのストッパー開度を大きくしても、ノズル詰まりによってノズルの流量特性が変化しているため、湯面レベルを目標レベルにまで復帰させるためにかなりの時間を要するという問題があった。 However, in such a conventional feedback control method, since the nozzle opening degree of the nozzle is controlled after fluctuation of the molten metal level occurs and the deviation becomes large to some extent, it is not easy to stabilize the molten metal level. Especially in continuous casting equipment for molten steel, nozzle clogging sometimes occurs, but even if the level drop of the molten metal level is detected and the nozzle stopper opening is increased, nozzle clogging causes the nozzle flow characteristics to be reduced. Due to the change, there is a problem that it takes a considerable time to return the hot water level to the target level.
従って本発明の目的は上記した従来の問題点を解決し、ノズル詰まりが発生した場合にも湯面レベルの変動を従来よりも小さくし、湯面レベルを安定させることができるモールド内湯面レベル制御方法を提供することである。 Therefore, the object of the present invention is to solve the above-mentioned conventional problems, and even when nozzle clogging occurs, the fluctuation of the molten metal surface level is made smaller than that of the conventional one, and the molten metal surface level control can stabilize the molten metal surface level. Is to provide a method.
上記の課題を解決するためになされた本発明は、モールドへの溶鋼注入量をノズルのストッパー開度により制御する連続鋳造設備におけるモールド内湯面レベル制御方法であって、溶鋼注入速度をストッパー開度Ｘの関数として求め、その溶鋼注入速度と引き抜き速度との差からモールド内湯面レベルの理論値を算出し算出されたモールド内湯面レベルの理論値をレベルセンサーで検出された湯面レベル実測値と比較して偏差を算出し、この偏差からノズルの流量特性を求め、その流量特性を用いて演算されたモールド内湯面レベルの理論値が目標レベルとなるように、ストッパー開度を制御する動作を一定周期で繰り返すことを特徴とするものである。 The present invention made in order to solve the above problems is a method for controlling a molten metal level in a continuous casting facility in which a molten steel injection amount into a mold is controlled by a stopper opening of a nozzle, and the molten steel injection speed is controlled by a stopper opening. Calculated as a function of X, the theoretical value of the mold level in the mold is calculated from the difference between the molten steel pouring rate and the drawing rate, and the calculated value of the mold level in the mold is calculated with the actual level value detected by the level sensor. The deviation is calculated by comparison, the flow rate characteristic of the nozzle is obtained from this deviation, and the stopper opening is controlled so that the theoretical value of the mold surface level calculated using the flow rate characteristic becomes the target level. It is characterized by repeating at a constant cycle.
なお請求項２のように、モールド内湯面レベルを、ストッパー開度Ｘの積分値から演算される湯面レベル上昇量と、引き抜き速度の積分値から演算される湯面レベル下降量とに基づいて算出することができる。また請求項３のように、上記一定周期を１〜５秒とすることができる。 As in claim 2, the hot water surface level in the mold is based on the hot water surface level increase amount calculated from the integrated value of the stopper opening X and the hot water surface level lowering amount calculated from the integrated value of the drawing speed. Can be calculated. Further, as in claim 3, the fixed period can be set to 1 to 5 seconds.
本発明のモールド内湯面レベル制御方法では、溶鋼注入速度をストッパー開度Ｘの関数として求め、その溶鋼注入速度と引き抜き速度との差からモールド内湯面レベルの理論値を算出する。このモールド内湯面レベルの理論値をレベルセンサーで検出された湯面レベル実測値と比較して理論値と実測値との偏差を求め、この偏差からノズルの流量特性を求める。そしてその流量特性を用いて演算されたモールド内湯面レベルの理論値が目標レベルとなるように、ストッパー開度を制御する。上記した一連の動作を、１〜５秒程度の一定周期で繰り返す。 In the mold level control method of the present invention, the molten steel injection speed is obtained as a function of the stopper opening X, and the theoretical value of the mold level in the mold is calculated from the difference between the molten steel injection speed and the drawing speed. The deviation between the theoretical value and the actual measurement value is obtained by comparing the theoretical value of the molten metal surface level in the mold with the actual measurement value of the molten metal level detected by the level sensor, and the flow rate characteristic of the nozzle is obtained from this deviation. Then, the stopper opening degree is controlled so that the theoretical value of the mold level in the mold calculated using the flow rate characteristic becomes the target level. The series of operations described above is repeated at a constant cycle of about 1 to 5 seconds.
このように、本発明ではモールド内湯面レベルの理論値が目標レベルとなるように制御を行ない、レベルセンサーで検出された湯面レベル実測値は理論値の補正に使用するだけである。このため１〜５秒程度、あるいはそれ以下の短い周期でストッパー開度を制御することができ、ノズル詰まりが生じた場合にもノズルの流量特性の低下を直ちにストッパー開度の制御に反映させることができる。この結果、偏差が検出された後にストッパー開度を制御する従来法に比較して、湯面レベルの変動を小さくし、湯面レベルを安定させることができる。 In this way, in the present invention, control is performed so that the theoretical value of the molten metal surface level in the mold becomes the target level, and the measured value of the molten metal surface level detected by the level sensor is only used for correcting the theoretical value. For this reason, the stopper opening can be controlled in a short cycle of about 1 to 5 seconds or less, and even when nozzle clogging occurs, the decrease in the flow characteristic of the nozzle is immediately reflected in the control of the stopper opening. Can do. As a result, as compared with the conventional method of controlling the stopper opening after the deviation is detected, the fluctuation of the molten metal level can be reduced and the molten metal level can be stabilized.
以下に本発明の実施形態を説明する。
図１は実施形態の連続鋳造設備の要部を示す断面図であり、１は溶鋼が供給されるタンディッシュ、２はタンディッシュ１の底面に設けられた溶鋼注入用のノズルである。本実施形態の連続鋳造設備は２つのノズル２を持つツインストリームタイプであるが、ノズル２は単一であっても３本以上であっても差支えない。各ノズル２の上部にはストッパー３が設けられており、ストッパー駆動機構４により個別に昇降させてストッパー開度を調節し、ノズル２の溶鋼注入量を制御することができる。ストッパー駆動機構４の駆動源は例えばステッピングモータであるが、これに限定されるものではない。
Embodiments of the present invention will be described below.
FIG. 1 is a cross-sectional view showing the main part of the continuous casting equipment of the embodiment, wherein 1 is a tundish to which molten steel is supplied, and 2 is a nozzle for pouring molten steel provided on the bottom surface of the tundish 1. Although the continuous casting equipment of this embodiment is a twin stream type having two nozzles 2, the nozzle 2 may be single or three or more. A stopper 3 is provided on the upper part of each nozzle 2, and the amount of molten steel injected into the nozzle 2 can be controlled by adjusting the stopper opening degree by individually moving up and down by the stopper driving mechanism 4. The drive source of the stopper drive mechanism 4 is, for example, a stepping motor, but is not limited to this.
各ノズル２の下部には連続鋳造用のモールド５が設けられている。本実施形態では同時に２ストリームの連続鋳造が行なわれる。モールド５の下部には多数のピンチロール６が配置されており、モールド５の下部から凝固させた鋳片を所定の鋳造速度Ｖｃで引き抜いている。 A mold 5 for continuous casting is provided below each nozzle 2. In this embodiment, two streams of continuous casting are performed simultaneously. A large number of pinch rolls 6 are arranged at the lower part of the mold 5, and the slab solidified from the lower part of the mold 5 is drawn at a predetermined casting speed Vc.
モールド５の内部にはレベルセンサーとして熱電対温度計７が所定間隔で埋設されており、モールド内の湯面レベルを検出している。このほかモールド５の上部には渦流式レベルセンサー８も設けられ、湯面レベルを測定している。本発明では、これらのレベルセンサーにより得られた湯面レベルの実測値は、モールド内湯面レベルの理論値を補正するために使用される。 Thermocouple thermometers 7 are embedded at predetermined intervals as a level sensor in the mold 5 to detect the level of hot water in the mold. In addition, an eddy current level sensor 8 is also provided on the upper part of the mold 5 to measure the surface level of the molten metal. In the present invention, the actual measured value of the molten metal level obtained by these level sensors is used to correct the theoretical value of the molten metal surface level in the mold.
本発明では、先ずモールド５への溶鋼の注入体積速度Ｑｉｎを数１の式により計算する。この数１において、Ｈはタンディッシュヘッド位置（ｍｍ）、αはノズル流量特性（ｋｇ/（ｓ・ｍｍ））、ρは溶鋼密度（ｋｇ/ｍｍ３）、Ｘはストッパー開度（ｍｍ）である。このＱｉｎをモールドの内部面積（ｍｍ２）で割ると湯面上昇速度（ｍｍ/ｓ）となる。 In the present invention, first, an injection volume velocity Qin of molten steel into the mold 5 is calculated by the equation (1). In Equation 1, H is the position of the tundish head (mm), α is the nozzle flow rate characteristic (kg / (s · mm)), ρ is the molten steel density (kg / mm 3 ), and X is the stopper opening (mm). is there. When this Qin is divided by the internal area (mm 2 ) of the mold, the molten metal surface rising speed (mm / s) is obtained.
引き抜き速度（ｍｍ/ｓ）をＶｃとし、目標湯面レベルを−１００（ｍｍ）とすると、モールド内湯面レベルの理論値は数２の式により表される。数２の式の右辺の第２項は湯面上昇量であり、ストッパー開度Ｘの積分値である。また右辺の第３項は湯面降下量であり、引き抜き速度Ｖｃの積分値である。このように本発明では、溶鋼注入速度と引き抜き速度との差からモールド内湯面レベルの理論値Ｌ（ｔ）を算出し、この数２の式により表されたモールド内湯面レベルの理論値Ｌ（ｔ）が常に目標湯面レベルとなるようにストッパー開度Ｘを調節する。 Assuming that the drawing speed (mm / s) is Vc and the target hot water surface level is −100 (mm), the theoretical value of the hot water surface level in the mold is expressed by the equation (2). The second term on the right side of Equation 2 is the amount of rise in the molten metal surface, and is an integral value of the stopper opening X. The third term on the right side is the amount of molten metal fall, and is an integrated value of the drawing speed Vc. As described above, in the present invention, the theoretical value L (t) of the molten metal surface level is calculated from the difference between the molten steel pouring rate and the drawing speed, and the theoretical value L ( The stopper opening X is adjusted so that t) always becomes the target hot water level.
前記したように、連続鋳造設備においては地金付着によるノズル詰まりが発生することがあり、その場合にはストッパー開度Ｘから計算された溶鋼の注入体積速度Ｑｉｎよりも実際の溶鋼の注入体積速度は低下することとなる。そこで本発明では、レベルセンサーによってモールド内湯面レベルを検出し、検出された湯面レベル実測値とモールド内湯面レベルの理論値Ｌ（ｔ）とを比較して理論値と実測値との偏差を求める。 As described above, in a continuous casting facility, nozzle clogging due to adhesion of metal may occur. In this case, the actual molten steel injection volume velocity Qin is calculated from the molten steel injection volume velocity Qin calculated from the stopper opening X. Will drop. Therefore, in the present invention, the level level sensor detects the level of the molten metal in the mold, and compares the detected measured level of the molten metal level with the theoretical value L (t) of the level of the molten metal level in the mold to determine the deviation between the theoretical value and the measured value. Ask.
例えば図２のグラフに示すように、レベルセンサーによる湯面レベル実測値が湯面レベルの理論値Ｌ（ｔ）よりも低下し、その偏差がＫであったとすると、その間（ｎからｎ+１までの間）のノズルの流量特性はα（ｎ）は、それ以前の流量特性はα（ｎ−１）よりも低下しており、数３の式により表される。具体的には、Ｌ（ｔ）＝−１００（ｍｍ）、Ｋ＝２０（ｍｍ）であるとすると、α（ｎ）＝−１００／（−１００−２０）＝０.８３α（ｎ−１）となる。 For example, as shown in the graph of FIG. 2, if the measured value of the molten metal surface level by the level sensor is lower than the theoretical value L (t) of the molten metal surface level, and its deviation is K, then (n to n + 1) The flow rate characteristics of the nozzles until () are α (n), and the previous flow rate characteristics are lower than α (n−1), and are expressed by the equation (3). Specifically, if L (t) = − 100 (mm) and K = 20 (mm), α (n) = − 100 / (− 100−20) = 0.83α (n−1) It becomes.
このようにノズル詰まりにより流量特性α（ｎ）が正常時の８３％にまで低下したことが検出された場合には、ストッパー開度Ｘを大きくして注入速度を増加させる必要がある。そこでこの低下率（０.８３）の逆数βを算出して数４の式に代入し、モールド内湯面レベルの理論値Ｌ（ｔ）が目標レベルである−１００（ｍｍ）となるように、ストッパー開度Ｘを補正制御する。 Thus, when it is detected that the flow rate characteristic α (n) has decreased to 83% of the normal value due to nozzle clogging, it is necessary to increase the stopper opening X and increase the injection speed. Therefore, the reciprocal β of this reduction rate (0.83) is calculated and substituted into the equation (4), so that the theoretical value L (t) of the mold surface level in the mold becomes −100 (mm) which is the target level. The stopper opening X is corrected and controlled.
本発明では、上記した一連の動作を１〜５秒程度の一定周期で繰り返すので、ノズル詰まりが生じた場合にもノズルの流量特性の低下を直ちにストッパー開度の制御に反映させることができ、従来法に比較して湯面レベルの変動を小さくし、湯面レベルを安定させることができる。なお本発明は定常運転状態において湯面レベルを一定に保つことを目的としたモールド内湯面レベル制御方法であり、湯面レベルを上昇させて行く鋳造開始時（オートスタート時）には、別の制御方法が用いられる。 In the present invention, since the series of operations described above is repeated at a constant cycle of about 1 to 5 seconds, even when nozzle clogging occurs, a decrease in the flow rate characteristic of the nozzle can be immediately reflected in the control of the stopper opening degree, Compared with the conventional method, the fluctuation of the hot water level can be reduced and the hot water level can be stabilized. The present invention is a mold level control method in the mold for the purpose of keeping the molten metal level constant in a steady operation state. When casting starts to increase the molten metal level (automatic start), A control method is used.
１ タンディッシュ
２ ノズル
３ ストッパー
４ ストッパー駆動機構
５ モールド
６ ピンチロール
７ 熱電対温度計
８ 渦流式レベルセンサー
1 Tundish 2 Nozzle 3 Stopper 4 Stopper drive mechanism 5 Mold 6 Pinch roll 7 Thermocouple thermometer 8 Eddy current level sensor
Claims (3)
溶鋼注入速度をストッパー開度Ｘの関数として求め、その溶鋼注入速度と引き抜き速度との差からモールド内湯面レベルの理論値を算出し、
算出されたモールド内湯面レベルの理論値をレベルセンサーで検出された湯面レベル実測値と比較して偏差を算出し、
この偏差からノズルの流量特性を求め、その流量特性を用いて演算されたモールド内湯面レベルの理論値が目標レベルとなるように、ストッパー開度を制御する動作を一定周期で繰り返すことを特徴とするモールド内湯面レベル制御方法。 A molten metal level control method in a continuous casting facility for controlling the amount of molten steel injected into the mold by the stopper opening of the nozzle,
The molten steel injection speed is obtained as a function of the stopper opening X, and the theoretical value of the molten metal surface level in the mold is calculated from the difference between the molten steel injection speed and the drawing speed.
Compare the calculated theoretical value of the molten metal surface level in the mold with the actual molten metal surface level detected by the level sensor, and calculate the deviation.
The flow rate characteristic of the nozzle is obtained from this deviation, and the operation of controlling the stopper opening is repeated at a constant cycle so that the theoretical value of the mold surface level calculated using the flow rate characteristic becomes the target level. A mold level control method in the mold.
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| KR102336755B1 (en) * | 2020-08-25 | 2021-12-07 | 현대제철 주식회사 | Apparatus and method for controlling stopper speed of continuous casting machine |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS49133222A (en) * | 1972-10-17 | 1974-12-20 | ||
| JPS5927762A (en) * | 1982-08-09 | 1984-02-14 | Nippon Steel Corp | Method for controlling level of molten steel in casting mold for continuous casting |
| JPH0857617A (en) * | 1994-08-19 | 1996-03-05 | Nippon Steel Corp | Automatic start controller for continuous casting |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS49133222A (en) * | 1972-10-17 | 1974-12-20 | ||
| JPS5927762A (en) * | 1982-08-09 | 1984-02-14 | Nippon Steel Corp | Method for controlling level of molten steel in casting mold for continuous casting |
| JPH0857617A (en) * | 1994-08-19 | 1996-03-05 | Nippon Steel Corp | Automatic start controller for continuous casting |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| KR102336755B1 (en) * | 2020-08-25 | 2021-12-07 | 현대제철 주식회사 | Apparatus and method for controlling stopper speed of continuous casting machine |
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