JPH04284955A - Method and device for plasma-heating molten steel in tundish - Google Patents
Method and device for plasma-heating molten steel in tundishInfo
- Publication number
- JPH04284955A JPH04284955A JP3048310A JP4831091A JPH04284955A JP H04284955 A JPH04284955 A JP H04284955A JP 3048310 A JP3048310 A JP 3048310A JP 4831091 A JP4831091 A JP 4831091A JP H04284955 A JPH04284955 A JP H04284955A
- Authority
- JP
- Japan
- Prior art keywords
- torch
- plasma
- molten steel
- voltage
- detector
- 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
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 62
- 239000010959 steel Substances 0.000 title claims abstract description 62
- 238000010438 heat treatment Methods 0.000 title claims abstract description 32
- 238000000034 method Methods 0.000 title claims abstract description 15
- 230000002159 abnormal effect Effects 0.000 claims abstract description 10
- 230000001174 ascending effect Effects 0.000 claims abstract description 9
- 230000002265 prevention Effects 0.000 claims description 24
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 21
- 238000003780 insertion Methods 0.000 claims description 10
- 230000037431 insertion Effects 0.000 claims description 10
- 230000003028 elevating effect Effects 0.000 claims description 6
- 239000002184 metal Substances 0.000 description 8
- 238000010586 diagram Methods 0.000 description 7
- 230000033228 biological regulation Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
Landscapes
- Plasma Technology (AREA)
- Continuous Casting (AREA)
- Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、吊り下げ昇降式のプラ
ズマト−チを用いるタンディッシュ内溶鋼のプラズマ加
熱方法及びその装置に係り、特に、溶鋼とプラズマト−
チの異常接近防止方法及び異常接近防止機構を備えたプ
ラズマ加熱装置に関する。[Field of Industrial Application] The present invention relates to a method and apparatus for plasma heating molten steel in a tundish using a suspended lifting type plasma torch, and more particularly, to
The present invention relates to a plasma heating device equipped with an abnormal approach prevention method and an abnormal approach prevention mechanism.
【０００２】0002
【従来の技術】鋼の連続鋳造においては、溶鋼を加熱し
その温度を適正に維持する操作が行われている。溶鋼加
熱手段の一つとしてプラズマア−クによる加熱があり、
このプラズマ加熱技術としては、実開昭６１−５３０５
２号公報に示されたものがある。2. Description of the Related Art In continuous casting of steel, operations are performed to heat molten steel and maintain its temperature appropriately. One of the methods of heating molten steel is heating by plasma arc.
This plasma heating technology is based on Utility Model Application No. 61-5305.
There is one shown in Publication No. 2.
【０００３】図４において、１はタンディッシュ、２は
取鍋に接続されるロングノズル、３は溶鋼をモ−ルドに
注入するための浸漬ノズルであり、４は溶鋼を示す。タ
ンディッシュ１はカバ−５で覆われており、その一部が
堰７で区画され、且つ加熱室カバ−８で覆われた加熱室
６になっている。又、加熱室６には、加熱室カバ−８を
貫通させて陰極であるプラズマト−チ９が挿入され、タ
ンディッシュ内の溶鋼４に接する位置に陽極１０が配置
されている。１２は電源である。そして、プラズマト−
チ９と陽極１０とに接している溶鋼４との間にプラズマ
ア−ク１１を発生させ、溶鋼４を適度に加熱するように
なっている。この溶鋼の加熱温度は投入電力によって決
定されるので、溶鋼４の加熱中には、投入電力を調節す
る操作が行われる。In FIG. 4, 1 is a tundish, 2 is a long nozzle connected to a ladle, 3 is a submerged nozzle for injecting molten steel into a mold, and 4 indicates molten steel. The tundish 1 is covered with a cover 5, a part of which is partitioned by a weir 7, and forms a heating chamber 6 covered with a heating chamber cover 8. A plasma torch 9 serving as a cathode is inserted into the heating chamber 6 through a heating chamber cover 8, and an anode 10 is disposed at a position in contact with the molten steel 4 in the tundish. 12 is a power source. And plasma
A plasma arc 11 is generated between the molten steel 4 in contact with the chi 9 and the anode 10, and the molten steel 4 is heated appropriately. Since the heating temperature of this molten steel is determined by the input power, an operation for adjusting the input power is performed while the molten steel 4 is being heated.
【０００４】0004
【発明が解決しようとする課題】上述した投入電力の調
節は、プラズマト−チ９と溶鋼の湯面１３との間隔（以
下、ト−チ・湯面間距離と言う）、即ちプラズマア−ク
長を適切な距離に保って、プラズマ状態をできるだけ安
定させた状態にし、電流値の変更操作を行うことによっ
てなされる。この際、加熱室６は加熱室カバ−８で覆わ
れており、ト−チ・湯面間距離の観察はできないので、
使用するタンディッシュの外形高さ寸法、湯面高さを予
め確認しておき、所望するア−ク長に相当するプラズマ
ト−チの下降位置を計算し、その計算結果に合わせてプ
ラズマト−チを下降又は上昇させている。[Problems to be Solved by the Invention] The above-mentioned adjustment of the input power is performed by adjusting the distance between the plasma torch 9 and the molten steel surface 13 (hereinafter referred to as the distance between the torch and the molten steel surface), that is, the distance between the plasma torch 9 and the molten steel surface 13. This is done by keeping the plasma at an appropriate distance, keeping the plasma state as stable as possible, and then changing the current value. At this time, the heating chamber 6 is covered with a heating chamber cover 8, and the distance between the torch and the hot water surface cannot be observed.
Check the external height of the tundish and the hot water level in advance, calculate the lowering position of the plasma torch that corresponds to the desired arc length, and adjust the plasma torch according to the calculation results. lowering or raising the tip.
【０００５】このため、ト−チ・湯面間距離を所定長さ
に維持することは困難である。本出願人は、このような
問題に対処し、先に、特願平２−８８６８４号（以下、
先願と言う）として、湯面１３の変動に追従してト−チ
・湯面間距離を一定にすることができるプラズマ加熱装
置を提案している。[0005] For this reason, it is difficult to maintain the distance between the torch and the molten metal surface to a predetermined length. The present applicant dealt with such problems and previously filed Japanese Patent Application No. 2-88684 (hereinafter referred to as
As a prior application), we have proposed a plasma heating device that can follow fluctuations in the hot water level 13 and keep the distance between the torch and the hot water level constant.
【０００６】図３は先願の一実施例を示す図である。図
３において、１はタンディッシュ−６は加熱室、８は加
熱室カバ−、９はプラズマト−チ、１４はト−チ昇降機
構であり、４は溶鋼を示す。この装置には、タンディッ
シュ１と受け入れた溶鋼４の全重量を測定するロ−ドセ
ル１５と、プラズマト−チの挿入位置検出器１６、及び
制御機構１７が備えられている。なお、この図において
は、溶鋼の湯面１３の高さをＨ、プラズマト−チ９の挿
入長さをＹ、ト−チ・湯面間距離をＬとして表示してい
る。FIG. 3 is a diagram showing an embodiment of the prior application. In FIG. 3, 1 is a tundish, 6 is a heating chamber, 8 is a heating chamber cover, 9 is a plasma torch, 14 is a torch lifting mechanism, and 4 is molten steel. This device is equipped with a load cell 15 for measuring the total weight of the tundish 1 and the received molten steel 4, a plasma torch insertion position detector 16, and a control mechanism 17. In this figure, H is the height of the molten steel surface 13, Y is the insertion length of the plasma torch 9, and L is the distance between the torch and the molten metal surface.
【０００７】この装置においては、ロ−ドセル１５によ
ってタンディッシュ１内の溶鋼４の重量を求め（タンデ
ィッシュ１自体の重量は事前に測定しておき）、予め確
認されている溶鋼重量と湯面高さの関係によって、溶鋼
４の湯面高さを求める。又、ト−チ挿入位置検出器１６
によって得たト−チ挿入長さを得る。そして、上述の湯
面高さとト−チ挿入長さとを制御機構１７に入力し、演
算によってト−チ・湯面間距離を連続的に求める。次い
で、演算によって求めたト−チ・湯面間距離が、別途外
部から設定されるト−チ・湯面間距離に一致するように
、制御機構１７がト−チ昇降機構１４を作動させてプラ
ズマト−チ９を昇降させる。In this device, the weight of the molten steel 4 in the tundish 1 is determined by the load cell 15 (the weight of the tundish 1 itself is measured in advance), and the molten steel weight and the molten metal level, which have been confirmed in advance, are determined. The height of the molten steel 4 is determined based on the height relationship. In addition, the torch insertion position detector 16
Obtain the torch insertion length obtained by Then, the above-described hot water level height and torch insertion length are input to the control mechanism 17, and the distance between the torch and the hot water level is continuously determined by calculation. Next, the control mechanism 17 operates the torch lifting mechanism 14 so that the distance between the torch and the hot water surface obtained by the calculation matches the distance between the torch and the hot water surface that is separately set from the outside. The plasma torch 9 is raised and lowered.
【０００８】上記のように、先願の装置は、タンディッ
シュ１内の溶鋼の湯面１３が変動しても、ト−チ・湯面
間距離を一定の設定距離に制御する構成になっている。As mentioned above, the device of the prior application is configured to control the distance between the torch and the molten metal level to a constant set distance even if the molten steel level 13 in the tundish 1 fluctuates. There is.
【０００９】しかし、上記先願の装置においても、なお
改良すべき問題が残されている。即ち、ロ−ドセル１５
によって得た重量を基に求めた溶鋼の湯面高さの精度は
、必ずしも充分ではない。However, even with the device of the prior application, there are still problems that need to be improved. That is, the load cell 15
The accuracy of the height of the molten steel surface determined based on the weight obtained by the method is not necessarily sufficient.
【００１０】■ タンディッシュの内側には、その一
部に地金が付着していたり、或いは内張り耐火物に欠損
箇所が生じていたりする。又、各タンディッシュの内寸
法の施工誤差も大きい。このため、重量−溶鋼湯面高さ
の関係は、各タンディッシュ毎に異なり、正確には一定
ではない。[0010] On the inside of the tundish, metal may be attached to a part thereof, or there may be defects in the refractory lining. Furthermore, there is a large construction error in the internal dimensions of each tundish. Therefore, the relationship between weight and molten steel level height differs for each tundish and is not exactly constant.
【００１１】■ 溶鋼上には、溶鋼よりも軽いスラグ
が浮上しており、実際の湯面高さは低い値を示す。■ Slag, which is lighter than the molten steel, floats on top of the molten steel, and the actual molten metal level shows a low value.
【００１２】このため、上述の溶鋼湯面高さの誤差と、
制御機構１７とト−チ昇降機構１４によるプラズマト−
チ９の位置制御精度との関係によっては、プラズマト−
チ９の先端が溶鋼４に接触する虞もある。プラズマト−
チ９と溶鋼４との接触が起これば、プラズマト−チ９が
損傷してしまうと共に、水冷構造のプラズマト−チ９か
ら水が流出し、水蒸気爆発を起こす虞さえある。[0012] Therefore, the above-mentioned error in the molten steel level height,
Plasma torch by control mechanism 17 and torch lifting mechanism 14
Depending on the relationship with the position control accuracy of the
There is also a possibility that the tip of the chi 9 may come into contact with the molten steel 4. Plasmato
If contact between the torch 9 and the molten steel 4 occurs, the plasma torch 9 will be damaged, and water may flow out of the water-cooled plasma torch 9, causing a steam explosion.
【００１３】本発明は、従来技術の問題点を解決すると
共に、先願の装置をも改良し、タンディッシュ内溶鋼と
プラズマト−チとの異常接近を防止できるプラズマ加熱
方法及び異常接近防止機構を備えたプラズマ加熱装置を
提供することを目的とする。The present invention solves the problems of the prior art, improves the device of the prior application, and provides a plasma heating method and an abnormal approach prevention mechanism that can prevent the molten steel in the tundish from coming close to the plasma torch. An object of the present invention is to provide a plasma heating device equipped with the following.
【００１４】[0014]
【課題を解決するための手段】本発明は、吊り下げ昇降
式のプラズマト−チを用いた場合における溶鋼とプラズ
マト−チとの異常接近防止ができるプラズマ加熱方法と
、溶鋼とプラズマト−チとの異常接近防止機構を備えた
プラズマ加熱装置に係るものである。[Means for Solving the Problems] The present invention provides a plasma heating method that can prevent abnormal approach between molten steel and the plasma torch when a suspended lifting type plasma torch is used, and This relates to a plasma heating device equipped with a mechanism for preventing abnormal access between the plasma and the plasma.
【００１５】上記の目的を達成するために、第一の発明
の方法においては、プラズマト−チと溶鋼との間に生ず
るプラズマ電圧を測定し、このプラズマ電圧値が下限設
定値以下になれば、下限設定値を超えるまでプラズマト
−チを上昇させ、このプラズマト−チと溶鋼との異常接
近を防止する。[0015] In order to achieve the above object, in the method of the first invention, the plasma voltage generated between the plasma torch and the molten steel is measured, and if the plasma voltage value becomes below the lower limit set value, , the plasma torch is raised until it exceeds the lower limit set value to prevent abnormal approach between the plasma torch and the molten steel.
【００１６】第二の発明のプラズマト−チにおいては、
プラズマト−チを昇降させるト−チ昇降機構と、プラズ
マト−チと溶鋼との間に生ずるプラズマ電圧を測定する
電圧検出器と、この電圧検出器によって測定されたプラ
ズマ電圧値と予め設定された下限プラズマ電圧設定値と
を比較し、測定プラズマ電圧値が設定電圧値より小さい
場合にはト−チ接近信号を発生するト−チ接近検出器と
、このト−チ接近信号を前記ト−チ昇降機構に送られる
他のト−チ昇降指令信号よりも優先させてト−チ昇降機
構に上昇指令信号を伝送するト−チ接近防止優先回路よ
りなるト−チ接近防止機構とを備えている。In the plasma torch of the second invention,
A torch lifting mechanism that lifts and lowers the plasma torch, a voltage detector that measures the plasma voltage generated between the plasma torch and the molten steel, and a plasma voltage value measured by the voltage detector that is set in advance. a torch approach detector that compares the measured plasma voltage value with the lower limit plasma voltage setting value and generates a torch approach signal if the measured plasma voltage value is smaller than the set voltage value; A torch approach prevention mechanism comprising a torch approach prevention priority circuit that transmits a rise command signal to the torch rise and fall mechanism with priority over other torch rise and fall command signals sent to the torch rise and fall mechanism. There is.
【００１７】第三の発明のプラズマト−チにおいては、
タンディッシュ内の溶鋼の湯面高さを検出する重量式湯
面検出器と、タンディッシュ内へのプラズマト−チの挿
入長さを検出するト−チ位置検出器と、重量式湯面検出
器によって検出された湯面高さ及びト−チ位置検出器に
よって検出されたプラズマト−チの挿入長さに基づいて
ト−チ・湯面間距離の制御を行うための信号を発するト
−チ昇降指令器よりなるト−チ昇降機構を備えると共に
、プラズマト−チと溶鋼との間に生ずるプラズマ電圧を
測定する電圧検出器と、この電圧検出器によって測定さ
れたプラズマ電圧値と予め設定された下限プラズマ電圧
設定値とを比較し、測定されたプラズマ電圧値が下限プ
ラズマ電圧設定値より小さい場合にはプラズマト−チを
上昇させる指令信号を発するト−チ接近検出器と、上昇
指令信号を受信しこの上昇指令信号をト−チ昇降機構に
与えられる他の昇降指令信号より優先させてト−チ昇降
機構に伝送するト−チ接近防止優先回路よりなるト−チ
接近防止機構を備えている。In the plasma torch of the third invention,
A gravimetric level detector that detects the height of the molten steel in the tundish, a torch position detector that detects the insertion length of the plasma torch into the tundish, and a gravimetric level detector that detects the length of the plasma torch inserted into the tundish. A torch that emits a signal to control the distance between the torch and the hot water surface based on the hot water level height detected by the torch position detector and the insertion length of the plasma torch detected by the torch position detector. It is equipped with a torch raising and lowering mechanism consisting of a torch raising and lowering command device, a voltage detector that measures the plasma voltage generated between the plasma torch and the molten steel, and a plasma voltage value measured by this voltage detector and a preset value. A torch proximity detector that compares the measured plasma voltage value with the lower limit plasma voltage setting value and issues a command signal to raise the plasma torch if the measured plasma voltage value is smaller than the lower limit plasma voltage set value; A torch approach prevention mechanism comprising a torch approach prevention priority circuit that receives the signal and transmits the ascending command signal to the torch ascending/descending mechanism with priority over other ascending/descending command signals given to the torch ascending/descending mechanism. We are prepared.
【００１８】[0018]
【作用】電極であるプラズマト−チと溶鋼湯面の間に生
ずるプラズマ電圧は、次式のように、電極電圧降下とプ
ラズマ柱電圧降下よりなる。[Operation] The plasma voltage generated between the plasma torch, which is an electrode, and the molten steel surface is composed of an electrode voltage drop and a plasma column voltage drop, as shown in the following equation.
【００１９】Ｖｐ ＝Ｖｎ ＋Ｖｃ
Ｖｐ ；プラズマ電圧
Ｖｎ ；電極電圧降下
Ｖｃ ；プラズマ柱電圧降下
ここで、電極電圧降下Ｖｎ は陰極電圧降下と陽極電圧
降下の和を示す。この電極電圧降下Ｖｎ は、プラズマ
電流ともト−チ・湯面間距離とも関係がない。一方、プ
ラズマ柱電圧降下Ｖｃ はプラズマ長の拡大と共に一様
に上昇する特性を持つ。従って、プラズマ電圧Ｖｐ の
値は、ト−チ・湯面間距離の大小によって、増大又は減
少する。Vp = Vn + Vc Vp ; Plasma voltage Vn ; Electrode voltage drop Vc ; Plasma column voltage drop Here, the electrode voltage drop Vn represents the sum of the cathode voltage drop and the anode voltage drop. This electrode voltage drop Vn has no relation to the plasma current or the distance between the torch and the hot metal surface. On the other hand, the plasma column voltage drop Vc has a characteristic of increasing uniformly as the plasma length increases. Therefore, the value of the plasma voltage Vp increases or decreases depending on the distance between the torch and the molten metal surface.
【００２０】このよに、プラズマ電圧Ｖｐ の値を所定
の値（下限値）以下にならないようにすれば、プラズマ
ト−チの先端と湯面とが接触することはない。[0020] In this way, if the value of the plasma voltage Vp is kept below a predetermined value (lower limit value), the tip of the plasma torch will not come into contact with the hot water surface.
【００２１】[0021]
【実施例】図１は本発明の方法及びその装置係る一実施
例の構成を示す図である。図１において、タンディッシ
ュについては、その構造が図４の場合と同様にしたので
、タンディッシュに関する同一の構成部分については同
じ符号を付し説明を省略する。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing the structure of an embodiment of the method and apparatus of the present invention. In FIG. 1, the structure of the tundish is the same as that in FIG. 4, so the same reference numerals are given to the same components regarding the tundish, and the explanation thereof will be omitted.
【００２２】本実施例におけるプラズマト−チは吊り下
げ昇降式の機構を備えたものであって、ト−チ昇降機構
１８は、ワイヤによって懸吊されたプラズマト−チ９を
昇降させるト−チ巻上機１９、巻上機１９を駆動させる
ト−チ昇降駆動機２０、及びタンディッシュ１内におけ
るプラズマト−チ９の挿入長さＬｎ を検出するト−チ
位置検出器２１よりなる。２２は支持フレ−ムである。The plasma torch in this embodiment is equipped with a suspended lifting mechanism, and the torch lifting mechanism 18 is a torch that lifts and lowers the plasma torch 9 suspended by a wire. It consists of a torch hoist 19, a torch lifting drive 20 for driving the hoist 19, and a torch position detector 21 for detecting the insertion length Ln of the plasma torch 9 in the tundish 1. 22 is a support frame.
【００２３】又、１２はプラズマ電源、３１はプラズマ
電圧検出器である。そして、２３は湯面検出器で、重量
検出器２４と湯面変換器２５よりなる。更に、２６はア
−ク長の演算器、２７はト−チ昇降指令器、２８はア−
ク長設定器、３２はト−チ接近検出器、３６はト−チ接
近防止優先回路である。Further, 12 is a plasma power source, and 31 is a plasma voltage detector. 23 is a hot water level detector, which is composed of a weight detector 24 and a hot water level converter 25. Furthermore, 26 is an arc length calculator, 27 is a torch lift/lower command unit, and 28 is an arc length calculator.
32 is a torch approach detector, and 36 is a torch approach prevention priority circuit.
【００２４】まず、ト−チ昇降機構１８は、ト−チ接近
防止優先回路３６からト−チ昇降駆動機２０に与えられ
るト−チ上昇指令信号４３又はト−チ下降指令信号４０
に従い、上昇下降又は停止を行っている。ト−チ上昇指
令信号４３及びト−チ下降指令信号４０はト−チ昇降指
令器２７が発するア−ク長拡大指令信号２９、ア−ク長
縮小指令信号３０にそれぞれ対応している。通常、ト−
チ昇降指令器２７は、現状ア−ク長の演算器２６の出力
Ｌｇ がア−ク長設定器２８の出力Ｌｒ に一致するよ
うに、ト−チ昇降指令を発するので、ト−チ・湯面間距
離Ｌｇ は設定で定める一定値に維持される。First, the torch raising/lowering mechanism 18 receives a torch raising command signal 43 or a torch lowering command signal 40 given to the torch raising/lowering drive unit 20 from the torch approach prevention priority circuit 36.
According to the regulations, the robot is raising, lowering, or stopping. The torch up command signal 43 and the torch down command signal 40 correspond to the arc length expansion command signal 29 and the arc length reduction command signal 30 issued by the torch up/down command device 27, respectively. Usually, to
The torch lift/lower command unit 27 issues a torch lift/lower command so that the output Lg of the current arc length calculator 26 matches the output Lr of the arc length setter 28, so that the torch/hot water The inter-plane distance Lg is maintained at a constant value determined by the settings.
【００２５】一方、プラズマ電圧検出器３１が測定した
プラズマ電圧信号は、ト−チ接近検出器３２に送られる
。そして、この測定電圧が下限の基準値まで下がった場
合には、この電圧が基準値を超えて復帰するまでト−チ
接近信号３３をト−チ接近防止優先回路３６に与える。
ト−チ接近防止優先回路３６はト−チ接近信号３３を受
信すると、ト−チ昇降指令器２７から受信する指令を無
効とし、ト−チ昇降機構１８にト−チ上昇指令信号４３
を与える。On the other hand, the plasma voltage signal measured by the plasma voltage detector 31 is sent to the torch approach detector 32. When this measured voltage drops to the lower limit reference value, the torch approach signal 33 is applied to the torch approach prevention priority circuit 36 until this voltage exceeds the reference value and returns. When the torch approach prevention priority circuit 36 receives the torch approach signal 33, it invalidates the command received from the torch lift command device 27 and sends the torch raise command signal 43 to the torch lift mechanism 18.
give.
【００２６】このような構成によれば、プラズマト−チ
９と溶鋼湯面１３とが異常接近したり、或いは接触する
ようなことなく、ト−チ・湯面間距離を適正な状態に維
持することができる。According to this configuration, the distance between the torch and the molten steel surface 13 can be maintained in an appropriate state without the plasma torch 9 and the molten steel surface 13 coming into abnormal proximity or contacting each other. can do.
【００２７】図２は図１におけるト−チ接近防止機構の
構成を示す図である。図２においては、ト−チ接近検出
器３２及びト−チ接近防止優先回路３６の詳細について
説明する。ト−チ接近検出器３２は、下限プラズマの電
圧を設定するためのプラズマ電圧設定器３４とこのプラ
ズマ電圧設定器３４より設定された下限プラズマの電圧
値Ｂと、電圧検出器３１によって測定されたプラズマ電
圧値Ａとを比較するプラズマ電圧比較器３５よりなる。FIG. 2 is a diagram showing the structure of the torch access prevention mechanism in FIG. 1. Referring to FIG. 2, details of the torch approach detector 32 and the torch approach prevention priority circuit 36 will be described. The torch approach detector 32 includes a plasma voltage setter 34 for setting the lower limit plasma voltage, a lower limit plasma voltage value B set by the plasma voltage setter 34, and a lower limit plasma voltage value B measured by the voltage detector 31. It consists of a plasma voltage comparator 35 that compares the plasma voltage value A with the plasma voltage value A.
【００２８】ト−チ接近検出器３２においては、設定さ
れた下限プラズマ電圧値Ｂと測定されたプラズマ電圧値
Ａとを比較し、測定プラズマ電圧値Ａが下限プラズマ電
圧値Ｂよりも小さい場合、ト−チ接近防止優先回路３６
にト−チ接近信号３３を送る。The torch approach detector 32 compares the set lower limit plasma voltage value B with the measured plasma voltage value A, and if the measured plasma voltage value A is smaller than the lower limit plasma voltage value B, Torch access prevention priority circuit 36
The torch approach signal 33 is sent to
【００２９】ト−チ接近防止優先回路３６においては、
ト−チ接近信号３３を受信すると、下降阻止接点３８が
開路し、ト−チ昇降指令器２７からのア−ク長縮小指令
信号３０を無効にする。この時同時に、接近退避接点４
１が閉路し、ア−ク長拡大指令信号２９の有無にかかわ
らず、ト−チ昇降制御リレ−４２を作動させる。ト−チ
昇降制御リレ−４２の作動により、ト−チ昇降駆動機２
０に上昇指令信号４３が伝送される。そして、ト−チ上
昇制御リレ−４２の動作は、測定プラズマ電圧Ａが下限
プラズマ電圧Ｂを超え、接近退避接点４１が復帰（開路
）するまで続く。In the torch approach prevention priority circuit 36,
When the torch approach signal 33 is received, the lowering prevention contact 38 opens and the arc length reduction command signal 30 from the torch raising/lowering command unit 27 is invalidated. At this time, at the same time, approach/evacuation contact 4
1 is closed, and the torch elevating control relay 42 is activated regardless of the presence or absence of the arc length expansion command signal 29. The torch lift drive machine 2 is activated by the operation of the torch lift control relay 42.
0, a rising command signal 43 is transmitted. The operation of the torch raising control relay 42 continues until the measured plasma voltage A exceeds the lower limit plasma voltage B and the approach/retreat contact 41 returns (opens).
【００３０】[0030]
【発明の効果】本発明は、プラズマト−チと溶鋼との間
に生ずるプラズマ電圧を測定し、このプラズマ電圧値が
下限設定値以下にならないようにプラズマト−チを上昇
させるプラズマ加熱方法、及びプラズマ電圧値が下限設
定値以下になった場合にプラズマト−チを上昇させるト
−チ接近防止機構を備えたプラズマ加熱装置である。Effects of the Invention The present invention provides a plasma heating method in which a plasma voltage generated between a plasma torch and molten steel is measured, and the plasma torch is raised so that the plasma voltage value does not fall below a lower limit set value. The plasma heating apparatus is also equipped with a torch approach prevention mechanism that raises the plasma torch when the plasma voltage value falls below a lower limit set value.
【００３１】本発明によれば、プラズマト−チと溶鋼湯
面とが異常接近したり、或いは接触するようなことなく
、ト−チ・湯面間距離を適正な状態に維持することがで
き、安定した溶鋼加熱が実施できる。According to the present invention, the distance between the torch and the molten steel surface can be maintained in an appropriate state without the plasma torch and the molten steel surface coming into abnormal proximity or contacting each other. , stable heating of molten steel can be carried out.
【図１】本発明の方法及びその装置に係る一実施例の構
成を示す図である。FIG. 1 is a diagram showing the configuration of an embodiment of the method and apparatus of the present invention.
【図２】図１におけるト−チ接近防止機構の構成を示す
図である。FIG. 2 is a diagram showing the configuration of the torch access prevention mechanism in FIG. 1;
【図３】先願の一実施例を示す図である。FIG. 3 is a diagram showing an example of the prior application.
【図４】従来のプラズマ加熱技術を示す図である。FIG. 4 is a diagram illustrating a conventional plasma heating technique.
１ タンディッシュ ４ 溶鋼 ６ 加熱室 ９ プラズマト−チ １０ 陽極 １１ プラズマア−ク １２ 電源 １３ 湯面 １８ ト−チ昇降機構 １９ 巻上機 ２０ ト−チ昇降駆動機 ２１ ト−チ位置検出器 ２３ 湯面検出器 ２４ 重量検出器 ２５ 湯面変換器 ２６ ア−ク長演算器 ２７ ト−チ昇降指令器 ２８ ア−ク長設定器 ２９ ア−ク長拡大指令信号 ３０ ア−ク長縮小指令信号 ３１ プラズマ電圧検出器 ３２ ト−チ接近検出器 ３３ ト−チ接近信号 ３４ プラズマ電圧設定器 ３５ プラズマ電圧比較器 ３６ ト−チ接近防止優先回路 ３８ 下降阻止接点 ３９ ト−チ下降制御用リレ− ４０ 下降指令信号 ４１ 接近退避接点 ４２ ト−チ上昇制御用リレ− ４３ 上昇指令信号 1 Tundish 4 Molten steel 6 Heating chamber 9 Plasma torch 10 Anode 11 Plasma arc 12 Power supply 13 Hot water surface 18 Torch lifting mechanism 19 Hoisting machine 20 Torch lifting/lowering drive machine 21 Torch position detector 23 Hot water level detector 24 Weight detector 25 Hot water level converter 26 Arc length calculator 27 Torch lift command device 28 Arc length setting device 29 Arc length expansion command signal 30 Arc length reduction command signal 31 Plasma voltage detector 32 Torch proximity detector 33 Torch approach signal 34 Plasma voltage setting device 35 Plasma voltage comparator 36 Torch access prevention priority circuit 38 Lowering prevention contact 39 Torch lowering control relay 40 Lowering command signal 41 Approach/evacuation contact 42 Torch lift control relay 43 Climb command signal
Claims (3)
いる溶鋼のプラズマ加熱方法において、前記プラズマト
−チと溶鋼との間に生ずるプラズマ電圧を測定し、この
プラズマ電圧値が下限設定値以下になれば、下限設定値
を超えるまで前記プラズマト−チを上昇させ、このプラ
ズマト−チと溶鋼との異常接近を防止することを特徴と
するタンディッシュ内溶鋼のプラズマ加熱方法。Claim 1: In a plasma heating method for molten steel using a suspended lifting type plasma torch, a plasma voltage generated between the plasma torch and the molten steel is measured, and the plasma voltage value is equal to or lower than a lower limit setting value. , the method for plasma heating molten steel in a tundish is characterized in that the plasma torch is raised until the lower limit setting value is exceeded to prevent abnormal approach between the plasma torch and the molten steel.
えた溶鋼加熱装置において、このプラズマト−チを昇降
させるト−チ昇降機構と、前記プラズマト−チと溶鋼と
の間に生ずるプラズマ電圧を測定する電圧検出器と、こ
の電圧検出器によって測定されたプラズマ電圧値と予め
設定された下限プラズマ電圧設定値とを比較し、測定プ
ラズマ電圧値が設定電圧値より小さい場合にはト−チ接
近信号を発生するト−チ接近検出器と、このト−チ接近
信号を前記ト−チ昇降機構に送られる他のト−チ昇降指
令信号よりも優先させてト−チ昇降機構に上昇指令信号
を伝送するト−チ接近防止優先回路よりなるト−チ接近
防止機構とを備えたことを特徴とするタンディッシュ内
溶鋼のプラズマ加熱装置。2. A molten steel heating apparatus equipped with a suspended, elevating type plasma torch, which includes a torch elevating mechanism for elevating and lowering the plasma torch, and a plasma generated between the plasma torch and the molten steel. A voltage detector that measures voltage compares the plasma voltage value measured by this voltage detector with a preset lower limit plasma voltage setting value, and if the measured plasma voltage value is smaller than the set voltage value, the a torch approach detector that generates a torch approach signal; and a torch approach detector that sends the torch approach signal to the torch lift mechanism with priority over other torch lift command signals sent to the torch lift mechanism. 1. A plasma heating device for molten steel in a tundish, characterized by comprising a torch approach prevention mechanism comprising a torch approach prevention priority circuit for transmitting a command signal.
えた溶鋼加熱装置において、タンディッシュ内の溶鋼の
湯面高さを検出する重量式湯面検出器と、前記タンディ
ッシュ内へのプラズマト−チの挿入長さを検出するト−
チ位置検出器と、前記重量式湯面検出器によって検出さ
れた湯面高さ及び前記ト−チ位置検出器によって検出さ
れたプラズマト−チの挿入長さに基づいてト−チ・湯面
間距離の制御を行うための信号を発するト−チ昇降指令
器よりなるト−チ昇降機構を備えると共に、前記プラズ
マト−チと溶鋼との間に生ずるプラズマ電圧を測定する
電圧検出器と、この電圧検出器によって測定されたプラ
ズマ電圧値と予め設定された下限プラズマ電圧設定値と
を比較し、前記測定されたプラズマ電圧値が前記下限プ
ラズマ電圧設定値より小さい場合には前記プラズマト−
チを上昇させる指令信号を発するト−チ接近検出器と、
前記上昇指令信号を受信しこの上昇指令信号を前記ト−
チ昇降機構に与えられる他の昇降指令信号より優先させ
て前記ト−チ昇降機構に伝送するト−チ接近防止優先回
路よりなるト−チ接近防止機構を備えたことを特徴とす
るタンディッシュ内溶鋼のプラズマ加熱装置。3. A molten steel heating apparatus equipped with a suspended lifting type plasma torch, comprising: a gravimetric molten steel level detector for detecting the level of the molten steel in the tundish; Torch to detect the insertion length of the torch
The torch and hot water level are determined based on the torch position detector, the hot water level height detected by the gravimetric hot water level detector, and the insertion length of the plasma torch detected by the torch position detector. a torch elevating mechanism comprising a torch elevating and lowering command device that emits a signal for controlling the distance between the plasma torch and the molten steel, and a voltage detector that measures the plasma voltage generated between the plasma torch and the molten steel; The plasma voltage value measured by this voltage detector is compared with a preset lower limit plasma voltage setting value, and if the measured plasma voltage value is smaller than the lower limit plasma voltage setting value, the plasma voltage value is lower than the lower limit plasma voltage setting value.
a torch proximity detector that issues a command signal to raise the torch;
The above-mentioned ascending command signal is received, and this ascending command signal is transmitted to the above-mentioned tow.
A tundish interior comprising a torch approach prevention mechanism comprising a torch approach prevention priority circuit that transmits to the torch lifting mechanism with priority over other lifting command signals given to the torch lifting mechanism. Plasma heating device for molten steel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3048310A JPH07110400B2 (en) | 1991-03-13 | 1991-03-13 | Plasma heating method and apparatus for molten steel in tundish |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3048310A JPH07110400B2 (en) | 1991-03-13 | 1991-03-13 | Plasma heating method and apparatus for molten steel in tundish |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04284955A true JPH04284955A (en) | 1992-10-09 |
| JPH07110400B2 JPH07110400B2 (en) | 1995-11-29 |
Family
ID=12799848
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3048310A Expired - Fee Related JPH07110400B2 (en) | 1991-03-13 | 1991-03-13 | Plasma heating method and apparatus for molten steel in tundish |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07110400B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2014200779A (en) * | 2013-04-10 | 2014-10-27 | 東芝三菱電機産業システム株式会社 | Particulate generator |
| CN115673304A (en) * | 2022-12-30 | 2023-02-03 | 永红保定铸造机械有限公司 | Device and method for judging molten metal liquid level position through current |
-
1991
- 1991-03-13 JP JP3048310A patent/JPH07110400B2/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2014200779A (en) * | 2013-04-10 | 2014-10-27 | 東芝三菱電機産業システム株式会社 | Particulate generator |
| CN115673304A (en) * | 2022-12-30 | 2023-02-03 | 永红保定铸造机械有限公司 | Device and method for judging molten metal liquid level position through current |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07110400B2 (en) | 1995-11-29 |
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