JPS62267410A - Vacuum refining method for molten metal - Google Patents

Vacuum refining method for molten metal

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Publication number
JPS62267410A
JPS62267410A JP10908486A JP10908486A JPS62267410A JP S62267410 A JPS62267410 A JP S62267410A JP 10908486 A JP10908486 A JP 10908486A JP 10908486 A JP10908486 A JP 10908486A JP S62267410 A JPS62267410 A JP S62267410A
Authority
JP
Japan
Prior art keywords
molten steel
molten metal
molten
level position
metal level
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
Application number
JP10908486A
Other languages
Japanese (ja)
Inventor
Masabumi Ikeda
正文 池田
Osamu Yamase
治 山瀬
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Engineering Corp
Original Assignee
NKK Corp
Nippon Kokan Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by NKK Corp, Nippon Kokan Ltd filed Critical NKK Corp
Priority to JP10908486A priority Critical patent/JPS62267410A/en
Publication of JPS62267410A publication Critical patent/JPS62267410A/en
Pending legal-status Critical Current

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  • Treatment Of Steel In Its Molten State (AREA)

Abstract

PURPOSE:To decarburize a molten metal down to an extra-low carbon region without extending the time for refining by detecting the molten metal level position of the molten metal in a vacuum degassing vessel by a rangefinder and controlling an evacuation device in accordance with the detected value to control the molten metal level position so as to be kept in a prescribed range. CONSTITUTION:The inside of a degassing vessel body 11 is evacuated and maintained under the reduced pressure by operating the evacuation device 40 to rise the molten steel 17 in a ladle 18 into the body 11 via a riser 12. The molten steel is then returned via a downcomer 13 into the ladle 18. The molten steel 17 is decarburized by bringing the oxygen and carbon therein into reaction. Gaseous Ar is blown to the molten steel 17 via a supply pipe 16 to relatively reduce the weight of the molten steel 17 in the riser 16. The molten metal level position of the molten steel 7 is detected by the rangefinder 20 provided in the upper part of the body 11 and the detected value thereof is outputted to a process controller 30 in the above-mentioned operation. The process controller 30 outputs a control signal to the evacuation device 40 in accordance with the signal of the detected value to control the rate of discharge, by which the molten metal level position of the molten steel 17 is feedback-controlled. The molten metal level position is thereby maintained in the prescribed range and the need for extending the time for vacuum refining is eliminated.

Description

【発明の詳細な説明】 [産業上の利用分野] この発明は、真空脱ガス1内の溶)易のフォーミングを
抑制する溶)易の真空精錬方法に関する。
DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for vacuum refining a melt to suppress foaming in the vacuum degassing 1.

[従来の技術1 例えば、Rl−1法等の真空精錬方法においては、排気
装置の排気量か多くなり過ぎると、溶鋼が急激に弱炭さ
れ、これにより発生する一酸化庚素ガス(COガス)に
よって、溶鋼がその湯面付近で激しく発泡する。このよ
うに溶鋼が激しく発泡すると、溶鏑濶面か上昇し、発泡
した溶鋼が排気装置にまで達して装置トラブルを発生さ
せる虞がある。
[Prior art 1] For example, in a vacuum refining method such as the Rl-1 method, if the exhaust volume of the exhaust device becomes too large, the molten steel is rapidly weakened and the resulting carbon monoxide gas (CO gas) is generated. ), the molten steel foams violently near its surface. When the molten steel foams violently in this manner, the surface of the molten steel rises, and the foamed molten steel may reach the exhaust system, causing equipment trouble.

このため、従来、真空槽の上部に設けられた窓から溶鋼
のフォーだングを目視で観察し、排気装置の排気量を調
節して、このフォーミングが激しくなることを防止して
いる。
For this reason, conventionally, the foaming of molten steel is visually observed through a window provided at the top of the vacuum chamber, and the exhaust amount of the exhaust device is adjusted to prevent this forming from becoming severe.

[発明が解決しようとする問題点] しかしながら、この方法の場合には、真空槽の上方から
溶鋼の湯面を観察しているので遠近感をとりにくく、♂
鋼濶面の上下位置を正確に把握することが困難なため、
フォーミングを過剰に抑制せざるを得ない。このフォー
ミングをIIIIIυ1するためには排気装置の排気量
を減少させる必要があるが、この排気量の減少により、
脱炭反応が抑制されてしまう。このため、精錬時間が延
長するという問題点がある。また、排気量を減少させ脱
炭反応を抑制するので7171’lを極低炭素領域まで
脱炭することが困難であるというTA題点がある。更に
、真空槽の上部に設けられた窓から溶!ミを観察する作
業者が必要であり、省力化に反する。
[Problems to be solved by the invention] However, in this method, the surface of the molten steel is observed from above the vacuum chamber, so it is difficult to get a sense of perspective.
Because it is difficult to accurately grasp the vertical position of the steel surface,
Forming has no choice but to be excessively suppressed. In order to achieve this forming, it is necessary to reduce the displacement of the exhaust system, but by reducing this displacement,
The decarburization reaction will be suppressed. Therefore, there is a problem that the refining time is extended. Additionally, there is a TA problem in that it is difficult to decarburize 7171'l to an extremely low carbon range because the exhaust volume is reduced and the decarburization reaction is suppressed. Furthermore, melting can be done through the window provided at the top of the vacuum chamber! This requires a worker to observe the process, which goes against labor-saving measures.

この発明は所かろ事情に鑑みてなされたものであって、
精錬時間が延長せず、極低炭素領域まで脱炭することが
でき、また、溶鋼を観察する作業者が不要の真空精錬方
法を提供することを目的とする。
This invention was made in view of certain circumstances,
The purpose of the present invention is to provide a vacuum refining method that does not extend refining time, can decarburize to an extremely low carbon range, and does not require an operator to observe molten steel.

[問題点を解決するための手段] この発明に係る真空精錬方法は、排気装置により減圧さ
れた真空脱ガス槽内の溶湯の湯面位置を距離計によりI
11定し、この距離計の検出値に基いて排気装置の排気
量を調節してこの湯面位置を所定範囲内に制御すること
を特数とする。
[Means for Solving the Problems] The vacuum refining method according to the present invention measures the surface position of molten metal in a vacuum degassing tank whose pressure is reduced by an exhaust device using a distance meter.
11, and the displacement of the exhaust device is adjusted based on the detected value of the distance meter to control the hot water level position within a predetermined range.

[作用コ この発明においては、真空脱ガス槽内の溶湯の湯面位置
を距離計により測定する。そして、この距離計の値に基
いC排気装置の排気量をUA部してこの湯面(i2置が
所定範囲内に保持されるように湯面位置をフィードバッ
ク制御する。このため、溶湯のフォーミングを過剰に抑
制する必要がなく、また、溶湯を観察する観察者が不要
となる。
[Operations] In this invention, the surface position of the molten metal in the vacuum degassing tank is measured by a distance meter. Then, based on the value of this distance meter, the exhaust amount of the C exhaust device is controlled by the UA section, and the molten metal level position is feedback-controlled so that the molten metal level (i2 position) is maintained within a predetermined range. There is no need to excessively suppress forming, and there is no need for an observer to observe the molten metal.

〔実施例] 以下、添付図面を参照してこの発明の実施例を具体的に
説明する。
[Embodiments] Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings.

第1図はRHEガス設備を示す模式図である。FIG. 1 is a schematic diagram showing RHE gas equipment.

図中10はRH真空脱ガス槽であり、この真空脱ガス槽
1oは、脱ガス槽本体11と、この本体11の下部に設
けられた上昇管12及び下降管13と、本体11の上側
部に設けられた排気管15と、本体11の上部に設けら
れた天窓14とを有している。また、前記真空脱ガスl
f!10の下方には、溶fJ117を貯留した取鍋18
が設置され、前記上昇管12及び下降管13はその下部
が溶鋼17に浸漬されるようになっている。
10 in the figure is an RH vacuum degassing tank, and this vacuum degassing tank 1o includes a degassing tank body 11, an ascending pipe 12 and a descending pipe 13 provided at the lower part of the main body 11, and an upper part of the main body 11. It has an exhaust pipe 15 provided at the top of the main body 11, and a skylight 14 provided at the top of the main body 11. In addition, the vacuum degassing l
f! Below 10 is a ladle 18 in which molten fJ117 is stored.
are installed, and the lower portions of the ascending pipe 12 and the descending pipe 13 are immersed in the molten steel 17.

前記排気管15には、排気¥A置4Qが接続されており
、この排気装置40を作動させることにより脱ガス槽本
体11内を排気して減圧下に保持するようになっている
。そして、このように脱ガス槽本体11内を減圧下に保
持することにより、溶鋼17が説ガス槽本体11内に上
昇し、この溶鋼17内の酸素と炭素とが反応してCOガ
スとなり排気される。
The exhaust pipe 15 is connected to an exhaust system 4Q, and by operating this exhaust system 40, the inside of the degassing tank main body 11 is evacuated and maintained under reduced pressure. By maintaining the inside of the degassing tank main body 11 under reduced pressure in this way, the molten steel 17 rises into the degassing tank main body 11, and the oxygen and carbon in this molten steel 17 react to become CO gas, which is then exhausted. be done.

第2図は排気V5置40を示す構成図である。排気Hi
140は、ブースタポンプ41.42.43と、二連式
エジェクタ44,45.46と、コンデンサ47.48
,49.50とを具備している。
FIG. 2 is a configuration diagram showing the exhaust V5 station 40. Exhaust Hi
140 is a booster pump 41, 42, 43, a double ejector 44, 45, 46, and a capacitor 47, 48
, 49.50.

ブースタポンプ41,42.43は夫々脱ガス槽本体1
1側からこの順番で直列に連結されており、ブースタポ
ンプ41は脱ガス層本体11に接続されている。エジェ
クタ44.45.46は夫々コンデンサ48.49を介
してこの順番で直列に連結されており、エジェクタ44
はコンデンサ47を介してブースタポンプ43に接続さ
れている。
Booster pumps 41, 42, and 43 are respectively connected to the degassing tank main body 1.
They are connected in series in this order from the first side, and the booster pump 41 is connected to the degassing layer main body 11. The ejectors 44, 45, 46 are connected in series in this order via capacitors 48, 49, respectively.
is connected to the booster pump 43 via a capacitor 47.

また、エジェクタ46にはコンデンサ50が接続されて
いる。これらブースタポンプ41.42゜43、及び、
エジェクタ44.45.46を作動させることにより脱
ガス槽本体11内のガスを排気するようになっている。
Further, a capacitor 50 is connected to the ejector 46. These booster pumps 41, 42° 43, and
By operating the ejectors 44, 45, 46, the gas in the degassing tank main body 11 is exhausted.

コンデンサ47.48゜49.50はブースタポンプ4
1.42.43及びエジェクタ44.45.46から排
出されたガスを冷却して排出ガス中の水蒸気を復水させ
ることにより排気するガスの体積を減少させるようにな
っている。
Capacitor 47.48°49.50 is booster pump 4
The volume of the gas to be exhausted is reduced by cooling the gas discharged from the ejectors 44, 45, and 43, and condensing the water vapor in the exhaust gas.

前記上昇管12には、その周面にアルゴンガス(Arガ
ス)供給管16が設けられており、このArガス供給管
16から上昇管12内の溶!A17にArガスを吹込む
ことにより、その部分の溶鋼が相対的に軽くなって上昇
し、下降管13内においては溶鋼17が下降する。そし
て、溶11117が循環し、脱炭反応が均一に進行する
ようになっている。
The riser pipe 12 is provided with an argon gas (Ar gas) supply pipe 16 on its circumferential surface. By blowing Ar gas into A17, the molten steel in that part becomes relatively lighter and rises, and the molten steel 17 descends in the downcomer pipe 13. Then, the melt 11117 is circulated so that the decarburization reaction proceeds uniformly.

前記天窓14の上方にはレーザー距離計20が設置され
ており、このレーザー距離計20により溶1417の湯
面位置を検出するようになっている。
A laser range finder 20 is installed above the skylight 14, and the laser range finder 20 detects the level of the melt 1417.

このレーザー距離計20の原理について第3図を1照し
ながら説明する。光源21から発せられたレーザー光は
、半透鏡24においてその一部が反射して反射鏡22に
達し、この反射鏡22で反射して読取り装置23に違す
る。また、他のレーザー光は半透tJ124を通過して
測定対象物25に達し、ここで反射する。そして、この
レーザー光は半透鏡24で反射して読取り装置23に達
する。
The principle of this laser distance meter 20 will be explained with reference to FIG. A portion of the laser light emitted from the light source 21 is reflected by the semi-transparent mirror 24 and reaches the reflecting mirror 22, and is reflected by the reflecting mirror 22 to be transmitted to the reading device 23. Further, other laser beams pass through the semi-transparent tJ124, reach the measurement object 25, and are reflected there. Then, this laser light is reflected by the semi-transparent mirror 24 and reaches the reading device 23.

ここで、反射鏡22で反射したレーザー光と測定対@’
$J25で反射したレーザー光とに光路差があるので、
読取り装置23において干渉縞が形成される。この干渉
鴫は、反射lA22を移動させることにより移動するが
、この干渉縞の移動に基いて測定対象物25までの距離
を求める。
Here, the laser beam reflected by the reflecting mirror 22 and the measurement pair @'
Since there is an optical path difference between the laser beam reflected by $J25,
Interference fringes are formed in the reading device 23. This interference pattern moves by moving the reflection lA 22, and the distance to the measurement object 25 is determined based on the movement of this interference pattern.

このレーザー距離計20にはプロコン(プロセスを制御
しているコンピュータ)30が接続されており、このプ
ロコン30にレーザー距離計20が検出した値の信号を
出力するようになっている。
A program controller (computer that controls the process) 30 is connected to the laser distance meter 20, and a signal of the value detected by the laser distance meter 20 is output to the program controller 30.

このプロコン30はこの信号に基いて排気装置40に$
11面信9を出力し、バルブ4oの排気量を調節して溶
鋼17の場面位置をフィードバック制御するようになっ
ている。即ち、溶鋼17がフォーミングして溶鋼湯面位
置が高くなった場合には、排気装置40の排気量を減少
させて脱ガス槽本体11内のガス圧を減少させ、溶鋼1
7の湯面位置が低くなった場合には、排気装置40の排
気口を増加させて脱ガス槽本体11内のガス圧を増加さ
せ、溶tA17の場面位置を所定範囲内に保持するよう
になっている。この排気¥R置40の排気量を調節する
ためには、ブースタポンプ41,42゜43、及び、エ
ジェクタ44.45.46のうち作動させるものの数及
び組合わせを調節する。
This pro controller 30 sends $ to the exhaust system 40 based on this signal.
The position of the molten steel 17 is feedback-controlled by outputting the signal 9 from the molten steel 11 and adjusting the displacement of the valve 4o. That is, when the molten steel 17 is formed and the molten steel level rises, the exhaust volume of the exhaust device 40 is reduced to reduce the gas pressure in the degassing tank main body 11, and the molten steel 17 is formed.
When the level of the molten metal 7 becomes low, the number of exhaust ports of the exhaust device 40 is increased to increase the gas pressure in the degassing tank main body 11, and the surface position of the molten tA 17 is maintained within a predetermined range. It has become. In order to adjust the displacement of the exhaust position 40, the number and combination of the booster pumps 41, 42, 43 and ejectors 44, 45, 46 to be activated is adjusted.

次に、この実施例の動作について説明する。先ず、上昇
管12及び下降管13の下部を取鍋18内の溶鋼17に
浸漬し、排気iA置40を作動させて説ガス槽本体11
内を排気する。そして、排気することにより脱ガス槽本
体11内のガス圧が低下していくと、溶鋼17の場面が
上昇すると共に溶鋼17中でCOO20発生し、このC
OO20溶!g17中を浮上して溶鋼17の1面付近で
フォーミングし、このフォーミングガスが排気装置40
に吸引され溶鋼17が脱炭される。また、溶t1417
にArガス供給管16からArガスを供給し、溶鋼17
を循環させ、溶鋼17が均一に脱炭されるようにする。
Next, the operation of this embodiment will be explained. First, the lower parts of the ascending pipe 12 and the descending pipe 13 are immersed in the molten steel 17 in the ladle 18, and the exhaust iA device 40 is activated to remove the gas tank main body 11.
Exhaust the inside. Then, as the gas pressure inside the degassing tank main body 11 decreases by exhausting, the surface of the molten steel 17 rises and COO20 is generated in the molten steel 17.
OO20 melt! g17 and forms near one surface of the molten steel 17, and this forming gas flows into the exhaust device 40.
The molten steel 17 is decarburized. Also, melt t1417
Ar gas is supplied from the Ar gas supply pipe 16 to the molten steel 17.
is circulated so that the molten steel 17 is uniformly decarburized.

この場合に、溶WA17の場面位置をレーザー距離計2
0により検出し、この値の信号に基いてプロコン30に
より排気!l置40の排気量を調節して溶rA17の渇
面位貧が所定範囲内に入るように溶鋼17の場面位置を
制御する。
In this case, the scene position of molten WA17 is determined by the laser distance meter 2.
Detected by 0, and based on the signal of this value, the process controller 30 exhausts the air! The position of the molten steel 17 is controlled so that the exhaust level of the molten steel 17 falls within a predetermined range by adjusting the exhaust amount of the molten steel 17.

このため、脱ガス攪本体11内のCOガス分圧が低下し
てCOO20フォーミングが激しくなり、溶!1417
の湯面が急激に上昇しても、この湯面位置が所定範囲を
超えることが防止される。また、同様に、脱炭反応が過
剰に抑制されて溶!117の湯面が所定範囲よりも低下
することも防止される。
For this reason, the CO gas partial pressure inside the degassing stirring body 11 decreases, and COO20 forming becomes intense, causing melting! 1417
Even if the hot water level rises rapidly, this hot water level position is prevented from exceeding a predetermined range. Similarly, the decarburization reaction is excessively suppressed and melts! It is also prevented that the hot water level of 117 falls below a predetermined range.

従って、従来のように溶鋼のフォーミング、即ち、脱炭
反応を過剰に抑illする必要がないので、真空精錬時
間が延長することがない。また、これに伴い、真空精錬
時間を一定にしても脱炭量が低下することがないので、
溶鋼中の酸素濃度を少なくすることができ、脱酸剤とし
て添加するアルミニウムの量が増加することがない。更
に、脱炭反応を抑制する必要がないので、極低炭素領域
まで脱炭することができる。更にまた、溶鋼、場面を自
動制御するので溶3メを観察する作業者が不要となる。
Therefore, there is no need to excessively suppress the forming of molten steel, that is, the decarburization reaction, as in the conventional method, so that the vacuum refining time is not extended. Additionally, as a result, the amount of decarburization does not decrease even if the vacuum refining time is kept constant.
The oxygen concentration in molten steel can be reduced, and the amount of aluminum added as a deoxidizing agent does not increase. Furthermore, since there is no need to suppress the decarburization reaction, decarburization can be carried out to an extremely low carbon range. Furthermore, since the molten steel and the scene are automatically controlled, there is no need for an operator to observe the molten metal.

なお、この実施例においては、RH法の場合を示したが
、これに限らず他の真空精錬方法にも適用することがで
きる。また、この実施例においては、レーザー距離計を
使用したが、これに限らず、例えば渦流距離計等、他の
距離計を使用することもできる。
In addition, although the case of the RH method was shown in this Example, it is not limited to this and can be applied to other vacuum refining methods. Further, in this embodiment, a laser distance meter is used, but the present invention is not limited to this, and other distance meters such as an eddy current distance meter can also be used.

[発明の効果コ この発明によれば、真空脱ガス槽内の溶鋼の場面位置を
距離計により検出し、この値に塁き、排気装置の排気量
を調節して、場面位置が所定範囲に保持されるように場
面位置をフィードバック制御する。このため、溶湯のフ
ォーミングを過剰に抑制する必要がなく、脱炭反応が抑
制されないので、真空精錬時間が延長することがない。
[Effects of the Invention] According to this invention, the position of the molten steel in the vacuum degassing tank is detected by a distance meter, and based on this value, the exhaust volume of the exhaust device is adjusted to bring the position of the molten steel within a predetermined range. The scene position is feedback-controlled so that it is maintained. Therefore, there is no need to excessively suppress the forming of the molten metal, and since the decarburization reaction is not suppressed, the vacuum refining time is not extended.

また、脱炭反応を抑制することがないので、橘低炭素領
域まで溶湯を真空量線することができる。更に、溶鋼の
場面位置を自動制御するので、溶鋼を1q察する作業者
が不要となる。
Furthermore, since the decarburization reaction is not suppressed, the molten metal can be vacuum dosed to the Tachibana low carbon region. Furthermore, since the position of the molten steel is automatically controlled, there is no need for an operator to inspect 1q of molten steel.

【図面の簡単な説明】[Brief explanation of drawings]

第1図はRHIIRガス設備を示す模式図、第2図は排
気装置を示す構成図、第3図はレーザー距離計の原理を
示す模式図である。 10;真空脱ガス槽、17:♂鋼、20:距餠計、30
:プロコン、40:排気装置 出願人代理人 弁理士 鈴江武彦 第1図
FIG. 1 is a schematic diagram showing the RHIIR gas equipment, FIG. 2 is a configuration diagram showing the exhaust system, and FIG. 3 is a schematic diagram showing the principle of the laser distance meter. 10; Vacuum degassing tank, 17: Male steel, 20: Distance meter, 30
:Procon, 40: Exhaust system applicant's agent Patent attorney Takehiko Suzue Figure 1

Claims (1)

【特許請求の範囲】[Claims] 排気装置により減圧された真空脱ガス槽内の溶湯の湯面
位置を距離計により測定し、この距離計の検出値に基い
て排気装置の排気量を調節してこの湯面位置を所定範囲
内に制御することを特徴とする溶湯の真空精錬方法。
The surface position of the molten metal in the vacuum degassing tank, which has been depressurized by the exhaust device, is measured with a distance meter, and the exhaust amount of the exhaust device is adjusted based on the detected value of this distance meter, so that the surface position of the molten metal is within a predetermined range. A vacuum refining method for molten metal characterized by controlling the molten metal.
JP10908486A 1986-05-13 1986-05-13 Vacuum refining method for molten metal Pending JPS62267410A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10908486A JPS62267410A (en) 1986-05-13 1986-05-13 Vacuum refining method for molten metal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10908486A JPS62267410A (en) 1986-05-13 1986-05-13 Vacuum refining method for molten metal

Publications (1)

Publication Number Publication Date
JPS62267410A true JPS62267410A (en) 1987-11-20

Family

ID=14501190

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10908486A Pending JPS62267410A (en) 1986-05-13 1986-05-13 Vacuum refining method for molten metal

Country Status (1)

Country Link
JP (1) JPS62267410A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008524441A (en) * 2004-12-20 2008-07-10 エドワーズ リミテッド Method for degassing molten metal

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008524441A (en) * 2004-12-20 2008-07-10 エドワーズ リミテッド Method for degassing molten metal

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