JP2718096B2 - Vacuum cleaning method for molten metal - Google Patents
Vacuum cleaning method for molten metalInfo
- Publication number
- JP2718096B2 JP2718096B2 JP25080688A JP25080688A JP2718096B2 JP 2718096 B2 JP2718096 B2 JP 2718096B2 JP 25080688 A JP25080688 A JP 25080688A JP 25080688 A JP25080688 A JP 25080688A JP 2718096 B2 JP2718096 B2 JP 2718096B2
- Authority
- JP
- Japan
- Prior art keywords
- molten metal
- gas
- bubbling
- pressure
- inclusions
- 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 - Lifetime
Links
- 239000002184 metal Substances 0.000 title claims description 44
- 229910052751 metal Inorganic materials 0.000 title claims description 44
- 238000000034 method Methods 0.000 title claims description 33
- 238000010407 vacuum cleaning Methods 0.000 title claims 2
- 239000007789 gas Substances 0.000 claims description 39
- 230000005587 bubbling Effects 0.000 claims description 20
- 238000007872 degassing Methods 0.000 claims description 11
- 238000004140 cleaning Methods 0.000 claims description 7
- 238000007667 floating Methods 0.000 claims description 7
- 239000011261 inert gas Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 2
- 238000003756 stirring Methods 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 description 16
- 239000010959 steel Substances 0.000 description 16
- 230000006837 decompression Effects 0.000 description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 238000012545 processing Methods 0.000 description 6
- 239000000047 product Substances 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 239000002436 steel type Substances 0.000 description 3
- 229910000975 Carbon steel Inorganic materials 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 239000010962 carbon steel Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 229910004261 CaF 2 Inorganic materials 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Landscapes
- Continuous Casting (AREA)
- Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 この発明は、溶融金属中に浮遊する介在物を除去する
溶融金属の減圧清浄化方法に関する。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning a molten metal under reduced pressure for removing inclusions floating in the molten metal.
溶融金属中に浮遊する介在物（例えば溶鋼中のアルミ
ナ系介在物）は、系外に除去されずに金属が凝固してし
まうと、製品品質欠陥の原因となるため、その低減・除
去方法が種々提案されている。Inclusions floating in the molten metal (for example, alumina-based inclusions in molten steel) can cause product quality defects if the metal solidifies without being removed outside the system. Various proposals have been made.
その中で比較的効率が良いとして多用されている方法
に、常圧下で浴面下から溶融金属中に不活性ガスをバブ
リングすることで、ガス気泡に介在物をトラップさせ、
浮上後これを除去する方法がある（以下、従来法とい
う）。Among them, a method that is often used as relatively efficient is to trap an inclusion in gas bubbles by bubbling an inert gas into the molten metal from below the bath surface under normal pressure,
There is a method of removing this after floating (hereinafter referred to as a conventional method).
ところが、高級材製造を目的とした場合、溶鋼中のト
ータル酸素量は15ppm以下に抑える必要があるが、上記
の方法によってはこのような溶融金属の超清浄化を達成
し得ないという問題があり、新たな手段の開発が望まれ
ていた。However, for the purpose of manufacturing high-grade materials, the total oxygen content in molten steel must be suppressed to 15 ppm or less, but there is a problem that such ultra-cleaning of molten metal cannot be achieved by the above method. The development of new means was desired.
即ち、従来のガスバブリング法では、バブリング領域
が容器底面のガス吹込み口から上方に摺り鉢状に広がる
領域だけであり、しかも吹込み方法の制約から容器全域
からバブリングすることは難しいという問題があった。
又、バブリングによりできる気泡の大きさが大きいとい
うことが原因となり、該気泡が浮上する際、溶融金属は
その周りを迂回するように流れ、その流れと一緒に微細
介在物もこの気泡を避けて移動するため、微細介在物は
気泡にトラップされにくいといった問題もある。That is, the conventional gas bubbling method has a problem that the bubbling region is only a region extending upward from the gas inlet on the bottom of the container in a mortar-like shape, and it is difficult to bubble from the entire container due to the restriction of the blowing method. there were.
Also, due to the large size of the bubble formed by bubbling, when the bubble floats, the molten metal flows so as to bypass it, and along with the flow, fine inclusions also avoid this bubble. There is also a problem that the fine inclusions are hard to be trapped by bubbles due to the movement.
そのため本発明者等は、次のような提案を行なった
（特願昭62−326722号）。その提案内容は、加圧状態に
した溶融金属を、それに可溶なガスでバブリングして該
溶融金属中にガスを溶解せしめ、その後急速に減圧して
溶融金属中に微細ガス気泡を発生させ、溶融金属中に浮
遊する介在物をバブリングによるガス気泡及び減圧によ
り発生した微細ガス気泡にトラップせしめて、浮上後こ
れを除去するというものである（以下、この方法を加圧
減圧法という）。Therefore, the present inventors have made the following proposal (Japanese Patent Application No. 62-326722). The content of the proposal is to melt the gas in the molten metal in a pressurized state by bubbling with a gas soluble in the molten metal, and then rapidly reduce the pressure to generate fine gas bubbles in the molten metal, Inclusions floating in the molten metal are trapped in gas bubbles by bubbling and fine gas bubbles generated by depressurization, and are removed after floating (hereinafter, this method is referred to as pressurization and decompression method).
溶融金属中の通常の介在物は最初のバブリングでトラ
ップされ浮上せしめられることになる。他方、このバブ
リングは加圧した溶融金属に対して行なわれるため、バ
ブリングガスが多量に溶融金属中に溶け込むことにな
る。その後の急速な減圧で、溶融金属中に溶け込んでい
たガスが微細なガス気泡となって溶融金属全域から発生
する。この時、微細な介在物は該ガス気泡にトラップさ
れて浮上する。Ordinary inclusions in the molten metal will be trapped and lifted in the first bubbling. On the other hand, since the bubbling is performed on the pressurized molten metal, a large amount of the bubbling gas dissolves into the molten metal. Then, by rapid decompression, the gas dissolved in the molten metal becomes fine gas bubbles and is generated from the entire molten metal. At this time, the fine inclusions are trapped by the gas bubbles and float.
このような溶融金属中の介在物を除去するには、極め
て効率の良い優れた方法ではあるが、処理工程の最初の
段階で溶融金属を加圧状態にしているため、減圧後の放
置時間が短い場合、一旦溶融金属中に溶け込んだバブリ
ングガスは、減圧時にその一部が微細ガス気泡となって
現われるものの、残りは溶融金属中に依然溶け残ったま
まの状態となる。従って上記処理後に更に脱ガスを行な
う別処理工程が必要となり、該脱ガスのために設備増強
や処理工数の増加が問題となっていた。又、加圧容器を
使用するため設備コスト等も高くつくといった別の問題
もある。Although it is an extremely efficient and excellent method to remove such inclusions in the molten metal, since the molten metal is pressurized in the first stage of the treatment process, the standing time after decompression is reduced. If the length is short, the bubbling gas once dissolved in the molten metal will appear as fine gas bubbles when the pressure is reduced, but the rest will remain dissolved in the molten metal. Therefore, a separate processing step for further degassing after the above-mentioned processing is required, and there has been a problem that the degassing requires an increase in equipment and an increase in the number of processing steps. In addition, there is another problem that equipment costs and the like are high because a pressurized container is used.
本発明は、以上のような問題に鑑み創案されたもの
で、圧力調整を伴う上記のバブリング方法（加圧減圧
法）を改良し、加圧容器を使用せず、しかも上記したよ
うな脱ガス工程を省くことができるようにしようとする
ものである。The present invention has been made in view of the above problems, and is an improvement of the above-described bubbling method (pressure decompression method) involving pressure adjustment, which does not use a pressurized container, and has the above-described degassing method. It is intended to be able to omit the process.
そのため本発明は、既提案の溶融金属の清浄化方法の
うち最初に行なっていた溶融金属の加圧処理を止め、該
溶融金属に対して大気圧もしくはそれ以下の状態で、そ
れに可溶なガスをバブリングし、その後に減圧処理を行
なう。特にこの減圧処理では、単に微細ガス気泡を発生
させるだけでなく、溶融金属中に溶け残っている前記バ
ブリングガスも一緒に脱ガス、鋼中に残存させないよう
にすることになる。Therefore, the present invention stops the pressurizing treatment of the molten metal, which was first performed in the proposed method of cleaning the molten metal, and releases the gas soluble in the molten metal at atmospheric pressure or lower. , Followed by a decompression treatment. In particular, in this decompression treatment, not only the fine gas bubbles are generated, but also the bubbling gas remaining in the molten metal is degassed together with the gas so as not to remain in the steel.
これは、大気圧もしくはそれ以下の状態での溶解処理
でも、清浄化の効果が得られ、さらに鋼中に残存するガ
スについては加圧減圧法による場合に比べ少なくするこ
とが容易なためである。又、可溶ガスの雰囲気分圧だけ
でなく、溶融金属の種類・成分によってもガスの溶解量
は決まるので、成分系の違いにより大気圧もしくはそれ
以下の状態でも加圧した場合より溶解ガス量が多くなる
場合がある。例えば、溶融金属として溶鋼、可溶性ガス
として窒素を用いた場合、飽和状態で通常の炭素鋼で
は、窒素の大気圧下では約400ppm、10気圧下で約1400pp
m溶解するが、18％Crを含有する場合、大気圧で約2500p
pm溶解する。従って、このような鋼種では大気圧下でも
加圧した場合と同等の効果が期待される。This is because the effect of cleaning can be obtained even in the melting treatment at atmospheric pressure or lower, and the gas remaining in the steel can be easily reduced as compared with the case of the pressure reduction method. . In addition, the amount of dissolved gas is determined not only by the atmospheric partial pressure of the soluble gas, but also by the type and composition of the molten metal. May increase. For example, when molten steel is used as a molten metal and nitrogen is used as a soluble gas, in a saturated state, ordinary carbon steel is about 400 ppm under nitrogen atmospheric pressure and about 1400 pp under 10 atmospheres.
dissolves but contains 18% Cr, about 2500p at atmospheric pressure
Dissolve pm. Therefore, with such a steel type, the same effect as when pressurizing even under atmospheric pressure is expected.
但し、溶融金属浴の浴深が深い程、溶融金属に静圧が
かかるため、減圧時に浴深部における脱ガスを行なうこ
とが難しくなる。このような場合は、溶融金属に不活性
ガスをバブリングして該溶融金属を撹拌せしめること
で、減圧による脱ガスを効率良く行なわしめるようにす
ると良い。However, the deeper the bath depth of the molten metal bath, the more the static pressure is applied to the molten metal. Therefore, it is difficult to perform degassing in the bath depth at the time of pressure reduction. In such a case, degassing by depressurization may be efficiently performed by bubbling an inert gas to the molten metal and stirring the molten metal.
第１図は、本発明法を溶鋼で実施した場合にバブリン
グを行なう最初の処理の際の容器内圧力（Pstart）と、
減圧処理を行なう後の処理工程における容器内圧力（Pe
nd）を座標に採って、処理後に得られる溶融金属中の介
在物Ｔ・〔Ｏ〕と可溶ガスとして窒素を用いた場合の最
終〔Ｎ〕の量を調べて各々の低減度合から領域に分けて
示したものである。図中、交差する線Ａで示した領域
は、上記介在物が減少し、且つ通常の鋼種の場合、最終
〔Ｎ〕が最終製品に与える影響が少なく問題とならない
本発明法による領域を示している。又、斜線Ｂで示した
領域は、該介在物は減少するが、最終〔Ｎ〕が問題とな
る場合がある領域であり、鋼種によっては、この処理後
新たに脱Ｎを行なう工程が必要となる。尚、以下に示す
実施例１で行なった本発明法は同グラフ図中●（黒点）
で示した所で行なわれたことになる。FIG. 1 shows the pressure (Pstart) in the vessel at the time of the first treatment for bubbling when the method of the present invention is carried out with molten steel,
The pressure inside the vessel (Pe
Using nd) as coordinates, the amount of inclusions T • [O] in the molten metal obtained after the treatment and the final [N] in the case of using nitrogen as a soluble gas is examined, and the amount of reduction is determined based on the degree of each reduction. It is shown separately. In the figure, the area indicated by the intersecting line A indicates the area according to the method of the present invention in which the inclusions are reduced and the final [N] has little effect on the final product in the case of a normal steel type. I have. The region indicated by the oblique line B is a region where the inclusions are reduced, but the final [N] may be a problem. Depending on the type of steel, it is necessary to perform a step of newly removing N after this treatment. Become. Note that the method of the present invention performed in Example 1 shown below is indicated by ● (black dots) in the graph.
That is, it was performed at the place indicated by.
〔実施例１〕 以下本発明法の具体的実施例につき説明する。Example 1 Hereinafter, a specific example of the method of the present invention will be described.
最初に本発明者等は、50tonVOD設備内で50ton溶鋼を1
660℃で300torrに保ち、取鍋上部よりランスを用いて10
分間で6Nm3のN2ガスを吹き込んだ。その後VAD設備内に
該用鋼を移し熱補償を行ないながら３分で1torrまで減
圧させ20分間保持した。この時、同時に取鍋底部からAr
ガスを150Nl/minでバブリングした。First, the present inventors set 50 tons of molten steel in a 50 ton VOD facility.
Keep at 300 torr at 660 ° C and use a lance from the top of the ladle
For 6 minutes, 6Nm 3 of N 2 gas was blown. After that, the steel was transferred into a VAD facility, and the pressure was reduced to 1 torr in 3 minutes and maintained for 20 minutes while performing thermal compensation. At this time, Ar
The gas was bubbled at 150 Nl / min.
又、従来のArガスバブリング法と、N2ガスバブリング
時に加圧状態にして行なう既提案に係る加圧減圧法を上
記実験と共に実施した。そのうち従来法は50tonの溶鋼
を真空取鍋内で0.5〜1torrに維持したまま取鍋底部より
Arガスを150Nl/minの吹込み速度で20分間バブリングし
たものである。又、加圧減圧法はN2ガス吹込み時に３気
圧まで加圧し、その後の減圧処理時には0.5torrまで減
圧することにより行なわれるもので、その他は本発明法
と同様な条件で処理された。但し減圧処理後における脱
ガス処理は行なっていない。In addition, a conventional Ar gas bubbling method and a pressurized depressurization method according to a previously proposed method in which a pressurized state is applied during N 2 gas bubbling were carried out together with the above experiment. In the conventional method, 50 tons of molten steel is maintained in a vacuum ladle at 0.5 to 1 torr from the bottom of the ladle.
Ar gas was bubbled at a blowing rate of 150 Nl / min for 20 minutes. The pressurizing and depressurizing method is carried out by increasing the pressure to 3 atm when N 2 gas is blown and reducing the pressure to 0.5 torr during the subsequent depressurizing treatment, and the other conditions are the same as those of the present invention. However, degassing after the decompression was not performed.
以上の３法を実施した時の溶鋼正文とT.〔Ｏ〕及びＴ
・〔Ｎ〕の成分変化を下記第１表に示す。Molten steel, T. [O] and T
Table 1 below shows the component changes of [N].
上記表からも明らかなように、本発明法は加圧減圧法
と概略同程度に処理時間20分間でＴ・〔Ｏ〕レベル８〜
9ppmが得られており、溶鋼中の介在物の除去がなされて
いることがわかる。しかもその後に脱ガス処理を行なわ
なくても溶鋼中のN2ガスは31ppmとなり製品上問題とな
らないレベルに十分に低減せしめられていることがわか
る。 As is clear from the above table, the method of the present invention has a T. [O] level of 8 to
9 ppm was obtained, which indicates that the inclusions in the molten steel were removed. Moreover, it can be seen that the N 2 gas in the molten steel is 31 ppm even if the degassing process is not performed thereafter, and the N 2 gas is sufficiently reduced to a level that does not cause a problem in the product.
〔実施例２〕 次に同じ50tonVAD/VOD設備を用い抄紙機用SUS316ステ
ンレス鋼板に適用した。ステンレス鋼の場合、Cr含有量
が高いため、炭素鋼より溶鋼中に固溶する飽和〔Ｎ〕量
が多い。1660℃でバブリングランスを用いて28分間で41
m3のN2ガスを吹込んだ。炉内雰囲気圧は実施例１と同様
で大気圧である。その後スラグ組成が、CaO＋CaF2＝65
〜80％、SiO2＝５〜20％、MgO＝２〜10％、Al2O3≦３％
となるように調整した後、３分間で1torrまで減圧し、3
5分間保持した。この時、同時に取鍋底部からArガスを1
50／分の流量で吹込んだ。[Example 2] Next, the same 50 ton VAD / VOD equipment was used to apply to a SUS316 stainless steel sheet for a paper machine. In the case of stainless steel, since the Cr content is high, the amount of saturated [N] dissolved in molten steel is larger than that of carbon steel. 1660 ° C with bubbling lance for 41 minutes in 28 minutes
m 3 N 2 gas was blown. The atmosphere pressure in the furnace is the same as that in Example 1 and is atmospheric pressure. After that, the slag composition becomes CaO + CaF 2 = 65
~80%, SiO 2 = 5~20% , MgO = 2~10%, Al 2 O 3 ≦ 3%
After reducing the pressure to 1 torr in 3 minutes,
Hold for 5 minutes. At this time, Ar gas was simultaneously injected from the bottom of the ladle.
Injected at a flow rate of 50 / min.
この時の成分の挙動を下記第２表に示す。温度は1620
℃から1575℃まで変化した。従来法を比較対象として示
すが、この鋼種は介在物が後工程で疵となる可能性があ
り、それを防止するため、従来は脱酸時間を長くとって
いた。The behavior of the components at this time is shown in Table 2 below. Temperature is 1620
C. to 1575 ° C. Although the conventional method is shown as a comparative object, this steel type has a possibility that inclusions may become flaws in a later process, and in order to prevent this, conventionally, a long deoxidation time was taken.
このように本発明により従来より短時間で（90分→35
分）、より低いＴ・〔Ｏ〕レベル（30ppm→20ppm）が到
達でき、しかもその後に脱ガス処理を行なわなくても溶
鋼中の〔Ｎ〕は十分低減している。Thus, according to the present invention, it is possible to reduce the time (90 minutes → 35
Min.), A lower T. [O] level (30 ppm → 20 ppm) can be reached, and [N] in the molten steel is sufficiently reduced even without subsequent degassing.
復圧処理後7ton上広鋼塊に鋳造し、圧延を経て厚板製
品とした。製品表面を鏡面仕上げして目視観察により製
品の清浄度を評価する地疵については、内在する介在物
に起因するものが多い。After the decompression treatment, it was cast into a 7-ton steel ingot and rolled to obtain a thick plate product. Many ground flaws, which are used to mirror-finish the product surface and visually evaluate the cleanliness of the product by visual observation, are caused by internal inclusions.
第２図に示すように地疵指数は、従来100に対して本
法適用により50以下に減少し、顕著な効果がみられた。
これは本発明により地疵の原因となる介在物が減少した
ためである。As shown in FIG. 2, the flaw index was reduced to 50 or less by applying this method to the conventional 100, and a remarkable effect was observed.
This is because the inclusions causing the ground flaw were reduced by the present invention.
〔発明の効果〕 以上詳述したように本発明の減圧清浄化方法によれ
ば、溶融金属中の介在物が十分に除去されることになる
と共に、加圧処理を行なっていないため加圧容器を必要
とせず、且つ減圧時に脱ガスも十分になされるため、そ
の後脱ガスを別処理工程として行なう必要がなくなつ
て、該処理設備の増設を不要とすることができ、又、そ
の分処理工数も減らすことが可能となる等、優れた効果
を有している。 [Effects of the Invention] As described above in detail, according to the reduced pressure cleaning method of the present invention, inclusions in the molten metal are sufficiently removed, and the pressure vessel is not subjected to the pressure treatment. And degassing is sufficiently performed at the time of depressurization, so that it is not necessary to perform degassing as a separate processing step thereafter, so that it is not necessary to increase the number of the processing equipment, and the processing It has excellent effects, such as a reduction in man-hours.
第１図は本発明法を実施した場合に最初に行なわれた処
理の際の容器内圧力と、その後の減圧処理時の容器内圧
力を座標に採り、処理後に得られる溶融金属中の介在物
と最終〔Ｎ〕の量を調べて示したグラフ図、第２図はSU
S316製品に本法を適用した場合の地疵の減少を示したグ
ラフ図である。FIG. 1 shows the pressure in the vessel at the time of the first treatment when the method of the present invention is carried out, and the pressure in the vessel at the time of the subsequent depressurization treatment in coordinates, and inclusions in the molten metal obtained after the treatment. Fig. 2 is a graph showing the amount of final [N].
FIG. 4 is a graph showing a reduction in ground flaws when the present method is applied to an S316 product.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 松野 秀寿 東京都千代田区丸の内１丁目１番２号 日本鋼管株式会社内 (56)参考文献 特開 平１−170556（ＪＰ，Ａ) 特公 昭58−48609（ＪＰ，Ｂ２) ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hidetoshi Matsuno 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. −48609 (JP, B2)
Claims (2)
をそれに可溶なガスでバブリングして該溶融金属中にガ
スを溶解せしめ、その後急速に減圧して溶融金属中に微
細ガス気泡を発生させると共に、この減圧で該溶融金属
中に溶け残っているバブリングガスの脱ガスを合わせて
行ない、溶融金属中に浮遊する介在物をバブリングによ
るガス気泡及び減圧により発生した微細ガス気泡にトラ
ップせしめて、浮上後これを除去することを特徴とする
溶融金属の減圧清浄化方法。1. Bubbling a molten metal with a gas soluble in the molten metal at atmospheric pressure or lower to dissolve the gas in the molten metal, and then reduce the pressure rapidly to generate fine gas bubbles in the molten metal. At the same time, degassing of the bubbling gas remaining in the molten metal at this reduced pressure is also performed, and inclusions floating in the molten metal are trapped by gas bubbles generated by bubbling and fine gas bubbles generated by the reduced pressure. And a method of cleaning molten metal under reduced pressure, comprising removing the material after floating.
施するに当り、溶融金属中に不活性ガスをバブリングせ
しめて該溶融金属を撹拌しながら急速に減圧せしめるこ
とを特徴とする溶融金属の減圧清浄化方法。2. A method for cleaning a molten metal under reduced pressure according to the above-mentioned item, wherein an inert gas is bubbled into the molten metal, and the molten metal is rapidly depressurized while stirring. Vacuum cleaning method.
Priority Applications (9)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25080688A JP2718096B2 (en) | 1988-10-06 | 1988-10-06 | Vacuum cleaning method for molten metal |
| CA000614559A CA1339703C (en) | 1988-10-06 | 1989-09-29 | Method for cleaning molten metal |
| AU42457/89A AU4245789A (en) | 1988-10-06 | 1989-10-02 | Method for cleaning molten metal |
| BR898905068A BR8905068A (en) | 1988-10-06 | 1989-10-05 | METAL FUSION CLEANING PROCESS |
| DE8989118517T DE68905741T2 (en) | 1988-10-06 | 1989-10-05 | METHOD FOR CLEANING METAL. |
| EP89118517A EP0362851B1 (en) | 1988-10-06 | 1989-10-05 | Method for cleaning molten metal |
| KR1019890014420A KR920006578B1 (en) | 1988-10-06 | 1989-10-06 | Method for selecting molten metal |
| US07/516,478 US5091000A (en) | 1987-12-25 | 1990-04-30 | Method for cleaning molten metal and apparatus therefor |
| AU13976/92A AU655245B2 (en) | 1988-10-06 | 1992-04-02 | Method for cleaning molten metal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25080688A JP2718096B2 (en) | 1988-10-06 | 1988-10-06 | Vacuum cleaning method for molten metal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0299263A JPH0299263A (en) | 1990-04-11 |
| JP2718096B2 true JP2718096B2 (en) | 1998-02-25 |
Family
ID=17213325
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP25080688A Expired - Lifetime JP2718096B2 (en) | 1987-12-25 | 1988-10-06 | Vacuum cleaning method for molten metal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2718096B2 (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5848609B2 (en) | 2009-11-13 | 2016-01-27 | 株式会社カネカ | Resin composition for paint |
-
1988
- 1988-10-06 JP JP25080688A patent/JP2718096B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5848609B2 (en) | 2009-11-13 | 2016-01-27 | 株式会社カネカ | Resin composition for paint |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0299263A (en) | 1990-04-11 |
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