JPH01181953A - Apparatus for cleaning molten metal - Google Patents
Apparatus for cleaning molten metalInfo
- Publication number
- JPH01181953A JPH01181953A JP685488A JP685488A JPH01181953A JP H01181953 A JPH01181953 A JP H01181953A JP 685488 A JP685488 A JP 685488A JP 685488 A JP685488 A JP 685488A JP H01181953 A JPH01181953 A JP H01181953A
- Authority
- JP
- Japan
- Prior art keywords
- molten metal
- container
- vessel
- gas
- bubbling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000002184 metal Substances 0.000 title claims abstract description 45
- 238000004140 cleaning Methods 0.000 title claims abstract description 11
- 230000005587 bubbling Effects 0.000 claims description 19
- 238000002347 injection Methods 0.000 claims 1
- 239000007924 injection Substances 0.000 claims 1
- 230000008018 melting Effects 0.000 claims 1
- 238000002844 melting Methods 0.000 claims 1
- 238000000034 method Methods 0.000 abstract description 16
- 238000007664 blowing Methods 0.000 abstract description 7
- 239000007789 gas Substances 0.000 description 38
- 229910000831 Steel Inorganic materials 0.000 description 16
- 239000010959 steel Substances 0.000 description 16
- 238000000605 extraction Methods 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 229910052582 BN Inorganic materials 0.000 description 1
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 239000010812 mixed waste Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 230000002747 voluntary effect Effects 0.000 description 1
Abstract
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
融金属の清浄化装置に関するＯ
〔従来の技術〕
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、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。[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a molten metal cleaning device for removing inclusions floating in molten metal. [Prior Art] Inclusions floating in molten metal Since alumina-based inclusions (for example, alumina-based inclusions in molten steel) cause product quality defects, various methods for reducing and removing them have been proposed.
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
、常圧下で容器の底から溶融金属中に不活性ガスをバブ
リングすることにより、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。 。Among these, a method that is often used as it is relatively efficient is to bubble inert gas into the molten metal from the bottom of the container under normal pressure to trap inclusions in the gas bubbles and remove them after floating. There is a way to do it. .
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１０ ｐｐｍ以下に抑える必要がある。しかし、上記
の方法によってはこのような溶融金属の超清浄化の要請
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。If the purpose is to manufacture high-grade materials, the total amount of oxygen in molten steel must be suppressed to 10 ppm or less. However, there is a problem in that the above-mentioned methods cannot meet the requirement for ultra-cleaning of molten metal, and there has been a desire to develop a new method.
即ち、従来のが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すり林状に広がる領
域だけであり、しかも吹込み方法の制約から容器全域か
らパブリングすることは難しいという問題があった。In other words, in the conventional bubbling method, the bubbling area is limited to an area that spreads upward from the gas inlet at the bottom of the container in a forest-like manner, and furthermore, it is difficult to bubble from the entire area of the container due to restrictions on the bubbling method. was there.
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、その流れといっしょに微
細介在物は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。Another cause is that the bubbles formed by bubbling are large, and when the bubbles float up, the molten metal flows around them, and the fine inclusions move along with the flow, avoiding the bubbles. Therefore, there is also the problem that fine inclusions are difficult to be trapped by air bubbles.
そのため本発明者等は、本件出願と略同時に、上記の問
題を解決するための提案を行なった。その提案の内容は
、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。Therefore, the present inventors made a proposal to solve the above problem almost at the same time as filing the present application. The proposal involves bubbling molten metal under pressure with a soluble gas to dissolve the gas in the molten metal, and then rapidly reducing the pressure to generate fine gas bubbles in the molten metal. In this method, inclusions floating in molten metal are trapped in gas bubbles caused by bubbling and fine gas bubbles generated by reduced pressure, and are removed after floating.
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
プされて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、可
溶なバブリングガスが多量に溶融金属中に溶は込むこと
になる。その後の急速な減圧で、溶融金属中に溶は込ん
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。Normal inclusions in the molten metal will be trapped and brought to the surface by the initial bubbling. On the other hand, since this bubbling is performed on the pressurized molten metal, a large amount of soluble bubbling gas melts into the molten metal. The subsequent rapid depressurization causes the gas that had entered the molten metal to become fine gas bubbles that are generated from the entire area of the molten metal. At this time, fine inclusions are trapped by the gas bubbles and float up.
このように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、その方法を実施する
装置として最初に用いられたものは、第３図に示すよう
な二つの容器（１００ＸＩＯＩ）からなる構成であった
。即ち、容器（１００）を加圧容器として用い、この中
に溶融金属（３）を入れた上で内部雰囲気をＡｒガスに
置換せしめると共に、容器（１００）底部からＡｒガス
（加圧及びバブリング用のガス）と溶融金属（３）に可
溶なガス（例えばＨ２ガス）との混合ガスをバブリング
する。そして、この容器（期）内の加圧とバブリングを
止め、ストッパ（２００）を開放することで溶融金属（
３）を隣りの容器Ｑｏｌ）に移す。その後該容器（１０
１）を減圧容器として用と１、調圧弁（１０１＄Ｌ）に
よって容器（１０１）の内部雰囲気を急速に減圧（大気
圧まで）せしめる。Although this is an extremely efficient and excellent method for removing inclusions in molten metal, the equipment that was first used to carry out the method was two devices as shown in Figure 3. The structure consisted of a container (100XIOI). That is, the container (100) is used as a pressurized container, the molten metal (3) is put therein, the internal atmosphere is replaced with Ar gas, and Ar gas (for pressurization and bubbling) is supplied from the bottom of the container (100). (gas) and a gas (for example, H2 gas) soluble in the molten metal (3) is bubbled. Then, by stopping the pressurization and bubbling in this container (stage) and opening the stopper (200), the molten metal (
Transfer 3) to the adjacent container Qol). Then the container (10
1) is used as a pressure reducing container, and the internal atmosphere of the container (101) is rapidly reduced in pressure (to atmospheric pressure) using a pressure regulating valve (101$L).
すると、微細ガス気泡が多量に発生するため。As a result, a large amount of fine gas bubbles are generated.
、これにトラップされて浮上してきた介在物を除去する
。, to remove inclusions that have been trapped and floated up.
上記装置に用いられるストッパ（２００）は、窒化ホウ
素やジルコニア系又はアルミナ系の耐化物が用いられ、
−回の実施で使用不能になる。そのため、実施毎に該ス
トッパ（２００）の交換が必要となり、メンテナンスに
多くの時間と手間が掛かる・又溶融金属（３）が滲出て
ストッパ（２００）を開口に溶着せしめてしまうという
こともあり、該ストッパ（２００）の開放が不可能にな
るという事故が起きることも多い。The stopper (200) used in the above device is made of boron nitride, zirconia, or alumina-based resistant material,
- It becomes unusable after being implemented twice. Therefore, the stopper (200) needs to be replaced every time it is used, which requires a lot of time and effort for maintenance.Moreover, the molten metal (3) may leak out and weld the stopper (200) to the opening. , accidents often occur in which the stopper (200) becomes impossible to open.
本発明はこのような問題に鑑み創案されたもので、これ
らの問題のない当該方法の実施に最適な装置を提供しよ
うとするものである。The present invention was devised in view of these problems, and aims to provide an apparatus that is most suitable for implementing the method without these problems.
そのため本発明の装置は、第１図に示されるように密閉
容器（ｌａ）Ｑｂ）を上下二段に重ねて、これらの間を
細管（２）でつないだもので構成される。Therefore, as shown in FIG. 1, the apparatus of the present invention is constructed by stacking closed containers (la) and Qb) in two layers, one above the other, and connecting them with a thin tube (2).
これらの容器のうち上段の容器Ｑａ）は、当初その中に
溶融金属（３）を入れて該溶融金属（３）を加圧する加
圧容器として用いる。この時下段の容器（１ｂ）は、そ
の中に溶融金属（３）に可溶なガスを満たし、そこから
細管（２）を介して上段容器（１ａ）内の溶融金属（３
）中に該ガスをバブリングするガス吹き込み容器として
用いる。Among these containers, the upper container Qa) is used as a pressurizing container in which molten metal (3) is initially placed and the molten metal (3) is pressurized. At this time, the lower container (1b) is filled with gas that is soluble in the molten metal (3), and from there the molten metal (3) in the upper container (1a) is passed through the thin tube (2).
) is used as a gas blowing container for bubbling the gas into the container.
その後、下段容器（１ｂ）からバブリングガスを抜いて
上段容器（１ａ）へのバブリングを停止すると、溶融金
属（３）は細管（２）を介して下段容器（１ｂ）内へ重
力により移動する。この時下段容器（１ｂ）は、その中
を更に減圧して減圧容器として用いる口
以上の装置構成で上述め清浄化方法を実施する場合、両
容器（１ａＸｉｂ）をつないでいる細管（２）を細（、
且つ下段容器（１ｂ）内のガス吹き込み圧を十分に高く
しておけば、前記上段容器（１ａ）を加圧容器として使
用している時に、該上段容器（１ａ）内の溶融金属（２
）は、下段容器（１ｂ）内へ漏出してし才うことがない
。従って上段容器（１ａ）内では、バブリングによる溶
融金属（３）中の通常介在物の浮上と、ガスの溶は込み
が十分に行なわれる。一方下段容器（１ｂ）のガス抜き
を行なって上段容器（１ａ）へのバブリングを停止した
時に、はじめて溶融金属（３）は細管（２）を通って下
段容器（１ｂ）に移動することになる。その後に下段容
器（１ｂ）内の減圧を行なって微細ガス気泡を発生せし
めることにより、溶融金属（３）中の微細介在物が浮上
せしめられることになる。Thereafter, when the bubbling gas is removed from the lower container (1b) and bubbling to the upper container (1a) is stopped, the molten metal (3) moves by gravity into the lower container (1b) via the thin tube (2). At this time, when the lower container (1b) is further depressurized and the above-mentioned cleaning method is carried out with a device configuration having more than one opening for use as a decompression container, the thin tube (2) connecting both containers (1aXib) is used. Thin (,
In addition, if the gas blowing pressure in the lower container (1b) is sufficiently high, when the upper container (1a) is used as a pressurized container, the molten metal (2
) will not leak into the lower container (1b). Therefore, in the upper container (1a), normal inclusions in the molten metal (3) are brought to the surface by bubbling, and gas is sufficiently melted and included. On the other hand, only when the lower container (1b) is degassed and bubbling to the upper container (1a) is stopped, does the molten metal (3) move through the thin tube (2) to the lower container (1b). . Thereafter, the pressure inside the lower container (1b) is reduced to generate fine gas bubbles, thereby causing fine inclusions in the molten metal (3) to float.
以下本発明の具体的実施例につき説明する。 Specific examples of the present invention will be described below.
第２図は溶鋼の清浄化処理を行なう本発明の実施例装量
の装置構成を示している。FIG. 2 shows the configuration of a charging device according to an embodiment of the present invention for cleaning molten steel.
当該装置は、内径２ｍ、高さ３ｍの鋼製タンクからなる
密閉容器（１ｏａＸ１ｏｂ）二つを上下に重ね合わせて
、その間を径２０１１ｃｍの細管翰２５本（図では１本
のみ表示）で連通せしめた構成からなり、両容器（ｘｏ
ａＸｌｏｂ）はフレーム（４０）で支持されている。又
上段の容器（ＸＯａ）の上面には、該容器（ＸＯａ）内
へＡｒガスの吹き込みを行なう供給管Ｉ、そこから該ガ
スの排出を行なう排出管（１７Ｊ及び該容器（１０ａ）
内への未処理溶鋼−を供給する注湯管（２）が接続され
ている。他方、下段容器（１ｏｂ）の側面上方には、そ
の中にＡｒガス： ７０％、塩ガス：３０チからなる混
合ガスを吹き込む吹込み管Ｉ及びその中のガスを抜き出
し、必要に応じて更にその中の減圧を行なう抜出し管四
が接続されている。The device consists of two closed containers (1 oa x 1 ob) made of steel tanks with an inner diameter of 2 m and a height of 3 m, stacked one on top of the other, and communicated between them through 25 thin tubes (only one is shown in the figure) with a diameter of 2011 cm. Both containers (xo
aXlob) is supported by a frame (40). Further, on the upper surface of the upper container (XOa), there is a supply pipe I for blowing Ar gas into the container (XOa), a discharge pipe (17J and the container (10a) for discharging the gas from there).
A pouring pipe (2) for supplying untreated molten steel to the inside is connected. On the other hand, above the side of the lower container (1ob), there is a blowing pipe I into which a mixed gas consisting of 70% Ar gas and 30% salt gas is blown, and the gas therein is extracted, and if necessary, further An extraction pipe 4 for reducing the pressure therein is connected.
この装置では、吹込み管Ｉ及び抜出し管（Ｌｌによって
下段容器（１０ｂ）内のカスパージが行なわれた後、該
下段容器（ｊｏｂ）内が前記混合ガスで５気圧程度にな
るように調整する。この時、上段容器（１０ａ）でも、
供給管←Ｄ及び排出管住ｚによって内部がカスパージさ
れてＡｒガスで満たされるようにする。それと共に、注
湯管ｕ３から溶鋼（至）を上段容器Ｑｏａ）内に供給す
る。その供給量としては径２ｍＸ高さ２ｍ重量５０ｔｏ
ｎ程度とすると良い。そして上段容器（１０ａ）内のガ
ス雰囲気を３気圧程度とすると、下段容器（１０ｂ）側
から細管■を通って溶鋼（至）中へ前記混合カスがバブ
リングされることになる。この時、両容器（１０ａ）（
１０ｂ）内の圧力差と溶鋼翰量細管（４）の径とのバラ
ンスがちょうどとれることで、溶鋼（７）が下段容器（
１０ｂ）内へ漏出してしまうことがなく、該溶鋼（７）
は上段容器（１ｏａ）内で十分に加圧されつつ、混合カ
スによるバブリングが行なわれることになる。In this device, after the inside of the lower container (10b) is casparged by the blow-in pipe I and the extraction pipe (Ll), the inside of the lower container (job) is adjusted to about 5 atmospheres with the mixed gas. At this time, even in the upper container (10a),
The inside is casparged by the supply pipe←D and the discharge pipe Z so that it is filled with Ar gas. At the same time, molten steel is supplied from the pouring pipe u3 into the upper container Qoa). The supply amount is 2m in diameter x 2m in height and 50to in weight.
It is good to set it to about n. When the gas atmosphere in the upper container (10a) is about 3 atmospheres, the mixed scum is bubbled from the lower container (10b) side through the thin tube (2) into the molten steel. At this time, both containers (10a) (
10b) and the diameter of the molten steel receiving tube (4), the molten steel (7) flows into the lower container (
10b) without leaking into the molten steel (7).
is sufficiently pressurized in the upper container (1 oa), and bubbling is performed by the mixed dregs.
その後、吹込み管Ｉからの混合カスの吹き込みを止め、
抜出し管四により下段容器（１０ｂ）内のガス抜きを行
なう。すると上段容器（１０ａ）から細管四を通って該
下段容器（１０ｂ）に溶鋼（至）が流れることになる。After that, stop blowing the mixed waste from the blowing pipe I,
The gas inside the lower container (10b) is vented through the extraction pipe 4. Then, the molten steel flows from the upper container (10a) to the lower container (10b) through the thin tube 4.
そして前記供給管圓によるＡｒガスの供給を行なうと共
に、抜き出し管四によって下段容器（ｘｏｂ）内のガス
抜きを更に続け、容器（ｉｏｂ）内界囲気を大気圧程度
に減圧する。この減圧によって溶鋼（７）中から微細ガ
ス気泡（主にＨ２ガス）が発生し、しばらく放置する。Then, while supplying Ar gas through the supply pipe 4, the gas inside the lower container (xob) is further continued to be vented through the extraction pipe 4, and the pressure inside the container (iob) is reduced to approximately atmospheric pressure. Due to this pressure reduction, fine gas bubbles (mainly H2 gas) are generated from the molten steel (7), and the molten steel (7) is left for a while.
その後、容器を傾斜させ溶鋼（至）を取出口（図中省略
）より取り出す。Thereafter, the container is tilted and the molten steel is taken out from the outlet (not shown).
以上の処理で当初該溶鋼国中のトータル酸素量は８０
ｐｐｍ程度であったものが、１５ｐｐｍ Ｑ度に低減さ
れることになった。With the above treatment, the total amount of oxygen in the molten steel was initially 80
What used to be about ppm was reduced to 15 ppm Q degree.
以上詳述した本発明の清浄化装量によれば、上述した清
浄化方法の実施にあたり、ストッパ等の消耗品を使用す
ることがなく、且つ二つの容器が連通した状態でも該清
浄化方法が効率良〈実施できるため、装置のメンテナン
スに手間・暇がかからず、しかも当該方法の実施中に溶
融金属の容器間の移動が不可能となるような事故は起こ
らないことになる。According to the cleaning charge of the present invention described in detail above, when implementing the cleaning method described above, there is no need to use consumables such as a stopper, and the cleaning method is efficient even when two containers are in communication. Since this method can be carried out successfully, maintenance of the equipment does not require much effort or time, and moreover, accidents such as the inability to move molten metal between containers will not occur during implementation of the method.
第１図は本発明の装置構成を示す説明図、第２図は本発
明の一実施例に係る装置構成を示す正断面図、第３図は
溶融金属の清浄化方法の実施に当初用いられた装量構成
を示す説明図である。
図中（１ａＸ１ｂ）（１０ａＸ１０ｂＸ１００Ｘ１０１
）は容器、（２１彌は細管、（３）は溶融金属、（至）
は溶鋼、（２００）はストッパを各示す。
特許出願人 日本鋼管株式会社
発 明 者 石 井 俊 夫同
大久保 豊
同 福 １） 僑 三代
理人弁理士 吉 原 省 三同 同
苫米地 正 敏
手続補正書（自発）
昭和６３年１０月２８日FIG. 1 is an explanatory diagram showing the configuration of an apparatus according to the present invention, FIG. 2 is a front sectional view showing the configuration of an apparatus according to an embodiment of the present invention, and FIG. 3 is an explanatory diagram showing the configuration of an apparatus according to an embodiment of the present invention. FIG. In the diagram (1aX1b) (10aX10bX100X101
) is a container, (21 is a thin tube, (3) is a molten metal, (to)
(200) indicates the molten steel, and (200) indicates the stopper. Patent applicant: Nippon Kokan Co., Ltd. Inventor: Toshio Ishii
Fuku Okubo Toyodo 1) Overseas Patent Attorney Sho Yoshihara Sando
Tomabechi Masatoshi Procedural Amendment (Voluntary) October 28, 1986
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP685488A JPH01181953A (en) | 1988-01-18 | 1988-01-18 | Apparatus for cleaning molten metal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP685488A JPH01181953A (en) | 1988-01-18 | 1988-01-18 | Apparatus for cleaning molten metal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01181953A true JPH01181953A (en) | 1989-07-19 |
Family
ID=11649819
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP685488A Pending JPH01181953A (en) | 1988-01-18 | 1988-01-18 | Apparatus for cleaning molten metal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01181953A (en) |
-
1988
- 1988-01-18 JP JP685488A patent/JPH01181953A/en active Pending
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