JPH0320404A - Method for protecting iron shell at bottom part in vacuum degassing apparatus - Google Patents
Method for protecting iron shell at bottom part in vacuum degassing apparatusInfo
- Publication number
- JPH0320404A JPH0320404A JP15634289A JP15634289A JPH0320404A JP H0320404 A JPH0320404 A JP H0320404A JP 15634289 A JP15634289 A JP 15634289A JP 15634289 A JP15634289 A JP 15634289A JP H0320404 A JPH0320404 A JP H0320404A
- Authority
- JP
- Japan
- Prior art keywords
- slag layer
- vacuum degassing
- slag
- bottom part
- iron shell
- 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
- 238000009849 vacuum degassing Methods 0.000 title claims abstract description 24
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 20
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 10
- 238000000034 method Methods 0.000 title claims description 9
- 239000002893 slag Substances 0.000 claims abstract description 37
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 15
- 239000010959 steel Substances 0.000 claims abstract description 15
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 abstract description 8
- 235000019738 Limestone Nutrition 0.000 abstract description 5
- 239000006028 limestone Substances 0.000 abstract description 5
- 235000010216 calcium carbonate Nutrition 0.000 abstract description 4
- 229910000019 calcium carbonate Inorganic materials 0.000 abstract description 4
- 238000001816 cooling Methods 0.000 abstract description 3
- 238000000354 decomposition reaction Methods 0.000 abstract description 3
- 239000000203 mixture Substances 0.000 abstract description 3
- 238000006243 chemical reaction Methods 0.000 abstract description 2
- 238000003756 stirring Methods 0.000 abstract description 2
- 230000005855 radiation Effects 0.000 abstract 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 14
- 239000000395 magnesium oxide Substances 0.000 description 7
- 238000007872 degassing Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000007670 refining Methods 0.000 description 3
- 239000011449 brick Substances 0.000 description 2
- 239000010459 dolomite Substances 0.000 description 2
- 229910000514 dolomite Inorganic materials 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 241000473391 Archosargus rhomboidalis Species 0.000 description 1
- 230000001174 ascending effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Treatment Of Steel In Its Molten State (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、溶鋼の真空脱ガス処理において、真空脱ガス
装置の底部鉄皮の熱負荷を軽減することによりその赤熱
変形を防止する、真空脱ガス装置の底部鉄皮の保護方法
に関するものである．（従来の技術）
溶鋼の２次精錬として、溶鋼の真空脱ガス処理が広く実
施されていることは周知の通りである。Detailed Description of the Invention (Industrial Application Field) The present invention provides a vacuum degassing process for molten steel that prevents red-hot deformation by reducing the heat load on the bottom shell of a vacuum degassing device. This article concerns a method for protecting the bottom shell of a degassing device. (Prior Art) It is well known that vacuum degassing treatment of molten steel is widely practiced as secondary refining of molten steel.
第１図は、ＲＨ式真空脱ガス装置による処理状況を示し
たもので、１は取鍋、２は溶鋼、３は表面スラグ層、４
はＲＨ式真空脱ガス装置、５．６は上昇管及び下降管で
ある．
近年、鯛の高清浄化の要請から、取鍋内の溶鋼又は脱ガ
ス槽内の溶鋼にフラックス（例えば、ＣａＯ−ＣａＦｇ
）を添加するようになってきた（特公昭６２一３９２０
５号公報、同５Ｂ−１７２４８号公報参照）。ｆ？１ｔ
ａに添加されたＣａＦオが浮上してスラグ層に到達する
と、スラグ層の融点を下げスラグ層は溶融状態になる．
スラグ層が溶融状態になるとスラグ層からの輻射熱が増
大し、ＲＨ式真空脱ガス装置の底部鉄皮７が熱変形し、
脱ガス槽内の煉瓦が損傷するという問題があった。Figure 1 shows the processing situation using the RH vacuum degassing device, where 1 is a ladle, 2 is molten steel, 3 is a surface slag layer, and 4 is a ladle.
is an RH type vacuum degassing device, and 5.6 is an ascending pipe and a downcomer pipe. In recent years, due to the demand for high purity of sea bream, flux (e.g. CaO-CaFg) is added to the molten steel in the ladle or in the degassing tank.
) began to be added (Special Publication No. 62-3920
(See Publications No. 5 and No. 5B-17248). f? 1t
When the CaF added to a floats up and reaches the slag layer, it lowers the melting point of the slag layer and the slag layer becomes molten.
When the slag layer becomes molten, the radiant heat from the slag layer increases, and the bottom iron skin 7 of the RH vacuum degasser is thermally deformed.
There was a problem that the bricks in the degassing tank were damaged.
従来から、この種の問題解決のために、底部鉄皮７に防
熱手段等を施こして直接の熱負荷を軽減することが試み
られている（例えば、実開昭５４−１４３８２３号公報
，実開昭５７−３５３６１号公報，実開昭６２−９３３
５６号公報）。Conventionally, in order to solve this kind of problem, attempts have been made to reduce the direct heat load by providing heat insulation means etc. to the bottom iron skin 7 (for example, Japanese Utility Model Application Publication No. 143823/1983, Publication No. 57-35361, Utility Model Publication No. 62-933
Publication No. 56).
（発明が解決しようとする課題）
ところが、近年のフラックス処理の増大により、上記の
対策では限界があり底部鉄皮７の保護としては不十分な
ものであった。(Problems to be Solved by the Invention) However, due to the increase in flux treatment in recent years, the above-mentioned measures have limitations and are insufficient to protect the bottom iron skin 7.
本発明は上記の点に鑑み、効果的に底部鉄皮の熱変形を
防止する底部鉄皮の保護方法を提供するものである。In view of the above points, the present invention provides a method for protecting a bottom steel shell that effectively prevents thermal deformation of the bottom steel shell.
（課題を解決するための手段） 本発明の要旨は、次のとおりである。(Means for solving problems) The gist of the present invention is as follows.
表面に溶融スラグ層が存在する取鍋内の溶鋼を真空脱ガ
ス処理するにさいし、真空脱ガス処理の前又は真空脱ガ
ス処理中に、上記溶融スラグ層にＣａＣＯｉ とＭｇＯ
を併用添加して溶融スラグ層を冷却固化し、スラグ層か
らの輻射熱の減少を図ることを特徴とする真空脱ガス装
置の底部鉄皮の保護方法。When performing vacuum degassing treatment on molten steel in a ladle that has a molten slag layer on its surface, CaCOi and MgO are added to the molten slag layer before or during the vacuum degassing treatment.
1. A method for protecting a bottom iron skin of a vacuum degassing device, characterized in that the molten slag layer is cooled and solidified by adding a combination of slag and slag to reduce radiant heat from the slag layer.
以下、本発明の内容を詳細に説明する．本発明における
ＣａＣＯｓとＭｇＯの取鍋内スラグ層への添加は、真空
脱ガス処理前、真空脱ガス処理開始直後、若しくはその
双方の時点において行うものである．
取鍋内スラグ層へ添加されたＣａＣＯ３は（１）石灰石
の分解吸熱反応であるＣａＣＯｓ−ＣａＯ＋ＣＯｚ ↑
及び（２）石灰石の分解時のＣＯ！ガスによる攪拌によ
り取鍋内スラグ層に冷却作用を与え、一方、同時に添加
したＭｇＯはスラグ組威を変化してスラグの融点を上昇
させる作用を有するものである。これらの作用によって
スラグ層は冷却固化され、スラグ層からの輻射熱が大幅
に減少する結果、真空脱ガス装直の底部鉄皮の赤熱変形
が防止できるものである。The contents of the present invention will be explained in detail below. In the present invention, CaCOs and MgO are added to the slag layer in the ladle before the vacuum degassing treatment, immediately after the start of the vacuum degassing treatment, or at both times. CaCO3 added to the slag layer in the ladle is (1) CaCOs-CaO+COz, which is an endothermic reaction of decomposition of limestone.
and (2) CO during decomposition of limestone! The stirring by the gas gives a cooling effect to the slag layer in the ladle, while the MgO added at the same time has the effect of changing the slag composition and raising the melting point of the slag. As a result of these actions, the slag layer is cooled and solidified, and radiant heat from the slag layer is significantly reduced, red-hot deformation of the bottom shell of the vacuum degassing system can be prevented.
ＣａＣＯｓとＭｇＯの使用割合は、ＣａＣＯｓ：ＭｇＯ
＝ ２ ： ８〜８：２が好ましく、又両者の添加量は
、０． ５〜３． ０ ｋｇ／ ｔ−ｓｔｅｅｌが好ま
しい。The usage ratio of CaCOs and MgO is CaCOs:MgO
= 2:8 to 8:2 is preferable, and the amount of both added is 0. 5-3. 0 kg/t-steel is preferred.
なお、ＭｇＯ源としては転炉の廃煉瓦、マグネシアクリ
ンカーあるいは生ドロマイトを使用することができ、Ｃ
ａＣＯ．源としては石灰石、生ドロマイトを使用するこ
とができる。As the MgO source, waste bricks from converters, magnesia clinker, or raw dolomite can be used.
aCO. As a source, limestone, raw dolomite can be used.
（実施例）
転炉出鋼時にフラックスとしてＣａＯ−ＣａＦ．を添加
した第１表の組成のスラグを有する第２表の溶鋼を１
０ ０ ｔｏｎ／ｃｈｏＲＨ式真空脱ガス処理により２
次精錬を実施し、第３表の溶鋼を得た．その際、第４表
に示す如く真空脱ガス処理前に本発明の方法を実施した
．実施結果を第５表に示す。(Example) CaO-CaF. The molten steel shown in Table 2 having the slag having the composition shown in Table 1 with the addition of
0 0 ton/cho 2 by RH vacuum degassing treatment
The next refining was carried out to obtain the molten steel shown in Table 3. At that time, as shown in Table 4, the method of the present invention was carried out before vacuum degassing treatment. The implementation results are shown in Table 5.
（発明の効果）
以上詳述した如く、本発明の方法によれば真空脱ガス処
理中の取鍋内スラグ層からの輻射熱を減じることにより
底部鉄皮の熱保護が図れて底部鉄皮赤熱変形トラブルが
大幅に減少するものであり、溶鋼の真空脱ガス処理によ
る２次精錬に大きく寄与したものである。(Effects of the Invention) As detailed above, according to the method of the present invention, thermal protection of the bottom shell is achieved by reducing radiant heat from the slag layer in the ladle during vacuum degassing treatment, resulting in red-hot deformation of the bottom shell. This greatly reduces troubles and greatly contributes to secondary refining by vacuum degassing treatment of molten steel.
第１図はＲＨ式真空脱ガス処理の説明図である。
ｌ・・・取鍋、２・・・溶鋼、３・・・スラグ層、４・
・・ＲＨ式真空脱ガス装置、７・・・底部鉄皮FIG. 1 is an explanatory diagram of the RH vacuum degassing process. l... Ladle, 2... Molten steel, 3... Slag layer, 4...
...RH type vacuum degassing device, 7...Bottom iron skin
Claims (1)
ス処理するにさいし、真空脱ガス処理の前又は真空脱ガ
ス処理中に、上記溶融スラグ層にＣａＣＯ＿３とＭｇＯ
を併用添加して溶融スラグ層を冷却固化し、スラグ層か
らの輻射熱の減少を図ることを特徴とする真空脱ガス装
置の底部鉄皮の保護方法。When performing vacuum degassing treatment on molten steel in a ladle that has a molten slag layer on its surface, CaCO_3 and MgO are added to the molten slag layer before or during the vacuum degassing treatment.
1. A method for protecting a bottom iron skin of a vacuum degassing device, characterized in that the molten slag layer is cooled and solidified by adding a combination of slag and slag to reduce radiant heat from the slag layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15634289A JPH0320404A (en) | 1989-06-19 | 1989-06-19 | Method for protecting iron shell at bottom part in vacuum degassing apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15634289A JPH0320404A (en) | 1989-06-19 | 1989-06-19 | Method for protecting iron shell at bottom part in vacuum degassing apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0320404A true JPH0320404A (en) | 1991-01-29 |
Family
ID=15625674
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15634289A Pending JPH0320404A (en) | 1989-06-19 | 1989-06-19 | Method for protecting iron shell at bottom part in vacuum degassing apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0320404A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007503315A (en) * | 2003-08-27 | 2007-02-22 | プロライト ヴァストゴード ビー．ヴイ． | Welding device and welding torch |
-
1989
- 1989-06-19 JP JP15634289A patent/JPH0320404A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007503315A (en) * | 2003-08-27 | 2007-02-22 | プロライト ヴァストゴード ビー．ヴイ． | Welding device and welding torch |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4417924A (en) | Steelmaking additive composition | |
| US3258328A (en) | Method and apparatus for treating steel | |
| JP3040343B2 (en) | Method for treating aluminum slag and aluminum slag residue to calcium aluminate | |
| JP3557910B2 (en) | Hot metal dephosphorization method and low sulfur and low phosphorus steel smelting method | |
| CN108384921A (en) | A kind of ladle refining lime stone core-spun yarn and its application method | |
| US4490173A (en) | Steelmaking additive composition | |
| JP3428628B2 (en) | Stainless steel desulfurization refining method | |
| JPH0320404A (en) | Method for protecting iron shell at bottom part in vacuum degassing apparatus | |
| US3893846A (en) | Slag forming agent for steel making | |
| CA1102555A (en) | Process and agent for the desulphurization of iron based melts | |
| JPS587691B2 (en) | Steel manufacturing method | |
| US1925247A (en) | Purifying ferrous metals | |
| US3579325A (en) | Steel-making process employing an auxiliary composition | |
| US3666445A (en) | Auxiliary composition for steel-making furnaces | |
| JPS6123243B2 (en) | ||
| JP3598843B2 (en) | Method for reducing unslagged CaO and MgO in slag | |
| SU1313879A1 (en) | Method for melting steel | |
| JPH08134526A (en) | Magnesia-base slag formation promoter for refining limy flux and its production | |
| US2816018A (en) | Process for the production of steel from high phosphorus pig iron | |
| JPS6225724B2 (en) | ||
| JPS6154081B2 (en) | ||
| JP3728870B2 (en) | Desulfurization method and desulfurization agent for iron-based molten alloy | |
| KR100926321B1 (en) | Metallurgical treatment method on a metal bath | |
| JPH10317035A (en) | Desulphurization method of ferrous molten alloy, and desulphurizing agent | |
| KR20240045560A (en) | Converter process using waste acid sludge |