JPS629315Y2 - - Google Patents
Info
- Publication number
- JPS629315Y2 JPS629315Y2 JP2513283U JP2513283U JPS629315Y2 JP S629315 Y2 JPS629315 Y2 JP S629315Y2 JP 2513283 U JP2513283 U JP 2513283U JP 2513283 U JP2513283 U JP 2513283U JP S629315 Y2 JPS629315 Y2 JP S629315Y2
- Authority
- JP
- Japan
- Prior art keywords
- nozzle
- blowing nozzle
- gas
- bottom blowing
- cap
- 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
Links
- 238000007664 blowing Methods 0.000 claims description 50
- 239000007789 gas Substances 0.000 description 31
- 239000011449 brick Substances 0.000 description 19
- 230000008439 repair process Effects 0.000 description 16
- 239000011823 monolithic refractory Substances 0.000 description 13
- 239000002184 metal Substances 0.000 description 10
- 229910000831 Steel Inorganic materials 0.000 description 9
- 239000010959 steel Substances 0.000 description 9
- 239000007921 spray Substances 0.000 description 6
- 238000005507 spraying Methods 0.000 description 6
- 238000003756 stirring Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 239000002893 slag Substances 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
Description
【考案の詳細な説明】
本考案は転炉の底吹ノズルに関するものであ
る。[Detailed Description of the Invention] The present invention relates to a bottom blowing nozzle for a converter.
周知の如く近年の転炉においては底吹吹錬ある
いは上底吹吹錬が積極的に実施されるようになつ
ている。これに伴い底吹ノズルの開発およびその
寿命を延長させるための研究も種々行われてお
り、多くの提案がなされている。 As is well known, in recent years, bottom blowing or top bottom blowing has been actively carried out in converters. Along with this, various studies have been conducted to develop bottom-blown nozzles and extend their lifespan, and many proposals have been made.
ところで底吹ノズルは通常第１図に示すように
炉底煉瓦壁に装着して用いられている。 By the way, the bottom blowing nozzle is usually used by being attached to the brick wall of the bottom of the furnace, as shown in FIG.
即ち、第１図において１は転炉、２は上吹ラン
ス、３は溶鋼、４は炉内煉瓦壁を示し、底吹ノズ
ル５は溶鋼３の浴面下に位置する炉底煉瓦壁４０
に装着されている。 That is, in FIG. 1, 1 is a converter, 2 is a top blowing lance, 3 is molten steel, 4 is a brick wall in the furnace, and a bottom blowing nozzle 5 is a bottom brick wall 40 located below the bath surface of molten steel 3.
is installed on.
第２図は前記底吹ノズル５の装着状況の一実施
例を示す部分断面構造図である。 FIG. 2 is a partial cross-sectional structural view showing an example of how the bottom blowing nozzle 5 is installed.
本実施例において、底吹ノズル５は炉底煉瓦壁
４０に埋設された羽口煉瓦４１に装着され、羽口
押え煉瓦４２，４３によつて固定されている。 In this embodiment, the bottom blowing nozzle 5 is attached to a tuyere brick 41 buried in a hearth brick wall 40 and fixed by tuyere holding bricks 42 and 43.
さて本出願人は、上吹ランス２よりO2を底吹
ノズル５より撹拌ガスを底吹きする上底吹吹錬に
おいて、ノズル寿命延長を計ると共に極めて少量
から大量のガス吹込みを効率的に実施可能ならし
める底吹ノズルとして、前記第２図に示すように
小径の金属管６を複数個埋設して構成したものを
発明し先に出願した。 Now, in top-bottom blowing, in which O 2 is bottom-blown from the top-blowing lance 2 and stirring gas is bottom-blown from the bottom-blowing nozzle 5, the applicant aims to extend the life of the nozzle and efficiently blow gas from an extremely small amount to a large amount. As a practical bottom-blowing nozzle, we have invented and previously applied for a nozzle constructed by burying a plurality of small-diameter metal tubes 6, as shown in FIG.
而して、該底吹ノズル５ではガス供給管７より
供給される撹拌ガスがヘツダー部８を介して前記
金属管６より炉内へ吹込まれる。ところが前記底
吹ノズル５においても使用期間の経過に伴つて順
次損耗する。該底吹ノズル５の損耗は、その周辺
の炉底煉瓦壁４０の損耗速度より大きく、炉内煉
瓦壁４の一回の補修期間（１サイクル）の間に10
〜13回の底吹ノズル５の取替が必要となる。 In the bottom blowing nozzle 5, the stirring gas supplied from the gas supply pipe 7 is blown into the furnace from the metal pipe 6 via the header part 8. However, the bottom blowing nozzle 5 also gradually wears out as the period of use passes. The wear rate of the bottom blowing nozzle 5 is greater than the wear rate of the surrounding furnace bottom brick wall 40, and the wear rate of the bottom blowing nozzle 5 is greater than the wear rate of the furnace bottom brick wall 40.
It is necessary to replace the bottom blow nozzle 5 ~13 times.
第２図において破線ｘは前述の底吹ノズル５の
取替時の損耗状況を示すもので、底吹ノズル５を
中心としてその周辺部の羽口煉瓦４１や炉底煉瓦
４０ａも損耗することが一般的である。 In FIG. 2, the broken line x indicates the state of wear and tear when the bottom blowing nozzle 5 is replaced, and the tuyere bricks 41 and hearth bricks 40a around the bottom blowing nozzle 5 may also be worn out. Common.
このため、損耗した底吹ノズル５の取替えに際
して前記損耗した羽口煉瓦４１や炉底煉瓦４０ａ
の部分的補修を実施する手段も種々提案されてい
る。 Therefore, when replacing the worn out bottom blowing nozzle 5, the worn out tuyere bricks 41 and the hearth bottom bricks 40a are replaced.
Various methods have also been proposed for carrying out partial repairs.
例えば第３図に示すように新規の底吹ノズル５
を装着した後、前記損耗部９に溶融スラグを流し
込み固化せしめたり、あるいは不定形耐火物を充
填、又は吹付して補修する手段が提案され実施さ
れている。ところが、該補修においては底吹ノズ
ル５のガス吹出口、つまり金属管６にスラグや不
定形耐火物が進入して孔詰まりを生ずる事態が
屡々あつた。該孔詰まりを防止するために例えば
底吹ノズル５より所定圧のガスを吹出しながら前
記補修を実施する手段やノズル上面に盲蓋を置い
て実施する手段等が試みられている。しかしなが
ら前者においては、確実な進入防止は行い難く、
特に不定形耐火物を吹付補修する場合等にはガス
圧を高くしても粒状の不定形耐火物の進入を防止
することはできなかつた。 For example, as shown in Fig. 3, a new bottom-blowing nozzle 5
After installation, methods have been proposed and implemented in which repair is performed by pouring molten slag into the worn portion 9 and solidifying it, or by filling or spraying monolithic refractories. However, during this repair, slag and monolithic refractories often entered the gas outlet of the bottom blow nozzle 5, that is, the metal tube 6, causing hole clogging. In order to prevent the hole clogging, attempts have been made to carry out the repair while blowing gas at a predetermined pressure from the bottom blow nozzle 5, or by placing a blind cover on the top of the nozzle. However, in the former case, it is difficult to reliably prevent intrusion;
In particular, when spraying and repairing monolithic refractories, even if the gas pressure is increased, it has not been possible to prevent the intrusion of granular monolithic refractories.
一方、後者においては、新規の底吹ノズル５を
装着した後にガス吹出し試験（底吹ノズル５より
撹拌ガスが正常に吹出すか、あるいはその際にガ
ス供給管７の接合部等よりガス漏洩がないか等の
試験）を実施する必要があり、盲蓋を載置した状
態では前記試験ができない。 On the other hand, in the latter case, after installing the new bottom blowing nozzle 5, a gas blowing test is carried out (whether the stirring gas blows out normally from the bottom blowing nozzle 5, or whether there is no gas leakage from the joint of the gas supply pipe 7, etc.). It is necessary to carry out a test such as 1), and the above test cannot be performed with the blind lid in place.
又、前記試験を実施した後、盲蓋を載置するこ
とは炉内が極めて高温であり、かつ炉口よりの距
離が９〜10ｍと遠く離れていることから実質上不
可能である。 Furthermore, it is virtually impossible to place a blind lid after carrying out the above test because the temperature inside the furnace is extremely high and the distance from the furnace mouth is as far as 9 to 10 meters.
本考案は前記問題点の抜本的解決を計るために
創案されたものであつて、前述した底吹ノズルの
取替後の部分補修を容易に、かつ確実に実施可能
ならしめる底吹ノズルの提供をその主たる目的と
するものである。 The present invention was devised to fundamentally solve the above-mentioned problems, and provides a bottom-blowing nozzle that allows for easy and reliable partial repair after replacement of the bottom-blowing nozzle. is its main purpose.
以下実施例に基づき本考案を詳述する。 The present invention will be described in detail below based on Examples.
第４図は本考案に基づく底吹ノズルの一実施例
を示す斜視図である。 FIG. 4 is a perspective view showing an embodiment of the bottom blowing nozzle based on the present invention.
本考案の底吹ノズル５０は、ノズル本体５１の
頭部に筒状のキヤツプ５２を固着して構成されて
いる。本実施例のキヤツプ５２は、ノズル本体５
１の頭部５１ａに所定量嵌合するように形成され
ており、前記頭部５１ａに嵌合せしめた後、例え
ば周知の止めビスあるいは金属円錐形ネジ等の止
具５３によつて固着されている。 The bottom blowing nozzle 50 of the present invention is constructed by fixing a cylindrical cap 52 to the head of a nozzle body 51. The cap 52 of this embodiment is the nozzle body 5.
1, and after being fitted into the head 51a, it is fixed with a stopper 53 such as a well-known set screw or a metal conical screw. There is.
キヤツプ５２の頂部側面には気抜孔５４が形成
されている。又、キヤツプ５２は後述する補修が
終了し溶鋼３が注入されたときに直ちに溶融する
よう例えば鋼板、非鉄鋼板、プラスチツク板等の
如き易溶性のもので構成されている。 A vent hole 54 is formed in the top side of the cap 52. Further, the cap 52 is made of an easily meltable material such as a steel plate, a non-ferrous steel plate, a plastic plate, etc. so that it melts immediately when the molten steel 3 is injected after the repair described later is completed.
第５図は前記底吹ノズル５０を装着した後、損
耗部９に不定形耐火物を吹付補修する状況を示す
もので、転炉１を横傾せしめた後、吹付ノズル１
０より不定形耐火物を前記損耗部９およびその周
辺の煉瓦壁に吹付け耐火層１１を形成せしめる。
該吹付補修を開始する前にガス供給管７より底吹
ノズル５０にN2，Ar，CO2等のガスを供給する
と該ガスはキヤツプ５２に形成された気抜孔５４
より炉内に噴出し、このときの配管途中における
ガス漏洩や底吹ノズル５０よりガスが正常に噴出
しているか否かの確認が例えばガス供給圧力の変
動等をチエツクすることによつて可能である。 FIG. 5 shows a situation in which the worn part 9 is sprayed with monolithic refractory after the bottom blowing nozzle 50 is installed, and after the converter 1 is tilted sideways, the spray nozzle 1 is
A sprayed refractory layer 11 is formed by spraying an amorphous refractory from No. 0 on the worn portion 9 and the brick wall around it.
Before starting the spray repair, when a gas such as N 2 , Ar, or CO 2 is supplied from the gas supply pipe 7 to the bottom blow nozzle 50 , the gas flows through the air vent hole 54 formed in the cap 52 .
At this time, it is possible to check whether gas is leaking in the middle of the piping or whether the gas is being ejected normally from the bottom blowing nozzle 50 by checking, for example, fluctuations in the gas supply pressure. be.
又、前記吹付補修の間において前述のガスを連
続的に噴出せしめると不定形耐火物が気抜孔５４
より進入することが全くなく、キヤツプ５２の遮
へい効果に加えて噴出するガス圧で金属管６に不
定形耐火物が進入し、詰まりを生ずることが確実
に防止できる。 Moreover, if the above-mentioned gas is continuously blown out during the spray repair, the monolithic refractory material will leak through the air vent holes 54.
In addition to the shielding effect of the cap 52, the ejected gas pressure can reliably prevent the monolithic refractory from entering the metal tube 6 and causing clogging.
即ち、本考案の底吹ノズル５０では前述の如く
ノズル本体５１の上方を頂部側面のみに気抜孔５
４を有する被帽体状に形成されたキヤツプ５２で
覆設して構成されていることから、底吹ノズル５
０の頂面に対しほゞ直角に近い炉口１ａ方向から
吹付けられる不定形耐火物をノズル本体５１の頭
面５１ｂに開口した金属管６から確実に遮へいで
きるうえにノズル本体頭面５１ｂとキヤツプ５２
内面に形成される空間５２ａがヘツダー機能を発
揮し、キヤツプ５２の頂部側面に形成された気抜
孔５４より噴出するガスは気抜孔５４の全体より
均等な圧力で噴出し、このため前記吹付補修中に
おける不定形耐火物の進入を確実に防止できるこ
とが本考案者等の経験で確認された。 That is, in the bottom blowing nozzle 50 of the present invention, as described above, the air vent hole 5 is provided only on the top side surface above the nozzle body 51.
4, the bottom blowing nozzle 5
In addition to being able to reliably shield the monolithic refractories sprayed from the direction of the furnace opening 1a, which is nearly perpendicular to the top surface of the nozzle body 51, from the metal tube 6 opened in the head surface 51b of the nozzle body 51, the nozzle body head surface 51b cap 52
The space 52a formed on the inner surface functions as a header, and the gas ejected from the air vent hole 54 formed on the side surface of the top of the cap 52 is ejected at a uniform pressure from the entire air vent hole 54, so that the gas is ejected at an even pressure during the above-mentioned spray repair. The experience of the present inventors has confirmed that the intrusion of monolithic refractories can be reliably prevented.
次に本考案の具体的な実施例について説明す
る。第６図に断面構造図で示すように、ノズル本
体５１としては内径４mmの金属管６を29個、
MgO・Ｃ系の耐火物中に埋設し、ｄφ＝228mm、
Ｄφ＝300mm、Ｌ＝740mmの大きさに構成した。 Next, specific embodiments of the present invention will be described. As shown in the cross-sectional structural diagram in FIG. 6, the nozzle body 51 consists of 29 metal tubes 6 each having an inner diameter of 4 mm.
Buried in MgO/C-based refractory, dφ=228mm,
It was constructed with a size of Dφ=300mm and L=740mm.
キヤツプ５２は0.3〜0.5mm厚の鋼板を用い、ｌ
＝600mm、d0φ＝243mmに形成し、前記ノズル本体
５１の頭部に150mm（＝l0）嵌合せしめ止めビス５
３ａを用いてノズル本体５１に固着した。 The cap 52 is made of a steel plate with a thickness of 0.3 to 0.5 mm.
= 600 mm, d 0 φ = 243 mm, and a screw 5 that fits 150 mm (= l 0 ) into the head of the nozzle body 51.
3a to fix it to the nozzle body 51.
キヤツプ５２の頂部側面には縦ｈ＝20mm、幅ｗ
（弦の長さ）＝150mmのスリツト状の気抜孔５４を
３個設けた。而して、前記底吹ノズル５０におい
てN2ガスを8300／minの流量で噴出せしめてガ
ス吹出し試験を行つた。 The top side of the cap 52 has a height h = 20 mm and a width w.
Three slit-shaped air vent holes 54 each having a length of 150 mm (string length) were provided. Then, a gas blowing test was conducted by blowing out N 2 gas from the bottom blowing nozzle 50 at a flow rate of 8300/min.
この結果、該試験時に噴出ガス圧でキヤツプ５
２が吹き飛ばされることはなく、又ガス圧が異常
に上昇することもなく前記試験が実施できた。さ
らに、不定形耐火物の吹付補修中は底吹ノズル５
０よりN2ガスを5000／minの流量で噴出せしめ
た。 As a result, during the test, the ejected gas pressure caused the cap to 5
The above test could be carried out without any of the gases No. 2 being blown away or the gas pressure increasing abnormally. Furthermore, during the spraying repair of monolithic refractories, the bottom blowing nozzle 5
N 2 gas was ejected from zero at a flow rate of 5000/min.
この結果、不定形耐火物が金属管６に詰まるこ
とは皆無となつた。前記吹付補修が終了し、溶鋼
３を注入するとキヤツプ５２は直ちに溶融し、撹
拌ガスはノズル本体５１の頭部より均等に噴出さ
れ撹拌効率を高めることが可能となつた。 As a result, there was no possibility that the metal tube 6 would be clogged with the monolithic refractory. When the spraying repair was completed and the molten steel 3 was injected, the cap 52 melted immediately, and the stirring gas was evenly jetted out from the head of the nozzle body 51, making it possible to increase the stirring efficiency.
以上のように本考案の実用的効果は非常に大で
あつた。 As described above, the practical effects of the present invention were very large.
尚、本考案における底吹ノズル５０は前記実施
例に限定されるものでないことは当然であり、前
述した本考案の機能を損わない範囲で適宜設計し
用いればよい。例えば気抜孔５４はガス吹出し試
験および吹付補修時のガス噴出量に応じてその大
きさ、形状、数量等を適宜設定すればよく、又キ
ヤツプ５２の板厚や材質を適宜変更することによ
り溶鋼３によつては容易に溶解するが、補修用の
溶融スラグでは溶解しないものに構成すれば前述
した溶融スラグによる補修および不定形耐火物を
流し込み、あるいは充填する補修手段にも用いる
ことが可能である。 It should be noted that the bottom blowing nozzle 50 of the present invention is of course not limited to the above-mentioned embodiments, and may be appropriately designed and used within the range that does not impair the functions of the present invention described above. For example, the size, shape, quantity, etc. of the air vent hole 54 may be appropriately set according to the amount of gas ejected during a gas blowing test and spray repair, and the thickness and material of the cap 52 may be appropriately changed to remove the molten steel. However, if it is made of a material that does not dissolve in the molten slag used for repairs, it can be used for repairs using molten slag as described above, as well as for repair methods such as pouring or filling monolithic refractories. .
しかしながら本考案者等の経験では、低流量域
で高精度の吹込み制御が要求される底吹ノズル、
即ち前記実施例で示すような細径の吹出口、ある
いは金属管６を埋設したものにおいては、僅かな
詰まりが生じても撹拌効率に大きな影響を与え
る。従つて、係かるノズルに対し、しかもノズル
に対しほゞ直角に近い方向から不定形耐火物を吹
付ける補修手段に対して本考案の実用的効果は特
に顕著であつた。 However, in the experience of the present inventors, bottom-blowing nozzles that require high-precision blowing control in low flow areas,
That is, in the case of a small-diameter outlet or one in which a metal tube 6 is buried as shown in the above embodiment, even a small amount of clogging has a large effect on the stirring efficiency. Therefore, the practical effects of the present invention are particularly remarkable for repairing means for spraying monolithic refractories onto such nozzles, particularly from a direction substantially perpendicular to the nozzles.
第１図は周知の一般的な上底吹転炉を示す断面
構造図、第２図は本出願人が先に発明し出願した
底吹ノズルとその装着状況を示す断面構造図、第
３図は底吹ノズル取替後の炉底煉瓦壁損耗状況を
示す部分断面構造図、第４図〜第６図は本考案の
実施例を示すもので、第４図は底吹ノズルの斜視
図、第５図は底吹ノズル装着後の補修状況図、第
６図は底吹ノズルの断面構造図である。
１は転炉、２は上吹ランス、３は溶鋼、４は炉
内煉瓦壁、５は底吹ノズル、６は金属管、７はガ
ス供給管、８はヘツダー部、９は損耗部、１０は
吹付ノズル、１１は耐火層、４０は炉底煉瓦壁、
４０ａは炉底煉瓦、４１は羽口煉瓦、４２，４３
は羽口押え煉瓦、５０は本考案の底吹ノズル、５
１はノズル本体、５１ａは頭部、５１ｂは頭面、
５２はキヤツプ、５２ａは空間、５３は止具、５
３ａは止めビス、５４は気抜孔。
Fig. 1 is a cross-sectional structural diagram showing a well-known general top-bottom blowing converter, Fig. 2 is a cross-sectional structural diagram showing a bottom-blowing nozzle that the applicant previously invented and applied for, and how it is installed. is a partial cross-sectional structural view showing the state of wear and tear on the bottom brick wall after replacing the bottom blowing nozzle; FIGS. 4 to 6 show examples of the present invention; FIG. 4 is a perspective view of the bottom blowing nozzle; FIG. 5 is a diagram of the repair situation after the bottom blowing nozzle is installed, and FIG. 6 is a cross-sectional structural diagram of the bottom blowing nozzle. 1 is a converter, 2 is a top blowing lance, 3 is molten steel, 4 is a brick wall in the furnace, 5 is a bottom blowing nozzle, 6 is a metal pipe, 7 is a gas supply pipe, 8 is a header part, 9 is a worn part, 10 is a spray nozzle, 11 is a fireproof layer, 40 is a hearth brick wall,
40a is a hearth brick, 41 is a tuyere brick, 42, 43
5 is the tuyere presser brick, 50 is the bottom blowing nozzle of the present invention, 5
1 is the nozzle body, 51a is the head, 51b is the head,
52 is a cap, 52a is a space, 53 is a stopper, 5
3a is a set screw, and 54 is a vent hole.
Claims (1)
ヤツプを頭部に固着してなる、転炉底吹ノズル。 A converter bottom-blowing nozzle consisting of an easily soluble cylindrical cap with a vent hole formed on the top side and fixed to the head.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2513283U JPS59133652U (en) | 1983-02-24 | 1983-02-24 | Converter bottom blowing nozzle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2513283U JPS59133652U (en) | 1983-02-24 | 1983-02-24 | Converter bottom blowing nozzle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59133652U JPS59133652U (en) | 1984-09-07 |
| JPS629315Y2 true JPS629315Y2 (en) | 1987-03-04 |
Family
ID=30156135
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2513283U Granted JPS59133652U (en) | 1983-02-24 | 1983-02-24 | Converter bottom blowing nozzle |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59133652U (en) |
-
1983
- 1983-02-24 JP JP2513283U patent/JPS59133652U/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59133652U (en) | 1984-09-07 |
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