JPH0437643Y2

JPH0437643Y2 -

Info

Publication number: JPH0437643Y2
Application number: JP6102887U
Authority: JP
Priority date: 1987-04-21
Filing date: 1987-04-21
Publication date: 1992-09-03
Also published as: JPS63167029U

Description

[Detailed explanation of the idea]

〔産業上の利用分野〕本考案は工業窯炉の耐火ライニング層を火炎溶
射によつて施工あるいは補修を行うための溶射バ
ーナに関するものである。〔従来の技術〕従来、溶射用粉末の火炎溶射に際しては、
LPG，LNG、石油系液体燃料、水素、アセチレ
ン等の燃料の酸素ガスによる燃焼炎の高温ガス体
の中へ粉末を噴射し、個々の粉末が高温ガスの分
子と衝突を繰り返しながら熱交換して溶射用粉末
への熱エネルギーの伝達を行うのが理想的とされ
ていた。そのため、従来の溶射バーナは第３図に示すよ
うな口部形状と第４図に示すような口部断面構造
を有し、火炎口ａの角度はすべて粉末の噴射口ｂ
の前面で相互に交叉し、火炎が相互に衝突する構
造になつている。〔考案が解決しようとする問題点〕このような口部構造を有する火炎溶射バーナに
おいては、高温ガス体中へ粉末ｃが噴射され衝突
が起るため、粉末ｃは飛散し、壁面には比較的広
い範囲に溶射粉末が分散して巾広い溶射体ｄが形
成される。また、微粉状の粉末は火炎の風圧によ
つて四方に飛散し、有効的に対象物に溶着させる
ことができず歩留りが悪く、環境的にも粉塵の発
生による問題がある。とくに、高温工業窯炉の壁面の補修に適用する
場合には、溶射範囲が凹部等の損傷部に集中でき
ず周囲の正常な面にも付着してそこに不必要な凸
状の溶射体を形成する。このため溶射による補修
の場合には、この突出部分をコテ等を用いて突起
部を平滑化する後作業を必要とする。さらに、コ
ークス炉のような壁面をコークス粉が摺動する場
合には、突起部の存在は操業に悪影響を与える。本考案は、従来の溶射バーナにおける溶射粉末
の分散による問題を解決して、溶射粉末の集中性
を改善して、溶射効率が良く、とくに、工業窯炉
の補修に適した火炎溶射バーナを提供することを
目的とする。〔問題点を解決するための手段〕本考案は、従来のガス体との衝突による直接接
触による火炎と粉末との間の熱伝熱を行う溶射バ
ーナを、高温ガス体からの幅射を主たる熱伝熱に
することにより上記の目的を達成したものであ
る。火炎からの幅射伝熱は、火炎層の厚さが厚け
れば厚い程、幅射効率は向上する。従つて、本考
案において溶射バーナの火炎口は粉末の噴射口を
中心にして、２列以上を同心円上に配置してい
る。この構造によつて、粉末と高温ガスの衝突は避
けることができ、２列以上並んだ同心円上に配置
されている火炎口から噴射された火炎が粉末のビ
ームを囲んで、円筒状の炎の壁を形成し、その中
心部を粉末が飛行する状態となり、その溶射粉末
の分散は避けられ集中した箇所に溶射体を形成す
ることができる。その具体的な構造を第１図と第２図に示す実施
例に基づいて説明する。〔実施例〕第１図は本考案の溶射口を底面から見た図であ
り、第２図は第１図の−線から見た断面構造
を示す図である。これらの図を参照して、１は溶射口部の中央部
に配置された粉末の噴射口を示す。同粉末の噴射
口１は単孔でも良いが、噴射粉末流の一定幅内に
おける分散性と熱伝導性のことを考慮すると噴射
口の中心から同心円的に複数個に分岐したものが
望ましく、その場合、それぞれの噴射口１の配置
が中心点に対して点対称であるのが良い。２は粉
末の噴射口１を中心に同心円上に３列に配置され
た火炎口を示す。同火炎口２の数は火炎による粉
末流の包囲搬送の点から各包囲列で８個以上配置
されているのが都合が良い。中心部に最も近い第１番目の同心円上の火炎口
２の放射角は、粉末ビームを撹乱しない程度に中
心部（マイナス方向）に向いた方がよく、その限
界は溶射対象壁面直前がよい。同火炎口２の配置
は、最も中心部に近い位置にある火炎口２が配列
されている円の半径をr₁とし、その同一円周が形
成している平面に直角な垂線と火炎口２との間に
角度（放射角θ₁）が、火炎口２の方向が放射線上
に沿つて外向きの場合をプラスとした場合、 θ₁＞−tan^-1（r₁／200）であることが、耐火物粉末の運搬と熱伝導上最も
好ましい。さらに、第２番目以降の同心円上の火炎口２の
放射角は、他の番目の放射角と相互に交叉しない
ように設定しなければならない。第２番目以降の
同心円上の火炎口２の放射角が相互に交叉した場
合、火炎の流れを乱し、粉末ビームを広げ、また
火炎層が薄くなり幅射効率が低下する。また、発
塵が激化する。個の同一円周上に配置されている火炎口２の
中で中心部から数えて、２番目の列の放射角をθ₂
とし、３番目の列の放射角をθ₃とした場合、一般
には番目の列の放射角をθとし、 θ≧θ_-1≧・・・θ₃≧θ₂≧０の条件をみたしたときに、通常の炉の耐火物のラ
イニングを施す上で、さらに好ましい溶射条件を
得ることができる。溶射バーナ面から溶射対象壁面までの距離は、
バーナ構造によつて異なるが、一般に200〜350mm
であり、その範囲内で火炎と粉末ビームが交叉す
る場合、粉末ビームは大きくは乱されない。同一円周上の火炎口の数は、少なくとも８個以
上必要で、それ以下だと均一な円筒状の炎の壁を
形成し得ない。上記添付図に示す溶射バーナにおいて同一円周
上に2.5mmφの火炎口２を12個配置して、耐火物
ライニングの溶射施工を以下の条件で行つた。中
心部に最も近い第１番目の同心円周上に火炎口２
は中心部に向かつて傾いており、放射角−3°、第
２番目の同一円周上の火炎口２の放射角は外に向
かつており、放射角は＋5°、第３番目の同一円周
上の火炎口２の放射角も外に向かつており、放射
角は＋10°である。 [Industrial Application Field] This invention relates to a flame spray burner for applying or repairing a refractory lining layer of an industrial kiln by flame spraying. [Prior Art] Conventionally, in flame spraying of a powder for flame spraying,
It was considered ideal to inject powder into the high-temperature gas of the combustion flame of oxygen gas of fuel such as LPG, LNG, petroleum-based liquid fuel, hydrogen, acetylene, etc., and transfer thermal energy to the powder for thermal spraying by heat exchange while repeatedly colliding with the molecules of the high-temperature gas. For this reason, conventional thermal spray burners have a nozzle shape as shown in Fig. 3 and a nozzle cross-sectional structure as shown in Fig. 4, and the angle of the flame nozzle a is always the same as that of the powder injection nozzle b.
The flames cross each other at the front of the nozzle and collide with each other. [Problems to be solved by the invention] In a flame spray burner having such a nozzle structure, the powder c is injected into the high-temperature gas body and collides with it, so that the powder c scatters and the spray powder is dispersed over a relatively wide area on the wall surface to form a wide spray body d. In addition, the fine powder scatters in all directions due to the wind pressure of the flame, and it cannot be effectively welded to the target object, resulting in a low yield and environmental problems due to the generation of dust. In particular, when applied to repairing the wall surface of a high-temperature industrial furnace, the spray range cannot be concentrated on the damaged area such as a recess, and it adheres to the surrounding normal surface as well, forming an unnecessary convex spray body there. For this reason, in the case of repair by spraying, it is necessary to perform a post-work of smoothing the protruding parts with a trowel or the like. Furthermore, when coke powder slides on the wall surface of a coke oven, the presence of the protruding parts has a negative effect on operation. The present invention aims to provide a flame spray burner that solves the problem of dispersion of spray powder in conventional spray burners, improves the concentration of spray powder, and has good spray efficiency, particularly suitable for repairing industrial kilns. [Means for solving the problems] The present invention achieves the above-mentioned object by changing the heat transfer between the flame and powder to radiation from a high-temperature gas body, instead of the conventional flame spray burner that transfers heat between the flame and powder by direct contact due to collision with the gas body. The radiation efficiency of the radiation heat transfer from the flame increases as the flame layer becomes thicker. Therefore, in the present invention, the flame ports of the flame spray burner are arranged in two or more rows on a concentric circle around the powder injection port. This structure makes it possible to avoid collision between the powder and high-temperature gas, and the flames injected from the flame ports arranged in two or more rows on a concentric circle surround the powder beam to form a cylindrical flame wall, and the powder flies through the center of the wall, preventing the dispersion of the spray powder and forming a spray body in a concentrated area. The specific structure will be described based on the embodiment shown in Fig. 1 and Fig. 2. [Embodiment] Fig. 1 is a bottom view of the spray nozzle of the present invention, and Fig. 2 is a cross-sectional view taken along line - in Fig. 1. Referring to these figures, 1 shows a powder nozzle arranged at the center of the spray nozzle. The powder nozzle 1 may be a single hole, but considering the dispersibility and thermal conductivity of the sprayed powder flow within a certain width, it is preferable that the nozzle is branched into a plurality of nozzles concentrically from the center of the nozzle. In this case, it is preferable that the nozzles 1 are arranged in point symmetry with respect to the center point. 2 shows flame nozzles arranged in three rows on concentric circles centered on the powder nozzle 1. It is preferable that the number of the flame nozzles 2 is eight or more in each surrounding row from the viewpoint of the surrounding and transporting of the powder flow by the flame. The radiation angle of the first concentric flame nozzle 2 closest to the center should be directed toward the center (negative direction) so as not to disturb the powder beam, and the limit is immediately before the wall surface of the object to be sprayed. The arrangement of the flame nozzles 2 is most preferable in terms of transport and heat conduction of refractory powder. The radius of the circle on which the flame nozzles 2 closest to the center are arranged is _r1 , and the angle (radiation angle _θ1 ) between the flame nozzles 2 and a perpendicular line perpendicular to the plane formed by the same circumference is positive when the direction of the flame nozzles ₂ faces outward along the radial line. In addition, the radiation ^angles of the flame nozzles ₂ on the second and subsequent concentric circles must be set so that they do not cross the radiation angles of the other nozzles. If the radiation angles of the flame nozzles 2 on the second and subsequent concentric circles cross each other, the flame flow will be disturbed, the powder beam will be expanded, the flame layer will become thinner, and the radiation efficiency will decrease. In addition, dust generation will be intensified. If the radiation angle of the second row of the flame nozzles 2 arranged on the same circumference, counting from the center, is set to _θ2
When the radiation angle of the third row is _θ , and the radiation angle of the third row is θ, more preferable spraying conditions can be obtained for applying refractory lining to a normal furnace when the following condition is satisfied: θ≧θ _-1 ≧ ... θ ₃ ≧θ ₂ ≧ 0. The distance from the spray burner surface to the wall surface to be sprayed is
Varies depending on burner structure, but generally 200-350mm
If the flame and powder beam intersect within this range, the powder beam is not significantly disturbed. At least eight flame ports on the same circumference are necessary; if there are fewer than that, a uniform cylindrical flame wall cannot be formed. In the thermal spray burner shown in the attached diagram above, 12 flame ports 2 with a diameter of 2.5 mm were arranged on the same circumference, and the thermal spraying of the refractory lining was carried out under the following conditions. Flame ports 2 were arranged on the first concentric circumference closest to the center.
The first flame nozzle 2 on the same circumference is tilted toward the center with a radiation angle of -3°, the second flame nozzle 2 on the same circumference has a radiation angle pointing outward with a radiation angle of +5°, and the third flame nozzle 2 on the same circumference also has a radiation angle pointing outward with a radiation angle of +10°.

[Effect of idea]

本考案の溶射バーナにより、局部的な溶射による耐火物ライニングの補修
が可能となり、その溶射施工後のコテ作業等の
後作業が不要になつた。溶射粉末の付着率は、従来型の溶射バーナが
85〜90％であつたのが、99％になり、大幅に向
上した。従来型の溶射バーナでは、炉壁面に100×100
mm以上の貫通孔が開くと、溶射補修が不可能で
あつたものが、本考案の溶射バーナでは可能と
なつた。更に、本考案では粉塵の発生がほとんどなく
従つて溶射粉末の付着率も100％になる The thermal spray burner of the present invention makes it possible to repair refractory linings by localized thermal spraying, eliminating the need for post-work such as troweling after thermal spraying. The adhesion rate of thermal spray powder is higher than that of conventional thermal spray burners.
It went from 85-90% to 99%, a significant improvement. In conventional thermal spray burners, 100 x 100
If a through hole of mm or more was opened, thermal spray repair would not be possible, but it has become possible with the thermal spray burner of the present invention. Furthermore, with this invention, there is almost no dust generation, so the adhesion rate of thermal spray powder is 100%.

[Brief explanation of the drawing]

第１図は本考案の溶射バーナの実施例を示す底
面図、第２図は第１図のー線における断面
図、第３図は従来例の底面図、第４図は第３図の
−線における断面図を示す。１……噴射口、２……火炎口、ａ……火炎口、
ｂ……噴射口、ｃ……粉末、ｄ……溶射体。 Fig. 1 is a bottom view showing an embodiment of the thermal spray burner of the present invention, Fig. 2 is a sectional view taken along the - line of Fig. 1, Fig. 3 is a bottom view of the conventional example, and Fig. 4 is a - of Fig. 3. A cross-sectional view taken along the line is shown. 1... injection port, 2... flame port, a... flame port,
b...Injection port, c...Powder, d...Thermal spray body.

Claims

[Scope of utility model registration request]

In a thermal spray burner in which a powder injection port is arranged in the center and flame ports are arranged in at least two or more rows in a concentric circle around the powder injection port in the peripheral part, the powder injection port is placed at the center of the burner. A powder convergence type thermal spray burner characterized in that it is formed by intersecting an extension of the lines.