JP2733885B2 - Continuous heat treatment of steel strip - Google Patents
Continuous heat treatment of steel stripInfo
- Publication number
- JP2733885B2 JP2733885B2 JP4175272A JP17527292A JP2733885B2 JP 2733885 B2 JP2733885 B2 JP 2733885B2 JP 4175272 A JP4175272 A JP 4175272A JP 17527292 A JP17527292 A JP 17527292A JP 2733885 B2 JP2733885 B2 JP 2733885B2
- Authority
- JP
- Japan
- Prior art keywords
- steel strip
- furnace
- burner
- heating
- combustion
- 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
Description
【０００１】[0001]
【産業上の利用分野】この発明は鋼帯の連続熱処理方法
に関する。特に冷延鋼板、ステンレス鋼板の連続焼鈍ラ
イン、電磁鋼板の熱処理ライン、連続熱処理を含む溶融
めっきラインなどに利用されるものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for continuously heat treating steel strip. In particular, it is used for a continuous annealing line for cold rolled steel sheets and stainless steel sheets, a heat treatment line for electrical steel sheets, a hot-dip plating line including continuous heat treatment, and the like.
【０００２】[0002]
【従来の技術】鋼帯の連続熱処理炉の加熱方式として一
般に用いられているのはラジアントチューブによる輻射
加熱法、ゼンジマータイプ溶融亜鉛めっき設備に適用さ
れている鋼帯の側面から直火バーナーにて加熱し、さら
にラジアントチューブにより加熱する方式がある。しか
し最近では走行する鋼帯の表面に直接火炎をあてる直火
バーナー群による効率的な加熱法が実用に供されてい
る。このバーナー群は鋼帯の板幅方向および板の進行方
向に対し数本千鳥状もしくは平行状に並べて配置されて
おり、一例として、鋼帯を加熱するこのバーナーに鋼帯
を酸化せずに加熱する方法として特開昭６４−４０９１
号公報で示される無酸化バーナーを使用したり、また特
開昭６２−５４０３１号公報で示されるように配置する
ことで無酸化加熱を実現している。2. Description of the Related Art A radiant heating method using a radiant tube is generally used as a heating method for a continuous heat treatment furnace for a steel strip. And heating with a radiant tube. However, in recent years, an efficient heating method using a group of direct-fired burners in which a flame is directly applied to the surface of a running steel strip has been put to practical use. The burners are arranged in a zigzag or parallel fashion in the width direction of the steel strip and in the direction in which the strip advances, and as an example, this burner that heats the steel strip is heated without oxidizing the steel strip. Japanese Patent Application Laid-Open No. Sho 64-4091
The non-oxidizing heating is realized by using a non-oxidizing burner disclosed in Japanese Patent Application Laid-Open No. 62-54031 or by disposing it as shown in Japanese Patent Application Laid-Open No. 62-54031.
【０００３】[0003]
【発明が解決しようとする課題】このような鋼帯の直火
加熱炉では鋼帯を無酸化に加熱するためバーナーからの
燃焼火炎を乱さずに鋼帯に当てることが望ましい。燃焼
火炎が乱れると鋼帯が燃焼火炎の還元領域に十分さらさ
れずバーナーが持つ還元能力が低下することがある。直
火加熱炉特に縦型加熱炉では燃焼した排ガスが炉の下部
から上部に向かって流れるため、直火加熱炉の上部加熱
部分に位置するバーナーはその火炎が乱され還元能力が
低下するといった問題がある。このような問題を解決す
るためにバーナーの燃焼により発生した排ガスを火炎に
影響を与えずに排出する方法として特開昭６２−５６９
３３号公報にみられるようにバーナー群より構成される
燃焼ゾーン間を炉壁で仕切り下部からの排ガスが上部ゾ
ーンに侵入して影響を及ぼさない方法や、また燃焼排ガ
ス流路を直火炉の側端に設け、鋼帯の進行する部分には
排ガスを流さず積極的に側面より排出する方法が考案さ
れている。このように直火にて鋼帯を無酸化に加熱する
場合には燃焼排ガスを効率よく排気することで、鋼帯に
対し火炎を乱さずにあて、かつ鋼帯の全面を火炎の還元
領域で覆うようにバーナーを配置する必要があるとされ
ている。In such a steel strip direct-fired heating furnace, it is desirable to apply the steel flame without disturbing the combustion flame from the burner in order to heat the steel strip without oxidation. When the combustion flame is disturbed, the steel strip is not sufficiently exposed to the combustion flame reducing region, and the reducing ability of the burner may be reduced. In an open flame furnace, especially in a vertical furnace, the burned exhaust gas flows from the lower part to the upper part of the furnace. There is. To solve such a problem, Japanese Unexamined Patent Publication No. 62-569 discloses a method of discharging exhaust gas generated by burning a burner without affecting the flame.
As disclosed in Japanese Patent No. 33, a method is used in which a combustion wall constituted by a group of burners is partitioned by a furnace wall so that exhaust gas from the lower part does not enter the upper zone and has no influence. A method has been devised that is provided at the end and actively exhausts the side of the steel strip from the side without letting the exhaust gas flow. When the steel strip is heated non-oxidatively by direct fire in this way, by exhausting the combustion exhaust gas efficiently, the flame is not disturbed to the steel strip, and the entire surface of the steel strip is in the flame reduction region. It is said that it is necessary to arrange a burner to cover.
【０００４】しかしながらこのように燃焼排ガスを効率
良く排気する直火炉では、排ガスが鋼帯に対し十分輻射
伝熱されずに高温のまま排ガス流路に引き込まれ炉外に
放出されるため、直火加熱炉の熱効率が悪い。また火炎
の還元領域で鋼帯を被うために鋼帯の幅が変化した場合
には火炎の燃焼幅を変化させる必要があるが、バーナー
の燃焼幅を鋼帯の幅のすべてに対応して変化させること
は、ガスおよびエアーの遮断、流量調整装置を各バーナ
ーごとに設けておく必要があり、バーナー本数が数百本
におよぶ直火加熱炉では設備費用の観点から好ましくな
いために、通常バーナーを特定の群に分け、エアー、ガ
スを集合ヘッダーにより供給し、そのヘッダーの上流に
設置した流量調整ならびに遮断装置を設け２段階程度の
燃焼幅が変更できる設備とするのが一般的である。しか
しながらこの場合でも必ずしも鋼帯幅とバーナーの燃焼
幅は一致せず、燃焼幅が鋼帯幅に対して広すぎる場合に
は、熱効率が悪いといった問題がある。However, in such a direct-fired furnace that efficiently exhausts the combustion exhaust gas, the exhaust gas is drawn into the exhaust gas channel at a high temperature without being sufficiently radiantly transferred to the steel strip and discharged outside the furnace. Heat efficiency of heating furnace is poor. Also, if the width of the steel strip changes to cover the steel strip in the flame reduction region, it is necessary to change the combustion width of the flame. To change, it is necessary to provide a gas and air shut-off and a flow control device for each burner.Since it is not preferable from the viewpoint of equipment cost in a direct-fired heating furnace with several hundred burners, In general, burners are divided into specific groups, air and gas are supplied by a collective header, and a facility for adjusting the flow rate and a shutoff device installed upstream of the header and capable of changing the combustion width in about two stages is generally used. . However, even in this case, the width of the steel strip does not always match the combustion width of the burner. If the width of the combustion is too wide with respect to the width of the steel strip, there is a problem that thermal efficiency is poor.
【０００５】[0005]
【課題を解決するための手段】この発明は前述の直火加
熱炉における熱効率の悪化の対策として考案したもので
ある。本発明の第一の要旨は、直火加熱炉が予熱炉の出
側に接続され、鋼帯に向かうバーナー群が鋼帯通板方向
に沿って配列された直火加熱炉において、鋼帯の板幅方
向に配置した鋼帯入側のバーナーの燃焼幅を鋼帯幅に対
し狭くし、燃焼の後段になるに従いバーナーの燃焼幅を
広くすることにある。鋼帯の無酸化加熱を確保するため
には鋼帯の全面を火炎の還元領域で覆う必要があるため
加熱の後段では鋼帯を還元火炎で覆う。加熱の前段では
鋼帯の中心部を優先的に加熱し、鋼帯のエッジ部は炉本
体側部に設けた排ガス流路に流れ込む高温の燃焼排ガス
により間接加熱される。SUMMARY OF THE INVENTION The present invention has been devised as a countermeasure against the deterioration of thermal efficiency in the above-mentioned direct fired heating furnace. A first gist of the present invention is a direct-fired heating furnace in which a direct-fired heating furnace is connected to the outlet side of a preheating furnace, and a group of burners directed to the steel strip is arranged along a steel strip passing direction. An object of the present invention is to reduce the combustion width of the burner on the steel strip entry side arranged in the sheet width direction with respect to the steel strip width, and to increase the combustion width of the burner as the stage of combustion becomes later. To ensure the non-oxidizing heating of the strip will covering a steel strip with a reducing flame at a later stage of heating due to the need to cover the entire surface of the steel strip in the reduction zone of the flame. Prior to heating, the central portion of the steel strip is preferentially heated, and the edge of the steel strip is indirectly heated by the high-temperature combustion exhaust gas flowing into the exhaust gas channel provided on the side of the furnace body.
【０００６】[0006]
【作用】鋼帯加熱部分は無酸化加熱を実現させるためバ
ーナーと鋼帯の距離が短く燃焼ガス流路を狭くとる必要
があり、このため燃焼排ガスは抵抗の少ない側部に設け
た排ガス流路に流出し炉下部から上部へドラフトより流
れる。この場合排ガスは鋼帯の中心からエッジ部に多く
流れエッジ部の流速は中心に対し速くなる。したがって
鋼帯のエッジ部は中心部に比べ対流熱伝達係数が高くな
り高温の排ガスにより加熱されることになる。本発明で
はこの効果により加熱の前段部では鋼帯の幅に比べバー
ナーの燃焼幅を狭くして加熱し、加熱の後段では燃焼火
炎で鋼帯を覆い鋼帯を酸化させることなく加熱し、高効
率での加熱を実現した。In order to achieve non-oxidative heating, the distance between the burner and the steel strip must be short and the combustion gas flow path must be narrow in the steel strip heating section. And flows from the lower part of the furnace to the upper part from the draft. In this case, a large amount of exhaust gas flows from the center of the steel strip to the edge portion, and the flow velocity at the edge portion becomes faster than the center. Therefore, the convective heat transfer coefficient of the edge portion of the steel strip is higher than that of the center portion, and the edge portion is heated by the high-temperature exhaust gas. In the present invention, by this effect, heating is performed by narrowing the combustion width of the burner in comparison with the width of the steel strip in the first stage of heating, and in the second stage of heating, the steel strip is covered with a combustion flame and heated without oxidizing the steel strip. Efficient heating was achieved.
【０００７】[0007]
【実施例】図１はこの発明の方法を実施する連続熱処理
設備を併設した溶融めっき設備の炉部の概略構成図であ
る。図１に示すように、連続熱処理設備１は予熱炉２、
直火加熱炉３、均熱炉４、徐冷炉５、および急冷炉６と
から構成されている。直火加熱炉３には無酸化燃焼バー
ナー群が設けられている。図２は直火加熱炉３の断面図
を示す。ここで直火加熱部７にはバーナー群を千鳥状あ
るいは平行状配置し、バーナーの交換ならびに燃料、エ
アーの供給配管の補修等が容易にできるように便宜上分
割してパネル状にして配置した。このバーナーパネル８
は熱処理する鋼帯の処理量およびヒートサイクルに合わ
せて決定するものであり、パネル状に配置する必要性は
特にない。無酸化バーナーはバーナー単独での還元能力
径より決められたピッチにより配置されているため、鋼
帯を酸化させることなく加熱することができている。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic structural view of a furnace part of a hot dip coating facility provided with a continuous heat treatment facility for carrying out the method of the present invention. As shown in FIG. 1, a continuous heat treatment facility 1 includes a preheating furnace 2,
It comprises a direct heating furnace 3, a soaking furnace 4, an annealing furnace 5, and a quenching furnace 6. The non-oxidizing combustion burner group is provided in the direct heating furnace 3. FIG. 2 shows a sectional view of the direct heating furnace 3. Here, the burners were arranged in a staggered or parallel arrangement in the direct fire heating section 7, and were divided into panels for convenience so as to facilitate replacement of the burners and repair of fuel and air supply pipes. This burner panel 8
Is determined according to the throughput of the steel strip to be heat-treated and the heat cycle, and there is no particular necessity to arrange the steel strip in a panel. Since the non-oxidizing burners are arranged at a pitch determined by the diameter of the reducing capability of the burner alone, the steel strip can be heated without being oxidized.
【０００８】発明者らが用いたバーナーは鋼帯とバーナ
ーの距離が１５０ｍｍの位置で還元直径２２０ｍｍのも
のを使用した。処理する鋼帯の板幅は最大１６００ｍｍ
であるため、このバーナーの特性によりバーナーピッチ
は鋼帯の幅方向に２２０ｍｍピッチで最大８本、鋼帯の
進行方向に対して４段で１つのバーナーパネルを構成
し、パネルは鋼帯の表裏に片面各５つ連続して配置し
た。バーナーパネルの側面にはバーナーからの燃焼排ガ
スによりバーナーの還元加熱能力が低下しないため、排
ガスの流路９を設けている。この煙道は下部のバーナー
から発生した排ガスのドラフトにより上部パネルのバー
ナーの火炎が乱され、鋼帯の還元加熱性能が落ちること
を防止するために設けられている。鋼帯走行路の断面積
は０．５ｍ2、排ガス流路は１．３ｍ2 とした。The burner used by the inventors used a steel strip having a reduced diameter of 220 mm at a position where the distance between the steel strip and the burner was 150 mm. The maximum width of the steel strip to be processed is 1600mm
Therefore, due to the characteristics of this burner, a maximum of eight burner pitches are formed at 220 mm pitch in the width direction of the steel strip, and one burner panel is formed in four steps in the traveling direction of the steel strip. , Five on each side. An exhaust gas flow path 9 is provided on the side surface of the burner panel because the combustion heating exhaust gas from the burner does not reduce the reduction heating capability of the burner. This flue is provided in order to prevent the flame of the burner of the upper panel from being disturbed by the draft of the exhaust gas generated from the lower burner, and to prevent the reduction heating performance of the steel strip from deteriorating. The cross section of the steel strip running path was 0.5 m 2 , and the exhaust gas flow path was 1.3 m 2 .
【０００９】このようなバーナーをパネル状にして配置
した直火加熱炉の例で、バーナーを配置したパネルを燃
焼ゾーンと定義し、鋼帯の走行方向に対し加熱炉前段部
から順番に１から５ゾーンとした場合、鋼帯の板幅を１
３００ｍｍ時には各ゾーンの燃焼幅を表１の通りにす
る。この際１ゾーンではエッジ部の排ガス流速が中心部
に比ベ約５倍程早くなっており、これによる対流熱伝達
率は中心部に比べ約３倍になっている。この場所の排ガ
スの温度は約１２００℃でありこの温度領域では輻射に
よる伝熱が支配的であるが、エッジ部の対流伝熱の増加
により火炎の幅が板幅より狭くても幅方向の温度偏差が
無く加熱が可能となっている。[0009] In an example of a direct fired heating furnace in which such burners are arranged in a panel shape, the panel in which the burners are arranged is defined as a combustion zone, and from the front of the heating furnace in the running direction of the steel strip in order from 1 to 1. In the case of 5 zones, the width of the steel strip is 1
At 300 mm, the combustion width of each zone is as shown in Table 1. At this time, in one zone, the exhaust gas flow velocity at the edge is about five times faster than that at the center, and the convective heat transfer coefficient is about three times higher than that at the center. The temperature of the exhaust gas at this location is about 1200 ° C, and in this temperature range, heat transfer by radiation is dominant. However, even if the width of the flame is narrower than the plate width due to the increase of convective heat transfer at the edge, the temperature in the width direction Heating is possible without deviation.
【００１０】バーナーの幅方向の燃焼負荷を変化させる
方法として、図３（ａ）及び図３（ｂ）にその一例を示
す。図３（ａ）はバーナー燃焼幅変更方式による加熱方
式を示す。ここで図３（ｂ）はバーナーを燃焼している
ゾーンを示す。また図４は幅方向の燃焼負荷分布を示
す。バーナーの容量は定格５００００ｋｃａｌ／ｈのも
のを使用し、板幅の中心部約７０％は定格容量で燃焼し
板エッジ部になるに従い徐々に容量を落としエッジ部は
３００００ｋｃａｌ／ｈとした。この場合でもエッジ部
の排ガス流速が速いため鋼帯の幅方法の温度偏差が無く
加熱することができた。FIGS. 3 (a) and 3 (b) show an example of a method of changing the combustion load in the width direction of the burner. FIG. 3A shows a heating method using a burner combustion width changing method. Here, FIG. 3B shows a zone where the burner is burning. FIG. 4 shows the combustion load distribution in the width direction. The burner had a rated capacity of 50,000 kcal / h. About 70% of the center of the plate width was burned at the rated capacity and gradually decreased as the plate edge became lower, and the edge portion was set at 30,000 kcal / h. Even in this case, since the exhaust gas flow rate at the edge portion was high, heating could be performed without a temperature deviation in the width method of the steel strip.
【００１１】[0011]
【表１】 [Table 1]
【００１２】[0012]
【発明の効果】この発明によれば、直火加熱炉において
加熱効率を良くする方法としてバーナーの燃焼幅を鋼帯
の幅のすべてに対応して変化させるために、ガスおよび
エアーの遮断、流量調整装置をバーナーごとに設けてお
く必要がなくなり、設備費の低減を図ることが可能とな
った。また燃焼排ガスの熱量を効率よく鋼帯に伝えるた
め直火加熱炉の平均熱効率を燃焼幅を変更させない場合
に比べ約７％向上させることが可能となった。According to the present invention, as a method for improving the heating efficiency in a direct fired heating furnace, in order to change the combustion width of the burner corresponding to all the widths of the steel strip, the gas and the air are cut off and the flow rate is reduced. It is no longer necessary to provide an adjusting device for each burner, and it is possible to reduce equipment costs. In addition, in order to efficiently transmit the calorific value of the combustion exhaust gas to the steel strip, the average thermal efficiency of the direct-fired heating furnace can be improved by about 7% as compared with a case where the combustion width is not changed.
【図１】この発明の直火加熱炉を具備した連続熱処理炉
設備の概略構成図FIG. 1 is a schematic configuration diagram of a continuous heat treatment furnace equipped with a direct-fired heating furnace according to the present invention.
【図２】直火加熱炉の断面図FIG. 2 is a cross-sectional view of a direct heating furnace.
【図３】（ａ）はバーナー燃焼幅変更方式による加熱方
式、（ｂ）は鋼帯エッジ部のバーナーをターンダウンし
て使用した場合の模式図3 (a) is a heating method using a burner combustion width changing method, and FIG. 3 (b) is a schematic diagram when a burner at a steel strip edge is turned down and used.
【図４】バーナーの幅方向燃焼負荷の分布図である。FIG. 4 is a distribution diagram of a combustion load in a width direction of a burner.
１ 連続熱処理設備 ２ 予熱炉 ３ 直火加熱炉 ４ 均熱炉 ５ 冷却炉 ６ 急冷炉 ７ 直火加熱部 ８ バーナーパネル Reference Signs List 1 continuous heat treatment equipment 2 preheating furnace 3 direct heating furnace 4 soaking furnace 5 cooling furnace 6 quench furnace 7 direct heating section 8 burner panel
───────────────────────────────────────────────────── フロントページの続き (72)発明者 遠田 祐治 千葉県君津市君津１番地 新日本製鐵株 式会社 君津製鐵所内 (72)発明者 長谷 政孝 福岡県北九州市戸畑区大字中原46−59 新日本製鐵株式会社 機械・プラント事 業部内 (72)発明者 松浦 泰夫 福岡県北九州市戸畑区大字中原46−59 新日本製鐵株式会社 機械・プラント事 業部内 (56)参考文献 特開 昭51−105908（ＪＰ，Ａ) ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Yuji Toda 1 Kimitsu, Kimitsu-shi, Chiba Nippon Steel Corporation Kimitsu Works (72) Inventor Masataka Hase 46-59 Nakahara, Tohara-ku, Kitakyushu-shi, Fukuoka Prefecture Nippon Steel Corporation Machinery & Plant Division (72) Inventor Yasuo Matsuura 46-59 Ohara Nakahara, Tobata-ku, Kitakyushu-shi, Fukuoka Nippon Steel Corporation Machinery & Plant Division (56) References JP 51-105908 (JP, A)
Claims (2)
び進行方向に対し複数のバーナーを具備した直火加熱炉
により構成される鋼帯の連続熱処理炉において、前記直
火加熱炉のバーナーの鋼帯の幅方向の燃焼本数を、加熱
の前段は鋼帯よりも狭くなる本数だけ燃焼させ、加熱の
後段にかけて燃焼本数を増やし、少なくとも最終段のバ
ーナー列の燃焼火炎幅を鋼帯の幅より広くすることを特
徴とする鋼帯の連続熱処理方法。1. A continuous heat treatment furnace for a steel strip comprising a preheating furnace and an open flame heating furnace having a plurality of burners in a width direction and a traveling direction on an outlet side of the preheating furnace, wherein the burner of the direct heating furnace is used. The number of burns in the width direction of the steel strip in the width direction of the steel strip is reduced by the number that becomes narrower than the steel strip in the first stage of heating, and the number of combustion is increased in the latter stage of heating. A method for continuously heat-treating a steel strip, characterized by making it wider.
たバーナーの燃焼負荷を炉中心部を高負荷とし、板エッThe burn load of the burner was increased at the center of the furnace,
ジ部を低負荷とすることを特徴とする請求項１記載の鋼2. The steel according to claim 1, wherein the joint has a low load.
帯の連続熱処理方法。Continuous heat treatment method for the belt.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4175272A JP2733885B2 (en) | 1992-07-02 | 1992-07-02 | Continuous heat treatment of steel strip |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4175272A JP2733885B2 (en) | 1992-07-02 | 1992-07-02 | Continuous heat treatment of steel strip |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0617148A JPH0617148A (en) | 1994-01-25 |
| JP2733885B2 true JP2733885B2 (en) | 1998-03-30 |
Family
ID=15993244
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4175272A Expired - Lifetime JP2733885B2 (en) | 1992-07-02 | 1992-07-02 | Continuous heat treatment of steel strip |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2733885B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103305745B (en) * | 2012-03-09 | 2016-04-27 | 宝山钢铁股份有限公司 | A kind of production method of high quality silicon steel normalizing substrate |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51105908A (en) * | 1975-03-13 | 1976-09-20 | Chugai Ro Kogyo Kaisha Ltd | KOTAINOTAIRYUREIKYAKU OYOBI KANETSUSOCHI |
-
1992
- 1992-07-02 JP JP4175272A patent/JP2733885B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0617148A (en) | 1994-01-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1230332A (en) | Induction heaters to improve transitions in continuous heating systems, and method | |
| CN112029972A (en) | Method and system for improving low-temperature non-oxidation heat treatment of radiant tube type roller hearth furnace | |
| US3920382A (en) | Method and apparatus for heat treating articles in a recirculating type furnace | |
| US4069008A (en) | Method and apparatus for heating a workpiece | |
| JPS6327411B2 (en) | ||
| JP2733885B2 (en) | Continuous heat treatment of steel strip | |
| KR100785255B1 (en) | Improvements to the preheating of metal strip, especially in galvanizing or annealing lines | |
| JP4987689B2 (en) | Direct-fired type roller hearth continuous heat treatment furnace | |
| CN100577826C (en) | Direct combustion type metallic tube bright heat treatment method | |
| JPS6344805B2 (en) | ||
| JP3845194B2 (en) | Heating operation method of steel for continuous hot rolling | |
| KR950005790B1 (en) | Method of blackening treating stainless steel strip surface | |
| RU2139944C1 (en) | Method for firing furnace with chambers for preliminary and final heating of metal and furnace for performing the same | |
| JP3067465B2 (en) | Continuous heating furnace | |
| JPH08291328A (en) | Continuous heating apparatus | |
| CN101435018B (en) | Hot dip galvanizing annealing process and high temperature annealing furnace | |
| JPH0553848B2 (en) | ||
| JPH07126759A (en) | Method for heating metallic strip and device therefor | |
| JP3289296B2 (en) | Heating furnace heating method | |
| RU2171960C2 (en) | Furnace for thermal and chemical treatment of metalware in controlled atmosphere and method of its heating | |
| JP3003062B2 (en) | Heating method of billet in continuous heating furnace | |
| JPS6233006Y2 (en) | ||
| JPH0230720A (en) | Method for heating steel sheet | |
| JPH0781167B2 (en) | Direct-fire continuous annealing method and apparatus for steel strip | |
| JPS6160899B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19971202 |