JPH046224A - Method for controlling temperature of continuous annealing furnace - Google Patents
Method for controlling temperature of continuous annealing furnaceInfo
- Publication number
- JPH046224A JPH046224A JP10788990A JP10788990A JPH046224A JP H046224 A JPH046224 A JP H046224A JP 10788990 A JP10788990 A JP 10788990A JP 10788990 A JP10788990 A JP 10788990A JP H046224 A JPH046224 A JP H046224A
- Authority
- JP
- Japan
- Prior art keywords
- steel strip
- dummy
- annealing
- furnace
- temperature
- 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.)
- Granted
Links
- 238000000137 annealing Methods 0.000 title claims abstract description 71
- 238000000034 method Methods 0.000 title claims abstract description 21
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 120
- 239000010959 steel Substances 0.000 claims abstract description 120
- 230000007704 transition Effects 0.000 claims description 6
- 239000007789 gas Substances 0.000 abstract description 19
- 239000000567 combustion gas Substances 0.000 abstract description 3
- 239000000463 material Substances 0.000 description 11
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 10
- 229910052802 copper Inorganic materials 0.000 description 10
- 239000010949 copper Substances 0.000 description 10
- 229910001220 stainless steel Inorganic materials 0.000 description 9
- 239000010935 stainless steel Substances 0.000 description 8
- 230000002950 deficient Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 238000010521 absorption reaction Methods 0.000 description 5
- 238000007796 conventional method Methods 0.000 description 4
- 238000007562 laser obscuration time method Methods 0.000 description 3
- 229920006395 saturated elastomer Polymers 0.000 description 3
- 239000002436 steel type Substances 0.000 description 3
- 238000001816 cooling Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 229910000963 austenitic stainless steel Inorganic materials 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000003507 refrigerant Substances 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
Landscapes
- Control Of Heat Treatment Processes (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は連続焼鈍炉の炉温制御方法に係り、特に焼鈍条
件の異なる先行鋼帯と後行鋼帯の間にダミー鋼帯を介在
させ焼鈍する際の炉温制御方法に関し、ステンレス冷延
鋼帯等の連続焼鈍に広く利用される。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for controlling the furnace temperature of a continuous annealing furnace, and in particular, a dummy steel strip is interposed between a leading steel strip and a trailing steel strip having different annealing conditions. Regarding the furnace temperature control method during annealing, it is widely used for continuous annealing of cold rolled stainless steel strips, etc.
ステンレス冷延鋼帯の連続焼鈍ラインでは、通常需要者
の多種多様の要望に応するため、鋼種、寸法とも多種多
様の銅帯を通板して処理しなければならない。一方、製
造コスト低減のためには同一もしくは近似の鋼種、製品
板材の厚さ、幅等の焼鈍条件の差異の少い銅帯を継続生
産することが望ましい。In a continuous annealing line for cold-rolled stainless steel strips, copper strips of a wide variety of steel types and sizes must be passed through and processed in order to meet the diverse demands of users. On the other hand, in order to reduce manufacturing costs, it is desirable to continue producing copper strips of the same or similar steel type and with little difference in annealing conditions such as product sheet thickness and width.
従って連続焼鈍ラインでは通常先行鋼帯の後端に、ヒー
トパターン、焼鈍温度、板厚、板幅、鋼種、放射率等の
焼鈍条件に大幅な差異を生じないように後行鋼帯を選択
して接続し、連続焼鈍を実施することがコスト低減のた
めに最も望ましい。Therefore, in a continuous annealing line, the trailing steel strip is usually selected at the trailing end of the leading steel strip so that there are no significant differences in annealing conditions such as heat pattern, annealing temperature, plate thickness, plate width, steel type, and emissivity. To reduce costs, it is most desirable to perform continuous annealing.
しかし、納期等の理由から、上記関係の持続が保てず、
大幅に焼鈍条件が異なる後行鋼帯を組合わせなければな
らないことがしばしば起る。However, due to delivery deadlines and other reasons, the above relationship could not be maintained.
It often happens that trailing steel strips with significantly different annealing conditions must be combined.
このような場合には第１図に示す如く、先行鋼帯Ａと、
後行鋼帯Ｃとの間に、長さ数百メートルのダミー鋼帯Ｂ
を介在させて、該ダミー鋼帯Ｂを通板中に連続焼鈍炉の
炉温を後行鋼帯Ｃの焼鈍条件に調整した後、後行鋼帯Ｃ
の焼鈍を行なうのが現状である。In such a case, as shown in Fig. 1, the preceding steel strip A,
A dummy steel strip B with a length of several hundred meters is placed between the trailing steel strip C and the trailing steel strip C.
After adjusting the furnace temperature of the continuous annealing furnace to the annealing conditions of the trailing steel strip C while passing the dummy steel strip B,
Currently, annealing is performed.
一方、通常用いられる連続焼鈍炉１は、第２図に示す如
く加熱帯、均熱帯、冷却帯等数ゾーンから構成されてお
り、各ゾーン毎にゾーン温度を熱電対２および温度制御
装置３を介して制御できるようになっている。すなわち
、各ゾーン毎に炉の温度を上げる場合には１例えば直火
式であれば燃焼ガス量４を増加する等、熱エネネギーの
投入を増加し、逆に炉温を下げる場合には、熱エネルギ
ーの投入量を減じるとか、更に急冷する場合には冷媒を
投入する等の操作によって炉温を各ゾーン毎に目標とす
る温度に調整する。On the other hand, a commonly used continuous annealing furnace 1 is composed of several zones, such as a heating zone, a soaking zone, and a cooling zone, as shown in FIG. It can be controlled via. In other words, when increasing the furnace temperature in each zone, input of thermal energy is increased (1, for example, if it is a direct-fired type, the amount of combustion gas is increased), and conversely, when decreasing the furnace temperature, the input of heat energy is increased. The furnace temperature is adjusted to the target temperature for each zone by reducing the amount of energy input or, for more rapid cooling, by adding refrigerant.
かくの如き各ゾーンの温度制御の目的は、処理材料の銅
帯を最適のヒートパターンに合致する温度値に制御する
ことであり、通常直接材料温度を測定してヒートパター
ンが所望の温度値になるように熱エネルギーの投入量を
制御して焼鈍することが望ましい。しかし、ステンレス
鋼帯の焼鈍温度は９００℃以上と高温であるほか、銅帯
表面の熱吸収率は０．３〜０．４程度と、きわめて低い
ので、搬送されているステンレス鋼帯の表面温度を工業
的に精度よく測定する測温装置は未だ開発されていない
現状である。The purpose of such temperature control in each zone is to control the copper strip of the material being processed to a temperature value that matches the optimum heat pattern, usually by directly measuring the material temperature to ensure that the heat pattern reaches the desired temperature value. It is desirable to perform annealing by controlling the input amount of thermal energy so that the following results are obtained. However, the annealing temperature of the stainless steel strip is high at 900°C or higher, and the heat absorption rate of the surface of the copper strip is extremely low at about 0.3 to 0.4, so the surface temperature of the stainless steel strip being transported is At present, a temperature measuring device that can accurately measure temperature has not yet been developed on an industrial scale.
従って、ステンレス鋼帯の連続焼鈍は、通常炉温と板温
との間のデータを実験的に数多く求めておき、両者間の
相関関係を知り、工業的な熱処理に適用している。すな
わち、処理材を目標とするヒートパターンおよび板温ど
おりに焼鈍しようとする場合には、炉温を制御して処理
材の特性に見合ったヒートパターンおよび板温を得る方
法である。この方法によって焼鈍条件の大幅な差異のな
い先行鋼帯Ａと後行鋼帯Ｃの板換わり点における焼鈍条
件の変更を行っている。すなわち、焼鈍炉の各ゾーンの
温度を後行鋼帯Ｃ向けの温度に調整するか、もしくは通
板速度の変更で対処していた。Therefore, in continuous annealing of stainless steel strips, a large amount of data between the furnace temperature and the plate temperature is usually obtained experimentally, the correlation between the two is known, and the data is applied to industrial heat treatment. That is, when it is desired to anneal a treated material to a target heat pattern and sheet temperature, the method is to control the furnace temperature to obtain a heat pattern and sheet temperature that match the characteristics of the treated material. By this method, the annealing conditions are changed at the plate change point of the preceding steel strip A and the following steel strip C, which do not have a significant difference in annealing conditions. That is, this has been dealt with by adjusting the temperature of each zone of the annealing furnace to the temperature for the trailing steel strip C, or by changing the threading speed.
この方法は、板厚、板幅、ライン速度の変動差により、
ガス投入量をその変動差分だけ変更し、炉温か変化しな
いように制御する方法である。This method uses variations in plate thickness, plate width, and line speed to
This is a method of controlling the furnace temperature so that it does not change by changing the amount of gas input by the difference in the amount of gas input.
しかし、上記の如く大幅に焼鈍条件の異なる先行鋼帯Ａ
と後行鋼帯Ｃとの間に介在させるダミー鋼帯Ｂは繰返し
使用され、しかも普通鋼板が使用されるので繰返し使用
中に表面が酸化され、スケールの厚みが次第に厚くなり
表面の色が黒変して熱吸収率が大きくなる傾向がある。However, as mentioned above, the preceding steel strip A has significantly different annealing conditions.
The dummy steel strip B interposed between the steel strip C and the trailing steel strip C is used repeatedly, and since a regular steel plate is used, the surface becomes oxidized during repeated use, and the scale becomes thicker and the color of the surface becomes black. There is a tendency for the heat absorption rate to increase.
一方、銅帯が吸収する熱量Ｑと、その温度Ｔａとの間に
は次の（１）式で示すような関係が成立する。On the other hand, a relationship as shown in the following equation (1) is established between the amount of heat Q absorbed by the copper strip and its temperature Ta.
ここにＱ ： 吸収熱量（Ｋｃａｌ／ｈｒ）Ｋ ： 定
数
φｃａ： 総括熱伝達係数（熱吸収率に相当）ＴＦ
： 炉内温度（℃）
Ｔ８ ： 調書温度（’Ｃ）
Ｑ、： 炉体放散熱（Ｋｃａｌ／ｈｒ）（１）式より明
らかなとおり、一定の投入熱量の場合でも熱吸収率φ。Here, Q: Absorbed heat amount (Kcal/hr) K: Constant φca: Overall heat transfer coefficient (equivalent to heat absorption rate) TF
: Furnace temperature (°C) T8 : Record temperature ('C) Q, : Furnace body dissipated heat (Kcal/hr) As is clear from equation (1), even when input heat is constant, the heat absorption rate φ.
６が小さいほど、銅帯温度Ｔｓが小さく温度が上昇しな
い。逆にφ。Ｇが大きい程銅帯温度が大となり温度が上
昇する。そこで先行鋼帯Ａからダミー鋼帯Ｂへ、更にダ
ミー鋼帯Ｂから後行鋼帯Ｃへの接続部においては、上記
吸収熱量差を補正する制御が行われていたが、従来はダ
ミー材Ｂの総括熱伝達係数は通板回数に関係なく、飽和
した状態と仮定して、例えば第３図に示す如くφ。。＝
０．６としていた。すなわち、前記の如く、使用回数が
多く表面のスケール厚みが厚く表面が黒色になったダミ
ー材も、使用回数が少く製品ステンレス鋼帯に近い表面
光沢を有するダミー材もφ。ａ＝０．６として制御して
いた。そのためダミー鋼帯Ｂから後行の製品鋼帯Ｃに移
行する際に、第４図に示す如く、（１）式により後行製
品鋼帯ＣのＴ、が上昇し、８５０℃から９５０℃に急上
昇することがあった。The smaller 6 is, the smaller the copper band temperature Ts is, and the temperature does not rise. On the contrary, φ. The larger G is, the higher the copper zone temperature becomes, and the temperature rises. Therefore, control was performed to correct the difference in absorbed heat at the connections from the leading steel strip A to the dummy steel strip B, and from the dummy steel strip B to the trailing steel strip C. Assuming that the overall heat transfer coefficient is saturated regardless of the number of passes, the overall heat transfer coefficient is φ as shown in FIG. 3, for example. . =
It was set at 0.6. That is, as mentioned above, both the dummy material that has been used many times and has a thick scale on the surface and a black surface, and the dummy material that has been used few times and has a surface gloss similar to that of a manufactured stainless steel strip. It was controlled by setting a=0.6. Therefore, when moving from dummy steel strip B to the following product steel strip C, T of the following product steel strip C increases from 850°C to 950°C according to equation (1), as shown in Figure 4. There was a sudden rise.
ステンレス鋼は、例えば５ＵＳ４３０では９００℃附近
に変態点があるため９３０℃近くまで温度が上昇すると
製品として使用できずスクラップとしなければならず、
良品率が減少しコストが上昇する。Stainless steel, for example 5US430, has a transformation point around 900°C, so if the temperature rises to around 930°C, it cannot be used as a product and must be scrapped.
The rate of non-defective products decreases and costs increase.
本発明の目的は、焼鈍条件が著しく異なるために、先行
銅帯と後行鋼帯の間にダミー鋼帯を介在させて焼鈍する
連続焼鈍炉における炉温制御方法において、従来、ダミ
ー鋼帯の新、旧に関らず総括熱伝達係数を一定として制
御し、そのために後行製品鋼帯の焼鈍温度を過度に高め
る事故のあることに鑑み、常に安定して適正な焼鈍温度
で焼鈍することができる効果的な炉温制御方法を提供す
るにある。An object of the present invention is to provide a furnace temperature control method for a continuous annealing furnace in which a dummy steel strip is interposed between a leading copper strip and a trailing steel strip because the annealing conditions are significantly different. Regardless of whether it is new or old, the overall heat transfer coefficient is controlled to be constant, and in view of the fact that there have been accidents in which the annealing temperature of subsequent product steel strips is excessively increased, it is necessary to always anneal at a stable and appropriate annealing temperature. The objective is to provide an effective method for controlling furnace temperature.
本発明の要旨とするところは次の如くである。 The gist of the present invention is as follows.
すなわち、
（１）焼鈍条件の異なる先行鋼帯と後行鋼帯の間にダミ
ー鋼帯を介在させ該ダミー鋼帯の通板中に連続焼鈍炉の
炉温を前記後行鋼帯の焼鈍条件に調整する連続焼鈍炉の
温度制御方法において、前記ダミー鋼帯の通板回数に応
じて前記後行鋼帯焼鈍時の熱投入量を制御することを特
徴とする連続焼鈍炉の炉温制御方法。That is, (1) A dummy steel strip is interposed between the leading steel strip and the trailing steel strip, which have different annealing conditions, and the furnace temperature of the continuous annealing furnace is adjusted to the annealing condition of the trailing steel strip during the passing of the dummy steel strip. A continuous annealing furnace temperature control method for adjusting the temperature of a continuous annealing furnace, the method comprising controlling the amount of heat input during annealing of the trailing steel strip according to the number of times the dummy steel strip is passed through. .
（２）連続焼鈍炉における前記ダミー鋼帯の通板から前
記後行鋼帯への移行時のガス投入量変化を△Ｑ （Ｎ
ｒｒｉ’ ／ｈｒ）とすればΔＱ （Ｎｒｎ’／ｈｒ）
＝Ｋｉ（Ｎ）×（Ｆ２−Ｆ２−Ｆｌ）・・・−（１）
ただし Ｋ□（Ｎ）： ダミー鋼帯の通板回数によって
決まる係数
Ｆ２： 後行鋼帯の板厚、板幅、ラ
イン速度の積
Ｆｌ ： ダミー鋼帯の板厚、板幅、
ライン速度の積
（１）式で表される上記（１）に記載の連続焼鈍炉の炉
温制御方法である。(2) The change in gas input amount during the transition from passing the dummy steel strip to the trailing steel strip in the continuous annealing furnace is ΔQ (N
rri'/hr) then ΔQ (Nrn'/hr)
=Ki(N)×(F2-F2-Fl)...-(1)
However, K This is a furnace temperature control method for a continuous annealing furnace according to the above (1), which is expressed by equation (1).
本発明の詳細を添附図面を参照して説明する。The details of the invention will be explained with reference to the accompanying drawings.
焼鈍条件の著しく異なる先行［ＦＡと後行＃ｌ帯Ｃとの
間にダミー鋼帯Ｂを介在させ、該ダミー鋼板Ｂの通板中
に焼鈍条件をＢからＣに調整し後行鋼帯Ｃに最も適した
炉温に制御する方法において、従来介在通板させるダミ
ー鋼帯Ｂの総括熱伝達係数（Ｋｃａｌ／ ｒｒｒｈｒ）
は、第３図に示す如く、例えばφｃ−＝０ 、６として
一定とみなし、後行鋼帯Ｃの炉温を制御していたが、本
発明者らはダミー鋼帯Ｂの総括熱伝達係数は通板回数に
よって変化することを見出した。すなわち新しいダミー
鋼帯Ｂの表面光沢は製品ステンレス鋼帯に近い光沢を有
し熱吸収率が著しく小であることを見出した。これを数
回ないしｌＯ数回通板させてほぼ飽和して一定となった
時の総括熱伝達係数の例えば０．６として後行鋼帯Ｃの
通板時の炉温制御していたことにより、過度の高温焼鈍
を実施するという事故発生に鑑み、本発明は第３図に示
す如く、例えば当初は０．３から始まり、次第に高くな
って通板回数１０回にしてほぼ飽和状態の０．６に達す
るものであることを見出した。A dummy steel strip B is interposed between the leading steel strip C and the trailing steel strip C, and the annealing conditions are adjusted from B to C during the passing of the dummy steel strip C. In the method of controlling the furnace temperature most suitable for
As shown in FIG. 3, the furnace temperature of the trailing steel strip C was controlled by assuming that φc-=0, 6, for example, but the inventors determined that the overall heat transfer coefficient of the dummy steel strip B was found to change depending on the number of passes. That is, it was found that the surface gloss of the new dummy steel strip B was close to that of the product stainless steel strip, and the heat absorption rate was extremely low. This is because the furnace temperature at the time of passing the trailing steel strip C was controlled by setting the overall heat transfer coefficient to 0.6, for example, when the steel was passed several times to 10 times and became almost saturated and constant. In view of the accident that occurred due to excessively high temperature annealing, the present invention, as shown in FIG. 3, starts with, for example, 0.3 at the beginning, and gradually increases to 0.3, which is almost saturated after 10 passes. It was found that it reached 6.
従ってダミー鋼帯Ｂから後行製品鋼帯Ｃに移行する際の
ガス投入量の増大分を△Ｑ （Ｎｒｎ’／ｈｒ）とすれ
ば、下記の（２）式が成立する。Therefore, if the increase in the amount of gas input when transferring from the dummy steel strip B to the subsequent product steel strip C is set to ΔQ (Nrn'/hr), the following equation (2) holds true.
ΔＱ （Ｎｍ／ｈｒ） ＝＝）（１（Ｎ）×（Ｆ２−Ｆ
ｃ Ｆ！＋）””””’（２）ここに Ｋ□（Ｎ）：
ダミー鋼帯Ｂの使用回数によって決まる係数
Ｆｃ ： 後行製品鋼帯Ｃの板厚、板幅、ライン速度
の積
ＦＢ ： ダミー鋼帯Ｂの板厚、板幅、ライン速度の
積
かくの如く、ダミー鋼帯Ｂの通板回数に応じてきめ細か
く投入ガス量を制御することにより、新しいダミー鋼板
を使用時も後行製品鋼帯Ｃの接続する先端部の過度の高
温を防止することができ、後行鋼帯Ｃに適合した焼鈍を
実施することができた。ΔQ (Nm/hr) ==)(1(N)×(F2-F
C F! +)””””’(2) Here K□(N):
Coefficient Fc determined by the number of times dummy steel strip B is used: Product of plate thickness, plate width, and line speed of succeeding product steel strip C FB: Product of plate thickness, plate width, and line speed of dummy steel strip B, By finely controlling the input gas amount according to the number of times the dummy steel strip B is passed through, it is possible to prevent the tip of the succeeding product steel strip C from becoming too hot even when using a new dummy steel strip. Annealing compatible with trailing steel strip C could be carried out.
オーステナイト系ステンレス鋼５ＵＳ３０４の先行鋼帯
Ａからフェライト系ステンレス鋼５ＵＳ４３０の後行ｆ
ｌＩ帯Ｃに移行時に通板回数２回の新しい普通鋼のダミ
ー鋼帯Ｃを介在させて連続焼鈍炉で焼鈍した。Leading steel strip A of austenitic stainless steel 5US304 to trailing steel band F of ferritic stainless steel 5US430
At the time of transition to II band C, a new dummy steel strip C of ordinary steel, which had been passed twice, was interposed and annealed in a continuous annealing furnace.
この際、従来法によりダミー鋼板Ｂの総括熱伝達係数φ
ｃｃ ” ０ 、６’として後行鋼帯Ｃに移行した場合
と、本発明によりダミー鋼板Ｂのφ。。＝０．３として
後行鋼帯Ｃに移行した実施例について比較説明する。At this time, the overall heat transfer coefficient φ of dummy steel plate B was determined using the conventional method.
A comparative explanation will be given of a case where the steel plate is transferred to the trailing steel strip C with cc ” 0, 6′ and an example where the transfer is made to the trailing steel strip C with φ..=0.3 of the dummy steel plate B according to the present invention.
（Ａ）従来法によった場合
９００℃による焼鈍を目標としてダミー鋼板Ｂから後行
鋼帯Ｃへの移行時にφ。ａ”０．６としてガス開度すな
わち、第４図（Ｂ）に示す如く（投入ガス量／最大ガス
量）＝９５％としてガス熱量を投入した処、ダミー鋼帯
Ｂの温度は第４図（Ａ）に示す如く８５０℃まで下り、
後行！ＩＣに移行した当初は、９５０’Ｃまで上昇した
後、数秒間後にようやく目標温度の９００℃に戻ったが
、９５０℃で焼鈍した部分の約５０ｍは、変態点９１０
℃を越す温度であったので、この部分は焼鈍不良品とし
て切断廃棄せざるを得なかった。焼鈍不良品として廃棄
した長さは、後行鋼帯Ｃの全長の約３％であった。(A) When using the conventional method, φ at the time of transition from dummy steel plate B to trailing steel strip C with the goal of annealing at 900°C. When the gas opening is set to a"0.6, that is, the gas calorific value is input with (input gas amount/maximum gas amount) = 95% as shown in Figure 4 (B), the temperature of dummy steel strip B is as shown in Figure 4. As shown in (A), the temperature drops to 850℃,
Follow me! At the beginning of the transition to IC, the temperature rose to 950'C and finally returned to the target temperature of 900'C after a few seconds, but about 50m of the part annealed at 950'C had a transformation point of 910'C.
Since the temperature exceeded 10°C, this part had to be cut and discarded as a defective annealing product. The length that was discarded as an annealing defective product was about 3% of the total length of the trailing steel strip C.
（Ｂ）本発明法によった場合
新しいダミー鋼帯Ｂのφｃｃ ” ０ 、３としてダミ
ー鋼帯Ｂから後行製品鋼帯Ｃに移行時のガス開度は第５
図（Ｂ）に示す如く、４０％であったので、この開度で
移行した処、第５図（Ａ）に示す如くダミー鋼帯Ｂの温
度は８９５℃と低下したが、後行製品鋼帯Ｃへの移行直
後の鋼帯Ｃの温度は、−時９０５℃を示したものの、数
秒後に目標とする９００℃の焼鈍温度となり、焼鈍不良
品ロスは全く発生せず、目標温度の９ｏｏ℃で安定操業
が実施できた。(B) When using the method of the present invention, assuming that φcc of the new dummy steel strip B is 0,3, the gas opening degree at the time of transition from the dummy steel strip B to the succeeding product steel strip C is 5th.
As shown in Figure (B), the temperature of the dummy steel strip B decreased to 895°C as shown in Figure 5 (A) when the transition was made at this opening degree. The temperature of steel strip C immediately after the transition to band C was -905°C, but after a few seconds it reached the target annealing temperature of 900°C, and no loss of defective annealing products occurred, and the target temperature was 900°C. Stable operation was achieved.
新しいダミー材の総括熱伝達係数φ。６は第３図に示す
如く、当初はＱ 、 ３ Ｋｃａｌ／イｈｒであり、約
１ｏ回の通板にて従来採用していた飽和係数値の０ 、
６ Ｋｃａｌ／ｒｒｆｈｒに達することが判明したので
、その後新しいダミー材Ｂは、その通板回数によってφ
ｃａ値を変えて後行鋼帯Ｃへの移行時の、ガス開度（％
）を制御して焼鈍を実施した処、従来より良品歩留を約
３％向上させることができた。Overall heat transfer coefficient φ of new dummy material. 6, as shown in Fig. 3, was initially Q, 3 Kcal/hr, and after about 10 times of threading, the saturation coefficient value of 0, which was conventionally adopted, was changed.
Since it was found that the new dummy material B reached 6 Kcal/rrfhr, the φ
Gas opening degree (%) when transitioning to trailing steel strip C by changing the ca value
), we were able to improve the yield of good products by approximately 3% compared to the conventional method.
先行鋼帯と後行鋼帯の焼鈍条件が著しく異なる連続焼鈍
時に１両者の間にダミー銅帯を介在させてダミー鋼帯の
通板中に後行鋼帯に適合する炉温に調整する連続焼鈍法
において、従来ダミー材の総括熱伝達係数は、その飽和
値に一定として後行鋼帯Ｃの通板時のガス開度を制御し
ていたので。During continuous annealing, where the annealing conditions of the leading steel strip and the trailing steel strip are significantly different, a dummy copper strip is interposed between the two to adjust the furnace temperature to match that of the trailing steel strip while the dummy steel strip is threaded. In the annealing method, conventionally the overall heat transfer coefficient of the dummy material was kept constant at its saturation value and the gas opening degree during the passing of the trailing steel strip C was controlled.
後行製品鋼帯Ｃへの通板移行直後に不適性焼鈍温度によ
る不良品の発生していた原因を探求中の処。We are currently investigating the cause of defective products due to unsuitable annealing temperature immediately after passing to the succeeding product steel strip C.
ダミー材の表面光沢の差による総括熱伝達係数は、その
通板回数により変化し、前記（２）式による関係がある
ことを見出し、これにより移行時のガス開度を調整し投
入熱量を制御する方法をとったので、従来、ダミー鋼帯
Ｂから後行製品鋼帯Ｃへの移行直後に発生していた過度
の炉温上昇による不良品の発生がほとんど解消され、き
め細い制御により適正炉温による安定操業が可能となり
、良品歩留を約３％向上させることができた。It was found that the overall heat transfer coefficient due to the difference in surface gloss of the dummy material changes depending on the number of times the material is passed through, and that there is a relationship according to equation (2) above.From this, the gas opening degree during transfer is adjusted and the amount of heat input is controlled. As a result, the occurrence of defective products due to excessive furnace temperature rise, which conventionally occurred immediately after the transition from dummy steel strip B to succeeding product steel strip C, has been almost eliminated, and fine-grained control allows for proper furnace production. It became possible to operate stably at high temperatures, and the yield of good products was improved by approximately 3%.
第１図は先行鋼帯Ａと後行鋼帯Ｃの間にダミー鋼帯Ｂを
介在させて通板する状況を示す模式断面図、第２図は連
続焼鈍炉と通板鋼帯との関係を示す模式断面図、第３図
はダミー鋼帯の総括熱伝達係数（Ｋｃａｌ／ ｒｒ？ｈ
ｒ）と通板使用回数との関係における従来法と本発明法
との比較を示す線図、第４図（Ａ）、（Ｂ）は本発明法
と従来法との通板比較試験における従来法の試験結果を
示し、（Ａ）は後行製品鋼帯の連続焼鈍炉中の時間の経
過による炉温変化を示す線図、（Ｂ）は（Ａ）の時間の
経過に対応する焼鈍ガス開度％（投入ガス量／最大ガス
ｊｔ）を示す線図、第５図（Ａ）、（Ｂ）はそれぞれ第
４図（Ａ）、（Ｂ）と同様の本発明法による試験結果を
示し、（＾）は後行製品鋼帯の連続焼鈍炉中の時間の経
過による炉温変化を示す線図、（Ｂ）は（Ａ）の時間の
経過に対応する焼鈍ガス開度％（投入ガス量／最大ガス
量）を示す線図である。
Ａ・・・先行鋼帯 Ｂ・・・ダミー鋼帯Ｃ・・・
後行銅帯
１・・・連続焼鈍炉 ２・・・熱電対３・・・温度
制御装置
・・燃焼ガス（燃料）Figure 1 is a schematic sectional view showing the situation in which a dummy steel strip B is interposed between the leading steel strip A and the trailing steel strip C, and Figure 2 is the relationship between the continuous annealing furnace and the threaded steel strip. Figure 3 is a schematic cross-sectional view showing the overall heat transfer coefficient (Kcal/rr?h) of the dummy steel strip.
Figure 4 (A) and (B) are diagrams showing a comparison between the conventional method and the method of the present invention in relation to r) and the number of times of sheet threading. (A) is a diagram showing the furnace temperature change over time in the continuous annealing furnace of the subsequent product steel strip, (B) is a diagram showing the annealing gas corresponding to the passage of time in (A). Diagrams showing opening degree % (input gas amount/maximum gas jt), Figures 5 (A) and (B) show test results by the method of the present invention similar to Figures 4 (A) and (B), respectively. , (^) is a diagram showing the furnace temperature change over time in the continuous annealing furnace of the subsequent product steel strip, (B) is a diagram showing the annealing gas opening % (input gas FIG. A...Advanced steel strip B...Dummy steel strip C...
Trailing copper strip 1... Continuous annealing furnace 2... Thermocouple 3... Temperature control device... Combustion gas (fuel)
Claims (1)
ー鋼帯を介在させ該ダミー鋼帯の通板中に連続焼鈍炉の
炉温を前記後行鋼帯の焼鈍条件に調整する連続焼鈍炉の
温度制御方法において、前記ダミー鋼帯の通板回数に応
じて前記後行鋼帯焼鈍時の熱投入量を制御することを特
徴とする連続焼鈍炉の炉温制御方法。 （２）連続焼鈍炉における前記ダミー鋼帯の通板から前
記後行鋼帯への移行時のガス投入量変化をΔＱ（Ｎｍ＾
３／ｈｒ）とすれば ΔＱ（Ｎｍ＾３／ｈｒ）＝Ｋ＿１（Ｎ）×（Ｆ＿２−Ｆ
＿１）……（１）ただしＫ＿１（Ｎ）：ダミー鋼帯の通
板回数によって決まる係数 Ｆ＿２：後行鋼帯の板厚、板幅、ラ イン速度の積 Ｆ＿１：ダミー鋼帯の板厚、板幅、 ライン速度の積 （１）式で表される請求項（１）に記載の連続焼鈍炉の
炉温制御方法。[Scope of Claims] (1) A dummy steel strip is interposed between a leading steel strip and a trailing steel strip having different annealing conditions, and the furnace temperature of the continuous annealing furnace is adjusted to the temperature of the continuous annealing furnace during the passing of the dummy steel strip. A continuous annealing furnace temperature control method for adjusting the temperature of a continuous annealing furnace to adjust the annealing conditions of the strip, characterized in that the amount of heat input during annealing of the trailing steel strip is controlled according to the number of times the dummy steel strip is passed through. Furnace temperature control method. (2) The change in gas input amount during the transition from passing the dummy steel strip to the trailing steel strip in the continuous annealing furnace is expressed as ΔQ (Nm^
3/hr), then ΔQ(Nm^3/hr)=K_1(N)×(F_2-F
_1)...(1) However, K_1(N): Coefficient determined by the number of times the dummy steel strip is passed F_2: Product of the thickness, width, and line speed of the trailing steel strip F_1: Thickness of the dummy steel strip, plate The furnace temperature control method for a continuous annealing furnace according to claim 1, which is expressed by the product of width and line speed (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2107889A JP2807918B2 (en) | 1990-04-24 | 1990-04-24 | Combustion control method for continuous annealing furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2107889A JP2807918B2 (en) | 1990-04-24 | 1990-04-24 | Combustion control method for continuous annealing furnace |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH046224A true JPH046224A (en) | 1992-01-10 |
| JP2807918B2 JP2807918B2 (en) | 1998-10-08 |
Family
ID=14470645
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2107889A Expired - Fee Related JP2807918B2 (en) | 1990-04-24 | 1990-04-24 | Combustion control method for continuous annealing furnace |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2807918B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100494094B1 (en) * | 2002-11-27 | 2005-06-10 | 주식회사 포스코 | Dummy steel sheet having superior degradation resistance of material for black plate |
| JP2006104492A (en) * | 2004-09-30 | 2006-04-20 | Jfe Steel Kk | Method for producing high tensile cold rolled steel sheet in continuous annealing process |
| CN109321741A (en) * | 2017-07-31 | 2019-02-12 | 湖北华鑫科技股份有限公司 | The automatic annealing machine of precision steel strip |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6070128A (en) * | 1983-09-28 | 1985-04-20 | Nippon Kokan Kk <Nkk> | Method for controlling temperature of strip with continuous annealing furnace |
| JPS61117229A (en) * | 1984-11-13 | 1986-06-04 | Mitsubishi Heavy Ind Ltd | Heating method of continuous annealing furnace for metallic strip |
| JPS6289820A (en) * | 1985-10-14 | 1987-04-24 | Kawasaki Steel Corp | Method for diagnosing apparatus in continuous annealing furnace |
-
1990
- 1990-04-24 JP JP2107889A patent/JP2807918B2/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6070128A (en) * | 1983-09-28 | 1985-04-20 | Nippon Kokan Kk <Nkk> | Method for controlling temperature of strip with continuous annealing furnace |
| JPS61117229A (en) * | 1984-11-13 | 1986-06-04 | Mitsubishi Heavy Ind Ltd | Heating method of continuous annealing furnace for metallic strip |
| JPS6289820A (en) * | 1985-10-14 | 1987-04-24 | Kawasaki Steel Corp | Method for diagnosing apparatus in continuous annealing furnace |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100494094B1 (en) * | 2002-11-27 | 2005-06-10 | 주식회사 포스코 | Dummy steel sheet having superior degradation resistance of material for black plate |
| JP2006104492A (en) * | 2004-09-30 | 2006-04-20 | Jfe Steel Kk | Method for producing high tensile cold rolled steel sheet in continuous annealing process |
| JP4586479B2 (en) * | 2004-09-30 | 2010-11-24 | Ｊｆｅスチール株式会社 | Manufacturing method of high-tensile cold-rolled steel sheet in continuous annealing process |
| CN109321741A (en) * | 2017-07-31 | 2019-02-12 | 湖北华鑫科技股份有限公司 | The automatic annealing machine of precision steel strip |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2807918B2 (en) | 1998-10-08 |
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