JPH05179339A - Skid mark heater and heating method - Google Patents

Skid mark heater and heating method

Info

Publication number
JPH05179339A
JPH05179339A JP96792A JP96792A JPH05179339A JP H05179339 A JPH05179339 A JP H05179339A JP 96792 A JP96792 A JP 96792A JP 96792 A JP96792 A JP 96792A JP H05179339 A JPH05179339 A JP H05179339A
Authority
JP
Japan
Prior art keywords
heating
combustion
skid
skid mark
furnace
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
Application number
JP96792A
Other languages
Japanese (ja)
Inventor
Mitsuhiro Yamamoto
光博 山本
Motofumi Kaminaka
基文 上仲
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Corp
Original Assignee
Sumitomo Metal Industries Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sumitomo Metal Industries Ltd filed Critical Sumitomo Metal Industries Ltd
Priority to JP96792A priority Critical patent/JPH05179339A/en
Publication of JPH05179339A publication Critical patent/JPH05179339A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To provide the skid mark heater which can efficiently annihilate the skid marks generated at the time of heating slabs in a heating furnace without being affected by the fluctuation in the operation of the heating furnace and has a long life and the heating method which utilizes this heater. CONSTITUTION:This skid mark heater 1 has a combustion device 2 which generates a combustion gas for heating and a conduit 3 consisting of an inside pipe 3a for introducing the combustion gas to the inside of the furnace and an outside pipe 3b for introducing air for cooling likewise into the furnace and is further connected to a computer 6 which controls respective flow rate control valves 2c, 4c, 5c mounted to the combustion device 2 and the conduit 3 by calculating the temp. in the max. temp. part and min. temp. part of the materials to be heated (slabs S) and computing the fuel flow rate and air flow rate for combustion to minimize the temp. difference between both. The heating by this device is executed. The skid marks are further effectively eliminated if this device is installed in correspondence to the plural skids.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】この発明は、加熱炉において鋼材
を加熱する際に生じるスキッドマークを解消するスキッ
ドマーク加熱装置および加熱方法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skid mark heating device and a heating method for eliminating a skid mark generated when a steel material is heated in a heating furnace.

【0002】[0002]

【従来の技術】スラブやブルーム或いはビレットなどの
鋼片は、圧延の前に所定温度まで加熱される。従来、上
記鋼片の加熱にはプッシャー式加熱炉が用いられてい
た。しかし、上記加熱炉ではスキッドマークの発生が著
しく、解消が難しい。そこで最近ではスキッドマークの
発生の少ないウォーキングビーム式加熱炉が用いられて
いる。ウォーキングビーム式加熱炉は、図5(a) (加熱
炉の鋼片抽出側付近の縦断面図)及び図5(b) (図5
(a) のA−A矢視図)に示すような炉であり、炉体21、
固定サポート22及び23、可動サポート24などから構成さ
れている。この加熱炉により鋼片Sを加熱する場合、鋼
片Sは固定サポート22による支持と、可動サポート24の
上昇→前進→下降→後退のサイクル運動により、白抜き
矢印方向に送られつつ所定温度まで加熱される。ところ
が固定サポート22は冷却水により冷却されているため
に、それに支持されているaの位置(図5(b) 参照)が
他の部分より冷却されてスキッドマークが発生する。そ
れを解消するため1サイクル移動後には別の固定サポー
ト23によりbの位置を支持するようにしているが、そう
すると今度はbの位置に新たなスキッドマークが発生す
る。このようにウォーキングビーム式加熱炉でもスキッ
ドマークを完全に消失させることはできない。
Steel pieces such as slabs, blooms and billets are heated to a predetermined temperature before rolling. Conventionally, a pusher-type heating furnace has been used for heating the steel bill. However, in the above heating furnace, the generation of skid marks is remarkable and it is difficult to eliminate them. Therefore, recently, a walking beam type heating furnace with less generation of skid marks is used. The walking beam type heating furnace is shown in Fig. 5 (a) (vertical cross-sectional view near the steel slab extraction side of the heating furnace) and Fig. 5 (b) (Fig. 5).
(a) A-A arrow view) is a furnace as shown in FIG.
It is composed of fixed supports 22 and 23, a movable support 24, and the like. When the steel slab S is heated by this heating furnace, the steel slab S is supported by the fixed support 22 and the movable support 24 is cycled up, forward, down, and backward to reach a predetermined temperature while being sent in the direction of the white arrow. Be heated. However, since the fixed support 22 is cooled by the cooling water, the position a supported by the fixed support 22 (see FIG. 5 (b)) is cooled more than other portions, and skid marks are generated. In order to eliminate this, another fixed support 23 is used to support the position of b after one cycle of movement, but this time, a new skid mark is generated at the position of b. In this way, the walking beam type heating furnace cannot completely eliminate the skid mark.

【0003】そこで本発明者らは図6に示すようなスキ
ッドマーク低減装置11を提案した(実開昭61−198259号
公報、実開昭62− 75060号公報)。このスキッドマーク
低減装置11は加熱炉の鋼片抽出側に設けられ、スキッド
マークを加熱する燃焼ガスを発生させる燃焼装置12と、
燃焼ガスを加熱炉内に導く金属又はセラミックスで造ら
れた導管13から構成されている。この装置11によりスキ
ッドマークを加熱するには、燃焼装置12で発生した燃焼
ガスを導管13を介してスキッドマークに吹きつけ、低温
部を加熱して消失させる。しかしこの装置には導管の寿
命が著しく短いという欠点がある。導管は炉内雰囲気温
度が1200〜1300℃にも達する鋼片抽出側に設置され、ま
たその内側には1200℃以上の燃焼ガスが流される。導管
が金属製の場合には強度が低下して自重により変形した
り、閉塞したりする。一方、それがセラミックス製の場
合には鋼片を炉から搬出するとき侵入する空気によって
急冷され、ヒートショックを起こして破壊することがあ
る。そのために導管の寿命は金属製のもので約6ヶ月、
セラミックス製のもので2〜3ヶ月程度である。
Therefore, the present inventors have proposed a skid mark reduction device 11 as shown in FIG. 6 (Japanese Utility Model Publication No. 61-198259 and Japanese Utility Model Publication No. 62-75060). This skid mark reduction device 11 is provided on the billet extraction side of the heating furnace, and a combustion device 12 that generates combustion gas that heats the skid mark,
It is composed of a conduit 13 made of metal or ceramics that guides combustion gas into the heating furnace. In order to heat the skid mark by this device 11, the combustion gas generated in the combustion device 12 is blown to the skid mark via the conduit 13 to heat and extinguish the low temperature part. However, this device has the disadvantage that the life of the conduit is extremely short. The conduit is installed on the steel slab extraction side where the furnace atmosphere temperature reaches 1200 to 1300 ℃, and the combustion gas of 1200 ℃ or higher is flown inside. When the conduit is made of metal, its strength decreases and it is deformed or blocked by its own weight. On the other hand, if it is made of ceramics, it may be rapidly cooled by the air that enters when the steel strip is carried out of the furnace, causing a heat shock and breaking. Therefore, the life of the conduit is about 6 months if it is made of metal,
It is made of ceramics and takes about 2 to 3 months.

【0004】本発明者らは更に検討を重ね、図7に示す
ような、スキッドマークを効率よく消失でき、しかも長
い寿命を有するスキッドマーク加熱装置を考案した(特
開平3−111513号公報)。このスキッドマーク加熱装置
は耐熱鋼で作られた内管3aと外管3bからなる2重管構造
の導管3を有し、内管3aの一端に取り付けられた燃焼装
置2により燃料を燃焼させて燃焼ガスを加熱炉内に導く
のであるが、燃焼の際、燃焼用空気は理論空燃比より少
なくし、発生した不完全燃焼排ガスは内管3a内を通過さ
せ、外管3b内には冷却用空気を流す。冷却用空気は二重
管を十分冷却しながら二重管出口で不完全燃焼排ガスと
混合され、二次燃焼して被加熱材の低温部を加熱してス
キッドマークを消失させる。
The inventors of the present invention have made further studies and have devised a skid mark heating device as shown in FIG. 7 which can efficiently eliminate skid marks and has a long life (JP-A-3-111513). This skid mark heating device has a double-pipe structure conduit 3 composed of an inner pipe 3a and an outer pipe 3b made of heat-resistant steel, and burns fuel by a combustion device 2 attached to one end of the inner pipe 3a. The combustion gas is guided into the heating furnace, but during combustion, the combustion air is made less than the stoichiometric air-fuel ratio, the generated incomplete combustion exhaust gas is passed through the inner pipe 3a, and the outer pipe 3b is cooled. Let the air flow. The cooling air is sufficiently mixed with the incompletely combusted exhaust gas at the outlet of the double pipe while sufficiently cooling the double pipe, and secondarily burns to heat the low temperature portion of the material to be heated to eliminate the skid mark.

【0005】しかし、この装置では被加熱材の抽出ピッ
チが大きく変動するような加熱炉に適用する場合、期待
するスキッドマーク解消効果が得られないことがある。
特に、複数の加熱炉のうち1〜2炉を連続鋳造機と連結
させ、連続鋳造材の加熱に使用する場合は、この連続鋳
造機に直結させた炉を優先して操業することになるの
で、この炉以外の炉の抽出ピッチは3〜60分程度の範囲
で大きく変動する。そのため、スキッドマーク加熱装置
1による被加熱材の加熱時間が同様に変動し、スキッド
マークが発生している低温部の温度にバラツキが生じ、
あるいは逆に加熱時間が長すぎる場合は加熱部が局部的
に高温になったりするおそれがある。
However, when this apparatus is applied to a heating furnace in which the extraction pitch of the material to be heated varies greatly, the desired skid mark elimination effect may not be obtained.
In particular, when 1 to 2 furnaces among a plurality of heating furnaces are connected to a continuous casting machine and used for heating a continuous casting material, the furnace directly connected to the continuous casting machine is preferentially operated. The extraction pitch of furnaces other than this furnace fluctuates greatly within the range of about 3 to 60 minutes. Therefore, the heating time of the material to be heated by the skid mark heating device 1 also fluctuates in the same manner, and the temperature of the low temperature part where the skid mark is generated varies,
On the contrary, if the heating time is too long, the heating part may locally have a high temperature.

【0006】[0006]

【発明が解決しようとする課題】本発明の目的は、加熱
炉で鋼片を加熱するときに発生するスキッドマークを加
熱炉の操業変動に影響されることなく効率よく消失で
き、しかも長い寿命を有するスキッドマーク加熱装置と
それを利用する加熱方法を提供することにある。
DISCLOSURE OF THE INVENTION An object of the present invention is to efficiently eliminate skid marks generated when a steel slab is heated in a heating furnace without being affected by fluctuations in the operation of the heating furnace, and to provide a long service life. An object of the present invention is to provide a skid mark heating device and a heating method using the same.

【0007】[0007]

【課題を解決するための手段】本発明者らは、どのよう
な加熱状況下でもスキッドマーク量(後述)を最小にす
ることができる方法について検討を重ねた結果、被加熱
材のスキッドマーク量をコンピュータを利用して予測
し、その程度に応じてスキッドマーク加熱装置の燃焼量
を変化させる加熱装置および加熱方法を発明した。本発
明の要旨は下記のスキッドマーク加熱装置および下記
の加熱方法にある。
The inventors of the present invention have made extensive studies on a method capable of minimizing the skid mark amount (described later) under any heating condition, and as a result, the skid mark amount of the material to be heated is obtained. Inventing a heating device and a heating method for predicting the temperature using a computer and changing the combustion amount of the skid mark heating device according to the degree. The gist of the present invention resides in the following skid mark heating device and the following heating method.

【0008】 加熱炉の鋼片抽出側に設けられ、被加
熱材のスキッドマークを加熱する装置であって、この装
置は加熱用燃焼ガスを発生させる燃焼装置と、燃焼ガス
を炉内に導く内管および冷却用空気を同じく炉内に導く
外管からなる導管を備え、更に、コンピュータに接続さ
れている。このコンピュータは被加熱材の最高温度部分
と最低温度部分の温度を算出し、両者の温度差を最小に
する燃料流量および燃焼用空気流量を演算し、その信号
を燃焼装置の燃料供給用配管と燃焼用空気配管、および
導管の外管に取り付けられている冷却用空気配管の各流
量制御弁に出力してこれらの各流量制御弁を制御する。
A device for heating a skid mark of a material to be heated, which is provided on the steel slab extraction side of the heating furnace, and includes a combustion device for generating combustion gas for heating and an internal device for introducing the combustion gas into the furnace. It is provided with a conduit consisting of a tube and an outer tube which also guides the cooling air into the furnace and is further connected to a computer. This computer calculates the temperature of the highest temperature part and the lowest temperature part of the material to be heated, calculates the fuel flow rate and combustion air flow rate that minimize the temperature difference between the two, and outputs the signal to the fuel supply pipe of the combustion device. It outputs to each flow control valve of the combustion air piping and the cooling air piping attached to the outer pipe of the conduit to control each of these flow control valves.

【0009】 上記のスキッドマーク加熱装置によ
る加熱方法であって、コンピュータの出力信号に基づい
て、燃焼装置により不完全燃焼させたガスを内管から排
出させ、外管から空気を供給して導管外で二次燃焼させ
ることを特徴とするスキッドマーク加熱方法。
In the heating method using the skid mark heating device, the gas that has been incompletely burned by the combustion device is discharged from the inner pipe based on the output signal of the computer, and air is supplied from the outer pipe to outside the conduit. The skid mark heating method is characterized in that the secondary combustion is performed with.

【0010】[0010]

【作用】以下、本発明のスキッドマーク加熱装置および
加熱方法を図面を用いて説明する。
The skid mark heating device and heating method of the present invention will be described below with reference to the drawings.

【0011】図1は本発明の加熱装置の一例を設置した
加熱炉の鋼片抽出側付近の縦断面図である。この図にお
いて、1が本発明のスキッドマーク加熱装置であり、21
は炉体、23は固定サポート、24は可動サポート、25は開
閉扉、Sは鋼片である。加熱装置1は燃焼装置2と導管
3から構成され、燃焼装置2はバーナ2a、燃料供給用配
管2bおよび燃焼用空気配管4bを備えている。導管3は耐
熱性金属またはセラミックスなどの材料から作られる。
そして、その構造は図7のものと同じように内管3aと外
管3bからなり、その炉内側端部には燃焼ガスと冷却用空
気の排出口3cを、燃焼装置2側には冷却用空気配管5bを
備えている。各配管2b、4b、5bにはそれぞれ流量制御弁
2c、4c、5cおよび流量計2d、4d、5dが設置され、燃料供
給用配管2bにはさらに燃料遮断弁2eが設置されている。
前記排出口3cの外管出口に空気と燃焼ガスとの混合をよ
くする旋回羽根3eを設けてもよい。
FIG. 1 is a vertical cross-sectional view of the vicinity of a billet extraction side of a heating furnace in which an example of the heating device of the present invention is installed. In this figure, 1 is a skid mark heating device of the present invention,
Is a furnace body, 23 is a fixed support, 24 is a movable support, 25 is an opening / closing door, and S is a billet. The heating device 1 includes a combustion device 2 and a conduit 3. The combustion device 2 includes a burner 2a, a fuel supply pipe 2b, and a combustion air pipe 4b. The conduit 3 is made of a material such as refractory metal or ceramics.
The structure is made up of an inner pipe 3a and an outer pipe 3b as in the case of FIG. 7, a combustion gas and cooling air discharge port 3c is provided at the inner end of the furnace, and a combustion device 2 side is provided for cooling. It is equipped with an air pipe 5b. Flow control valves are installed on each pipe 2b, 4b, 5b.
2c, 4c, 5c and flow meters 2d, 4d, 5d are installed, and a fuel cutoff valve 2e is further installed in the fuel supply pipe 2b.
A swirl vane 3e for improving mixing of air and combustion gas may be provided at the outer pipe outlet of the discharge port 3c.

【0012】この加熱装置1は炉内に設けられた支持柱
4のような支持手段により支えられている。なお、この
図の加熱装置1は鋼片Sの搬出装置(図示省略)との設
備的制約のために傾斜して設置されているが、このよう
な形式に限定されるものではない。
The heating device 1 is supported by a supporting means such as a supporting column 4 provided in the furnace. The heating device 1 in this figure is installed so as to be inclined with respect to the equipment for discharging the steel slab S (not shown), but is not limited to this type.

【0013】6はコンピュータで、各配管の流量制御弁
2c、4cおよび5cと接続されており、材料の形状、材質に
関する情報や、炉温、トラッキング情報を入力して、後
述するように、鋼片Sの最高温度部分と最低温度部分
(スキッドマーク部)の温度および両者の差(以下、こ
れをスキッドマーク量という)を算出する。さらに、こ
のスキッドマーク量を最小にする燃料流量および燃焼用
空気流量を演算し、その出力信号をスキッドマーク加熱
装置1の流量制御弁2c、4cおよび5cへ送る。
A computer 6 is a flow control valve for each pipe.
It is connected to 2c, 4c and 5c, and by inputting information about material shape, material, furnace temperature and tracking information, as described later, the highest temperature part and the lowest temperature part of the steel slab S (skid mark part) ) And the difference between the two (hereinafter referred to as the skid mark amount). Further, the fuel flow rate and the combustion air flow rate that minimize the skid mark amount are calculated, and the output signals are sent to the flow rate control valves 2c, 4c and 5c of the skid mark heating device 1.

【0014】鋼片S(鋼材)の最高温度部分と最低温度
部分の温度の計算は差分法により行う。
The temperature of the highest temperature portion and the lowest temperature portion of the steel slab S (steel material) is calculated by the difference method.

【0015】図2は、鋼材を加熱炉内に装入してからス
キッドマーク加熱装置の取り付け位置の直前までの間に
おける伝熱モデルを説明するための図で、鋼材は固定サ
ポート23のスキッドパイプ26に取り付けられたスキッド
レール27により支えられている。鋼材に与えられる熱は
3(雰囲気からの輻射による伝熱量)、鋼材から失われ
る熱はQ1(スキッドパイプへの熱伝導による伝熱量) 、
2(スキッドパイプへの輻射による伝熱量) およびQ
4(スキッドレールへの輻射による伝熱量) 、スキッドレ
ールに与えられる熱はQ5(雰囲気からの輻射による伝熱
量) である。
FIG. 2 is a view for explaining a heat transfer model from the time when the steel material is loaded into the heating furnace to immediately before the mounting position of the skid mark heating device. The steel material is a skid pipe of the fixed support 23. It is supported by a skid rail 27 attached to 26. The heat given to the steel is Q 3 (heat transfer due to radiation from the atmosphere), the heat lost from the steel is Q 1 (heat transfer due to heat conduction to the skid pipe),
Q 2 (heat transfer due to radiation to skid pipe) and Q
4 (heat transfer amount due to radiation to the skid rail), the heat given to the skid rail is Q 5 (heat transfer amount due to radiation from the atmosphere).

【0016】また、図3はスキッドマーク加熱装置で加
熱を開始してから抽出までの間における伝熱モデルを説
明するための図で、スキッドレールにより支えられてい
た部分にスキッドマーク加熱装置から燃焼ガスが吹き付
けられている状態を示す。鋼材に与えられる熱はQ6(ス
キッドマーク加熱装置の火炎からの輻射による伝熱量)
およびQ8(雰囲気からの輻射による伝熱量)、鋼材から
失われる熱はQ7(雰囲気への輻射による伝熱量) であ
る。
Further, FIG. 3 is a diagram for explaining a heat transfer model from the start of heating by the skid mark heating device to the extraction, in which the portion supported by the skid rail is burned by the skid mark heating device. The state where the gas is sprayed is shown. The heat given to the steel material is Q 6 (the amount of heat transferred by the radiation from the flame of the skid mark heating device)
And Q 8 (heat transfer amount due to radiation from the atmosphere), and the heat lost from the steel material is Q 7 (heat transfer amount due to radiation to the atmosphere).

【0017】境界面の伝熱モデルは以下の通りである。The heat transfer model of the boundary surface is as follows.

【0018】(1)鋼材装入〜スキッドマーク加熱装置
直前まで(図2参照)
(1) From charging of steel material to immediately before the skid mark heating device (see FIG. 2)

【0019】[0019]

【数1】 [Equation 1]

【0020】[0020]

【数2】 [Equation 2]

【0021】[0021]

【数3】 [Equation 3]

【0022】[0022]

【数4】 [Equation 4]

【0023】[0023]

【数5】 [Equation 5]

【0024】(2)スキッドマーク加熱装置〜抽出まで
(図3参照)
(2) From skid mark heating device to extraction (see FIG. 3)

【0025】[0025]

【数6】 [Equation 6]

【0026】[0026]

【数7】 [Equation 7]

【0027】[0027]

【数8】 [Equation 8]

【0028】前記伝熱モデルはある瞬間の各部の熱収支
を表すものであり、分割した区分毎に、その中心点の熱
収支により微小時間経過後の温度変化を繰り返し計算す
る。
The heat transfer model represents the heat balance of each part at a certain moment, and the temperature change after a lapse of a minute time is repeatedly calculated for each divided section by the heat balance of the central point.

【0029】そして、スキッドマーク加熱装置に到達す
る時点の鋼片各部の温度を算出する。
Then, the temperature of each part of the steel slab at the time of reaching the skid mark heating device is calculated.

【0030】この計算結果によると、鋼片の温度は、通
常、スキッドレールの直上部で最も低く、スキッドレー
ル間(鋼片中央部)または鋼片の端部で最も高くなる。
According to the result of this calculation, the temperature of the billet is usually the lowest just above the skid rail and the highest between the skid rails (the center of the billet) or at the end of the billet.

【0031】これらの温度の差からスキッドマーク量を
求め、これを最小にする燃焼量、すなわち、燃焼装置へ
供給する燃料および燃焼用空気の流量を演算し、これを
燃焼装置の燃料供給用配管と燃焼用空気配管、および導
管の外管に取り付けられている冷却用空気配管の各流量
制御弁2c、4c、5c、に出力する。
The skid mark amount is obtained from the difference between these temperatures, the combustion amount that minimizes the skid mark amount, that is, the flow rates of the fuel and the combustion air to be supplied to the combustion device are calculated, and the calculated values are used as the fuel supply pipe for the combustion device. And to the flow control valves 2c, 4c, 5c of the combustion air pipe and the cooling air pipe attached to the outer pipe of the conduit.

【0032】次に、前記の加熱装置により行う本発明の
加熱方法について説明する。
Next, the heating method of the present invention performed by the above heating device will be described.

【0033】本発明方法では、燃焼に必要な空気量は燃
焼用空気配管4bから導入する燃焼用空気と冷却用空気配
管5bから導入する冷却用空気で、それらの合計が空気比
1.05〜1.1 となるように供給する。すなわち、前記図7
に示した装置の場合と同様に、内管3aの一端に取り付け
られた燃焼装置2により燃料を燃焼させて燃焼ガスを加
熱炉内に導くのであるが、燃焼の際、燃焼用空気は理論
空燃比より少なくし、発生した不完全燃焼排ガスは内管
3a内を通過させ、外管3b内には冷却用空気(二次燃焼空
気)を流す。冷却用空気は外管3bと内管3aを冷却しなが
ら排出口3cで前記の不完全燃焼排ガスと混合され、二次
燃焼して鋼片Sの低温部を加熱し、スキッドマークを消
失させる。
In the method of the present invention, the amount of air required for combustion is the combustion air introduced from the combustion air pipe 4b and the cooling air introduced from the cooling air pipe 5b, the sum of which is the air ratio.
Supply it to be 1.05 to 1.1. That is, FIG.
As in the case of the device shown in Fig. 2, the combustion device 2 attached to one end of the inner pipe 3a burns the fuel to introduce the combustion gas into the heating furnace. Incomplete combustion exhaust gas generated by reducing the fuel ratio below the inner pipe
Cooling air (secondary combustion air) is passed through the outer pipe 3b while passing through the inside of 3a. The cooling air is mixed with the incompletely combusted exhaust gas at the discharge port 3c while cooling the outer pipe 3b and the inner pipe 3a, and secondarily burns to heat the low temperature portion of the steel slab S to eliminate the skid mark.

【0034】スキッドマーク加熱装置の加熱時間が長く
なって、燃焼量を絞る場合、冷却用空気の流量は最大負
荷の30%よりも低下しないようにするのがよい。これ
は、二重管構造の導管の冷却を十分に行い、過度の加熱
を防ぐためである。
When the heating time of the skid mark heating device becomes long and the combustion amount is reduced, it is preferable that the flow rate of the cooling air does not fall below 30% of the maximum load. This is to sufficiently cool the double-pipe structure conduit and prevent excessive heating.

【0035】また、加熱時間が60分を超えるような場合
は、燃料遮断弁2eを閉鎖して燃料の送通を遮断する機能
も付与する方がよい。
Further, when the heating time exceeds 60 minutes, it is better to add the function of closing the fuel cutoff valve 2e to cut off the fuel flow.

【0036】なお、スキッドによっては、スキッドパイ
プに流れる冷却水量に差があったり、スキッドの温度が
異なったりするので、スキッドマーク加熱装置を各固定
スキッドに設置し、各スキッド毎にスキッドマーク量を
計算して、それぞれのスキッドマーク量に応じて個別に
燃料および燃焼用空気の流量を設定すれば、スキッドマ
ークを効果的に解消することができる。
Depending on the skid, the amount of cooling water flowing through the skid pipe may differ and the temperature of the skid may differ. Therefore, a skid mark heating device is installed on each fixed skid, and the skid mark amount is set for each skid. The skid mark can be effectively eliminated by calculating and individually setting the flow rates of the fuel and the combustion air according to the respective skid mark amounts.

【0037】加熱炉内の鋼片は、通常、加熱炉の出側に
最も近い位置(抽出待機位置)で次の抽出までの間(普
通は6分間以上)保持されるので、この間でスキッドマ
ーク加熱装置により上記のように算出される温度差、即
ち、スキッドマーク量を解消するための加熱を行う。加
熱は、鋼片が比較的短い時間、抽出待機位置で保持され
た後抽出される場合に備えて、最初は 100%能力でバー
ナ加熱を行って、例えば、目標温度より5℃程度低い下
限温度まで昇熱し、その後は上限温度(通常、目標温度
+5℃)および下限温度(通常、目標温度−5℃)の範
囲内に納まるように30〜80%能力で加熱する。もし、上
限を超えるようであれば消火する。なお、抽出までの時
間がわかっている場合は、前記の伝熱モデルを用いて算
出される最適加熱パターンで加熱することも可能であ
る。
The steel slab in the heating furnace is usually held at the position closest to the outlet side of the heating furnace (extraction standby position) until the next extraction (usually 6 minutes or more). The heating device performs heating for eliminating the temperature difference calculated as described above, that is, the skid mark amount. Heating is performed by burner heating with 100% capacity at the beginning, in case the steel slab is held in the extraction standby position for a relatively short time and then extracted. For example, the lower limit temperature is about 5 ° C lower than the target temperature. After that, the temperature is increased to 30% to 80% so as to be within the range of the upper limit temperature (usually target temperature + 5 ° C) and the lower limit temperature (usually target temperature -5 ° C). If it exceeds the upper limit, extinguish the fire. In addition, when the time until extraction is known, it is also possible to perform heating with the optimum heating pattern calculated using the heat transfer model.

【0038】[0038]

【実施例】図1に示すようなスキッドマーク加熱装置を
加熱能力 300トン/hのウォーキングビーム式熱延加熱
炉に設置し、その寿命とスキッドマークの解消状態を調
べた。導管3の内管3aの直径は36mm、外管3bの直径は53
mmであり、外管3bの外周には厚さ50mmのセラミックス繊
維の断熱材が巻かれている。その材料は20%Ni−25%Cr
鋼の耐熱鋼である。燃料にはコークス炉ガスを用い、そ
れを流量33Nm3/h で燃焼装置2に供給して空燃比 0.8で
燃焼させ、導管出口で空燃比1.05となるように外管3bか
ら冷却用空気(二次燃焼空気)を供給した。また、スキ
ッドマーク加熱装置の操作においては、燃料供給用配管
2b、燃焼用空気配管4bおよび冷却用空気配管5bの各流量
制御弁2c、4cおよび5cと接続されたコンピュータの出力
信号に基づいて直接計算機制御(DDC制御)を行っ
た。
EXAMPLE A skid mark heating apparatus as shown in FIG. 1 was installed in a walking beam type hot rolling heating furnace having a heating capacity of 300 tons / h, and its life and the state of eliminating skid marks were examined. The inner tube 3a of the conduit 3 has a diameter of 36 mm, and the outer tube 3b has a diameter of 53
The outer tube 3b is wound around the outer tube 3b with a ceramic fiber heat insulating material having a thickness of 50 mm. The material is 20% Ni-25% Cr
It is a heat-resistant steel. Coke oven gas was used as the fuel, and it was supplied to the combustor 2 at a flow rate of 33 Nm 3 / h and burned at an air-fuel ratio of 0.8, and the cooling air (2 Next combustion air) was supplied. In addition, when operating the skid mark heating device,
Direct computer control (DDC control) was performed based on the output signals of the computers connected to the flow rate control valves 2c, 4c and 5c of 2b, the combustion air pipe 4b and the cooling air pipe 5b.

【0039】上記の条件で約6ヶ月テストを実施した結
果、装置に何らトラブルもなく、スキッドマークを大幅
に低減することができた。
As a result of carrying out the test for about 6 months under the above-mentioned conditions, there was no trouble in the apparatus and skid marks could be greatly reduced.

【0040】図4は加熱炉から抽出し熱間粗圧延機で圧
延した直後の鋼板上面中央部の温度を長手方向に連続測
定した結果の代表例であり、(a) はスキッドマーク加熱
装置のない従来の加熱炉で加熱した場合、(b) は本発明
方法によりスキッドマーク加熱を行った場合である。ス
キッドマーク加熱を行った場合、鋼片の長さ方向におけ
る温度の変化が著しく減少している。
FIG. 4 is a representative example of the results of continuous measurement of the temperature of the central portion of the upper surface of the steel sheet immediately after being extracted from the heating furnace and rolled by the hot rough rolling mill, in which (a) is the skid mark heating apparatus. When heated in a conventional heating furnace not shown, (b) is a case where skid mark heating is performed by the method of the present invention. When skid mark heating is performed, the change in temperature in the length direction of the billet is significantly reduced.

【0041】また、スラブ 200本を対象として、上記の
加熱装置を用い本発明方法でスキッドマーク加熱を行っ
た場合とスキッドマーク部加熱量の制御を行わずに80%
能力(一定)でバーナー加熱を行った場合とで比較試験
を行い、粗圧延後の鋼片内の温度差(最高温度部分と最
低温度部分の温度差)を測定した。本発明方法では、抽
出目標温度が1150〜1160℃の範囲にあるスラブに対し
て、それぞれ、加熱量制御の上限および下限温度は±5
℃、抽出目標温度は、最高温度の代表点として鋼片中央
部上面点の温度を採り、その温度に対して−3℃で設定
した。
Further, for 200 slabs, when the skid mark heating is performed by the method of the present invention using the above heating device and when the skid mark portion heating amount is not controlled to 80%.
A comparative test was performed with the case where burner heating was performed with a constant capacity (constant), and the temperature difference (temperature difference between the highest temperature portion and the lowest temperature portion) in the steel slab after rough rolling was measured. In the method of the present invention, the upper and lower limits of the heating amount control are ± 5 for the slabs whose extraction target temperature is in the range of 1150 to 1160 ° C, respectively.
C. and the extraction target temperature were set at -3.degree. C. with respect to the temperature of the upper surface point of the central portion of the steel slab as a representative point of the maximum temperature.

【0042】試験の結果、表1に示すように、本発明方
法を適用した場合は待機時間の長短に関係なく鋼片内の
温度差が小さかった。
As a result of the test, as shown in Table 1, when the method of the present invention was applied, the temperature difference in the steel slab was small regardless of the length of the waiting time.

【0043】[0043]

【表1】 [Table 1]

【0044】[0044]

【発明の効果】本発明のスキッドマーク加熱装置および
加熱方法によれば、加熱炉の操業変動に影響されること
なく、被加熱材のスキッドマークを効率よく消失するこ
とができる。また、長期間の使用にも十分耐え得る。
According to the skid mark heating device and the heating method of the present invention, the skid mark on the material to be heated can be efficiently eliminated without being affected by the fluctuation in the operation of the heating furnace. Further, it can withstand long-term use sufficiently.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明のスキッドマーク加熱装置の一例の構成
を示す図である。
FIG. 1 is a diagram showing a configuration of an example of a skid mark heating device of the present invention.

【図2】鋼材装入からスキッドマーク加熱装置直前まで
の間における伝熱モデルを説明するための図である。
FIG. 2 is a diagram for explaining a heat transfer model from a steel material charging to immediately before a skid mark heating device.

【図3】スキッドマーク加熱装置から抽出までの間にお
ける伝熱モデルを説明するための図である。
FIG. 3 is a diagram for explaining a heat transfer model from a skid mark heating device to extraction.

【図4】粗圧延機出口における鋼板の温度を示す図で、
(a) 図はスキッドマーク加熱を行わない場合、(b) 図は
本発明方法によるスキッドマーク加熱を行った場合であ
る。
FIG. 4 is a diagram showing the temperature of the steel sheet at the exit of the rough rolling mill,
(a) is the case where the skid mark heating is not performed, and (b) is the case where the skid mark heating is performed by the method of the present invention.

【図5】ウォーキングビーム式加熱炉の図で、(a) 図は
鋼片抽出側付近の縦断面図、(b) 図は(a) 図のA−A矢
視図である。
FIG. 5 is a view of a walking beam heating furnace, in which (a) is a vertical cross-sectional view in the vicinity of the billet extraction side, and (b) is a view taken along the line AA of (a).

【図6】従来のスキッドマーク低減装置の図である。FIG. 6 is a view of a conventional skid mark reduction device.

【図7】従来のスキッドマーク加熱装置の図である。FIG. 7 is a diagram of a conventional skid mark heating device.

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】加熱炉の鋼片抽出側に設けられ、被加熱材
のスキッドマークを加熱する装置であって、前記装置は
加熱用燃焼ガスを発生させる燃焼装置と、燃焼ガスを炉
内に導く内管および冷却用空気を同じく炉内に導く外管
からなる導管を備え、更に、被加熱材の最高温度部分と
最低温度部分の温度を算出し、両者の温度差を最小にす
る燃料流量および燃焼用空気流量を演算し、その信号を
燃焼装置の燃料供給用配管と燃焼用空気配管、および導
管の外管に取り付けられている冷却用空気配管の各流量
制御弁に出力してこれらの各流量制御弁を制御するコン
ピュータと接続されていることを特徴とするスキッドマ
ーク加熱装置。
1. A device for heating a skid mark of a material to be heated, which is provided on a steel slab extraction side of a heating furnace, said device comprising a combustion device for generating combustion gas for heating, and the combustion gas in the furnace. A fuel flow that minimizes the temperature difference between the highest temperature part and the lowest temperature part of the material to be heated by providing a conduit consisting of an inner tube for guiding and an outer tube for guiding cooling air to the furnace And the combustion air flow rate is calculated, and the signal is output to the fuel supply pipe of the combustion device and the combustion air pipe, and is output to each flow control valve of the cooling air pipe attached to the outer pipe of the conduit to output these signals. A skid mark heating device, which is connected to a computer that controls each flow control valve.
【請求項2】請求項1記載のスキッドマーク加熱装置に
よる加熱方法であって、コンピュータの出力信号に基づ
いて、燃焼装置により不完全燃焼させたガスを内管から
排出させ、外管から空気を供給して導管外で二次燃焼さ
せることを特徴とするスキッドマーク加熱方法。
2. The heating method by the skid mark heating device according to claim 1, wherein the gas incompletely burned by the combustion device is discharged from the inner pipe and the air is discharged from the outer pipe based on the output signal of the computer. A method for heating skid marks, which comprises supplying and performing secondary combustion outside the conduit.
JP96792A 1992-01-07 1992-01-07 Skid mark heater and heating method Pending JPH05179339A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP96792A JPH05179339A (en) 1992-01-07 1992-01-07 Skid mark heater and heating method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP96792A JPH05179339A (en) 1992-01-07 1992-01-07 Skid mark heater and heating method

Publications (1)

Publication Number Publication Date
JPH05179339A true JPH05179339A (en) 1993-07-20

Family

ID=11488404

Family Applications (1)

Application Number Title Priority Date Filing Date
JP96792A Pending JPH05179339A (en) 1992-01-07 1992-01-07 Skid mark heater and heating method

Country Status (1)

Country Link
JP (1) JPH05179339A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6945776B2 (en) 2002-07-25 2005-09-20 Posco Method and a skid member for reducing temperature difference in a heating subject and a skid apparatus using them

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS533912B2 (en) * 1973-08-16 1978-02-10
JPS5672119A (en) * 1979-11-20 1981-06-16 Ishikawajima Harima Heavy Ind Co Ltd Temperature compensation method of steel product and its apparatus
JPS5829168U (en) * 1981-08-21 1983-02-25 株式会社日立製作所 internal combustion engine ignition system
JPS61170508A (en) * 1985-01-25 1986-08-01 Sumitomo Metal Ind Ltd Method for erasing skid mark in continuous heating furnace
JPH03111513A (en) * 1989-09-26 1991-05-13 Sumikin Manejimento Kk Device and method for heating under eliminating skid mark

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS533912B2 (en) * 1973-08-16 1978-02-10
JPS5672119A (en) * 1979-11-20 1981-06-16 Ishikawajima Harima Heavy Ind Co Ltd Temperature compensation method of steel product and its apparatus
JPS5829168U (en) * 1981-08-21 1983-02-25 株式会社日立製作所 internal combustion engine ignition system
JPS61170508A (en) * 1985-01-25 1986-08-01 Sumitomo Metal Ind Ltd Method for erasing skid mark in continuous heating furnace
JPH03111513A (en) * 1989-09-26 1991-05-13 Sumikin Manejimento Kk Device and method for heating under eliminating skid mark

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6945776B2 (en) 2002-07-25 2005-09-20 Posco Method and a skid member for reducing temperature difference in a heating subject and a skid apparatus using them

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