TWI413554B - Furnace pressure control method - Google Patents
Furnace pressure control method Download PDFInfo
- Publication number
- TWI413554B TWI413554B TW100100010A TW100100010A TWI413554B TW I413554 B TWI413554 B TW I413554B TW 100100010 A TW100100010 A TW 100100010A TW 100100010 A TW100100010 A TW 100100010A TW I413554 B TWI413554 B TW I413554B
- Authority
- TW
- Taiwan
- Prior art keywords
- furnace
- furnace pressure
- pressure control
- discharge
- door
- Prior art date
Links
Landscapes
- Furnace Details (AREA)
Abstract
Description
本發明係關於一種壓力控制方法，特別是一種爐壓控制方法。The present invention relates to a pressure control method, and more particularly to a furnace pressure control method.
在習知熱軋如熱軋鋼帶產線中，鋼胚需經加熱爐加熱升溫至1000度以上，以便進行後續軋延製程。習知熱軋產線中，鋼胚需由進料側送入加熱爐內，經預熱區、加熱區與均熱區等分段升溫過程達目標溫度，再由出料側將高溫鋼胚抽出，放置於出料輥輪進行出料。因此，出料爐門需時常開啟關閉以抽取鋼胚，出料爐門開啟時有可能發生加熱爐內高溫氣體冒出，或爐外冷空氣大量吸入爐內等現象，所以一習知加熱爐都會設置爐壓控制系統。In the conventional hot rolling such as hot rolled steel strip production line, the steel embryo needs to be heated by a heating furnace to a temperature of 1000 degrees or more for subsequent rolling process. In the conventional hot rolling production line, the steel embryo needs to be fed into the heating furnace from the feeding side, and the temperature is raised to the target temperature through the preheating zone, the heating zone and the soaking zone, and then the high temperature steel embryo is discharged from the discharge side. It is taken out and placed on the discharge roller for discharging. Therefore, the discharge furnace door needs to be opened and closed frequently to extract the steel blank. When the discharge furnace door is opened, there may be a phenomenon that the high temperature gas in the heating furnace is emitted, or the cold air outside the furnace is greatly sucked into the furnace, so that a conventional heating furnace is used. The furnace pressure control system will be set up.
要強調的是，加熱爐內之壓力並非均勻，因加熱爐內之燃燒器所產生廢氣之氣流，以及燃燒器之位置分佈，讓爐壓會沿爐長方向遞增，且整個三維空間壓力場與爐內氣體流場相關，無法完全控制出料爐門附近壓力場分佈，故在習知技術中僅在靠近出料爐門附近之側面爐壁裝設爐壓感測器，經由爐壓感測器量測爐壓，並藉由調整廢氣調節閥開度以改變煙道廢氣流量，進而控制加熱爐之爐壓。It should be emphasized that the pressure in the heating furnace is not uniform. The flow of the exhaust gas generated by the burner in the heating furnace and the position distribution of the burner cause the furnace pressure to increase along the length of the furnace, and the pressure field of the entire three-dimensional space is The gas flow field in the furnace is related, and the pressure field distribution near the discharge furnace door cannot be completely controlled. Therefore, in the prior art, the furnace pressure sensor is installed only on the side wall near the discharge furnace door, and the furnace pressure is sensed. The furnace pressure is measured, and the furnace exhaust pressure is controlled by adjusting the opening of the exhaust gas regulating valve to change the flue gas flow rate.
在出料爐門側，加熱爐內高溫氣體與爐外大氣之垂直靜壓差，以及流場效應，導致出料爐門開啟時爐內高溫氣體外流，同時外面冷空氣由爐門底部吸入爐內。此時，提高爐壓雖可減少爐外空氣吸入，但爐壓過高可能導致爐火外冒、熱氣外溢造成能源浪費及環境高溫等問題。On the side of the discharge furnace door, the vertical static pressure difference between the high temperature gas in the heating furnace and the atmosphere outside the furnace, and the flow field effect, cause the high temperature gas in the furnace to open when the discharge furnace door is opened, and the outside cold air is sucked into the furnace from the bottom of the furnace door. Inside. At this time, although increasing the furnace pressure can reduce the inhalation of air outside the furnace, the excessively high furnace pressure may cause problems such as the escape of the fire, the overflow of the hot gas, the waste of energy, and the high temperature of the environment.
另一方面，若爐壓過低將導致爐門開啟時，大量空氣吸入爐內，造成出料過程鋼胚兩測溫降速率不同而形成寬度方向溫差，同時影響爐內溫度梯度，劣化爐溫均溫能力，造成熱軋製程穩定性問題。另外，過量冷空氣吸入也會增加能耗，並因增加爐氛氧濃度而加劇鋼胚銹皮增生，以及NOx生成。On the other hand, if the furnace pressure is too low, a large amount of air will be sucked into the furnace when the furnace door is opened, which causes the temperature drop rate of the steel embryo to be different during the discharge process, and the temperature difference in the width direction is formed, which affects the temperature gradient in the furnace and deteriorates the furnace temperature. The uniform temperature capability causes problems in the stability of the hot rolling process. In addition, excessive cold air inhalation will also increase energy consumption, and increase the steel rust scale and NOx formation by increasing the furnace oxygen concentration.
因此，適當調控出料爐壓，讓空氣對流維持在最適平衡點，在不導致爐門過度冒火之前提下，儘可能抑制爐外空氣吸入。依加熱爐操作狀況與爐壓測點位置不同，習知技術中係將加熱爐都控制在0~1.2 mm H2 O範圍內之微正壓狀態。Therefore, the pressure of the discharge furnace is properly regulated to maintain the air convection at an optimum balance point, and it is lifted before the furnace door is excessively fired, and the air inhalation outside the furnace is suppressed as much as possible. Depending on the operating conditions of the furnace and the position of the furnace pressure measuring point, in the prior art, the heating furnace is controlled to a micro-positive pressure state in the range of 0 to 1.2 mm H 2 O.
一般而言，可依加熱爐長期操作結果，找出其最適爐壓設定，但即使爐壓設定值固定，每次出料爐門開啟所吸入之空氣量可能都不一樣。目前並無方法直接量測加熱爐於出料爐門開啟期間之空氣吸入量。In general, the optimum furnace pressure setting can be found based on the long-term operation of the furnace, but even if the furnace pressure setting is fixed, the amount of air sucked in each time the furnace door is opened may be different. There is currently no way to directly measure the amount of air intake by the furnace during the opening of the discharge door.
由於影響空氣吸入量之因素很多，包含可能與爐內空間流場變化及溫度場變化相關，習知技術無法由理論推導或實驗數據歸納分析，求得空氣吸入量之關係，另一方面也沒有方法可以直接即時量測空氣吸入量。Because there are many factors affecting the amount of air inhalation, including the possibility of changes in the flow field and temperature field in the furnace, the conventional techniques cannot be theoretically derived or analyzed by the experimental data to obtain the relationship between the air intake and the other. The method can directly measure the air intake amount directly.
在習知技術中，間接求得空氣吸入量之方法皆須待出料爐門開啟後一段較長時間才能得之，其並無法針對每次出料爐門開啟之空氣吸入量，進行即時控制。In the prior art, the method of indirectly obtaining the air intake amount is required to be obtained after the opening of the discharge furnace door for a long time, and it is impossible to control the air intake amount of each discharge furnace door for immediate control. .
因此，有必要提供一創新且具進步性的爐壓控制方法，以解決上述問題。Therefore, it is necessary to provide an innovative and progressive furnace pressure control method to solve the above problems.
本發明係提供一種爐壓控制方法，包括以下步驟：The invention provides a furnace pressure control method, comprising the following steps:
(a) 獲得一出料爐門複數次開啟時間內之製程數據，每一次之製程數據包含一溫降指標、一爐壓控制誤差平均值及一爐壓控制輸出值變化量，該溫降指標係為該出料爐門開啟時間內之溫降梯度，該爐壓控制誤差平均值係為該出料爐門開啟時間內之爐壓設定值與爐壓量測值的差值之平均值，該爐壓控制輸出值變化量係為一廢氣調節閥門在該出料爐門開啟後一設定時間內之開度變化量；(a) Obtaining process data for a plurality of opening times of a discharge furnace door, and each process data includes a temperature drop index, an average value of a furnace pressure control error, and a change amount of a furnace pressure control output value, the temperature drop indicator The temperature gradient of the opening time of the discharge furnace door is an average value of the difference between the furnace pressure setting value and the furnace pressure measurement value during the opening time of the discharge furnace door. The furnace pressure control output value change amount is an opening change amount of an exhaust gas regulating valve within a set time after the discharge furnace door is opened;
(b) 依據該等溫降指標及該等爐壓控制誤差平均值計算一第一運算模式，及依據該等爐壓控制誤差平均值及該等爐壓控制輸出值變化量計算一第二運算模式；(b) calculating a first operation mode according to the temperature drop index and the average value of the furnace pressure control errors, and calculating a second operation according to the average value of the furnace pressure control errors and the change amount of the furnace pressure control output values mode;
(c) 依據一期望溫降指標利用該第一運算模式計算一期望爐壓控制誤差；(c) calculating a desired furnace pressure control error using the first operational mode based on a desired temperature drop indicator;
(d) 依據該出料爐門當次開啟後該設定時間內之爐壓控制輸出值變化量，利用該第二運算模式計算一估測爐壓控制誤差；(d) calculating an estimated furnace pressure control error by using the second calculation mode according to the amount of change in the furnace pressure control output value within the set time after the opening of the discharge furnace door;
(e) 依據該期望爐壓控制誤差及該估測爐壓控制誤差計算一爐壓修正量；及(e) calculating a furnace pressure correction amount based on the desired furnace pressure control error and the estimated furnace pressure control error;
(f) 依據該爐壓修正量及該爐壓設定值計算一當次所需爐壓調整值。(f) Calculate the required furnace pressure adjustment value according to the furnace pressure correction amount and the furnace pressure setting value.
本發明之爐壓控制方法僅需在每次出料過程中，計算出料爐門開啟後該設定時間內之爐壓控制輸出值變化量，即可計算出當次所需爐壓調整值(該次出料過程所需爐壓修正量)。藉此，可即時調整爐壓設定並確保抑制出料爐門開啟空氣吸入(高溫熱氣外溢與冷空氣吸入間維持最適平衡狀態)，以大幅降低溫降程度與變異量，改善鋼胚寬度方向溫差問題，以提升後續熱軋製程之穩定性，並且可減少爐氣氧濃度峰值，同時對加熱爐節能、爐內胚料銹損及NOx之抑制皆有增進功效。The furnace pressure control method of the invention only needs to calculate the change amount of the furnace pressure control output value within the set time after the furnace door is opened in each discharging process, and can calculate the current required furnace pressure adjustment value ( The amount of furnace pressure correction required for this discharge process). In this way, the furnace pressure setting can be adjusted immediately and the air intake of the discharge door can be suppressed (the optimal balance between the high temperature hot gas overflow and the cold air suction) to greatly reduce the temperature drop and the variation, and improve the temperature difference in the width direction of the steel. The problem is to improve the stability of the subsequent hot rolling process, and to reduce the peak oxygen concentration of the furnace gas, and at the same time improve the energy saving of the heating furnace, the rust loss of the furnace and the inhibition of NOx.
圖1顯示本發明爐壓控制方法之流程圖；圖2顯示本發明爐壓控制方法之邏輯方塊圖。配合參考圖1及圖2，首先參考步驟S11，獲得一出料爐門複數次開啟時間內之製程數據，每一次之製程數據包含一溫降指標、一爐壓控制誤差平均值及一爐壓控制輸出值變化量。1 is a flow chart showing a method of controlling the pressure of the present invention; and FIG. 2 is a logic block diagram showing a method of controlling the pressure of the present invention. Referring to FIG. 1 and FIG. 2, first referring to step S11, the process data of a plurality of opening times of the discharge furnace door is obtained, and the process data of each time includes a temperature drop index, an average value of the furnace pressure control error, and a furnace pressure. Controls the amount of change in the output value.
該溫降指標係為該出料爐門開啟時間內之溫降梯度，該爐壓控制誤差平均值係為該出料爐門開啟時間內之爐壓設定值與爐壓量測值的差值之平均值，該爐壓控制輸出值變化量係為一廢氣調節閥21門在該出料爐門開啟後一設定時間內之開度變化量(可以該出料爐門之開啟程度的百分比表示，例如半開表示為50%)。該爐壓量測值係由設置於加熱爐22內之爐壓感測器23所測得。The temperature drop index is the temperature drop gradient of the opening time of the discharge furnace door, and the average value of the furnace pressure control error is the difference between the set value of the furnace pressure and the measured value of the furnace pressure during the opening time of the discharge furnace door. The average value of the furnace pressure control output value is the amount of change in the opening degree of a door of the exhaust gas regulating valve 21 after the opening of the discharging furnace door (which can be expressed as a percentage of the opening degree of the discharging furnace door) , for example, half open is expressed as 50%). The furnace pressure measurement is measured by a furnace pressure sensor 23 provided in the heating furnace 22.
在本實施例中，係在加熱爐22中(例如在均熱區中)且在固定該爐壓設定值之下獲得該等製程數據。該設定時間係為4-10秒之間，該設定時間較佳係為6秒。In the present embodiment, the process data is obtained in the furnace 22 (e.g., in the soaking zone) and below the furnace setpoint. The set time is between 4 and 10 seconds, and the set time is preferably 6 seconds.
其中，在取得該設定時間內之爐壓控制輸出值變化量之部分，可依不同加熱爐22爐體之設計或操作特性進行調整，惟須滿足與爐壓控制誤差平均值之相關性，同時需保留足夠時間於該出料爐門關閉前進行爐壓之調整。Wherein, the part of the furnace pressure control output value obtained during the set time can be adjusted according to the design or operation characteristics of the furnace 22, but the correlation with the average value of the furnace pressure control error must be satisfied. Allow sufficient time to adjust the furnace pressure before the discharge door is closed.
關於該出料爐門開啟後所造成之溫度下降，除了考量該出料爐門開啟期間之溫度最高值與關閉後溫度最低值之差值，另外需考量因加熱爐22升溫加熱過程所造成之影響。整體觀之，因吸入空氣而造成加熱爐22內之總體溫降量係為該出料爐門開啟後之溫度下降量及爐溫升降造成之溫度修正量之和。該出料爐門開啟後之溫度下降量係為該出料爐門開啟期間之溫度最高值與該出料爐門關閉後一第一間隔時間內之溫度最低值之差。在本實施例中，該第一間隔時間係為300秒。Regarding the temperature drop caused by the opening of the discharge furnace door, in addition to considering the difference between the highest temperature value during the opening of the discharge furnace door and the lowest temperature value after the shutdown, it is also considered to be caused by the heating process of the heating furnace 22 influences. Overall, the total temperature drop in the heating furnace 22 due to the intake of air is the sum of the temperature drop after the opening of the discharge door and the temperature correction caused by the rise and fall of the furnace temperature. The temperature drop after the opening of the discharge furnace door is the difference between the highest temperature value during the opening of the discharge furnace door and the lowest temperature value during a first interval after the discharge furnace door is closed. In this embodiment, the first interval time is 300 seconds.
參考圖3，其顯示本發明出料爐門開啟後之時間-溫度關係圖。該出料爐門開啟後之總體溫降量=該出料爐門開啟後之溫度下降量ΔT1+爐溫升降造成之溫度修正量ΔT2。在此，爐溫升降造成之溫度修正量ΔT2可表示為：。其中，T1及t1分別為該出料爐門關閉前一第二間隔時間內之溫度最高值及時間點；t2為該出料爐門開啟期間之溫度最高值之時間點；t3為該出料爐門關閉後該第一間隔時間內之溫度最低值之時間點；T4及t4分別為爐門關閉後一第三間隔時間內之溫度最高值及時間點。在本實施例中，該第二間隔時間係為300秒，該第三間隔時間係為500秒。Referring to Figure 3, there is shown a time-temperature relationship diagram of the discharge door of the present invention after opening. The total temperature drop after the opening of the discharge furnace door = the temperature drop amount ΔT1 after the opening of the discharge furnace door + the temperature correction amount ΔT2 caused by the temperature rise and fall of the furnace. Here, the temperature correction amount ΔT2 caused by the temperature rise and fall of the furnace can be expressed as: . Wherein, T1 and t1 are respectively the highest temperature value and time point of the second interval time before the discharge furnace door is closed; t2 is the time point of the highest temperature value during the opening of the discharge furnace door; t3 is the discharge time The time point at which the temperature of the first interval is the lowest after the furnace door is closed; T4 and t4 are respectively the highest temperature value and time point in a third interval time after the door is closed. In this embodiment, the second interval is 300 seconds, and the third interval is 500 seconds.
出料爐門開啟時空氣會吸入加熱爐內，造成加熱爐內溫降。關於間接量化空氣吸入量有二：其一為出料爐門開啟所造成均熱區爐溫下降量；其二為爐氣氧濃度量測，空氣吸入會造成氧濃度量測出現峰值，其中每次出料爐門開啟之溫降量與氧濃度峰值，兩者呈正相關，溫降量愈大，則氧濃度峰值愈高，亦即表示空氣吸入量愈多。When the discharge door is opened, the air will be sucked into the heating furnace, causing the temperature drop in the heating furnace. There are two indirect quantitative air intakes: one is the temperature drop in the soaking zone caused by the opening of the discharge furnace door; the other is the oxygen concentration measurement of the furnace gas, and the air inhalation will cause the peak of the oxygen concentration measurement, each of which The temperature drop and oxygen concentration peak of the secondary discharge door are positively correlated. The higher the temperature drop, the higher the peak oxygen concentration, which means the more air intake.
圖4顯示本發明固定爐壓下，出料爐門開啟所導致之溫降量與氧濃度峰值相關圖；圖5顯示本發明爐壓控制誤差與溫降相關圖；圖6顯示本發明爐門開啟6秒內爐壓控制輸出變化，與爐門開啟期間平均控制誤差相關圖。Figure 4 is a graph showing the correlation between the temperature drop and the oxygen concentration peak caused by the opening of the discharge furnace door according to the present invention; Figure 5 is a graph showing the relationship between the furnace pressure control error and the temperature drop of the present invention; Turn on the furnace pressure control output change within 6 seconds, and the average control error correlation graph during the opening of the furnace door.
參考圖4，在固定爐壓設定下，每次出料爐門開啟之溫降量與氧濃度峰值兩者呈正相關，溫降量愈大，則氧濃度峰值愈高，亦即表示空氣吸入量愈多。在圖4中，爐門開啟次數為1810次；氧(O2 )濃度峰值可表示為：平均值±三倍標準差=0.61±3×0.25；溫降量可表示為：平均值±三倍標準差=8.17±3×2.79。參考圖5，爐壓控制平衡狀態之變化與該次爐門開啟所造成之溫降幅度呈負相關。在圖5中，爐門開啟次數為3126次；相關係數為0.5882。Referring to Figure 4, under the fixed furnace pressure setting, the temperature drop of each opening of the furnace door is positively correlated with the peak oxygen concentration. The larger the temperature drop, the higher the peak oxygen concentration, which means the air intake. The more. In Fig. 4, the number of opening of the furnace door is 1810 times; the peak value of oxygen (O 2 ) concentration can be expressed as: mean ± three standard deviation = 0.61 ± 3 × 0.25; the amount of temperature drop can be expressed as: mean ± three times Standard deviation = 8.17 ± 3 × 2.79. Referring to Figure 5, the change in the equilibrium state of the furnace pressure control is inversely related to the magnitude of the temperature drop caused by the opening of the furnace door. In Fig. 5, the number of opening of the oven door is 3126 times; the correlation coefficient is 0.5882.
參考圖6，利用爐門開啟後6秒內爐壓控制輸出值之變化量，可估測整個爐門開啟期間爐壓控制平均誤差，其呈高度負相關，且此關係僅反應爐壓控制迴路特性，與爐壓之設定值大小無關。在圖6中，爐門開啟次數為3126次；相關係數為0.8236。Referring to Fig. 6, using the variation of the furnace pressure control output value within 6 seconds after the furnace door is opened, the average error of the furnace pressure control during the entire furnace door opening period can be estimated, which is highly negatively correlated, and the relationship is only the reaction furnace pressure control loop. Characteristics, regardless of the set value of the furnace pressure. In Fig. 6, the number of opening of the oven door is 3126 times; the correlation coefficient is 0.8236.
再配合參考圖1及圖2，在步驟S12中，依據該等溫降指標及該等爐壓控制誤差平均值計算一第一運算模式，及依據該等爐壓控制誤差平均值及該等爐壓控制輸出值變化量計算一第二運算模式。Referring to FIG. 1 and FIG. 2 again, in step S12, a first operation mode is calculated according to the isothermal drop index and the average value of the furnace pressure control errors, and the average value of the furnace control errors is determined according to the furnaces. The pressure control output value change amount calculates a second operation mode.
經實際長時間加熱爐製程數據之蒐集與分析結果顯示，在出料過程之出料爐門開啟期間(約40~50秒)，爐壓控制誤差平均值與該次出料爐門開啟之溫降指標呈負相關(參考圖5)。因此，在本發明之方法中可利用迴歸分析方式依據爐壓控制誤差平均值及出料爐門開啟之溫降指標計算該第一運算模式。The collection and analysis results of the actual long-time heating furnace process data show that during the opening of the discharge furnace door during the discharge process (about 40~50 seconds), the average value of the furnace pressure control error and the temperature of the opening of the discharge furnace door The down indicator is negatively correlated (see Figure 5). Therefore, in the method of the present invention, the first operation mode can be calculated by the regression analysis method according to the average value of the furnace pressure control error and the temperature drop index of the opening of the furnace door.
其中，爐壓設定值係為固定，在出料爐門開啟後，若爐壓控制誤差(爐壓設定值-爐壓量測值)往負的方向移動，爐壓控制器24會持續打開廢氣調節閥21之開度，以縮小爐壓控制誤差，同時因均熱區溫降變大，表示空氣吸入量增加；反之，若爐壓控制誤差往正的方向移動，廢氣調節閥21之開度將會變小，且該次爐門開啟所導致之均熱區溫降也會變小，表示空氣吸入量減少。Wherein, the set value of the furnace pressure is fixed, and after the opening of the discharge furnace door, if the furnace pressure control error (the furnace pressure set value - the furnace pressure measurement value) moves in the negative direction, the furnace pressure controller 24 will continuously open the exhaust gas. Adjusting the opening degree of the valve 21 to reduce the furnace pressure control error, and at the same time, the temperature rise of the soaking zone becomes larger, indicating that the air intake amount is increased; conversely, if the furnace pressure control error is moved in the positive direction, the opening degree of the exhaust gas regulating valve 21 It will become smaller, and the temperature drop in the soaking zone caused by the opening of the door will also become smaller, indicating that the air intake is reduced.
上述現象說明爐壓並不是影響出料爐門開啟時加熱爐22內外氣體對流狀況之唯一因素，但整個出料爐門開啟期間之爐壓控制平衡狀態之變化，可用以估測空氣吸入所導致之溫降量。The above phenomenon indicates that the furnace pressure is not the only factor affecting the gas convection condition inside and outside the heating furnace 22 when the discharge furnace door is opened, but the change of the furnace pressure control equilibrium state during the opening of the entire discharge furnace door can be used to estimate the air suction. The amount of temperature drop.
另外，依據複數次量測且經數據分析，本發明之方法可利用出料爐門開啟後6秒(該設定時間)內之爐壓控制輸出值變化量，即可估測整個出料爐門開啟期間爐壓控制平均誤差，其中出料爐門開啟後6秒內之爐壓控制輸出值變化量與爐壓控制誤差平均值呈高度負相關，且此關係僅反應爐壓控制迴路特性，與爐壓設定值大小無關(參考圖6)。因此，在本發明之方法中可利用迴歸分析方式依據出料爐門開啟後之爐壓控制輸出值變化量與爐壓控制誤差平均值計算該第二運算模式。In addition, according to the plurality of measurements and data analysis, the method of the present invention can estimate the entire discharge door by using the change of the furnace pressure control output value within 6 seconds (the set time) after the opening of the discharge furnace door. The average error of the furnace pressure control during the opening period, wherein the change of the furnace pressure control output value within 6 seconds after the opening of the discharge furnace door is highly negatively correlated with the average value of the furnace pressure control error, and this relationship only reflects the characteristics of the furnace pressure control loop, and The furnace pressure setting value is irrelevant (refer to Figure 6). Therefore, in the method of the present invention, the second calculation mode can be calculated by the regression analysis method according to the furnace pressure control output value change amount after the discharge furnace door is opened and the furnace pressure control error average value.
要說明的是，經實際長時間加熱爐製程數據之蒐集與分析結果所建立第一運算模式及第二運算模式，可供計算加熱爐之每一次出料爐門開啟所需爐壓調整值，亦即，第一運算模式及第二運算模式係應用至每一次出料爐門開啟所進行之步驟S13~S16中。It should be noted that the first calculation mode and the second calculation mode are established through the collection and analysis results of the actual long-time heating furnace process data, and can be used to calculate the furnace pressure adjustment value required for each opening of the furnace door of the heating furnace. That is, the first operation mode and the second calculation mode are applied to steps S13 to S16 performed every time the discharge door is opened.
要強調的是，若取出料爐門開啟後較短時間(例如3秒)內之數據進行迴歸分析，則爐壓控制誤差平均值與該次出料爐門開啟之溫降指標、出料爐門開啟後之爐壓控制輸出值變化量與爐壓控制誤差平均值之相關性偏低，若取更長時間進行分析，雖可得到更高相關性，但將縮短爐壓設定修正補償之時間，影響抑制空氣吸入之成效。It should be emphasized that if the data within a short time (for example, 3 seconds) after the opening of the furnace door is taken for regression analysis, the average value of the furnace pressure control error and the temperature drop index of the discharge door opening, the discharge furnace The correlation between the change of the furnace pressure control output value after the door is opened and the average value of the furnace pressure control error is low. If the analysis is taken for a longer time, although the correlation can be obtained, the time for correcting the compensation of the furnace pressure setting will be shortened. , affecting the effectiveness of suppressing air inhalation.
在步驟S12中，該第一運算模式係表示為：溫降指標=C1×爐壓控制誤差(mm H2 O)+C2，依據不同加熱爐之出料爐門之製程數據，該第一運算模式係包含不同數值之C1及C2。在本實施例中，該第一運算模式係表示為：溫降指標=-0.8554×爐壓控制誤差(mm H2 O)+0.1801。另外，在步驟S12中，該第二運算模式係表示為：爐壓控制誤差(mm H2 O)=C3×控制輸出值變化量(%)+C4，依據不同加熱爐之出料爐門之製程數據，該第二運算模式包含不同數值之C3及C4。在本實施例中，該第二運算模式係表示為：爐壓控制誤差(mm H2 O)=-0.0504×控制輸出值變化量(%)+0.0732。In step S12, the first operation mode is expressed as: temperature drop index=C1×furnace pressure control error (mm H 2 O)+C2, according to process data of the discharge furnace door of different heating furnaces, the first operation The model contains C1 and C2 with different values. In the present embodiment, the first operation mode is expressed as: temperature drop index = -0.8554 × furnace pressure control error (mm H 2 O) + 0.1801. In addition, in step S12, the second operation mode is expressed as: furnace pressure control error (mm H 2 O) = C3 × control output value change amount (%) + C4, according to different furnace furnace discharge door Process data, the second mode of operation contains different values of C3 and C4. In the present embodiment, the second operation mode is expressed as: furnace pressure control error (mm H 2 O) = -0.0504 × control output value change amount (%) + 0.0732.
參考步驟S13，依據一期望溫降指標利用該第一運算模式計算一期望爐壓控制誤差。Referring to step S13, a desired furnace pressure control error is calculated using the first operational mode according to a desired temperature drop index.
參考步驟S14，依據該出料爐門當次開啟後該設定時間內之爐壓控制輸出值變化量，利用該第二運算模式計算一估測爐壓控制誤差。Referring to step S14, an estimated furnace pressure control error is calculated by using the second operation mode according to the amount of change in the furnace pressure control output value within the set time after the opening of the discharge furnace door.
其中，由加熱爐22之操作人員決定期望溫降值，該期望溫降值可依實際加熱爐22操作狀況決定，並依據溫降指標利用該第一運算模式計算一期望爐壓控制誤差。例如，期望之溫降指標為0.1℃/s(若出料爐門開啟時間為45s，則表示該次出料爐門開關所造成之期望溫降值約4.5度)，則以該第一運算模式計算得之期望爐壓控制誤差約為0.094 mm H2 O。The desired temperature drop value is determined by the operator of the heating furnace 22, and the desired temperature drop value may be determined according to the actual operating condition of the heating furnace 22, and a desired furnace pressure control error is calculated by using the first calculation mode according to the temperature drop index. For example, the expected temperature drop index is 0.1 ° C / s (if the discharge door opening time is 45 s, it means that the expected temperature drop caused by the discharge door switch is about 4.5 degrees), then the first operation The desired furnace pressure control error calculated from the mode is approximately 0.094 mm H 2 O.
並且，依據該出料爐門當次開啟後該設定時間(例如6秒)內獲得之爐壓控制輸出值變化量，利用該第二運算模式計算該估測爐壓控制誤差。And, according to the change amount of the furnace pressure control output value obtained in the set time (for example, 6 seconds) after the discharge furnace door is turned on, the estimated furnace pressure control error is calculated by using the second calculation mode.
參考步驟S15，依據該期望爐壓控制誤差及該估測爐壓控制誤差計算一爐壓修正量。在本實施例中，在步驟S15之後另包括一增益調整該爐壓修正量之步驟，所計算之該爐壓修正量經控制增益25後，再將其加入該爐壓設定值，直到該次出料過程結束(爐門關閉)。其中，控制增益25可依加熱爐22實際測試量測結果調整。Referring to step S15, a furnace pressure correction amount is calculated according to the desired furnace pressure control error and the estimated furnace pressure control error. In this embodiment, after step S15, a step of adjusting the furnace pressure correction amount is further included, and the calculated furnace pressure correction amount is controlled by the control gain 25, and then added to the furnace pressure setting value until the time The discharge process ends (the furnace door is closed). Wherein, the control gain 25 can be adjusted according to the actual test measurement result of the heating furnace 22.
參考步驟S16，依據該爐壓修正量及該爐壓設定值計算一當次所需爐壓調整值。一爐壓控制器24依據該當次所需爐壓調整值控制廢氣調節閥21之開度，以調節補償加熱爐22中之爐壓大小。Referring to step S16, a required furnace pressure adjustment value is calculated according to the furnace pressure correction amount and the furnace pressure setting value. A furnace pressure controller 24 controls the opening degree of the exhaust gas regulating valve 21 in accordance with the current required furnace pressure adjustment value to adjust the magnitude of the furnace pressure in the heating furnace 22.
圖7顯示經本發明爐壓控制方法調整後，出料爐門開啟所導致之溫降量與氧濃度峰值相關圖。在圖7中，爐門開啟次數為907次；氧(O2 )濃度峰值可表示為：平均值±三倍標準差=0.28±3×0.23；溫降量可表示為：平均值±三倍標準差=4.9±3×1.98。相較於圖4(未經本發明爐壓控制方法調整)，不論溫降量或氧濃度峰值，其平均值與變異程度皆明顯下降。Fig. 7 is a graph showing the correlation between the temperature drop caused by the opening of the discharge furnace door and the peak value of the oxygen concentration after the furnace pressure control method of the present invention is adjusted. In Fig. 7, the number of opening of the furnace door is 907 times; the peak value of oxygen (O 2 ) concentration can be expressed as: mean ± three standard deviation = 0.28 ± 3 × 0.23; the amount of temperature drop can be expressed as: mean ± three times Standard deviation = 4.9 ± 3 × 1.98. Compared with Fig. 4 (not adjusted by the furnace pressure control method of the present invention), the average value and the degree of variation are significantly decreased regardless of the temperature drop or the peak oxygen concentration.
本發明之爐壓控制方法經實際運用在熱軋產線，其結果顯示，無論是均熱區溫降量或爐氣氧濃度峰值，其平均值與變異程度皆有明顯下降。以同一加熱爐而言，溫降量由8.17±2.97度下降至4.9±1.98度；氧濃度峰值由0.61±0.25%下降至0.28±0.23%。因此，本發明之爐壓控制方法確實能有效抑制出料爐門開啟時吸入空氣。The furnace pressure control method of the present invention is practically applied to a hot rolling production line, and the results show that the average value and the degree of variation of the soaking zone are significantly decreased regardless of the temperature drop in the soaking zone or the peak oxygen concentration in the furnace gas. In the same furnace, the temperature drop decreased from 8.17±2.97 degrees to 4.9±1.98 degrees; the peak oxygen concentration decreased from 0.61±0.25% to 0.28±0.23%. Therefore, the furnace pressure control method of the present invention can effectively suppress the intake of air when the discharge furnace door is opened.
本發明之爐壓控制方法僅需在每次出料過程中，計算出料爐門開啟後該設定時間內之爐壓控制輸出值變化量，即可計算出當次所需爐壓調整值(該次出料過程所需爐壓修正量)。藉此，可即時調整爐壓設定並確保抑制出料爐門開啟空氣吸入(高溫熱氣外溢與冷空氣吸入間維持最適平衡狀態)，以大幅降低溫降程度與變異量，改善鋼胚寬度方向溫差問題，以提升後續熱軋製程之穩定性，並且可減少爐氣氧濃度峰值，同時對加熱爐節能、爐內胚料銹損及NOx之抑制皆有增進功效。The furnace pressure control method of the invention only needs to calculate the change amount of the furnace pressure control output value within the set time after the furnace door is opened in each discharging process, and can calculate the current required furnace pressure adjustment value ( The amount of furnace pressure correction required for this discharge process). In this way, the furnace pressure setting can be adjusted immediately and the air intake of the discharge door can be suppressed (the optimal balance between the high temperature hot gas overflow and the cold air suction) to greatly reduce the temperature drop and the variation, and improve the temperature difference in the width direction of the steel. The problem is to improve the stability of the subsequent hot rolling process, and to reduce the peak oxygen concentration of the furnace gas, and at the same time improve the energy saving of the heating furnace, the rust loss of the furnace and the inhibition of NOx.
上述實施例僅為說明本發明之原理及其功效，並非限制本發明，因此習於此技術之人士對上述實施例進行修改及變化仍不脫本發明之精神。本發明之權利範圍應如後述之申請專利範圍所列。The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the scope of the present invention. The scope of the invention should be as set forth in the appended claims.
21．．．廢氣調節閥twenty one. . . Exhaust gas regulating valve
22．．．加熱爐twenty two. . . Heating furnace
23．．．爐壓感測器twenty three. . . Furnace pressure sensor
24．．．爐壓控制器twenty four. . . Furnace pressure controller
25．．．控制增益25. . . Control gain
圖1顯示本發明爐壓控制方法之流程圖；Figure 1 is a flow chart showing the method of controlling the pressure of the present invention;
圖2顯示本發明爐壓控制方法之邏輯方塊圖；及Figure 2 is a logic block diagram showing the furnace pressure control method of the present invention;
圖3顯示本發明出料爐門開啟後之時間-溫度關係圖；Figure 3 is a graph showing the time-temperature relationship after the opening of the discharge furnace door of the present invention;
圖4顯示本發明固定爐壓下，出料爐門開啟所導致之溫降量與氧濃度峰值相關圖；Figure 4 is a graph showing the relationship between the temperature drop caused by the opening of the furnace door and the peak of the oxygen concentration in the fixed furnace of the present invention;
圖5顯示本發明爐壓控制誤差與溫降相關圖；Figure 5 is a graph showing the relationship between the furnace pressure control error and the temperature drop of the present invention;
圖6顯示本發明爐門開啟6秒內爐壓控制輸出變化，與爐門開啟期間平均控制誤差相關圖；及Figure 6 is a graph showing the correlation between the change of the furnace pressure control output and the average control error during the opening of the furnace door in the 6 seconds after the opening of the furnace door of the present invention;
圖7顯示經本發明爐壓控制方法調整後，出料爐門開啟所導致之溫降量與氧濃度峰值相關圖。Fig. 7 is a graph showing the correlation between the temperature drop caused by the opening of the discharge furnace door and the peak value of the oxygen concentration after the furnace pressure control method of the present invention is adjusted.
(無元件符號說明)(no component symbol description)
Claims (12)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW100100010A TWI413554B (en) | 2011-01-03 | 2011-01-03 | Furnace pressure control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW100100010A TWI413554B (en) | 2011-01-03 | 2011-01-03 | Furnace pressure control method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| TW201228742A TW201228742A (en) | 2012-07-16 |
| TWI413554B true TWI413554B (en) | 2013-11-01 |
Family
ID=46933765
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| TW100100010A TWI413554B (en) | 2011-01-03 | 2011-01-03 | Furnace pressure control method |
Country Status (1)
| Country | Link |
|---|---|
| TW (1) | TWI413554B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111822518B (en) * | 2020-06-16 | 2022-06-10 | 首钢京唐钢铁联合有限责任公司 | Method for controlling fine line defects of IF steel edge |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002157023A (en) * | 2000-11-17 | 2002-05-31 | Daido Steel Co Ltd | Furnace pressure control system |
| TW524956B (en) * | 2001-01-17 | 2003-03-21 | Kawasaki Steel Co | Heating furnace with regenerative burners and method of operating the heating furnace |
| US20090176181A1 (en) * | 2007-11-12 | 2009-07-09 | Micrel, Inc. | System and method of improved pressure control in horizontal diffusion furnace scavenger system for controlling silicon oxide growth |
| CN101339058B (en) * | 2008-08-14 | 2010-07-21 | 中冶长天国际工程有限责任公司 | Ignition furnace discharge gas flow quantity checking method and system |
-
2011
- 2011-01-03 TW TW100100010A patent/TWI413554B/en not_active IP Right Cessation
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002157023A (en) * | 2000-11-17 | 2002-05-31 | Daido Steel Co Ltd | Furnace pressure control system |
| TW524956B (en) * | 2001-01-17 | 2003-03-21 | Kawasaki Steel Co | Heating furnace with regenerative burners and method of operating the heating furnace |
| US20090176181A1 (en) * | 2007-11-12 | 2009-07-09 | Micrel, Inc. | System and method of improved pressure control in horizontal diffusion furnace scavenger system for controlling silicon oxide growth |
| CN101339058B (en) * | 2008-08-14 | 2010-07-21 | 中冶长天国际工程有限责任公司 | Ignition furnace discharge gas flow quantity checking method and system |
Also Published As
| Publication number | Publication date |
|---|---|
| TW201228742A (en) | 2012-07-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2013513542A5 (en) | ||
| KR20130051506A (en) | Method and device for controlling furnace pressure of continuous annealing furnace | |
| CN106694567A (en) | Heating method for IF steel in ferrite rolling | |
| TWI413554B (en) | Furnace pressure control method | |
| JP5640647B2 (en) | Method and apparatus for measuring surface temperature of steel in furnace | |
| JP4998655B2 (en) | Combustion control method for continuous heating furnace | |
| JP2016168590A (en) | Coal feed amount control method to coal crushing mill, and device therefor | |
| CN104805277B (en) | Temperature control method for pulse-type slab heating furnace | |
| CN113046544B (en) | Air-fuel ratio control method and control system for continuous annealing furnace | |
| JP5423443B2 (en) | Method for calculating fuel flow rate in continuous heating furnace, method for producing steel material, and continuous heating furnace | |
| CN109112288B (en) | Temperature adjusting method of annealing furnace | |
| TWI421134B (en) | Furnace pressure control system and method | |
| TWI544196B (en) | Method for automatically controlling temperature of continuous reheating furnace | |
| RU73668U1 (en) | SYSTEM OF TWO-LEVEL REGULATION BY THE HEAT PROCESS OF THE HEATING FURNACE | |
| JP6155477B2 (en) | Coke oven combustion control method and apparatus | |
| US20190313651A1 (en) | Method for the Open-Loop and/or Closed-Loop Control of the Gas Thoroughput in the Baking Chamber of a Baking Device | |
| TWI512258B (en) | Energy saving method of setting the furnace pressure | |
| KR101808420B1 (en) | Damper control apparatus for heat insulation device of rolled materials and method thereof | |
| CN107655030A (en) | Heat storage type combustion Temperature Field Control method | |
| JP2024010812A (en) | Control method for combustion air flow rate, manufacturing method for metal plate and continuous type heating furnace | |
| JP7155988B2 (en) | Method for detecting defective combustion of radiant tube burner | |
| JP2013221211A (en) | Method for designing pid controller for furnace temperature control of continuous annealing furnace, pid controller, and method for controlling furnace temperature of continuous annealing furnace | |
| TWI424134B (en) | Method of controlling the oxygen content of combustion furnace over / under - oxygen combustion state and combustion exhaust gas | |
| JP2021055137A (en) | Furnace pressure control device and furnace pressure control method for continuous heating furnace | |
| JP5919774B2 (en) | Coke oven operation method and operation management device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MM4A | Annulment or lapse of patent due to non-payment of fees |