TWI515054B - Method of cooling hot rolled steel sheet - Google Patents

Method of cooling hot rolled steel sheet Download PDF

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TWI515054B
TWI515054B TW101146092A TW101146092A TWI515054B TW I515054 B TWI515054 B TW I515054B TW 101146092 A TW101146092 A TW 101146092A TW 101146092 A TW101146092 A TW 101146092A TW I515054 B TWI515054 B TW I515054B
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cooling
hot
steel sheet
rolled steel
temperature
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TW201422327A (en
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明石透
栗山進吾
伊藤健郎
田崎文規
野口浩嗣
二階堂仁之
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新日鐵住金股份有限公司
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熱軋鋼板冷卻方法 Hot rolled steel plate cooling method 技術領域 Technical field

本發明係有關於一種用於冷卻業經精軋機之熱軋之熱軋鋼板之熱軋鋼板冷卻方法。 The present invention relates to a method for cooling a hot rolled steel sheet for use in cooling hot rolled steel sheets of a hot rolling mill.

背景技術 Background technique

諸如汽車及工業機械等所使用之熱軋鋼板,一般係經粗軋步驟及精軋步驟而製成。圖21即模式地顯示習知之熱軋鋼板之製造方法者。熱軋鋼板之製造步驟中,首先係藉粗軋機201輥軋已調整為預定之組成之鐵水經連續鑄造而得之鋼胚S後,進而藉由複數之輥軋台202a~202d所構成之精軋機203進行熱軋,而形成預定厚度之熱軋鋼板H。其次,藉自冷卻裝置211注入之冷卻水冷卻前述熱軋鋼板H後,再藉盤捲裝置212加以捲成鋼捲狀。 Hot rolled steel sheets used in automobiles, industrial machines, and the like are generally produced by a rough rolling step and a finishing rolling step. Fig. 21 is a view schematically showing a method of manufacturing a conventional hot-rolled steel sheet. In the manufacturing step of the hot-rolled steel sheet, first, the rough-rolling mill 201 rolls and rolls the molten steel which has been adjusted to a predetermined composition by continuous casting, and then consists of a plurality of rolling stations 202a to 202d. The finishing mill 203 performs hot rolling to form a hot rolled steel sheet H having a predetermined thickness. Next, the hot-rolled steel sheet H is cooled by the cooling water injected from the cooling device 211, and then wound into a coil shape by the coiling device 212.

冷卻裝置211係一般用於對自精軋機203送入之熱軋鋼板H實施所謂層流冷卻之設備。該冷卻裝置211可對移動於滑出台上之熱軋鋼板H上面自垂直方向之上方經冷卻噴嘴而噴射冷卻水作為噴流水,並對熱軋鋼板H之下面經層流管而噴射冷卻水作為噴流水,以冷卻熱軋鋼板H。 The cooling device 211 is generally used for performing so-called laminar cooling of the hot-rolled steel sheet H fed from the finishing mill 203. The cooling device 211 can spray cooling water as a jet water through a cooling nozzle from above the vertical direction on the hot-rolled steel sheet H that is moved on the slide table, and spray cooling water on the lower surface of the hot-rolled steel sheet H through the laminar flow tube. Spray water to cool the hot rolled steel sheet H.

其次,迄今,諸如專利文獻1中,已揭露一種藉減少厚鋼板之上下面之表面溫度差而避免前述鋼板之形狀瑕疵之技術。依據前述專利文獻1所揭露之技術,可基於冷卻裝置進行冷卻時藉溫度計同時測定鋼板之上面及下面之表面溫度所得之表面溫度差而調整朝鋼板之上面及下面供給之冷卻水之水量比。 Next, heretofore, for example, Patent Document 1 has disclosed a technique for avoiding the shape of the steel sheet by reducing the surface temperature difference between the upper and lower portions of the thick steel plate. According to the technique disclosed in the above Patent Document 1, the water amount ratio of the cooling water supplied to the upper surface and the lower surface of the steel sheet can be adjusted based on the surface temperature difference obtained by simultaneously measuring the surface temperatures of the upper and lower surfaces of the steel sheet by the thermometer while cooling.

又,諸如專利文獻2則揭露了一種於精軋機之鄰接之2個軋台間使用噴霧器而進行被輥軋材之冷卻,而使被輥軋材之γ-α變態開始及結束,以避免軋台間之送板性之惡化之技術。 Further, for example, Patent Document 2 discloses that a pulverized material is cooled by using a sprayer between two adjacent rolling stands of a finishing mill to start and end the γ-α transformation of the rolled material to avoid rolling. The technology of the deterioration of the board between the stations.

又,諸如專利文獻3則揭露了一種藉設置於輥軋機之出口側之傾斜度計而測定鋼板先端之傾斜度,並對應上述已測得之傾斜度而朝寬度方向改變冷卻水流量並加以調整,以避免鋼板穿孔之技術。 Further, for example, Patent Document 3 discloses that the inclination of the tip end of the steel sheet is measured by an inclination meter provided on the exit side of the rolling mill, and the flow rate of the cooling water is changed and adjusted in the width direction in accordance with the measured inclination. To avoid the technique of perforation of steel plates.

進而,諸如專利文獻4則揭露了一種以消除熱軋鋼板之板寬方向上之波形之板厚分布,並使板寬方向上之板厚均一為目的,而將熱軋鋼板之板寬方向上之最高導熱率與最低導熱率之差控制在預定值之範圍內之技術。 Further, for example, Patent Document 4 discloses a method of eliminating the thickness distribution of the waveform in the width direction of the hot-rolled steel sheet and uniformizing the thickness in the sheet width direction, and the sheet width direction of the hot-rolled steel sheet is The technique in which the difference between the highest thermal conductivity and the lowest thermal conductivity is controlled within a predetermined value range.

在此,藉圖21所示之製造方法而製成之熱軋鋼板H可能諸如圖22所示般,於冷卻裝置211之滑出台(以下亦稱為「ROT」)之輸送輥220上在輥軋方向(圖22中之箭號方向)上形成波形。此時,熱軋鋼板H之上面及下面之冷卻將發生落差。即,將因熱軋鋼板H本身之波形所導致之冷卻偏差,而導致無法朝輥軋方向進行均一之冷卻之問題 Here, the hot-rolled steel sheet H produced by the manufacturing method shown in Fig. 21 may be on the conveying roller 220 of the sliding device (hereinafter also referred to as "ROT") of the cooling device 211 as shown in Fig. 22 A waveform is formed in the rolling direction (arrow direction in Fig. 22). At this time, the cooling of the upper surface and the lower surface of the hot-rolled steel sheet H will fall. That is, the cooling variation caused by the waveform of the hot-rolled steel sheet H itself causes a problem that uniform cooling cannot be performed in the rolling direction.

因此,諸如專利文獻5即揭露一種於輥軋方向上已形成波形之鋼板上,為使前述鋼板之冷卻均一化,而使上部冷卻與下部冷卻之冷卻能力相同,以使前述鋼板之上部之積水與下部之輥台輥輪之距離之影響最小化之技術。 Therefore, for example, Patent Document 5 discloses a steel sheet having a corrugated shape in the rolling direction, in order to uniformize the cooling of the steel sheet, so that the cooling ability of the upper cooling portion and the lower cooling portion is the same, so that the water in the upper portion of the steel sheet is accumulated. The technique of minimizing the influence of the distance from the lower roller table roller.

【先行技術文獻】 [First technical literature] 【專利文獻】 [Patent Literature]

【專利文獻1】:日本專利特開2005-74463號公報 [Patent Document 1]: Japanese Patent Laid-Open Publication No. 2005-74463

【專利文獻2】日本專利特開平5-337505號公報 [Patent Document 2] Japanese Patent Laid-Open No. Hei 5-337505

【專利文獻3】日本專利特開2005-271052號公報 [Patent Document 3] Japanese Patent Laid-Open Publication No. 2005-271052

【專利文獻4】日本專利特開2003-48003號公報 [Patent Document 4] Japanese Patent Laid-Open Publication No. 2003-48003

【專利文獻5】日本專利特開平6-328117號公報 [Patent Document 5] Japanese Patent Laid-Open No. Hei 6-328117

發明概要 Summary of invention

然而,專利文獻1之冷卻方法並未考量熱軋鋼板在輥軋方向上形成波形之情形。上述形成波形之熱軋鋼板H則如圖22所示,可能於波形之底部與輸送輥220局部接觸。且,熱軋鋼板H亦可能於波形底部與設置作為用於避免熱軋鋼板H落入輸送輥220彼此之間之支持體之護坦(圖22中並未圖示)局部接觸。波形之熱軋鋼板H中,與輸送輥220或護坦局部接觸之部分則易因接觸除熱而較其它部分更易冷卻。因此,將導致熱軋鋼板H之冷卻不均之問題。即,專利文獻1並未考量熱軋鋼板為波形而造成輸送輥及護坦與熱軋鋼板局部接觸,而其接觸部分因接觸除熱而容易冷卻之情形。故 而,如上而形成波形之熱軋鋼板可能無法均一地冷卻。 However, the cooling method of Patent Document 1 does not consider the case where the hot-rolled steel sheet is formed into a waveform in the rolling direction. The above-described waveform-formed hot-rolled steel sheet H is partially contacted with the conveying roller 220 at the bottom of the waveform as shown in Fig. 22 . Further, the hot-rolled steel sheet H may also be in partial contact with the bottom of the wave and the guard (not shown in FIG. 22) provided as a support for preventing the hot-rolled steel sheet H from falling between the transport rollers 220. In the corrugated hot-rolled steel sheet H, the portion in contact with the conveying roller 220 or the apron is easily cooled by contact with heat and is more easily cooled than other portions. Therefore, there is a problem that the cooling of the hot-rolled steel sheet H is uneven. That is, Patent Document 1 does not consider that the hot-rolled steel sheet has a corrugated shape, and the conveying roller and the apron are partially in contact with the hot-rolled steel sheet, and the contact portion thereof is easily cooled by contact with heat. Therefore However, the hot rolled steel sheet in which the waveform is formed as described above may not be uniformly cooled.

又,專利文獻2所揭露之技術係於精軋機之軋台間使硬度較低(柔軟)之極低碳鋼進行γ-α變態者,目的則不在進行均一之冷卻。且,專利文獻2之發明與被輥軋材在輥軋方向上形成波形時,或被輥軋材為拉伸強度(TS)800MPa以上之所謂稱為高張力之鋼材時之相關冷卻並無關聯,故在被輥軋材為形成波形之熱軋鋼板時及硬度較高之鋼材時,可能無法進行均一之冷卻。 Further, the technique disclosed in Patent Document 2 is to perform γ-α metamorphism between the rolling stands of the finishing mill to make the ultra-low carbon steel having a low hardness (softness), and the purpose is not to perform uniform cooling. Further, the invention of Patent Document 2 is not related to the cooling of the rolled material in the rolling direction, or the related cooling of the so-called high-tensile steel having a tensile strength (TS) of 800 MPa or more. Therefore, when the rolled material is a hot rolled steel sheet having a corrugated shape and a steel having a high hardness, uniform cooling may not be performed.

又,專利文獻3之冷卻方法係測定鋼板之寬度方向之傾斜度,而調整上述傾斜度較大之部分之冷卻水流量。然而,一旦改變鋼板之板寬方向之冷卻水流量,則難以使前述鋼板之板寬方向之溫度均一。進而,專利文獻3亦未考量熱軋鋼板在輥軋方向上形成波形之情形,而可能如上所述般無法均一冷卻熱軋鋼板。 Further, in the cooling method of Patent Document 3, the inclination of the width direction of the steel sheet is measured, and the flow rate of the cooling water in the portion where the inclination is large is adjusted. However, once the flow rate of the cooling water in the width direction of the steel sheet is changed, it is difficult to make the temperature in the sheet width direction of the steel sheet uniform. Further, Patent Document 3 does not consider the case where the hot-rolled steel sheet is formed into a wave shape in the rolling direction, and it is possible to uniformly cool the hot-rolled steel sheet as described above.

又,專利文獻4之冷卻係在精軋機軋輥咬入之前之熱軋鋼板之冷卻,故無法應用於業經精軋而形成預定厚度之熱軋鋼板。進而,專利文獻4亦未考量熱軋鋼板在輥軋方向上形成波形之情形,而可能如上述般無法使熱軋鋼板朝其輥軋方向均一地冷卻。 Further, the cooling of Patent Document 4 is cooled by the hot-rolled steel sheet before the finish rolling of the finishing mill, and therefore cannot be applied to a hot-rolled steel sheet which has been subjected to finish rolling to form a predetermined thickness. Further, Patent Document 4 does not consider the case where the hot-rolled steel sheet is formed into a wave shape in the rolling direction, and it is possible to uniformly cool the hot-rolled steel sheet in the rolling direction as described above.

又,專利文獻5之冷卻方法中,上部冷卻之冷卻能力除自上部注水噴嘴朝鋼板供給之冷卻水之冷卻以外,亦包括鋼板上部之積水所致之冷卻。上述積水則受鋼板上形成之波形之傾斜度及鋼板之送板速度所影響,故無法嚴格界定積水對鋼板之冷卻能力。如此,即難以正確控制上 部冷卻之冷卻能力。因此,亦難以使上部冷卻與下部冷卻之冷卻能力相同。甚且,欲使上部冷卻與下部冷卻之冷卻能力相同時,雖已例示該等冷卻能力之決定方法之一例,但並未揭露普遍性之決定方法。因此,專利文獻5之冷卻方法可能無法均一地冷卻熱軋鋼板。 Further, in the cooling method of Patent Document 5, the cooling ability of the upper cooling includes cooling of the cooling water supplied from the upper water injection nozzle to the steel sheet, and also includes cooling by the accumulated water in the upper portion of the steel sheet. The above-mentioned accumulated water is affected by the inclination of the waveform formed on the steel plate and the plate feeding speed of the steel plate, so the cooling ability of the accumulated water to the steel plate cannot be strictly defined. So, it is difficult to control it correctly The cooling capacity of the cooling. Therefore, it is also difficult to make the cooling ability of the upper cooling and the lower cooling the same. Further, when the cooling ability of the upper cooling and the lower cooling is the same, an example of the method for determining the cooling ability is exemplified, but the method for determining the generality is not disclosed. Therefore, the cooling method of Patent Document 5 may fail to uniformly cool the hot rolled steel sheet.

本發明即有鑑於上述之問題而設計,其目的則在均一地冷卻業經精軋機之熱軋之熱軋鋼板。 The present invention has been devised in view of the above problems, and its object is to uniformly cool a hot rolled steel sheet which has been hot rolled by a finishing mill.

本發明為解決上述問題以達成其目的而採用以下之方法。即, The present invention adopts the following method in order to solve the above problems in order to achieve the object. which is,

(1)本發明一態樣之熱軋鋼板冷卻方法係將業經精軋機之熱軋後之熱軋鋼板在設於其送板路徑上之冷卻區間中加以冷卻,其特徵在於包含以下步驟:目標比率設定步驟,基於預先實驗性地在使前述熱軋鋼板之傾斜度及送板速度為一定值之條件下預先求出之代表前述熱軋鋼板之上下面之導熱係數之比率之上下導熱係數比率X與前述熱軋鋼板之冷卻中或冷卻後之溫度標準偏差Y之相關關係之相關資料,而將可使前述溫度標準偏差Y為最小值Ymin之上下導熱係數比率X1設定為目標比率Xt;及,冷卻控制步驟,控制前述冷卻區間內之前述熱軋鋼板之上面冷卻除熱量與下面冷卻除熱量之至少一方,以使前述冷卻區間內之前述熱軋鋼板之上下導熱係數比率X與前述目標比率Xt一致。 (1) A method for cooling a hot-rolled steel sheet according to an aspect of the present invention is to cool a hot-rolled steel sheet which has been hot-rolled by a finishing mill in a cooling section provided on a conveying path thereof, and is characterized by comprising the following steps: The ratio setting step is based on preliminarily determining the ratio of the thermal conductivity of the hot-rolled steel sheet above and below the ratio of the thermal conductivity of the hot-rolled steel sheet under the condition that the inclination of the hot-rolled steel sheet and the sheet feeding speed are constant. The correlation between X and the temperature standard deviation Y of the hot-rolled steel sheet during cooling or after cooling, and the thermal conductivity coefficient ratio X1 above the minimum temperature Ymin can be set as the target ratio Xt; a cooling control step of controlling at least one of an upper heat removal heat removal amount and a lower heat removal heat removal amount of the hot-rolled steel sheet in the cooling zone so that the thermal conductivity ratio X of the hot-rolled steel sheet in the cooling section is higher than the target ratio Xt is consistent.

(2)上述(1)所揭露之熱軋鋼板冷卻方法中,於前述目標比率設定步驟中,亦可基於前述相關資料,而將可 將前述溫度標準偏差Y控制在最小值Ymin至最小值Ymin+10℃以內之範圍內之上下導熱係數比率X設定為前述目標比率Xt。 (2) The hot-rolled steel sheet cooling method disclosed in the above (1), in the target ratio setting step, may be based on the aforementioned related information The temperature standard deviation Y is controlled to be within the range of the minimum value Ymin to the minimum value Ymin + 10 ° C. The upper and lower thermal conductivity ratio X is set to the aforementioned target ratio Xt.

(3)上述(1)或(2)所揭露之熱軋鋼板冷卻方法中,亦可就前述傾斜度及前述送板速度之值不同之複數條件個別準備前述相關資料,前述目標比率設定步驟中,則基於前述複數之相關資料內對應前述傾斜度及前述送板速度之實測值之相關資料,而設定前述目標比率Xt。 (3) In the method for cooling a hot-rolled steel sheet disclosed in the above (1) or (2), the related information may be separately prepared for a plurality of conditions in which the values of the inclination and the sheet feeding speed are different, and the target ratio setting step is And setting the target ratio Xt based on the correlation data corresponding to the measured value of the inclination and the plate feeding speed in the correlation data of the plurality of numbers.

(4)上述(3)所揭露之熱軋鋼板冷卻方法中,前述相關資料亦可為以迴歸公式顯示前述上下導熱係數比率X與前述溫度標準偏差Y之相關關係之資料。 (4) In the method for cooling a hot-rolled steel sheet disclosed in the above (3), the related information may be a data showing a correlation between the upper and lower thermal conductivity ratios X and the temperature standard deviation Y by a regression equation.

(5)上述(4)所揭露之熱軋鋼板冷卻方法中,前述迴歸公式亦可為藉線性迴歸而導出者。 (5) In the method for cooling a hot-rolled steel sheet disclosed in the above (4), the regression formula may be derived by linear regression.

(6)上述(3)所揭露之熱軋鋼板冷卻方法中,前述相關資料亦可為以表格顯示前述上下導熱係數比率X與前述溫度標準偏差Y之相關關係之資料。 (6) In the method for cooling a hot-rolled steel sheet disclosed in the above (3), the related information may be a table showing a correlation between the upper and lower thermal conductivity ratios X and the temperature standard deviation Y.

(7)上述(1)或(2)所揭露之熱軋鋼板冷卻方法中,其中亦可進而包含以下步驟:溫度測定步驟,依時間序列而測定前述冷卻區間之下游側之前述熱軋鋼板之溫度;溫度平均值算出步驟,基於前述溫度之測定結果而算出前述溫度之時間序列平均值;及,冷卻除熱量調整步驟,調整前述冷卻區間內之前述熱軋鋼板之前述上面冷卻除熱量與前述下面冷卻除熱量之合計值,以使前述溫度之時間序列平均值與預定之目標溫度一致。 (7) The method for cooling a hot-rolled steel sheet according to the above (1) or (2), further comprising the step of: measuring a temperature of the hot-rolled steel sheet on a downstream side of the cooling section in a time series a temperature average value calculation step of calculating a time-series average value of the temperature based on the measurement result of the temperature; and a cooling heat removal adjustment step of adjusting the upper surface cooling heat removal amount of the hot-rolled steel sheet in the cooling zone and the foregoing The total value of the heat removal is cooled below so that the time-series average of the aforementioned temperatures coincides with the predetermined target temperature.

(8)上述(1)或(2)所揭露之熱軋鋼板冷卻方法中,其中亦可進而包含以下步驟:溫度測定步驟,依時間序列而測定前述冷卻區間之下游側之前述熱軋鋼板之溫度;變動速度測定步驟,依時間序列而測定與前述冷卻區間之下游側之前述熱軋鋼板之溫度測定部位相同之部位上之前述熱軋鋼板之垂直方向之變動速度;控制方向決定步驟,在以前述熱軋鋼板之垂直方向之上方為正值時,於前述變動速度為正值之領域內,在前述熱軋鋼板之溫度相對於前述熱軋鋼板之波形1周期以上之範圍之平均溫度而較低時,將前述上面冷卻除熱量減少之方向及前述下面冷卻除熱量增加之方向之至少一方決定為控制方向,而在前述熱軋鋼板之溫度相對於前述平均溫度而較高時,將前述上面冷卻除熱量增加之方向及前述下面冷卻除熱量減少之方向之至少一方決定為前述控制方向,並於前述變動速度為負值之領域內,在前述熱軋鋼板之溫度相對於前述平均溫度而較低時,將前述上面冷卻除熱量增加之方向及前述下面冷卻除熱量減少之方向之至少一方決定為前述控制方向,而在前述熱軋鋼板之溫度相對於前述平均溫度而較高時,將前述上面冷卻除熱量減少之方向及前述下面冷卻除熱量增加之方向之至少一方決定為前述控制方向;及,冷卻除熱量調整步驟,基於前述控制方向決定步驟中已決定之前述控制方向,而調整前述冷卻區間內之前述熱軋鋼板之前述上面冷卻除熱量及前述下面冷卻除熱量之至少一方。 (8) The method for cooling a hot-rolled steel sheet according to the above (1) or (2), further comprising the step of: measuring a temperature of the hot-rolled steel sheet on a downstream side of the cooling section in a time series; a temperature; a fluctuation speed measuring step of measuring a rate of change in a vertical direction of the hot-rolled steel sheet at a portion identical to a temperature measurement portion of the hot-rolled steel sheet on a downstream side of the cooling section in a time series; a control direction determining step; When the upper side of the hot-rolled steel sheet has a positive value in the vertical direction, the temperature of the hot-rolled steel sheet is averaged over a period of one cycle or longer with respect to the waveform of the hot-rolled steel sheet in a field in which the fluctuation speed is a positive value. When the temperature is low, at least one of the direction in which the cooling and heat removal is reduced and the direction in which the cooling and heat removal in the lower portion are increased is determined as the control direction, and when the temperature of the hot-rolled steel sheet is higher than the average temperature, the foregoing At least one of the direction in which the upper heat removal heat is increased and the direction in which the lower cooling heat removal is reduced is determined as the aforementioned control direction, and In the field where the fluctuation speed is a negative value, when the temperature of the hot-rolled steel sheet is lower than the average temperature, at least one of a direction in which the upper cooling heat removal amount increases and a direction in which the lower surface cooling heat removal amount decreases is determined. In the control direction, when the temperature of the hot-rolled steel sheet is higher than the average temperature, at least one of the direction in which the cooling and heat removal is reduced and the direction in which the cooling and heat removal in the lower surface are increased are determined as the control direction; And a cooling and heat removal adjustment step of adjusting at least one of the upper surface cooling heat removal amount and the lower surface cooling heat removal amount of the hot-rolled steel sheet in the cooling section based on the control direction determined in the control direction determining step.

(9)上述(8)所揭露之熱軋鋼板冷卻方法中,前述 冷卻區間亦可沿前述熱軋鋼板之送板方向而分割成複數之分割冷卻區間,前述溫度測定步驟及前述變動速度測定步驟中,則就前述分割冷卻區間之邊界個別依時間序列而測定前述熱軋鋼板之溫度及變動速度,前述控制方向決定步驟中,則基於前述分割冷卻區間之邊界個別之前述熱軋鋼板之溫度及變動速度之測定結果,而就前述分割冷卻區間個別決定前述熱軋鋼板之上下面之冷卻除熱量之增減方向,前述冷卻除熱量調整步驟中,則基於已就前述分割冷卻區間個別而決定之前述控制方向進行回饋控制或前饋控制,以就前述分割冷卻區間個別調整前述熱軋鋼板之前述上面冷卻除熱量及前述下面冷卻除熱量之至少一方。 (9) In the method for cooling a hot-rolled steel sheet disclosed in the above (8), the aforementioned The cooling section may be divided into a plurality of divided cooling sections along the sheet feeding direction of the hot-rolled steel sheet, and in the temperature measuring step and the variable speed measuring step, the heat is measured in time series by the boundary of the divided cooling section. The temperature and the fluctuation speed of the rolled steel sheet, in the control direction determining step, the hot-rolled steel sheet is individually determined for the divided cooling section based on the measurement results of the temperature and the fluctuation speed of the hot-rolled steel sheet individually at the boundary of the divided cooling section In the cooling and heat removal adjustment step, the feedback control method or the feedforward control is performed based on the control direction determined by the individual divided cooling sections, respectively, in the cooling and de-heating adjustment step of the upper and lower sides, so as to separate the cooling sections At least one of the aforementioned upper cooling heat removal amount and the lower surface cooling heat removal amount of the hot-rolled steel sheet is adjusted.

(10)上述(9)所揭露之熱軋鋼板冷卻方法中,其中亦可進而包含以下步驟:測定步驟,就前述分割冷卻區間之邊界個別測定前述熱軋鋼板之前述傾斜度或前述送板速度;及,冷卻除熱量修正步驟,基於前述傾斜度或前述送板速度之測定結果,而修正前述分割冷卻區間個別之前述熱軋鋼板之前述上面冷卻除熱量及前述下面冷卻除熱量之至少一方。 (10) The method for cooling a hot-rolled steel sheet according to the above (9), further comprising the step of: measuring the inclination of the hot-rolled steel sheet or the sheet feeding speed of the boundary of the divided cooling section; And a cooling and heat removal correction step of correcting at least one of the upper cooling heat removal amount and the lower surface cooling heat removal amount of the hot-rolled steel sheet in the divided cooling section based on the measurement result of the inclination or the sheet feeding speed.

(11)上述(1)或(2)所揭露之熱軋鋼板冷卻方法中,亦可進而包含後冷卻步驟,係於前述冷卻區間之下游側進而冷卻前述熱軋鋼板,以使前述熱軋鋼板之溫度標準偏差在可容許之範圍內。 (11) The method for cooling a hot-rolled steel sheet according to the above (1) or (2), further comprising a post-cooling step of cooling the hot-rolled steel sheet on a downstream side of the cooling section to obtain the hot-rolled steel sheet The standard deviation of the temperature is within the allowable range.

(12)上述(1)或(2)所揭露之熱軋鋼板冷卻方法中,前述冷卻區間內之前述熱軋鋼板之送板速度亦可設在 550m/min以上至機械性極限速度以下之範圍內。 (12) In the method for cooling a hot-rolled steel sheet according to the above (1) or (2), the sheet feeding speed of the hot-rolled steel sheet in the cooling section may be set at Above 550m/min to below the mechanical limit speed.

(13)上述(1)或(2)所揭露之熱軋鋼板冷卻方法中,前述熱軋鋼板之拉伸強度亦可為800MPa以上。 (13) The method for cooling a hot-rolled steel sheet according to the above (1) or (2), wherein the hot-rolled steel sheet has a tensile strength of 800 MPa or more.

(14)上述(12)所揭露之熱軋鋼板冷卻方法中,前述精軋機亦可由複數之輥軋台所構成,本方法亦可更包含輔助冷卻步驟,係於前述複數之輥軋台彼此之間進行前述熱軋鋼板之輔助冷卻。 (14) In the method for cooling a hot-rolled steel sheet as disclosed in the above (12), the finishing mill may be composed of a plurality of rolling stations, and the method may further include an auxiliary cooling step, which is performed between the plurality of rolling stations Auxiliary cooling of the aforementioned hot rolled steel sheet is performed.

(15)上述(1)或(2)所揭露之熱軋鋼板冷卻方法中,前述冷卻區間中亦可設有包含可朝前述熱軋鋼板上面噴射冷卻水之複數集管之上側冷卻裝置,以及包含可朝前述熱軋鋼板下面噴射冷卻水之複數集管之下側冷卻裝置,前述上面冷卻除熱量及前述下面冷卻除熱量可藉前述各集管之開閉控制而進行調整。 (15) The method for cooling a hot-rolled steel sheet according to the above (1) or (2), wherein the cooling section may further include a plurality of header upper side cooling means including a cooling water sprayable on the hot-rolled steel sheet, and The lower header cooling device includes a plurality of headers that can spray cooling water toward the lower surface of the hot-rolled steel sheet, and the upper cooling heat removal and the lower cooling heat removal can be adjusted by opening and closing control of the respective headers.

(16)上述(1)或(2)所揭露之熱軋鋼板冷卻方法中,前述冷卻區間中亦可設有包含可朝前述熱軋鋼板上面噴射冷卻水之複數集管之上側冷卻裝置,以及包含可朝前述熱軋鋼板下面噴射冷卻水之複數集管之下側冷卻裝置,前述上面冷卻除熱量及前述下面冷卻除熱量可藉前述各集管之水量密度、壓力及水溫之至少一種之控制而進行調整。 (16) The method of cooling a hot-rolled steel sheet according to the above (1) or (2), wherein the cooling section may further include a plurality of header upper side cooling means including a cooling water sprayable on the hot-rolled steel sheet, and a plurality of header lower cooling devices capable of injecting cooling water under the hot-rolled steel sheet, wherein the upper cooling heat removal amount and the lower cooling heat removal amount are at least one of a water density, a pressure, and a water temperature of the respective headers. Adjust by control.

(17)上述(1)或(2)所揭露之熱軋鋼板冷卻方法中,前述冷卻區間中之冷卻亦可在前述熱軋鋼板之溫度為600℃以上之範圍內進行。 (17) In the method of cooling a hot-rolled steel sheet according to the above (1) or (2), the cooling in the cooling zone may be performed in a range in which the temperature of the hot-rolled steel sheet is 600 °C or higher.

本案發明人在熱軋鋼板之傾斜度及送板速度為 一定值之條件下,致力調查熱軋鋼板之上下面之導熱係數之比率之上下導熱係數比率X與熱軋鋼板之冷卻中或冷卻後之溫度標準偏差Y之相關關係後,已發現藉將上下導熱係數比率X控制成特定值,即可使溫度標準偏差Y最小化(即,可均一地冷卻熱軋鋼板)。 The inclination of the inventor of the present invention in the hot rolled steel plate and the plate feeding speed are Under certain conditions, after investigating the relationship between the ratio of the thermal conductivity of the upper and lower thermal conductivity of the hot-rolled steel sheet and the temperature standard deviation Y of the hot-rolled steel sheet during cooling or after cooling, it has been found that The thermal conductivity ratio X is controlled to a specific value to minimize the temperature standard deviation Y (i.e., the hot rolled steel sheet can be uniformly cooled).

因此,依據本發明,即可基於已預先實驗性地求出之熱軋鋼板之上下導熱係數比率X與溫度標準偏差Y之相關資料,而將可使溫度標準偏差Y為最小值Ymin之上下導熱係數比率X1設定成目標比率Xt,並控制熱軋鋼板之上面冷卻除熱量與下面冷卻除熱量之至少一方以使冷卻區間內之熱軋鋼板之上下導熱係數比率X與上述之目標比率Xt一致,故可均一地冷卻業經精軋機之熱軋而形成波形之熱軋鋼板。 Therefore, according to the present invention, it is possible to determine the thermal conductivity coefficient ratio X and the temperature standard deviation Y of the hot-rolled steel sheet which has been experimentally determined in advance, and to make the temperature standard deviation Y be the minimum value Ymin. The coefficient ratio X1 is set to the target ratio Xt, and controls at least one of the upper heat removal heat removal amount and the lower heat removal heat removal amount of the hot-rolled steel sheet so that the upper and lower thermal conductivity ratio X of the hot-rolled steel sheet in the cooling section coincides with the target ratio Xt described above. Therefore, it is possible to uniformly cool the hot-rolled steel sheet which has been subjected to hot rolling by a finishing mill to form a corrugated steel sheet.

1、2‧‧‧熱軋設備 1, 2‧‧‧ hot rolling equipment

11、111‧‧‧加熱爐 11, 111‧‧‧ heating furnace

12、112、201‧‧‧粗軋機 12, 112, 201‧‧‧ rough rolling mill

12a、112a‧‧‧工作軋輥 12a, 112a‧‧‧ work rolls

12b、112b‧‧‧四重式軋機 12b, 112b‧‧‧ quadruple mill

13、113、203‧‧‧精軋機 13, 113, 203‧‧‧ finishing mill

13a、113a‧‧‧精軋輥 13a, 113a‧‧‧ fine rolls

14、114、142、211‧‧‧冷卻裝置 14, 114, 142, 211‧‧‧ □ cooling device

14a、114a、142a‧‧‧上側冷卻裝置 14a, 114a, 142a‧‧‧ upper cooling unit

14b、114b、142b‧‧‧下側冷卻裝置 14b, 114b, 142b‧‧‧ lower cooling unit

15、115‧‧‧盤捲裝置 15, 115‧‧‧ coiling device

16、116‧‧‧寬度方向輥軋機 16, 116‧‧‧Width direction rolling mill

31、131、146‧‧‧冷卻口 31, 131, 146‧‧ ‧ cooling port

32、132、220‧‧‧輸送輥 32, 132, 220‧‧‧ conveyor rollers

40‧‧‧溫度計 40‧‧‧ thermometer

41‧‧‧形狀計 41‧‧‧ Shape meter

133‧‧‧護坦 133‧‧‧ Aunt

140、202a~202d‧‧‧輥軋台 140, 202a~202d‧‧‧Rolling table

212‧‧‧盤捲裝置 212‧‧‧ coiling device

A、B‧‧‧領域 A, B‧‧‧ fields

H‧‧‧熱軋鋼板 H‧‧‧Hot rolled steel plate

S‧‧‧鋼胚 S‧‧‧ steel embryo

Z1、Z2‧‧‧分割冷卻區間 Z1, Z2‧‧‧ split cooling interval

圖1係顯示本發明一實施形態之可實現熱軋鋼板冷卻方法之熱軋設備1之說明圖。 Fig. 1 is an explanatory view showing a hot rolling apparatus 1 capable of realizing a method of cooling a hot rolled steel sheet according to an embodiment of the present invention.

圖2係顯示設於熱軋設備1之冷卻裝置14之構造之概況之說明圖。 FIG. 2 is an explanatory view showing an outline of the configuration of the cooling device 14 provided in the hot rolling facility 1.

圖3係顯示在熱軋鋼板H之傾斜度與送板速度為一定值之條件下所求出之上下導熱係數比率X與溫度標準偏差Y之相關關係之圖表。 Fig. 3 is a graph showing the correlation between the upper and lower thermal conductivity ratios X and the temperature standard deviation Y obtained under the condition that the inclination of the hot-rolled steel sheet H and the sheet feeding speed are constant.

圖4係顯示自圖3所示之相關關係求出溫度標準偏差Y之最低點(最小值Ymin)之方法之說明圖。 Fig. 4 is an explanatory diagram showing a method of obtaining the lowest point (minimum value Ymin) of the temperature standard deviation Y from the correlation shown in Fig. 3.

圖5係顯示通常操作時之代表性之帶鋼之ROT內冷卻之熱軋鋼板H之溫度變動與傾斜度之關係之圖表,上側圖表顯 示對應與鋼捲先端之距離或定點經過時間之溫度變動,下側圖表則顯示對應與鋼捲先端之距離或定點經過時間之傾斜度。 Fig. 5 is a graph showing the relationship between the temperature variation and the inclination of the hot-rolled steel sheet H in the ROT of the representative steel strip in the usual operation, and the upper graph is shown. Indicates the temperature change corresponding to the distance from the tip of the coil or the elapsed time of the fixed point. The lower graph shows the slope corresponding to the distance from the tip of the coil or the elapsed time of the fixed point.

圖6係顯示通常操作時之代表性之帶鋼之ROT內冷卻之熱軋鋼板H之溫度變動與傾斜度之關係之圖表。 Fig. 6 is a graph showing the relationship between the temperature fluctuation and the inclination of the hot-rolled steel sheet H cooled in the ROT of the representative steel strip in the normal operation.

圖7係顯示熱軋鋼板H之變動速度在正值領域內對應熱軋鋼板H之平均溫度而降低熱軋鋼板H之溫度,變動速度在負值領域內而熱軋鋼板H之溫度升高時,減少上面冷卻除熱量並增加下面冷卻除熱量後之熱軋鋼板H之溫度變動與傾斜度之關係之圖表。另,熱軋鋼板H之波形之傾斜度係指以波形之振幅除以1周期量之輥軋方向之長度所得之值。 Fig. 7 is a view showing that the fluctuating speed of the hot-rolled steel sheet H is lower than the average temperature of the hot-rolled steel sheet H in the positive value field, and the temperature of the hot-rolled steel sheet H is lowered, and the fluctuation speed is in the negative value range and the temperature of the hot-rolled steel sheet H is raised. The graph of the relationship between the temperature change and the inclination of the hot-rolled steel sheet H after cooling and removing heat and increasing the heat removal and heat removal is reduced. Further, the inclination of the waveform of the hot-rolled steel sheet H means a value obtained by dividing the amplitude of the waveform by the length of the rolling direction of one cycle.

圖8係顯示熱軋鋼板H之變動速度在正值領域內對應熱軋鋼板H之平均溫度而降低熱軋鋼板H之溫度,變動速度在負值領域內而熱軋鋼板H之溫度升高後,增加上面冷卻除熱量並減少下面冷卻除熱量後之熱軋鋼板H之溫度變動與傾斜度之關係之圖表。 8 is a view showing that the fluctuating speed of the hot-rolled steel sheet H is lower than the average temperature of the hot-rolled steel sheet H in the positive value field, and the temperature of the hot-rolled steel sheet H is lowered, and the fluctuation speed is in the negative value range and the temperature of the hot-rolled steel sheet H is raised. A graph showing the relationship between the temperature change and the inclination of the hot-rolled steel sheet H after cooling and removing heat and reducing the heat removal and heat removal.

圖9係顯示在上下導熱係數比率X與送板速度為一定值之條件下所求出之熱軋鋼板H之傾斜度與溫度標準偏差Y之相關關係之圖表。 Fig. 9 is a graph showing the correlation between the inclination of the hot-rolled steel sheet H and the temperature standard deviation Y obtained under the condition that the upper and lower thermal conductivity ratio X and the sheet feeding speed are constant.

圖10係顯示就傾斜度之值不同之複數條件(但送板速度固定)個別而求出之上下導熱係數比率X與溫度標準偏差Y之相關關係之圖表。 Fig. 10 is a graph showing the correlation between the upper and lower thermal conductivity ratios X and the temperature standard deviation Y in terms of a plurality of conditions in which the values of the inclinations are different (but the plate feeding speed is fixed).

圖11係顯示在上下導熱係數比率X與傾斜度為一定值之條件下所求出之熱軋鋼板H之送板速度與溫度標準偏差 Y之相關關係之圖表。 Figure 11 shows the standard deviation of the plate feeding speed and temperature of the hot-rolled steel sheet H obtained under the condition that the upper and lower thermal conductivity ratio X and the inclination are constant. A chart of the relationship between Y.

圖12係顯示就送板速度之值不同之複數條件(但傾斜度固定)個別求出之上下導熱係數比率X與溫度標準偏差Y之相關關係之圖表。 Fig. 12 is a graph showing the correlation between the upper and lower thermal conductivity ratios X and the temperature standard deviation Y in a plurality of conditions (but the inclination is fixed) in which the values of the plate feed speeds are different.

圖13係顯示熱軋設備1之冷卻裝置14之周邊細節之說明圖。 Fig. 13 is an explanatory view showing details of the periphery of the cooling device 14 of the hot rolling facility 1.

圖14係顯示冷卻裝置14之變形例之說明圖。 FIG. 14 is an explanatory view showing a modification of the cooling device 14.

圖15係顯示熱軋鋼板H之板寬方向上已形成溫度標準偏差之狀態之說明圖。 Fig. 15 is an explanatory view showing a state in which the temperature standard deviation has been formed in the sheet width direction of the hot-rolled steel sheet H.

圖16係顯示另一實施形態之可實現熱軋鋼板H之冷卻方法之熱軋設備2之說明圖。 Fig. 16 is an explanatory view showing a hot rolling facility 2 which can realize a cooling method of the hot rolled steel sheet H according to another embodiment.

圖17係顯示熱軋設備2中配設之冷卻裝置114之構造之概況之說明圖。 Fig. 17 is an explanatory view showing an outline of the configuration of the cooling device 114 provided in the hot rolling facility 2.

圖18A係顯示熱軋鋼板H之最低點接觸輸送輥132之狀態之說明圖。 Fig. 18A is an explanatory view showing a state in which the lowest point of the hot-rolled steel sheet H contacts the conveying roller 132.

圖18B係顯示熱軋鋼板H之最低點接觸輸送輥132及護坦133之狀態之說明圖。 Fig. 18B is an explanatory view showing a state in which the lowest point of the hot-rolled steel sheet H contacts the conveying roller 132 and the protector 133.

圖19A係顯示熱軋鋼板H之送板速度為低速時之熱軋鋼板H之溫度之歷時變化之圖表。 Fig. 19A is a graph showing the temporal change of the temperature of the hot-rolled steel sheet H when the sheet feeding speed of the hot-rolled steel sheet H is low.

圖19B係顯示熱軋鋼板H之送板速度為高速時之熱軋鋼板H之溫度之歷時變化之圖表。 Fig. 19B is a graph showing the temporal change of the temperature of the hot-rolled steel sheet H when the sheet feeding speed of the hot-rolled steel sheet H is high.

圖20係可進行軋台間冷卻之精軋機113之說明圖。 Fig. 20 is an explanatory view of a finishing mill 113 capable of performing inter-rolling cooling.

圖21係顯示習知之熱軋鋼板H之製造方法之說明圖。 Fig. 21 is an explanatory view showing a manufacturing method of a conventional hot-rolled steel sheet H.

圖22係顯示習知之熱軋鋼板H之冷卻方法之說明圖。 Fig. 22 is an explanatory view showing a conventional cooling method of the hot-rolled steel sheet H.

用以實施發明之形態 Form for implementing the invention

以下,就諸如汽車及工業機械等所使用之用於冷卻熱軋鋼板之熱軋鋼板冷卻方法,參照圖示加以說明作為本發明之一實施形態。 Hereinafter, a method of cooling a hot-rolled steel sheet for cooling a hot-rolled steel sheet, such as an automobile or an industrial machine, will be described as an embodiment of the present invention with reference to the drawings.

圖1係模式地顯示本實施形態之可實現熱軋鋼板冷卻方法之熱軋設備1之例者。該熱軋設備1係目的在以軋輥上下夾持已加熱之鋼胚S而連續加以軋薄至最小1mm再加以盤捲之設備。 Fig. 1 is a view schematically showing an example of a hot rolling facility 1 which can realize a method of cooling a hot rolled steel sheet according to the present embodiment. The hot rolling equipment 1 is intended to be a device in which a heated steel slab S is held up and down by a roll and continuously rolled to a minimum of 1 mm and then coiled.

該熱軋設備1包含可加熱鋼胚S之加熱爐11、可朝寬度方向輥軋已於該加熱爐11中業經加熱之鋼胚S之寬度方向輥軋機16、可自上下方向輥軋已朝上述寬度方向經輥軋之鋼胚S而加以形成粗軋材之粗軋機12、可進而對粗軋材連續進行熱精軋至形成預定厚度之精軋機13、可藉冷卻水冷卻已藉該精軋機13而經熱精軋之熱軋鋼板H之冷卻裝置14、可將已藉冷卻裝置14而經冷卻之熱軋鋼板H捲成鋼捲狀之盤捲裝置15。 The hot rolling apparatus 1 includes a heating furnace 11 capable of heating the steel preform S, and a width direction rolling mill 16 capable of rolling the steel slab S which has been heated in the heating furnace 11 in the width direction, and can be rolled from the upper and lower directions. The rough rolling mill 12 for forming a rough-rolled product by rolling the steel slab S in the width direction, and further continuously hot-rolling the rough-rolled material to a finishing mill 13 having a predetermined thickness, which can be cooled by cooling water The cooling device 14 of the hot-rolled steel sheet H that has been hot-rolled by the rolling mill 13 can wind the hot-rolled steel sheet H that has been cooled by the cooling device 14 into a coil-like coiling device 15.

加熱爐11配設有可對經裝入口而自外部搬入之鋼胚S噴出火焰而加熱鋼胚S之側燃燒器、軸流燃燒器、爐頂燃燒器。已搬入加熱爐11中之鋼胚S則於形成在各區中之各加熱區內依序受加熱,進而於最終區內形成之均熱區中藉爐頂燃燒器而均勻加熱鋼胚S,以進行可在最適溫度下進行輸送所需之保溫處理。一旦結束加熱爐11之全部加熱處理,即朝加熱爐11外輸送鋼胚S,並接續進行粗軋機12之輥 軋製程。 The heating furnace 11 is provided with a side burner, an axial flow burner, and a top burner that can heat the steel slab S by ejecting a flame from a steel slab that is loaded from the outside through the loading port. The steel slabs S that have been moved into the heating furnace 11 are sequentially heated in the respective heating zones formed in the respective zones, and the steel slabs S are uniformly heated by the top burner in the soaking zone formed in the final zone. In order to carry out the heat treatment required for transport at the optimum temperature. Once the entire heat treatment of the heating furnace 11 is completed, the steel slab S is conveyed outside the heating furnace 11, and the rolls of the roughing mill 12 are successively carried out. Rolling process.

粗軋機12將就送入之鋼胚S使其通過橫跨複數軋台而配設之圓柱狀之旋轉軋輥之間隙。舉例言之,該粗軋機12可僅藉第1軋台中配設於上下方之工作軋輥12a而對鋼胚S進行熱軋以形成粗軋材。其次,藉工作軋輥與補強軋輥所構成之複數之四重式軋機12b進而對已通過上述工作軋輥12a之粗軋材連續進行輥軋。其結果,本粗軋製程結束時,粗軋材已輥軋成厚度30~60mm程度,再朝精軋機13加以輸送。 The roughing mill 12 will feed the steel slabs S through the gaps of the cylindrical rotating rolls disposed across the plurality of rolling stands. For example, the roughing mill 12 may hot-roll the steel slab S by only the work rolls 12a disposed in the upper and lower stages in the first rolling stand to form a rough rolled material. Next, the quadruple mill 12b composed of the work rolls and the reinforcing rolls is continuously rolled for the rough-rolled material that has passed through the work rolls 12a. As a result, at the end of the rough rolling pass, the rough rolled material is rolled to a thickness of about 30 to 60 mm, and then conveyed to the finishing mill 13.

精軋機13則對自粗軋機12送入之粗軋材進行精軋至其厚度為數mm程度為止。該等精軋機13係使粗軋材通過橫跨6~7個軋台而排列成上下一直線之精軋輥13a之間隙,而徐緩予以加壓。業經上述精軋機13之精軋之熱軋鋼板H則將藉後述之輸送輥32而送往冷卻裝置14。 The finishing mill 13 finish-rolls the rough-rolled material fed from the roughing mill 12 to a thickness of several mm. These finishing mills 13 are configured such that the rough-rolled material is arranged in a gap between the finishing rolls 13a of the upper and lower straight lines across 6 to 7 rolling stands, and is gradually pressurized. The hot-rolled steel sheet H subjected to the finish rolling of the finishing mill 13 is sent to the cooling device 14 by a conveying roller 32 which will be described later.

冷卻裝置14係用於對自精軋機13送入之熱軋鋼板H實施所謂層流冷卻之設備。本冷卻裝置14一如圖2所示,包含可對移動於滑出台之輸送輥32上之熱軋鋼板H上面自上側之冷卻口31噴射冷卻水之上側冷卻裝置14a,以及可對熱軋鋼板H下面自下側之冷卻口31噴射冷卻水之下側冷卻裝置14b。上側冷卻裝置14a及下側冷卻裝置14b個別設有複數個冷卻口31。 The cooling device 14 is a device for performing so-called laminar cooling on the hot-rolled steel sheet H fed from the finishing mill 13. As shown in FIG. 2, the cooling device 14 includes a cooling water upper side cooling device 14a for ejecting the upper surface of the hot-rolled steel sheet H on the conveying roller 32 of the sliding table, and a hot-rolled steel sheet. Below the H, the cooling water lower side cooling device 14b is sprayed from the lower side cooling port 31. The upper cooling device 14a and the lower cooling device 14b are individually provided with a plurality of cooling ports 31.

又,冷卻口31並連接冷卻集管(圖示省略)。上述冷卻口31之個數則決定上側冷卻裝置14a及下側冷卻裝置14b之冷卻能力。另,上述冷卻裝置14亦可構成上下分流層流(split laminar)、層流管流、噴霧冷卻等之至少一種。又,藉上述冷卻裝置14而冷卻熱軋鋼板H之區間相當於本發明之冷卻區間。 Further, the cooling port 31 is connected to a cooling header (not shown). The number of the cooling ports 31 determines the cooling capacity of the upper cooling device 14a and the lower cooling device 14b. In addition, the cooling device 14 may also constitute an upper and lower split flow (split) At least one of laminar), laminar flow, spray cooling, and the like. Further, the section in which the hot-rolled steel sheet H is cooled by the cooling device 14 corresponds to the cooling section of the present invention.

盤捲裝置15則如圖1所示,可在預定之盤捲溫度下盤捲已藉冷卻裝置14而冷卻之熱軋鋼板H。已藉盤捲裝置15而捲成鋼捲狀之熱軋鋼板H將輸送至熱軋設備1外。 As shown in Fig. 1, the coiling device 15 can wind the hot-rolled steel sheet H which has been cooled by the cooling device 14 at a predetermined coil temperature. The hot-rolled steel sheet H which has been wound into a coil shape by the coiling device 15 is sent to the outside of the hot rolling apparatus 1.

以下,說明可藉構成如上之熱軋設備1而實現之本實施形態之熱軋鋼板冷卻方法。 Hereinafter, a method of cooling a hot-rolled steel sheet according to the present embodiment which can be realized by the hot rolling facility 1 as described above will be described.

另,以下之說明中,業經精軋機13之熱軋之熱軋鋼板H一如圖22所示,於其輥軋方向上形成有表面高度(波高)變動之波形。且,以下之說明中,將於熱軋鋼板H之冷卻時忽略上述熱軋鋼板H上殘留之積水之影響。實際上,本案發明人調查之結果,已知熱軋鋼板H上殘留之積水之影響幾乎不存在。 In the following description, as shown in Fig. 22, the hot-rolled steel sheet H which has been hot-rolled by the finishing mill 13 has a waveform in which the surface height (wave height) fluctuates in the rolling direction. Further, in the following description, the influence of the accumulated water remaining on the hot-rolled steel sheet H is ignored in the cooling of the hot-rolled steel sheet H. Actually, as a result of investigation by the inventors of the present invention, it is known that the influence of accumulated water remaining on the hot-rolled steel sheet H hardly exists.

本實施形態之熱軋鋼板冷卻方法包含目標比率設定步驟、冷卻控制步驟之2製程。 The hot-rolled steel sheet cooling method of the present embodiment includes a target ratio setting step and a cooling control step.

細節將留待後述,但目標比率設定步驟中,將基於已預先實驗性地在熱軋鋼板H之傾斜度及送板速度為一定值之條件下預先求出之代表熱軋鋼板H之上下面之導熱係數之比率之上下導熱係數比率X與熱軋鋼板H之冷卻中或冷卻後之溫度標準偏差Y之相關關係之相關資料,而將可使溫度標準偏差Y為最小值Ymin之上下導熱係數比率X1設為目標比率Xt。 The details will be described later, but in the target ratio setting step, the upper portion of the representative hot-rolled steel sheet H is obtained in advance based on the experimentally determined inclination of the hot-rolled steel sheet H and the sheet feeding speed. The ratio of the thermal conductivity coefficient above the thermal conductivity coefficient ratio X to the correlation between the temperature standard deviation Y of the hot-rolled steel sheet H during cooling or after cooling, and the temperature standard deviation Y is the minimum thermal conductivity ratio above the minimum Ymin X1 is set to the target ratio Xt.

且,冷卻控制步驟中,將控制冷卻區間內之熱軋鋼板H 之上面冷卻除熱量與下面冷卻除熱量之至少一方,以使冷卻區間(藉冷卻裝置14而冷卻熱軋鋼板H之區間)內之熱軋鋼板H之上下導熱係數比率X與上述之目標比率Xt一致。 And, in the cooling control step, the hot-rolled steel sheet H in the cooling section is controlled. The heat transfer coefficient ratio X of the hot-rolled steel sheet H in the cooling section (the section where the hot-rolled steel sheet H is cooled by the cooling device 14) and the target ratio Xt described above are at least one of the cooling heat removal heat and the lower heat removal heat removal. Consistent.

上述目標比率設定步驟中使用之相關資料係在實際操作前(實際製造作為產品之熱軋鋼板H之前)利用熱軋設備1而預先實驗性地求出者。以下,即詳細說明目標比率設定步驟所使用之相關資料之求出方法。 The relevant data used in the target ratio setting step described above is experimentally determined in advance by the hot rolling facility 1 before actual operation (before actual production of the hot-rolled steel sheet H as a product). Hereinafter, the method of determining the relevant data used in the target ratio setting step will be described in detail.

首先,在藉冷卻裝置14冷卻熱軋鋼板H前,預先分別調整冷卻裝置14之上側冷卻裝置14a之冷卻能力(上側冷卻能力)與下側冷卻裝置14b之冷卻能力(下側冷卻能力)。該等上側冷卻能力與下側冷卻能力分別採用藉上側冷卻裝置14a而冷卻之熱軋鋼板H上面之導熱係數,以及藉下側冷卻裝置14b而冷卻之熱軋鋼板H下面之導熱係數而進行調整。 First, before cooling the hot-rolled steel sheet H by the cooling device 14, the cooling capacity (upper cooling capacity) of the upper side cooling device 14a of the cooling device 14 and the cooling capacity (lower cooling capacity) of the lower side cooling device 14b are adjusted in advance. The upper side cooling capacity and the lower side cooling capacity are adjusted by using the thermal conductivity of the hot-rolled steel sheet H cooled by the upper side cooling device 14a and the thermal conductivity of the hot-rolled steel sheet H cooled by the lower side cooling device 14b. .

在此,說明熱軋鋼板H之上面與下面之導熱係數之算出方法。導熱係數係來自單位面積之各單位時間之冷卻除熱量(熱能)除以被導熱體與熱媒之溫差所得之值(導熱係數=冷卻除熱量/溫差)。此之溫差則係藉冷卻裝置14之入口側之溫度計測得之熱軋鋼板H之溫度與冷卻裝置14所使用之冷卻水之溫度之差。 Here, a method of calculating the thermal conductivity of the upper surface and the lower surface of the hot-rolled steel sheet H will be described. The thermal conductivity is derived from the cooling and heat removal (thermal energy) per unit time per unit area divided by the temperature difference between the thermal conductor and the heat medium (thermal conductivity = cooling removal heat / temperature difference). The temperature difference is the difference between the temperature of the hot rolled steel sheet H measured by the thermometer on the inlet side of the cooling device 14 and the temperature of the cooling water used by the cooling device 14.

又,冷卻除熱量係熱軋鋼板H之溫差與比熱、質量個別相乘所得之值(冷卻除熱量=溫差×比熱×質量)。即,冷卻除熱量係冷卻裝置14中之熱軋鋼板H之冷卻除熱量,而為冷卻裝置14之入口側之溫度計與出口側之溫度計分別測得之熱軋鋼板H之溫度之差、熱軋鋼板H之比熱、藉冷卻裝置14而 冷卻之熱軋鋼板H之質量個別相乘所得之值。 Further, the value of the temperature difference between the cooling and heat removal hot-rolled steel sheets H and the specific heat and mass are individually (cooling heat removal = temperature difference × specific heat × mass). That is, the cooling and heat removal of the hot-rolled steel sheet H in the heat-removing cooling device 14 is cooled, and the difference between the temperature of the hot-rolled steel sheet H measured by the thermometer on the inlet side of the cooling device 14 and the thermometer on the outlet side is hot rolling. The specific heat of the steel plate H, by the cooling device 14 The value obtained by individually multiplying the mass of the cooled hot-rolled steel sheet H.

如上而算出之熱軋鋼板H之導熱係數則分為熱軋鋼板H之上面與下面之導熱係數。該等上面與下面之導熱係數係採用諸如預先求出如下之比率而算出者。 The thermal conductivity of the hot-rolled steel sheet H calculated as described above is divided into the thermal conductivity of the upper surface and the lower surface of the hot-rolled steel sheet H. These upper and lower thermal conductivity coefficients are calculated by, for example, predetermining the ratios as follows.

即,測定僅藉上側冷卻裝置14a冷卻熱軋鋼板H時之熱軋鋼板H之導熱係數,以及僅藉下側冷卻裝置14b冷卻熱軋鋼板H時之熱軋鋼板H之導熱係數。 In other words, the thermal conductivity of the hot-rolled steel sheet H when the hot-rolled steel sheet H is cooled by the upper cooling device 14a and the thermal conductivity of the hot-rolled steel sheet H when the hot-rolled steel sheet H is cooled by the lower cooling device 14b are measured.

此時,則使來自上側冷卻裝置14a之冷卻水量與來自下側冷卻裝置14b之冷卻水量相同。業經測定之使用上側冷卻裝置14a時之導熱係數與使用下側冷卻裝置14b時之導熱係數之比率之倒數即為後述之上下導熱係數比率X為“1”時之上側冷卻裝置14a之冷卻水量與下側冷卻裝置14b之冷卻水量之上下比率。 At this time, the amount of cooling water from the upper side cooling device 14a is made equal to the amount of cooling water from the lower side cooling device 14b. The reciprocal of the ratio of the thermal conductivity when the upper side cooling device 14a is used to the thermal conductivity when the lower side cooling device 14b is used is the amount of cooling water of the upper side cooling device 14a when the upper and lower thermal conductivity ratio X is "1". The amount of cooling water of the lower side cooling device 14b is above the ratio.

其次,如上而算出之冷卻水量之上下比率再乘以冷卻熱軋鋼板H時之上側冷卻裝置14a之冷卻水量或下側冷卻裝置14b之冷卻水量,即算出上述熱軋鋼板H之上面與下面之導熱係數之比率(上下導熱係數比率X)。 Then, the upper and lower ratios of the amount of cooling water calculated as described above are multiplied by the amount of cooling water of the upper side cooling device 14a or the amount of cooling water of the lower side cooling device 14b when the hot rolled steel sheet H is cooled, that is, the upper surface and the lower surface of the hot rolled steel sheet H are calculated. The ratio of thermal conductivity (upper and lower thermal conductivity ratio X).

又,上述說明雖採用僅藉上側冷卻裝置14a與僅藉下側冷卻裝置14b而冷卻之熱軋鋼板H之導熱係數,但亦可採用藉上側冷卻裝置14a與下側冷卻裝置14b之雙方而冷卻之熱軋鋼板H之導熱係數。即,亦可測定上側冷卻裝置14a與下側冷卻裝置14b之冷卻水量改變後之熱軋鋼板H之導熱係數,並採用該導熱係數之比率而算出熱軋鋼板H之上面與下面之導熱係數之比率。 Further, in the above description, the thermal conductivity of the hot-rolled steel sheet H cooled only by the upper side cooling device 14a and the lower side cooling device 14b is used, but cooling by both the upper side cooling device 14a and the lower side cooling device 14b may be employed. The thermal conductivity of the hot rolled steel sheet H. In other words, the thermal conductivity of the hot-rolled steel sheet H after the amount of cooling water of the upper cooling device 14a and the lower cooling device 14b is changed can be measured, and the thermal conductivity of the upper and lower surfaces of the hot-rolled steel sheet H can be calculated by using the ratio of the thermal conductivity. ratio.

如上所述,算出熱軋鋼板H之導熱係數,並基於熱軋鋼板H之上面與下面之導熱係數之上述比率(上下導熱係數比率X),即可算出熱軋鋼板H之上面與下面之導熱係數。 As described above, the thermal conductivity of the hot-rolled steel sheet H is calculated, and based on the above ratio of the thermal conductivity of the hot-rolled steel sheet H to the lower surface (the upper and lower thermal conductivity ratio X), the heat conduction between the upper surface and the lower surface of the hot-rolled steel sheet H can be calculated. coefficient.

其次,使用上述熱軋鋼板H之上下導熱係數比率X,並基於圖3而分別調整上側冷卻裝置14a與下側冷卻裝置14b之冷卻能力。圖3之橫軸代表熱軋鋼板H上面之平均導熱係數與下面之平均導熱係數之比(即,意義同於上下導熱係數比率X),縱軸代表熱軋鋼板H之輥軋方向上之最大溫度與最小溫度之溫度之標準偏差(溫度標準偏差Y。) Next, using the above-described hot-rolled steel sheet H upper and lower thermal conductivity ratio X, the cooling capacities of the upper side cooling device 14a and the lower side cooling device 14b are adjusted based on Fig. 3, respectively. The horizontal axis of Fig. 3 represents the ratio of the average thermal conductivity of the hot-rolled steel sheet H to the average thermal conductivity below (i.e., the same as the upper and lower thermal conductivity ratio X), and the vertical axis represents the maximum rolling direction of the hot-rolled steel sheet H. Standard deviation of temperature from minimum temperature (temperature standard deviation Y.)

又,圖3係顯示在熱軋鋼板H之波形之傾斜度與熱軋鋼板H之送板速度為一定值之條件下,調整上側冷卻裝置14a與下側冷卻裝置14b之冷卻能力而改變熱軋鋼板H之上下導熱係數比率X,同時實測冷卻後之熱軋鋼板H之溫度標準偏差Y所得之上下導熱係數比率X與溫度標準偏差Y之相關關係之資料(相關資料)。 Moreover, FIG. 3 shows that the cooling capacity of the upper side cooling device 14a and the lower side cooling device 14b is adjusted to change the hot rolling under the condition that the inclination of the waveform of the hot-rolled steel sheet H and the sheet feeding speed of the hot-rolled steel sheet H are constant. The ratio of the thermal conductivity ratio X above the steel sheet H, and the correlation between the thermal conductivity ratio X of the hot-rolled steel sheet H after cooling and the temperature standard deviation Y (relevant data).

參照圖3,則可知溫度標準偏差Y與上下導熱係數比率X之相關關係在上下導熱係數比率X為“1”時可使溫度標準偏差Y為最小值Ymin之V字狀之關係。 Referring to Fig. 3, it is understood that the correlation between the temperature standard deviation Y and the upper and lower thermal conductivity ratio X is such that the temperature standard deviation Y is a V-shaped relationship of the minimum value Ymin when the upper and lower thermal conductivity ratio X is "1".

另,熱軋鋼板H之波形之傾斜度係波形之振幅除以1周期量之輥軋方向上之長度所得之值。圖3係在設定熱軋鋼板H之傾斜度為2%,並設定送板速度為600m/min(10m/sac)之條件下所算得之上下導熱係數比率X與溫度標準偏差Y之相關資料。溫度標準偏差Y亦可在熱軋鋼板H之冷卻中測 定,或在冷卻後測定。又,圖3中熱軋鋼板H之目標冷卻溫度係600℃以上之溫度,諸如800℃。 Further, the inclination of the waveform of the hot-rolled steel sheet H is the value obtained by dividing the amplitude of the waveform by the length in the rolling direction of one cycle. Fig. 3 shows the correlation between the upper thermal conductivity ratio X and the temperature standard deviation Y under the condition that the inclination of the hot-rolled steel sheet H is set to 2% and the sheet feeding speed is set to 600 m/min (10 m/sac). The temperature standard deviation Y can also be measured in the cooling of hot rolled steel sheet H Determined, or measured after cooling. Further, the target cooling temperature of the hot-rolled steel sheet H in Fig. 3 is a temperature of 600 ° C or higher, such as 800 ° C.

目標比率設定步驟係如上而基於預先實驗性地求出之相關資料,而將可使溫度標準偏差Y為最小值Ymin之上下導熱係數比率X設為目標比率Xt。上述相關資料亦可準備成以表格(表之形式)顯示上下導熱係數比率X與溫度標準偏差Y之相關關係之資料(表格資料),或準備成以數式(諸如迴歸公式)顯示上下導熱係數比率X與溫度標準偏差Y之相關關係之資料。 The target ratio setting step is based on the above-described experimentally obtained correlation data, and the temperature standard deviation Y is set to the minimum value Ymin and the thermal conductivity ratio X is set to the target ratio Xt. The above related data may also be prepared to display the correlation between the upper and lower thermal conductivity ratio X and the temperature standard deviation Y in a table (form form) (form table data), or to prepare the upper and lower thermal conductivity by a numerical formula (such as a regression formula). Information on the relationship between the ratio X and the temperature standard deviation Y.

舉例言之,相關資料準備成以迴歸公式顯示上下導熱係數比率X與溫度標準偏差Y之相關關係之資料時,圖3所示之V字形線係夾隔谷底部而於兩側大致繪成直線狀,故亦可就該線進行直線迴歸而導出迴歸公式。若加以假設為線性分佈,則可減少藉受測材料進行確認之次數及計算預測所需之校準之次數。 For example, when the relevant data is prepared to display the correlation between the upper and lower thermal conductivity ratios X and the temperature standard deviation Y in a regression formula, the V-shaped line shown in FIG. 3 is sandwiched by the bottom of the valley and is roughly drawn on both sides. It is also possible to derive a regression formula for linear regression of the line. If it is assumed to be a linear distribution, the number of times of confirmation by the material to be tested and the number of calibrations required to calculate the prediction can be reduced.

因此,舉例言之,可採用一般周知之搜尋演算法之二分法、黃金分割法、隨機搜尋等各種方法求出溫度標準偏差Y之最小值Ymin。如此,即可基於圖3所示之相關資料而導出可使熱軋鋼板H之溫度標準偏差Y為最小值Ymin之上下導熱係數比率X1。又,在此,可於夾隔平均導熱係數在上下側均相等之點之兩側上分別預先求出對應上下導熱係數比率X之熱軋鋼板H之輥軋方向之溫度標準偏差Y之迴歸公式。 Therefore, for example, the minimum value Ymin of the temperature standard deviation Y can be obtained by various methods such as the dichotomy of the commonly known search algorithm, the golden section method, and the random search. Thus, based on the related data shown in FIG. 3, the temperature standard deviation Y of the hot-rolled steel sheet H can be derived as the minimum thermal conductivity ratio X1 above the minimum value Ymin. Here, the regression formula of the temperature standard deviation Y of the rolling direction of the hot-rolled steel sheet H corresponding to the upper and lower thermal conductivity ratios X can be obtained in advance on both sides of the point where the average thermal conductivity is equal to the upper and lower sides. .

以下,即採用上述之二分法而說明用於求出熱軋 鋼板H之溫度標準偏差Y之最小值Ymin之方法。 Hereinafter, the above-described dichotomy is used to describe the hot rolling. The method of the minimum value Ymin of the temperature standard deviation Y of the steel sheet H.

圖4係顯示可繪出夾隔溫度標準偏差Y之最小值Ymin而互異之回歸線之標準情形。如該圖4所示,首先,分別選出業經實測之a點、b點、a點與b點之中點之c點之溫度標準偏差Ya、Yb、Yc。另,a點與b點之中點係指具有a點之上下導熱係數比率Xa與b點之上下導熱係數比率Xb之間之值之c點,以下亦同。其次,則判斷溫度標準偏差Yc近似Ya或Yb之何者之值。本實施形態中,Yc近似Ya。 Fig. 4 is a view showing a standard case in which the regression line of the standard deviation Y of the temperature difference Y is different and the difference is different. As shown in FIG. 4, first, the temperature standard deviations Ya, Yb, and Yc of the point c of the point a, the point b, the point a, and the point b are measured. In addition, the point a between point a and point b means the point c having the value of the thermal conductivity ratio Xa above the point a and the ratio of the thermal conductivity coefficient Xb above the point b, the same applies hereinafter. Next, it is judged whether the temperature standard deviation Yc approximates the value of Ya or Yb. In the present embodiment, Yc approximates Ya.

其次,選出a點與c點之中點之d點之溫度標準偏差Yd。然後,判斷溫度標準偏差Yd近似Ya或Yc之何者之值。本實施形態中,Yd近似Yc。 Next, the temperature standard deviation Yd of the point d of the point between the point a and the point c is selected. Then, it is judged whether the temperature standard deviation Yd is approximately the value of Ya or Yc. In the present embodiment, Yd approximates Yc.

接著,選出c點與d點之中點之e點之溫度標準偏差Ye。然後,判斷溫度標準偏差Ye近似Yc或Yd之何者之值。本實施形態中,Ye近似Yd。 Next, the temperature standard deviation Ye of the point e between the point c and the point d is selected. Then, it is judged whether the temperature standard deviation Ye approximates the value of Yc or Yd. In the present embodiment, Ye approximates Yd.

重複進行上述演算,而界定熱軋鋼板H之溫度標準偏差Y之最低點f(最小值Ymin)。另,為界定實用之最低點f,上述演算進行諸如5次程度即可。又,亦可將搜尋對象之上下導熱係數比率X之範圍分割成10個部分,並在個別範圍內進行上述之演算以界定最低點f。 The above calculation is repeated to define the lowest point f (minimum value Ymin) of the temperature standard deviation Y of the hot-rolled steel sheet H. In addition, in order to define the practical minimum point f, the above calculation may be performed for five times. Alternatively, the range of the thermal conductivity ratio X above and below the search object may be divided into 10 parts, and the above calculation may be performed in an individual range to define the lowest point f.

又,亦可採用所謂牛頓法而校準上下導熱係數比率X。此時,亦可採用上述之迴歸公式,而求出對應實際之溫度標準偏差Y之值之上下導熱係數比率X與可使溫度標準偏差Y為零之上下導熱係數比率X之偏差量,並使用上述偏差量而修正冷卻熱軋鋼板H時之上下導熱係數比率X。 Further, the upper and lower thermal conductivity ratios X can be calibrated by the so-called Newton method. At this time, the regression formula described above may be used, and the ratio of the thermal conductivity ratio X above the value corresponding to the actual temperature standard deviation Y to the thermal conductivity ratio X above the temperature standard deviation Y may be obtained and used. The above-described amount of deviation is used to correct the upper and lower thermal conductivity ratios X when the hot-rolled steel sheet H is cooled.

如上所述,即可導出可使熱軋鋼板H之溫度標準偏差Y為最小值Ymin之上下導熱係數比率X1(圖4中之Xf)。又,呈V字狀之溫度標準偏差Y與上下導熱係數比率X之關係,則可就其兩側區分而藉最小平方法等分別輕易求出迴歸函數。 As described above, the temperature standard deviation Y of the hot-rolled steel sheet H can be derived as the minimum thermal conductivity ratio X1 (Xf in Fig. 4) above the minimum value Ymin. Further, in the relationship between the V-shaped temperature standard deviation Y and the upper and lower thermal conductivity ratio X, the regression function can be easily obtained by the least square method or the like for the two sides.

其次,參照圖3,可使熱軋鋼板H之溫度標準偏差Y為最小值Ymin之上下導熱係數比率X1為“1”。因此,求得圖3所示之相關資料後,為使溫度標準偏差Y為最小,即,為均一地冷卻熱軋鋼板H,將於實際操作時之目標比率設定步驟中將目標比率Xt設為“1”。 Next, referring to Fig. 3, the temperature standard deviation Y of the hot-rolled steel sheet H can be set to "1" above and below the minimum value Ymin. Therefore, after obtaining the relevant data shown in FIG. 3, in order to minimize the temperature standard deviation Y, that is, to uniformly cool the hot-rolled steel sheet H, the target ratio Xt is set in the target ratio setting step in actual operation. "1".

接著,冷卻控制步驟中,則控制冷卻區間內之熱軋鋼板H之上面冷卻除熱量與下面冷卻除熱量之至少一方,以使冷卻區間內之熱軋鋼板H之上下導熱係數比率X與上述之目標比率Xt(即“1”)一致。 Next, in the cooling control step, at least one of the upper surface heat removal heat removal amount and the lower heat removal heat removal amount of the hot-rolled steel sheet H in the cooling section is controlled so that the thermal conductivity ratio X of the hot-rolled steel sheet H in the cooling section is higher than the above The target ratio Xt (ie "1") is consistent.

具體而言,為使冷卻區間內之熱軋鋼板H之上下導熱係數比率X與目標比率Xt(即“1”)一致,舉例言之,可將上側冷卻裝置14a之冷卻能力與下側冷卻裝置14b之冷卻能力調整成相同,而使熱軋鋼板H之上面冷卻除熱量與下面冷卻除熱量相同。 Specifically, in order to make the upper thermal conductivity ratio X of the hot-rolled steel sheet H in the cooling section coincide with the target ratio Xt (ie, “1”), for example, the cooling capacity of the upper cooling device 14a and the lower cooling device can be used. The cooling capacity of 14b is adjusted to be the same, and the heat removal and heat removal of the hot-rolled steel sheet H is the same as the cooling and heat removal below.

表1即顯示圖3所示之相關資料(即上下導熱係數比率X與溫度標準偏差Y之相關關係)與自各溫度標準偏差Y減去最小值Ymin(=2.3℃)後之值(與最小值間之標準偏差之差分),以及各溫度標準偏差Y之評價。 Table 1 shows the relevant data shown in Figure 3 (ie, the correlation between the upper and lower thermal conductivity ratio X and the temperature standard deviation Y) and the value from the temperature standard deviation Y minus the minimum value Ymin (= 2.3 ° C) (and the minimum value) The difference between the standard deviations between the two, and the evaluation of the temperature standard deviation Y.

表1中之上下導熱係數比率X係分子為熱軋鋼板H上面 之導熱係數,分母為熱軋鋼板H下面之導熱係數者。且,表1中之評價(關於上下導熱係數比率X之條件之評價)則設定使溫度標準偏差Y為最小值Ymin之條件為“A”,並設定後述與最小值間之標準偏差之差分為10℃以內即適於操作之條件為“B”,且設定用於進行嘗試錯誤以求得上述迴歸公式之條件為“C”。其次,參照表1,評價亦為“A”,即,可使熱軋鋼板H之溫度標準偏差Y為最小值Ymin之上下導熱係數比率X1為“1”。 In Table 1, the thermal conductivity ratio X system molecule is the upper surface of the hot rolled steel sheet H The thermal conductivity and the denominator are the thermal conductivity of the hot rolled steel sheet H. Further, in the evaluation in Table 1 (evaluation of the condition of the upper and lower thermal conductivity ratio X), the condition that the temperature standard deviation Y is the minimum value Ymin is set to "A", and the difference between the standard deviation between the lower and lower values is set as The condition suitable for operation within 10 ° C is "B", and the condition for making an attempt error to obtain the above regression formula is "C". Next, referring to Table 1, the evaluation is also "A", that is, the temperature standard deviation Y of the hot-rolled steel sheet H is the minimum value Ymin and the thermal conductivity ratio X1 is "1".

另,若將熱軋鋼板H之溫度標準偏差Y至少控制在最小值Ymin至最小值Ymin+10℃以內之範圍內,則可將降伏應力、拉伸強度等之偏差控制在製造容許範圍內,而可謂可均一地冷卻熱軋鋼板H。即,上述之目標比率設定步驟中,亦可基於預先實驗性地算出之相關資料,而將可將溫度標準偏差Y控制在最小值Y至最小值Ymin+10℃以內之範圍內之上下導熱係數比率X設為目標比率Xt。 In addition, if the temperature standard deviation Y of the hot-rolled steel sheet H is controlled within at least the minimum value Ymin to the minimum value Ymin + 10 ° C, the deviation of the relief stress, the tensile strength, and the like can be controlled within the manufacturing tolerance range. It can be said that the hot rolled steel sheet H can be uniformly cooled. That is, in the target ratio setting step described above, the temperature standard deviation Y may be controlled within a range from the minimum value Y to the minimum value Ymin + 10 ° C based on the correlation data experimentally calculated in advance. The ratio X is set to the target ratio Xt.

另,熱軋鋼板H之溫度測定存在各種干擾,故嚴格而言,熱軋鋼板H之最小值Ymin可能不為零。因此,為消除上述干擾之影響,而將製造容許範圍設在熱軋鋼板H之溫度標準偏差Y為最小值Ymin至最小值Ymin+10℃以內之範圍內。 Further, there are various disturbances in the temperature measurement of the hot-rolled steel sheet H, so strictly speaking, the minimum value Ymin of the hot-rolled steel sheet H may not be zero. Therefore, in order to eliminate the influence of the above interference, the manufacturing allowable range is set within the range of the temperature standard deviation Y of the hot-rolled steel sheet H from the minimum value Ymin to the minimum value Ymin + 10 °C.

為將溫度標準偏差Y控制在最小值Ymin至最小值Ymin+10℃以內之範圍內,在圖3或圖4中,可自溫度標準偏差Y為最小值Ymin+10℃之縱軸上之點朝橫軸方向繪出直線,並求出該直線與V字曲線之兩側2條之回歸線之2個交點,而就該等2交點間之上下導熱係數比率X設定目標比率Xt。另,表1中,將評價為“B”之上下導熱係數比率X設為目標比率Xt,則可將溫度標準偏差Y控制在最小值Ymin至最小值Ymin+10℃以內之範圍內。 In order to control the temperature standard deviation Y within the range from the minimum value Ymin to the minimum value Ymin + 10 ° C, in FIG. 3 or FIG. 4, the point on the vertical axis from the temperature standard deviation Y is the minimum value Ymin + 10 ° C A straight line is drawn in the direction of the horizontal axis, and two intersections of the straight line and the two regression lines on both sides of the V-shaped curve are obtained, and the target ratio Xt is set in the upper thermal conductivity ratio X between the two intersections. In addition, in Table 1, when the thermal conductivity ratio X above the "B" is set as the target ratio Xt, the temperature standard deviation Y can be controlled within the range from the minimum value Ymin to the minimum value Ymin + 10 °C.

又,為使上下導熱係數比率X與目標比率Xt一致,操作上側冷卻裝置14a與下側冷卻裝置14b之至少一方之冷卻水量密度最為簡易。因此,諸如圖3及圖4中,亦可將橫軸之值讀為上下水量密度比,而於夾隔平均導熱係數在上下側均相等之點之兩側上求出對應水量密度之上下之比率之熱軋鋼板H之溫度標準偏差Y之迴歸公式。但,平均導熱係數在上下側均相等之點非必為冷卻水量密度在上下側均相等之點,故可略為廣泛地進行測試以求出迴歸公式。 Further, in order to match the upper and lower thermal conductivity ratio X with the target ratio Xt, it is most convenient to operate at least one of the upper cooling device 14a and the lower cooling device 14b. Therefore, for example, in FIG. 3 and FIG. 4, the value of the horizontal axis can also be read as the upper and lower water volume density ratio, and the corresponding water amount density can be obtained on both sides of the point where the average thermal conductivity of the sandwich is equal on the upper and lower sides. The regression formula of the temperature standard deviation Y of the ratio of the hot-rolled steel sheet H. However, the point where the average thermal conductivity is equal on both the upper and lower sides is not necessarily the point at which the cooling water density is equal on the upper and lower sides, so that the test can be performed extensively to obtain the regression formula.

又,實際操作時,可能因製造條件之變更而使傾斜度及送板速度之至少一方之值改變。一旦傾斜度及送板速度之至少一方之值改變,上下導熱係數比率X與溫度標準 偏差Y之相關關係亦將改變。因此,亦可就傾斜度及送板速度之值不同之複數條件個別預備上述之相關資料,並於目標比率設定步驟中,基於該等複數之相關資料內對應實際操作時之傾斜度及送板速度之實測值之相關資料而設定目標比率Xt。藉此,即可進行適用於實際操作時之製造條件之均一冷卻。 Further, at the time of actual operation, the value of at least one of the inclination and the plate feeding speed may be changed due to the change of the manufacturing conditions. Once the value of at least one of the inclination and the feed speed changes, the upper and lower thermal conductivity ratio X and the temperature standard The correlation of the deviation Y will also change. Therefore, the related data may be separately prepared for a plurality of conditions in which the values of the inclination and the plate feeding speed are different, and in the target ratio setting step, the inclination of the actual operation and the feeding plate are based on the relevant data of the plural numbers. The target ratio Xt is set based on the actual measured value of the speed. Thereby, uniform cooling suitable for the manufacturing conditions at the time of actual operation can be performed.

在此,本案發明人等人致力檢討為均一地冷卻熱軋鋼板H,而調整上側冷卻裝置14a與下側冷卻裝置14b之冷卻能力(控制熱軋鋼板H之上面冷卻除熱量與下面冷卻除熱量)之結果,進而有所發現如下。 Here, the inventors of the present invention have made an effort to review the cooling of the hot-rolled steel sheet H uniformly, and adjust the cooling capacity of the upper side cooling device 14a and the lower side cooling device 14b (control the heat-removing heat removal of the hot-rolled steel sheet H and the cooling and heat removal below) The results are further found as follows.

本案發明人等人就熱軋鋼板H已形成波形之狀態下之冷卻所致生之溫度標準偏差Y之特徵加以致力反覆檢討之結果,發現了以下事實。 The inventors of the present invention have made a review of the characteristics of the temperature standard deviation Y caused by the cooling in the state in which the hot-rolled steel sheet H has been formed into a waveform, and found the following facts.

一般而言,實際操作時,藉盤捲裝置15而盤捲熱軋鋼板H,必須將熱軋鋼板H之溫度控制為預定之目標溫度(適於進行盤捲之溫度)以維持熱軋鋼板H之品質。 In general, in actual operation, by coiling the hot-rolled steel sheet H by the coiling device 15, it is necessary to control the temperature of the hot-rolled steel sheet H to a predetermined target temperature (temperature suitable for coiling) to maintain the hot-rolled steel sheet H. Quality.

因此,亦可另對上述目標比率設定步驟及冷卻控制步驟追加依時間序列而測定冷卻區間(即冷卻裝置14)之下游側之熱軋鋼板H之溫度之溫度測定步驟、基於前述溫度之測定結果而算出溫度之時間序列平均值之溫度平均值算出步驟、調整冷卻區間內之熱軋鋼板H之上面冷卻除熱量與下面冷卻除熱量之合計值以使前述溫度之時間序列平均值與預定之目標溫度一致之冷卻除熱量調整步驟。 Therefore, a temperature measurement step of measuring the temperature of the hot-rolled steel sheet H on the downstream side of the cooling section (that is, the cooling device 14) in accordance with the time series may be added to the target ratio setting step and the cooling control step, and the measurement result based on the temperature may be added. And calculating a temperature average value of the time series average value of the temperature, adjusting the total value of the cooling heat removal amount of the hot-rolled steel sheet H in the cooling zone and the cooling and heat removal amount below to make the time-series average value of the aforementioned temperature and the predetermined target A cooling-free heat removal step with consistent temperature.

為實現該等新增製程,可使用圖13所示般配置於冷卻裝 置14與盤捲裝置15之間之用於測定熱軋鋼板H之溫度之溫度計40。 In order to implement these new processes, it can be configured in the cooling device as shown in FIG. A thermometer 40 for measuring the temperature of the hot rolled steel sheet H between the coil 14 and the coiling device 15 is placed.

溫度測定步驟中,將對自冷卻裝置14輸送至盤捲裝置15之熱軋鋼板H,藉溫度計40依一定之時間間隔(抽樣間隔)進行設定於熱軋鋼板H之輥軋方向上之位置之溫度測定,並取得溫度測定結果之時間序列資料。另,溫度計40之溫度之測定領域包含熱軋鋼板H之寬度方向之全域。又,若對各溫度測定結果之抽樣時間乘以熱軋鋼板H之送板速度(輸送速度),則可算出已取得各溫度測定結果之熱軋鋼板H之輥軋方向上之位置。即,若將已抽樣各溫度測定結果之時間乘以送板速度,則可使溫度測定結果之時間序列資料與輥軋方向之位置對應。 In the temperature measuring step, the hot-rolled steel sheet H that has been transported from the cooling device 14 to the coiling device 15 is set at a position in the rolling direction of the hot-rolled steel sheet H by a thermometer 40 at a predetermined time interval (sampling interval). The temperature is measured and the time series data of the temperature measurement results are obtained. Further, the measurement range of the temperature of the thermometer 40 includes the entire width direction of the hot-rolled steel sheet H. Further, when the sampling time of each temperature measurement result is multiplied by the sheet feeding speed (conveying speed) of the hot-rolled steel sheet H, the position in the rolling direction of the hot-rolled steel sheet H in which the respective temperature measurement results are obtained can be calculated. That is, when the time of sampling the temperature measurement results is multiplied by the sheet feeding speed, the time series data of the temperature measurement result can be made to correspond to the position of the rolling direction.

溫度平均值算出步驟中,則使用上述之溫度測定結果之時間序列資料而算出溫度測定結果之時間序列平均值。具體而言,每當獲致一定個數之溫度測定結果,可算出該等一定個數量之溫度測定結果之平均值。其次,冷卻除熱量調整步驟中,則調整冷卻區間內之熱軋鋼板H之上面冷卻除熱量與下面冷卻除熱量之合計值,以使算出如上之溫度測定結果之時間序列平均值與預定之目標溫度一致。 In the temperature average calculation step, the time-series average of the temperature measurement results is calculated using the time series data of the temperature measurement results described above. Specifically, the average value of the constant number of temperature measurement results can be calculated each time a certain number of temperature measurement results are obtained. Next, in the cooling and heat removal step, the total value of the cooling heat removal amount of the hot-rolled steel sheet H in the cooling zone and the cooling and heat removal amount below is adjusted to calculate the time series average value of the temperature measurement result as described above and the predetermined target. The temperature is the same.

在此,必須達成使冷卻區間內之熱軋鋼板H之上下導熱係數比率X與目標比率Xt一致之控制目標,同時調整上面冷卻除熱量與下面冷卻除熱量之合計值。 Here, it is necessary to achieve a control target in which the thermal conductivity ratio X above the hot-rolled steel sheet H in the cooling zone is equal to the target ratio Xt, and the total value of the upper cooling heat removal amount and the lower cooling heat removal amount is adjusted.

具體而言,調整上面冷卻除熱量與下面冷卻除熱量之合計值時,亦可基於設定成可對諸如採用以三塚方程式等為 代表之實驗理論式而預先求出之理論值修正與實際之操作實績間之誤差之學習值,而進行冷卻裝置14所連接之冷卻集管之開閉控制。或,亦可基於實際藉溫度計40而測得之溫度,就上述冷卻集管之開閉進行回饋控制或前饋控制。 Specifically, when adjusting the total value of the above cooling heat removal amount and the following cooling heat removal amount, the setting may be based on, for example, adopting the three-dimensional equation. The learning value of the error between the theoretical value correction and the actual operational performance obtained in advance by the experimental theoretical expression is performed, and the cooling header opening and closing control connected to the cooling device 14 is performed. Alternatively, feedback control or feedforward control may be performed on the opening and closing of the cooling header based on the temperature actually measured by the thermometer 40.

其次,使用自上述之溫度計40與如圖13所示而配置於冷卻裝置14與盤捲裝置15間之用於測定熱軋鋼板H之波形之形狀計41取得之資料說明習知之ROT之冷卻控制。 Next, the cooling control of the conventional ROT will be described using the data obtained from the above-described thermometer 40 and the shape meter 41 for measuring the waveform of the hot-rolled steel sheet H disposed between the cooling device 14 and the coiling device 15 as shown in FIG. .

另,形狀計41係用於測定與設定在熱軋鋼板H上之溫度計40相同之測定位置(以下亦將該測定位置稱為定點)之形狀者。此之所謂形狀係就定點測定時所觀察之熱軋鋼板H之高度方向之變動量使用熱軋鋼板H之送板方向之移動量,而藉波之間距量之高度或變動成分之線積分求出之傾斜度。且,同時亦將求出每單位時間之變動量即變動速度。進而,形狀之測定領域與溫度之測定領域同樣包含熱軋鋼板H之寬度方向之全域。與溫度測定結果相同,若對已抽樣各測定結果(傾斜度、變動速度等)之時間乘以送板速度,則可使各測定結果之時間序列資料與輥軋方向之位置對應。 Further, the shape meter 41 is for measuring the shape of the measurement position (hereinafter also referred to as a fixed point) of the thermometer 40 set on the hot-rolled steel sheet H. In this case, the amount of change in the height direction of the hot-rolled steel sheet H observed at the time of the fixed-point measurement is the amount of movement of the hot-rolled steel sheet H in the sheet-feeding direction, and the line of the distance between the waves or the variation component is obtained. The slope is out. At the same time, the amount of change per unit time, that is, the rate of change, will also be obtained. Further, the field of measurement of the shape and the field of measurement of temperature include the entire width direction of the hot-rolled steel sheet H. Similarly to the temperature measurement result, when the time of each sampled measurement result (inclination, fluctuation speed, etc.) is multiplied by the plate feeding speed, the time series data of each measurement result can be made to correspond to the position of the rolling direction.

圖5係顯示通常之操作時之代表性之帶鋼之ROT內冷卻之熱軋鋼板H之溫度變動與傾斜度之關係者。圖5中之熱軋鋼板H之上下導熱係數比率X為1.2:1,上側冷卻能力高於下側冷卻能力。圖5之上側圖表顯示對應與鋼捲先端之距離或定點經過時間之溫度變動,圖5之下側圖表顯示對應與鋼捲先端之距離或定點經過時間之傾斜度。 Fig. 5 is a graph showing the relationship between the temperature fluctuation and the inclination of the hot-rolled steel sheet H cooled in the ROT of a representative steel strip in the usual operation. The thermal conductivity ratio X of the hot-rolled steel sheet H in Fig. 5 is 1.2:1, and the upper side cooling capacity is higher than the lower side cooling capacity. The upper side graph of Fig. 5 shows the temperature change corresponding to the distance from the tip end of the coil or the elapsed time of the fixed point. The lower graph of Fig. 5 shows the inclination corresponding to the distance from the tip end of the coil or the elapsed time of the fixed point.

圖5之領域A係圖13所示之帶鋼先端部咬入盤捲器之前 之領域(因無張力而形狀不佳之領域)。圖5之領域B係帶鋼先端部咬入盤捲器後之領域(因單位張力之影響而使波形平緩改變之領域)。發生於上述熱軋鋼板H之形狀並不平緩之領域A內之較大之溫度變動(即溫度標準偏差Y)則被期待可獲改善。 Field A of Figure 5 is before the strip end of the strip shown in Figure 13 is bitten into the coiler. The field (the area that is not well shaped due to no tension). The field B in Fig. 5 is the field after the tip end of the strip bites into the coiler (the area in which the waveform is gently changed due to the influence of the unit tension). A large temperature variation (i.e., temperature standard deviation Y) occurring in the field A in which the shape of the hot-rolled steel sheet H described above is not gentle is expected to be improved.

因此,本案發明人等人即以抑制ROT之溫度標準偏差Y之增大為目標而致力進行實驗,結果則發現如下。 Therefore, the inventors of the present invention made an experiment aiming at suppressing an increase in the temperature standard deviation Y of the ROT, and as a result, found the following.

圖6與圖5相同,係顯示通常之操作時之代表性之帶鋼之ROT內冷卻之同一形狀傾斜度所對應之溫度變動成分者。上述溫度變動成分係指自實際之鋼板溫度減去溫度之時間序列平均(以下亦稱為「平均溫度」)後之殘差。舉例言之,平均溫度亦可以熱軋鋼板H之波形1周期以上之範圍作為平均。 Fig. 6 is the same as Fig. 5 and shows the temperature fluctuation component corresponding to the inclination of the same shape in the ROT of the representative steel strip in the normal operation. The temperature fluctuation component refers to a residual after subtracting the time series average of the temperature (hereinafter also referred to as "average temperature") from the actual steel sheet temperature. For example, the average temperature may be an average of a range of one cycle or more of the waveform of the hot-rolled steel sheet H.

另,平均溫度原則上係周期單位下之範圍之平均。且,1周期範圍之平均溫度與2周期以上之範圍之平均溫度並無甚大差異,則已藉操作資料而確認。 In addition, the average temperature is in principle the average of the range under the periodic unit. Moreover, the average temperature in the range of one cycle is not significantly different from the average temperature in the range of two cycles or more, and it has been confirmed by the operation data.

因此,可至少算出波形1周期之範圍之平均溫度。熱軋鋼板H之波形之範圍之上限雖無特別之限制,但宜設定為5周期,以獲致精度充分之平均溫度。又,所平均之範圍即便並非周期單位之範圍,若在2~5周期之範圍內,則可獲致可容許之平均溫度。 Therefore, at least the average temperature of the range of one cycle of the waveform can be calculated. The upper limit of the range of the waveform of the hot-rolled steel sheet H is not particularly limited, but it is preferably set to 5 cycles to obtain an average temperature with sufficient accuracy. Further, even if the average range is not in the range of the period unit, if it is within the range of 2 to 5 cycles, an allowable average temperature can be obtained.

在此,若以熱軋鋼板H之垂直方向(與熱軋鋼板H之上下面垂直之方向)之上方為正值,則已定點測得之變動速度為正值之領域中,熱軋鋼板H之溫度(已定點測得之溫 度)相對於熱軋鋼板H之波形1周期以上之範圍之平均溫度而較低時,將上面冷卻除熱量減少之方向及下面冷卻除熱量增加之方向之至少一方決定為控制方向,並在熱軋鋼板H之溫度相對於上述之平均溫度而較高時,將上面冷卻除熱量增加之方向及下面冷卻除熱量減少之方向之至少一方決定為控制方向。 Here, in the field where the vertical direction of the hot-rolled steel sheet H (the direction perpendicular to the upper and lower sides of the hot-rolled steel sheet H) is a positive value, the hot-rolled steel sheet H is in the field where the fluctuation speed measured at the fixed point is a positive value. Temperature (temperature measured at a fixed point) When the temperature is lower than the average temperature of the range of one cycle or more of the waveform of the hot-rolled steel sheet H, at least one of the direction in which the cooling and heat removal is reduced and the direction in which the cooling and heat removal are increased is determined as the control direction, and is in the heat. When the temperature of the rolled steel sheet H is higher than the average temperature described above, at least one of the direction in which the above-described cooling and heat removal increases and the direction in which the cooling and heat removal decreases are determined as the control direction.

又,已定點測得之變動速度為負值之領域中,熱軋鋼板H之溫度相對於上述之平均溫度而較低時,則將上面冷卻除熱量增加之方向及下面冷卻除熱量減少之方向之至少一方決定為控制方向,並在熱軋鋼板H之溫度相對於上述之平均溫度而較高時,將上面冷卻除熱量減少之方向之及下面冷卻除熱量增加之方向之至少一方決定為控制方向。 Further, in the field where the fluctuation speed measured at the fixed point is a negative value, when the temperature of the hot-rolled steel sheet H is lower than the average temperature described above, the direction in which the above-described cooling and heat removal increases and the direction in which the cooling and heat removal are reduced are reduced. At least one of them is determined as the control direction, and when the temperature of the hot-rolled steel sheet H is higher than the average temperature described above, at least one of the direction in which the cooling and heat removal is reduced and the direction in which the cooling and heat removal is increased is determined as the control. direction.

其次,基於決定如上之控制方向,而調整冷卻區間內之熱軋鋼板H之上面冷卻除熱量及下面冷卻除熱量之至少一方,則將如圖7所示,可知與圖6相較,可減少熱軋鋼板H之形狀並不平緩之領域A中發生之溫度變動。 Next, based on the control direction as described above, at least one of the upper surface cooling heat removal amount and the lower surface cooling heat removal amount of the hot-rolled steel sheet H in the cooling section is adjusted, as shown in Fig. 7, it can be seen that it can be reduced as compared with Fig. 6. The shape of the hot-rolled steel sheet H is not gentle in the temperature fluctuation occurring in the field A.

進行與上述相反之操作之情形則揭露如下。已定點測得之變動速度為正值之領域中,熱軋鋼板H之溫度相對於熱軋鋼板H之平均溫度而較低時,則將上面冷卻除熱量增加之方向及下面冷卻除熱量減少之方向之至少一方決定為控制方向,並在熱軋鋼板H之溫度相對於上述之平均溫度而較高時,將上面冷卻除熱量減少之方向及下面冷卻除熱量增加之方向之至少一方決定為控制方向。 The case where the operation opposite to the above is performed is disclosed as follows. In the field where the fluctuating speed measured at a fixed point is positive, when the temperature of the hot-rolled steel sheet H is lower than the average temperature of the hot-rolled steel sheet H, the direction of the upper cooling and the removal of heat and the cooling and heat removal are reduced. At least one of the directions is determined as the control direction, and when the temperature of the hot-rolled steel sheet H is higher than the average temperature, at least one of the direction in which the cooling and heat removal is reduced and the direction in which the cooling and heat removal are increased is determined as the control. direction.

又,已定點測得之變動速度為負值之領域中,熱軋鋼板 H相對於上述之平均溫度而較低時,則將上面冷卻除熱量減少之方向及下面冷卻除熱量增加之方向之至少一方決定為控制方向,並在熱軋鋼板H之溫度相對於上述之平均溫度而較高時,將上面冷卻除熱量增加之方向及下面冷卻除熱量減少之方向之至少一方決定為控制方向。 Moreover, in the field where the rate of change measured at a fixed point is negative, the hot rolled steel sheet When H is lower than the average temperature described above, at least one of the direction in which the above-described cooling and heat removal is reduced and the direction in which the cooling and heat removal is increased is determined as the control direction, and the temperature of the hot-rolled steel sheet H is averaged relative to the above. When the temperature is high, at least one of the direction in which the above-described cooling and heat removal is increased and the direction in which the cooling and heat removal are reduced is determined as the control direction.

其次,基於決定如上之控制方向而調整冷卻區間內之熱軋鋼板H之上面冷卻除熱量及下面冷卻除熱量之至少一方,則如圖8所示,可知與圖6相較,將擴大熱軋鋼板H之形狀並不平緩之領域A中發生之溫度變動。另,此所說明之例亦非可改變冷卻停止溫度之前提。 Next, by adjusting at least one of the upper surface cooling heat removal amount and the lower surface cooling heat removal amount of the hot-rolled steel sheet H in the cooling section based on the above-described control direction, as shown in FIG. 8, it is understood that the hot rolling is expanded as compared with FIG. The shape of the steel sheet H is not gentle in the temperature fluctuation occurring in the field A. In addition, the examples described herein may not be changed before the cooling stop temperature can be changed.

利用上述關係,則可確定為減少溫度變動即溫度標準偏差Y,可調整冷卻裝置14之上側冷卻裝置14a與下側冷卻裝置14b之任一方之冷卻能力。另,表2係上述關係之匯整表格。 According to the above relationship, it is possible to determine the cooling capacity of the upper side cooling device 14a and the lower side cooling device 14b of the cooling device 14 by reducing the temperature variation, that is, the temperature standard deviation Y. In addition, Table 2 is a summary table of the above relationship.

如上所述,亦可對上述目標比率設定步驟及冷卻控制步驟另行追加依時間序列測定冷卻區間之下游側之熱軋鋼板H之溫度(定點上之溫度)之溫度測定步驟、依時間序列測定與熱軋鋼板H之溫度測定部位同一部位(定點)上之熱軋鋼板H之垂直方向之變動速度之變動速度測定步驟、基於溫度測定結果及變動速度測定結果而決定上面冷卻除熱 量及下面冷卻除熱量之控制方向之控制方向決定步驟、基於已決定之控制方向而調整冷卻區間內之熱軋鋼板H之上面冷卻除熱量及下面冷卻除熱量之至少一方之冷卻除熱量調整步驟。 As described above, the target ratio setting step and the cooling control step may be separately added to the temperature measurement step of measuring the temperature (temperature at the fixed point) of the hot-rolled steel sheet H on the downstream side of the cooling section in time series, and measuring by time series and The measurement procedure of the fluctuation speed of the fluctuation speed of the hot-rolled steel sheet H in the same portion (fixed point) of the hot-rolled steel sheet H at the same portion (fixed point) is determined based on the temperature measurement result and the fluctuation speed measurement result. The control direction determining step of the amount and the control direction of the cooling and heat removal, and the cooling and heat removing step of adjusting at least one of the upper cooling heat removal amount and the lower cooling heat removal amount of the hot rolled steel sheet H in the cooling section based on the determined control direction .

在此,控制方向決定步驟中,一如上述,於熱軋鋼板H之定點上之變動速度為正值之領域中,熱軋鋼板H之定點上之溫度相對於熱軋鋼板H之定點上之平均溫度而較低時,將上面冷卻除熱量減少之方向及下面冷卻除熱量增加之方向之至少一方決定為控制方向,並在熱軋鋼板H之溫度相對於上述之平均溫度而較高時,將上面冷卻除熱量增加之方向及下面冷卻除熱量減少之方向之至少一方決定為控制方向。 Here, in the control direction determining step, as in the above, in the field where the fluctuation speed of the hot-rolled steel sheet H is positive, the temperature at the fixed point of the hot-rolled steel sheet H is fixed with respect to the fixed point of the hot-rolled steel sheet H. When the average temperature is low, at least one of the direction in which the cooling and heat removal is reduced and the direction in which the cooling and heat removal are increased is determined as the control direction, and when the temperature of the hot-rolled steel sheet H is higher than the average temperature described above, At least one of the direction in which the above-described cooling and heat removal is increased and the direction in which the cooling and heat removal are reduced is determined as the control direction.

又,上述控制方向決定步驟中,於上述變動速度為負值之領域中,熱軋鋼板H之溫度相對於上述之平均溫度而較低時,則將上面冷卻除熱量增加之方向及下面冷卻除熱量減少之方向之至少一方決定為控制方向,並在熱軋鋼板H之溫度相對於上述之平均溫度而較高時,將上面冷卻除熱量減少之方向及下面冷卻除熱量增加之方向之至少一方決定為控制方向。 Further, in the control direction determining step, in the field where the fluctuation speed is a negative value, when the temperature of the hot-rolled steel sheet H is lower than the average temperature, the direction of the upper cooling and heat removal is lowered and the lower surface is cooled. At least one of the directions in which the heat is reduced is determined as the control direction, and when the temperature of the hot-rolled steel sheet H is higher than the average temperature, at least one of the direction of cooling and heat removal and the direction of cooling and heat removal are increased. Decided to control the direction.

另,上述冷卻方法亦須達成使冷卻區間內之熱軋鋼板H之上下導熱係數比率X與目標比率Xt一致之控制目標,同時調整上面冷卻除熱量與下面冷卻除熱量。 Further, the above cooling method is also required to achieve a control target in which the thermal conductivity ratio X above the hot-rolled steel sheet H in the cooling section is made to coincide with the target ratio Xt, and the above-described cooling and heat removal and the cooling and heat removal are adjusted.

另,調整上側冷卻裝置14a之冷卻能力與下側冷卻裝置14b之冷卻能力時,舉例言之,亦可分別就上側冷卻裝置14a之冷卻口31所連接之冷卻集管與下側冷卻裝置14b 之冷卻口31所連接之冷卻集管進行開閉控制。或,亦可控制上側冷卻裝置14a與下側冷卻裝置14b之各冷卻集管之冷卻能力。即,亦可調整自各冷卻口31噴射之冷卻水之水量密度、壓力、水溫之至少一項。 Further, when the cooling capacity of the upper side cooling device 14a and the cooling capacity of the lower side cooling device 14b are adjusted, for example, the cooling header and the lower side cooling device 14b connected to the cooling port 31 of the upper side cooling device 14a, respectively. The cooling header connected to the cooling port 31 is opened and closed. Alternatively, the cooling capacity of each of the cooling headers of the upper side cooling device 14a and the lower side cooling device 14b may be controlled. That is, at least one of the water amount density, the pressure, and the water temperature of the cooling water sprayed from each of the cooling ports 31 may be adjusted.

又,亦可疏減上側冷卻裝置14a與下側冷卻裝置14b之冷卻集管(冷卻口31)而調整自上側冷卻裝置14a與下側冷卻裝置14b噴射之冷卻水之流量及壓力。舉例言之,疏減冷卻集管前之上側冷卻裝置14a之冷卻能力高於下側冷卻裝置14b之冷卻能力時,宜疏減構成上側冷卻裝置14a之冷卻集管。 Further, the cooling headers (cooling ports 31) of the upper cooling device 14a and the lower cooling device 14b can be reduced to adjust the flow rate and pressure of the cooling water sprayed from the upper cooling device 14a and the lower cooling device 14b. For example, when the cooling capacity of the upper side cooling device 14a before the cooling header is reduced is higher than the cooling capacity of the lower side cooling device 14b, the cooling header constituting the upper side cooling device 14a should be reduced.

藉業經上述調整之冷卻能力而自上側冷卻裝置14a朝熱軋鋼板H上面噴射冷卻水,並自下側冷卻裝置14b朝熱軋鋼板H下面噴射冷卻水,即可均一地冷卻熱軋鋼板H。 By the cooling capacity of the above-described adjustment, the cooling water is sprayed from the upper cooling device 14a onto the hot-rolled steel sheet H, and the cooling water is sprayed from the lower cooling device 14b toward the lower surface of the hot-rolled steel sheet H, whereby the hot-rolled steel sheet H can be uniformly cooled.

以上之實施形態中,已說明使熱軋鋼板H之送板速度固定為600m/min而求出圖3所示之相關資料之情形。進而,細節雖留待後述,但本案發明人等人致力檢討之結果,已知若將送板速度設在550m/min以上,即可使熱軋鋼板H之冷卻更為均一。 In the above embodiment, the case where the sheet feeding speed of the hot-rolled steel sheet H is fixed to 600 m/min and the relevant data shown in Fig. 3 is obtained has been described. Further, although the details are to be described later, the inventors of the present invention have made efforts to review the results. It is known that the cooling of the hot-rolled steel sheet H can be more uniform if the sheet feeding speed is set to 550 m/min or more.

已知若將熱軋鋼板H之送板速度設在550m/min以上,則即便朝熱軋鋼板H噴射冷卻水,亦可明顯減少熱軋鋼板H上之積水之影響。因此,亦可避免積水所致熱軋鋼板H之冷卻不均。 It is known that when the sheet feeding speed of the hot-rolled steel sheet H is set to 550 m/min or more, even if the cooling water is sprayed toward the hot-rolled steel sheet H, the influence of the water accumulated on the hot-rolled steel sheet H can be remarkably reduced. Therefore, it is also possible to avoid uneven cooling of the hot-rolled steel sheet H due to water accumulation.

以上之實施形態中,冷卻裝置14所進行熱軋鋼板H之冷卻宜在精軋機出側溫度至上述熱軋鋼板H之溫度為600℃之範圍內進行。熱軋鋼板H之溫度為600℃以上之溫度 領域乃所謂膜態沸騰領域。即,此時,可避開所謂變態沸騰領域而在膜態沸騰領域中進行熱軋鋼板H之水冷。變態沸騰領域中,朝熱軋鋼板H之表面噴射冷卻水後,上述熱軋鋼板H表面上將併存為蒸氣膜所覆蓋之部分及冷卻水直接對熱軋鋼板H噴射之部分。 In the above embodiment, the cooling of the hot-rolled steel sheet H by the cooling device 14 is preferably performed within a range from the temperature at the exit of the finishing mill to the temperature of the hot-rolled steel sheet H of 600 °C. The temperature of hot rolled steel sheet H is 600 ° C or higher The field is the so-called membrane boiling field. That is, at this time, water cooling of the hot-rolled steel sheet H can be performed in the film boiling field in the so-called metamorphic boiling field. In the field of the abnormal boiling, after the cooling water is sprayed onto the surface of the hot-rolled steel sheet H, the surface of the hot-rolled steel sheet H is coexisted as a portion covered with the vapor film and the portion of the cooling water directly sprayed onto the hot-rolled steel sheet H.

因此,無法均一地冷卻熱軋鋼板H。另,膜態沸騰領域中,係在熱軋鋼板H之表面整體為蒸氣膜所覆蓋之狀態下進行熱軋鋼板H之冷卻,故可均一地冷卻熱軋鋼板H。因此,如本實施形態般,在熱軋鋼板H之溫度為600℃以上之範圍內,可更為均一地冷卻熱軋鋼板H。 Therefore, the hot rolled steel sheet H cannot be uniformly cooled. Further, in the field of film boiling, the hot-rolled steel sheet H is cooled in a state where the entire surface of the hot-rolled steel sheet H is covered with a vapor film, so that the hot-rolled steel sheet H can be uniformly cooled. Therefore, as in the present embodiment, the hot-rolled steel sheet H can be more uniformly cooled in a range in which the temperature of the hot-rolled steel sheet H is 600 ° C or more.

以上之實施形態中,在使用圖3所示之相關資料而調整冷卻裝置14之上側冷卻裝置14a之冷卻能力及下側冷卻裝置14b之冷卻能力時,係使熱軋鋼板H之波形之傾斜度與熱軋鋼板H之送板速度固定。然而,舉例言之,該等熱軋鋼板H之傾斜度及送板速度亦可能就各鋼捲而不同。 In the above embodiment, when the cooling capacity of the upper side cooling device 14a of the cooling device 14 and the cooling capacity of the lower side cooling device 14b are adjusted using the related data shown in Fig. 3, the inclination of the waveform of the hot rolled steel sheet H is adjusted. The plate feeding speed with the hot-rolled steel sheet H is fixed. However, by way of example, the inclination of the hot-rolled steel sheets H and the sheet feeding speed may also differ for each steel coil.

依據本案發明人等人之調查,舉例言之,如圖9所示,若熱軋鋼板H之波形之傾斜度增大,則熱軋鋼板H之溫度標準偏差Y亦將增大。即,如圖10所示,隨著上下導熱係數比率X偏離“1”,溫度標準偏差Y將對應傾斜度(傾斜度之感度)而增大。圖10中,即如上述而就各傾斜度藉V字之回歸線顯示上下導熱係數比率X與溫度標準偏差Y之關係。另,圖10中,熱軋鋼板H之送板速度固定為10m/sec(600m/min)。 According to the investigation by the inventors of the present invention, as an example, as shown in Fig. 9, when the inclination of the waveform of the hot-rolled steel sheet H is increased, the temperature standard deviation Y of the hot-rolled steel sheet H is also increased. That is, as shown in FIG. 10, as the upper and lower thermal conductivity ratio X deviates from "1", the temperature standard deviation Y increases in accordance with the inclination (sensitivity of the inclination). In Fig. 10, as described above, the relationship between the upper and lower thermal conductivity ratios X and the temperature standard deviation Y is shown by the regression line of each of the inclinations by the V-shape. Further, in Fig. 10, the sheet feeding speed of the hot-rolled steel sheet H is fixed at 10 m/sec (600 m/min).

又,舉例言之,如圖11所示,一旦熱軋鋼板H之 送板速度為高速,則熱軋鋼板H之溫度標準偏差Y將增大。即,如圖12所示,隨著上下導熱係數比率X偏離“1”,溫度標準偏差Y將對應送板速度(送板速度之感度)而增大。圖12中,一如上述,已就各送板速度藉V字之回歸線顯示上下導熱係數比率X與溫度標準偏差Y之關係。另,圖12中,熱軋鋼板H之波形之傾斜度固定為2%。 Also, by way of example, as shown in FIG. 11, once the hot rolled steel sheet H is When the feed speed is high, the temperature standard deviation Y of the hot-rolled steel sheet H will increase. That is, as shown in FIG. 12, as the upper and lower thermal conductivity ratio X deviates from "1", the temperature standard deviation Y increases in accordance with the plate feeding speed (sensitivity of the plate feeding speed). In Fig. 12, as described above, the relationship between the upper and lower thermal conductivity ratio X and the temperature standard deviation Y has been shown by the regression line of the V word for each of the sheet feeding speeds. Further, in Fig. 12, the inclination of the waveform of the hot-rolled steel sheet H was fixed at 2%.

如上所述,熱軋鋼板H之傾斜度及送板速度並非固定時,可定性評價溫度標準偏差Y對應上下導熱係數比率X之改變,但無法正確地定量評價之。 As described above, when the inclination of the hot-rolled steel sheet H and the sheet feeding speed are not fixed, the temperature standard deviation Y can be qualitatively evaluated corresponding to the change in the upper and lower thermal conductivity ratios X, but it cannot be accurately quantitatively evaluated.

因此,將預先使熱軋鋼板H之上下導熱係數比率X固定,並諸如圖9所示,使傾斜度階段性地自3%變更至0%,而預先求出顯示各傾斜度與熱軋鋼板H之冷卻後之溫度標準偏差Y之相關關係之表格資料。其次,藉內插函數而將對應實際之熱軋鋼板H之傾斜度z%之溫度標準偏差Y修正成對應預定之傾斜度之溫度標準偏差Y’。具體而言,設定預定之傾斜度為2%作為修正條件時,則基於傾斜度z%時之溫度標準偏差Yz並藉以下式(1)算出溫度標準偏差Yz’。或,舉例言之,亦可藉最小平方法等算出圖9之傾斜度之斜率α,再使用該斜率α而算出溫度標準偏差Yz’。 Therefore, the thermal conductivity ratio X of the upper and lower portions of the hot-rolled steel sheet H is fixed in advance, and as shown in FIG. 9, the inclination is changed stepwise from 3% to 0%, and the respective inclinations and the hot-rolled steel sheets are obtained in advance. Table data on the correlation between the temperature standard deviation Y after cooling and H. Next, the temperature standard deviation Y corresponding to the inclination z% of the actual hot-rolled steel sheet H is corrected by the interpolation function to the temperature standard deviation Y' corresponding to the predetermined inclination. Specifically, when the predetermined inclination is set to 2% as the correction condition, the temperature standard deviation Yz' is calculated by the following formula (1) based on the temperature standard deviation Yz at the inclination z%. Alternatively, for example, the slope α of the inclination of Fig. 9 may be calculated by the least square method or the like, and the temperature standard deviation Yz' may be calculated using the slope α.

Yz’=Yz×2/z....(1) Yz’=Yz×2/z. . . . (1)

又,亦可藉圖10所示之V字曲線之迴歸公式將傾斜度修正成預定之傾斜度,並自上述迴歸公式導出溫度標準偏差Y。另,表3則顯示如圖10所示般使上下導熱係數比率X相對於圖9中之傾斜度而變動後之熱軋鋼板H之溫度標 準偏差Y、自熱軋鋼板H之各溫度標準偏差Y減去最小值Ymin(傾斜度為1%時,Ymin=1.2℃,傾斜度為2%時,Ymin=2.3℃,傾斜度為3%時,Ymin=3.5℃)後之值(與最小值之標準偏差之差分)及各溫度標準偏差Y之評價。 Moreover, the inclination can be corrected to a predetermined inclination by the regression formula of the V-shaped curve shown in FIG. 10, and the temperature standard deviation Y can be derived from the above regression formula. In addition, Table 3 shows the temperature scale of the hot-rolled steel sheet H after the upper and lower thermal conductivity ratio X is changed with respect to the inclination in FIG. 9 as shown in FIG. Quasi-deviation Y, the standard deviation Y of each temperature from the hot-rolled steel sheet H minus the minimum value Ymin (Ymin=1.2°C when the inclination is 1%, Ymin=2.3°C when the inclination is 2%, and the inclination is 3% The value after Ymin = 3.5 ° C) (the difference between the standard deviation from the minimum value) and the evaluation of the temperature standard deviation Y.

上述表3之上下導熱係數比率X之顯示與評價之基準與表1之評價相同故省略其說明。使用上述圖10或表3,即可導出對應傾斜度之熱軋鋼板H之溫度標準偏差Y。其次,舉例言之,將傾斜度修正為2%時,表3之評價則為“B”,即,可將與熱軋鋼板H之最小值之標準偏差之差分為10℃以內之上下導熱係數比率X設為1.1。 The display and evaluation criteria of the upper and lower thermal conductivity ratios X in the above Table 3 are the same as those in Table 1, and the description thereof will be omitted. Using the above FIG. 10 or Table 3, the temperature standard deviation Y of the hot-rolled steel sheet H corresponding to the inclination can be derived. Secondly, for example, when the inclination is corrected to 2%, the evaluation of Table 3 is "B", that is, the difference from the standard deviation of the minimum value of the hot-rolled steel sheet H can be 10 ° C or less. The ratio X is set to 1.1.

同樣地,諸如圖11所示,可使送板速度階段性地自5m/sec(300m/min)變更為20m/sec(1200m/min),而預先求出顯示各送板速度與熱軋鋼板H之冷卻後之溫度標準偏差Y之相關關係之表格資料。其次,藉內插函數將對應實際之熱軋鋼板H之送板速度v(m/sec)之溫度標準偏差Y修正成對應預定之送板速度之溫度標準偏差Y’。具體而言,將預定之送板速度設為10(m/sec)作為修正條件時,係基於送板速度v(m/sec)時之溫度標準偏差Yv並藉以下之式(2)而算出溫度標準偏差Yv’。或,舉例言之,亦可藉最小平方法等算出圖11之送板速度之斜率α,並使用該斜率α而算出溫度標準偏差Yv’。 Similarly, as shown in FIG. 11, the sheet feeding speed can be changed from 5 m/sec (300 m/min) to 20 m/sec (1200 m/min) in stages, and the respective sheet feeding speeds and hot-rolled steel sheets can be obtained in advance. Table data on the correlation between the temperature standard deviation Y after cooling and H. Next, the temperature standard deviation Y corresponding to the actual sheet feeding speed v (m/sec) of the actual hot-rolled steel sheet H is corrected by the interpolation function to the temperature standard deviation Y' corresponding to the predetermined sheet feeding speed. Specifically, when the predetermined sheet feeding speed is set to 10 (m/sec) as the correction condition, the temperature standard deviation Yv at the sheet feeding speed v (m/sec) is calculated by the following formula (2). Temperature standard deviation Yv'. Alternatively, for example, the slope α of the sheet feeding speed of Fig. 11 may be calculated by the least square method or the like, and the temperature standard deviation Yv' may be calculated using the slope α.

Yz’=Yv×10/v....(2) Yz’=Yv×10/v. . . . (2)

又,亦可藉圖12所示之V字曲線之迴歸公式將送板速度修正成預定之送板速度,並自上述迴歸公式導出溫度標準偏差Y。另,表4則顯示如圖12所示般使上下導熱係數比率X相對於圖11中之送板速度而變動後之熱軋鋼板H之溫度標準偏差Y、自各溫度標準偏差Y減去最小值Ymin(送板速度為5m/s時,Ymin=1.2℃,送板速度為10m/s時,Ymin=2.3℃,送板速度為15m/s時,Ymin=3.5℃,送板速度為20m/s時,Ymin=4.6℃)後之值(與最小值之標準偏差之差分)及各溫度標準偏差Y之評價。 Moreover, the plate feed speed can be corrected to a predetermined plate feed speed by the regression formula of the V-shaped curve shown in FIG. 12, and the temperature standard deviation Y can be derived from the above regression formula. Further, in Table 4, the temperature standard deviation Y of the hot-rolled steel sheet H after the upper and lower thermal conductivity ratio X is changed with respect to the sheet feeding speed in Fig. 11 is shown as shown in Fig. 12, and the minimum value is subtracted from each temperature standard deviation Y. Ymin (Ymin=1.2°C when the plate feeding speed is 5m/s, Ymin=2.3°C when the plate feeding speed is 10m/s, Ymin=3.5°C when the plate feeding speed is 15m/s, and the feeding speed is 20m/ In s, the value after Ymin = 4.6 ° C) (the difference between the standard deviation from the minimum value) and the evaluation of the temperature standard deviation Y.

上述表4之上下導熱係數比率X之顯示與評價之基準與表1之評價相同故省略其說明。使用上述圖12或表4,即可導出對應送板速度之熱軋鋼板H之溫度標準偏差Y。其次, 舉例言之,將送板速度修正為10m/sec時,表4之評價則為“B”,即,可將與熱軋鋼板H之最小值之標準偏差之差分為10℃以內之上下導熱係數比率X設為1.1。 The display and evaluation criteria of the upper and lower thermal conductivity ratios X in the above Table 4 are the same as those in Table 1, and the description thereof will be omitted. Using the above-described Fig. 12 or Table 4, the temperature standard deviation Y of the hot-rolled steel sheet H corresponding to the sheet feeding speed can be derived. Secondly, For example, when the sheet feeding speed is corrected to 10 m/sec, the evaluation of Table 4 is "B", that is, the difference from the standard deviation of the minimum value of the hot-rolled steel sheet H can be 10 ° C or less. The ratio X is set to 1.1.

如上所述,即便熱軋鋼板H之傾斜度及送板速度並非固定,藉修正溫度標準偏差Y亦可正確地定量評價對應上下導熱係數比率之溫度標準偏差Y之變化。 As described above, even if the inclination of the hot-rolled steel sheet H and the sheet feeding speed are not fixed, the change in the temperature standard deviation Y corresponding to the upper and lower thermal conductivity ratios can be accurately quantitatively evaluated by the corrected temperature standard deviation Y.

以上之實施形態中,亦可測定已藉冷卻裝置14而冷卻之熱軋鋼板H之溫度與波形,並基於其測定結果而調整上側冷卻裝置14a之冷卻能力與下側冷卻裝置14b之冷卻能力。即,亦可就該等上側冷卻裝置14a與下側冷卻裝置14b之冷卻能力進行回饋控制。 In the above embodiment, the temperature and waveform of the hot-rolled steel sheet H cooled by the cooling device 14 can be measured, and the cooling capacity of the upper cooling device 14a and the cooling capacity of the lower cooling device 14b can be adjusted based on the measurement results. That is, the feedback control of the cooling capacities of the upper side cooling device 14a and the lower side cooling device 14b can be performed.

此時,則如圖13所示,於冷卻裝置14與盤捲裝置15之間配置有用於測定熱軋鋼板H之溫度之溫度計40,以及用於測定熱軋鋼板H之波形之形狀計41。 At this time, as shown in FIG. 13, between the cooling device 14 and the coiling device 15, a thermometer 40 for measuring the temperature of the hot-rolled steel sheet H and a shape gauge 41 for measuring the waveform of the hot-rolled steel sheet H are disposed.

其次,對送板中之熱軋鋼板H藉溫度計40與形狀計41而分別於同點上進行溫度及形狀之定點測定,並加以測得作為時間序列資料。另,溫度之測定領域包含熱軋鋼板H之寬度方向之全域。且,形狀代表定點測定時所觀察之熱軋鋼板H之高度方向之變動量。進而,形狀之測定領域與溫度之測定領域相同而包含熱軋鋼板H之寬度方向之全域。對其等之抽樣時間乘以送板速度,即可使溫度及變動速度等之測定結果之時間序列資料與輥軋方向之位置對應。 Next, the hot-rolled steel sheet H in the feed plate is subjected to fixed-point measurement of temperature and shape at the same point by the thermometer 40 and the shape meter 41, and is measured as time-series data. Further, the measurement range of the temperature includes the entire width direction of the hot-rolled steel sheet H. Further, the shape represents the amount of change in the height direction of the hot-rolled steel sheet H observed at the time of the fixed point measurement. Further, the measurement range of the shape is the same as the measurement range of the temperature, and includes the entire width direction of the hot-rolled steel sheet H. By multiplying the sampling time by the plate feeding speed, the time series data of the measurement results such as the temperature and the fluctuation speed can be correlated with the position of the rolling direction.

如參照圖5、圖6、圖7及圖8之說明,於熱軋鋼板H之定點上之變動速度為正值之領域中,熱軋鋼板H之定點上之溫度相對於定點上之平均溫度而較低時,減少上側冷卻能力(上面冷卻除熱量)即可減少溫度標準偏差Y。同樣地,增大下側冷卻能力(下面冷卻除熱量),可減少溫度標準偏差Y。利用上述關係,即確定為減少溫度標準偏差Y,可調整冷卻裝置14之上側冷卻裝置14a與下側冷卻裝置14b之任一方之冷卻能力。 As described with reference to FIG. 5, FIG. 6, FIG. 7, and FIG. 8, in the field where the fluctuation speed of the hot-rolled steel sheet H is positive, the temperature at the fixed point of the hot-rolled steel sheet H is relative to the average temperature at the fixed point. At lower times, the upper standard cooling capacity (the above cooling and heat removal) can be reduced to reduce the temperature standard deviation Y. Similarly, by increasing the lower side cooling capacity (cooling heat removal below), the temperature standard deviation Y can be reduced. With the above relationship, that is, it is determined that the temperature standard deviation Y is reduced, the cooling capacity of either the upper side cooling device 14a and the lower side cooling device 14b of the cooling device 14 can be adjusted.

即,若掌握與該等熱軋鋼板H之波形對應之溫度之變動位置,即可明瞭現在已發生之溫度標準偏差Y係因上側冷卻或下側冷卻之何者而發生。因此,可決定用於減小溫度標準偏差Y之上側冷卻能力(上面冷卻除熱量)與下側冷卻能力(下面冷卻除熱量)之增減方向(控制方向),並調整上下導熱係數比率X。 In other words, if the temperature change position corresponding to the waveform of the hot-rolled steel sheet H is grasped, it can be understood that the temperature standard deviation Y that has occurred now occurs due to either the upper side cooling or the lower side cooling. Therefore, it is possible to determine the direction of increase and decrease (control direction) for lowering the cooling capacity (the upper heat removal heat removal) and the lower side cooling capacity (the lower cooling heat removal) of the temperature standard deviation Y, and to adjust the upper and lower thermal conductivity ratio X.

又,可基於溫度標準偏差Y之大小而決定上下導熱係數比率X,以將上述溫度標準偏差Y控制在容許範圍諸如最小值Ymin至最小值Ymin+10℃以內之範圍內。該上下導熱係數比率X之決定方法與參照圖3及圖4而已說明之上述實施形態相同,故省略詳細之說明。另,將上述溫度標準偏差Y控制在最小值Ymin至最小值Ymin+10℃以內之範圍內,即可將降伏應力、拉伸強度等之偏差控制在製造容許範圍內,並均一地冷卻熱軋鋼板H。 Further, the upper and lower thermal conductivity ratios X may be determined based on the magnitude of the temperature standard deviation Y to control the temperature standard deviation Y within a range from the allowable range such as the minimum value Ymin to the minimum value Ymin + 10 °C. The method of determining the upper and lower thermal conductivity ratios X is the same as that of the above-described embodiment described with reference to FIGS. 3 and 4, and thus detailed description thereof will be omitted. In addition, by controlling the temperature standard deviation Y within the range from the minimum value Ymin to the minimum value Ymin + 10 ° C, the deviation of the relief stress, the tensile strength, and the like can be controlled within the manufacturing tolerance range, and the hot rolling is uniformly cooled. Steel plate H.

又,雖產生不小之偏差,但冷卻水量密度比率若相對於可使溫度標準偏差Y為最小值Ymin之冷卻水量密度比率而在±5%以內,則可將溫度標準偏差Y控制在最小值Ymin至最小值Ymin+10℃以內之範圍內。即,使用冷卻水量密度時,宜將冷卻水量密度之上下比率(冷卻水量密度比率)設成相對於可使溫度標準偏差Y為最小值Ymin之冷卻水量密度比率而在5%以內。但,上述容許範圍非必包含上下同水量密度。 Further, although there is no small deviation, if the cooling water amount density ratio is within ±5% with respect to the cooling water amount density ratio which allows the temperature standard deviation Y to be the minimum value Ymin, the temperature standard deviation Y can be controlled to the minimum value. Ymin is within the range of the minimum value Ymin + 10 °C. In other words, when the cooling water amount density is used, it is preferable to set the ratio of the cooling water amount density to the upper (the cooling water amount density ratio) to be within 5% with respect to the cooling water amount density ratio at which the temperature standard deviation Y is the minimum value Ymin. However, the above tolerance range does not necessarily include the same water volume density.

如上所述,可就上側冷卻裝置14a與下側冷卻裝置14b之冷卻能力進行回饋控制而加以調整為適於進行定 性及定量評價之冷卻能力,故可更為提昇其後熱軋鋼板H之冷卻之均一性。 As described above, the feedback control of the cooling capacities of the upper side cooling device 14a and the lower side cooling device 14b can be adjusted to be suitable for setting The cooling capacity of the hot-rolled steel sheet H can be further improved by the cooling capacity of the hot-rolled steel sheet.

以上之實施形態中,如圖14所示,亦可將進行熱軋鋼板H之冷卻之冷卻區間在輥軋方向上分割成複數諸如2個分割冷卻區間Z1、Z2。各分割冷卻區間Z1、Z2則分別設有冷卻裝置14。又,各分割冷卻區間Z1、Z2之邊界即分割冷卻區間Z1、Z2之下游側分別設有溫度計40與形狀計41。另,本實施形態中,雖將冷卻區間分割成2個分割冷卻區間,但分割數不受限於此而可加以任意設定。舉例言之,冷卻區間亦可分割成1個~5個分割冷卻區間。 In the above embodiment, as shown in FIG. 14, the cooling section for cooling the hot-rolled steel sheet H may be divided into a plurality of divided cooling sections Z1 and Z2 in the rolling direction. Each of the divided cooling sections Z1 and Z2 is provided with a cooling device 14, respectively. Further, a thermometer 40 and a shape meter 41 are provided on the downstream sides of the divided cooling sections Z1 and Z2, which are boundaries of the divided cooling sections Z1 and Z2, respectively. Further, in the present embodiment, the cooling section is divided into two divided cooling sections, but the number of divisions is not limited thereto and can be arbitrarily set. For example, the cooling interval can also be divided into 1 to 5 divided cooling intervals.

此時,則藉各溫度計40與各形狀計41而分別測定分割冷卻區間Z1與Z2之下游側之熱軋鋼板H之溫度與波形。其次,基於其等之測定結果而控制各分割冷卻區間Z1、Z2之上側冷卻裝置14a及下側冷卻裝置14b之冷卻能力。此時,將控制冷卻能力以將熱軋鋼板H之溫度標準偏差Y控制在容許範圍諸如上述之最小值Ymin至最小值Ymin+10℃以內之範圍內。如此,即可調整各分割冷卻區間Z1、Z2之熱軋鋼板H之上面冷卻除熱量及下面冷卻除熱量之至少一方。 At this time, the temperature and waveform of the hot-rolled steel sheet H on the downstream side of the divided cooling sections Z1 and Z2 are measured by the thermometers 40 and the respective shape gauges 41, respectively. Next, the cooling ability of the upper side cooling device 14a and the lower side cooling device 14b of each divided cooling zone Z1, Z2 is controlled based on the measurement result of these. At this time, the cooling ability is controlled to control the temperature standard deviation Y of the hot-rolled steel sheet H within a range of the allowable range such as the minimum value Ymin to the minimum value Ymin + 10 ° C described above. In this way, at least one of the upper surface of the hot-rolled steel sheet H of each of the divided cooling sections Z1 and Z2, and the heat of cooling and the heat of the lower side can be adjusted.

舉例言之,於分割冷卻區間Z1中,可基於其下游側之溫度計40與形狀計41之測定結果,而就上側冷卻裝置14a與下側冷卻裝置14b之冷卻能力進行回饋控制,並調整上面冷卻除熱量及下面冷卻除熱量之至少一方。 For example, in the divided cooling zone Z1, based on the measurement results of the thermometer 40 and the shape meter 41 on the downstream side thereof, feedback control can be performed on the cooling capacities of the upper side cooling device 14a and the lower side cooling device 14b, and the above cooling can be adjusted. At least one of heat removal and heat removal below.

又,於分割冷卻區間Z2中,亦可基於其下游側之溫度計40與形狀計41之測定結果,而就上側冷卻裝置14a與下側 冷卻裝置14b之冷卻能力進行前饋控制或回饋控制。任一情形下均可於分割冷卻區間Z2中調整上面冷卻除熱量及下面冷卻除熱量之至少一方。 Further, in the divided cooling zone Z2, the upper side cooling device 14a and the lower side may be based on the measurement results of the thermometer 40 and the shape meter 41 on the downstream side. The cooling capacity of the cooling device 14b is subjected to feedforward control or feedback control. In either case, at least one of the upper cooling heat removal and the lower cooling heat removal may be adjusted in the divided cooling zone Z2.

另,基於溫度計40與形狀計41之測定結果而控制上側冷卻裝置14a與下側冷卻裝置14b之冷卻能力之方法與參照圖5~圖8而已說明之上述實施形態相同,故省略詳細之說明。 The method of controlling the cooling ability of the upper side cooling device 14a and the lower side cooling device 14b based on the measurement results of the thermometer 40 and the shape meter 41 is the same as that of the above-described embodiment described with reference to FIGS. 5 to 8, and therefore detailed description thereof will be omitted.

此時,係於各分割冷卻區間Z1、Z2個別中調整熱軋鋼板H之上面冷卻除熱量及下面冷卻除熱量之至少一方,故可進行更嚴密之控制。因此,可更為均一地冷卻熱軋鋼板H。 At this time, at least one of the cooling heat removal and the lower cooling and heat removal of the hot-rolled steel sheet H are adjusted in each of the divided cooling zones Z1 and Z2, so that more strict control can be performed. Therefore, the hot rolled steel sheet H can be cooled more uniformly.

以上之實施形態中,於各分割冷卻區間Z1、Z2之個別中調整熱軋鋼板H之上面冷卻除熱量及下面冷卻除熱量之至少一方時,除溫度計40與形狀計41之測定結果外,亦可使用熱軋鋼板H之波形之傾斜度與送板速度之至少一方。此時,則藉與已參照圖9~圖12而說明之上述實施形態相同之方法而修正至少對應傾斜度或送板速度之熱軋鋼板H之溫度標準偏差Y。其次,則基於上述業經修正之溫度標準偏差Y(Y’)而修正各分割冷卻區間Z1、Z2內之熱軋鋼板H之上面冷卻除熱量及下面冷卻除熱量之至少一方。藉此,而可進而均一地冷卻熱軋鋼板H。 In the above embodiment, when at least one of the upper surface cooling heat removal amount and the lower surface cooling heat removal amount of the hot-rolled steel sheet H is adjusted in each of the divided cooling sections Z1 and Z2, the measurement results of the thermometer 40 and the shape meter 41 are also At least one of the inclination of the waveform of the hot-rolled steel sheet H and the sheet feeding speed can be used. At this time, the temperature standard deviation Y of the hot-rolled steel sheet H corresponding to at least the inclination or the sheet feeding speed is corrected by the same method as the above-described embodiment described with reference to Figs. 9 to 12 . Next, at least one of the upper surface cooling heat removal amount and the lower surface cooling heat removal amount of the hot-rolled steel sheet H in each of the divided cooling sections Z1 and Z2 is corrected based on the corrected temperature standard deviation Y (Y'). Thereby, the hot-rolled steel sheet H can be cooled uniformly.

又,依據本實施形態,熱軋鋼板H之板寬方向亦可精軋成均一之形狀及材質。圖15係顯示因表面中部波皺而於熱軋鋼板H之板寬方向上形成有振幅不同之波形之狀 態之一例者。如上所述,板寬方向上形成振幅不同之波形而於板寬方向上形成溫度標準偏差時,藉上述之本實施形態,亦可減少上述板寬方向之溫度標準偏差。 Further, according to the present embodiment, the plate width direction of the hot-rolled steel sheet H can be precisely rolled into a uniform shape and material. Fig. 15 is a view showing a waveform having a different amplitude in the width direction of the hot-rolled steel sheet H due to the wrinkles in the middle of the surface. One of the states. As described above, when a waveform having a different amplitude is formed in the sheet width direction and a temperature standard deviation is formed in the sheet width direction, the temperature standard deviation in the sheet width direction can be reduced by the above-described embodiment.

以下,則詳細說明藉送板速度之高速設定而均一冷卻熱軋鋼板H之方法。 Hereinafter, a method of uniformly cooling the hot-rolled steel sheet H in a high-speed setting of the borrowing plate speed will be described in detail.

圖16係模式地顯示另一實施形態之熱軋設備2之例者。該熱軋設備2係目的在以軋輥上下夾持已加熱之鋼胚S而連續進行輥軋,並加以軋薄至最小1.2mm再加以盤捲之設備。 Fig. 16 is a view schematically showing an example of the hot rolling facility 2 of another embodiment. This hot rolling facility 2 is intended to continuously roll a heated steel slab S up and down by a roll, and to roll it to a minimum of 1.2 mm and then coil it.

該熱軋設備2包含可加熱鋼胚S之加熱爐111、可朝寬度方向輥軋業經上述加熱爐111之加熱之鋼胚S之寬度方向輥軋機116、可自上下方向輥軋已朝上述寬度方向業經輥軋之鋼胚S而加以形成粗軋材之粗軋機112、可進而對粗軋材連續進行熱精軋至形成預定之厚度為止之精軋機113、可藉冷卻水而冷卻業經上述精軋機113之熱精軋之熱軋鋼板H之冷卻裝置114、可將業經冷卻裝置114之冷卻之熱軋鋼板H捲成鋼捲狀之盤捲裝置115。 The hot rolling facility 2 includes a heating furnace 111 capable of heating the steel preform S, a width direction rolling mill 116 capable of rolling in the width direction and being heated by the heating furnace 111, and rolling from the upper and lower directions to the above width The roughing mill 112 which forms the rough-rolled material by rolling the steel slab S, and the hot-rolling finishing of the rough-rolled material to the predetermined thickness, and the cooling mill The cooling device 114 of the hot-rolled steel sheet H of the hot-rolled steel of the rolling mill 113 can wind the hot-rolled steel sheet H cooled by the cooling device 114 into a coil-like coiling device 115.

加熱爐111配設有可對經裝入口而自外部搬入之鋼胚S噴出火焰而加熱鋼胚S之側燃燒器、軸流燃燒器、爐頂燃燒器。搬入加熱爐111內之鋼胚S則於形成在各區中之各加熱區內依序進行加熱,進而於最終區中形成之均熱區內利用爐頂燃燒器而均勻加熱鋼胚S,以進行可在最適溫度下進行輸送所需之保溫處理。加熱爐111之加熱處理全部結束後,即朝加熱爐111外輸送鋼胚S,並接續進行粗軋機112之輥軋製程。 The heating furnace 111 is provided with a side burner, an axial flow burner, and a top burner which can heat the steel preform S by ejecting a flame from a steel billet S which is carried in from the outside through the loading port. The steel slabs S carried into the heating furnace 111 are sequentially heated in the respective heating zones formed in the respective zones, and the steel slabs S are uniformly heated by the top burner in the soaking zone formed in the final zone. Perform the insulation treatment required to deliver at the optimum temperature. After the heating treatment of the heating furnace 111 is completed, the steel preform S is conveyed outside the heating furnace 111, and the rolling process of the roughing mill 112 is continued.

粗軋機112中,則使自加熱爐111送入之鋼胚S通過橫跨複數軋台而配設之圓柱狀之旋轉軋輥之間隙。舉例言之,該粗軋機112可僅藉第1軋台中配設於上下方之工作軋輥112a而對鋼胚S進行熱軋以形成粗軋材。 In the roughing mill 112, the steel blank S fed from the heating furnace 111 passes through the gap of the cylindrical rotating rolls disposed across the plurality of rolling stands. For example, the roughing mill 112 may hot-roll the steel slab S by only the work rolls 112a disposed in the upper and lower stages of the first rolling stand to form a rough rolled material.

其次,藉工作軋輥與補強軋輥所構成之複數之四重式軋機112b進而對已通過上述工作軋輥112a之粗軋材連續進行輥軋。其結果,本粗軋製程結束時,粗軋材已輥軋成厚度30~60mm程度,將再輸送至精軋機113。另,粗軋機112之構造不限於本實施形態所揭露者,軋輥數等可任意設定之。 Next, the quadruple rolling mill 112b composed of the work rolls and the reinforcing rolls is continuously rolled by the rough rolled material which has passed through the work rolls 112a. As a result, at the end of the rough rolling pass, the rough rolled material is rolled to a thickness of about 30 to 60 mm, and is again sent to the finishing mill 113. Further, the structure of the roughing mill 112 is not limited to those disclosed in the embodiment, and the number of rolls or the like can be arbitrarily set.

精軋機113則對自粗軋機112送入之粗軋材進行精軋至其厚度為數mm程度為止。該等精軋機113係使粗軋材通過橫跨6~7個軋台而排列成上下一直線之精軋輥113a之間隙,而徐緩予以加壓。業經上述精軋機113之精軋之熱軋鋼板H則藉輸送輥32(參照圖17)加以送往冷卻裝置114。另,設有上述排列成上下一直線之一對精軋輥113a之輥軋機亦稱為所謂輥軋軋台。 The finishing mill 113 finish-rolls the rough-rolled material fed from the roughing mill 112 until the thickness thereof is several mm. The finishing mills 113 are configured such that the rough-rolled material is arranged in a gap between the finishing rolls 113a of the upper and lower straight lines across 6 to 7 rolling stands, and is gradually pressurized. The hot-rolled steel sheet H subjected to the finish rolling of the finishing mill 113 is sent to the cooling device 114 by the conveying roller 32 (see Fig. 17). Further, the rolling mill provided with the above-described one of the upper and lower straight lines to the finish rolling roll 113a is also referred to as a so-called roll rolling stand.

又,橫跨6~7個軋台而排列之各精軋輥113a之間(即,輥軋台間)配置有用於進行精軋時之軋台間冷卻(輔助冷卻)之冷卻裝置142(輔助冷卻裝置)。前述冷卻裝置142之裝置構造等之詳細說明則參照圖20而留待後述。另,圖16雖已圖示於精軋機113之2部位配置有冷卻裝置142之情形,但上述冷卻裝置142亦可構成設於全部精軋輥113a之間,或僅設於其中一部分內。 Further, between each of the finishing rolls 113a arranged between 6 to 7 rolling stands (that is, between the rolling stands), a cooling device 142 (assisted cooling) for performing inter-rolling cooling (auxiliary cooling) during finish rolling is disposed. Device). The detailed description of the device structure and the like of the cooling device 142 will be described later with reference to Fig. 20 . Although FIG. 16 shows a case where the cooling device 142 is disposed in two places of the finishing mill 113, the cooling device 142 may be formed between all the finishing rolls 113a or only in a part thereof.

冷卻裝置114係用於對自精軋機113送入之熱軋 鋼板H實施層流或噴霧方式之噴嘴冷卻之設備。上述冷卻裝置114一如圖17所示,包含可對移動於滑出台之輸送輥132上之熱軋鋼板H上面自上側之冷卻口131噴射冷卻水之上側冷卻裝置114a,以及可對熱軋鋼板H下面自下側之冷卻口131噴射冷卻水之下側冷卻裝置114b。 The cooling device 114 is used for hot rolling of the self-finishing mill 113. The steel plate H is subjected to a laminar or spray nozzle cooling device. As shown in FIG. 17, the cooling device 114 includes a cooling water upper side cooling device 114a for ejecting the upper surface of the hot-rolled steel sheet H on the conveying roller 132 of the sliding table, and a hot-rolled steel plate. Below the H, the cooling water lower side cooling device 114b is sprayed from the lower side cooling port 131.

上側冷卻裝置114a及下側冷卻裝置114b個別設有複數個冷卻口131。又,冷卻口131並連接冷卻集管(圖示省略)。上述冷卻口131之個數即決定上側冷卻裝置114a及下側冷卻裝置114b之冷卻能力。另,上述冷卻裝置114亦可構成上下分流層流、層流管流、噴霧冷卻等之至少一種。 The upper cooling device 114a and the lower cooling device 114b are individually provided with a plurality of cooling ports 131. Further, the cooling port 131 is connected to a cooling header (not shown). The number of the cooling ports 131 determines the cooling capacity of the upper cooling device 114a and the lower cooling device 114b. Further, the cooling device 114 may constitute at least one of an up-and-down split layer flow, a laminar flow, and spray cooling.

上述冷卻裝置114中,調整上側冷卻裝置114a之冷卻能力與下側冷卻裝置114b之冷卻能力時,舉例言之,亦可分別就上側冷卻裝置114a之冷卻口131所連接之冷卻集管與下側冷卻裝置114b之冷卻口131所連接之冷卻集管進行開閉控制。 In the cooling device 114, when the cooling capacity of the upper cooling device 114a and the cooling capacity of the lower cooling device 114b are adjusted, for example, the cooling header and the lower side connected to the cooling port 131 of the upper cooling device 114a may be used as an example. The cooling header connected to the cooling port 131 of the cooling device 114b is opened and closed.

或,亦可控制上側冷卻裝置114a與下側冷卻裝置114b之各冷卻集管之操作參數。即,亦可調整自各冷卻口131噴出之冷卻水之水量密度、壓力、水溫之至少一種。 Alternatively, the operating parameters of the respective cooling headers of the upper side cooling device 114a and the lower side cooling device 114b may be controlled. In other words, at least one of the water amount density, the pressure, and the water temperature of the cooling water sprayed from each of the cooling ports 131 may be adjusted.

又,亦可疏減上側冷卻裝置114a與下側冷卻裝置114b之冷卻集管(冷卻口131)而調整自上側冷卻裝置114a與下側冷卻裝置114b噴射之冷卻水之流量及壓力。舉例言之,疏減冷卻集管前之上側冷卻裝置114a之冷卻能力高於下側冷卻裝置114b之冷卻能力時,宜疏減構成上側冷卻裝置114a之冷卻集管。 Further, the cooling headers (cooling ports 131) of the upper cooling device 114a and the lower cooling device 114b can be reduced to adjust the flow rate and pressure of the cooling water sprayed from the upper cooling device 114a and the lower cooling device 114b. For example, when the cooling capacity of the upper side cooling device 114a before the cooling header is reduced is higher than the cooling capacity of the lower side cooling device 114b, the cooling header constituting the upper side cooling device 114a should be reduced.

盤捲裝置115則如圖16所示,可在預定之盤捲溫度下盤捲已藉冷卻裝置114而冷卻之熱軋鋼板H。藉盤捲裝置115而捲成鋼捲狀之熱軋鋼板H將輸送至熱軋設備2外。 The coiling device 115, as shown in Fig. 16, can wind the hot-rolled steel sheet H which has been cooled by the cooling device 114 at a predetermined coil temperature. The hot-rolled steel sheet H wound into a coil shape by the coiling device 115 is sent to the outside of the hot rolling equipment 2.

構成如上之熱軋設備2之冷卻裝置114中,進行形成有表面高度(波高)在輥軋方向上變動之波形之熱軋鋼板H之冷卻時,一如上述,可適當調整上側冷卻裝置114a所噴射之冷卻水與下側冷卻裝置114b所噴射之冷卻水之水量密度、壓力、水溫等,而均一地冷卻熱軋鋼板H。然而,尤其熱軋鋼板H之送板速度較慢時,熱軋鋼板H與輸送輥132及護坦133局部接觸之時間將延長,而使熱軋鋼板H之與輸送輥132及護坦133接觸之部分因接觸除熱而容易冷卻,故將導致冷卻不均。上述冷卻之不均一性之要因則參照圖示而說明如下。 In the cooling device 114 of the hot rolling facility 2, when the hot-rolled steel sheet H having the surface height (wave height) varying in the rolling direction is cooled, the upper cooling device 114a can be appropriately adjusted as described above. The hot-rolled steel sheet H is uniformly cooled by the sprayed cooling water and the water density, pressure, water temperature, and the like of the cooling water sprayed from the lower side cooling device 114b. However, especially when the sheet feeding speed of the hot-rolled steel sheet H is slow, the time during which the hot-rolled steel sheet H is in partial contact with the conveying roller 132 and the protective 133 is prolonged, and the hot-rolled steel sheet H is brought into contact with the conveying roller 132 and the protective 133. Some of them are easily cooled by contact with heat, which results in uneven cooling. The reason for the above unevenness of cooling will be described below with reference to the drawings.

如圖18A所示,熱軋鋼板H於其輥軋方向上形成有波形時,上述熱軋鋼板H之波形之底部可能與輸送輥132局部接觸。又,如圖18B所示,沿輥軋方向而相隣之輸送輥132彼此之間可能設有作為用於避免熱軋鋼板H落入之支持體之護坦133。此時,熱軋鋼板H之波形之底部可能與輸送輥132及護坦133局部接觸。如上所述,熱軋鋼板H中與輸送輥132及護坦133局部接觸之部分亦將因接觸除熱而較其它部分更易冷卻。因此,熱軋鋼板H之冷卻將不均。 As shown in Fig. 18A, when the hot-rolled steel sheet H is formed with a wave shape in the rolling direction, the bottom of the waveform of the hot-rolled steel sheet H may be partially in contact with the conveying roller 132. Further, as shown in Fig. 18B, the adjacent conveying rollers 132 in the rolling direction may be provided with a protector 133 as a support for preventing the hot rolled steel sheet H from falling. At this time, the bottom of the waveform of the hot-rolled steel sheet H may be in partial contact with the conveying roller 132 and the protector 133. As described above, the portion of the hot-rolled steel sheet H which is in partial contact with the conveying roller 132 and the apron 133 is also more easily cooled than other portions by contact with heat. Therefore, the cooling of the hot rolled steel sheet H will be uneven.

尤其,熱軋鋼板H之送板速度為低速時,上述熱軋鋼板H與輸送輥132及護坦133局部接觸之時間將延長。其結果,如圖19A所示,熱軋鋼板H與輸送輥132及護坦133局 部接觸之部分(圖19A中虛線所圈之部分)將較其它部分更易冷卻,而使熱軋鋼板H之冷卻不均。 In particular, when the sheet feeding speed of the hot-rolled steel sheet H is low, the time during which the hot-rolled steel sheet H is partially in contact with the conveying roller 132 and the apron 133 is prolonged. As a result, as shown in FIG. 19A, the hot-rolled steel sheet H and the conveying roller 132 and the protector 133 The portion of the portion contact (the portion circled by the broken line in Fig. 19A) is more easily cooled than the other portions, and the cooling of the hot-rolled steel sheet H is uneven.

而,熱軋鋼板H之送板速度若為高速,則上述接觸時間將縮短。甚且,一旦送板速度高速化,將因熱軋鋼板H與輸送輥132及護坦133之接觸所致之斥力,而使送板中之熱軋鋼板H形成自該等輸送輥132及護坦133懸浮之狀態。 On the other hand, if the sheet feeding speed of the hot-rolled steel sheet H is high, the above contact time will be shortened. Further, once the sheet feeding speed is increased, the reflow force due to the contact between the hot-rolled steel sheet H and the conveying roller 132 and the protector 133 is made, and the hot-rolled steel sheet H in the sheet is formed from the conveying rollers 132 and protected. Tan 133 suspension state.

又,熱軋鋼板H之送板速度一旦高速化,將因上述接觸所致之斥力而使熱軋鋼板H形成自輸送輥132及護坦133懸浮之狀態,並將減少熱軋鋼板H與輸送輥132及護坦133之接觸時間及接觸次數,故上述接觸所致之降溫將減少至可加以忽略之程度。 When the sheet feeding speed of the hot-rolled steel sheet H is increased, the hot-rolled steel sheet H is suspended from the conveying roller 132 and the apron 133 due to the repulsive force caused by the contact, and the hot-rolled steel sheet H and the conveying are reduced. The contact time and the number of contacts of the roller 132 and the protector 133 are reduced, so that the temperature drop caused by the above contact is reduced to such an extent that it can be ignored.

因此,可使送板速度高速化而抑制接觸除熱,並如圖19B所示而更為均一地冷卻熱軋鋼板H。其次,發明人等人已發現將上述送板速度設為550m/min以上,即可充分均一地冷卻熱軋鋼板H。 Therefore, the sheet feeding speed can be increased, the contact heat removal can be suppressed, and the hot-rolled steel sheet H can be more uniformly cooled as shown in Fig. 19B. Then, the inventors have found that the hot-rolled steel sheet H can be sufficiently uniformly cooled by setting the sheet feeding speed to 550 m/min or more.

另,上述發現係得自形成波形之熱軋鋼板H之冷卻,但不拘上述波形之高度,熱軋鋼板H之最低點將接觸輸送輥132及護坦133,故不拘波形之高度而使送板速度高速化,即可有效進行均一之冷卻。 Further, the above findings are obtained by cooling the hot-rolled steel sheet H which forms the waveform, but regardless of the height of the waveform, the lowest point of the hot-rolled steel sheet H will contact the conveying roller 132 and the apron 133, so the plate feeding speed is not limited to the height of the waveform. With high speed, uniform cooling can be effectively performed.

又,若將熱軋鋼板H之送板速度設在550m/min以上,將使熱軋鋼板H形成自輸送輥132及護坦133懸浮之狀態,故即便在該狀態下朝熱軋鋼板H噴射冷卻水,亦可如習知般避免熱軋鋼板H上存在積水。因此,可避免因積水而使熱軋鋼板H之冷卻不均。 In addition, when the sheet feeding speed of the hot-rolled steel sheet H is set to 550 m/min or more, the hot-rolled steel sheet H is formed in a state in which the conveying roller 132 and the apron 133 are suspended, so that the hot-rolled steel sheet H is ejected even in this state. Cooling water can also prevent the presence of accumulated water on the hot rolled steel sheet H as is conventional. Therefore, it is possible to avoid uneven cooling of the hot-rolled steel sheet H due to the accumulation of water.

如上所述,除前述之上下面除熱量控制以外,並將冷卻區間內之熱軋鋼板H之送板速度設在550m/min以上,即可更為均一地冷卻具有波高在輥軋方向上周期地變動之波形之熱軋鋼板H。 As described above, in addition to the above-described upper and lower heat removal control, and the sheet feeding speed of the hot-rolled steel sheet H in the cooling section is set to 550 m/min or more, the cooling can be more uniformly cooled with the wave height in the rolling direction. Hot-rolled steel sheet H of the waveform of the ground change.

另,熱軋鋼板H之送板速度雖愈高速愈佳,但無法超越機械性極限速度(諸如1550m/min)。因此,實質上,冷卻區間內之熱軋鋼板H之送板速度將設在550m/min以上至機械性極限速度以下之範圍內。且,已預設實際操作時之送板速度之上限值(操作上限速度)時,熱軋鋼板H之送板速度則宜設在550m/min以上至操作上限速度(諸如1200m/min)以下之範圍內。 In addition, the hot plate steel H has a higher plate speed, but it cannot exceed the mechanical limit speed (such as 1550 m/min). Therefore, in essence, the sheet feeding speed of the hot-rolled steel sheet H in the cooling section is set to be in the range of 550 m/min or more to the mechanical limit speed. Moreover, when the upper limit of the plate feeding speed (operating upper limit speed) in the actual operation is preset, the plate feeding speed of the hot rolled steel sheet H is preferably set to be above 550 m/min to the upper limit operating speed (such as 1200 m/min). Within the scope.

當然,亦可就已參照圖1~圖14而說明之熱軋鋼板冷卻方法追加送板速度之高速設定(設在550m/min以上至機械性極限速度以下之範圍內)。 Needless to say, the hot-rolled steel sheet cooling method described with reference to FIGS. 1 to 14 may be added at a high speed setting (provided in a range from 550 m/min or more to a mechanical limit speed).

又,一般而言,已知若為拉伸強度較大之熱軋鋼板H(尤其拉伸強度(TS)為800MPa以上,實際上以1400MPa為上限之稱為所謂高張力之鋼板等),上述熱軋鋼板H之高硬度所導致熱軋設備2之輥軋時產生之加工發熱較多。因此,迄今係藉降低冷卻裝置114(即冷卻區間)內之熱軋鋼板H之送板速度以充分進行冷卻。 In addition, it is generally known that the hot-rolled steel sheet H having a large tensile strength (especially a steel sheet having a tensile strength (TS) of 800 MPa or more and actually having an upper limit of 1400 MPa is called a high-strength steel sheet) The high hardness of the hot-rolled steel sheet H causes a large amount of heat generated during the rolling of the hot rolling equipment 2. Therefore, the sheet feeding speed of the hot-rolled steel sheet H in the cooling device 114 (i.e., the cooling zone) has been reduced so far to sufficiently cool.

然而,一旦降低冷卻裝置114內之熱軋鋼板H之送板速度,則熱軋鋼板H形成有波形時,將如上述般因熱軋鋼板H與輸送輥132及護坦133局部接觸,導致接觸部分因接觸除熱而容易冷卻,而發生不均一之冷卻。 However, when the sheet feeding speed of the hot-rolled steel sheet H in the cooling device 114 is lowered, when the hot-rolled steel sheet H is formed with a wave shape, the hot-rolled steel sheet H is partially in contact with the conveying roller 132 and the apron 133 as described above, resulting in contact. Part of the cooling is easy due to contact with heat, and uneven cooling occurs.

因此,本案發明人等人發現於熱軋設備2之精軋機113中,在諸如橫跨6~7個軋台而設之一對精軋輥113a(即輥軋台)彼此之間進行冷卻(所謂軋台間冷卻),即可抑制上述加工發熱,並將冷卻裝置114內之熱軋鋼板H之送板速度設為550m/min以上。以下,即參照圖20而說明上述之軋台間冷卻。 Therefore, the inventors of the present invention have found that in the finishing mill 113 of the hot rolling facility 2, one pair of finishing rolls 113a (i.e., rolling stations), such as across 6 to 7 rolling stands, are cooled to each other (so-called By cooling between the rolling stands, the above-described processing heat can be suppressed, and the sheet feeding speed of the hot-rolled steel sheet H in the cooling device 114 is set to 550 m/min or more. Hereinafter, the above-described inter-rolling table cooling will be described with reference to Fig. 20 .

圖20係可進行軋台間冷卻之精軋機113之說明圖,為利於說明而放大精軋機113之局部,並圖示3個輥軋台。另,圖20中,與上述實施形態相同之構成要素附有相同之標號。如圖20所示,精軋機113設有複數包括排列成上下一直線之一對精軋輥113a等(圖20中為3個)之輥軋台140。各輥軋台140彼此之間設有作為用於實施層流或噴霧方式之噴嘴冷卻之設備之冷卻裝置142,而可於輥軋台140彼此間對熱軋鋼板H進行軋台間冷卻。 Fig. 20 is an explanatory view of a finishing mill 113 capable of performing inter-rolling cooling, and a part of the finishing mill 113 is enlarged for the sake of explanation, and three rolling stands are illustrated. In FIG. 20, the same components as those of the above-described embodiment are denoted by the same reference numerals. As shown in Fig. 20, the finishing mill 113 is provided with a plurality of rolling stands 140 including one of the upper and lower straight lines, the finishing rolls 113a and the like (three in Fig. 20). Each of the rolling stands 140 is provided with a cooling device 142 as a device for performing nozzle cooling of a laminar flow or a spray method, and the hot-rolled steel sheet H can be cooled between the rolling stands 140.

上述冷卻裝置142一如圖20所示,包含可對輸送於精軋機113中之熱軋鋼板H藉冷卻口146而自上側噴出冷卻水之上側冷卻裝置142a,以及可對熱軋鋼板H下面自下側噴出冷卻水之下側冷卻裝置142b。上側冷卻裝置142a及下側冷卻裝置142b個別設有複數個冷卻口146。且,冷卻口146並連接冷卻集管(圖示省略)。另,上述冷卻裝置142亦可構成上下分流層流、層流管流、噴霧冷卻等之至少一種。 As shown in FIG. 20, the cooling device 142 includes a cooling water upper side cooling device 142a for discharging the hot-rolled steel sheet H conveyed in the finishing mill 113 from the upper side, and a hot-rolled steel sheet H. The lower side discharges the cooling water lower side cooling device 142b. The upper cooling device 142a and the lower cooling device 142b are individually provided with a plurality of cooling ports 146. Further, the cooling port 146 is connected to a cooling header (not shown). Further, the cooling device 142 may constitute at least one of an up-and-down split layer flow, a laminar flow, and spray cooling.

構成如圖20所示之精軋機113中,尤其當熱軋鋼板H之拉伸強度(TS)為800MPa以上時,可藉進行軋台間冷卻而抑制熱軋鋼板H之加工發熱。藉此,即可將冷卻裝置114 中之熱軋鋼板H之送板速度保持為550m/min以上。因此,可解決以往在低速之送板速度下進行冷卻時造成問題之熱軋鋼板H與輸送輥132及護坦133之局部接觸所導致接觸部分因接觸除熱而容易冷卻之困擾,而可充分均一地冷卻熱軋鋼板H。 In the finishing mill 113 shown in FIG. 20, in particular, when the tensile strength (TS) of the hot-rolled steel sheet H is 800 MPa or more, it is possible to suppress the heat generation of the hot-rolled steel sheet H by performing cooling between the rolling stands. Thereby, the cooling device 114 can be In the hot-rolled steel sheet H, the sheet feeding speed is maintained at 550 m/min or more. Therefore, it is possible to solve the problem that the contact portion of the hot-rolled steel sheet H which is problematic in cooling at a low-speed sheet feeding speed and the conveying roller 132 and the protector 133 is easily cooled by contact with heat, and can be sufficiently The hot rolled steel sheet H is uniformly cooled.

以上之實施形態中,冷卻裝置114對熱軋鋼板H進行之冷卻宜在該熱軋鋼板H之溫度為600℃以上之範圍內進行。熱軋鋼板H之溫度為600℃以上之溫度領域即所謂膜態沸騰領域。即,此時,可避開所謂變態沸騰領域而在膜態沸騰領域中冷卻熱軋鋼板H。變態沸騰領域中,朝熱軋鋼板H之表面噴射冷卻水後,該熱軋鋼板H之表面上將併存為蒸氣膜所覆蓋之部分,以及冷卻水對熱軋鋼板H直接噴射之部分。因此,無法均一地冷卻熱軋鋼板H。 In the above embodiment, the cooling of the hot-rolled steel sheet H by the cooling device 114 is preferably carried out in a range in which the temperature of the hot-rolled steel sheet H is 600 °C or higher. The temperature range of the hot-rolled steel sheet H is 600 ° C or higher, which is the so-called film boiling field. That is, at this time, the hot-rolled steel sheet H can be cooled in the film-state boiling region while avoiding the so-called metamorphic boiling field. In the field of the abnormal boiling, after the cooling water is sprayed onto the surface of the hot-rolled steel sheet H, the surface of the hot-rolled steel sheet H is coexisted as a portion covered by the vapor film, and a portion where the cooling water is directly sprayed on the hot-rolled steel sheet H. Therefore, the hot rolled steel sheet H cannot be uniformly cooled.

另,膜態沸騰領域中,則在熱軋鋼板H之表面整體為蒸氣膜所覆蓋之狀態下進行熱軋鋼板H之冷卻,故可均一地冷卻熱軋鋼板H。因此,可如本實施形態般,在熱軋鋼板H之溫度為600℃以上之範圍內更為均一地冷卻熱軋鋼板H。 Further, in the field of film boiling, the hot-rolled steel sheet H is cooled in a state where the entire surface of the hot-rolled steel sheet H is covered with a vapor film, so that the hot-rolled steel sheet H can be uniformly cooled. Therefore, as in the present embodiment, the hot-rolled steel sheet H can be more uniformly cooled in the range of the temperature of the hot-rolled steel sheet H of 600 ° C or more.

以上,已參照附圖而說明本發明之較佳實施形態,但本發明不受限於上述實施形態。凡本技術領域之從業人員自當可在申請專利範圍所揭露之思想範疇內構思各種變更例或修正例,其等則當然應理解為包含於本發明之技術範圍內。 The preferred embodiments of the present invention have been described above with reference to the drawings, but the present invention is not limited to the embodiments described above. It is to be understood that those skilled in the art can devise various modifications and alterations within the scope of the invention as disclosed in the appended claims.

【實施例】 [Examples]

本案發明人為驗證將熱軋鋼板之送板速度設為 550m/min以上,即可進行熱軋鋼板之均一冷卻,而進行了熱軋鋼板之冷卻實驗作為實施例。 The inventor of the present invention verified that the plate feeding speed of the hot rolled steel sheet was set. At 550 m/min or more, uniform cooling of the hot-rolled steel sheet can be performed, and a cooling test of the hot-rolled steel sheet is carried out as an example.

(第1實施例) (First embodiment)

已就板厚2.5mm、寬1200mm、拉伸強度400MPa及傾斜度2%之形成有中波之熱軋鋼板,改變在冷卻裝置內之送板速度而進行冷卻。具體而言,係將送板速度變更為400m/min、450m/min、500m/min、550m/min、600m/min、650m/min,而就各種送板速度下之熱軋鋼板之冷卻各進行20次。 A hot-rolled steel sheet having a medium wave having a thickness of 2.5 mm, a width of 1200 mm, a tensile strength of 400 MPa, and a slope of 2% has been formed, and the sheet feeding speed in the cooling device is changed to be cooled. Specifically, the sheet feeding speed is changed to 400 m/min, 450 m/min, 500 m/min, 550 m/min, 600 m/min, and 650 m/min, and each of the cooling of the hot-rolled steel sheets at various sheet feeding speeds is performed. 20 times.

其次,測定盤捲時之熱軋鋼板之溫度,再使用其溫度測定結果算出溫度變動之標準偏差之平均值(CT溫度變動量)。就上述算出之CT溫度變動量進行評價之結果則顯示於以下之表3。另,評價基準係在CT溫度變動量大於25℃時評為並未均一冷卻,而在CT溫度變動量為25℃以下時,評為已均一冷卻。 Next, the temperature of the hot-rolled steel sheet at the time of coiling was measured, and the average value (CT temperature fluctuation amount) of the standard deviation of the temperature fluctuation was calculated using the temperature measurement result. The results of the evaluation of the CT temperature fluctuation amount calculated above are shown in Table 3 below. In addition, the evaluation criteria were evaluated as having no uniform cooling when the CT temperature variation amount was greater than 25 ° C, and were rated as uniform cooling when the CT temperature fluctuation amount was 25 ° C or less.

如表5所示,送板速度為500m/min以下時,CT溫度變動量並未充分減少(高於25℃),而未充分進行熱軋鋼板之均一冷卻。而,送板速度為550m/min以上時,CT溫度變 動量則降至25℃以下,可知已進行熱軋鋼板之均一冷卻。另,尤其送板速度為600m/min以上時,CT溫度則降至未滿10℃(8℃、6℃),故可知該條件更適於實現熱軋鋼板之均一冷卻。 As shown in Table 5, when the sheet feeding speed was 500 m/min or less, the amount of change in the CT temperature was not sufficiently reduced (above 25 ° C), and uniform cooling of the hot-rolled steel sheet was not sufficiently performed. However, when the plate feeding speed is 550 m/min or more, the CT temperature changes. The momentum is reduced to below 25 ° C, and it is known that the uniform cooling of the hot rolled steel sheet has been performed. In addition, especially when the sheet feeding speed is 600 m/min or more, the CT temperature is lowered to less than 10 ° C (8 ° C, 6 ° C), so that this condition is more suitable for achieving uniform cooling of the hot rolled steel sheet.

(第2實施形態) (Second embodiment)

已就板厚2.5mm、寬1200mm、拉伸強度800MPa及傾斜度2%之形成有中波之熱軋鋼板進行軋台間冷卻以使精軋之出口側溫度降至880℃,並變更冷卻裝置中之送板速度而進行冷卻。具體而言,係將送板速度變更為400m/min、450m/min、500m/min、550m/min、600m/min、650m/min,而就各種送板速度下之熱軋鋼板之冷卻各進行20次。 The hot-rolled steel sheet having a medium thickness of 2.5 mm, a width of 1200 mm, a tensile strength of 800 MPa, and a slope of 2% has been subjected to inter-rolling cooling to reduce the outlet side temperature of the finish rolling to 880 ° C, and the cooling device is changed. The board is cooled in speed. Specifically, the sheet feeding speed is changed to 400 m/min, 450 m/min, 500 m/min, 550 m/min, 600 m/min, and 650 m/min, and each of the cooling of the hot-rolled steel sheets at various sheet feeding speeds is performed. 20 times.

其次,測定盤捲時之熱軋鋼板之溫度,並使用其溫度測定結果而算出溫度變動之標準偏差之平均值(CT溫度變動量)。就上述算出之CT溫度變動量進行評價之結果則顯示於以下之表4。另,評價基準與上述第1實施例相同,僅在送板速度400m/min時未進行軋台間冷卻。 Next, the temperature of the hot-rolled steel sheet at the time of coiling was measured, and the average value (CT temperature fluctuation amount) of the standard deviation of the temperature fluctuation was calculated using the temperature measurement result. The results of the evaluation of the CT temperature fluctuation amount calculated above are shown in Table 4 below. Further, the evaluation criteria were the same as in the above-described first embodiment, and cooling between the rolling stands was not performed only at the sheet feeding speed of 400 m/min.

如表6所示,送板速度在500m/min以下時,即便進行了軋台間冷卻,亦未充分減少CT溫度變動量(高於 25℃),而未充行進行熱軋鋼板之均一冷卻。另,送板速度為550m/min以上時,CT溫度變動量已降至25℃以下,可知已進行熱軋鋼板之均一冷卻。 As shown in Table 6, when the sheet feeding speed is 500 m/min or less, the CT temperature fluctuation amount is not sufficiently reduced even if the inter-rolling table cooling is performed (higher than 25 ° C), while the uniform cooling of the hot rolled steel sheet was not carried out. Further, when the sheet feeding speed was 550 m/min or more, the amount of change in the CT temperature was lowered to 25 ° C or less, and it was found that the uniform cooling of the hot-rolled steel sheet was performed.

又,進行軋台間冷卻後(即表6所示之情形),硬度較高(拉伸強度800MPa)之熱軋鋼板亦可減少CT溫度變動量。即,可知使熱軋鋼板之冷卻時之送板速度為550m/min以上,並實施精軋機中之軋台間輥軋,即可對所有鋼材尤其硬度較高之鋼材亦進行均一之冷卻。 Further, after cooling between the rolling stands (that is, as shown in Table 6), the hot-rolled steel sheet having a high hardness (tensile strength of 800 MPa) can also reduce the amount of variation in CT temperature. In other words, it is understood that the hot plate rolling speed at the time of cooling of the hot-rolled steel sheet is 550 m/min or more, and rolling between the rolling mills in the finishing mill is performed, so that all the steel materials, particularly those having a high hardness, can be uniformly cooled.

產業上之可利用性 Industrial availability

本發明適用於業經精軋機之熱軋,並形成有表面高度在輥軋方向上變動之波形之熱軋鋼板之冷卻。 The present invention is applicable to the hot rolling of a finishing mill and the formation of a hot rolled steel sheet having a waveform whose surface height fluctuates in the rolling direction.

Claims (17)

一種熱軋鋼板冷卻方法,係將業經精軋機熱軋之熱軋鋼板在設於其送板路徑上之冷卻區間中加以冷卻,其特徵在於包含以下步驟:目標比率設定步驟,基於預先實驗性地在使前述熱軋鋼板之傾斜度及送板速度為一定值之條件下預先求出之、代表前述熱軋鋼板之上下面之導熱係數之比率之上下導熱係數比率X與前述熱軋鋼板之冷卻中或冷卻後之溫度標準偏差Y之相關關係之相關資料,而將前述溫度標準偏差Y為最小值Ymin之上下導熱係數比率X1設定為目標比率Xt;及冷卻控制步驟,控制前述冷卻區間內之前述熱軋鋼板之上面冷卻除熱量與下面冷卻除熱量之至少一方,以使前述冷卻區間內之前述熱軋鋼板之上下導熱係數比率X與前述目標比率Xt一致。 A method for cooling a hot-rolled steel sheet, wherein a hot-rolled steel sheet which has been hot-rolled by a finishing mill is cooled in a cooling section provided on a feeding path thereof, comprising the following steps: a target ratio setting step based on preliminary experimentally The thermal conductivity ratio X above the ratio of the thermal conductivity of the upper and lower sides of the hot-rolled steel sheet and the cooling of the hot-rolled steel sheet are obtained in advance, under the condition that the inclination of the hot-rolled steel sheet and the sheet feeding speed are constant. The correlation data of the temperature standard deviation Y in the middle or after cooling, and the thermal conductivity coefficient ratio X1 above the minimum temperature Ymin is set as the target ratio Xt; and the cooling control step controls the cooling interval At least one of the upper surface of the hot-rolled steel sheet and the heat-dissipating heat and the heat-removing heat is cooled so that the thermal conductivity ratio X of the hot-rolled steel sheet in the cooling zone is equal to the target ratio Xt. 如申請專利範圍第1項之熱軋鋼板冷卻方法,其中於前述目標比率設定步驟中,係基於前述相關資料,而將可將前述溫度標準偏差Y控制在最小值Ymin至最小值Ymin+10℃以內之範圍內之上下導熱係數比率X設定為前述目標比率Xt。 The method for cooling a hot-rolled steel sheet according to claim 1, wherein in the foregoing target ratio setting step, the temperature standard deviation Y is controlled to a minimum value Ymin to a minimum value Ymin+10°C based on the aforementioned related information. The thermal conductivity ratio X above and below the range is set to the aforementioned target ratio Xt. 如申請專利範圍第1或2項之熱軋鋼板冷卻方法,其中前述相關資料是就前述傾斜度及前述送板速度之值不同之複數條件個別準備, 前述目標比率設定步驟中,則基於前述複數之相關資料內對應前述傾斜度及前述送板速度之實測值之相關資料,而設定前述目標比率Xt。 The method for cooling a hot-rolled steel sheet according to claim 1 or 2, wherein the related information is separately prepared for a plurality of conditions in which the values of the inclination and the plate feeding speed are different, In the target ratio setting step, the target ratio Xt is set based on the correlation data corresponding to the measured value of the inclination and the plate feeding speed in the correlation data of the plurality of numbers. 如申請專利範圍第3項之熱軋鋼板冷卻方法,其中前述相關資料係以迴歸公式顯示前述上下導熱係數比率X與前述溫度標準偏差Y之相關關係之資料。 The method for cooling a hot-rolled steel sheet according to item 3 of the patent application, wherein the aforementioned related data is a data showing a correlation between the upper and lower thermal conductivity ratio X and the temperature standard deviation Y by a regression formula. 如申請專利範圍第4項之熱軋鋼板冷卻方法,其中前述迴歸公式係藉線性迴歸而導出者。 For example, in the hot-rolled steel sheet cooling method of claim 4, the foregoing regression formula is derived by linear regression. 如申請專利範圍第3項之熱軋鋼板冷卻方法,其中前述相關資料係以表格顯示前述上下導熱係數比率X與前述溫度標準偏差Y之相關關係之資料。 The method for cooling a hot-rolled steel sheet according to item 3 of the patent application, wherein the related information is a table showing data on the correlation between the upper and lower thermal conductivity ratios X and the temperature standard deviation Y. 如申請專利範圍第1或2項之熱軋鋼板冷卻方法,其更具有以下步驟:溫度測定步驟,依時間序列而測定前述冷卻區間之下游側之前述熱軋鋼板之溫度;溫度平均值算出步驟,基於前述溫度之測定結果而算出前述溫度之時間序列平均值;及冷卻除熱量調整步驟,調整前述冷卻區間內之前述熱軋鋼板之前述上面冷卻除熱量與前述下面冷卻除熱量之合計值,以使前述溫度之時間序列平均值與預定之目標溫度一致。 The hot-rolled steel sheet cooling method according to claim 1 or 2, further comprising the step of: measuring a temperature of the hot-rolled steel sheet on a downstream side of the cooling section in a time series according to a time series; and calculating a temperature average value And calculating a time-series average value of the temperature based on the measurement result of the temperature; and a cooling and heat removal adjustment step of adjusting a total value of the upper surface cooling heat removal amount and the lower surface cooling heat removal amount of the hot-rolled steel sheet in the cooling section, The time series average of the aforementioned temperatures is made to coincide with the predetermined target temperature. 如申請專利範圍第1或2項之熱軋鋼板冷卻方法,其更具有以下步驟:溫度測定步驟,依時間序列而測定前述冷卻區間之 下游側之前述熱軋鋼板之溫度;變動速度測定步驟,依時間序列而測定與前述冷卻區間之下游側之前述熱軋鋼板之溫度測定部位相同之部位上之前述熱軋鋼板之垂直方向之變動速度;控制方向決定步驟,在以前述熱軋鋼板之垂直方向之上方為正值時,於前述變動速度為正值之領域內,前述熱軋鋼板之溫度相對於前述熱軋鋼板之波形1周期以上之範圍之平均溫度而較低時,將前述上面冷卻除熱量減少之方向及前述下面冷卻除熱量增加之方向之至少一方決定為控制方向,並在前述熱軋鋼板之溫度相對於前述平均溫度而較高時,將前述上面冷卻除熱量增加之方向及前述下面冷卻除熱量減少之方向之至少一方決定為前述控制方向,並於前述變動速度為負值之領域內,在前述熱軋鋼板之溫度相對於前述平均溫度而較低時,將前述上面冷卻除熱量增加之方向及前述下面冷卻除熱量減少之方向之至少一方決定為前述控制方向,並在前述熱軋鋼板之溫度相對於前述平均溫度而較高時,將前述上面冷卻除熱量減少之方向及前述下面冷卻除熱量增加之方向之至少一方決定為前述控制方向;及冷卻除熱量調整步驟,基於前述控制方向決定步驟中已決定之前述控制方向,而調整前述冷卻區間內之前述熱軋鋼板之前述上面冷卻除熱量及前述下面冷卻除熱量之至少一方。 The hot-rolled steel sheet cooling method according to claim 1 or 2, further comprising the steps of: measuring a temperature, and measuring the cooling interval according to a time series a temperature of the hot-rolled steel sheet on the downstream side; a fluctuation speed measuring step of measuring a vertical direction of the hot-rolled steel sheet at a portion of the same portion as a temperature-measuring portion of the hot-rolled steel sheet on the downstream side of the cooling section in a time series a speed; a control direction determining step, wherein a temperature of the hot-rolled steel sheet is 1 cycle with respect to a waveform of the hot-rolled steel sheet in a field in which the fluctuation speed is a positive value when a positive value is above a vertical direction of the hot-rolled steel sheet When the average temperature of the above range is low, at least one of the direction in which the cooling and heat removal is reduced and the direction in which the cooling and heat removal in the lower surface are increased is determined as the control direction, and the temperature of the hot-rolled steel sheet is relative to the average temperature. When it is high, at least one of the direction in which the above-described cooling and heat removal is increased and the direction in which the cooling and heat removal is reduced is determined as the control direction, and in the field where the fluctuation speed is a negative value, in the hot-rolled steel sheet. When the temperature is lower than the average temperature, the direction of the above cooling and heat removal is increased and the front At least one of the directions of cooling and heat removal reduction is determined as the control direction, and when the temperature of the hot-rolled steel sheet is higher than the average temperature, the direction of the above-described cooling and heat removal is reduced and the heat is removed by the lower surface. At least one of the increasing directions is determined as the control direction; and the cooling and heat removal adjusting step adjusts the aforementioned upper cooling heat removal amount of the hot-rolled steel sheet in the cooling interval based on the control direction determined in the control direction determining step And at least one of the foregoing cooling and heat removal. 如申請專利範圍第8項之熱軋鋼板冷卻方法,其中前述 冷卻區間係沿前述熱軋鋼板之送板方向而分割成複數之分割冷卻區間,前述溫度測定步驟及前述變動速度測定步驟中,就前述分割冷卻區間之邊界個別依時間序列而測定前述熱軋鋼板之溫度及變動速度,前述控制方向決定步驟中,則基於前述分割冷卻區間之邊界個別之前述熱軋鋼板之溫度及變動速度之測定結果,而就前述分割冷卻區間個別決定前述熱軋鋼板之上下面之冷卻除熱量之增減方向,前述冷卻除熱量調整步驟中,則基於已就前述分割冷卻區間個別而決定之前述控制方向進行回饋控制或前饋控制,以就前述分割冷卻區間個別調整前述熱軋鋼板之前述上面冷卻除熱量及前述下面冷卻除熱量之至少一方。 A method for cooling a hot rolled steel sheet according to item 8 of the patent application, wherein the aforementioned The cooling zone is divided into a plurality of divided cooling sections along the sheet feeding direction of the hot-rolled steel sheet, and in the temperature measuring step and the fluctuation speed measuring step, the hot-rolled steel sheet is individually measured in time series with respect to the boundary of the divided cooling section. The temperature and the fluctuation speed, in the control direction determining step, the measurement result of the temperature and the fluctuation speed of the hot-rolled steel sheet which are individual on the boundary between the divided cooling sections, and the above-mentioned divided cooling section is individually determined on the hot-rolled steel sheet In the cooling and heat removal adjustment step, the cooling and heat removal adjustment step performs feedback control or feedforward control based on the control direction that has been determined for each of the divided cooling sections, and individually adjusts the aforementioned divided cooling sections. At least one of the above-described upper cooling heat removal heat and the lower cooling heat removal heat of the hot-rolled steel sheet. 如申請專利範圍第9項之熱軋鋼板冷卻方法,其更具有以下步驟:測定步驟,就前述分割冷卻區間之邊界個別測定前述熱軋鋼板之前述傾斜度或前述送板速度;及冷卻除熱量修正步驟,基於前述傾斜度或前述送板速度之測定結果,而修正前述分割冷卻區間個別之前述熱軋鋼板之前述上面冷卻除熱量及前述下面冷卻除熱量之至少一方。 The method for cooling a hot-rolled steel sheet according to claim 9 further comprises the steps of: measuring the aforementioned inclination of the hot-rolled steel sheet or the feeding speed of the hot-rolled steel sheet at a boundary of the divided cooling section; and cooling and removing heat The correction step corrects at least one of the upper surface cooling heat removal amount and the lower surface cooling heat removal amount of the hot-rolled steel sheet in the divided cooling section based on the measurement result of the inclination or the sheet feeding speed. 如申請專利範圍第1或2項之熱軋鋼板冷卻方法,其更具有後冷卻步驟,係於前述冷卻區間之下游側進而冷卻前 述熱軋鋼板,以使前述熱軋鋼板之溫度標準偏差在可容許之範圍內。 The hot-rolled steel sheet cooling method according to claim 1 or 2, further comprising a post-cooling step, which is on the downstream side of the cooling section and then cooled The hot-rolled steel sheet is described such that the temperature standard deviation of the hot-rolled steel sheet is within an allowable range. 如申請專利範圍第1或2項之熱軋鋼板冷卻方法,其中於前述冷卻區間內之前述熱軋鋼板之送板速度設在550m/min以上至機械性極限速度以下之範圍內。 The hot-rolled steel sheet cooling method according to claim 1 or 2, wherein the sheet feeding speed of the hot-rolled steel sheet in the cooling section is set to be in a range from 550 m/min or more to a mechanical limit speed. 如申請專利範圍第12項之熱軋鋼板冷卻方法,其中前述熱軋鋼板之拉伸強度為800MPa以上。 The hot-rolled steel sheet cooling method according to claim 12, wherein the hot-rolled steel sheet has a tensile strength of 800 MPa or more. 如申請專利範圍第12項之熱軋鋼板冷卻方法,其中前述精軋機係由複數之輥軋台所構成,本方法更包含輔助冷卻步驟,係於前述複數之輥軋台彼此之間進行前述熱軋鋼板之輔助冷卻。 The hot-rolled steel sheet cooling method according to claim 12, wherein the finishing mill is composed of a plurality of rolling stations, and the method further comprises an auxiliary cooling step of performing the aforementioned hot rolling between the plurality of rolling stations. Auxiliary cooling of the steel plate. 如申請專利範圍第1或2項之熱軋鋼板冷卻方法,其中前述冷卻區間中設有具有可朝前述熱軋鋼板上面噴射冷卻水之複數集管之上側冷卻裝置,以及具有可朝前述熱軋鋼板下面噴射冷卻水之複數集管之下側冷卻裝置,前述上面冷卻除熱量及前述下面冷卻除熱量可藉將前述各集管開閉控制而進行調整。 The hot-rolled steel sheet cooling method according to claim 1 or 2, wherein the cooling section is provided with a plurality of header upper side cooling means capable of injecting cooling water onto the hot-rolled steel sheet, and having a hot rolling direction A lower header cooling device that sprays cooling water under the steel plate, and the above-described upper cooling and heat removal and the lower cooling and heat removal can be adjusted by opening and closing the respective headers. 如申請專利範圍第1或2項之熱軋鋼板冷卻方法,其中在前述冷卻區間中設有具有可朝前述熱軋鋼板上面噴射冷卻水之複數集管之上側冷卻裝置,以及具有可朝前述熱軋鋼板下面噴射冷卻水之複數集管之下側冷卻裝置,前述上面冷卻除熱量及前述下面冷卻除熱量可藉控制前述各集管之水量密度、壓力及水溫之至少一種而進行調整。 The hot-rolled steel sheet cooling method according to the first or second aspect of the invention, wherein the cooling section is provided with a plurality of header upper side cooling means capable of injecting cooling water onto the hot-rolled steel sheet, and having a heat toward the foregoing The lower side cooling device of the plurality of headers for injecting the cooling water under the rolled steel plate, the above-mentioned upper cooling and heat removal and the lower cooling and heat removal can be adjusted by controlling at least one of the water density, the pressure and the water temperature of the respective headers. 如申請專利範圍第1或2項之熱軋鋼板冷卻方法,其中前述冷卻區間中之冷卻係在前述熱軋鋼板之溫度為600℃以上之範圍內進行。 The method for cooling a hot-rolled steel sheet according to claim 1 or 2, wherein the cooling in the cooling section is performed in a range in which the temperature of the hot-rolled steel sheet is 600 ° C or more.
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