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1、<p><b>  中厚板軋機(jī)的自動(dòng)化</b></p><p>  1978年配置新的主傳動(dòng)裝置的一新的寬厚板軋機(jī)杜伊斯堡進(jìn)入運(yùn)行。這個(gè)新的寬厚板軋機(jī)重360噸、支承輥直徑為2100毫米,寬度只有3.7米,這個(gè)新的寬厚板軋機(jī)極為堅(jiān)固,而且也是歐洲第一個(gè)配備液壓厚度控制和過程計(jì)算機(jī)控制的厚板軋機(jī)。然而,隨著激光焊接技術(shù)在板材加工上的應(yīng)用和使用移動(dòng)式起重機(jī)建設(shè)增加負(fù)載能力,已導(dǎo)致軋機(jī)的

2、標(biāo)準(zhǔn)越來越高,來要求厚板產(chǎn)品的平整度和厚度公差。因此,需要裝配新的液壓工作輥彎曲設(shè)備,密集的冷卻系統(tǒng),并不斷調(diào)整和優(yōu)化計(jì)算機(jī)模型,通過這些不斷改進(jìn)才能得以達(dá)到上述要求。不過,限制了原來的電腦系統(tǒng),最終成為一個(gè)將來發(fā)展的障礙。 </p><p>  從1999年開始進(jìn)行了廣泛的現(xiàn)代化計(jì)劃,其中包括新的控制系統(tǒng)、加熱爐、現(xiàn)代化的液壓系統(tǒng)等,被稱為現(xiàn)代化軋鋼過程計(jì)算機(jī)化。這包括基礎(chǔ)自動(dòng)化(一級(jí)),即輥式搖床和側(cè)面導(dǎo)板、

3、機(jī)電液壓調(diào)節(jié)系統(tǒng)、主傳動(dòng)裝置、工作輥撓度,中間冷卻、密集的冷卻系統(tǒng)組成的最終冷卻為,以及完整的第二級(jí)物料跟蹤系統(tǒng),能量和過程的數(shù)據(jù)處理,第3級(jí)為儀表,爐模型和預(yù)測(cè)模型及穩(wěn)定的軋制過程。 </p><p>  為了能夠盡可能平穩(wěn)過渡到新的電腦系統(tǒng), 一個(gè)復(fù)雜的轉(zhuǎn)接系統(tǒng)安裝后, 應(yīng)該在不到兩分鐘時(shí)間內(nèi)就將舊系統(tǒng)轉(zhuǎn)換到新的電腦系統(tǒng),但這涉及平行安裝兩個(gè)獨(dú)立控制服務(wù)臺(tái)進(jìn)行暫時(shí)控制。 </p><p&g

4、t;  工業(yè)解決方案和服務(wù)的現(xiàn)代化開始在2002年8月規(guī)劃。但一項(xiàng)重大挑戰(zhàn)是,實(shí)現(xiàn)現(xiàn)代化意味著幾個(gè)自動(dòng)化系統(tǒng)應(yīng)具有綜合的控制中心,而且新的自動(dòng)化技術(shù)的控制系統(tǒng)設(shè)計(jì)用于快速控制回路。,并且所有設(shè)備都要專為軋機(jī)環(huán)境而設(shè)計(jì)。</p><p>  EGC軟件包用于機(jī)電間隙控制,電動(dòng)機(jī)械的轉(zhuǎn)動(dòng)可以被單獨(dú)進(jìn)行位置控制或同步運(yùn)動(dòng)關(guān)閉離合器。為了提高實(shí)際位置采用螺桿式驅(qū)動(dòng)器,新的位置傳感器已經(jīng)安裝,連接到自動(dòng)化系統(tǒng)并通過系統(tǒng)總線

5、壓。</p><p>  厚度自動(dòng)控制( AGC ) ,利用超級(jí)AGC系統(tǒng)實(shí)行前饋補(bǔ)償,使計(jì)算好的厚度誤差在鑒定前通過檢測(cè)。軋機(jī)張力標(biāo)定可由操作員通過新的HMI系統(tǒng)和在半自動(dòng)模式下的運(yùn)行,讓運(yùn)動(dòng)發(fā)起的操作機(jī)構(gòu)和部位增損的價(jià)值轉(zhuǎn)移到優(yōu)化過程系統(tǒng),如軋機(jī)剛度計(jì)算。事實(shí)上,由于不同負(fù)荷條件下,壓力分布在軋制時(shí)受到軋件材料的寬度的影響,因此顯示如圖1,壓力分布應(yīng)該根據(jù)拉伸曲線作相應(yīng)的調(diào)整。</p><

6、p>  如圖1 .軋輥撓度的繪制曲線</p><p>  Trushape軋制是去年通過的規(guī)模和廣泛的變厚度剖面應(yīng)用于材料壁板序列。厚度曲線的計(jì)算方法是,通過優(yōu)化系統(tǒng)的進(jìn)程,并轉(zhuǎn)交控制系統(tǒng)作為一個(gè)多曲面。實(shí)際長度通過導(dǎo)向裝置來調(diào)節(jié),并且理論和實(shí)際計(jì)算長度之間的偏差,要使其適應(yīng)厚度曲線。每個(gè)支點(diǎn)的多邊形曲線,用來驗(yàn)證一套數(shù)據(jù)屬于合格數(shù)據(jù)的合理性。通過向板的位置,額外的厚度值被送到軋機(jī)機(jī)座上的AGC控制,但其中

7、需要途經(jīng)一個(gè)快速模擬信號(hào) 。 </p><p>  設(shè)置點(diǎn)的工作輥彎輥系統(tǒng)和穩(wěn)定的的軋制力波動(dòng),是根據(jù)過程計(jì)算機(jī),并轉(zhuǎn)交到了基礎(chǔ)自動(dòng)化系統(tǒng)計(jì)算出參考值。對(duì)于所有四個(gè)彎曲缸這些參考值將傳送給工作輥彎輥控制系統(tǒng)。</p><p>  液動(dòng)的側(cè)面導(dǎo)板,在前面和后面的機(jī)座,已分別配備新的位置傳感器相連,新的自動(dòng)化系統(tǒng)通過PROFIBUS DP。但在薄板軋制中,尤其重要的是要設(shè)計(jì)出一種優(yōu)化軋制和扭轉(zhuǎn)

8、序列以免浪費(fèi)時(shí)間和試件的溫度,并促進(jìn)重復(fù)性生產(chǎn)。試件的中心設(shè)定被自動(dòng)的設(shè)定為軋制序列的一部分,因此兩邊導(dǎo)向杠桿,是為了控制和監(jiān)督對(duì)稱運(yùn)動(dòng)。 </p><p>  為Trushape軋制和正常運(yùn)轉(zhuǎn)的超級(jí)AGC,準(zhǔn)確的材料跟蹤是必需的。幾個(gè)傳感器用于同步計(jì)算材料的位置。為長度計(jì)算,新的增量編碼器的主要驅(qū)動(dòng)器已安裝完畢。 </p><p>  在熱軋制道次之間等待間隔是必要的,在某些情況下為使第

9、二個(gè)或第三塊被同時(shí)地軋制,自動(dòng)化系統(tǒng)可以跟蹤不同的插入位置。這些控制自動(dòng)化系統(tǒng),用來協(xié)調(diào)軋制順序,確定哪些材料必須遷離或延遲軋制,并決定哪種材料將繼續(xù)在軋機(jī)上被軋制。由于中間介質(zhì)和終軋溫度在技術(shù)要求上非常重要,因此需要協(xié)調(diào)軋制制度,使其達(dá)到最佳化。為減少間隔時(shí)間,在熱軋軋制時(shí),中間冷卻區(qū)和快速冷卻區(qū)應(yīng)該設(shè)置妥當(dāng)。根據(jù)這個(gè)溫度要求,就必須把冷卻水用到板材上。將計(jì)算出的必要參數(shù)的2級(jí)系統(tǒng),轉(zhuǎn)交到過程自動(dòng)化系統(tǒng)。許多不同的冷卻時(shí)刻表必須予以考

10、慮各種材料的收縮范圍和制品的工藝流程?,F(xiàn)有儀器可測(cè)量中心線厚度和溫度變化圖,交叉寬度已經(jīng)完全集成在新的自動(dòng)化系統(tǒng)。</p><p>  兩種模式的裝置操作是可以適用的。在人工模式下的所有動(dòng)作和速度,是指由操作者決定; 此模式也用于換輥,校準(zhǔn)和維修。正規(guī)的運(yùn)作模式,是指在自動(dòng)模式下完成軋制順序和跟蹤的自動(dòng)控制。唯一的人工干預(yù)需要的是倒置試件,因?yàn)槿狈缀挝恢帽O(jiān)測(cè)設(shè)備因此這是必要的。</p><p

11、>  為了允許并聯(lián)運(yùn)行設(shè)備,在轉(zhuǎn)換期間,一種新型主操作臺(tái)的軋機(jī)被預(yù)先安裝在一提升控制臺(tái)后面,經(jīng)過熱試驗(yàn),舊工作臺(tái)被拆除,而新的操作臺(tái)轉(zhuǎn)到終點(diǎn)位置。</p><p>  控制系統(tǒng)的溝通需要利用光纖電纜外面的電器室建立一個(gè)新的廠內(nèi)網(wǎng)絡(luò)。該可視化系統(tǒng)的程序已被重新設(shè)計(jì),而余下的自動(dòng)化系統(tǒng)為了操作者的方便已被納入。強(qiáng)大的快速巡檢功能PDA系統(tǒng)已安裝,連接通過光導(dǎo)纖維的控制系統(tǒng)特性自動(dòng)巡檢程序已經(jīng)實(shí)施,并通過校正和評(píng)

12、價(jià)非標(biāo)準(zhǔn)事件。</p><p>  新的第2級(jí)過程優(yōu)化系統(tǒng)包括材料跟蹤,第3級(jí)接口接收和發(fā)送數(shù)據(jù)的能量生產(chǎn)報(bào)告中,接口的加熱爐和加速冷卻過程模型以及過程模型軋機(jī)功能說明如下。</p><p>  奧鋼聯(lián)(VAI.)鋼板生產(chǎn)和工藝技術(shù)訣竅結(jié)合了奧鋼聯(lián)鋼板廣泛的生產(chǎn)和加工的知識(shí)和經(jīng)驗(yàn)。 奧鋼聯(lián),其中包括自1974年一直從事中厚板軋機(jī)生產(chǎn)的前克萊西姆公司和戴維。在現(xiàn)行制度下,林茨獨(dú)立研制的奧鋼聯(lián)

13、于1999年啟動(dòng)??傊?,在鋼板世界各地的生產(chǎn)者中,奧鋼聯(lián)生產(chǎn)占了了近40個(gè)裝置。</p><p>  VAI鋼板生產(chǎn)是一個(gè)實(shí)時(shí)的數(shù)學(xué)模型,目的是為了設(shè)計(jì)優(yōu)化軋制過程中的可逆軋機(jī)。其主要職責(zé)是確定最優(yōu)軋制的生產(chǎn)率和產(chǎn)品質(zhì)量,考慮到軋機(jī)的物理限制和軋制工藝,并計(jì)算每個(gè)軋制道次的予設(shè)定程序 (輥縫,力量,速度,彎曲等) 。 </p><p>  計(jì)算板型設(shè)計(jì)要求有初步的產(chǎn)品特性(大小,溫度和材料

14、特性) ,最終性能和設(shè)備參數(shù)尺寸。基本物理模型是用來在軋制過程中,預(yù)測(cè)產(chǎn)品和軋機(jī)的品質(zhì)。一個(gè)先進(jìn)的軋機(jī)和最佳化戰(zhàn)略決定了軋制制度,為了滿足企業(yè)的生產(chǎn)力和產(chǎn)品質(zhì)量標(biāo)準(zhǔn)。最后,自動(dòng)校正是應(yīng)用在軋制過程中,在軋制期間由傳感器將測(cè)量到的尺寸傳輸?shù)娇刂葡到y(tǒng)來實(shí)現(xiàn)寬度自動(dòng)控制。</p><p>  與VAI.Plate不同的顯著特點(diǎn)有:在軋制時(shí),每一次的操作和周期性的延誤的重新計(jì)算,都可對(duì)程序進(jìn)行修改,考慮到軋制過程中的偏差

15、,壓力模型的自適應(yīng)和實(shí)際的板坯軋制溫度,最優(yōu)的軋制程序不能被確定,只能在每次軋制中制定出??焖賰?yōu)化技術(shù)可實(shí)現(xiàn)在完全實(shí)時(shí)的基礎(chǔ)上重新設(shè)定程序,因?yàn)榘逍问侵泻癜宓闹匾|(zhì)量指標(biāo),所以要采取具體的優(yōu)化方法來保證平坦度如圖2所示。另外,軋機(jī)的限制(最大沖擊力或力矩)和其他工藝因素也必須考慮在優(yōu)化設(shè)計(jì)內(nèi)。</p><p>  圖2.軋制力F和相對(duì)輪廓P分別越過出口厚度 </p><p>  為進(jìn)一步提

16、高產(chǎn)量,除了要有良好的厚度和寬度精度,板形(平坦度)也是生產(chǎn)過程中一個(gè)關(guān)鍵因素,特別是普通鋼板和厚板。為了控制軋制時(shí)的板形,在最后一次軋制時(shí),可按雙楔縱剖面軋制。簡單的計(jì)算楔形輪廓的高度和長度的方法是利用板寬度和板坯寬度比例。另一種辦法是采用統(tǒng)計(jì)方法來確定一個(gè)線性回歸公式,楔高度取決于板坯尺寸,通過數(shù)字和其他參數(shù)。VAI.Plate,在每次通過時(shí)計(jì)算外部形狀的演變,中間考慮到輥縫形狀(交叉輪廓)及橫向剖面的板塊和使用垂直邊的效果。數(shù)學(xué)優(yōu)

17、化方法是用來尋找最佳的參數(shù)設(shè)定立場(chǎng)限值( AGC )方式所計(jì)算,它最后形成的最偏離預(yù)期(大多是長方形)形狀。所以,縱軋輪廓在某些情況下會(huì)顯示出更復(fù)雜的形狀,而不是標(biāo)準(zhǔn)的雙楔曲線。</p><p>  一個(gè)實(shí)時(shí)的,完全三維計(jì)算熱凸度和磨損的確切輥形狀為軋輥?zhàn)冃文P吞峁┝司_的輸入,確保每道工序的精軋機(jī)張力和輥縫剖面計(jì)算準(zhǔn)確。實(shí)際上,在線算出全部軋輥?zhàn)冃危徊捎煤喕?,以減少計(jì)算時(shí)間,提供準(zhǔn)確詳細(xì)的三維有限元模型并改善

18、輪候時(shí)間及可實(shí)現(xiàn)軋制速度優(yōu)化。</p><p>  以上就是對(duì)厚板軋機(jī)自動(dòng)控制系統(tǒng)的一些簡單介紹。</p><p>  Plate mill automation</p><p>  The restart of TKS Plate Mill, Duisburg</p><p>  Jochen Bobbert1, Thomas Kraxbe

19、rger, Karl Scho rkhuber and Dietmar Auzinger</p><p>  The recent upgrading by VAI of automation equipment at the 3.9 m plate mill of ThyssenKrupp Stahl (TKS) in Duisburg-Su¨d, Germany involved the insta

20、llation of new equipment during regular maintenance shut-downs and caused no additional loss of production. To maintain full production capabilities, a switch-over unit was used to provide a seamless transition to the ne

21、w automation system. </p><p>  In 1978, a new rolling mill stand with a new main drive entered operation at the Heavy Plate Mill of Thyssen StahlAG in Duisburg Hu?ttenheim. With a rolling mill stand weight o

22、f 360 t and a backup roll diameter of 2100 mm at a width of only 3.7 m, the stand was extremely stiff and was also one of the first heavy plate stands in Europe to be equipped with hydraulic thickness control and a proce

23、ss computer,enabling tighter tolerances. However,the increasing implementation of laser welding in plate</p><p>  The last stage of an extensive modernisation program, begun in 1999,which included new contro

24、l systems for the reheating furnaces,modernisation of the stand hydraulics,etc., was the modernisation of the rolling process computer. This included the ‘basic automation’ (level 1) – i.e. The co-ordination of the rolle

25、r tables and side guides, the electromechanical and hydraulic adjustment system, the main drive, the work roll bending, the intermediate cooling, the intensive cooling system for the fina</p><p>  To make th

26、e transition to the new computer system as smooth as possible, a complex switch-over system was installed which allowed transfer from the old to the new computer and vice versa in less than two minutes. This involved the

27、 parallel installation of two independent control desks in the temporarily cramped control pulpit.</p><p>  VOEST-ALPINE Industrieanlagenba(VAI)Industrial Solutions and Services –began planning the modernisa

28、tion in August 2002. A major challenge wasthat past modernisations meant several automation systems had to beintegrated to act as one production unit.</p><p>  The ‘heart’ of the new automation is the techno

29、logical control systemdesigned for fast control loops. All equipment is designed for the millenvironment.</p><p>  The EGC SW package is used for electro mechanical gap control. The electromechanical screws

30、can be controlled individually in position control or in synchronous movement with closed clutch. To enhance the actual position reading of the screw-down drives, new position transducers have been installed,connected to

31、 the automation system via Profibus DP.</p><p>  The automatic gauge control (AGC) uses Super AGC, which implements feed-forward compensation of precalculated thickness errors identified during the preceding

32、 pass.</p><p>  The mill stretch calibration can be selected by the operator via the new HMI system and runs in semiautomatic mode, whereby movements are initiated by the operator and all measured force and

33、position values aretransferred to the process optimisation system, where the mill modulus is calculated. Due to the fact that different load conditions prevail since the pressure distribution during rolling is restricted

34、 to the width of the rolling stock, the stretch curve has to be adapted accordingly, as s</p><p>  1. Adaption of stretch curve for roll stack deflection</p><p>  During TruShape rolling, which

35、is the last pass of the sizing and broadsiding sequence, a variable thickness profile is applied to the material. The thickness curve is calculated by the process optimisation system and forwarded to the control system a

36、s a polygon curve.During the previous pass, the actual length is measured by the tracking and the deviation between the actual and the calculated length is taken to adaptthe thickness curve. For each supporting point of

37、the polygon curve, aset of da</p><p>  The set-point for the work rollbending system and the sensitivitiesfor roll force fluctuations are calculated by the process computer and forwarded to the basic automat

38、ion system which calculates referencevalues for all four bending cylinders;these reference values are transmitted to the work roll bending control system.</p><p>  The hydraulically operated side guides, in

39、front and behind the mill stand respectively, have been equipped with new position transducers,</p><p>  connected to the new automation system via Profibus DP. For thin gauge</p><p>  rolling i

40、n particular it is important to design an optimised rolling and reversing sequence, so as not to lose time and therefore temperature of the piece, and to promote reproducible production. The centring of the piece is done

41、 automatically as part of the rolling sequence, whereby both side guide levers are controlled and supervised forsymmetrical movement.</p><p>  For TruShape rolling and for properfunctioning of the Super AGC,

42、 accurate material tracking is mandatory. Several sensors are used to synchronise the calculated material position. For the length calculation, new incremental encoders for the main drives have been installed.</p>

43、<p>  In thermo-mechanical rolling waiting intervals between passes arenecessary in certain instances. To enable a second or a third piece to be rolled simultaneously, the automation system can track the position o

44、f the different pieces. In those cases the coordination function organises the rolling sequence, determining which material must be moved from and to the delay tables and decides whichmaterial will continue rolling at th

45、e rolling mill. Since the intermediate and finishing temperatures for th</p><p>  To reduce the waiting time during thermo-mechanical rolling,intermediate cooling areas and fast cooling areas are installed.

46、According to the target temperature, water may be applied to the plate, the necessary parameters being calculated by the level 2 system and forwarded to the process automation system. Many different cooling schedules mus

47、t be considered given the range of materialsand products processed.</p><p>  The existing instrumentation for measurement of centreline thickness and temperature profile across the width has been completely

48、integrated in the new automation system. </p><p>  Two modes of plant operation are possible. In manual mode all movements and speed references are initiated by the operator; this mode is also used for roll

49、change, calibration and light maintenance. The regular mode of operation for production is automatic mode where the complete rolling sequence and tracking is controlled automatically. The only manual intervention require

50、d is the turning of the piece, which is required because of the lack of geometrical position monitoring equipment.</p><p>  To allow parallel operation of the plant during the switchover period, a new main c

51、ontrol desk for the mill stand area was pre-installed in an elevated position behind the existing desk; after hot testing, the old desk was dismantled and the new control desk shifted to the final position.</p>&l

52、t;p>  For communication between the control systems a new plant networkwas established, making use of fibre optical cables outside the electrical rooms. The visualisation system has been redesigned for the entire proc

53、ess and the remaining automation systems have been incorporated for operators’convenience. For fast data logging functions a powerful PDA system has been installed, which is connected via fibre optics to the control syst

54、ems.Different automatic data logging routines have been implemented t</p><p>  The new level 2 process optimisation system comprises material tracking,interfaces to level 3 for receiving PDI data and sending

55、 production reports,interfaces to the reheat furnace and accelerated cooling process models as well as to gauges, and the process model and mill pacing functions described below.</p><p>  VAI. Plate plus int

56、egrates extensive production and process know-how and VAI.plate plus integrates extensive production and process know-how and experience. VAI, including the former Clecim and Davy, has been involved in plate mills since

57、1974. The current system, developed independently by VAI-Linz, was launched in 1999. In all,VAI has made nearly 40 installations at plate producers throughout the world.</p><p>  VAI.plateplus is a real-time

58、 mathematical model designed to optimise the rolling process in a reversing plate mill. Its major role is to determine an optimal rolling schedule in terms of productivity and product quality, taking into account the mil

59、l physical constraints and rolling practices, and to calculate the presets for each pass (roll gap, force, speed,bending, etc.).</p><p>  Calculating a pass schedule requires the initial product properties (

60、dimensions, temperature and material properties), the final properties and plant parameters (dimensions, rolls and constraints). Basic physical models are used to predict the behaviour of both product (temperature, flow

61、stress,rolling force and torque, shape and dimensions) and rolling mill (roll thermal crown and wear, mill stretch, roll gap shape) during the rolling process. A sophisticated rolling and optimisation strategy d</p>

62、;<p>  The particular features distinguishing VAI.Plate plus include:</p><p>  Recalculation during each pass and cyclically during delays makes it possible to revise a schedule during the rolling ope

63、ration, taking into account deviations in the process and benefiting from pass-to-passadaptation of the flow stress model and the actual plate temperature – the optimal schedule is never definitive and can be modified at

64、 each pass N fast optimisation techniques make it possible to recalculate the schedule fully on a real time basis, to make the presets available for the next p</p><p>  2 .Flatness diagram indicating roll fo

65、rce F and relative profile p for individualpasses over pass exit thickness</p><p>  Besides excellent thickness and width performance, outer shape (plan view) is a key factor for further improvement of yield

66、, i.e. the rati between customer plate mass and slab mass. To influence the shape that develops during rolling, a double-wedge longitudinal profile can be rolled during the last passes before the two standard 90u turns o

67、f the plate. Simple solutions calculate the height and length of this wedge profile, principally using the ratio between plate width and slab width.</p><p>  A further approach applies statistical methods to

68、 determine a linear regression formula for wedge height depending on dimensions, pass numbers, and other parameters.VAI.TruShapeplus calculates the evolution of the outer shape during each pass, taking into account roll

69、gap shape (cross-profile), transverse profile of the plate and the effect of using a vertical edger stand. A mathematical optimisation method is used to find an optimal parameter set within stand limits (AGC) for which t

70、he calculat</p><p>  A real time, fully three-dimensional calculation of the thermal crown and wear for the precise roll shape provides a precise input for the roll stack deformation model, ensuring precise

71、mill stretch and roll gapprofile calculation for each pass.VAI.rsd3D calculates the full rollstack deformation online without using simplifications to reducecomputing time, in effect offering the accuracy of a detailed 3

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