建模與優(yōu)化為20 - H的冷連軋課程畢業(yè)設(shè)計(jì)外文文獻(xiàn)翻譯@中英文翻譯@外文翻譯

附錄 -外文翻譯 Modeling and optimization for a 20-h cold rolling mill QUALITY and its reproducibility are dominant criteria for cold rolled products.In particular,high strip surface quality can be achieved with special mill arrangements such as the 20-h mill.This type of mill uses small work rolls in contact with the strip,that are kept in place with a variety of intermediate and backup rolls.The use of different actuators which,in part,only act indirectly to affect the roll bite geometry,makes the presetting of the mill with regard to strip thickness and flatness a complex task. This article describes a model the objective of which is optimizing the entire rolling process in a 20-h mill.Results obtained from several on-line applications are discussed. A closed sendzimirmill arrangement,shown in Fig.1,illustrates the main actuators that affect roll bite geometry with regard to strip thickness and glatness.Side eccentrics located at the backup rolls are used to adjust the overall position of the corresponding roll axis over a wide range which,indirectly,adjusts the roll gap geometry with regard to the millpassline and strip thickness.Side eccentrics may be mechanically or electrically coupled.Crown eccentrics are available at several locations over the barrel length.Those,typically on upper backup rolls,are capable of providing special roll gap contours.They match the gap to the profile of the strip entering the mill.Crown eccentrics are the major actuators for achieving strip flatness.Shiftable,first intermediate rolls are also shape actuators;they mainly serve for modifications in the strip edge area using a tapered roll profile. Measurement of mill geometry is available only indirectly through the rotation of the side and crown eccentrics and through the position of the first intermediate rolls. Consideration of mill spring and elastic deformation effects in the stack leads to the roll gap geometry.Accounting for mill spring and elastic deformation requires knowledge of the roll separating force which,in a closed 20-h mill,is measured indirectly through the adjustment pressure needed for the main side eccentrics.Apart from hysteresis effects,the effects of the variable geometry make this indirect measurement critical. Besides roll gap geometry,the task of presetting the mill also includes the design of pass schedules tailored to meet requirements of a product and the current mill condition.While optimal utilization of the mill is a major objective,the pass schedule must achieve the required produce quality.Generation of pass schedules to cover the statistical average and storing them in databases related to steel grade,surface and coil geometry is state of the art technology,In particular,mill parameters such as roll geometry or the thermal condition of the work rolls require dynamic correction of the pass schedules to obtain a reproducible final product.The same applies to variations in the material characteristics of the coils rolled. Because of the complexity of 20-hmills,achieving reproducibility of the final product quality and the optimum use of available mill resources to increase productivity represents an extremely difficult task.This task can be accomplished with a comprehensive model approach that takes all relevant mill and process parameters into account. To optimize the porcess,various mathematical models are needed to describe the elastic stand behavior and the elastic/plastic characteristics of the material to the rolled because neither direct geometrical information nor accurate roll force measurements exist. 1、 Force,torque and power The roll force,roll torque and drive power necessary to form the material are some of the most important items of process information.While power requirements affect the design of a pass schedule for optimal use of the available mill resources,roll force is mandatory for presetting the geometrical actuators.Both force and torque,on the other hand,need to be known for mill presetting so that mechanical or practical limits are not exceeded. The approach selected to describe the effects in the roll gap with regard to power,torque and force,is based on a strip fiber model using the basic theory developed by Karmanand Siebel.The roll gap model provides both vertical and tangential stress components acting on the work roll.The roll separating force results from the integration of the vertical pressure components.Torque and drive power are derived from the tangential stress. The roll gap model simultaneously provides accurate information about the vertical and tangential stress components acting on the roll and,thus,the drive power and roll force. The ability to evaluate the rolling process,based on accurate calculation of the roll separating force and main drive power,enhances,in particular,the material yield stress evaluation.This is beneficial since the roll force measurement is affected,to a large extent,by measurement hysteresis present in a closed 20-h mill. 2、 Material yield stress adaption Material yield stress adaption is required in any case where there is the need to roll a wide range of steel grades.Also,the demand for self-learning model algorithms forces the use of adaptive methods with regard to the yield stress. The yield stress of the material is initially evaluated in off-line tests using torsion bar samples.While off-line tests provide good initial information,each process and product has its own personality.This may result from the annealing practices or variations in the chemical composition of the steel grades. The yield stress adaption is broken down into a short-term adaption to rapidly adjust the yield stress curve,and a long-term adaption,where complex relationships between strain,strain rate and temperature are evaluated and represented. Statistical yield stress information is available by grade and also on an individ ual coil basis if needed,which improves quality assurance. 3、 Friction representation Besides obtaining a representation of the material yield stress,it isalso mandatory to describe the friction in the roll gap.In a variety of applications,the friction coefficient is adjusted so that during long-term analysis the most appropriate friction coefficient;ie,the coefficient that provides the best match between calculation and measurement,is applied. Another approach is to carry out rolling tests and analyze the results.While rolling tests affect production, the analysis method is time-consuming and may often have the disadvantage that not all relevant factors affecting friction are adequately considered.The approach selected in the current study is based on an artificial neural network. The entry layer of the neural network receives all relevant information as it has been gathered and may affect friction.This information is processed through the multilayer perceptron feed forward network in an off-line investigation using the back propagation method for training that,finally,leads to the friction coefficient.With a representative work,even physical relationships between the friction coefficient and process information can be evaluated. The results derived from the neural network have been used as the basis for an analytical model,which was implemented on-line. The accuracy of the representation has been evaluated in several on-line rolling tests in industrial facilities.Since mill speed is one of the main variables affecting friction,one pass was made during the commissioning phase of the model with different mill speeds.Both the measured and calculated roll force were recorded. Apart from the friction coefficient,both the temperature of the strip approaching the roll bite and the strain varied in the test. 4、 Elastic mill stand behavior In addition to roll force,power and torque,the elastic behavior of the mill stand must also be described to allow propagation from the measured eccentric adjustments to the roll bite contour,which is the target for further optimization steps. One requirement in the elastic mill stand model was its ability to cover a variety of different mill configurations,roll profiles and roll materials.These variables were also specified with respect to each individual roll in the stack to cover situations where unusual roll combinations are selected and to allow the model to be used during design phases. To provide maximum flexibility,the description of the elastic mill stand behavior is based on a numerical solution approach for the roll stack.The different effects,such as flattening between the rolls,flattening between the strip and the work rolls,and deflection of the several rolls,are derived from multiple iterations. The elastic mill stand model for the 20-h cold rolling mill can,generally,be divided into two parts.The initial phase involves a rapid determination of the load share in the second phase.The initial load share derived is then taken,in the second phase,as basis for the iterative determination of the interaction between load distribution,flattening and deflection. The deflection of each roll is derived from the load distribution determined in each iteration step.The geometrical differences between neighboring rolls are interpreted as flattening of the rolls for which a certain load distribution must be present.This leads to a new load along the contact area of the various rolls.This new load distribution leads,again,to a new deflection. The total effect of elastic deformation between the rolls produces a new load at the saddle segments of the backup rolls.Thus,the mill spring appears to be different,and a new iteration needs to be performed.The iteration is carried out until a solution has been reached,where the entire load,the deflection and flattening match. 5、 Summary The accuracy of force measurement in a closed sendzimir mill is inadequate for high-precision process control.To solve this problem,special model for determination of roll force and roll torque has been developed.The tangential and vertical stress components acting on the work rolls are described to permit the calculation for yield stress adaptions based on the power consumption of the main drive. A model has been developed that describes the elastic mill stand behavior and considers the interaction of roll deflection with load distribution and roll flattening.The model represents a multiple iterative solution approach. 建模與優(yōu)化為 20 - H的冷連軋 質(zhì)量和可重復(fù)性是其主導(dǎo)的標(biāo)準(zhǔn)，冷軋 products.in ，特別是高帶鋼表面質(zhì)量能達(dá)到與軋機(jī)特別安排，如 20小時(shí) mill.this類型的用途，小軋機(jī)工 作輥在接觸帶，即是存放在地方與不同的中間和備份 rolls.the使用不同的驅(qū)動器，在部分中，只有法，間接影響到軋輥咬幾何，使預(yù)設(shè)的軋機(jī)方面帶的厚度和平整度是一項(xiàng)復(fù)雜的任務(wù)。 本文介紹了模型的目的是優(yōu)化整個(gè)軋制過程在 20小時(shí) mill.results獲得來自數(shù)個(gè)上線應(yīng)用的討論。 一個(gè)封閉的 sendzimirmill的安排，顯示在圖 1 ，說明的主要?jiǎng)佑绊戃堓佉缀畏矫鎺У暮穸群?glatness.side eccentrics位于備份卷是用來調(diào)節(jié)整體的立場，相應(yīng)的輥軸較廣泛范圍內(nèi)，間接，調(diào)整輥縫幾何方 面向 millpassline帶thickness.side eccentrics可能是機(jī)械或電動 coupled.crown eccentrics可在幾個(gè)地點(diǎn)超過每桶 length.those ，通常是在上備份卷，有能力提供特別輥縫 contours.they匹配的差距概況帶進(jìn)入 mill.crown eccentrics是主要的致動器實(shí)現(xiàn)帶 flatness.shiftable ，第一中間輥也形成動，他們主要是為修改，在帶邊緣區(qū)使用錐形輥。 測量軋機(jī)幾何只可間接透過旋轉(zhuǎn)的一側(cè)和官方 eccentrics并通過的立場，第一中間輥。 審議軋機(jī)春季和彈性變形的影響，在堆棧，導(dǎo)致登記冊上的差距geometry.accounting軋機(jī)春季和彈性變形，需要知識的軋輥分離力，在一個(gè)封閉的 20 - H的軋機(jī)，是衡量間接透過調(diào)整的壓力，需要為主要方 eccentrics.apart從滯后效應(yīng)，影響的可變幾何使這個(gè)間接測量的關(guān)鍵。 此外輥縫幾何，任務(wù)預(yù)軋機(jī)，還包括設(shè)計(jì)通過附表定制，以滿足要求的產(chǎn)品，以及目前軋機(jī) condition.while最佳利用軋機(jī)是一個(gè)重大的目標(biāo)，通過附表必須達(dá)到規(guī)定的生產(chǎn) quality.generation的通行證附表涵蓋統(tǒng)計(jì)平均，并把它們保存在數(shù)據(jù)庫相關(guān)的鋼級，地表水和線圈幾何是國家的最先進(jìn)的技術(shù)，特別是軋機(jī)參數(shù)，如軋輥幾何或熱條件下的工作輥要求動態(tài)修正的通過附表取得重現(xiàn)最后產(chǎn)品的同樣適用于不同的材料特性的線圈推出。 因?yàn)閺?fù)雜 20 - hmills ，實(shí)現(xiàn)重復(fù)性的最終產(chǎn)品的質(zhì)量和最佳利用現(xiàn)有軋機(jī)資源，以增加生產(chǎn)力，代表了一個(gè)極端困難的 task.this的任務(wù)可以完成一個(gè)全面的模型方法，考慮所有相關(guān)的磨和過程參數(shù)在內(nèi)。 優(yōu)化 porcess ，各種數(shù)學(xué)模型需要來形容 彈性的立場，行為和彈性 /塑料的特性的材料軋制，因?yàn)闆]有直接的幾何信息，也沒有準(zhǔn)確的軋輥力的測量存在。 1.武力，扭矩和功率 軋輥武力，滾轉(zhuǎn)力矩和驅(qū)動力要形成的物質(zhì)是一些最重要的項(xiàng)目進(jìn)程information.while電力需求影響的設(shè)計(jì)，合格的時(shí)間表，優(yōu)化利用現(xiàn)有的資源，軋機(jī)，軋輥的力量是強(qiáng)制性的為預(yù)設(shè)幾何 actuators.both武力和扭矩，另一方面，需要被稱為軋機(jī)預(yù)設(shè)，使機(jī)械或?qū)嶋H限制是不得超過。 選定來形容的影響，在輥縫方面的權(quán)力，扭矩和力量，是基于一個(gè)帶纖維模型使用的基本理論研 制的 karmanand siebel.the輥縫模型提供縱向和切向應(yīng)力分量作用于工作 roll.the軋輥分離力的結(jié)果，從一體化的垂直壓力components.torque和驅(qū)動力是來自切向應(yīng)力。 該輥縫模型，同時(shí)提供準(zhǔn)確的資料，有關(guān)垂直和切向應(yīng)力分量署理對軋輥，因此，驅(qū)動電源和軋輥的力量。 能力評價(jià)軋制工藝的基礎(chǔ)上，精確計(jì)算軋輥分離力和主要驅(qū)動力，增強(qiáng)了，特別是材料的屈服應(yīng)力 evaluation.this是有利的自輥測力受到影響，相當(dāng)大的程度上，由測量滯后，目前在一個(gè)封閉的 20 - H的軋機(jī)。 2.材料的屈服應(yīng)力適應(yīng)性 材料的屈服應(yīng)力適應(yīng)是需要在任何情況下，是有需要推出廣泛的鋼grades.also ，要求自學(xué)模型算法勢力利用自適應(yīng)方法方面的屈服應(yīng)力。 屈服應(yīng)力的材料是初步評估，在離線測試使用扭桿 samples.while脫線測試，提供了良好的初步資料，每個(gè)過程和產(chǎn)品都有自己的 personality.this可能會導(dǎo)致從退火的做法或變化的化學(xué)組成鋼職系。 屈服應(yīng)力適應(yīng)細(xì)分為短期的適應(yīng)迅速調(diào)整屈服應(yīng)力曲線，和長期的適應(yīng)，之間的復(fù)雜關(guān)系應(yīng)變，應(yīng)變速率和溫度的評價(jià)，并代表。統(tǒng)計(jì)屈服 應(yīng)力所得的資料，按職等和還就