板料矫直机设计【说明书+CAD+SOLIDWORKS】
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板料矫直机设计【说明书+CAD+SOLIDWORKS】
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说明书
CAD
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任务书(理工类)学生姓名： 专 业： 班 级： 学 号： 指导教师： 职 称： 完成时间： 毕业设计(论文)题目：板料矫直机设计题目来源教师科研课 题纵向课题（ ）题目类型理论研究（ ）注：请直接在所属项目括号内打“”横向课题（ ）应用研究（ ）教师自拟课题（）应用设计（）学生自拟课题（）其 他（）总体设计要求及技术要点：1、设计参数 矫直材料Q235，板厚H=515mm，最大板宽B=2000mm；矫直温度400600；矫直速度0.51.5m/s；矫直辊辊距280mm；辊径250mm；辊身长2350mm，5个上辊，4个下辊；支承辊辊径280mm、辊身长900mm、3个上辊、4个下辊；最大开度140mm； 2、设计要求 压下装置采用一台5.5kw、1455r/min的交流电机驱动；主电机一台、200kw、980r/min、交流。工作环境及技术条件：需使用PC机进行机械工程图的绘制、计算机辅助设计，学生可以充分利用系里的CAD/CAM实验室进行设计工作；设计有关的各种手册和资料和从学校图书馆接阅；另外可以充分利用学校的数字图书资源，查阅中、英文文献。工作内容及最终成果：1.查阅相关文献及中外文资料，撰写文献综述，撰写开题报告。2.撰写毕业设计（论文）说明书：（1）绘制矫直机总装配图（A0）一张。（2）绘制矫直机部装和零件图（打印部装图A1）二张。（3）绘制三维总装配图（A3）一张。（4）毕业设计报告一份。时间进度安排：1. 2016年11-12月，查阅资料，完成开题报告、文献综述、外文文献翻译。2. 2017年3月，开题报告审阅。3. 2017年4月，基本结构分析。4. 2017年5月，总体结构设计，绘制工程图。5. 2017年6月，整理最后资料，完成毕业设计论文，准备答辩。指导教师签字： 年 月 日教研室主任意见：教研室主任签字： 年 月 日设计 (论文)外 文 翻 译原 文 标 题AUTOMATING THE CONTROL OF MODERN Operated Melon Shelling Machine using Impact Technique of Manually and MotorizedOperated Melon Shelling Machine using Impact TechniqueEQUIPMENT FOR STRAIGHTEOperated Melon Shelling Machine using Impact TechniqueNING FLAT-ROLLED PRODUCT Technique译 文 标 题现代化矫直轧制薄品设备的自动化控制作者所在系别作者所在专业作者所在班级作 者 姓 名作 者 学 号指导教师姓名指导教师职称完 成 时 间教务处制译文标题现代化矫直轧制薄品设备的自动化控制原文标题AUTOMATING THE CONTROL OF MODERN EQUIPMENT FOR STRAIGHTENING FLAT-ROLLED PRODUCT作 者YN Belobrov,VG Smirnov,AI Titarenko,译 名百伦布若国 籍美国原文出处Mechanical Engineering Department, Faculty of Engineering and Technology University of Ilorin, P.M.B. 1515, Ilorin, Nigeria.Received 13 December 2008; Accepted 23 February 2009译文：谢韦尔钢铁公司在2003年8月成功完成了新引进的规格为28005000米尔的直线式钢板矫直机（平台相关模型）。机器的主要设计特点如下：l 每台机器配备液压紧固装置(用于改善机器的动力学性能和调整的准确性以及更可靠地保持恒定的间隙)l 每台机器都有能在液压缸的辅助下分别调节每根工作辊的机构(通过提供一种控制钢板的曲率变化的方法来实现拓宽矫直范围的目的)。l 每个工作辊具有它自己的调节驱动(去除主轴之间的刚性运动学制约）l 该系统平台相关模型的辊轴是封装在封闭箱（录音带）中的(便于维修,降低替换辊的成本)l 这个模型有一个系统,它可用于调整机器从九辊矫直方案转变为五辊矫直方案，过程辊间的距离增加了一倍(这是为了扩大机器对板厚度的可允许范围)。因此,新的矫直机是一个多功能、复杂的机器,其包括一个可由数字和模拟信号控制的宽范围、电驱动元件的液压组件。整个复杂的机构可以分为两个功能机体：主要的机体,包括直接参与矫直操作的机构(其夹紧装置能独立适应轧辊,调整组件以适应不同的矫直要求,可移动支线和主传动装置的上辊) ；辅助装置(包括盒式替代装置、主轴锁定机构、辊轴支架设备冷却系统)。虽然平台相关模型有大量的机制,运用现代液压和电气驱动，能够在平台相关模型和其运转机构上几乎完全的实现对主要和辅助机构的自动化控制操作。下面描述的是薄板矫直机的特点以及自动控制系统的最重要的机理，同时对操作机理也进行了探讨。薄板矫直机的液压紧固机构(HHMs)功能在于两大系统:调整系统；指定位置的维护系统。对控制系统和某些有效条件系统存在一定的要求。在液压紧固机构的调整系统、控制系统,必须做到以下几点：l 液压缸的同步运动保持，角偏转到规定的限量以内；l 为适应新板的尺寸的最大调整速度；l 保持高的定位精度的机制；该控制系统在维护系统操作时具有以下要求：l 使封闭箱的（录音带）附件保持稳定，同时保证给料机的上辊具有较高的准确性；l 当偏差出现时，最大限度地减少设备返还到约定坐标所需的时间(例如金属板由于被矫直时而显现出的弹力)。同步需求。根据谢韦尔钢铁集团3号金属板矫直机组得出的操作经验,调整机器时最不确定的因素是因为应用液压缸儿产生的不均匀力。这种非均匀性是由平台模型上大部分活动部件不对称分布所引起的（特别是主轴装配时的偏重效应）。伺服阀的“液压零点”与“电气零点”的相对位移也是一个因素。液压缸的体积越小后者越重要。因此，给料机上辊的HHM的零点漂移是最敏感的。也有其他因素的影响,同时性, 紧固机制的同步运行：l 液压缸上部分区域的摩擦力的差别源于成对零件的规模大小的组合差异，即使偏差非常的小；l “弹起”差异特征和液压供应渠道的惯性表征指标(由于液压缸的伺服阀不同长度管的入口)。因此,即使模型上没有配置机械地保持液压缸操作同步的装置, 伺服阀的相同振幅信号的传输的输入不可避免导致一个严重危害机器的速差。对降低及消除上述因素的影响,研制出一种对紧固机制进行电气同步的算法。包括四个紧固缸、四个平衡缸的封闭箱顶部的HHM,是为保证机器的灵活的调整设定所需尺寸的矫直差(按照板的厚度),并通过现有的准确性和遮蔽物上矫直力的符合缺乏来维持这个精度范围。液压系统的紧固机制设计是这样一种方式,只有一室的液压缸,是用来作为工作室。第二室总是与排泄通道相连。平衡力量被紧固气缸克服时封闭箱降低顶端的。只有在气缸平衡时封闭箱才提起。这样的布置可以消除精度范围在设备上的影响。顶部的HHM的辊的支线由两个液压缸组成。当辊被提升的同时，辊降低和油液输入杆腔，液柱塞腔被注入液油。控制原则。特有电路如图所示(图1),来控紧固机制的液压缸。伺服阀输入端的控制信号（Xctl）是由一个比例-积分(PI)控制器传递的(为了提高灵系统的敏度,我们选择了用瓣膜,以“零”触发)。输入信号（错误信号Xerr）发送到控制器的输入端后形成位置（Xcpt）和反馈信号的要点控制信号（Xf.b），后续信号是从所给液压缸的直线位移轨距（G）接收的。密封箱顶部的HHM的标定测量头组成了平衡液压缸(HCs)。气瓶是安装了这样一种方式,他们的动作可以被认为是等于位移相应圆柱棒、与津贴为某些系数。支线上辊的HHM的测量头组成了紧固气瓶。该控制器的不可分割的组成部分,仅在最后被激活时调整阶段和稳定规定的坐标。当位移超过一定阈值,PI控制器的功能是被一个比例(P)控制器的传递函数所代替的W(s)= k。因此,Xctl(t)= kXerr(t)。当有工作中的辊子有非常显著的差异时,这其中之间的关键控制点和反馈信号的区别(误差)从直线位测量达到足够大,这样值输出信号控制伺服阀的操作达到饱和区。在这种情况下,进一步位移、速度和同步动作的规定,这样当误差超过范围时气缸的同步移动变得不可能，这时Xctl大于饱和区的边值问题(Xsat)。通过减少k来解决特定的问题导致了在调整PSM时的速度损失和矫直机的操作中控制精度的降低。因此,为了保持控制信号到达饱和区当有大的位移、整个系统的设计，这样的输入端控制器并不是实际的所需值（Xrq),但增量(X)是巨大的，k X Xsat 这样的状况是令人满意的。液压缸的位置变化后，控制点的增加取决于X的大小，其与相对于圆柱的运动方向相应的有最大的滞后量有关。调整的关键控制点维持现状，直到所需要求和装置的实际位置之间的差异小于其增量：Xrq Xf.b X。然后控制器的输入适应其增值Xcpt，相当于调整要求：Xcpt= Xrq。调整如此完成。使用的原则是一步几乎对所有的理想重复的因素而言，增加控制点使人们有可能同步运动的汽缸和设置的关键控制点以高度的准确性。独特的调整机制工作辊。平板矫直机如此设计通过借助于V-belt驱动液压缸动作来实现每个工作辊可以移动垂直。通过操作与比例伺服阀的控制来提供液压缸的动力。线性位移测量器设置在每一个液压缸上获得辊的位置反馈信号。由于这些测量头实际上是传递着液压拉杆的位置信息而不是工作辊本身，在接下来的转换中来得到坐标：kred驱使齿轮d动比;Xf.b是通过直线位移传感器测量的柱杆位置。因此,位置反馈电路反应了各项工作辊的姿态控制。图1为电路图。控制信号产生采用PI控制器,它使得人们有可能达到了高度的调节系统的预测精度而不损失速度。独立驱动的辊子。这四种设计是基于使用独立驱动的交流电机，其分别采用了不同动力反馈的变频器。每一个单独的驱动提供了以下一种优于集中驱动:l 由于在组件的机制中存在着线性工作辊和速度板之间速度不同的这种可能性；l 如果一个乃至几个驱动器出现故障，这台机器可以继续操作，但在这种情况下,相应的矫直辊的驱动将会被停止；l 辊子的线性速度的可能性滚筒可单独按照矫独有的直板进给的实际速度；l 辊子的线速度按照实际板材的速度进行更正成为可能,其速度可以进行一个修正或者作为一个初步调整措施；l 这样的修正作为一个初步措施（在测量和理论计算的基础上)或在矫直机的实际操作中(在操作中获得的数据和采用变频调速器实现人工智能的基础上)。矫直机的主传动为的矫直机九个矫直辊与两个辅助辊。该驱动必须在操作中高度可靠,如果驱动不能正常工作甚至持续很短的一段时间，意味着轧机生产线的生产量可能会招致损失。驱动所必须满足的要求决定于机器整体的操作和设备的设计特点：l 板材被矫直就必须在矫直机的下辊、上辊和相邻输送辊之间创造一个刚性运动耦合关系的；l 板材应该承受到矫直机矫直操作中所导致的伸长塑性变形,伸长长度的不同增加是因为每个工作辊弯曲半径的分化；这种情况导致了当板材移动快到PSM的末端时速度的不均匀增加；l 必须使使用不同直径的工作辊成为可能(这是必须的,比如说,由于不均匀磨损)；l 负载辊应依照选择而分化矫直体系；l 反向矫直应当是可行的。l 根据上述因素以及实际操作的体系板材矫直机正在被研制在这里,下列要求建立电力驱动:l 广泛的范围内规定的速度,包括启动马达在荷载作用下；l 在逆向体系中的运行；l 一个刚性的特点 = (M)；l 在保持规定的速度中有高度的准确性；l 完全同步操作。 要求操作者显示想要的位置的底部(5 -或9辊子l矫直);调整顶部和底部的间距;为工作辊子的个别调整设定坐标,选择的矫直速度和方向;产生一个命令给机器开始调整到指定的机构。这机器是自动适应所选择的机构。调整完成后时,一个信号发送给控制面板显示的坐标的状态发生了变化,预示这些已经达到他们的滚筒规定的工作速度。在自动变量中、板式矫直机是为基础调整的数据发送通过数据网络从更高水平的系统。这些数据包括下列事项:l 被矫直板的厚度;l 钢的组别 (物质比例的信息);l Psm入口的温度;l PSM调整分几个阶段:l 初步调整基于钢板厚度及钢铁的种类,为冷轧钢板(t = 20C);l 基于安装在距psm50m的高温计获得的数据作进一步调整;l 基于安装在机器入口的高温计做最终调整;l 在自动变量控制辊输送毗邻机是转向了控制。系统的诗作为下一盘方法这台机器。在这种情况,该盘直到及其调整完成才能进入工作区域。如果有必要板通过机器没有矫直它,本机完全改变到运输的状态。在这种情况下,顶端的横木与黑盒将以规定的数量被提升并且辊子的速度被改变,以致于它的速度等于相邻辊输送线。磁带替换机制将被应用在辊子损坏的情况或有必要再研磨工作辊和后排辊,在这种情况下,操作者能控制辅助机制的运行:主轴锁定机制、滚动式推车、底部的机制,锁住底部录音带和车里的位置,推动车的液压缸。通过非接触传感器固定机器的位置。PSM控制系统。板式矫直机的控制要求一种功能强大的、高能力体系的开发,该体系可以提供需要的控制精度与快速的运转相结合。 该控制系统分为两个层次:基层,和一个上层。诊断系统作为一个独立的系统创建。第二个控制器对PSM的控制泵站进行控制。基层的控制系统采用一种西门子系列S7的可编程工业控制器,而上层和诊断系统建立在标准电脑的基础上。用于上层系统的计算机也作为PSM的控制面板。 不同要素的控制系统由两圈连接的PROFIBUS网络来连接，如图3所示。第一个循环的功能是作为控制器、上层计算机、诊断站以及pump-station控制器之间的通信连接。第二个循环把PSM控制器和系统的功能元素连接起来（即频率转换器，线性位移量具和远程输入输出模块）。基于以下准则，将控制系统的功能在基层和上层区分开来：基层承担涉及从传感器接收数据的机制安装、从自动过程控制系统板上获取即将矫直的信息、为执行机构产生和传输控制信号（执行器）的功能；上层承担控制要点的归档以及监控控制面板操作的功能。 以下特定功能是由基层的自动化系统来执行的：l 从上层系统获取指定的矫直参数（辊子转速，顶部横臂的坐标，辊子相对于横臂的坐标）；l 处理参数，给执行机构发送相应的控制信号； l 从安装在机制上的传感器获取信息来决定PSM是否正确安装以及是否为矫直机操作做 好准备。 l 从安装在机制上的反馈变送器获取信息来估算控制措施；l 分析传感器读数来决定数据的准确性； l 与PSM泵电池站（PBS）进行数据交换，并发射站的运行参数到到上一级以进行显示。 表1 平板矫直机的机器规格参数机器型号LPM 2800LPM 5000厚度，mm宽度，mm长度，mm板材最大屈服点，MPa矫直速度，m/sec矫直力，MN矫直后钢板残余曲率(在整个厚度范围),mm/m76015002700from 50008500.30.630.03.01010015004800from 800012500.20.650.03.0l 从上一级系统获得初始数据进行自动校正和数据传输以便进行适当的调整。上一级自动化系统的功能如下：l 在矫直管理系统中输入数据以便随后进行状态选择，并将信息录入数据库中；l 从数据库中手动选择矫直状态以选择相应板材（这个由操作者完成）；l 在从上一级系统中获得信息的基础上，从数据库中自动选择矫正状态；l 在矫正和盒子替换过程中进行手动控制机器表明机构定位的根据是传感器和限位开关的位置读数；l 表明一个金属板存在于PSM的工作区；l 表明金属板的温度是由高温计测量得到的；l 视觉代表矫直系统和机器调整；l 视觉代表机器结构和PBS的情况以用于诊断目的；l 远程输入输出模块ET200是用来为未校准的驱动装置供电。立柜中包括继电器和接口，因为这些驱动器距离控制者有相当长的一段距离。该模块的应用，使电缆长度的有效缩短成为可能。诊断系统。高浓度的电器及液压设备中包括类似PSM设备的一部分，这些设备与机器本身有一段距离，并且常常是难以到达的地方，这使之更难以为机器提供服务和寻找问题根源。为方便PSM的保养和维修时间的缩短，必须建立一个先进的诊断系统。该系统是基于安装在控制岗位的工业控制计算机。它诊断PSM各种机构，以及它的液压和电气设备的状态。该系统可用于评估的自动开关的条件下，电机的温度传感器，线性位移计，当地PROFIBUS网络终端，电流，速度和电机的旋转方向，以及其他设备和参数.诊断系统也可用于建立的PSM的操作协议。其文件包括即时的数据和错误的类型和发生故障的设备，机构的坐标，电机电流和速度，以及其他信息。为了使控制系统更可靠，诊断台的软件和硬件与控制系统的上一级相应的组件相对应。当电脑控制操作发生问题时，PSM的控制功能可以转移到诊断系统的计算机上面。结论，NKMZ曾与独立国家联合体（独联体）的创始伙伴合作，成功地引进了装有现代自动化控制系统的板矫正机。使用机器使人们有可能减少或者几乎完全消除成品板质量对机床操作人员技能的依赖。控制系统，连同其方便的用户界面，让即使没有受过专门培训的人迅速掌握机器的操作。高品质的产品的生产是在机器的运动机制保证下的确切结果，并且其位置精确度也由其得到保证，这得益于具有比例控制和特殊控制算法的精密设备。此外，该机配备了先进的诊断系统，它也记录关键参数。该系统可方便机器的许多复杂的零部件的维修和保养。原文：The company Severstal completed the successful introduction of new in-line plate-straightening machines (PSMs) on its 2800 and 5000 mills in August 2003 1, 2, 3. The main design features of the machines are as follows:l each machine is equipped with hydraulic hold-down mechanisms (to improve the dynamics and accuracy of the machine adjustments and more reliably maintain a constant gap); l the machines have mechanisms to individually adjust each work roller with the aid of hydraulic cylinders (this broadens the range of straightening regimes that can be realized by providing a measure of control over the change in the curvature of the plate);l each work roller is provided with its own adjustable drive (to eliminate rigid kinematic constraints between the spindles);l the system of rollers of the PSM is enclosed in cassettes (to facilitate repairs and reduce roller replacement costs);l the PSM has a system that can be used to adjust the machine from a nine-roller straightening scheme to a five-l roller scheme in which the distance between the rollers is doubled (this is done to widen the range of plate thick-nesses that the machine can accomodate).Thus, the new straightening machine is a sophisticated multi-function system of mechanisms that includes a wide range of hydraulically and electrically driven components controlled by digital and analog signals. The entire complex of PSM mechanisms can be divided into two functional groups: the main group, which includes the mechanisms that partici-pate directly in the straightening operation (the hold-down mechanisms, the mechanisms that individually adjust the rollers,the mechanisms that adjust the components for different straightening regimes, the mechanism that moves the top roller of the feeder, and the main drive); the auxiliary group (which includes the cassette replacement mechanism, the spindle-lock-ing mechanism, and the equipment that cools the system of rollers). Although the PSM has a large number of mechanisms,the use of modern hydraulic and electric drives has made it possible to almost completely automate the main and auxiliary operations performed on the PSM and the units that operate with it.Described below are the features and the automatic control systems for the most important mechanisms of the plate-straightening machine.The operating regimes of those mechanisms are also discussed.The hydraulic hold-down mechanisms (HHMs) of the sheet-straightening machine function in two main regimes:the adjustment regime;the regime in which the specified positions are maintained.There are certain requirements for the control system and certain efficiency criteria for each regime.In the adjustment regime, the control system for the hydraulic hold-down mechanisms must do the following:l synchronize the movements of the hydraulic cylinders and keep the angular deeflection within prescribed limits;l maximize speed in adjusting the machine for a new plate size;l maintain a high degree of accuracy in positioning the mechanisms; The control system has the following requirements when operating in the maintenance regime:l stabilize the coordinates of the top cassette and the top roller of the feeder with a high degree of accuracy;l minimize the time needed to return the equipment to the prescribed coordinates when deviations occur (such as due to the force exerted by a plate being straightened).Need for synchronization. Experience in operating the plate-straightening machine in plate shop No. 3 at Severstal has shown that the most problematic factor in adjusting the machine is the nonuniformity of the forces applied to the hydraulic cylinders. This nonuniformity is due to the asymmetric distribution of the masses of the moving parts of the PSM (in particular, the effect of the weight of the spindle assembly). Displacement of the “hydraulic zero point” relative to the “electrical zero point” in the servo valves is also a contributing factor.The latter reason is more significant, the smaller the volume of the hydraulic cylinder.Thus, the HHM of the top roller of the feeder is the most sensitive to drift of the zero point.There are also other factors that affect the dynamism,simultaneousness,and synchronism of the operation of the hold-down mechanisms:l differentiation of the frictional forces on parts of the hydraulic cylinders due to different combinations of deviations in the dimensions of the mated parts, despite the narrow tolerances;l differences in the “springing” characteristics and the indices characterizing the inertia of the hydraulic supply channels (due to differences in the lengths of the pipes leading from the servo valves to the hydraulic cylinders).Thus, since the PSM is not equipped with devices to mechanically synchronize the operation of the cylinders, the ransmission of signals of the same amplitude to the inputs of the servo valves inevitably results in a speed difference that can seriously damage the mechanisms.To minimize and eliminate the effects of the above-mentioned factors, we developed an algorithm for electrical synchronization of the hold-down mechanisms.The HHM of the top cassette, composed of four hold-down cylinders and four balancing cylinders, is designed to ensuremobile adjustment of the machine to set the required size of straightening gap (in accordance with the thickness of the plate) andmaintain that gap with a specified accuracy in the presence .and absence of a load on the housings from the straightening force.The hydraulic system of the hold-down mechanism is designed in such a way that only one chamber of the hydraulic cylinders is used as the working chamber.The second chamber is always connected to the discharge channel.The top cassette is lowered when the balancing forces are overcome by the hold-down cylinders.The cassette is raised only by the action of the balancing cylinders.This arrangement has made it possible to eliminate gaps in the positioning of the equipment.The HHM of the top roller of the feeder consists of two hydraulic cylinders. Hydraulic fluid is fed into the plunger chamber when the roller is to be lowered and is fed into the rod chamber when it is to be raised.Control Principles. Individual circuits have been provided (Fig.1) to control the hydraulic cylinders of the hold-down mechanisms.The control signal (Xctl) sent to the input of the servo valve is formed by a proportional-integral (PI) controller (to improve the sensitivity of the system, we chose to use valves with “zero” overlap).The signal sent to the input of the controller (the error signal Xerr) is formed as the difference between the control-point signal for position (Xcpt) and the feedback signal (Xf.b).The latter signal is received from the linear displacement gage (G) of the given hydraulic cylinder.The gages of the HHM for the top cassette are built into the balancing hydraulic cylinders (HCs).The cylinders are installed in such a way that their movements can be considered to be equal to the displacements of the corresponding cylinder rods, with allowance for certain coefficients.The gages in the HHM for the top roller of the feeder are incorporated directly into the hold-down cylinders.The integral part of the controller is activated only during the final adjustment stage and during stabilization of the prescribed coordinate.When the displacements exceed a certain threshold value, the functions of the PI controller are taken over by a proportional (P) controller with the transfer function W(s) = k.Thus, Xctl(t) = kXerr(t).When there are significant differences between the displacements of the working rollers,the difference (error)between the control point and the feedback signal from the linear displacement gage reaches values great enough so that the output signal which controls the operation of the servo valve reaches the saturation zone.In this case, further regulation of the displacement rate and,thus synchronization of the movements of the cylinders becomes impossible as long as the error exceeds the value at which Xctl is greater than the boundary value for the saturation zone (Xsat).The limiting errorthe largest error for which Xctldoes not reach saturationis inversely proportional to the gain of the controller k: Xerr Xsat/ k.Solving the given problem by decreasing k leads to a loss of speed in the adjustment of the PSM and a decrease in control accuracy during the straightening operation.Thus, to keep the control signal from reaching the saturation zone when there are substantial displacements, the system was designed so that the input of the controller is fed not the actual required value (Xrq) but an increment (X) of a magnitude such that the condition kX Xsat is satisfied.The control point is increased by the amount X after the position of the cylinder has been changed by the amount corresponding to the increment having the largest lag relative to the cylinders direction of motion. The adjustment of the control point is continued until the difference between the required value and the actual position of the mechanism becomes less than the increment:Xrq Xf.b X.Then the input of the controller is fed the value Xcpt, which is equal to the required adjustment: Xcpt= Xrq.The adjustment is thus completed.Use of the principle of a stepped increase in the control point makes it possible synchronize the movements of the cylinders and set the control point with a high degree of accuracy for almost any ideal repetition factor.Mechanisms for Individual Adjustment of the Working Rollers.The plate-straightening machine is designed so that each working roller can be moved vertically, which is done by means of a hydraulic cylinder acting in concert with a V-belt drive.The cylinders are supplied with power from servo valves operated with proportional control.A linear displacement gage is built into each cylinder to obtain a feedback signal on the position of the roller.Since these gages are actually transmitinginformation on the position of the cylinder rods rather than the working rollers themselves, the following conversion is performed to obtain the rollers coordinates:Xrol= kredXf.b,where kred is the gear ratio of the drive;Xf.b is the position of the cylinder rod measured by the linear displacement transducers. Thus, a position feedback circuit is provided to control the position of each working roller. Figure 1 presents a diagram of one of the circuits. The control signals are generated by means of the PI controllere, which has made it possible to achieve a high degree of accuracy in adjusting the system without sacrificing speed. The individual drive of the rollers. The above-described design is based on the use of individual ac drives with motors of different powers fed from frequency converters. Each individual drive offers the following advantages over a group drive:l greater reliability thanks to the absence of additional loads on the components of the mechanisms due to differences between the linear velocities of the working rollers and the speed of the plate;l the possibility that the machine could continue to operate if one or even several drives malfunction;in this case,the corresponding rollers would be removed from the straightening zone;l the possibility that the linear velocities of the rollers could be individually corrected in accordance with the actual speed of the plate;such a correction could be made either as a preliminary measure (on the basis of measured and calculated values) or during the straightening operation (on the basis of the data obtained from the frequency converters, which employ artificial intelligence). The main drive of the straightening machine rotates nine straightening rollers and two housing rollers.This drive must be highly reliable in operation, since the fact that the PSM is installed in the mill line means that sizable production losses can be incurred if the drive fails to work properly even for a short period of time. The requirements that must be satisfied by the drive are determined by the operational and design features of the machine as a whole:l the plate being straightened must create a rigid kinematic coupling between the straightening rollers, the rollers of the housing, and the adjacent sections of the roller conveyors;l the plate should undergo elongation during the straightening operation as a result of plastic deformation, with the increments in length being different on each working roller due to the differentiation of the bending radii;this situation leads to a nonuniform increase in the speed of the plate as it moves toward the end of the PSM;l it must be possible to use working rollers of different diameters (this being done, for example, due to nonuniform wear or regrinding);l the loads on the rollers should be differentiated in accordance with the chosen straightening regime;l reverse straightening should be possible. In light of the above factors and the actual operating regimes of the plate-straightening machine being discussed here, the following requirements can be established for the electric drive:l regulation of speed within broad limits, including startup of the motors under load;l operation in the reverse regime;l a rigid characteristic = (M);l high degree of accuracy in maintaining the prescribed speed;l fully synchronous operation. The element base. The drive of the rollers was built with the use of asynchronous three-phase motors having a short-circuit rotor.The motors were designed by the German company VEM.They can continue to function under severe overloads and are reliable in operation. The motors are controlled by SIMOVERT frequency converters made by the German firm Siemens.Their modular design facilitates maintenance and repair, and the presence of a built-in microprocessor block makes it possible to execute most of the functions involved in controlling the operation of the drive (maintain the prescribed speed with a high degree of stability, recalculate the frequency of rotation in accordance with the actual diameters of the rollers, diagnose the condition of the drive, control the drives operation, and exchange information on the PROFIBUS network). Motors of different powers are used in the system because of the differentiated distribution of the moments between the working rollers.Using different motors has made it possible to significantly reduce the cost of the electrical equipment and improve the performance characteristics of the machine as a whole. The machine has three main operating regimes: the working regime (semi-automatic and automatic), the transport regime, and the cassette replacement regime. Figure 2 shows a block diagram of the operations connected with realization of the working regime.In the semi-automatic variant of this regime, the operator controls the PSM from a control panel.In this case, the operator can do the following: choose the straightening regime from a database;correct the chosen regime;adjust the regime manually, which requires that the operator indicate the desired position of the bottom cassette (for five- or nine-roll straightening);adjust the gap between the top and bottom cassettes; set the coordinates for individual adjustment of the working rollers; choose the straightening speed and direction;generate a command to begin adjusting the machine to the specified regime. The machine is adjusted to the chosen regime automatically.After the adjustment is completed, a signal is sent to the control panel indicating that the coordinates of the mechanisms have been changed and that the rollers have reached their prescribed working speeds. In the automatic variant of the working regime, the plate-straigthening machine is adjusted on the basis of data sent through a data network from a higher-level system. These data include the following information:l the thickness of the plate being straightened;l the group of steels (information on the properties of the material);l the temperature of the plate at the inlet to the PSM.The PSM is adjusted in several stages:l preliminary adjustment based on the plate thickness and steel group, for cold-rolled plates (t = 20C);l further adjustment on the basis of data obtained from a pyrometer installed roughly 50 m from the PSM;l final adjustment on the basis of data obtained from a pyrometer installed at the entrance to the machine. In the automatic variant, control over the roller conveyors adjacent to the machine is switched over to the control system of the PSM as the next plate approaches the machine.In this case, the plate cannot enter the working zone of the machine until the adjustment is completed. If it is necessary to pass a plate through the machine without straightening it, the machine is changed over to the transport regime.In this case, the top crossarm and the cassette are elevated a prescribed amount and the speed of the rollers is changed so that it is equal to the speed of the adjacent roller conveyors. The cassette replacement regime is used in the event of breakage of a roller or when it is necessary to regrind the working and backup rollers.In this case, the operator can control the operation of the auxiliary mechanisms:the spindle-locking mechanism, the roll-out cart, the mechanism that locks the bottom cassette and the cart in position, and the hydraulic cylinder that moves the cart. The mechanisms are fixed in position by means of noncontact transducers. PSM Control System. Control of the plate-straightening machine required the development of a powerful, high-capacity system that could provide the desired control accuracy in combination with rapid operation.The control system that was created is divided into two levels: the base level, and an upper level.The diagnostic system was created as a separate system.A second controller was also provided, to control the pump station of the PSM.The base level of the control system employs a SIMATIC S7 industrial programmable controller, while the upper level and the diagnostic system were built on the basis of standard computers.The computer used for the upper-level system also serves as the control panel for the PSM. The different elements of the control system are linked by two loops of a PROFIBUS network (Fig.3).The first loop functions as the communications link between the controller, the upper-level computer, the diagnostics station, and the pump-station controller.The second loop links the PSM controller with the functional elements of the system (the frequency converters, linear displacement gages, and remote input/output module).The functions of the control system were divided between the base level and the upper level on the basis of the following principle: the base level was assigned all of the operations that involve receiving data from the sensors installed on the mechanisms, obtaining information from the automated process control system on the plate being straightened, and generating and transmitting control signals for the executive mechanisms (actuators); the upper level was assigned the functions of archiving the control points and monitoring the operation of the control panel.The following specific functions are performed by the base level of the automation system:l obtaining the assigned straightening parameters (roller speeds, the coordinates of the top crossarm, and the coordinates of the rollers relative to the crossarm) from the upper-level system;l processing the parameters and sending corresponding control signals to the actuators;l obtaining information from the sensors installed on the mechanisms to determine whether or not the PSM is properly set and ready for the straightening operation;l obtaining information from the feedback transducers installed on the mechanisms to calculate the control actions;l analyzing the readings of the sensors to determine the accuracy of the data;TABLE 1. Specifications of the Plate-Straightening Machinesl exchanging data with the pump-battery station (PBS) of the PSM and transmitting the stations operating parameters to the upper-level system for display;l receiving signals from the upper-level system for manual control of the machine and the PBS;l obtaining initial data from the upper-level system for automatic correction and transmission of the data in order to make the appropriate adjustments.The functions of the upper-level automation system are as follows:l entering data on the straightening regimes for subsequent selection of the regime and recording that information in a database;l manually choosing the straightening regime from the database for the corresponding plate (this is done by the operator);l automatically choosing the straightening regime from the database on the basis of information obtained from the upper-level system;l manually controlling the machine in the straightening and cassette-replacement regimes;l indicating the positions of the mechanisms based on readings from the sensors and the positions of the limit switches;l indicating the presence of a plate in the working zone of the PSM;l indicating the temperature of the plate measured by the pyrometer;l visual
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