共查询到20条相似文献,搜索用时 140 毫秒
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《机械设计与制造》2016,(12)
首先根据现有四辊方管轧机机架尺寸数据建立方管成型机组的三维模型,之后把工厂的生产经验和张力减径理论相结合确定机组各项工艺参数。应用显式动力学分析软件对三架方管轧机轧制过程进行仿真,求得钢管所受最大压力大小及出现的时间、位置,从而结合轧制力计算公式得到各架轧机所受轧制力范围。之后把最大轧制力导入有限元软件,对四辊轧机机架进行有限元分析,得到机架在最大轧制力作用下的应力应变分布规律,从而改进机架的薄弱结构,并把改进结果导入有限元软件中进行对比分析。最终在降低机架等效应力的同时,有效降低了机架的自重,且机架变形量增加很小。从而使机架性能得到改善,同时降低了生产成本。 相似文献
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马竹梧 《世界仪表与自动化》2005,9(12):21-23
图4列出了西门子公司的H型钢粗轧机小张力控制系统结构图,粗轧机由3台轧机组成,包括1#万能粗轧机(UR1)、轧边机(ER)以及2#万能粗轧机(UR2)。H型钢万能粗轧机组张力控制采用下游调节方式,当UR1-UR2方向轧制时,以UR1机架为基准,调下游机架速度基准值,使机架问的张力达到设定值:当UR2-UR1方向轧制时,则以UR2机架为基准,同样调下游机架的速度基准值来获得设定的机架间张力。 相似文献
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四辊轧机辊系偏移距机理的不确定性和微尺度静定性 总被引:1,自引:0,他引:1
生产板带的四辊轧机辊系,普遍设置偏移距求得轧辊间平行定位及其稳定以防止辊间交叉,成为四辊轧机辊系平行定位机理编入轧机教科书及参考书中。近代相继出现的现代四辊轧机辊系都设置偏移距,但未能保证其机理的确定性,辊间动态交叉现象的发生屡禁不止,引发超大轴向力损坏推力滚动轴承或生成轧制支反力偏差破坏板形控制的稳定性。设置偏移距3mm的高速铝箔四辊轧机轴向力在线检测试验,揭示轧制过程中工作辊与支承辊之间发生规律性动态交叉现象。轧制中轧辊之间的动态交叉行为,与轴承座和机架窗口立柱间微小间隙大小相对应,只限于轧机的交叉角β≤0.05°区间,远小于交叉(Paircross,PC)轧机的交叉角(β=1°~1.5°),但派生的轴向力超出额定值的3倍以上。四辊轧机模拟辊系偏移距静态零调试验,探明轧辊间初始安装位置不变没有轧辊的水平位移。辊间动态交叉现象和静态水平位移为零的两种结果,揭示出设置偏移距机理的不确定性,不能用于四辊轧机辊系平行定位及稳定性设计。 相似文献
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宽带钢冷连轧机综合耦合模型的建立与分析 总被引:2,自引:0,他引:2
宽带钢冷连轧过程中,板形、板厚和张力控制之间存在着很强的耦合关系,相互影响对方的调节功效。为了进一步提高控制精度,进行解耦设计实现解耦控制是十分有效的手段,而其前提和基础就是冷连轧机综合耦合模型的建立和分析。首先,运用轧制理论对轧制过程中板形、板厚和张力控制的各种影响因素进行了系统的分析,然后考虑执行内环的动态特性建立冷连轧机综合耦合模型,以定量地描述轧制过程中辊缝、弯辊力、本架轧辊速度、前架轧辊速度和出口厚度、出口凸度、出入口张力之间的耦合影响关系。最后,基于Matlab/Simulink工具,采用此耦合模型对某冷连轧机末机架的耦合特性进行仿真分析,指出对其进行解耦控制的必要性。 相似文献
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针对3000mm中板四辊可逆轧机机架辊生产过程中易出现的各类设备故障:轴承寿命短、传动易失效等具体问题,结合现场生产条件,经过多次摸索、试制对机架辊结构进行了改造优化,收到了实际成效,实现了三钢中板轧机机架辊的使用寿命由4~6个月延长至10~12个月。 相似文献
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浅谈冷轧机电气控制中的张力控制 总被引:1,自引:0,他引:1
王志为 《机械工程与自动化》2007,(1):142-144
阐述了张力的概念、张力在轧制过程中的作用、张力控制原理以及影响张力波动的因素。 相似文献
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马健儿 《机械制造与自动化》2005,34(6):47-51,54
主要分析了一种较新的张力控制系统——复合张力控制系统,即将普通的直接张力控制和间接张力控制方法结合在一起,分阶段进行张力调节,起到了很好的控制作用。 相似文献
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The problem of real-time tension control in a metal-strip processing line is addressed. The tension in a metal strip changes
due to not only the speed difference but also thickness changes at the ends of a span. The mathematical dynamic model which
describes relationship between the tension change and the roll-speed change is improved to include the effect of the strip
thickness change on tension variation. Through the computer simulation of this model. the parameter sensitivity analysis and
the static and dynamic characteristic study are carried out. The tension variation in a metal strip turned out to be very
sensitive to the thickness variation as well as to the speed difference at the ends of the metal strip. In the rolling process,
the master speed drive is usually located at the last stand. The speeds of rollers in upstream stands are adjusted with respect
to the speed of the last stand to compensate the speed change for the tension regulation. A new tension control strategy in
a multi-stand rolling process is suggested. The tension transfer phenomena is used in the design of the suggested controller.
The developed mathematical model is used to design a controller for the real-time control system. A set of requirements for
the real-time tension control is suggested. Based on the requirements, a real-time software for the tension control in a multi-stand
system is designed and real-time simulation was carried out by using the Vx Works real-time scheduler and the Force Target
board. The cancellation mechanism of the roll gap control due to the tension interaction is clearly defined by using the mathematical
model derived in this study. It is confirmed that the suggested control strategy needs less control efforts and shows better
performance than those of the existing control method in a rolling process. 相似文献
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介绍冷轧薄板生产线上卷取机张力设定原则及计算方法,着重说明如何利用摩擦补偿、惯量补偿等动态补偿功能,使卷取机在轧制过程中保持稳定的恒张力工作状态 相似文献
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在冷轧生产中,施加张力是调整板形、保证轧制过程顺利进行的重要手段。利用张力不仅可以改善板形、调节轧机负荷,同时还可以通过调整轧机前后张力来改变带材的前滑量,进而控制带材表面质量。由于张力在轧制中的上述作用,决定了张力制度是冷连轧轧制制度中一项很重要的工艺制度。为了准确的进行张力设定,在冷连轧二级系统中通常采用模型回归法或表格法作为张力模型的建立方法。 相似文献
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提出了一种新型的络筒张力控制系统,该系统在控制模块采用了模糊控制策略,使系统具备了良好的控制效果和稳态精度。并建立了系统数学模型,进行了计算机仿真研究。 相似文献
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热车板是以板坯为原料,经加热后由粗轧机组及精轧机组制成带钢,从精轧最后一架轧机出来的热钢带通过层流冷却至设定温度,由卷取机卷成钢带卷。通过论述卷取电机的速度与张力控制原理,结合PLC控制,实现对热轧卷取的高精度控制。 相似文献
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Safe operating environment is essential for all complex industrial processes. The safety issues in steel rolling mill when the hot strip passes through consecutive mill stands have been considered in this paper. Formation of sag in strip is a common problem in the rolling process. The excessive sag can lead to scrap runs and damage to machinery. Conventional controllers for mill actuation system are based on a rolling model. The factors like rise in temperature, aging, wear and tear are not taken into account while designing a conventional controller. Therefore, the conventional controller cannot yield a requisite controlled output. In this paper, a new Genetic-neuro-fuzzy hybrid controller without tension sensor has been proposed to optimize the quantum of excessive sag and reduce it. The performance of the proposed controller has been compared with the performance of fuzzy logic controller, Neuro-fuzzy controller and conventional controller with the help of data collected from the plant. The simulation results depict that the proposed controller has superior performance than the other controllers. 相似文献