共查询到19条相似文献,搜索用时 93 毫秒
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皮带机跑偏原因及其处理方法 总被引:1,自引:0,他引:1
造成皮带跑偏的原因是多种多样的,有皮带机本身的内在因素,也有外界环境因素。但综合起来都是皮带两侧的驱动力不平衡及托辊、滚筒对皮带产生侧向力等因素造成的。 相似文献
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结合实例研究卷材运行过程中跑偏及跑偏控制原理,利用CCD灵敏度高、光谱响应宽、动态范围大、操作与维护方便等特点,提出基于线阵CCD的卷材跑偏在线检测与控制系统的总体设计方案,该检测与控制系统性能稳定,检测精度高,操作方便,具有一定的应用价值。 相似文献
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皮带机跑偏原因及其处理方法 总被引:1,自引:0,他引:1
造成皮带跑偏的原因是多种多样的,有皮带机本身的内在因素,也有外界环境因素。但综合起来都是皮带两侧的驱动力不平衡及托辊、滚筒对皮带产生侧向力等因素造成的。本文对此作一分析,供大家参考。 相似文献
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为实现车辆行驶跑偏量的高精度实时测量,针对测量误差大、重复性低的问题,运用GPS-RTK(卫星实时差分定位)技术进行车辆行驶跑偏量测量,将移动站接收机置于待测车辆上实时接收车辆位置信息,通过坐标转换软件转化为平面坐标计算跑偏量,同时建立车辆速度波动误差修正模型,将修正后的结果与传统陀螺仪检测结果进行对比。结果表明:车速的波动是导致车辆行驶跑偏量测量误差大、重复性低的主要因素,通过车辆速度波动修正模型修正后的百米跑偏量结果误差5 cm,且离散程度明显减小,提高检测的可重复性,实现车辆行驶跑偏量的高精度实时检测。 相似文献
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计算机仿真,是将被研究的对象按其特征抽象成模型,通过计算机技术对模型的仿真操作及仿真结果的分析,探讨和推断对象本身所具有的性质及其运动变化规律的一门综合性学科。民机性能工程中引入仿真技术可大大提高工作效率和计算准确性,为民机研制工作提供有力保障。本文针对典型性能仿真模型的建立方法进行了探讨。 相似文献
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本文主要讨论了气调包装系统原理.并建立了内环境动态变化模型。在此基础上将影响包装内环境的诸多参数进行分类.采用计算机仿真技术模拟出包装内环境三种气体浓度随时间的变化. 相似文献
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分析了热轧带钢生产过程中在精轧机组各机架间的温度变化过程,考虑机架间水冷综合换热系数对终轧温度的影响,提出了针对水冷综合换热系数的自适应策略.在现场实测数据的基础上,编制了精轧温度控制模型系数自适应计算的离线模拟软件,预先设定虚拟的通条带钢温度实测值,检验模型自适应系数的变化及其对下一次同规格带钢温度计算值的影响.计算结果表明,在本文建立的模型自适应策略下,自适应系数针对不同的轧件温度实测值可以进行迅速而有效的变化,使计算值迅速逼近实测值,表明本文建立的自适应策略有效. 相似文献
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基于对铜包铝双金属复合材料轧制变形过程进行的有限元模拟,建立了双金属复合材料轧制变形分区模型,可分为弹性区、单材料塑性区、后滑区、揉轧区和前滑区.以铜的体积分数为变量,对不同铜含量的铜包铝复合材料的轧制过程进行模拟,在单一材料轧制力理论计算公式的基础上,提出了双金属复合材料轧制力的理论计算公式,通过对铜包铝复合材料轧制的试验和不同压下率下的铜包铝双金属复合材料轧制成形的有限元模拟,对所推导出的轧制力公式进行了验证. 相似文献
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为研究热轧对7055铝合金淬透性的影响,采用末端淬火实验、硬度测试、光学显微镜和透射电镜研究了不同冷却速率处合金的组织和性能.实验结果表明:合金热轧后淬透性大大降低,淬透深度由约100 mm降至约45 mm,这主要与慢速淬火时析出的η平衡相的数量和尺寸的改变有关;热轧增加了η平衡相的形核位置,并引入大量的位错,增加了η平衡相的长大速率.因此,热轧合金固溶后慢速淬火时,析出的η平衡相的数量和尺寸都大大增加,时效后形成的η’沉淀强化相数量减少,硬度随冷却速率减小而下降的程度增加,合金的淬透性降低. 相似文献
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Miguel A. Cavaliere Marcela B. Goldschmit Eduardo N. Dvorkin 《International journal for numerical methods in engineering》2001,52(12):1411-1430
In this paper we discuss our finite element procedure for simulating the hot rolling of flat steel products. We couple an Eulerian rigid‐viscoplastic model of the steel plates deformation to a Lagrangian elastic model of the rolls deformation. This latter model incorporates the bending deformation of the work rolls supported by the back‐up rolls and the flattening of the contact areas (Hertz problem) via an enhanced beam model. The finite element model is validated comparing its predictions with actual industrial measurements and then it is used to analyse different rolling set‐ups. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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本文开展了变形温度为300、350、400 ℃和总压下率分别为15%、30%、45%、60%的AZ31B镁合金带材热轧试验,分析了不同工艺参数对轧后带材的微观组织及力学性能的影响规律。研究表明:随着轧制温度的升高,再结晶百分数增加,晶粒细化显著,组织均匀性增强;当温度达到350 ℃时,由于中间退火保温导致再结晶晶粒长大,使温度进一步升高,对再结晶程度的影响减弱,轧后带材晶粒度和延伸率均有降低;相比温度参数,提升总压下率对晶粒细化效果更为显著,轧制温度为300 ℃,压下率为60%时近表面平均晶粒尺寸由10 μm细化至3.7 μm,中心层晶粒尺寸细化至4.9 μm,组织分布较为均匀;压下率的增加有效改善了组织均匀性,使轧后带材延伸率显著增加,拉伸断口的韧窝增多,且逐渐加深。 相似文献
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This paper aims to address the issue of fluctuations of copper rod diameter during the process of hot rolling. In addition, it proposes a solution to control the diameter of the copper rod in order to improve the quality of the hot rolling mill products. The change of copper rod diameter during the process of hot rolling results from disturbance effects (such as temperature, torque loading, and plant ageing) which leads to the deterioration of product quality. To overcome changes in the copper rod diameter, a proportional-integral-derivative (PID) based on a particle swarm optimization, auto tuning diameter controller was designed to reduce the fluctuations in the rod diameter and different control techniques with variable structure PID controllers were proposed, evaluated, and compared by extensive simulation tests. The PID diameter controller was designed based on the experimental data that showed that the speed of the rolls leads to sensible differences in the copper rod diameter. It was also designed to guarantee that the synchronization between the stands of the rolling mill is maintained so that the metal flow rates from the first stand to the last one is kept constant. Moreover, it was designed in a way which assures that the tension of the cast bar will remain unchanged and does not conflict with the tension controller. The design of the diameter controller, modeling, validation, verification and simulation of the rolling mill process is presented, which involves the reduction of the copper rod diameter by passing the hot cast bar through a preset roll gap between two work rolls that are driven by a DC motor. A proposed combined-control of motor speed and rod diameter controller reduces fluctuations in the rod diameter. 相似文献
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A macro- and micro-combined model has been developed to simulate the static and dynamic recrystallizations of austenite during hot rolling of steel. In addition to the coupled thermal and mechanical phenomena, a micro-constitutive relationship is used to link the macro and micro models. The macro model provides the thermal and deformation information for the micro model. A finishing line with seven stands is studied to verify the model's reliability. The results indicate that static recrystallization plays a more important role than the dynamic part in austenite refinement. 相似文献