“一个流”U型生产线的平衡分析和改善

"一个流"U型生产线平衡率过低会造成在制品积压、阻塞、误工误时等,最终导致生产效率和产能降低。结合某公司精益提升项目,阐述了作业路线最优化、操作动作规范化、工装夹具自动化是"一个流"U型生产线提高可动率的有效途径,也是生产线平衡分析和改善的重点。     

水阀内置流量传感器旋转叶片的受力模型研究

为了从理论上分析所设计的水阀内置流量传感器的测量精度,本文在对叶片所受驱动力矩及阻力矩进行深入分析的基础上,建立了传感器旋转叶片的受力模型,为水阀内置流量传感器的设计奠定了理论基础.     

芳烃抽提系统叶轮的失效分析

采用微库仑法、光谱法、光学显微镜、扫描电镜、X射线衍射仪等手段对芳烃抽提系统的3105泵叶轮进行了失效分析。结果表明,叶轮失效的主要原因是材料组织粗大以及氧腐蚀和冲蚀磨损交互作用的结果。     

热控系统可靠性分析与对策

从就地控制设备、二线线路、控制电源、控制装置 (卡件 )、拌热情况、人员问题等几个方面对全省热控系统存在的问题及影响机组可靠性的隐患进行技术分析及对策的探讨     

一种适用于车用增压器涡轮的前弯后掠式叶轮

本文给出了车用增压器涡轮叶轮的一种新型结构——前弯后掠式叶轮。这是针对车用增压器涡轮的实际工作条件以及常规叶轮的不足，基于叶轮内部流动改善以提高涡轮的变工况适应性而提出的。文中详述了新型叶轮的设计思想及其理论和实验依据，并通过数值试验证明了前弯后掠式叶轮较常规叶轮在气动热力学机理上的改进。     

径流式涡轮前,后弯叶轮特性的数值分析和试验研究

研究了车用增压器径流式涡轮的前弯和后弯叶轮的特性，以揭示叶轮进口不同型线对其内流特性及涡轮变工况性能的影响，文中给出了应用时间推进全三元Ｅｕｌｅｒ解方法得到的叶轮内部流场以及在径流式涡轮试验台上测得的级性能参数，同时对不同叶轮的数值分析和试验研究结果进行了讨论和比较。     

可展曲面后掠叶片离心式压气机叶轮造型方法图形绘制和三元流场计算分析

给出一种可展曲面后掠叶片离心式压气机叶轮选型方法。叶轮叶片的压力面吸力面均为可展曲面，可消除加工叶轮叶片面的干涉现象。采用叶片周线表示叶片，画出的叶轮轴向轴测投影图形，可证明此方法是可行的，使用真实感图形绘制的叶轮图形具有更强的立体感和真实感。此外，应用准正交面法计算一组叶轮的三元流场，叶轮流场较好，压气机可望取得较优的性能。以上研究成果为这种压气机叶轮的研制提供了理论基础，为离心式压气机叶轮计算机辅助设计增添新内容。     

Stage-wise characterization of the high shear granulation process by impeller torque changing rate

Fine cornstarch powders are wet granulated in a lab-scale high shear granulator. The torque required for maintaining the impeller passing through the bed with a constant rotating speed is monitored during the continuous binder addition granulation process. A new method is proposed to identify 6 stages during the granulation process based on the fraction of the positive impeller torque changing rate in a characteristic period of time. The morphologies and the behavior of the bed are found intrinsically different in the identified 6 stages. The influence of the impeller blade inclined angle on the impeller torque in each stage is initially reported. The impeller with planner 45° blades requires higher torques in Stages I and II due to the overall powder bed mass loading. The impeller with steeper 60° blades requires higher torques in Stages III and IV due to the higher collision frequencies between the blade and granules. The suitable granulation liquid binder to solid powder mass ratio can be readily identified in Stages II and III, and its range is found to increase with the increasing of the impeller rotational speed and is independent to the blade inclined angle.     

DEM study of the effect of impeller design on mixing performance in a U-shape ribbon mixer

The mixing of powders in a U-shape mixer is significantly influenced by the mixer design, especially impellers, but the studies on the mixing processes are still insufficient. In this study, the effect of impeller designs on mixing performance in an industrial-scale U-shaped ribbon mixer is studied using DEM simulations. Three impeller designs are studied: 2-bladed impeller spiralling in the same direction (i.e., Design I) and the opposite direction (i.e., Design II), and 4-bladed impeller (i.e., Design III). Different particle mixing behaviours in three different impeller designs are studied in aspects of mixing status, particle path line, velocity distribution, and forces. The radial direction has the highest dispersion coefficient while the axial direction has the lowest dispersion coefficient. Most particles in the mixers are imposed a weak force. Design III shows the best mixing performance among the three with the front-by-back and top-by-bottom loading used. Design II shows a better mixing performance used than Design I and III with the side-by-side loading but takes a longer time to reach the stable status. This work evaluates the effect of different impeller designs on the mixing performance in an industrial-scale U-shaped ribbon mixer and provides an effective way to assist industrial design in an economical and safe manner.