沥青搅拌设备振动筛防堵模型与试验研究  

Anti-blocking model and experimental research on vibrating screen of asphalt mixing plant

作　　者：刘洪海[1] 曾凡记 程旭[1] 周峰[1] 

机构地区：[1]长安大学道路施工技术与装备教育部重点实验室,陕西西安710064

出　　处：《广西大学学报（自然科学版）》2015年第2期382-388,共7页Journal of Guangxi University（Natural Science Edition）

基　　金：国家十二五科技支撑项目(2011BAE28B03);教育部中央高校基本科研业务费专项资金资助(2014G3252006)

摘　　要：沥青混合料搅拌设备振动筛的筛分效率决定了混合料生产级配的稳定性,堵筛会使筛分效率发生变化。为了研究堵筛问题,通过对振动筛的结构、工作机理和运动特性分析,建立了振动筛的运动学模型,确定了振动参数与偏心块质量、振动筛质量、当量转动半径等参数之间关系;通过对堵筛条件下颗粒的运动特性和动力学分析,分别建立了刚性筛网和弹性筛网的力学模型,分析了振动筛的动力学参数、材料的物理特性、筛孔尺寸和筛网刚度等参数对堵筛的影响。实验结果表明,对5 mm×5 mm的刚性筛网方孔筛,在常规设计的振动筛频率16 Hz和振幅5 mm下堵筛率较大(大于10%),堵筛颗粒的逃逸能力较低。因此,当筛孔尺寸小于6mm时,需要提高振动强度改善堵筛率;为了避免提高振动参数增加技术难度或影响设备结构强度,采用刚度小的弹性筛网是最佳解决方案。The stability of production gradation of mixture is determined by the screening efficiency of vibrating screen of asphalt mixing plant, and the blocking sieve may result in the change of effi- ciency. To study the problem of blocking sieve, a kinematics model of vibrating screen is established and the relationships of vibration parameters, the qualities of eccentric block and vibrating screen, and equivalent rotation radius are determined by analyzing the structure, working mechanism and motion characteristics of vibrating screen; mechanical models of rigid sieve and elastic sieve are established respectively and the influence of parameters of vibrating screen, such as kinetic parameters, physical properties of the material, the size of vibration sieve mesh and mesh stiffness, on blocking screen is explored by analyzing the motion characteristics and dynamics of particles under the condition of blocking screen. The result shows that the blocking rate of 5 mm × 5 mm rigid square-hole vibration screen is larger （ more than 10% ） , and the escape ability of particles is relatively lower under the conventional design of frequency （16 Hz） and amplitude （5 mm）. There fore, it is necessary to raise the vibration strength and to reduce the blocking rate when the mesh size is less than 6 mm ; the elastic sieve of a smaller stiffness is the best solution to avoid increasing tech- nical difficulties or affecting the structure strength of equipment as a result of the increased vibration parameters.

关 键 词：道路工程 振动筛 堵筛 数学模型 沥青搅拌设备 

分 类 号：U415.52[交通运输工程—道路与铁道工程]