(北京科技大学 机械工程学院,北京 100083)
摘 要: 针对目前金属镁热还原工序中人工装出料的现状,提出采用无轴螺旋体作为罐内执行机构的机械装出料方式。通过理论设计计算确定螺旋体的结构、尺寸和运动参数,采用ANSYS有限元分析螺旋体的整体弯曲和扭转性能,以保证机构设计参数合理并具有良好的机械性能。研究表明:通过对叶片截面温度场的分析发现,叶片在工作时间内的温升在材料的允许范围内,验证所选叶片材质的合理性;通过对螺旋体的应力分析,发现自由端叶片和螺旋内径处为薄弱环节,提出螺旋体自由端的缩径结构和外窄内宽的梯形叶片截面。采用本机构进行机械化装出料,可将装出料时间由2 h缩短为15 min,大大缩短热还原工序的时间,具有实际推广和应用价值。
关键字: 镁热还原;高温装出料;机械化;无轴螺旋
(School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China)
Abstract:In traditional thermal reduction process of magnesium, charging and discharging were carried out in manual operation. Based on this, the screw structure without shaft was proposed as the actuator inside the reduction jar. The corresponding structure sizes and motion parameters were determined by theoretical calculation. The bending and torsion stress were analyzed by the finite element analysis of ANSYS software, which can guarantee feasible parameters designed and good mechanical property of the structure. By analyzing the temperature distribution of blade section, the temperature changes of blade during the working time are in the range of material allowed, which proves that the blade material is available. The blades at free end and at inner periphery are weak by the stress analysis. Therefore, a diameter shrinkage structure at free end and blade with trapezoid cross section are presented. The results show that, by applying the screw structure without shaft, the time for charging and discharging is shortened from traditional 2 h to 15 min, which shows the designed structure with practical value is worth popularizing.
Key words: thermal reduction of magnesium; high-temperature charging and discharging; mechanization; screw structure without shaft