结晶器振动装置中长臂的瞬态有限元分析

Transient Analysis of the Long-arm Used at the Libration Equipment in the Mold-oscillator

以直弧形四连杆型结晶器振动装置中的长臂为研究对象,利用模型切分方法,完成长臂复杂模型的全六面体网格划分,根据结晶器振动周期内前后两个半周期内不同作用力,运用有限元中分步加载的方法完成了一个周期内的长臂瞬态动力学分析。计算结果表明:在周期性交变载荷作用下,长臂的最小和最大综合应力的变化趋势几乎相同。二者后半周期的变化没有前半周期明显,且都存在极值波峰情况。在临界变化点时,波动差最大,极易使长臂产生破坏,因而在设计时应采用对长臂弯折处进行导角设计和局部增加筋板等方法以提高长臂的抗疲劳能力。

Based on the study for the long arm used at the libration equipment in the mold-oscillator in the four-link type straight-arc casting machine,the complex whole models hexahedral mesh was completed by the use of the model segmentation method.According to two kinds of different load under the mold oscillation libration cycle period,the transient dynamic analysis of the long-arm was carried out under one cycle period by the way of the carve-step finite element method.The results denote that under the periodic alternate load function,the changing trend of the minimum and maximum stress on the long-arm is almost the same.Their changing trend in the second half-cycle is not more obvious than that in the first half-cycle,but there is extreme wave value under the whole cycle period conditions.In the critical changing point,the fluctuating difference is the biggest and this can easily cause damage to the long-arm.So the chamfer required in the bending arc and adding partial ribs and other methods are considered to guide the long-arm design to improve its resistance to the fatigue.