AA9-683阀门活门杆失效分析

Failure analysis on stem of valve AA9-683

试验中大量使用的AA9-683阀门多次出现活门杆弯曲卡死现象。依据阀门工作原理和故障活门杆分解情况对活门杆失效机理进行分析认为:活门杆弯扭屈曲可能为临界载荷和侧向载荷共同作用产生的结果。选取最小截面等截面法和仿真计算法分别计算活门杆临界载荷。最小截面等截面法依据欧拉临界载荷公式获得临界载荷,仿真计算法依据ANSYS Workbench软件基于静力法的屈曲计算方法获得临界载荷。通过比较2种方法计算的临界载荷数据,显示结果接近,并且依据已测量挠度以及挠度计算法推导出侧向载荷。将临界载荷、侧向载荷结果与活门杆失效情况比较分析,得出活门杆失效机理的分析结论成立。针对造成活门杆失效的原因采取了有效的改进措施。

The stem of valve AA9-683 bending and clamping phenomenon occurred repeatedly in the test. According to the valve working principle and fault stem decomposition, and the failure mechanism analysiss of the valve stem, it is considered that the stem flexural torsional buckling may be generated by the combined action of critical load and lateral load. The minimum cross section uniform method and simulation calculation method are chosen to calculate the critical loads of valve stem respectively. The former obtains the critical load according to Euler critical load formula, and the latter obtains the critical load according to the static method based buckling calculation method of ANSYS Workbench software. By comparing the critical load data got by the two methods, the results are close to each other. According to the measured deflection and the deflection calculating method,the lateral load can be deduced. The relation of the critical load and lateral load with the actual results of the valve stem failure are compared and analyzed. The results indicate that analysis conclusion of the valve stem failure mechanism is tenable. In view of the failure causes of the valve stem, effective measures were taken.