天然气平板闸阀的有限元应力分析及结构改进

为了研究某闸阀发生开裂事故的原因,利用有限元方法对闸阀结构进行了应力分析.根据闸阀结构二维图纸的相关参数,运用三维建模软件建立闸阀的几何模型;将几何模型导入有限元分析软件ANSYS的仿真平台Workbench,建立闸阀的有限元分析模型;以闸阀的实际工作情况为依据,对闸阀的有限元分析模型施加边界条件,计算出闸阀的应力分布.闸阀的应力分布结果显示,闸阀在其凸台结构处具有应力集中现象且闸阀的最大应力也出现在凸台结构处,易引起闸阀凸台处的开裂.为了缓解闸阀凸台结构处的应力集中现象,对闸阀结构进行改进,去掉闸阀上引起应力集中的凸台结构.改进后的闸阀有限元应力分析表明：其最大应力值比改进前降低了37％左右,能更好地保证闸阀的安全使用.

Stress analysis of finite element and structure amelioration on natural gas plate valve

To explore cracking accident of a plate valve,finite element method was used to analyze the stress of the plate valve structure.Based on the relevant parameters of two-dimensional drawing of the plate valve,a three dimensional software（Solid Works） was used to establish geometrical model of the plate valve.The geometrical model was then imported in the ANSYS Workbench to establish finite element model.Based on the actual working situations of the plate valve,the loads were exerted on the finite element model to calculate the stress distribution of the plate valve.The results show that both the stress concentration and the maximum of stress value are emerged on the plate valve boss,so the cracking would be caused by the plate valve boss.To relieve the stress concentration,the plate valve was ameliorated by removing the plate valve boss.The finite element analysis of the ameliorated plate valve shows that the maximum stress is lower 37％ than that of the original.Therefore,the ameliorated plate valve can be more secure to be used.