泵前阀开关波纹管组件改进设计

Improvement of bellow assembly used as moving sealing unit of pre-pump valve

某型号发动机泵前阀在抽典试验中开关腔波纹管组件发生了疲劳失效,经对失效原因及机理进行分析,对波纹管组件进行了改进设计,并对原状态波纹管组件及新设计进行了有限元计算分析和疲劳寿命估计。计算结果表明,新设计波纹管应力分布相对合理,疲劳寿命水平有较大提高。设计改进后生产了试验件并进行了阀门试验,试验与计算结果相当并满足发动机使用要求。

In a sample test ofpre-pump valves for a certain rocket engine, the fatigue failure of the valve＇s opening-closing cavity bellow assembly occurred. The analysis result shows that the causation of fatigue is bi-directional bending fatigue rupture. Aiming at the problem of protraction and contrac- tion of the bellow assembly, some improvement on the bellow assembly, finite element analysis, bel- low trial-manufacture and bellow fatigue test were made. The results indicate the stress distribution of new bellows assembly is reasonable, the fatigue life increases greatly, The improved bellow was tested. The computation and the testing results are basically consistent and satisfied.