某固体火箭发动机点火器药柱断裂分析与改进

Crack Analysis and Improvement of Grain in SRM Igniter

针对某固体火箭发动机点火器加速老化后,在低温动力环境试验中部分产品的B/KNO3点火药柱断裂现象,采用故障树法对断裂的原因进行了排查,并通过压力试验、强度仿真等方法对其进行分析。结果表明:药柱支撑体与装药管体间较大的间隙和药柱支撑体排列的不合理,导致药柱在振动过程中出现应力集中区域,从而产生断裂。因此,提出了消除间隙、增加支撑体、优化支撑位置等改进措施,验证试验表明改进措施消除了药柱断裂现象。

Aimed at the problem that the grain of SRM igniter after accelerated aging test was cracked during impact and vibration test at low temperature, the fault tree analysis was carded out, and the reasons were analyzed by the pressure test and strength simulation. The failure analysis results showed that the large clearance between lip block and igniter case, as well as the unreasonable arrangement of lip block, make the stress concentration and the crack of grain during the impact and vibration test. The improvement measures like eliminating the clearance, adding lip blocks and optimizing the position of lip blocks were put forward, and the verification test indicated that the measures eliminated the crack phenomenon.