固体火箭发动机橡胶密封结构可靠性试验及评估方法

Storage reliability test and evaluation method for rubber seal structure of SRM

由于关系到固体导弹的首翻期,“O”形橡胶静密封结构可靠性一直是固体火箭发动机寿命研究的重要内容。在梳理和分析密封结构全寿命周期剖面中长期贮存、快速点火升压和短时间工作平衡这三个典型阶段载荷及其变化的基础上,以密封接触应力为表征参数,基于应力-强度干涉模型建立了重点考虑前两个阶段的密封结构可靠性评估方法。为快速准确模拟第一阶段密封结构的贮存性能变化过程,采用了步进应力加速贮存试验项目;为获得第二阶段的密封结构可靠性的广义强度和应力,提出了密封面张开速率及回弹过程密封接触应力测试项目,构成了密封结构全寿命周期可靠性试验方法。据此,开展了F108“O”形密封结构的贮存试验和评估,验证了该方法的可用性和准确性。

The storage propriety of seal structure is always an important content in SRM’s life research due to its significance to the first restore period of solid missile.On the basis of sorting out and analyzing the loads and their changes of the sealing structure in the whole life cycle profile during the typical stages of long-time storage,fast ignition pressurization and short time load balance,a reliability evaluation method was established using the sealing contact stress as the characterization parameter based on the stress-strength interference model,which mainly considered the first two stages.In order to quickly and accurately simulate the changing process of the seal structure storage performance in the first stage,a step stress accelerated storage test item was adopted.For obtaining the generalized strength and stress of sealing structure reliability in the second stage,the test items of sealing surface opening rate and sealing contact stress during rebound resilience process were proposed,and the life-cycle reliability test method of sealing structure was constituted.The storage test and evaluation of F108“O”shaped seal structure were carried out,and the availability and accuracy of the method were verified.