液体火箭发动机用橡胶密封材料低温密封性能

为研究液体火箭用橡胶密封材料的低温密封性能，采用多种橡胶材料低温特征温度测试方法对液体火箭发动机常用的5种橡胶密封材料低温性能进行表征，在不同压缩率、不同工作温度及不同压差下对各橡胶密封材料在低温下的密封能力开展试验研究。建立橡胶密封圈仿真模型，分析橡胶密封圈在不同工作温度及不同压差的密封性能，并探讨其低温密封机制。研究结果表明：低温环境下橡胶低压缩率下的密封能力高于高压缩率下的密封能力；低温环境下由于橡胶的低温收缩和弹性模量急剧增大，在低压差下难以导致橡胶材料变形从而形成密封，须提高压差使得密封表面产生足够接触压力而形成密封。因此橡胶材料低温密封能力与材料低温收缩性能、弹性模量及压差相关，且工作温度超过橡胶低温下临界温度后，O形圈密封能力弱，易发生泄漏。

Low Temperature Sealing Performance of Rubber Sealing Material for Liquid Rocket Engine

In order to study the low temperature sealing mechanism of rubber sealing materials for liquid rocket,the low temperature performances of five commonly used rubber sealing materials for liquid rocket engines were characterized by various low temperature characteristic temperature testing methods of rubber materials.The sealing ability of various rubber materials at low temperatures under different compression ratios,working temperatures,and pressure differentials was studied by simulation analysis and experimental verification.The results show that the sealing ability of rubber under low compression in low-temperature environment is higher than that under high compression.In low-temperature environments,due to the sharp increase in low-temperature shrinkage and elastic modulus of rubber,it is difficult to cause the deformation of rubber material to form a seal under low pressure difference,and the pressure difference must be increased to produce enough contact pressure on the sealing surface to form a seal.Therefore,the low temperature sealing ability of rubber material is related to the low-temperature shrinkage performance,the elastic modulus of the material,and the pressure difference,and when the working temperature exceeds the critical temperature of rubber at low temperature,the sealing ability of the O-ring is weak and leakage is prone to occur.