深海高压环境, 密封圈, 自压缩特性, 高压试验 

The deep-sea experimental instruments' sealing performances are influenced by the self-compressibility under high pressures.The authors deduced the formula of calculating the axial compression ratio,and did the axial compression experiments on the following three kinds of sealing materials: fluorine rubber, silicone rubber and nitrile butadiene rubber, which shows the self-compressibility of sealing materials is less than 6% under the deep-sea high pressure (10 000 m means 100MPa). Therefore the principles of designing sealing structures at atmospheric pressure can be adopted(sealed slot, O-ring selection, etc.);however,the O-ring equivalent diameter should be appropriately enlarged by 10% for the sake of security.