oiltight
1. oiltight bulkhead
不渗油舱壁
2. conic oiltight hatchcover
圆锥形油密舱口盖
3. An oiltight bulkhead
油渗不进的舱壁
4. Analysis on Combinatory Seal of Back Blade and Oiltight
背叶片与油封的组合密封特性分析