差速器机油油位目测表
differential oil level sight gauge
动力定位油轮
dynamically positioned tanker
发动机机油油位指示器灯
engine oil level indicator lamp
发动机曲轴箱机油油位
engine crankcase oil level
恒定油位润滑
constant-level lubrication
恒定油位润滑器
constant level lubricator
曲轴箱机油油位表
crankcase oil level gauge