超音波法液位元元元元元元测定
ultra-sonic method of liquid meaduremert
WES溢流重力坝
gravity overflow dam with WES profile
泵溢流压力检验
pump relief pressure check
比例压力溢流阀
proportional pressure relief valve
比例溢流阀
proportional relief valve
Proportional pilot valve
闭式燃油溢流系统
closed fuel overflow system