ventilation shaft
短语词组
- piston ventilation shaft layout 活塞風井設置
- ventilation of mine shaft 鑛井通風
- south ventilation shaft 南風井
- surface mine ventilation shaft 地麪風井
- uranium mine ventilation shaft 鈾鑛井通風
- emergency ventilation shaft 事故通風井
- a ventilation shaft 排氣孔
- tunnel l ventilation shaft 隧道通風井
- ventilation shaft reconstructing 風井改造 返回 ventilation shaft