A.比轉(zhuǎn)數(shù)=50 B.比轉(zhuǎn)數(shù)=100 C.比轉(zhuǎn)數(shù)=250 D.比轉(zhuǎn)數(shù)大于300
A.金屬填料密封 B.機(jī)械密封 C.迷宮式密封 D.浮動(dòng)環(huán)密封
A.閉式葉輪 B.半開式葉輪 C.全開式葉輪 D.不能確定