你可能感興趣的試題

What is the purpose of a relief valve?（）

A.to fill 2 tanks at the same time
B.to use pump at a higher pressure
C.to return liquid to suction side if discharge valve is closed
D.All of the above are true

單項選擇題

A （） pump is that where the volume of the pump chamber is alternately increased to draw the liquid in and then decreased to force the liquid out.

A.injector
B.positive displacement
C.centrifugal
D.centripetal