单项选择题
A.discharges into a gradually widening channel B.has stationary diffuser vanes C.produces no kinetic energy D.All of the above are true
Which of the following pumps belongs to centrifugal pum...
单项选择题Which of the following pumps belongs to centrifugal pump?（）
A.Piston pump B.Screw pump C.Diffuser pump D.Water-ring pump
The pump discharge pressure will be considerably higher...
单项选择题The pump discharge pressure will be considerably higher than the pressure at the （）.
A.pump entry branch B.outlet pipe C.impeller D.None of the above is true
What is the purpose of a relief valve?（）A.to fill 2 tan...
单项选择题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
