单选题A centrifugal bilge pump requires priming （）.Aprimarily to lubricate the shaft sealsBdue to the inability of this type of pump to lift water to cover the suction (eye) of the impellerCto initially unload the pump by having its head pressure equal to discharge pressureDin order to overcome the potential energy of water in the discharge line
单选题
A centrifugal bilge pump requires priming （）.
A
primarily to lubricate the shaft seals
B
due to the inability of this type of pump to lift water to cover the suction (eye) of the impeller
C
to initially unload the pump by having its head pressure equal to discharge pressure
D
in order to overcome the potential energy of water in the discharge line
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