单选题One of the main functions of wearing rings, as used in a centrifugal pump, is to （）.Amaintain radial alignment between the pump impeller and casingBabsorb all impeller shaft end thrustCprevent water leakage to the atmosphereDprevent wear of the pump casing and/or impeller
单选题
One of the main functions of wearing rings, as used in a centrifugal pump, is to （）.
A
maintain radial alignment between the pump impeller and casing
B
absorb all impeller shaft end thrust
C
prevent water leakage to the atmosphere
D
prevent wear of the pump casing and/or impeller
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