单选题What is the function of wearing rings found on some centrifugal pumps? （）AAbsorb erosion of high velocity discharge streamBSeal pump shaft against entry of airCIsolate the outlet side from the inlet sideDDampen the turbulent discharge flow
单选题
What is the function of wearing rings found on some centrifugal pumps? （）
A
Absorb erosion of high velocity discharge stream
B
Seal pump shaft against entry of air
C
Isolate the outlet side from the inlet side
D
Dampen the turbulent discharge flow
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