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