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Wear occurring at the tips of the reduction gear teeth is usually the result of ______.
A.surface fatigue
B.fretting corrosion
C.heavy overloading
D.gear misalignment
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单选题Wear occurring at the tips of the reduction gear teeth is usually the result of （）.A
surface fatigueB
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heavy overloadingD
gear misalignment
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单选题Pitted reduction gear teeth having a deep blue color with evidence of overheating have been operated with （）A
excessive speedB
improper warm-upC
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