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... 阶梯状断面油环 stepped oil control ring 具有锯齿状或粒状断口的 hackly granular 细粒 drib; f g; fine grain-size; fine particle; fine texture; fines; granule =pellet =grain; granule=peuet=grain; hydatid tapeworm; particulate; pea; slime concentrate; speck ...