短語(yǔ)詞組短語(yǔ)elevator bottom split ring 陞降機(jī)開(kāi)口環(huán)bottom piston ring 下麪的活塞環(huán)bottom ring bottom cover 底環(huán)bottom ring wall plate 底圈壁板BOTTOM RING SEAT 底座bottom ring modified 底環(huán)脩飾BB bottom ring 基帶refractory bottom ring 耐火底環(huán)bottom ring of staying 座環(huán)的下環(huán) 返回 bottom ring