短语词组短语ball float collar 球形浮箍ball collar thrust bearing 滚珠环止推轴承;[机]滚珠环推力轴承;环形球推力轴承;滚珠环止推ball collar tbearing 油膜轴承concentrated ball collar 密珠套ball collar thblight bearing 滚珠环止推轴承 返回 ball collar