A.0.2mm B.0.3mm C.0.4mm D.0.5mm
A.杠桿夾鉗 B.電磁鐵 C.它動(dòng)夾鉗 D.大力鉗
A.滑輪和卷筒直徑過大 B.卷筒上繩槽尺寸和繩徑不相匹配,過小 C.滑輪槽底或輪緣不光滑有缺陷 D.潤滑不足,表面有灰塵或沙礫