A.0.2~0.4MpaB.2~4MPaC.7~8MPaD.5~6MPa
A.氣動(dòng)絞車(chē)B.套管扶正器C.鉆井絞車(chē)D.載人絞車(chē)
A.時(shí)期B.特征C.程度D.期限