A special device that,when fitted into the rotary table,transmits torque to the kelly and simultaneously permits vertical movement of the kelly to make the hole is called a().
A.
master bushing
B.
kelly slips
C.
kelly bushing
D.
rotary bushing
拍照语音搜题,微信中搜索"皮皮学"使用
参考答案:
参考解析:
知识点:
皮皮学刷刷变学霸
举一反三
【单选题】How is the information in the discussion organized?