OBERE ANTRIEBSEINHEIT, ROHRGREIFVORRICHTUNG UND VERFAHREN ZUM BOHREN EINES BOHRLOCHS

摘要

A top drive unit comprising a top drive (20) and a pipe gripping device (50; 110) connectable beneath said top drive (20) , the arrangement being such that, in use, whilst a pipe is connected to said top drive (20) said pipe gripping device (50; 110) is moveable between a first position in which said pipe is accommodated within said pipe gripping device (50; 110) and a second position in which said pipe is not accommodated within said pipe gripping device (50; 110).