Used to rotate the drill string during the drilling process, the top drive is a motor that is suspended from the derrick, or mast, of the rig. These power swivels boast at least 1,000 horsepower ...

Feb 21 (Reuters) - U.S. energy firms this week added oil and natural gas rigs for a fourth week in a row to the highest level since June, energy services firm Baker Hughes (BKR.O), opens new tab ...