DERRICK HAVING DUAL TOP DRIVE

摘要

PURPOSE: A derrick with a dual top drive is provided to minimize an occupied area on a deck by simplifying the structure of the derrick. CONSTITUTION: A derrick with a dual top drive comprises a rotary member(110) and first and second top drives(130,140). The rotary member is hinged on the top end of the derrick. Fixed pulleys(112,113) are installed on both sides of the rotary member. The first and second top drives are connected to both sides of the rotary member through wires(121,122) and grip drilling pipes(200) through the winding and unwinding of the wires.