Derrick: the main hoist winch and a system of elevators lifts 1,250 tons of pipes and machinery through the 72.
钻塔：主起吊绞车和升降机系统可通过船底72英尺宽的开口，提升1,250吨重的管道和机械。
2
The air winch Operator shall ensure that the winch wire is moving freely in the derrick (possibly guided by pulleys) to avoid any damage to the steel structure, especially the fingerboard.