downhole closed-loop 井下闭环
Steering tools are essential part of steering drilling system and one of key factors for fulfilling downhole closed - loop drilling.
导向工具是导向钻井系统的核心，是实现井下闭环钻井的关键因素之一。
The steering assembly is the key tool of the downhole closed-loop drilling system, and its mechanics properties are the base of downhole closed-loop control.
作为井下闭环钻井系统核心部分的下部导向钻具组合的力学特性，则成为形成井下闭环控制的基础。
It is necessary to depend on the control technology of borehole trajectory to drill the extended-reach well successfully. A closed-loop adjustable stabilizer at downhole is developed.
钻成大位移井必须依靠井眼轨迹控制技术，研制的井下闭环可变径稳定器是实现该项技术的关键。
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