Method for deploying extendable arm for formation evaluation MWD tool

摘要

An extending arm is incorporated into a formation evaluation MWD collar or sub for extending outwardly from the tool and maintaining direct and continuous contact with the borehole wall (e.g., formation). In accordance with this invention, a method is presented for intermittently deploying the extendable arm and thereby decreasing drilling interference (caused by the arm) and avoiding the damage caused by accidents involving a nuclear source.