Closed-loop drawdown apparatus and method for in-situ analysis of formation fluids

摘要

An apparatus and method capable of incrementally decreasing the borehole pressure at a variable rate by controlling a test volume (405) within the borehole (204). The system includes an incrementally controllable pump (426), closed loop feedback (418, 424) and a controller (416) for drawing down the pressure of a test volume (405) to a level just below formation pressure. This incremental drawdown system will significantly reduce the overall measurement time, thereby increasing drilling efficiency and safety.