Downhole core barrel flushing system

Abstract

A core barrel flushing device and method is disclosed particularly for flushing drilling fluid, mud and other undesirable material from a pressure core barrel downhole at existing conditions and pressure. The flushing device (F) comprises an outer barrel attachable to the drill string and core barrel (10), and an inner barrel (90) within the outer barrel (70). A sealed chamber (C) within the outer barrel (70) contains a piston (114) and flushing medium (M) displacable from the chamber (C) and into the core barrel during forceful displacement of the piston following actuation of the flushing device. Actuation of the flushing device is initiated by means (B) passed down the drill string into engagement with actuating means (94) allowing displacement of the piston and flushing medium from the chamber into the core barrel. Tripping means (112) are also disclosed responsive to the final movement of the piston to actuate, and seal the flushed pressure core barrel (10) and core sample (51) therein downhole.

Dependencies are inferred from the claim text.