Wireline Core Barrels

It is used to recover core samples efficiently, because the inner tube is pulled out by an overshot on a wireline cable.

Double-tube systems are commonly used in stable ground. Triple-tube systems are used to improve core recovery in soft or broken formations.

Core lifter, core lifter case, stop ring, and inner tube liner are typically stocked, because wear and recovery issues are managed there.

Higher outer-tube stiffness is promoted to help control deviation. Gains of ~40% (standard) to ~70% (full-hole) have been claimed.