HWL HWL-U HWL-3 wireline drilling core barrel single double and triple tube core barrels
HQ BQ NQ PQ BQU NQU HQU NQ3 HQ3 PQ3
Using a wireline system, core is recovered quickly by retrieving the inner tube directly through the drill string. The rods remain in the hole until the bit needs to be replaced. This has big cost advantages when drilling deep holes for mineral exploration.