A core-gripping device consisting of a series of three or more serrated-face,
tapered wedges contained in slotted and tapered recesses cut into the inner
surface of a lifter case or sleeve. The case is threaded to the inner tube of a
core barrel. As the core enters the inner tube, it lifts the wedges up along
the case taper. When the barrel is raised, the wedges are pulled tight,
gripping the core. Long
Source:
Dictionary of Mining, Mineral, and Related Terms
