1. n. [Formation Evaluation]
A piece of steel cable placed inside a logging head that is designed to break at a predetermined tension. If the logging tool becomes stuck in the borehole, there is a danger that the logging cable will break at surface, since this is the place of maximum tension. It is difficult to fish a long length of tangled cable in the borehole. The weak point is designed to break before the cable, so that the latter can be retrieved, leaving only the logging tool and head in the borehole.
