Conical plug for sealing blastholes in open cut mining

摘要

A conical plug for sealing a blast hole in the earth is provided. The plug is made from a generally circular sheet of elastic material such as plastic or metal and can be folded and releasably locked with a trigger into a conical shape. When in its conical shape, the plug is lowered into a blast hole and, when in position, a release weight is slid down the lowering cable to impact and release the trigger. When the trigger is released, the plug expands and is wedged against the sides of the blast hole forming a plug capable of supporting debris in the upper portion of the blast hole.