Patent ID: 6386111
Filing Date: 2002-05-14
Classification: E21B,F42D

Abstract:
A stemming arrangement for a blast hole having at least one explosive charge therein, the arrangement comprising:at least one rigid hollow member arranged in use in the blast hole outwardly of an associated explosive charge said hollow member having an undeformed curved shape such that it fits with clearance between opposed wall portions of the blast hole, said curved shape defining an internal space configured to contain a stemming material when used in the blast hole; and wherein detonation of the associated explosive charge deforms the hollow member from its undeformed position so as to substantially block the bore of the blast hole at the location of the hollow member to substantially impede outward passage of material past the hollow member, and the hollow member is made of sufficiently strong material to remain substantially functionally intact after detonation of the associated explosive charge.