Stemming arrangement and method for blast holes
AssigneeAdvanced Blasting Technology, Inc.
InventorPeter Christian Shann
Life of this patent
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Abstract
The present invention relates to a stemming arrangement and stemming method for use in blast holes. A rigid but deformable hollow member is located in a blast hole with its curved shape providing a clearance between opposed wall portions. A stemming material is contained within the curved portion. Detonation of the explosive deforms the hollow member outwardly into contact with the opposed wall portions of the blast hole.
Claims20
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.
A method of stemming a blast hole having at least one explosive charge therein, the method comprising:
- locating at least one rigid hollow member 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
- detonating the associated explosive charge so as to generate an explosive force moving outwardly of the blast hole and with the major portion of the force impacting initially substantially centrally of said undeformed hollow member so as to deform the hollow member outwardly into contact with the opposed wall portions of the blast hole so as substantially to block the bore of the blast hole at the location of the hollow member and substantially impede outward passage of material past said member, and the hollow member being made of sufficiently strong material to remain substantially functionally intact after detonation of the associated explosive charge and thereby contain the explosive charge within the blast hole inwardly of the hollow member.
Dependencies are inferred from the claim text.