Apparatus and method for producing fragment-free openings

A method of making a fragment-free opening in a barrier, comprising:

• a) securing an explosive to a buffer material;
• b) securing the buffer material to the barrier;
• c) setting off the explosive and creating an explosive force;
• and
• d) creating an opening in the barrier by failing the barrier along intersecting lines of failure with the explosive force into a plurality of petals that remain attached to the barrier after displacement to define the opening.

A method of forming a fragment-free opening in a barrier, comprising:

• a) initiating an explosive material mounted on the barrier and creating shock pressure;
• b) creating at least two intersecting fracture plane in the barrier with the shock pressure;
• and
• c) propagating fractures in the barrier along the intersecting fracture planes to form a plurality of cantilevered petals defining an opening in the barrier.

An apparatus for creating a fragment-free opening in a barrier, comprising:

• a) an explosive charge;
• b) shock attenuating material encapsulating all but one surface of the explosive charge;
• c) a buffer material mounted on the one surface of the explosive charge not encapsulated with shock attenuating material;
• d) adhesive means with the buffer material for mounting the apparatus on the barrier;
• e) means for setting off the explosive charge and creating an explosive force, wherein the explosive force creates intersecting lines of failure in the barrier whereby the barrier fails from an initial point and along the intersecting failure lines thus forming petals cantilevered from the barrier and defining an opening therein.

An explosive apparatus for creating a fragment-free opening in a barrier, comprising:

• a) a shock absorbent;
• b) an explosive material mounted with the shock absorbent;
• c) a shock buffer mounted with the explosive material having an adhesive surface adapted for attaching the apparatus to the barrier such that the shock buffer is interposed between the explosive material and the barrier;
• and
• d) a detonator mounted in the shock absorbent and configured so as to set off the explosive material at at least three locations wherein intersecting planes of fracture are created in the barrier by the shock pressure from the detonated explosive material thus forming petals cantilevered from the barrier and defining an opening therein.