Method and apparatus for safe transport handling arming and firing of

Abstract

An exploding foil bubble activated detonator, adapted for use in a perforating gun, includes an exploding foil, the exploding foil including as neck section which vaporizes when a current of sufficient magnitude and duration flows therethrough, a layer of polyimide material deposited over said foil, and a spacer layer deposited over said layer of polyimide material, the spacer layer including a guiding hole disposed directly over the neck section of the foil. When the current flows through the neck section of the foil, a turbulence is caused to occur directly above the neck section. This turbulence causes a portion of the polyimide material to expand to form a bubble. The bubble is shaped and sized by the guiding hole in the spacer layer which is disposed directly over the neck section of the foil. The shaped and sized bubble in the polyimide material impacts an explosive thereby detonating the explosive. A selective gun firing system may include the bubble activated detonator and functions to allow an operator to selectively fire, in a predetermined sequence, a plurality of perforators in the perforating gun, such as from bottom gun to top gun. A hall effect sensor disposed in a well truck is connected to a wireline to which the perforating gun is connected and senses a current in the wireline. A novel safety barrier is inserted into a hole in a barrel of a prior art exploding foil initiator (EFI) detonator for blocking a flying plate flying in the hole and thereby preventing accidental detonations of the EFI detonator.