(19)
(11) EP 0 155 128 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
16.04.1986 Bulletin 1986/16

(43) Date of publication A2:
18.09.1985 Bulletin 1985/38

(21) Application number: 85301428

(22) Date of filing: 01.03.1985
(84) Designated Contracting States:
DE FR GB NL

(30) Priority: 08.03.1984 US 587345

(71) Applicant: GEO VANN, INC.
 ()

(72) Inventors:
  • Colle, Edward A., Jr.
     ()
  • George, Flint Raymond
     ()
  • Yates, Donald N., Jr.
     ()

   


(54) Devices for actuating explosive charges in wellbores, and methods of perforating boreholes


(57) @ A device (10) for actuating an explosive charge downhole in a wellbore includes a combustive reaction initiator (30, 66, 100) actuated in response to a first pressure condition in a portion of the wellbore and an explosive charge actuator. A time delay device (136) is provided wherein a combustive reaction is initiated by the initiator and continues for a time delay period providing sufficient time for an operator to alter the first pressure condition to a second pressure condition at the time of explosive actuation. The delay device is operative at the end of the time delay period after initiation to actuate the explosive charge.






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