IP Library Granted Patent US 8,136,439
Granted Patent B2
US 8,136,439 · App. 12/798,269 · Granted Mar 20, 2012

Explosive well tool firing head

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Quick Facts
Patent No.
US 8,136,439
App. No.
12/798,269
Granted
Mar 20, 2012
Kind
B2
Abstract

A firing head embodiment of the invention confines a connected capacitance cartridge, explosive detonator, and wireline connection switch within an independent, cylindrical housing tube that is environmentally capped at both ends by threaded closures for secure transport to a well site.

Claims (12)

1. An explosive well tool firing head comprising:

a housing tube having a bore therein between a first end and a second end;

first screw threads at said first end compatible with operating signal attachment means;

second screw threads proximate of said second end compatible with an explosive well tool means;

an operating signal contact means within said housing tube bore proximate of said first end for operatively receiving an operating signal;

detonator retainer means at said second end for securing the position and alignment of an electrically initiated explosive detonator to project axially beyond said second housing end;

a capacitive firing cartridge within said housing tube bore between said contact means and said detonator retainer means;

electrical continuity connections between said firing cartridge and said contact means; and,

electrically conductive leads from said firing cartridge to a detonator secured within said retainer means.

2. An explosive well tool firing head as described by claim 1 wherein a detonator is secured by said retainer means and connected by said electrically conductive leads to said firing cartridge.

3. An explosive well tool firing head as described by claim 2 wherein end closure caps are secured to said first and second screw threads to enclose said detonator and said housing bore.

4. An explosive well tool firing head as described by claim 3 wherein said second screw threads are positioned between said retainer means and said first screw threads.

Assignments (3)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 20, 2019
From: BELL, THOMAS VINCENT
To: W.T. BELL INTERNATIONAL, INC.
Reel/Frame 049234/0224 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 13, 2019
From: HAMMOND, SHARON LOUISE; BELL, ELAINE FAYE
To: W.T. BELL INTERNATIONAL, INC.
Reel/Frame 049162/0543 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 10, 2019
From: RAIRIGH, JAMES G.
To: W.T. BELL INTERNATIONAL, INC.
Reel/Frame 049144/0794 →
Continuity (4)
Continuation In Part 11442807 · May 30, 2006
Division 10762182 · Jan 21, 2004
Continuation 09949990 · Sep 10, 2001
Related Publication 20100212480A1 · Aug 26, 2010