Propellant for fracturing wells

• US 20060075890A1
• Filed: 10/13/2005
• Published: 04/13/2006
• Est. Priority Date: 10/13/2004
• Status: Abandoned Application

• Current Assignee: Propellant Fracturing & Stimulation, LLC
• Original Assignee: Propellant Fracturing & Stimulation, LLC
• Inventors: Tiernan, John P.
• Application Number:
  US11/249,667
• Publication Number:
  US 20060075890A1
• Time in Patent Office: Days
• US Class Current: 89/1.150
• CPC Class Codes: F42B 3/00 Blasting cartridges, i.e. case and explosive fuse cords, e.g. detonating fuse cords C06C5/00; chemical aspects of detonators, blasting caps or primers C06C7/00
• CPC Class Codes: F42B 3/10 Initiators therefor percussion fuzes F42C7/00; percussion caps F42C19/10; electric primers F42C19/12

Abstract

An apparatus for fracturing wells employs a propellant charge with a metallic foil to rapidly ignite the surface of the propellant charge. The assembly can be covered with an protective coating to protect against fluids in the well bore.

Claims

1. An apparatus for fracturing wells comprising:

a propellant charge for insertion into a well and having at least one surface;

a metallic foil adjacent to the surface of the propellant charge; and

an ignition element for igniting the metallic foil, and thereby rapidly igniting the surface of the propellant charge.

2. The apparatus of claim 1 further comprising a protective layer covering at least a portion of the propellant charge.

3. The apparatus of claim 2 wherein the protective layer comprises a fluoroelastomeric material.

4. The apparatus of claim 1 wherein the ignition element comprises a piece of propellant generating hot combustion gases to ignite the metallic foil.

5. The apparatus of claim 1 wherein the metallic foil comprises nickel and aluminum.

6. The apparatus of claim 1 wherein the metallic foil comprises nickel and palladium.

7. The apparatus of claim 1 wherein the metallic foil comprises nickel and zirconium.

8. The apparatus of claim 1 wherein the propellant charge is divided into a plurality of segments with interior surfaces between adjacent segments, and wherein the metallic foil is sandwiched between the interior surfaces.

9. The apparatus of claim 1 wherein the propellant charge has a substantially cylindrical exterior surface covered by the metallic foil.

10. An apparatus for fracturing wells comprising:

a propellant charge for insertion into a well, said propellant charge being divided longitudinally into a plurality of segments with interior surfaces between adjacent segments;

a metallic foil between the interior surfaces of the propellant charge; and

an ignition element for igniting the metallic foil, and thereby rapidly igniting the interior surfaces of the propellant charge.

11. The apparatus of claim 10 further comprising a protective layer covering at least a portion of the exterior of the propellant charge.

12. The apparatus of claim 11 wherein the protective layer comprises a fluoroelastomeric material.

13. The apparatus of claim 10 further comprising a longitudinal passageway extending from the ignition element along an interior surface of the propellant charge for propagation of combustion gases along length of the propellant charge.

14. The apparatus of claim 13 wherein ignition element comprises a dowel of propellant in the longitudinal passageway.

15. The apparatus of claim 10 wherein foil comprises nickel and aluminum.

16. An apparatus for fracturing wells comprising:

a propellant charge for insertion into a well and having an exterior surface;

a metallic foil covering the exterior surface of the surface of the propellant charge;

a protective layer covering the metallic foil and propellant charge; and

an ignition element for igniting the metallic foil, and thereby rapidly igniting the surface of the propellant charge.

17. The apparatus of claim 16 wherein the metallic foil comprises nickel and aluminum.

18. The apparatus of claim 16 wherein the protective layer comprises a fluoroelastomeric material.

19. The apparatus of claim 16 wherein the propellant charge further comprises a groove in the exterior surface of the propellant charge containing the ignition element.