Rapid deflagrating cord (RDC) ordnance transfer lines

• US 7,421,949 B2
• Filed: 03/05/2007
• Issued: 09/09/2008
• Est. Priority Date: 03/01/2002
• Status: Expired due to Term

• Current Assignee: McCormick Selph, Inc. (Fortive Corp.)
• Original Assignee: McCormick Selph, Inc. (Fortive Corp.)
• Inventors: Hilden, Lynn G.
• Primary Examiner(s): Bergin; James S
• Application Number:
  US11/713,702
• Publication Number:
  US 20070157842A1
• Time in Patent Office: 554 Days
• Field of Search: 102/275.1, 102/275.2, 102/275.3, 102/275.4, 102/275.5, 102/275.6, 102/275.7, 102/275.8, 102/275.9, 102/275.11, 102/275.12
• US Class Current: 102/275.1
• CPC Class Codes: C06C 5/04 Detonating fuses
• CPC Class Codes: C06C 5/06 Fuse igniting means; Fuse connectors

Abstract

A novel transfer ordnance line and novel end fittings for the transfer line for use in space vehicles, aircraft, missile systems and other military applications. The transfer line is a Rapid Deflagrating Cord (RDC) hermetically encapsulated in a metal tubing. The metal tubing terminates at end fittings such as a loaded high energy (HE) end fitting which detonates, a low energy (LE) end fitting which burns, and a percussion primer used to start burning of the RDC in the transfer line. The transfer line is constructed so that gases produced during the burning of the RDC do not escape and pose a threat to the surroundings during functioning and so moisture does not enter the system during shelf life, transportation, or at any other time prior to functioning. With minor adjustments to the transfer tube and the end fittings, the transfer tubing can be made flexible by forming a coil. With minor adjustments, a loaded HE end fitting can be made into a separation end fitting used ejected devices that must remain on course. Loaded HE end fittings may be placed in a manifold where it will ignite one or more loaded HE and LE end fittings to further progress the reaction. Loaded LE end fittings may be placed in transfer manifolds joining one or more other loaded LE end fittings to progress the reaction.

Claims

1. An ordnance energy transfer system, comprising:

a rapid deflagrating cord extending from a first end and a second end of a transfer line, said rapid deflagrating cord having a burn a rate of 1000 to 1500 feet per second; and

a first metal tubing hermetically encapsulating said rapid deflagrating cord from said first end to said second end of said transfer line, said first metal tubing being crimped at each end thereof, onto said transfer line at said first and second ends of said transfer line, to hold said rapid deflagration cord in place in said first metal tubing.

2. The system of claim 1, further comprising a first end fitting disposed at said first end of said transfer line, said first end fitting having a first ferrule being welded to said first metal tubing at said first end of said transfer line to form a hermetic seal for said rapid deflagrating cord and for charges stored in said first end fitting during shelf life, installation and use preventing unwanted moisture from entering the system and preventing gases produced from said system from escaping.

3. The system of claim 2, said first end fitting being one of a percussion primer end fitting, a detonating high energy end fitting and a low energy end fitting.

4. The system of claim 2, said first ferrule being surrounded and attached to an annular sealing material that provides a hermetic seal for said first end fitting and said rapid deflagrating cord when said first end fitting is installed inside a transfer manifold.

5. The system of claim 2, further comprising a second end fitting disposed at said second end of said transfer line, said second end fitting having a second ferrule connecting said second end of said transfer line to said second end fitting.

6. The system of claim 5, each respective ferrule being crimped to respective ends of said first metal tubing firmly pinching respective ends of said rapid deflagrating cord into respective ones of the first and second end fittings.

7. The system of claim 5, said second end fitting being one of a percussion primer end fitting, a detonating high energy end fitting and a low energy end fitting, when said first end fitting is the detonating high energy end fitting or the low energy end fitting.

8. The system of claim 5, said first end fitting being one of a percussion primer end fitting, a detonating high energy end fitting and a low energy end fitting, and said second end fitting being one of a detonating high energy end fitting and a low energy end fitting.

9. The system of claim 5, said first or second end fitting being a percussion primer end fitting comprising:

a ferrule having a crimped portion crimped at a first end of said ferrule over the crimped portion of said first metal tubing, an annular groove disposed at a second end of said ferrule, and an O-ring disposed in said annular groove;

a B-nut disposed over said first end of said ferrule for firmly holding said ferrule in place on said first metal tubing;

a percussion primer disposed in a compartment in said second end of said ferrule; and

a closure disk disposed over said percussion primer and closing said compartment, said closure disk being formed of stainless steel of sufficient thickness to permit said percussion primer to ignite when said closure disk is struck by a firing pin.

10. The system of claim 9, further comprising a plastic cap removably disposed over said closure disk, said second end of said ferrule and a threaded portion of said B-nut, said plastic cap serving to protect the percussion primer end fitting during shelf life and during transportation, said plastic cap being removed to permit said threaded portion of said B-nut to be threaded into a transfer manifold to enable said percussion primer to be ignited.

11. The system of claim 10, said O-ring being made of silicone rubber and forms a hermetic seal between said ferrule and said transfer manifold.

12. The system of claim 5, said first or second end fitting being a low energy deflagrating end fitting comprising:

a ferrule having a crimped portion crimped at a first end of said ferrule over the crimped portion of said first metal tubing, an annular groove disposed at a second end of said ferrule, said second end of said ferrule having predetermined slanted portion, wherein said annular groove is formed in said predetermined slanted portion of said second end of said ferrule, and an O-ring disposed in said annular groove;

a low energy booster charge disposed in a void formed along a central axis of said second end portion of said ferrule;

a spit hole formed along a central axis of a middle portion of said ferrule and separating said rapid deflagrating cord from said low energy booster charge;

a closure cup fitted into said void for closing said void, said closure cup having a rim welded to said second end of said ferrule; and

a B-nut disposed over part of said first end of said ferrule, for firmly holding said ferrule in place on said first metal tubing, and over said middle portion and a part of said second end of said ferrule.

13. The system of claim 12, further comprising an end cap removably disposed over said closure cup, said second end of said ferrule and a threaded portion of said B-nut, said end cap serving to protect the low energy deflagrating end fitting during shelf life and during transportation, said end cap being removed to permit said threaded portion of said B-nut to be threaded into a transfer manifold.

14. The system of claim 5, said first or second end fitting being a detonating high energy end fitting comprising:

a ferrule having a crimped portion crimped at a first end of said ferrule over the crimped portion of said first metal tubing, an annular groove disposed around a middle portion of said ferrule, and an O-ring disposed in said annular groove;

a special silicone rubber seal annularly disposed around a first portion of a second end of said ferrule;

a stainless steel interface retainer having an annular shape and disposed around a second portion of said second end of said ferrule between said O-ring and said special silicone rubber seal, a rim of the stainless steel interface retainer being welded to the ferrule;

a closure cup having a rim welded to an outside annular surface of said ferrule directly underneath said stainless steel retainer;

a high energy detonation charge and a lead azide booster charge disposed said closure cup, said lead azide booster charge being disposed between said second end portion of said ferrule and said high energy detonation charge;

a spit hole formed along a central axis of said second end of said ferrule and separating said rapid deflagrating cord from said lead azide booster charge; and

a B-nut disposed over part of said first end of said ferrule, for firmly holding said ferrule in place on said first metal tubing, and over said middle portion, a part of said second end of said ferrule and part of said stainless steel interface retainer.

15. The system of claim 14, further comprising an end cap removably disposed over said closure cup, said second end of said ferrule and a threaded portion of said B-nut, said end cap serving to protect the detonating high energy end fitting during shelf life and during transportation, said end cap being removed to permit said threaded portion of said B-nut to be threaded into a transfer manifold.

16. The system of claim 15, with said first metal tube comprising an aluminum tube, and a semi-flexible stainless steel tube centrally disposed over said aluminum tube, said stainless steel tube being shorter in length than said aluminum tube, each end portion of said stainless steel tube being crimped onto said aluminum tube, an inner surface area of a non-crimped portion of said stainless steel tube being separated from said aluminum tube.

17. The system of claim 2, said first ferrule having a booster charge stored therein, said first ferrule being laser beam welded to a rim of a first closure cup, said first closure cup facing away from said booster charge, said laser beam welding allowing stainless steel from said first closure cup and said first ferrule to mix and to serve as a donor of steel to said laser beam weld providing a strong attachment between said first closure cup and said first ferrule.

18. The system of claim 17, a bottom surface of said first closure cup being coined wherein portions of said bottom surface have a thickness less than 0.0025 inches where other portions of said bottom surface having a thickness of at least 0.003 inches.

19. The system of claim 17, said first ferrule having a spit hole along a central axis thereof, said spit hole being bounded on a first side by said rapid deflagrating cord and being bounded on a second side by a booster charge, said spit hole enabling and end of said rapid deflagrating cord to energize said booster charge to blow apart said first closure cup or to allow said booster charge to start the burning of said rapid deflagrating cord.

20. The system of claim 1, said first metal tubing having an inner diameter of 0.062 inches and an outer diameter of 0.094 inches allowing said first metal tubing to be semi flexible.

21. The system of claim 1, said rapid deflagrating cord having a diameter of 0.050 inches.

22. The system of claim 1, said rapid deflagrating cord comprising:

a rapid deflagration material of Cs₂B₁₂H₁₂ mixed with KNO₃; and

a metal encasement surrounding said rapid deflagration material, said metal encasement having a diameter of 0.050 inches.

23. The system of claim 1, with said first metal tube comprising an aluminum tube, and a semi-flexible stainless steel tube centrally disposed over said aluminum tube, said stainless steel tube being shorter in length than said aluminum tube, each end portion of said stainless steel tube being crimped onto said aluminum tube, an inner surface area of a non-crimped portion of said stainless steel tube being separated from said aluminum tube.