SIGNAL TRANSMISSION TUBE WITH INVERSE INITIATION RETENTION SEAL METHOD

• US 20150107476A1
• Filed: 07/25/2012
• Published: 04/23/2015
• Est. Priority Date: 10/14/2011
• Status: Active Grant

• Current Assignee: Famesa Explosives SAC
• Original Assignee: Famesa Explosives SAC
• Inventors: Perez Cordova, Pio Francisco, Palomind Cahuana, Jose William
• Granted Patent: US 9,310,174 B2
• Time in Patent Office: Days
• US Class Current: 102/200
• CPC Class Codes: C06C 5/04 Detonating fuses
• CPC Class Codes: F42B 3/087 Flexible or deformable blasting cartridges, e.g. bags or hoses for slurriesloaded cartridge bags F42B5/38
• CPC Class Codes: F42D 1/04 Arrangements for ignition ignition systems for shaped charge perforators E21B43/1185; ignition devices for seismic energy generators G01V1/06
• CPC Class Codes: F42D 1/043 Connectors for detonating cords and ignition tubes, e.g. Nonel tubes mounting of detonators in blasting cartridges F42B3/26

Abstract

A non-electric detonator connected to similar detonators with capsule 2 with having charge 8 and delay train 9. A tube 3 for transmitting a shock wave having an internal surface with a predetermined amount of a propagating explosive has one end mounted within capsule 2 adjacent to delay train 9. A seal 12 formed by collapsing a portion of tube 3 at a distance from its end prevents a shock wave accidentally created at capsule 2 from propagating to the rest of tube 3. Yet, the propagation of the wave is not prevented when it comes from the other end of tube 3. The distance from end 13a where seal 12 is formed needs to be selected for a predetermined explosive amount not sufficient to propagate the wave from capsule 2 but enough to propagate it when the wave comes from the other end.

Claims

1. A detonator device of the non-electric type comprising:

A. a detonator capsule 2 having a tubular elongated shape with an open end 13 and a closed end 13a and further including a first explosive charge 8 within said capsule 2, adjacent to said closed end 13a and at least one pyrotechnic delay train charge 9 adjacent to said explosive charge 8;

B. a tube 3 for transmitting a shock wave signal having an internal continuous channel and an internal surface 3a with a predetermined amount of a second explosive composition impregnated thereon to effectively propagate said wave without destroying said tube, and said tube including first and second ends, said first end connected to at least one detonator of the non-electric type and a first predetermined portion of said tube 3 adjacent to said second end being housed within said capsule 2 with said second end in abutting contact with said at least one delay train charge 9 and a seal 12 for interrupting the continuous communication of the internal channel and preventing the transmission of an inverse shock wave in said tube 3 and said seal 12 being located at a second predetermined distance from said second end defining a second predetermined portion of said tube 3, said seal 12 defined by an expandable collapsed third predetermined portion of said internal surface adjacent to said second predetermined portion thereby reducing the communication through said tube 3, and the amount of said second explosive in said second predetermined portion being insufficient to propagate said shock wave from said second end to said first end while permitting the propagation of said wave form from said first end to said second end when ignited; and

C. means for sealing said capsule 2 at a third predetermined distance from said open end.

2. The detonator device set forth in claim 1 wherein said seal is located between zero and three times the diameter of said tube away from said second end.

3. The detonator set forth in claim 2 wherein said seal provides a thickness of no less than 0.1 times the external diameter of tube 3 and no more than 0.7 times the external diameter of tube 3.

4. A method for detonating charges that comprises the steps of:

A) connecting at least two detonator of the non-electric type to a shock tube with two ends and an internal channel extending from one end to the other end to transmit a wave signal to activate said detonators through said internal channel; and

B) flattening a portion of said tube to define a seal at a predetermined distance from the ends of the tube connected to said at least two detonators so that the diameter of said internal channel if reduced by predetermined amount.

5. The method set forth in claim 4 wherein said predetermined distance varies from zero to three times the outer diameter of said tube 3.

6. The method set forth in claim 5 wherein said seal provides a thickness of no less than 0.1 times the external diameter of tube 3 and no more than 0.7 times the external diameter of tube 3.