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321 Universal Fire Detonator

321 Det

The 321 Bottom Fire Detonator is a resistorized electrical detonator developed to API RP-67 recommendations and employs a 51 Ohm resistor in the firing circuit. It is intended for use in hollow steel carrier and scalloped gun systems of all sizes where a fluid sensitive detonator will prevent the detonation of a flooded gun. Fluid migrating through the fluid holes in the body of the detonator will desensitize the powder around the resistor and prevent the detonator from achieving a high order detonation. The 321 Bottom Fire Detonator is specified for use in operating conditions of 350°F for 1 hour and compatible with a variety of detonating cords from 40gr/ft ribbon in thru tubing applications to 80 gr/ft XHV in high shot density applications.


Key Features:

  • Compact size ideal for small diameter guns and access ports
  • Det cord clip rotates freely to simplify the procedure of installing the detonator
  • Certified for use with 40 gr/ft ribbon cord and 80 gr/ft round cord without additional adapters
  • 99.99% reliability at 95% confidence level
  • Fluid Sensitive including for bottom fire applications
  • Temp rating of 350°F for 1 hour


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