Cowles Dissolver Fire Involving IR Flare Mix
Abstract
In November, 1993, a fire occurred in a Cowles Dissolver while mixing infrared decoy flare composition. The major constituents of the mix were magnesium, polytetra-fluoroethylene (PTFE), and a fluoroelastomer binder dissolved in acetone. Hexane is used to precipitate the binder and wash the mix. During the wash cycle, ignition occurred and consumed the mix. There were no injuries but significant heat damage was evident in the mixer bay. Deluge, blow-out walls and other safety features functioned as intended. A Board of Investigation composed of both Government and Contractor personnel was convened to determine the most probable cause. The Board concluded that the most probable cause for the fire was either ESD or friction. Subsequent efforts by Contractor personnel to quantify the electrostatic hazards of the system were not able to duplicate an ESD scenario. Field tests to evaluate the friction scenario were not completed. This paper will summarize the event and the subsequent testing to isolate the cause. The final conclusion was that, while ESD seems unlikely, it cannot be ruled out, nor can friction conclusively be proven to be the cause.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1994
- Accession Number
- ADA507122
Entities
People
- D. R. Dillehay
- R. C . Leander