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Old February 5, 2013, 11:18 AM   #12
Slamfire
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Join Date: May 27, 2007
Posts: 4,076
This came from the Propellant Management Guide Dec 2003 version.


These guys are primarily concerned with keeping ammunition depots from blowing up.

But, the same nitrocellulose (single base) and the same nitrocellulose and nitroglycerine (double base) that you use, they use in many things.

Just take a look at all auto ignition incidents you never heard about till now: (and they are only Army!)


1-4. BACKGROUND

a. Propellants and propelling charges that we store, transport and maintain warrant our special attention. Among commonly stored energetic materials, only nitrate ester-based propellants (principally nitrocellulose-based ones) have the propensity to spontaneously combust (self-ignite, autoignite) without warning while sitting in storage; catastrophic losses can result. Artillery and Small Arms propellants are perhaps the most dangerous materials that Army installations routinely handle and store. Propellant can be unpredictable, decomposing into an unstable condition within four or five years of manufacture. Inadequate propellant safety programs have contributed to several self-ignition incidents at military and commercial installations in the United States and abroad.

b. When grains, flakes, sticks or sheets of propellant inside a container ignite, sufficient heat and flame is produced to ignite the remaining propellant material in that container. If unstable propellant is present in even minimal quantities (e.g., a single container), it might combust and could lead to ignition of the entire contents of the storage structure. Propellant burns at a very rapid rate in a process that is known as deflagration. Deflagration differs significantly from detonation in that deflagration involves very rapid combustion that takes place on the surface of the propellant. Detonation, on the other hand, occurs due to a different process that involves a shock wave moving at supersonic speeds through the explosive material, thereby causing its nearly immediate decomposition. Simply put, deflagration operates on the basis of heat transfer, while detonation operates on the basis of a shock wave.

c. During the period 1984 through 1997, seven propellant autoignition events occurred at U.S. Army Materiel Command (AMC) installations.

1. 1984: Lake City AAP
IMR powder that was only 5 years old autoignited and the above ground magazine & its contents were destroyed. More than 100,000 lbs of powder deflagrated.

2. 1984: Lake City AAP
The same lot of IMR powder, a fragment quantity isolated and saved for critical production testing, autoignited two months after the previous fire. Only a small quantity of powder was lost, but another magazine was destroyed.

3. 1985: Blue Grass Army Depot
The local-stocks storage magazine use for demilitarization activities contained high explosives material as well as unmonitored M10 propellant powder. Autoignition of the powder and its resulting deflagration gradually ignited the other energetic materials present. The earth covered magazine and its contents were destroyed.

4. 1987: Lone Star AAP
Benite was stored in a heated magazine so that it could be temperature conditioned prior to loading into production items. The building became overheated which accelerated the rate of decomposition of the benite to a point that autoignition occurred. The structure and contents were lost.

5. 1989: Hawthorne Army Depot
8-inch, 55-caliber propelling charges loaded with single-base propellant autoignited in an earth-covered magazine more than one year after the Navy ordered the lot destroyed due to low stability. The magazine contents of 30,715 lbs of various propellants were destroyed, and the magazine was heavily damaged.

6. 1996: Red River Army Depot
Expulsion charge assemblies for large caliber artillery rounds, each charge filled with only one ounce of M10 propellant and stored 250 to a box, autoignited. The earth-covered magazine and its contents were totally destroyed.

7. 1997: Hawthorne Army Depot
M9 flake propellant bags that had been removed from 81MM mortar rounds were bulk-packed and placed into long-term storage. A container of unstable propellant autoignited, and all 20,000 lbs of propellant inside the earth-covered magazine were destroyed. The magazine was severely damaged. Value of contents lost was more than $3,000,000, while the cost to repair the magazine was $164,000.
d. Accidental autoignition of propellant occurs at other than Army facilities, too. During the same time period as the incidents above, propellant self-ignition accidents have occurred at Navy facilities and at privately owned industrial storage sites. If you consider the number of accidents versus the limited number of locations that store artillery and small arms propellants, you begin to realize that the chances of having an accident happen at your installation are not as unlikely as you may have imagined.


At first I thought SAAMI powder storage recommendations as to quantity and containers were alarmist or just off the wall, but with enough education, I can see their concerns.
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