Triple-base

Rocket Propellants. SoHd rocket propellants are mostly based on chemically cross-linked polymeric elastomers to provide the mechanical properties required in launchings and the environmental conditions experienced in storage, shipment, and handling (see Elastomers, synthetic). Double-and triple-based nitrocellulose propellants are also employed as rocket propellants. 

Continuous Solvent—Extrusion Process. A schematic for a typical continuous process, widely used for making solvent propellant for cannons, is shown in Figure 7. This continuous process produces ca 1100 metric tons of single-base propellant per month at the U.S. Army Ammunition Plant (Radford, Virginia). Continuous processes have also been developed for double- and triple-base propellants and for stick as well as granular geometries. A principal aspect of these processes has been the extensive use of single- and double-screw extmders instead of the presses used in the batch process. 

Triple-base propints use primarily NGu as a third major ingredient in addition to NC and NG. Typical compns are shown in Table 3. The major use of this type of proplnt is in gun proplnts for mortar and artillery shells... 

Current propellent explosives may be divided into three classes single base, double base and composite however double base propellants which contain picrite are often considered a separate class and called triple base. 

Triple base propellant. A propellant containing nitroglycerine, nitrocellulose and Picrite. 

Triple-based propellants are mixtures of nitroguanidine, nitrocellulose, and nitroglycerine. The mixture reduces the muzzle flash observed with double-based propellants, reduces the burn temperature, which protects the gun barrel, and increases the gas volume. Triple-based propellants are used in tank guns, large caliber guns, and some naval weapons. 

Figure 6.5 Triple base pair for the Tetrahymena ribozyme (PDB 1X8W). Visualized using CambridgeSoft Chem3D Ultra 10.0 with notations in ChemDraw Ultra 10.0. (Printed with permission of CambridgeSoft Corporation.)...

Nitroguanidine (NQ) is a nitramine compound containing one N-NOj group in its molecular structure. In contrast to cyclic nitramines such as HMX and RDX, its density is low and its heat of explosion is also comparatively low. However, the Mg of its combustion products is low because of the high mass fraction of hydrogen contained within the molecule. Incorporating NQ particles into a double-base propellant forms a composite propellant termed a triple-base propellant, as used in guns. 

Triple-base propellants are made by the addition of crystalUne nitroguanidine (NQ) to double-base propellants, similar to the way in which nitramine is added to CMDB propellants as described in the preceding section. Since NQ has a relatively high mole fraction of hydrogen within its molecular structure, the molecular mass of the combustion products becomes low even though the flame temperature is reduced. Table 4.13 shows the chemical composition, adiabatic flame temperature, and thermodynamic energy,/ as defined in Eq. (1.84), of a triple-base propellant at 10 MPa (NC 12.6% N). 

Fig. 4.26 Thermodynamic energies of singie-, doubie-, and triple-base propellants.

Figure 4.26 shows the thermodynamic energy,/ as defined in Eq. (1.84), of singlebase, double-base, and triple-base propellants as a function of the combustion temperature, Tg. Though the/values of double-base propellants are high, Tg is also high. In order to suppress gun erosion, Tg needs to be low. Triple-base propellants are thus formulated to reduce erosion while maximizing the /value. 

Single base" smokeless powder, developed mainly in the United States, uses only nitrocellulose. "Double base" smokeless powder, developed in Europe, is a blend of nitrocellulose and nitroglycerine. "Cordite," a British development, consists of 65% NC, 30% NG, and 5% mineral jelly. The mineral jelly (a hydrocarbon material) functions as a coolant and produces substantial amounts of CO 2, CO, and H 2O gas to improve the propellant characteristics. "Triple base" smokeless powder, containing nitroguanidine as a third component with nitroglycerine and nitrocellulose is also manufactured. 

Based on 1995 estimates, the cost for the removal of a hot spot with dimensions 40 ft by 60 ft by 10 ft deep with the grouting extending 10 ft beyond the hot spot was estimated at 3,295 million. These costs could double or triple based on the project management, the need for containment devices other than weather shields, health physics support, and sampling required during cleanup operations. No cost estimate is provided for treatment and final disposal (D13730E, pp. vi, 120). Details of the cost estimates are given in Table 3. 

Smokeless Propellant. Term used to distinguish the relatively smokeless single-base, double-base and triple-base propellants from BkPdr which produces heavy smoke (Ref 40a, p 133) (See also CANNON PROPELLANTS in Ref 44, p C29-R)... 

Triple-Base Propellant. See under Propellant in this Glossary... 

Length of complete round with fuze 34.15 inches, maximum muzzle velocity 1700-1800fps and max range 328 yds (300 meters). Its propellant chge consists of 3.1 lb of proplnt M30A1, which is a modification of triple-base proplnt M30 listed in Vol 2 of Encycl (Ref 48) p C34, Table V (Ref 52 and its Appendix, pp 2-112 2-113) Ammunition for 37-mm to 105-mm inclusive is either "fixed" or "semi-fixed (See Ref 43, p A385-L). Ammunition of larger caliber can be either "separated"(such as... 

Yes No Secondary high explosive. Found in triple-base smokeless powders o ... 

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