Propellants, Single-Base, Manufacture

Very little cair be added to the description in Vo . Ill, pp. 571 641 rnij pp. 663 664 oir the methods of manufacture t)l single base propellants. 

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. 

Manufacture of Double-Base Propellants. The following methods are used a)Solvent Process -similar to that used for single-base proplnts,... 

Nitrocellulose, which is the most important component of single-base and double-base powders and multibase rocket propellants. It is also used to gelatinize commercial explosives. Outside the explosives industry, it is also used in the manufacture of lacquers and varnishes ... 

Use af Ethanol and Ether in the Manufacture af Single-Base Smokeless Propellant s. Operation s in manuf of single-base smokeless proplnts from Pyrocellulose, which is NC of N content 12.60-0.10% (described in Vol 2 of Encycl, p 003) are discussed in Vol 3 of Encycl, under "Colloiding Agents and Colloidal Propellants on pp C398 C399. Manuf of NC is described in Vol 2, p 002, while its stabilization for use in smokeless propellants is described in Vol 2, p 007... 

Refs DMarshall 3 (1932), 89 2)Anon, Mili-tary Explosives , War Dept Tech Manual TM 9 2900 (1940), 26-32 3)US Ord Corps Manual, Safety Requirements for Manufacturing Small Arms Ammunition , ORDM 7 228 (1955) 4)Ihid, Safety Requirements for the Manufacture of Single-Base Solid Propellants , ORDM 7-229 (1959) 5)R>id, Safety Requirements for the... 

Military. The single-component explosives most commonly used for military compositions are TNT, RDX or HMX, nitrocellulose, and nitroglycerin. The last two are used almost exclusively to make propellants. The production volume of TNT far exceeds that of any other explosive. It is used as manufactured, as a base of biaary slurries with other high melting explosives, or ia ternary systems generally containing a biaary mix and aluminum. 

Any distinction between cordite and ballistite which is based upon the methods by which the materials are manufactured is now no longer valid. Certain cordites are made without the use of a volatile solvent. Ballistites are made from soluble and from insoluble nitrocellulose, with and without the use of acetone, ethyl acetate, or other volatile solvent. Cordite is the name of the propellant which is used by the British armed forces. Ballistite, generally in flakes, sometimes in cords and in single-perforated tubes, is the preferred military powder of Italy, Germany, and the Scandinavian countries. 

The approach to use multiple components is based on the Level 2 Prometheus Requirement to meet the NASA Single Point Failure Policy. NASA experience indicates the prudence of having redundant components, even if they have demonstrated reliability, to ensure that manufacturing defects, human error, or an unexpected event does not lead to a mission ending failure. This is also consistent with NRPCT practice. For those components where redundancy is considered impractical, exceptions to the single point failure avoidance requirement is provided. For the currently envisioned Prometheus spacecraft, the reactor, the reactor coolant loop, the boom, and the xenon propellant tank all require such exceptions. 

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