Solventless double base propellant

Solventless Extrusion Process. The solvendess process for making double-base propellants has been used ia the United States primarily for the manufacture of rocket propellant grains having web thickness from ca 1.35 to 15 cm and for thin-sheet mortar (M8) propellant. The process offers such advantages as minimal dimensional changes after extmsion, the elimination of the drying process, and better long-term baUistic uniformity because there is no loss of volatile solvent. The composition and properties of typical double-base solvent extmded rocket and mortar propellant are Hsted ia Table... 

For civilian aircraft the facility for rapid starting is not important and cartridge operation is not often employed, particularly because it involves storing and handling explosives, even though the hazards of these explosives are those of fire and not of detonation. For military purposes, however, particularly for fighter aircraft which are best scattered on an airfield, a rapid start is of considerable importance. Therefore cartridge operated starters are much used for these aeroplanes. In Britain, development has been essentially with propellants based on ballistite, namely double base propellants of the solventless type, whereas in the United States composite propellants based on ammonium nitrate have proved more popular. 

Solventless double base propellant. A double base propellant in which gelatinisation is effected by mechanical means without the addition of solvent. 

Inhibiting Double Base Rocket Propellants at Picatinny Arsenal. Most of the work at Pica-tinny Arsn in connection with inhibiting of solventless extruded or cast double-base propellant has been with convolute wrappings of grains or tubes with cellulose acetate. There has been a trend toward use of extruded tubes made by the casting process... 

CSC. A British double-base propellant called Cordite Solventless Carbamite. See Cordite SC under CORDITE... 

Drying of Solventless Double-Base Propellants. Since the manuf of solventless double-base proplnts is potentially hazardous, particularly rolling, drying, extruding machine operations, all such opns are performed by remote control. Following the final mixing, wringing screen opns, the water-wet paste is preheated to 90°F and fed by remote control into differential rollers in sufficient quantity to make two sheets. Hot water or steam is used to control... 

P.R. Mosher, Solventless Double Base Propellants for Plasticizing MTN Nitrocellulose Propellants Without Use of Solvents , USP 4082583 (1978) CA 89, 45945 (1978)... 

Table 8. Composition and Properties of Double-Base Solventless Propellant...

Manufacture and Loading of Castable Solid Propellants , ORDM 7-230 (I960) 6)Ibid, Safety Requirements for Manufacturing Double-Base Solventless Propellants , ORDM 7-227 (I960) 7)Urbanski, Chemistry and Technology of Ejq>Iosives , Vol 2 (1965), 406... 

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