Difference between revisions of "Cordite"
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==History== | ==History== | ||
| + | Quoted herewith is a description of cordite manufacture from 1902: | ||
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| + | <blockquote>Nitro-glycerine, in the proper proportion, is poured on to dry gun-cotton, [nitrocellulose] to which no alkali has been added, and the two are mixed by hand.<br><br>In this condition it is known as cordite paste.<br><br>The paste is placed in an incorporating machine, some acetone being first poured in. The machine is started, and the remainder of the acetone is added. After kneading for hours, the mineral jelly is added, and the kneading continued for a further period of 3½ hours. The mixture, in the condition of a plastic dough, is then placed in cylindrical moulds. The mould is inserted in a press, and the cordite is forced through a die with one or more holes. The cordite comes through the die in long cords, and is cut to length and placed in trays or wound on reels. The cordite is then stoved, at a temperature of about 100° F., from 3 to 14 days, the time varying with the size. This operation drives off the acetone or any moisture, the cordite becomes tougher, and its diameter decreases. Cordite is then blended.<br><br>All lots of cordite from each manufacturer have consecutive numbers, irrespective of size, and one or more initial letters to identify the manufacturer, except Waltham Abbey cordite, which has only the lot number. Finished cordite resembles a cord of gutta percha, and its colour varies from light to dark brown. It should not look black or shrivelled, and should always possess sufficient elasticity to return to its original form after slight bending.<ref>''Treatise on Ammunition''. pp. 20-21.</ref></blockquote> | ||
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Revision as of 12:40, 23 March 2011
Cordite was a solid propellant used in various grades by the Royal Navy from 1889, replacing brown powder propellant. It has received a somewhat poor reputation, being widely held responsible for the loss of a number of warships owing to catastrophic magazine explosions.
History
Quoted herewith is a description of cordite manufacture from 1902:
Nitro-glycerine, in the proper proportion, is poured on to dry gun-cotton, [nitrocellulose] to which no alkali has been added, and the two are mixed by hand.
In this condition it is known as cordite paste.
The paste is placed in an incorporating machine, some acetone being first poured in. The machine is started, and the remainder of the acetone is added. After kneading for hours, the mineral jelly is added, and the kneading continued for a further period of 3½ hours. The mixture, in the condition of a plastic dough, is then placed in cylindrical moulds. The mould is inserted in a press, and the cordite is forced through a die with one or more holes. The cordite comes through the die in long cords, and is cut to length and placed in trays or wound on reels. The cordite is then stoved, at a temperature of about 100° F., from 3 to 14 days, the time varying with the size. This operation drives off the acetone or any moisture, the cordite becomes tougher, and its diameter decreases. Cordite is then blended.
All lots of cordite from each manufacturer have consecutive numbers, irrespective of size, and one or more initial letters to identify the manufacturer, except Waltham Abbey cordite, which has only the lot number. Finished cordite resembles a cord of gutta percha, and its colour varies from light to dark brown. It should not look black or shrivelled, and should always possess sufficient elasticity to return to its original form after slight bending.[1]
| Composition of Cordite Mark I[2] | ||
| Ingredient. | Percentage. | |
| Nitroglycerin | 58% | |
| Nitrocellulose (Nitrogen) |
37% (13.1%) | |
| Petroleum Jelly | 5% | |
| Composition of Cordite MD[3] | ||
| Ingredient. | Percentage. | |
| Nitroglycerin | 30% | |
| Nitrocellulose (Nitrogen) |
65% (Average 13.1%) | |
| Petroleum Jelly | 5% | |
Cordite Mark I began to be manufactured in 1889. It was first distributed to the Fleet in 1893 as propellant for 6-inch, 4.7-inch, 6-pdr, and 3-pdr Q.F. guns.[4]
With Cordite MD, first delivered in 1901, the calories per gram on burning (water as liquid) were reduced from 1,270 to 1,020.[5]
Footnotes
Bibliography
