Smokeless powder heat tests

The majority of the stability tests for smokeless powder are much the same as the methods used to determine the stability of nitric esters, in particular nitrocellulose (Vol. II). They are based on heating samples of the powder, thus starting decomposition processes or hastening processes already initiated within the powder. The value of such methods is comparative, since at an elevated temperature different reactions occur than those which would arise under normal conditions of storage. Nevertheless experiments over many years have shown that certain interrelations may be established for the stability of powder at various temperatures. Vieille [61] reports that the heating of a sample of powder for 1 hr at a temperature of 110°C involves approximately the same decomposition as ... 

Heat test (Abel test). The oldest and the most popular qualitative test is the heat test introduced in Great Britain by Abel in 1865 [86]. It is called the Abel test on the Continent of Europe and the KI starch test in the U.S.A. It consists in warming a sample of nitroglycerine or nitrocellulose (or dynamite or smokeless powder) in a test tube in which a potassium iodide-starch paper moistened with aqueous glycerol solution is suspended (Fig. 1). Warming is carried out until the... 

Silvered Vessel test. The so-called Silvered Vessel test is a stability test that consists in determining the period of heating necessary to cause exothermic decomposition of the substance. It is usually limited to determining the stability of smokeless powder and is described in Vol. III. 

Brunswig s Test(Loss in Weight at 110°). A heat or stability test applicable to gelatinized smokeless powder... 

It if necessary to use pure water, as used for electric conductivity work, and to adhere to constant conditions of working. The method is frequently combined with a hearing trial. Thus liansen heated smokeless powders in the ground condition at no and tested samples at intervals pf an hour by means of the quinhydrone electrode to ascertain the rate of formarimodified method the powder is heated under water at 100 to bring about a hydrolytic decomposition. Grottanelli passes a slow current of air over a large sample (500 g.) of powder, which is maintained at 80 . and then into an absorption vessel in which the /H value is measured. Pariik also passes the (pues into water under modified ccalcium carbonate in powders has been examined by Mete. 

Mercury in Abel heat test, 77 in mercury fulminate, estimation of, 60 in smokeless powders, estimatioin of, 54 Mercury fulminate, analysis of mixtures containing, 15a explosive properties of, 153 mixture fur )ercu5sioa caps,... 

Skin glue, preparation of, 105 Slow matches, 156 Smokeless powder, analysis of, 49 determination of moisture in, 51 heat test for, 73 preparation of samples of, 49 qualitative analysts of, 50 quantitative analysis of, 30 Sodium chlorate, for use in explosives, examination of, 6... 

Horsley s Apparatus—Table of Firing Points—The Government Heat Test Apparatus, c., for Dynamites, Nitro-Glycerine, Nitro-Cotton, and Smokeless Powders—Guttmann s Heat Test—Liquefaction and Exudation Tests— Page s Regulator for Heat Test Apparatus—Specific Gravities of Explosives—Will s Test for Nitro-Cellulose-Table of Temperature of Detonation, Sensitiveness, c. 

Upon leaving the filter house, where it has been washed and filtered, and has satisfactorily passed the heat test, it is drawn off from the lowest tank in indiarubber buckets, and poured down the conduit leading to the precipitating house, where it is allowed to stand for a day, or sometimes longer, in order to allow the little water it still contains to rise to the surface. In order to accomplish this, it is sufficient to allow it to stand in covered-in tanks of a conical form, and about 3 or 4 feet high. In many works it is previously filtered through common salt, which of course absorbs the last traces of water. It is then of a pale yellow colour, and should be quite clear, and can be drawn off by means of a tap (of vulcanite), fixed at the bottom of the tanks, into rubber buckets, and is ready for use in the preparation of dynamite, or any of the various forms of gelatine compounds, smokeless powders, c., such as cordite, ballistite, and many others. 

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