EP0001526A1 - Process for the removal in a liquid water/alcohol medium of solvents present in granular powder propellants - Google Patents
Process for the removal in a liquid water/alcohol medium of solvents present in granular powder propellants Download PDFInfo
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- EP0001526A1 EP0001526A1 EP78400114A EP78400114A EP0001526A1 EP 0001526 A1 EP0001526 A1 EP 0001526A1 EP 78400114 A EP78400114 A EP 78400114A EP 78400114 A EP78400114 A EP 78400114A EP 0001526 A1 EP0001526 A1 EP 0001526A1
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- C—CHEMISTRY; METALLURGY
- C06—EXPLOSIVES; MATCHES
- C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
- C06B21/00—Apparatus or methods for working-up explosives, e.g. forming, cutting, drying
- C06B21/0091—Elimination of undesirable or temporary components of an intermediate or finished product, e.g. making porous or low density products, purifying, stabilising, drying; Deactivating; Reclaiming
Definitions
- the present invention relates to a method for removing the solvents contained in the propellant powders in grains manufactured according to the so-called "solvent" method, when said solvents consist of an ether-alcohol mixture.
- grain powders are understood to mean both powders in the form of cylindrical grains and those in the form of strips or flakes.
- the propellant powders in grains manufactured according to the so-called "solvent" process are generally either powders with a simple nitrocellulose base, or powders of which at least a part of the energetic material consists of nitrocellulose, the remainder of the energetic material consisting of solid organic propellant bases well known to those skilled in the art, such as, for example, polyvinyl nitrate, cellulose acetate, polyvinyl acetate, etc. or mixtures of these bodies.
- the conventional spinning operation at room temperature or slightly above room temperature has a major drawback: the partial pressures of ether and alcohol being close to this temperature range, the two solvents evaporate at the same time time.
- the molecules contained on the surface of a grain evaporate more easily than those contained in the heart of the grain.
- the evaporation of the ether can cause condensation of the water on the surface of the grain, which leads to a reprecipitation of the nitrocellulose on the surface, so a film forms on the surface of the powder grain. makes the diffusion of the solvents contained in the core of the powder grain more difficult. It is this phenomenon which explains the necessity of the long duration of the so-called soaking operation, the durations of which, in hot water, are in many cases close to 150 hours.
- the object of the present invention is to remedy the aforementioned drawbacks by proposing a new process for eliminating the solvents contained in the grains of propellant powders produced according to a process with solvents in which said solvents are constituted by the mixture of an ether and of '' an alcohol, a process which ensures the elimination of ether so as to avoid any film formation on the surface of the powder grains and to allow a reduction of the soaking time and consequently an increase in the chemical stability of the powder by less degradation of the latter.
- this result is achieved by performing a selective elimination of the ether contained in the powder grains by immersion of the latter in a hydroalcoholic liquid medium in which a gas is bubbled.
- the process for removing solvents according to the invention thus has the direct consequence of reducing the duration of the subsequent soaking and, as an indirect consequence, a gain in the chemical stability of the powder grain, as well as better reproducibility of the powder thanks to the the fact that the solvent removal conditions can be repeated almost identically.
- the method according to the invention also allows a reduction in the intermediate handling that a conventional soaking required.
- the ether contained in the powder grains produced according to the so-called solvent process is removed, the said solvents being constituted by the mixture of an alkanol and an ether of alkyl, by immersion of said grains of powders in a hydroalcoholic liquid phase in which a gas circulates, said hydroalcoholic phase being constituted by an aqueous dilution of the alkanol used as solvent for said powder, in proportions such that said title hydroalcoholic liquid phase between 20 and 70 degrees Gay-Lussac, the temperature of said hydroalcoholic phase being between 10 and 40 ° C.
- Said gas can simply be air or an inert gas which is a good carrier of said ether, such as nitrogen. It may be advantageous, in the case of large installations in order to eliminate any risk of detonation, to start the elimination of the ether using such an inert gas and to finish said elimination either with said inert gas, more simply with air.
- the ratio of the mass of powder to be treated to the mass of the hydroalcoholic liquid phase to be used must be less than or equal to one and preferably close to 1/3.
- the hydroalcoholic liquid phase must titrate between 20 and 70 degrees Gay-Lussac and preferably between 30 and 50 degrees Gay-Lussac, its temperature must be between 10 and 40 ° C and preferably between 15 and 25 ° C.
- any apparatus can be used to ensure the circulation of a gas in a liquid phase such as for example a reactor provided with one or more inlets for the gas which must circulate in the liquid phase.
- the apparatus is equipped with an agitator such as for example an anchor or propeller agitator.
- said apparatus is surrounded by a thermostatically controlled enclosure so as to be able to properly control the temperature in the implementation of the method according to the invention.
- the grains of powders can either be subjected to short-term soaking and be smoothed and / or graphitized according to conventional techniques or else be subjected to smoothing-soaking in an aqueous liquid medium as described in the French patent application. n ° 77.11938 in the name of the plaintiff with possibly a later graphitization.
- powder B 19 T is a simple nitrocellulose base powder, in the form of small cylinders 3 mm in diameter and 4 mm long axially drilled with 19 holes.
- the composition of this powder on kneading is as follows: After cutting the powder grains still contain 21% by weight of ethyl ether and 15% by weight of ethyl alcohol. The grains were divided into two lots:
- This apparatus consists of a thermostatically controlled enclosure 1 constituting, by its shape, a reactor, said enclosure being supplied by a regulating fluid 2.
- a pipe 3 allows the arrival of the bubbling gas 4.
- the powder and the liquid phase are agitated by means of the agitator 7.
- the interior volume of the reactor is 35 liters and its internal diameter 30 cm.
- the powder grains contained 10% by weight of ethyl alcohol and 0.10% by weight of ethyl ether, the percentages being expressed relative to the total weight of the dry matter.
- the powder grains of batch B were spun in a conventional manner at normal pressure at the rate of 8 hours in a rack at room temperature and 20 hours in a box at 30 ° C with an additional hour of cooling.
- the powders of the two batches were smoothed with centralite (symmetrical diethyl diphenyl urea) and graphitized according to the usual techniques known to those skilled in the art.
- the powders of the two batches were fired into a 30 mm gun, the shell weighed 235 grams and the powder charge was 48.2 grams.
- a powder treated according to the invention gives firing results entirely comparable to those provided by the same powder treated in a conventional manner but that the first has a chemical stability greater than the second at low temperature, which shows that nitrocellulose has been less degraded in a powder treated according to the invention than in a powder treated in a conventional manner.
Abstract
Description
La présente invention concerne un procédé d'élimination des solvants contenus dans les poudres propulsives en grains fabriquées selon le procédé dit "avec solvant", lorsque lesdits solvants sont constitués par un mélange éther-alcool.The present invention relates to a method for removing the solvents contained in the propellant powders in grains manufactured according to the so-called "solvent" method, when said solvents consist of an ether-alcohol mixture.
Dans le présent brevet on entend par poudres en grains aussi bien les poudres se présentant sous forme de grains cylindriques que celles se présentant sous forme de bandes ou de paillettes.In the present patent, grain powders are understood to mean both powders in the form of cylindrical grains and those in the form of strips or flakes.
Les poudres propulsives en grains fabriquées selon le procédé dit "avec solvant" sont en général soit des poudres à simple base à la nitrocellulose, soit des poudres dont au moins une partie de la matière énergétique est constituée par de la nitrocellulose, le restant de la matière énergétique étant constitué par les bases propulsives organiques solides bien connues de l'homme de métier, telles que, par exemple, le nitrate de polyvinyle, l'acétate de cellulose, l'acétate de polyvinyle, etc... ou des mélanges de ces corps.The propellant powders in grains manufactured according to the so-called "solvent" process are generally either powders with a simple nitrocellulose base, or powders of which at least a part of the energetic material consists of nitrocellulose, the remainder of the energetic material consisting of solid organic propellant bases well known to those skilled in the art, such as, for example, polyvinyl nitrate, cellulose acetate, polyvinyl acetate, etc. or mixtures of these bodies.
Dans un procédé classique de fabrication de poudre avec solvant, on opère comme suit :
- - on procède à une déshydratation des bases énergétiques conservées en floches à l'eau au moyen d'un alcanol qui est en général l'alcool éthylique ou l'alcool isopropylique,
- - on ajoute ensuite aux bases énergétiques déshydratées un corps organique solvant desdites bases qui est en général un éther d'alkyle tel que par exemple l'éther éthylique et on procède au malaxage desdites bases après avoir ajouté les additifs bien connus de l'homme de l'art (notamment un stabilisant chimique de la poudre qui peut être la diphénylamine ou la nitro-2 diphénylamine),
- - la pâte ainsi obtenue est alors passée à la presse à extruder et découpée,
- - on procède alors à l'opération dite d'essorage qui consiste à placer les grains de poudre en étuve à une température modérée (entre la température ambiante et 40°C en général) de manière à extraire en partie les solvants contenus dans la poudre,
- - cette opération est suivie de celle dite du trempage qui consiste à tremper les grains de poudre dans de l'eau chaude de manière à chasser de la poudre les solvants non éliminés à l'essorage et notamment l'alcool,
- - on termine ensuite par un séchage de la poudre en étuve et éventuellement, selon le type de poudre désirée, par des opérations dites de lissage ou de graphitage.
- - the energy bases stored in water flasks are dehydrated using an alkanol which is generally ethyl alcohol or isopropyl alcohol,
- - then added to the dehydrated energy bases an organic body which is a solvent for the said bases, which is generally an alkyl ether such as for example ethyl ether and the mixing of said bases is carried out after adding the additives well known to those skilled in the art (in particular a chemical stabilizer of the powder which may be diphenylamine or 2-nitro-diphenylamine) ,
- the dough thus obtained is then passed to the extruding press and cut,
- - We then proceed to the so-called spinning operation which consists of placing the grains of powder in an oven at a moderate temperature (between room temperature and 40 ° C in general) so as to partially extract the solvents contained in the powder ,
- this operation is followed by that known as soaking, which consists in soaking the grains of powder in hot water so as to expel from the powder the solvents which have not been removed by spinning and in particular the alcohol,
- - We then finish by drying the powder in an oven and possibly, depending on the type of powder desired, by so-called smoothing or graphitizing operations.
L'opération classique d'essorage à température ambiante ou légèrement supérieure à la température ambiante présente un inconvénient majeur : les pressions partielles de l'éther et de l'alcool étant voisines dans cette gamme de température, les deux solvants s'évaporent en même temps. On sait également que les molécules contenues en surface d'un grain s'évaporent plus facilement que celles contenues au coeur du grain. Par ailleurs, l'évaporation de l'éther peut provoquer une condensation de l'eau en surface du grain, ce qui entraine une reprécipi- tation de la nitrocellulose en surface, il se forme donc à la surface du grain de poudre une pellicule qui rend plus difficile la diffusion des solvants contenus au coeur du grain de poudre. C'est ce phénomène qui explique la nécessité de la longue durée de l'opération dite de trempage dont les durées, en eau chaude, sont dans beaucoup de cas voisines de 150 heures.The conventional spinning operation at room temperature or slightly above room temperature has a major drawback: the partial pressures of ether and alcohol being close to this temperature range, the two solvents evaporate at the same time time. We also know that the molecules contained on the surface of a grain evaporate more easily than those contained in the heart of the grain. Furthermore, the evaporation of the ether can cause condensation of the water on the surface of the grain, which leads to a reprecipitation of the nitrocellulose on the surface, so a film forms on the surface of the powder grain. makes the diffusion of the solvents contained in the core of the powder grain more difficult. It is this phenomenon which explains the necessity of the long duration of the so-called soaking operation, the durations of which, in hot water, are in many cases close to 150 hours.
Pendant le trempage les molécules d'éther s'oxydent et provoquent l'oxydation et la détérioration du stabilisant qui a été ajouté à la poudre. Par ailleurs pendant le trempage la nitrocellulose commence à se dégrader. Ainsi la technique classique d'essorage a pour conséquence directe une augmentation de la durée de trempage (avec les manipulations supplémentaires que cela implique) et comme conséquence indirecte une diminution de la stabilité chimique de la poudre.During soaking the ether molecules oxidize and cause oxidation and deterioration of the stabilizer which has been added to the powder. Furthermore during the soaking nitrocellulose begins to degrade. So the classic spinning technique has as a consequence this directly increases the soaking time (with the additional manipulations that this implies) and as an indirect consequence decreases the chemical stability of the powder.
On a déjà proposé de réduire les inconvénients liés à l'essorage en remplaçant, au moins partiellement, ce dernier par une élimination en milieu aqueux des solvants contenus dans les grains de poudre. Une telle technique est par exemple décrite dans le brevet français 1 185 754. Néanmoins, cette technique, si elle présente un intérêt certain sur le plan de la sécurité, ne réussit pas à résoudre les difficultés précédemment mentionnées, et les grains de poudre ainsi traités nécessitent un très long trempage en eau chaude, comme on peut le voir à la page 2 dudit brevet français 1 185 754.It has already been proposed to reduce the drawbacks associated with wringing by replacing, at least partially, the latter by elimination in an aqueous medium of the solvents contained in the grains of powder. Such a technique is for example described in French patent 1,185,754. However, this technique, if it presents a certain interest in terms of safety, does not succeed in solving the difficulties mentioned above, and the grains of powder thus treated require a very long soaking in hot water, as can be seen on
Le but de la présente invention est de remédier aux inconvénients précités en proposant un nouveau procédé d'élimination des solvants contenus dans les grains de poudres propulsives fabriquées selon un procédé avec solvants dans lequel lesdits solvants sont constitués par le mélange d'un éther et d'un alcool, procédé qui assure une élimination de l'éther de manière à éviter toute formation de pellicule en surface des grains de poudre et à permettre une réduction de la durée de trempage et par voie de conséquence une augmentation de la stabilité chimique de la poudre par une moindre dégradation de cette dernière.The object of the present invention is to remedy the aforementioned drawbacks by proposing a new process for eliminating the solvents contained in the grains of propellant powders produced according to a process with solvents in which said solvents are constituted by the mixture of an ether and of '' an alcohol, a process which ensures the elimination of ether so as to avoid any film formation on the surface of the powder grains and to allow a reduction of the soaking time and consequently an increase in the chemical stability of the powder by less degradation of the latter.
Selon l'invention on parvient à ce résultat en procédant à une élimination sélective de l'éther contenu dans les grains de poudre par une immersion de ces derniers dans un milieu liquide hydroalcoolique dans lequel on fait barboter un gaz.According to the invention, this result is achieved by performing a selective elimination of the ether contained in the powder grains by immersion of the latter in a hydroalcoholic liquid medium in which a gas is bubbled.
La demanderesse a observé qu'en procédant de la sorte on parvient à abaisser la teneur en éther dans la poudre jusqu'à la valeur souhaitée tout en conservant à cette dernière une parfaite perméabilité aux solvants. Après élimination de l'éther selon l'invention il ne reste qu'à éliminer du grain de poudre l'alcool en excès, ce qui peut être fait simplement, par exemple par un trempage en eau chaude, de courte durée par rapport à un trempage classique par lequel on veut éliminer à la fois l'alcool et l'éther résiduels.The Applicant has observed that by proceeding in this way it is possible to lower the ether content in the powder to the desired value while retaining the latter a perfect permeability to solvents. After removal of the ether according to the invention, all that remains is to remove the excess alcohol from the powder grain, which can be done simply, for example by soaking in hot water, for a short period of time. compared to a conventional soaking by which we want to remove both alcohol and residual ether.
Le procédé d'élimination des solvants selon l'invention a ainsi pour conséquence directe une réduction de la durée du trempage ultérieur et pour conséquence indirecte un gain de la stabilité chimique du grain de poudre, ainsi qu'une meilleure reproductibilité de la poudre grâce au fait que les conditions d'élimination des solvants peuvent être répétées de façon quasi identiques. Le procédé selon l'invention permet également une réduction des manipulation intermédiaires que nécessitait un trempage classique.The process for removing solvents according to the invention thus has the direct consequence of reducing the duration of the subsequent soaking and, as an indirect consequence, a gain in the chemical stability of the powder grain, as well as better reproducibility of the powder thanks to the the fact that the solvent removal conditions can be repeated almost identically. The method according to the invention also allows a reduction in the intermediate handling that a conventional soaking required.
Comme il a été dit plus haut, on procède à l'élimination de l'éther contenu dans les grains de poudres fabriquées selon le procédé dit avec solvant, lesdits solvants étant constitués par le mélange d'un alcanol et d'un éther d'alkyle, par immersion desdits grains de poudres dans une phase liquide hydroalcoolique dans laquelle circule un gaz, ladite phase hydroalcoolique étant constituée par une dilution aqueuse de l'alcanol utilisé comme solvant de ladite poudre, dans des proportions telles que ladite phase liquide hydroalcoolique titre entre 20 et 70 degrés Gay-Lussac, la température de ladite phase hydroalcoolique étant comprise entre 10 et 40°C. Ledit gaz peut être tout simplement l'air ou un gaz inerte bon vecteur dudit éther, comme par exemple l'azote. Il peut être avantageux, dans le cas de grosses installations afin d'éliminer tout risque de détonation, de commencer l'élimination de l'éther à l'aide d'un tel gaz inerte et de finir ladite élimination soit avec ledit gaz inerte, soit plus simplement avec de l'air.As mentioned above, the ether contained in the powder grains produced according to the so-called solvent process is removed, the said solvents being constituted by the mixture of an alkanol and an ether of alkyl, by immersion of said grains of powders in a hydroalcoholic liquid phase in which a gas circulates, said hydroalcoholic phase being constituted by an aqueous dilution of the alkanol used as solvent for said powder, in proportions such that said title hydroalcoholic liquid phase between 20 and 70 degrees Gay-Lussac, the temperature of said hydroalcoholic phase being between 10 and 40 ° C. Said gas can simply be air or an inert gas which is a good carrier of said ether, such as nitrogen. It may be advantageous, in the case of large installations in order to eliminate any risk of detonation, to start the elimination of the ether using such an inert gas and to finish said elimination either with said inert gas, more simply with air.
Le rapport de la masse de poudre à traiter sur la masse de la phase liquide hydroalcoolique à utiliser doit être inférieur ou égal à l'unité et de préférence voisin de 1/3.The ratio of the mass of powder to be treated to the mass of the hydroalcoholic liquid phase to be used must be less than or equal to one and preferably close to 1/3.
La phase liquide hydroalcoolique doit titrer entre 20 et 70 degrés Gay-Lussac et préférentiellement entre 30 et 50 degrés Gay-Lussac, sa température doit être comprise entre 10 et 40°C et préférentiellement entre 15 et 25°C.The hydroalcoholic liquid phase must titrate between 20 and 70 degrees Gay-Lussac and preferably between 30 and 50 degrees Gay-Lussac, its temperature must be between 10 and 40 ° C and preferably between 15 and 25 ° C.
Il est important dans le procédé selon l'invention de respecter les conditions de température. En effet, la demanderesse a observé qu'en dessous de 10°C l'élimination de l'éther se fait avec difficultés et qu'au dessus de 40°C, l'alcool s'éliminant trop vite de la poudre, une partie de l'éther reste bloquée dans le grain de poudre.It is important in the process according to the invention to respect the temperature conditions. Indeed, the Applicant has observed that below 10 ° C the elimination of ether is done with difficulty and that above 40 ° C, the alcohol being eliminated too quickly from the powder, part ether remains blocked in the powder grain.
Selon une variante préférée de l'invention, afin de favoriser la diffusion de l'éther dans ladite phase gazeuse, on assure, en plus de la circulation dudit gaz, un brassage mécanique énergique des grains de poudre immergés dans ladite phase liquide hydroalcoolique. Dans ces conditions une durée comprise entre 4 et 5 heures est en général suffisante pour atteindre une élimination quasi totale de l'éther dans les poudres de petit et moyen calibre.According to a preferred variant of the invention, in order to promote the diffusion of ether in said gas phase, in addition to the circulation of said gas, energetic mechanical stirring of the grains of powder immersed in said hydroalcoholic liquid phase is ensured. Under these conditions a duration of between 4 and 5 hours is generally sufficient to achieve an almost total elimination of the ether in small and medium-caliber powders.
Pour la mise en oeuvre du procédé selon l'invention on peut utiliser tout appareillage permettant d'assurer la circulation d'un gaz dans une phase liquide tel que par exemple un réacteur muni d'une ou plusieurs arrivées pour le gaz qui doit circuler dans la phase liquide. Selon la variante préférée de l'invention dans laquelle on veut assurer un brassage mécanique des grains de poudre, l'appareillage est équipé d'un agitateur tel que par exemple un agitateur à ancre ou à hélice. Selon une autre version préférée de l'invention, il est également recommandé que ledit appareillage soit entouré d'une enceinte thermostatée de manière à être en mesure de bien contrôler la température dans la mise en oeuvre du procédé selon l'invention.For the implementation of the process according to the invention, any apparatus can be used to ensure the circulation of a gas in a liquid phase such as for example a reactor provided with one or more inlets for the gas which must circulate in the liquid phase. According to the preferred variant of the invention in which it is desired to ensure mechanical mixing of the powder grains, the apparatus is equipped with an agitator such as for example an anchor or propeller agitator. According to another preferred version of the invention, it is also recommended that said apparatus is surrounded by a thermostatically controlled enclosure so as to be able to properly control the temperature in the implementation of the method according to the invention.
Après traitement selon l'invention, les grains de poudres peuvent soit subir un trempage de courte durée et être lissés et/ou graphités selon les techniques classiques ou encore subir un lissage-trempage en milieu liquide aqueux tel que décrit dans la demande de brevet français n° 77.11938 au nom de la demanderesse avec éventuellement un graphitage ultérieur.After treatment according to the invention, the grains of powders can either be subjected to short-term soaking and be smoothed and / or graphitized according to conventional techniques or else be subjected to smoothing-soaking in an aqueous liquid medium as described in the French patent application. n ° 77.11938 in the name of the plaintiff with possibly a later graphitization.
L'exemple qui suit, donné à titre non limitatif, illustre une mise en oeuvre particulière du procédé selon l'invention.The example which follows, given without limitation, illustrates a particular implementation of the method according to the invention.
On a traité par le procédé selon l'invention une poufre à canon dite poudre B 19 T. Il s'agit d'une poudre à simple base à la nitrocellulose, se présentant sous forme de petits cylindres de 3 mm de diamètre et de 4 mm de long percés axialement de 19 trous. La composition de cette poudre au malaxage est la suivante :
On a traité 5,6 kg de poudre B 19 T dans l'appareillage représenté à la figure 1.5.6 kg of B 19 T powder were treated in the apparatus represented in FIG. 1.
Cet appareillage se compose d'une enceinte thermostatée 1 constituant de par sa forme un réacteur, ladite enceinte étant alimentée par un fluide régulateur 2.This apparatus consists of a thermostatically controlled enclosure 1 constituting, by its shape, a reactor, said enclosure being supplied by a regulating
Ladite enceinte est recouverte par un couvercle 5 relié à un système d'aspiration permettant l'élimination des gaz 6. Une conduite 3 permet l'arrivée du gaz de barbotage 4. Une grille métallique 8, située au dessus du niveau de l'arrivée du gaz de barbotage, dont les trous sont d'un diamètre inférieur à la taille des grains de poudre, permet d'empêcher ces derniers de boucher l'arrivée du gaz de barbotage. La poudre et la phase liquide sont agitées au moyen de l'agitateur 7. Le volume intérieur du réacteur est de 35 litres et son diamètre interne de 30 cm.Said enclosure is covered by a
On a opéré dans les conditions suivantes :
Les grains de poudre du lot B ont été essorés de façon classique à pression normale à raison de 8 heures en casier à température ambiante et de 20 heures en caisson à 30°C avec en plus une heure de refroidissement.The powder grains of batch B were spun in a conventional manner at normal pressure at the rate of 8 hours in a rack at room temperature and 20 hours in a box at 30 ° C with an additional hour of cooling.
Les teneurs en solvant étaient alors les suivantes:
Il ressort nettement que, à teneurs d'alcools,comparables, le procédé selon l'invention permet une élimination très supérieure à l'éther.It is clearly apparent that, with comparable alcohol contents, the process according to the invention allows elimination much higher than ether.
A titre de comparaison supplémentaire, on a trempé de façon classique à l'eau chaude les grains de poudre des lots A et B.By way of additional comparison, the powder grains of lots A and B were conventionally quenched in hot water.
On a effectué un trempage unique des grains d'une durée de 3 heures à 60°.A single soaking of the grains lasting 3 hours at 60 ° was carried out.
Les teneurs finales en solvants des grains étaient les suivantes :
On a effectué le trempage suivant sur les poudres du lot B :
Les teneurs finales en solvants dans ce cas étaient les suivantes :
Il apparait que le procédé selon l'invention permet à la fois une meilleure élimination de l'éther et une réduction considérable de la durée du trempage.It appears that the process according to the invention allows both better elimination of the ether and a considerable reduction in the duration of the soaking.
Les poudres des deux lots ont été lissées à la centralite (diéthyl diphényl urée symétrique) et graphitées selon les techniques usuelles connues de l'homme de métier.The powders of the two batches were smoothed with centralite (symmetrical diethyl diphenyl urea) and graphitized according to the usual techniques known to those skilled in the art.
Les caractéristiques des poudres des deux lots étaient les suivantes :
Les poudres des deux lots ont été tirées dans un canon de 30 mm, l'obus pesait 235 grammes et la charge de poudre était de 48,2 grammes.The powders of the two batches were fired into a 30 mm gun, the shell weighed 235 grams and the powder charge was 48.2 grams.
Les résultats de tirs ont été les suivants :
- (1) Vitesse de l'obus à 25 mètres de la bouche du canon
- (2) Pression maximale dans la culasse.
- (1) Shell speed 25 meters from the muzzle
- (2) Maximum pressure in the cylinder head.
On observe ainsi qu'une poudre traitée selon l'invention donne des résultats de tir tout à fait comparables à ceux fournis par la même poudre traitée de façon classique mais que la première a une stabilité chimique supérieure à la seconde à basse température, ce qui montre que la nitrocellulose a été moins dégradée dans une poudre traitée selon l'invention que dans une poudre traitée de façon classique.It is thus observed that a powder treated according to the invention gives firing results entirely comparable to those provided by the same powder treated in a conventional manner but that the first has a chemical stability greater than the second at low temperature, which shows that nitrocellulose has been less degraded in a powder treated according to the invention than in a powder treated in a conventional manner.
Claims (8)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7729683A FR2404612A1 (en) | 1977-10-03 | 1977-10-03 | PROCESS FOR ELIMINATION IN A HYDROALCOHOLIC LIQUID MEDIUM OF THE SOLVENTS CONTAINED IN THE PROPULSIVE POWDERS IN GRAINS |
| FR7729683 | 1977-10-03 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0001526A1 true EP0001526A1 (en) | 1979-04-18 |
| EP0001526B1 EP0001526B1 (en) | 1981-04-29 |
Family
ID=9196037
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP78400114A Expired EP0001526B1 (en) | 1977-10-03 | 1978-09-26 | Process for the removal in a liquid water/alcohol medium of solvents present in granular powder propellants |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0001526B1 (en) |
| DE (1) | DE2860662D1 (en) |
| FR (1) | FR2404612A1 (en) |
| IT (1) | IT7869272A0 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0622605A1 (en) * | 1993-04-27 | 1994-11-02 | Neyrpic Framatome Mecanique | Method and automatic installation for neutralizing chemical ammunitions |
| FR2704640A1 (en) * | 1993-04-26 | 1994-11-04 | Snpe Ingenierie Sa | Process and installation for the destruction of muntions containing toxic agents |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2691800A (en) * | 1951-02-10 | 1954-10-19 | Olin Ind Inc | Method of recovering explosives in particular form |
| FR1185754A (en) * | 1957-11-05 | 1959-08-05 | Le Secretaire D Etat A La Defe | Process for removing and recovering solvents used in the manufacture of powders or other industrial products |
| US3622655A (en) * | 1969-04-14 | 1971-11-23 | Hercules Inc | Aqueous slurry process for drying of solvent wet double base smokeless powder |
| FR2244731A1 (en) * | 1973-09-20 | 1975-04-18 | Bofors Ab |
-
1977
- 1977-10-03 FR FR7729683A patent/FR2404612A1/en active Granted
-
1978
- 1978-09-26 EP EP78400114A patent/EP0001526B1/en not_active Expired
- 1978-09-26 DE DE7878400114T patent/DE2860662D1/en not_active Expired
- 1978-10-02 IT IT7869272A patent/IT7869272A0/en unknown
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2691800A (en) * | 1951-02-10 | 1954-10-19 | Olin Ind Inc | Method of recovering explosives in particular form |
| FR1185754A (en) * | 1957-11-05 | 1959-08-05 | Le Secretaire D Etat A La Defe | Process for removing and recovering solvents used in the manufacture of powders or other industrial products |
| US3622655A (en) * | 1969-04-14 | 1971-11-23 | Hercules Inc | Aqueous slurry process for drying of solvent wet double base smokeless powder |
| FR2244731A1 (en) * | 1973-09-20 | 1975-04-18 | Bofors Ab |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2704640A1 (en) * | 1993-04-26 | 1994-11-04 | Snpe Ingenierie Sa | Process and installation for the destruction of muntions containing toxic agents |
| US5574203A (en) * | 1993-04-26 | 1996-11-12 | Snpe Ingenierie S.A. | Process and installation for destroying munitions containing toxic agents |
| EP0622605A1 (en) * | 1993-04-27 | 1994-11-02 | Neyrpic Framatome Mecanique | Method and automatic installation for neutralizing chemical ammunitions |
| FR2704641A1 (en) * | 1993-04-27 | 1994-11-04 | Neyrpic Framatome Mecanique | Method and automatic installation of neutralization of chemical munitions. |
Also Published As
| Publication number | Publication date |
|---|---|
| IT7869272A0 (en) | 1978-10-02 |
| DE2860662D1 (en) | 1981-08-06 |
| FR2404612A1 (en) | 1979-04-27 |
| FR2404612B1 (en) | 1980-02-08 |
| EP0001526B1 (en) | 1981-04-29 |
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