EP0206946A1 - Device for arresting an explosion during the transfer of bulk explosives - Google Patents

Device for arresting an explosion during the transfer of bulk explosives Download PDF

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Publication number
EP0206946A1
EP0206946A1 EP86401384A EP86401384A EP0206946A1 EP 0206946 A1 EP0206946 A1 EP 0206946A1 EP 86401384 A EP86401384 A EP 86401384A EP 86401384 A EP86401384 A EP 86401384A EP 0206946 A1 EP0206946 A1 EP 0206946A1
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EP
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Prior art keywords
cannula
explosive
central channel
detonation
diameter
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EP86401384A
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German (de)
French (fr)
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EP0206946B1 (en
Inventor
Pierre Vuillaume
Didier Gaston
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Charbonnages de France CDF
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Charbonnages de France CDF
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Priority to AT86401384T priority Critical patent/ATE46035T1/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42D—BLASTING
    • F42D1/00—Blasting methods or apparatus, e.g. loading or tamping
    • F42D1/08—Tamping methods; Methods for loading boreholes with explosives; Apparatus therefor
    • F42D1/10—Feeding explosives in granular or slurry form; Feeding explosives by pneumatic or hydraulic pressure

Definitions

  • the present invention relates to a device for detonating a detonation for a system for transferring explosive substances in bulk.
  • the solution currently adopted to limit the risks of transmission of the detonation through the loading cannula consists in limiting the diameter thereof to a value less than the critical detonation diameter of the pumped explosive: Indeed the critical diameter of detonation of an explosive is a value of the diameter of a cylindrical charge of this explosive below which the detonation is unable to propagate in the charge.
  • Limiting the diameter of the cannulae to 25 mm has the effect of significantly reducing the pumping rate and correspondingly increasing the loading time of the mines.
  • the duration of exposure of personnel to the risks of untimely departure is thereby increased, and the economic benefit of transferring explosives in bulk by pumping can be called into question, in particular in the case of open pit fires by vertical mines deep with priming down the hole.
  • the choice of the critical detonation diameter as a criterion for limiting the diameter of the cannulas is questionable: the value of the critical detonation diameter, which is an intrinsic characteristic of 'a given explosive, is determined under specific experimental conditions (light packaging, standardized density, etc.), and generally "once and for all" during the approval examination of the product. It is not certain that this characteristic is representative of the explosive under its normal conditions of use.
  • the invention aims to stop the detonation between an explosive transfer system and a reservoir of these materials explosives.
  • the present invention provides for this purpose a device installed on a bulk explosive material transfer system, of the type which comprises a transfer cannula in relation to at least one tank of bulk explosive materials and intended to fill a receptacle, at least in part, explosive materials; a central channel is arranged inside this cannula for the progression of the fumes in the event of an untimely explosion.
  • the known art device represented in FIG. 1 comprises two reservoirs 10 containing a certain amount of explosive 11, a cannula 13 starting from these reservoirs, a reel 12 of cannula 13 and a pump 14 arranged on a truck 15.
  • the free end 16 of the cannula 13 descends into a vertical blast hole 17, at the bottom of which a detonator 18 has previously been placed.
  • a trigger device 19 located on the surface is connected to this detonator 18 by any known means.
  • the end of the cannula is at the bottom of the blast hole 17, it then rises gradually, for example by means of a progressive rewinding of the cannula 13 on the reel 12, to always remain in contact with the surface explosive spilled into the blast hole.
  • the explosion control is carried out remotely using the trigger device 19.
  • FIG. 2 A variation curve of this critical detonation diameter with the density under normal pressure is shown in FIG. 2 for two pumpable explosives of the slurry type.
  • the device of the invention allows, in the event of an untimely explosion, to stop the detonation before it reaches the stock of explosive. This device tolerates fluctuations in the critical diameter of the pumped explosive and does not affect the pumping rate.
  • the device of the invention comprises a concentric central channel 22 disposed inside the cannula 13 over at least a part of its length. This channel is held in place by centering rings 23.
  • the device according to the invention takes advantage of a phenomenon called "channel effect": in fact, when a charge detonates under confinement and a small empty space is provided in the charge or between the charge and the confinement, the fumes produced by the decomposition of the explosive can reach a speed greater than the detonation speed of the explosive. The fumes then propagate in the empty space in front of the detonation front. Their pressure is such that they can desensitize the explosive by compression, causing the detonation to stop.
  • FIG. 4 shows the direction 24 of flow of the explosive and the direction 25 of propagation of the fumes in the event of an untimely explosion in the blast hole, the cannula being still disposed therein.
  • the difference in length between the outer tube 26 and the central core 27 aims to provide a length of 250 mm allowing the detonation to reach its steady state.
  • the detonation stops before the end of the test device the length traveled increases when the inside diameter of the outer tube increases or when the critical detonation diameter of the explosive decreases.
  • the diameter of the hollow core was 10 and 15Z of the diameter of the filler. Values of this order of magnitude seem optimal for the device of the invention.
  • the material of the external tube does not matter, as long as it resists pumping pressures, on the other hand the internal tube must be sufficiently resistant to the pressures of a few bars generated by pumping, but conversely sufficiently deformable or brittle to allow the action of smoke on the explosive.
  • the minimum length of the channel causing, with good certainty, the detonation to stop is all the more important as the diameter of the external tube is large for a core of given diameters.
  • a minimum length of approximately 2 m i.e. a length greater than 25 times the internal diameter of the cannula, would guarantee a very acceptable level of safety since the tests were successful for a length of 0.85 m.
  • such a core is advantageously disposed over the entire length of the cannula downstream of the pump, which can lead to positioning in the cannula a flexible hollow core over several tens of meters in length.
  • the blast hole can be a receptacle of any shape.
  • the device of the invention can be installed on any bulk explosive material transfer system.

Abstract

L'invention concerne un dispositif d'arrêt de la détonation pour transfert de matières explosives en vrac, dans les mines, carrières et travaux publics, du type qui comporte une canule (13) de transfert en relation avec un réservoir de matières explosives en vrac et destinée à remplir un réceptacle, au moins en partie, de matières explosives.Un canal central (22) est disposé à l'intérieur de cette canule pour la progression des fumées en cas d'explosion intempestive.The invention relates to a detonation arresting device for the transfer of bulk explosive materials, in mines, quarries and public works, of the type which comprises a transfer cannula (13) in relation to a reservoir of bulk explosive materials and intended to fill a receptacle, at least in part, with explosive materials. A central channel (22) is arranged inside this cannula for the progression of smoke in the event of an untimely explosion.

Description

La présente invention concerne un dispositif d'arrêt d'une détonation pour système de transfert de matières explosives en vrac.The present invention relates to a device for detonating a detonation for a system for transferring explosive substances in bulk.

Au cours du transfert d'explosifs en vrac, la présence d'un détonateur au fond du trou de mine augmente les risques d'explosion intempestive. Pour limiter les conséquences d'une telle explosion consécutive par exemple à des perturbations électriques (orage....) il importe qu'une détonation amorcée dans le trou de mine (qui peut contenir jusqu'à plusieurs centaines de kilos d'explosif dans les exploitations à ciel ouvert) ne puisse se transmettre à travers la canule de chargement jusqu'au stock d'explosif en vrac, généralement constitué par un ou plusieurs réservoirs, dont la masse totale sur un même site peut être de plusieurs tonnes et dont l'explosion pourrait avoir des conséquences catastrophiques.During the transfer of explosives in bulk, the presence of a detonator at the bottom of the blast hole increases the risk of inadvertent explosion. To limit the consequences of such an explosion, for example caused by electrical disturbances (thunderstorm, etc.), it is important that a detonation initiated in the blast hole (which can contain up to several hundred kilos of explosive in open pit operations) cannot be transmitted through the loading cannula to the bulk explosive stock, generally consisting of one or more reservoirs, the total mass of which on the same site may be several tonnes and of which l explosion could have catastrophic consequences.

Compte tenu de la vitesse élevée de propagation de la détonation dans une charge d'explosif cylindrique (plusieurs kilomètres par seconde), ainsi que des effets destructeurs de l'onde de choc entraînée par la détonation, la réalisation d'un système d'arrêt de la détonation par des procédés mécaniques simples est difficilement envisageable.Given the high speed of propagation of the detonation in a charge of cylindrical explosive (several kilometers per second), as well as the destructive effects of the shock wave caused by the detonation, the implementation of a stop system detonation by simple mechanical methods is difficult to envisage.

La solution actuellement retenue pour limiter les risques de transmission de la détonation à travers,la canule de chargement consiste à limiter le diamètre de celle-ci à une valeur inférieure au diamètre critique de détonation de l'explosif pompé : En effet le diamètre critique de détonation d'un explosif est une valeur du diamètre d'une charge cylindrique de cet explosif en dessous de laquelle la détonation est incapable de se propager dans la charge.The solution currently adopted to limit the risks of transmission of the detonation through the loading cannula consists in limiting the diameter thereof to a value less than the critical detonation diameter of the pumped explosive: Indeed the critical diameter of detonation of an explosive is a value of the diameter of a cylindrical charge of this explosive below which the detonation is unable to propagate in the charge.

Cette solution a été retenue dans la réglementation française du pompage des explosifs dans les mines et carrières : en présence d'un détonateur en fond de trou, le diamètre de la canule de chargement d'explosif par pompage doit être limité à 25 mm, qui est une valeur en principe inférieure aux diamètres critiques de détonation de tous les explosifs dont le chargement par pompage est autorisé en France.This solution has been adopted in French regulations for the pumping of explosives in mines and quarries: in the presence of a downhole detonator, the diameter of the explosive loading cannula pumping must be limited to 25 mm, which is in principle less than the critical detonation diameters of all explosives the loading of which by pumping is authorized in France.

La limitation à 25 mm du diamètre des canules a pour effet de diminuer de façon importante le débit de pompage et d'augmenter corrélativement la durée de chargement des mines. La durée d'exposition du personnel aux risques de départ intempestif s'en trouve accrue, et l'intérêt économique du transfert d'explosifs en vrac par pompage peut être remis en cause, notamment dans le cas de tirs en ciel ouvert par mines verticales profondes avec amorçage en fond de trou.Limiting the diameter of the cannulae to 25 mm has the effect of significantly reducing the pumping rate and correspondingly increasing the loading time of the mines. The duration of exposure of personnel to the risks of untimely departure is thereby increased, and the economic benefit of transferring explosives in bulk by pumping can be called into question, in particular in the case of open pit fires by vertical mines deep with priming down the hole.

Mais en matière d'explosifs pompables, qui sont par exemple des explosifs bouillie ou émulsion, le choix du diamètre critique de détonation comme critère de limitation du diamètre des canules est discutable : la valeur du diamètre critique de détonation, qui est une caractéristique intrinsèque d'un explosif donné, est déterminée dans des conditions expérimentales particulières (encartouchage léger, densité normalisée, .. ..), et généralement "une fois pour toutes" lors de l'examen d'agrément du produit. Il n'est pas sûr que cette caractéristique soit représentative de l'explosif dans ses conditions normales d'utilisation.But with regard to pumpable explosives, which are for example boiled or emulsion explosives, the choice of the critical detonation diameter as a criterion for limiting the diameter of the cannulas is questionable: the value of the critical detonation diameter, which is an intrinsic characteristic of 'a given explosive, is determined under specific experimental conditions (light packaging, standardized density, etc.), and generally "once and for all" during the approval examination of the product. It is not certain that this characteristic is representative of the explosive under its normal conditions of use.

En particulier, le confinement apporté par le caoutchouc armé des canules de chargement peut avoir pour effet de diminuer légèrement la valeur du diamètre critique de détonation. Mais ce dernier peut aussi dépendre étroitement de la densité de l'explosif dans ses conditions d'utilisation. Cette densité des explosifs pompables peut subir d'importantes variations en fonction:

  • - de la pression à laquelle est soumis le produit dans la canule au cours du pompage. Cette influence va toutefois en général dans le sens de la sécurité. En effet, des pressions de l'ordre de quelques bars, couramment atteintes en sortie de pompe peuvent suffire à désensibiliser les explosifs.
  • - d'impératifs commerciaux qui imposent aux fabricants de régler les densités de leurs produits, ce qui s'effectue par des procédés mécaniques (brassage d'aération), ou chimiques (variation de la quantité d'agent allégeant ou émulsifiant).
In particular, the confinement provided by the reinforced rubber of the loading cannulas can have the effect of slightly reducing the value of the critical detonation diameter. However, the latter may also depend closely on the density of the explosive under its conditions of use. This density of pumpable explosives can undergo significant variations depending on:
  • - the pressure to which the product is subjected in the cannula during pumping. However, this influence generally goes in the direction of security. Indeed, pressures of the order of a few bars, commonly reached at the pump outlet can be enough to desensitize explosives.
  • - commercial imperatives which require manufacturers to regulate the densities of their products, which is done by mechanical (ventilation mixing), or chemical (variation in the quantity of lightening or emulsifying agent) processes.

En définitive, non seulement la règle actuelle de limitation du diamètre des canules de pompage présente des inconvénients majeurs du point de vue des conditions pratiques de pompage, mais elle ne garantit pas dans certains cas la non-transmission de la détonation depuis le fond du trou de mine jusqu'aux réservoirs d'explosif.In short, not only does the current rule for limiting the diameter of pumping cannulas have major drawbacks from the point of view of practical pumping conditions, but it does not in certain cases guarantee the non-transmission of the detonation from the bottom of the hole from mine to explosive tanks.

Pour pallier ces inconvénients, tout en tolérant des fluctuations du diamètre critique des matières explosives transférées et sans affecter le débit de transfert, l'invention a pour objet d'arrêter la détonation entre un système de transfert d'explosif et un réservoir de ces matières explosives.To overcome these drawbacks, while tolerating fluctuations in the critical diameter of the explosive materials transferred and without affecting the transfer rate, the invention aims to stop the detonation between an explosive transfer system and a reservoir of these materials explosives.

La présente invention propose à cet effet un dispositif installé sur un système de transfert de matières explosives en vrac, du type qui comporte une canule de transfert en relation avec au moins un réservoir de matières explosives en vrac et destinée à remplir un réceptacle, au moins en partie, de matières explosives; un canal central est disposé à l'intérieur de cette canule pour la progression des fumées en cas d'explosion intempestive.The present invention provides for this purpose a device installed on a bulk explosive material transfer system, of the type which comprises a transfer cannula in relation to at least one tank of bulk explosive materials and intended to fill a receptacle, at least in part, explosive materials; a central channel is arranged inside this cannula for the progression of the fumes in the event of an untimely explosion.

Les caractéristiques et avantages de l'invention ressortiront d'ailleurs de la description qui va suivre à titre d'exemple non limitatif, en référence aux dessins annexés sur lesquels :

  • - la figure 1 représente un dispositif de l'art connu dans le cas d'une mine à ciel ouvert;
  • - les figures 2 et 3 représentent deux courbes caractéristiques de deux explosifs donnés;
  • - la figure 4 est une vue en coupe longitudinale du dispositif de l'invention;
  • - la figure 5 est une vue en coupe transversale, selon la flèche V, du dispositif représenté à la figure 4.
  • - la figure 6 représente un dispositif utilisé pour expérimenter l'invention.
The characteristics and advantages of the invention will become apparent from the description which follows by way of nonlimiting example, with reference to the appended drawings in which:
  • - Figure 1 shows a device of the known art in the case of an open pit;
  • - Figures 2 and 3 show two characteristic curves of two given explosives;
  • - Figure 4 is a longitudinal sectional view of the device of the invention;
  • FIG. 5 is a cross-sectional view, along arrow V, of the device shown in FIG. 4.
  • - Figure 6 shows a device used to experiment with the invention.

Suivant la forme de réalisation choisie et représentée le dispositif de l'art connu représenté à la figure 1 comprend deux réservoirs 10 contenant une certaine quantité d'explosif 11, une canule 13 partant de ces réservoirs, un enrouleur 12 de canule 13 et une pompe 14 disposés sur un camion 15.According to the embodiment chosen and shown, the known art device represented in FIG. 1 comprises two reservoirs 10 containing a certain amount of explosive 11, a cannula 13 starting from these reservoirs, a reel 12 of cannula 13 and a pump 14 arranged on a truck 15.

Dans la suite de la description l'expression de "pompage" correspond en fait ici à un refoulement d'explosif par la pompe en travers de la canule 13.In the following description, the expression “pumping” in fact corresponds here to a repression of explosive by the pump across the cannula 13.

L'extrémité 16 libre de la canule 13 descend dans un trou de mine 17 vertical, dans le fond duquel a préalablement été placé un détonateur 18.The free end 16 of the cannula 13 descends into a vertical blast hole 17, at the bottom of which a detonator 18 has previously been placed.

Un dispositif de déclenchement 19 situé en surface est relié à ce détonateur 18 par tout moyen connu.A trigger device 19 located on the surface is connected to this detonator 18 by any known means.

En début de chargement l'extrémité de la canule se trouve au fond du trou de mine 17, elle remonte ensuite progressivement, par exemple grâce à un rembobinage progressif de la canule 13 sur l'enrouleur 12, pour rester toujours en contact avec la surface de l'explosif déversé dans le trou de mine.At the start of loading the end of the cannula is at the bottom of the blast hole 17, it then rises gradually, for example by means of a progressive rewinding of the cannula 13 on the reel 12, to always remain in contact with the surface explosive spilled into the blast hole.

En fonctionnement normal, après avoir chargé par pompage une partie du trou de mine avec de l'explosif en vrac, la commande d'explosion est effectuée à distance grâce au dispositif de déclenchement 19.In normal operation, after having loaded a portion of the blast hole with bulk explosive by pumping, the explosion control is carried out remotely using the trigger device 19.

Mais au cours de cette phase de chargement par pompage la présence du détonateur 18 au fond du trou de mine 17 augmente les risques d'explosion accidentelle dues par exemple à des chocs mécaniques ou à des perturbations électriques.But during this pumping loading phase, the presence of the detonator 18 at the bottom of the blast hole 17 increases the risk of accidental explosion due for example to mechanical shock or electrical disturbance.

Pour limiter ces risques la solution de l'art connu consiste à limiter le diamètre de la canule au dessous d'un seuil correspondant au diamètre critique de détonation de l'explosif pompé.To limit these risks the art solution known is to limit the diameter of the cannula below a threshold corresponding to the critical detonation diameter of the pumped explosive.

Une courbe de variation de ce diamètre critique de détonation avec la densité sous pression normale est représentée à la figure 2 pour deux explosifs pompables de type bouillie.A variation curve of this critical detonation diameter with the density under normal pressure is shown in FIG. 2 for two pumpable explosives of the slurry type.

Une courbe de variation de la densité en fonction de la pression de l'une de ces bouillies est représentée à la figure 3.A curve of variation of the density as a function of the pressure of one of these slurries is shown in Figure 3.

Le dispositif de l'invention permet, en cas d'explosion intempestive, d'arrêter la détonation avant qu'elle n'atteigne le stock d'explosif. Ce dispositif tolère des fluctuations du diamètre critique de l'explosif pompé et n'affecte pas le débit de pompage.The device of the invention allows, in the event of an untimely explosion, to stop the detonation before it reaches the stock of explosive. This device tolerates fluctuations in the critical diameter of the pumped explosive and does not affect the pumping rate.

Suivant la forme de réalisation choisie et représentée aux figures 4 et 5, le dispositif de l'invention comprend un canal 22 central concentrique disposé à l'intérieur de la canule 13 sur au moins une partie de longueur de celle-ci. Ce canal est maintenu en place par des anneaux de centrage 23.According to the embodiment chosen and shown in Figures 4 and 5, the device of the invention comprises a concentric central channel 22 disposed inside the cannula 13 over at least a part of its length. This channel is held in place by centering rings 23.

Le dispositif selon l'invention met à profit un phénomène appelé "effet canal" : en effet, lorsqu'une charge détone sous confinement et qu'un espace vide de faible dimension est ménagé dans la charge ou entre la charge et le confinement, les fumées produites par la décomposition de l'explosif peuvent atteindre une vitesse supérieure à la vitesse de détonation de l'explosif. Les fumées se propagent alors dans l'espace vide en avant du front de détonation. Leur pression est telle qu'elles peuvent désensibiliser l'explosif par compression, entraînant l'arrêt de la détonation.The device according to the invention takes advantage of a phenomenon called "channel effect": in fact, when a charge detonates under confinement and a small empty space is provided in the charge or between the charge and the confinement, the fumes produced by the decomposition of the explosive can reach a speed greater than the detonation speed of the explosive. The fumes then propagate in the empty space in front of the detonation front. Their pressure is such that they can desensitize the explosive by compression, causing the detonation to stop.

Sur la figure 4 ont été représentés le sens 24 d'écoulement de l'explosif et le sens 25 de propagation des fumées en cas d'explosion intempestive dans le trou de mine, la canule étant encore disposée dans celui-ci.FIG. 4 shows the direction 24 of flow of the explosive and the direction 25 of propagation of the fumes in the event of an untimely explosion in the blast hole, the cannula being still disposed therein.

Des essais de propagation de la détonation utilisant deux dispositifs expérimentaux de même structure représentée à la figure 6 ont été réalisés avec les deux explosifs pompables précités.Detonation propagation tests using two experimental devices of the same structure shown in FIG. 6 were carried out with the two aforementioned pumpable explosives.

Dans ces dispositifs, le canal de progression des fumées est central, dans l'axe de la charge. Ces dispositifs sont constitués par :

  • - un tube extérieur 26 en polychlorure de vinyle ou "PVC" ayant respectivement des diamètres intérieur et extérieur de 53 et 63 mm, et une longueur de 1100 mm avec noyau 27 creux central en tube "PVC" ayant des diamètres intérieur et extérieur de 8 et 10 mm, et une longueur de 850 mm, centré à l'aide de plusieurs anneaux 30 en fil de fer;
  • - un tube extérieur 26 en "PVC" ayant des diamètres intérieur et extérieur de 75 et 80 mm, et une longueur de 1100 mm avec noyau creux 27 central en tube "PVC" ayant des diamètres intérieur et extérieur de 8 et 10 mm, et une longueur de 850 mm, centré à l'aide de plusieurs anneaux 30 en fil de fer.
In these devices, the smoke progression channel is central, in the axis of the load. These devices consist of:
  • - an outer tube 26 of polyvinyl chloride or "PVC" having respectively inside and outside diameters of 53 and 63 mm, and a length of 1100 mm with a central hollow core 27 in tube "PVC" having inside and outside diameters of 8 and 10 mm, and a length of 850 mm, centered using several wire rings 30;
  • an outer tube 26 made of "PVC" having internal and external diameters of 75 and 80 mm, and a length of 1100 mm with a central hollow core 27 made of "PVC" tube having internal and external diameters of 8 and 10 mm, and a length of 850 mm, centered using several 30 wire rings.

La différence de longueur entre tube 26 extérieur et noyau central 27 a pour objectif de ménager une longueur de 250 mm permettant à la détonation d'atteindre son régime permanent.The difference in length between the outer tube 26 and the central core 27 aims to provide a length of 250 mm allowing the detonation to reach its steady state.

L'explosif remplissant l'espace annulaire entre noyau 27 et tube 26 externe est amorcé au moyen d'un détonateur 28 et d'un relais 29 d'explosif plastique. La propagation éventuelle de la détonation est contrôlée par:

  • - marquage de plaques de plomb;
  • - sonde résistante de longueur 850 mm à l'extrémité du dispositif;
  • - vérification du non-amorçage d'un brin de cordeau détonant à l'extrémité de la charge.
The explosive filling the annular space between core 27 and external tube 26 is primed by means of a detonator 28 and a relay 29 of plastic explosive. The possible propagation of the detonation is controlled by:
  • - marking of lead plates;
  • - resistant probe 850 mm long at the end of the device;
  • - verification of the non-initiation of a strand of detonating cord at the end of the charge.

Les résultats sont présentés dans le tableau 1 situé en fin de description, où figure :

  • - le nombre de détonations observées sur le nombre d'essais effectués;
  • - le rapport de la longueur L de propagation de la longueur totale Lo du noyau central 27, les longueurs étant mesurées à partir de l'origine du noyau creux central.
The results are presented in Table 1 located at the end of the description, where:
  • - the number of detonations observed on the number of tests carried out;
  • - The ratio of the length L of propagation of the total length Lo of the central core 27, the lengths being measured from the origin of the central hollow core.

Dans tous les cas, la détonation s'arrête avant l'extrémité du dispositif d'essai, la longueur parcourue augmentant quand le diamètre intérieur du tube externe augmente ou quand le diamètre critique de détonation de l'explosif diminue.In all cases, the detonation stops before the end of the test device, the length traveled increases when the inside diameter of the outer tube increases or when the critical detonation diameter of the explosive decreases.

Dans les essais, le diamètre du noyau creux était de 10 et 15Z du diamètre de la charge. Des valeurs de cet ordre de grandeur semblent optimales pour le dispositif de l'invention.In the tests, the diameter of the hollow core was 10 and 15Z of the diameter of the filler. Values of this order of magnitude seem optimal for the device of the invention.

Le matériau constitutif du tube externe importe peu, du moment qu'il résiste aux pressions de pompage, par contre le tube interne doit être suffisamment résistant vis-à-vis des pressions de quelques bars engendrées par le pompage, mais à l'inverse suffisamment déformable ou friable pour permettre l'action des fumées sur l'explosif.The material of the external tube does not matter, as long as it resists pumping pressures, on the other hand the internal tube must be sufficiently resistant to the pressures of a few bars generated by pumping, but conversely sufficiently deformable or brittle to allow the action of smoke on the explosive.

La longueur minimale du canal provoquant avec une bonne certitude l'arrêt de la détonation est d'autant plus importante que le diamètre du tube externe est grand pour un noyau de diamètres donnés. Pour un diamètre de ce tube de 75 mm avec un noyau creux de 10 mm, qui ne devrait pas constituer d'entrave au débit de pompage, une longueur minimale d'environ 2 m, c'est-à-dire une longueur supérieure à 25 fois le diamètre interne de la canule, garantirait un niveau de sécurité très acceptable puisque les essais ont été concluants pour une longueur de 0,85 m. Pratiquement, un tel noyau est avantageusement disposé sur toute la longueur de la canule en aval de la pompe, ce qui peut conduire à positionner dans la canule un noyau creux souple sur plusieurs dizaines de mètres de longueur.The minimum length of the channel causing, with good certainty, the detonation to stop is all the more important as the diameter of the external tube is large for a core of given diameters. For a diameter of this tube of 75 mm with a hollow core of 10 mm, which should not constitute an obstacle to the pumping rate, a minimum length of approximately 2 m, i.e. a length greater than 25 times the internal diameter of the cannula, would guarantee a very acceptable level of safety since the tests were successful for a length of 0.85 m. In practice, such a core is advantageously disposed over the entire length of the cannula downstream of the pump, which can lead to positioning in the cannula a flexible hollow core over several tens of meters in length.

L'invention n'est, bien entendu, pas limitée aux détails des formes de réalisation que l'on vient de considérer à titre d'exemple.The invention is, of course, not limited to the details of the embodiments which have just been considered by way of example.

Le trou de mine peut être un réceptacle de forme quelconque.The blast hole can be a receptacle of any shape.

Le dispositif de l'invention peut être installé sur tout système de transfert de matières explosives en vrac.The device of the invention can be installed on any bulk explosive material transfer system.

Un dispositif localisé peut être monté, par exemple :

  • - à l'extrémité terminale de la canule destinée à descendre dans un trou de mine 17;
  • - ou entre l'enrouleur 12 et les réservoirs 10, auquel cas un écran doit être positionné entre enrouleur et réservoirs pour protéger ces derniers des éclats résultant de l'explosion dans l'enrouleur.
    Figure imgb0001
A localized device can be mounted, for example:
  • - At the terminal end of the cannula intended to descend into a blast hole 17;
  • - Or between the reel 12 and the tanks 10, in which case a screen must be positioned between the reel and the tanks to protect the latter from splinters resulting from the explosion in the reel.
    Figure imgb0001

Claims (9)

1. Dispositif installé sur un système de transfert de matières explosives en vrac, du type qui comporte une canule (13) de transfert en relation avec au moins un réservoir (10) de matières explosives en vrac et destiné à remplir un réceptacle, au moins en partie, de matières explosives (11), caractérisé en ce qu'un canal central (22) est disposé à l'intérieur de cette canule (13) pour la progression des fumées en cas d'explosion intempestive.1. Device installed on a bulk explosive material transfer system, of the type which comprises a transfer cannula (13) in relation to at least one tank (10) of bulk explosive materials and intended to fill a receptacle, at least partly, of explosive materials (11), characterized in that a central channel (22) is arranged inside this cannula (13) for the progression of the fumes in the event of an untimely explosion. 2. Dispositif selon la revendication 1, caractérisé en ce que le diamètre interne de ce canal central (22) est supérieur à environ 10Z du diamètre interne de la canule (13).2. Device according to claim 1, characterized in that the internal diameter of this central channel (22) is greater than approximately 10Z of the internal diameter of the cannula (13). 3. Dispositif selon la revendication 1, caractérisé en ce que le diamètre interne de ce canal central (22) est inférieur à environ 15Z du diamètre intérieur de la canule (13).3. Device according to claim 1, characterized in that the internal diameter of this central channel (22) is less than about 15Z of the internal diameter of the cannula (13). 4. Dispositif selon l'une quelconque des revendications 1 à 3, caractérisé en ce que le canal central (22) a une longueur supérieure à 25 fois le diamètre interne de la canule.4. Device according to any one of claims 1 to 3, characterized in that the central channel (22) has a length greater than 25 times the internal diameter of the cannula. 5. Dispositif selon l'une quelconque des revendications 1 à 4, caractérisé en ce que le canal central (22) est maintenu dans la canule par des anneaux de centrage (23).5. Device according to any one of claims 1 to 4, characterized in that the central channel (22) is held in the cannula by centering rings (23). 6. Dispositif selon l'une quelconque des revendications 1 à 5, caractérisé en ce que le canal central (22) est disposé dans la canule entre un réservoir (10) dans lequel sont stockées les matières explosives (11) et le réceptacle (17).6. Device according to any one of claims 1 to 5, characterized in that the central channel (22) is disposed in the cannula between a reservoir (10) in which the explosive materials (11) are stored and the receptacle (17 ). 7. Dispositif selon l'une quelconque des revendications 1 à 5 caractérisé en ce que, la canule (13) étant formée de deux tronçons de part et d'autre d'un enrouleur (12), le canal central (22) est disposé dans cette canule entre l'enrouleur (12) sur lequel cette canule (13) est emmagasinée et le réceptacle (17).7. Device according to any one of claims 1 to 5 characterized in that, the cannula (13) being formed of two sections on either side of a reel (12), the central channel (22) is disposed in this cannula between the retractor (12) on which this cannula (13) is stored and the receptacle (17). 8. Dispositif selon l'une quelconque des revendications 1 à 5, caractérisé en ce que, la canule C13) étant formée de deux tronçons de part et d'autre d'un enrouleur (12), le canal central (22) est disposé dans cette canule entre l'enrouleur (12), sur lequel cette canule (13) est emmagasinée, et le réservoir (10) dans lequel sont stockées les matières explosives (11), un écran étant disposé entre ce réservoir (10) et cet enrouleur (12).8. Device according to any one of claims 1 to 5, characterized in that, the cannula C13) being formed of two sections on either side of a reel (12), the central channel (22) is arranged in this cannula between the reel (12), on which this cannula (13) is stored, and the tank (10) in which the explosive materials (11) are stored, a screen being arranged between this tank (10) and this reel (12). 9. Application du dispositif selon l'une quelconque des revendications 1 à 8, dans les mines, carrières et travaux publics, le réceptacle (17) étant un trou de mine.9. Application of the device according to any one of claims 1 to 8, in mines, quarries and public works, the receptacle (17) being a blast hole.
EP86401384A 1985-06-26 1986-06-24 Device for arresting an explosion during the transfer of bulk explosives Expired EP0206946B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT86401384T ATE46035T1 (en) 1985-06-26 1986-06-24 DEVICE FOR REMOVAL OF EXPLOSIONS WHEN CONVEYING FLOWABLE EXPLOSIVES.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8509719A FR2584178B1 (en) 1985-06-26 1985-06-26 DETONATION STOPPING DEVICE FOR BULK EXPLOSIVE MATERIAL TRANSFER
FR8509719 1985-06-26

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EP0206946A1 true EP0206946A1 (en) 1986-12-30
EP0206946B1 EP0206946B1 (en) 1989-08-30

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EP (1) EP0206946B1 (en)
JP (1) JPS6210600A (en)
AT (1) ATE46035T1 (en)
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ZA (1) ZA864639B (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE462508B (en) * 1988-03-15 1990-07-02 Bengt Raadman PROCEDURE AND DEVICE FOR INTRODUCING EXPLOSIVE SUBSTANCES IN DRILL
US5352429A (en) * 1992-07-14 1994-10-04 The United States Of America As Represented By The Secretary Of The Navy Dynamic compaction processing system
AUPM980994A0 (en) * 1994-12-02 1994-12-22 Ici Australia Operations Proprietary Limited Apparatus and process for explosives blow loading
NO307717B1 (en) * 1997-09-12 2000-05-15 Dyno Ind Asa Method of charging and sensitizing a slurry explosive in a borehole
US6412415B1 (en) * 1999-11-04 2002-07-02 Schlumberger Technology Corp. Shock and vibration protection for tools containing explosive components
US6401588B1 (en) * 2000-02-17 2002-06-11 Dyno Nobel Inc. Delivery of emulsion explosive compositions through an oversized diaphragm pump
ZA200104658B (en) * 2000-07-03 2001-12-12 Sasol Chemical Ind Ltd Method and system for delivery of water-based explosives.
US7660916B2 (en) * 2005-06-16 2010-02-09 Agere Systems Inc. Emulation of independent active DMA channels with a single DMA capable bus master hardware and firmware
US7971534B2 (en) * 2005-09-19 2011-07-05 Waldock Kevin H Mobile platform for the delivery of bulk explosive
ES2955739A1 (en) * 2022-04-28 2023-12-05 Blast Consult S L EXPLOSIVE LOADING SYSTEM AND PROCEDURE IN HOLES (Machine-translation by Google Translate, not legally binding)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2903969A (en) * 1953-05-28 1959-09-15 Maumee Collieries Co Method of blasting
US3713360A (en) * 1971-06-25 1973-01-30 Olin Corp Safety container for explosive powder
US4102240A (en) * 1977-01-03 1978-07-25 Cook Merrill A Blasting slurry pump truck

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1198584A (en) * 1957-04-25 1959-12-08 Nitroglycerin Ab Device for loading blastholes with explosives
US3064572A (en) * 1958-01-13 1962-11-20 Union Carbide Corp Method of and means for providing a charge of water sensitive explosive in a blast hole
US4074629A (en) * 1975-06-25 1978-02-21 Colgate Stirling A Blasting agent and method
DE2602924A1 (en) * 1976-01-27 1977-07-28 Niepmann Ag Walchwil METHOD AND APPARATUS FOR THE PRODUCTION OF EXTRUSION SLUDGE
US4098189A (en) * 1976-09-28 1978-07-04 Harry Holm Method and apparatus for preparing an explosive charge
SU652324A1 (en) * 1977-12-15 1979-03-15 Центральное Проектное Конструкторское Технологическое Бюро Министерства Цветной Металлургии Казахской Сср Arrangement for moving explosive charge hose in a borehole
US4526633A (en) * 1982-11-08 1985-07-02 Ireco Incorporated Formulating and delivery system for emulsion blasting
CA1190421A (en) * 1983-06-09 1985-07-16 Horst F. Marz Charging large diameter vertical boreholes

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2903969A (en) * 1953-05-28 1959-09-15 Maumee Collieries Co Method of blasting
US3713360A (en) * 1971-06-25 1973-01-30 Olin Corp Safety container for explosive powder
US4102240A (en) * 1977-01-03 1978-07-25 Cook Merrill A Blasting slurry pump truck

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
INDUSTRIAL AND ENGINEERING CHEMISTRY, INDUSTRIAL SECTION, vol. 60, no. 7, juillet 1968, pages 44-55; M.A. COOK: "Explosives - a survey of technical advances" *

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AU579552B2 (en) 1988-11-24
ZA864639B (en) 1987-02-25
ATE46035T1 (en) 1989-09-15
FR2584178A1 (en) 1987-01-02
DE3665360D1 (en) 1989-10-05
CA1261675A (en) 1989-09-26
JPS6210600A (en) 1987-01-19
FR2584178B1 (en) 1987-12-24
US4699060A (en) 1987-10-13
AU5916386A (en) 1987-01-08
EP0206946B1 (en) 1989-08-30

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