Skip to main content
Article thumbnail
Location of Repository

Department of Environmental and Ordnance Systems

By J Allum

Abstract

This study investigated the formulation and characterisation of emulsion explosives. This included the manufacture of more than 120kg of emulsion explosive of which around 105kg was used on the explosive ordnance range in over 350 individual firings. For each emulsion composition, an average of eight firings was undertaken with which to substantiate the explosive performance data. The formulation was varied to determine the effects of water content upon the physical characteristics of the emulsion. These physical effects included thermal conductivity, particle size, viscosity and the explosive performance of the emulsion. In respect of explosive performance, microballoons were added to sensitise the emulsion and the proportions of microballoons added were altered to look at their effect on velocity of detonation, sensitivity and the brisance of the emulsions. Emulsion explosives are commonly referred, in literature, as Type 11 non-ideal explosives. This is due to their non-linear behaviour with respect to the variation of velocity of detonation with density. Traditionally, when an emulsion explosive was commercially manufactured, the water content has been kept at a minimum (12-17%). This was accepted as the way to achieve the best explosive performance, based upon the belief that an emulsion with the highest concentration of active ingredients, ammonium nitrate and oil, would give the best explosive performance. This study examined a wider range of emulsion explosive water contents than has been previously studied, from 12% to 35% water. It was found, during this study, that higher water content emulsions, specifically 25% water, had a marked increase in explosive performance. The highest velocity of detonation recorded was in a 39mm diameter tube, at 25% water content with 3% microballoons, was 5558ms-1. This was some 15% higher than any other VOD recorded in this study. The high velocity of detonation, at 25% water content, was one of a number of physical characteristics in which this water content varied from the other emulsion water contents. This study endeavored to show that emulsion explosives could exhibit two differing types of explosive reaction, thermal explosion and grain burning. This was based on the velocity of detonation and plate dent data, both of which indicated that there was a change in reaction with water content. Emulsion explosives, with a high water and high microballoon content, exhibited a thermal explosion type reaction. They exhibited Type I ideal explosive behaviour, with increasing velocity of detonation with density. Lower water content emulsion explosives, displayed the more commonly expected Type 11 non-ideal behaviour and reacted in a grain burning type detonation

Topics: Emulsion explosives, Explosive properties, Initiation, Detonation
Year: 2009
OAI identifier: oai:dspace.lib.cranfield.ac.uk:1826/3976
Provided by: Cranfield CERES

Suggested articles

Citations

  1. 46 'Detonics of High Explosives'
  2. 92 Private communications with
  3. (1979). Acta Cryst, doi
  4. American Instiute of Physics Handbook', 2nd Edition.
  5. (1989). An Introduction to Rheology', doi
  6. (1942). Annalen der Physik doi
  7. (1883). Annales de Chimie at de Physique, doi
  8. (1985). AppL Phys, doi
  9. (1987). Atlas Powder, doi
  10. (1988). Basic Principles of Colloid Science', doi
  11. (1949). Chemical Reviews, doi
  12. (1994). Combustion, Explosion and Shock Waves, doi
  13. Combustion: a study in theory, fact and application', doi
  14. (1906). Comptes Rendes Academie des Science,
  15. (1904). Comptes Rendes Academie des Sciences, doi
  16. Detonation in Condensed Explosives', doi
  17. (1992). Detonation of Condensed Explosives', doi
  18. (1957). Emulsions: Theory and Practice', doi
  19. (1983). Encyclopaedia of Emulsion Technology',
  20. (1960). Encyclopaedia of Explosives' Picatinny Arsenal',
  21. (1997). Eng Des,
  22. (1998). Explosive Effects and Applications', Editors: doi
  23. (1997). Explosives in the Service of
  24. (1997). Explosives in the Service of Man' Editor:
  25. (1998). Food Emulsions -What Are They? ' Emulsifiers Functionality and Applications',
  26. (1983). Hewat Acta Cryst, doi
  27. (1952). Initiation and Growth of Explosions in Liquids and Solids', doi
  28. (1994). Introduction to Colloid & Surface Chemistry', doi
  29. introduction to the Technology of Explosives',
  30. (1988). Introduction to Thermal Analysis Techniques and Applications', doi
  31. Le Chatelier, doi
  32. (1979). Numerical Modelling of Detonations', doi
  33. (1995). of Thermal Analysis, doi
  34. On the Normal Ignition Velocity of Explosive Gaseous Mixtures', doi
  35. (1988). Phase Stabilisation Of Ammonium Nitrate' Msc Thesis
  36. (1993). PhD Thesis 'Influence of Technological Parameters on the Enzymatic Reaction and Gel Formation in Milk and LIF-Retentates,
  37. (1978). Propellants and Explosives, doi
  38. (1996). Propellants, Explosives, Pyrotechnics, doi
  39. Provided by Dr.
  40. (1956). Science of High Explosives' Editor:
  41. (1998). Society of Chemical Industry,
  42. (1985). The Mathematics of Combustion', Editor doi
  43. (1958). The Science of High Explosives', doi
  44. (1960). Theory of Detonation', Z. doi
  45. Theory of Stationary Detonation Waves' Selected Works,
  46. (1948). Trans. Faraday Soc. doi
  47. Vieille Comptes Rendes Academie des Sciences,

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.