U.S. patent number 3,926,119 [Application Number 05/436,591] was granted by the patent office on 1975-12-16 for explosive device.
This patent grant is currently assigned to Tyler Holding Company. Invention is credited to Gerald L. Hurst, Oldrich Machacek.
United States Patent |
3,926,119 |
Hurst , et al. |
December 16, 1975 |
**Please see images for:
( Certificate of Correction ) ** |
Explosive device
Abstract
A device is provided which carries a solid particulate primary
component for a liquid-solid explosive which includes a container
having an opening for receiving the liquid component and which
carries a sensitized particulate material such as an oxidizing
material as the solid primary component adjacent a cap well on the
container, and a chamber for carrying a secondary charge or
liquid-solid explosive charge component such as a particulate
oxidizing material as a solid particulate secondary component, the
primary component and the chamber being separated in the container
by a porous member which will pass the liquid component but neither
of the solid components. A cap sensitive explosive composition is
formed, for example, by pouring a liquid component through the
opening of the container and into the chamber and allowing it to
admix with both the solid primary component and the solid secondary
component.
Inventors: |
Hurst; Gerald L. (Dallas,
TX), Machacek; Oldrich (Dallas, TX) |
Assignee: |
Tyler Holding Company (Dallas,
TX)
|
Family
ID: |
23733043 |
Appl.
No.: |
05/436,591 |
Filed: |
January 28, 1974 |
Current U.S.
Class: |
102/501; 102/315;
102/331; 102/317 |
Current CPC
Class: |
C06B
47/00 (20130101); F42B 3/02 (20130101); F42B
3/00 (20130101) |
Current International
Class: |
F42B
3/02 (20060101); F42B 3/00 (20060101); C06B
47/00 (20060101); F42B 003/00 () |
Field of
Search: |
;102/22-24,28
;149/14-17 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Pendegrass; Verlin R.
Attorney, Agent or Firm: Richards, Harris & Medlock
Claims
We claim:
1. An explosive device which includes a particulate primary solid
component and a particulate secondary solid component, which solid
components are both actuated by a liquid component, comprising:
a. a container forming an enclosure and at least one sealable
opening for adding said liquid component therein;
b. a bed comprising sensitized particulate material selected from
oxidizing and non-oxidizing material having a particle size smaller
than about 3000 microns and positioned within said enclosure
forming said particulate primary solid component;
c. porous retaining means which will pass the said liquid component
but not said primary or secondary solid components, said porous
retaining means separating said particulate solid primary component
from the remainder of the cavity within said enclosure; and
d. a bed comprising solid particulate oxidizing material forming
said particulate secondary solid component and positioned within
the said remainder of said cavity.
2. The explosive device of claim 1 further comprising capwell means
on said container positioned adjacent said primary solid
component.
3. The explosive device of claim 1 wherein said particulate primary
solid component comprises non-oxidizing particules selected from
diatomaceous earth and expanded low density silica; and a minor
effective quantity of hollow balloons made of a material selected
from thin-walled oxidizable and non-oxidizable material.
4. The explosive device of claim 1 wherein said particulate primary
solid component comprises a porous bed of solid particles which
includes a major effective quantity of oxidizing particles selected
from the alkali and alkaline earth metal nitrates, ammonium
nitrate, alkali and alkaline earth metal perchlorates, and ammonium
perchlorate; and a minor effective quantity of hollow ballons made
of a thin-walled non-oxidizable material, randomly distributed
through said bed.
5. The explosive device of claim 4 wherein said oxidizing particles
have a size smaller tha about 500 microns.
6. The explosive device of claim 5 wherein said hollow balloons
provide a void volume within said bed of sensitized paticulate
oxidizing particles of from about 0.3 to about 75 percent by volume
thereof.
7. The explosive device of claim 6 wherein said particulate primary
solid component comprises from about 0.1 to about 50 percent by
weight of said hollow balloons.
8. The explosive device of claim 7 wherein said hollow balloons
have a particle size within the range of from about 2 to about 400
microns.
9. The explosive device of claim 8 wherein said oxidizing particles
within said particulate primary solid component comprise ammonium
nitrate.
10. The explosive device of claim 8 wherein said particulate solid
secondary charge comprises particles of an oxidizing material
selected from alkali and alkaline earth metal nitrates, ammonium
nitrate, alkali and alkaline earth metal perchlorates, ammonium
perchlorate, and mixtures thereof.
11. The explosive device of claim 10 wherein the size of said
particles in said particulate secondary solid component is in the
range of from about 0.5 to about 10mm.
12. The explosive device of claim 11 wherein said particulate
secondary solid component comprises prilled ammonium nitrate.
13. The explosive device of claim 12 further comprising a liquid
component within the interstices of said primary and secondary
solid components.
14. The explosive device of claim 13 wherein said liquid component
comprises at least about 60 percent by weight nitromethane and up
to about 40 percent by weight of other liquids selected from
noncapsensitive liquid hydrocarbons having bonded nitrogen in the
positive valence state, and halogenated lower alkanes having from
about 1 to about 3 carbon atoms, and mixtures thereof.
15. The explosive device of claim 13 wherein said liquid component
comprises noncapsensitive hydrocarbon material containing nitrogen
in the positive valence state.
16. An explosive device which includes a particulate primary solid
component and a particulate secondary solid component which are
both activated by a liquid component comprising:
a. an elongated tubular having a first end and a second end with a
sealable opening for adding said liquid component positioned in the
first end thereof;
b. a bed comprising sensitized particulate material selected from
oxidizing and non-oxidizing material and having a particle size
smaller than about 3000 microns forming said particulate primary
solid component and positioned within said tubular container
adjacent the second end thereof;
c. a porous retaininng means which will pass said liquid component
but not said solid primary or secondary components, and separating
said particulate primary solid component from the remainder of the
enclosure within said container; and
d. a bed comprising solid particulate oxidizing material forming
said particulate secondary solid component and positioned within
said remainder of said cavity within said container.
17. The explosive device of claim 16 further comprising a cap well
means on said container positioned adjacent the second end
thereof.
18. The explosive device of claim 17 further comprisinng a sleeve
means for threadably engaging said second end.
19. The explosive device of claim 17 wherein the periphery of said
second end of said container carries first external screw threads
and said cap well means comprises an elongated longitudinal slot
forming an indentation transversely across said first external
screw threads.
20. The explosive device of claim 19 further comprising a sleeve
means for threadably engaging said first external screw
threads.
21. The explosive device of claim 20 further comprising second
external screw threads carried by the periphery of said first end
of said container.
22. The explosive device of claim 17 wherein said particulate
primary solid component comprises a porous bed of solid particles
which includes a major effective amount particulate non-oxidizing
particles selected from diatomaceous earth and expanded low density
silica having a minor effective amount of hollow balloons made of a
material selected from thin-walled oxidizable and non-oxidizable
materials randomly distributed therein.
23. The explosive device of claim 17 wherein said particulate
primary solid component comprises a porous bed of solid particles
which includes a major effective quantity of oxidizing particles
selected from the alkali and alkaline earth metal nitrates,
ammonium nitrate alkali and alkaline earth metal perchlorates, and
ammonium perchlorate; and a minor effective quantity of hollow
balloons made of a thin-walled non-oxidizable material, randomly
distributed through said bed.
24. The explosive device of claim 23 wherein said oxidizing
particles have a size smaller than about 500 microns.
25. The explosive device of claim 23 wherein said hollow balloons
provide a void wolume within said bed of sensitized particulate
oxidizing particles of from about 0.3 to about 75 percent by volume
thereof.
26. The explosive device of claim 25 wherein said particulate
primary solid component comprises from about 1 to about 50 percent
by weight of said hollow balloons.
27. The explosive device of claim 26 wherein said hollow balloons
have a particle size within the range of from about 2 to about 400
microns.
28. The explosive device of claim 27 wherein said oxidizing
particles within said particulate primary solid component comprise
ammonium nitrate.
29. The explosive device of claim 17 wherein said particulate solid
secondary charge comprises particles of an oxidizing material
selected from alkali and alkaline earth metal nitrates, ammonium
nitrate, alkali and alkaline earth metal perchlorates, ammonium
perchlorate, and mixtures thereof.
30. The explosive device of claim 29 wherein the size of said
particles in said particulate secondary solid component is in the
range of from about 0.5 to about 10mm.
31. The explosive device of claim 30 wherein said particulate
secondary solid component comprises prilled ammonium nitrate.
32. The explosive device of claim 30 further comprising a liquid
component within the interstices of said primary and secondary
solid components.
33. The explosive device of claim 32 wherein said liquid component
comprises at least about 60 percent by weight nitromethane and up
to about 40 percent by weight of other liquids selected from
noncap-sensitive liquid hydrocarbons having bonded nitrogen in the
positive valence state, and halogenated lower alkanes having from
about 1 to about 3 carbon atoms, and mixtures thereof.
34. The explosive device of claim 32 wherein said liquid component
comprises noncap-sensitive hydrocarbon material containing nitrogen
in the positive valence state.
35. An explosive device having a primary charge chamber and a
secondary charge chamber both armed by a liquid component
comprising:
a. a conatiner forming an enclosure for said primary charge chamber
and said secondary charge chamber;
b. a bed comprising sensitized particulate material armable by said
liquid component selected from oxidizing and non-oxidizing material
having a particle size smaller than about 3000 microns, positioned
within said primary charge chamber;
c. a porous retaining means positioned in said enclosure and
separating said primary charge chamber from said secondary charge
chamber, and which will pass said liquid component but not said
sensitized particulate material; and
d. a secondary charge chamber positioned in said enclosure on the
opposite side of said porous retaining means from said primary
charge chamber, and having at least one sealable opening through
said enclosure for adding said liquid component directly into said
secondary charge chamber.
36. The explosive device of claim 35 further comprising a capwell
means on said container positioned adjacent said primary charge
chamber.
37. The explosive device of claim 36 wherein said particulate
primary solid component comprises a porous bed of solid particles
which includes a major effective quantity of oxidizing particles
selected from the alkali and alkaline earth metal nitrates,
ammonium nitrate, alkali and alkaline earth metal perchlorates, and
ammonium perchlorate; and a minor effective quantity of hollow
balloons made of a thin-walled nonoxidizable material, randomly
distributed through said bed.
38. The explosive device of claim 37 wherein said oxidizing
particles have a size smaller than about 500 microns.
39. The explosive device of claim 37 wherein said hollow ballons
provide a void volume within said bed of sensitized particulate
oxidizing particles of from about 0.3 to about 75 percent by volume
thereof.
40. The explosive device of claim 39 wherein said particulate
primary solid component comprises from about 1.0 to about 50
percent by weight of said hollow balloons.
41. The explosive device of claim 41 wherein said hollow balloons
have a particle size within the range of from about 2 to about 400
microns.
42. The explosive device of claim 41 wherein said oxidizing
particles within said particulate primary solid component comprise
ammonium nitrate.
43. The explosive device of claim 41 further comprising a liquid
component in said remainder of said cavity and within the
interstices of said bed.
44. The explosive device of claim 43 wherein said liquid component
comprises at least about 75 percent by weight nitromethane and up
to about 25 percent by weight of other liquids selected from
noncapsensitive liquid hydrocarbons having bonded nitrogen in the
positive valence state, and halogenated lower alkanes having from 1
to about 3 carbon atoms, and mixtures thereof.
45. The explosive device of claim 41 wherein said liquid component
comprises a noncapsensitive liquid containing nitrogen in the
positive valence state.
46. The explosive device of claim 45 wherein said particulate
primary solid component comprises a porous bed of solid particles
which includes a major effective quantity of noonoxidizing
particles selected from diatomaceous earth and expanded low density
silica; and a minor effective quantity of hollow balloons made of a
material selected from thin-walled nonoxidizable and oxidizable
material, randomly distributed through said bed.
47. The explosive device of claim 46 wherein said oxidizing
particles have a size smaller than about 500 microns.
48. The explosive device of claim 46 wherein said hollow balloons
provide a void volume within said bed of sensitized particulate
nonoxidizing particles of from about 0.3 to about 75 percent by
volume thereof.
49. The explosive device of claim 48 wherein said particulate
primary solid component comprises from about 0.1 to about 50
percent by weight of said hollow balloons.
50. The explosive device of claim 49 wherein said hollow balloons
have a particle size within the range of from about 2 to about 400
microns.
51. The explosive device of claim 50 further comprising a liquid
component in said remainder of said cavity and within the
interstices of said bed.
52. The explosive device of claim 51 wherein said liquid component
comprises at least about 75 percent by weight nitromethane and up
to about 25 percent by weight of other liquids selected from
noncapsensitive liquid hydrocarbons having bonded nitrogen in the
positive valence state, and halogenated lower alkanes having from
about 1 to about 3 carbon atoms, and mixtures thereof.
53. The explosive device of claim 51 wherein said liquid component
comprises a noncapsensitive liquid containing nitrogen in the
positive valence state.
Description
This invention relates to explosives. In another aspect, this
invention relates to two-component liquid-solid based explosive
compositions. In still another aspect, this invention relates to a
novel device which includes solid primary and secondary components
for liquid-solid explosive compositions.
Explosive compositions such as used in seismic work, blasting in
bore holes, and ditching, such as underwater ditching, commonly
comprise a Class A explosive composition such as nitroglycerin,
dynamite, and the like. These compositions are easily detonated by
a low power blasting cap, but of course, require extreme caution
when being shipped, stored and utilized.
Many times, the Class A explosives are used as a primer or booster
charge for a main or secondary explosive charge such as a
relatively nonsensitive liquid-solid two-component explosive, e.g.,
ammonium nitrate-dinitrotoluene or ammonium nitrate-fuel oil
compositions. Thus, the typical two-component explosive composition
comprises a solid oxidizing material such as ammonium nitrate and a
liquid fuel such as fuel oil and/or a nitrogen containing
hydrocarbon material neither of which is classified as a Class A
explosive. Therefore, both components can be shipped separately in
ordinary commerce. The two components are generally admixed at the
site of use to create the explosive mixture. Examples of other
typical two-component explosive compoositions are set forth in U.S.
Pat. No. 2,892,377. Each of these two-component explosive
compositions is generally not very sensitive and cannot be
detonated by a No. 6 blasting cap and therefore, they generally
require a booster charge comprising a Class A explosive to detonate
the same.
Recently two improved liquid-solid two-component explosive
compositions have been devoloped. One such composition is set forth
in U.S. Pat. No. 3,718,512. This material comprises a first
component which includes a porous particulate solid component which
can comprise particles of either an oxidizing substance, such as
ammonium nitrate, or a non-oxidizing substance such as diatomaceous
earth, or mixtures thereof; and a liquid component such as
nitromethane which is sensitized when it is admixed with a solid
component. When the liquid component is admixed with a porous bed
of solid particles it is dispersed by capillary action, which
action inherently leaves void spaces throughout the mixture which
serves to sensitize the liquid component and make it detonable by a
No. 6 blasting cap. Another such improved two-component explosive
composition is set forth in U.S. Pat. No. 3,722,410 and comprises
ammonium nitrate prills which have been sensitized in such a manner
to make them uniquely porous and to have a density of less than
about 0.80 grams per cubic centimeter; and a liquid such as a
nitroalkane. This two-component explosive can also be detonated by
a No. 6 blasting cap. The solid and liquid components of the
above-described improved two-component explosive compositions can
be shipped separately in ordinary commerce because they are not
classified as Class A explosives.
Furthermore, the above-described improved two-component explosive
compositions have been utilized as boosters as primary charges for
ammonium nitrate-fuel oil secondary charges and the like. However,
in each instance, the two-component primary charge and the
two-component secondary charge must be individually mixed.
One object of this invention is to provide a novel explosive device
for a two-component liquid-solid explosive.
Another object of this invention is to provide a novel demolition
device which is detonable by a Number 6 blasting cap.
A further object of this invention is to provide a novel explosive
comprising a liquid-solid secondary explosive charge and an
improved liquid-solid booster charge.
A further object of this invention is to provide an explosive
device comprising an enclosure containing dissimilar primary and
secondary particulate solid components for a liquid solid explosive
which can be rapidly activated by a liquid which is added into the
enclosure.
According to the invention a novel explosive device is provided
which comprises an enclosure which contains an activated
particulate solid component for a liquid-solid primer explosive
separated by a porous member from a chamber for carrying a
secondary charge or charge component such as a particulate
oxidizing solid component for a secondary liquid-solid explosive
charge. Primer and secondary explosive charges are formed by
pouring an arming liquid such as a nitroalkane into the
enclosure.
According to a preferred embodiment of the subject invention a
demolition device is provided which comprises an elongated
cylindrical container having an enclosed first end and a sealable
opeining at its second end and a solid primary component positioned
within the first end comprising particles of an oxidizing material,
e.g., particles of ammonium nitrate having a size of less than
about 3000 microns, and having distributed therein from about
0.1-50% by weight of hollow balloons made of thin wall nonoxidizing
material, a porous member separating the primary solid component
from the portion of the container adjacent the second end thereof,
and with a secondary component positioned within said portion which
comprises particulate oxidizing solids such as prilled ammonium
nitrate. Preferably, a cap well means is positioned adjacent the
first end of the container and tubular sleeve means is provided for
engaging both the first and the second end of the container so that
several such containers can be connected in series.
This invention can be more easily understood from a study of the
drawings in which:
FIG. 1 is an exploded view of a preferred explosive device of the
subject invention:
FIG. 2 is a sectional view of the assembled explosive device shown
in FIG. 1;
FIG. 3 is a bottom plan view of the device of FIG. 2; and
FIG. 4 is a view of several explosive devices coupled together in
accordance with one embodiment of the subject invention.
Now referring to the drawings and specifically to FIG. 1, an
exploded view of explosive device 10 of the subject invention is
schematically shown. As shown, explosive device 10 comprises an
elongated tubular cylindrically shaped container 12 having an
enclosed first end 14 and an opening 16 through a narrowed neck 17
on the second end thereof. Screw threads 18 are carried on the
outer periphery of neck 17 and cooperate with the internal screw
threads 20 carried on the inner peripheral portion of cap 22.
Furthermore, the outside periphery of container 12 adjacent end 14
carries screw threads 24 as shown in the drawing. Also,
longitudinal cap slot 26 is positioned through screw threads 24 (to
form an indentation therein) adjacent end 14 in the manner shown in
the drawing. Furthermore, screw threads 28 are carried around the
periphery of the upper end of container 12. Sleeve 30 contains
screw threads 31 around the internal periphery thereof for engaging
screw threads 24 and/or 28. Explosive device 10 carries a solid
particulate booster or primary component for a liquid-solid booster
explosive composition within its interior adjacent longitudinal cap
slot 26. In addition, container 12 carries a solid particulate
component for a secondary or main liquid-solid explosive
composition in the upper portion thereof.
As shown in FIG. 2, the interior of container 12 is divided into a
lower primary charge chamber 32 and an upper secondary charge
chamber 34 by porous partition member 36. The primary charge
chamber 32 carries an activated particulate solid component 38 for
a liquid-solid explosive composition which functions as a booster
charge for explosive device 10. As shown, secondary charge chamber
34 carries a particulate solid component 40 for a liquid-solid
secondary or main charge for explosive device.
The particulate primary solid component 38 positioned within
primary charge chamber 32 is made of two sub-components. The first
sub-component comprises a comminuted particulate material, and the
second sub-component comprises thin-walled hollow balloons.
The comminuted solid sub-component of primary solid component 38
can comprise a noncap-sensitive inert or oxidizing material,
capable of being freely shipped in normal commerce. The primary
function of this sub-component is to provide a porous base or
substrate which is used to uniformly disperse the hollow balloons
and which will uniformly disperse the liquid component by gravity
and capillary action, thereby automatically providing an intimate
mixture of finely divided liquid component and void space. A second
function of providing additional energy through the reaction of an
oxidizing group with excess fuel portion in the liquid component
can be provided by an oxidizing solid component according to the
preferred embodiment of the subject invention. If an oxidizing
substrate contains potential gas forming elements in addition to
the elements of the oxidizing group a third function of the solid
component is to provide expandible gas capable of doing useful
work. Solid components usable within the scope of the present
invention are alkali and alkaline earth metal nitrates, ammonium
nitrate, alkali and alkaline earth metal perchlorates and ammonium
perchlorate, diatomaceous earth and expanded low density silica.
The solid particulate component used in the scope of this invention
has a particle size less than about 3000 microns, preferably less
than about 500 microns, and most preferably is in the range of from
about 5 to about 250 microns. The oxidizing particulate materials
used in the scope of the preferred embodiment of the subject
invention can be the alkali and alkaline earth metal nitrates,
ammonium nitrate, the alkali and alkaline earth metal perchlorates,
and ammonium perchlorate and mixtures thereof. The preferred such
materials include ammonium nitrate, sodium nitrate, and ammonium
perchlorate and mixtures thereof, with the most preferred being
ammonium nitrate.
The thin walled hollow balloons which can be used in the scope of
this invention generaly include the thin walled balloons or
microspheres made of glass, ceramic material, silica or resin.
Generally, the thin walled balloons can be made of any material
which is inert in the presence of the remaining constituents of the
composition. By "inert", such material should not constitute a fuel
for the oxidizing partiuclate material (if used therewith) and
also, should be stable in the presence of the liquid component used
in the scope of the subject invention. Generally, the thin walled
hollow balloons should have a particle size within the range of
from about 2 to about 400 microns. Any gas can be contained within
the hollow balloons.
Generally, from about 0.1 to about 50 percent by weight and more
preferably from about 0.5 to about 8 percent by weight of primary
solid component 38 made in accordance with the subject invention
will comprise the thin walled hollow balloons. Generally, the
thin-walled hollow balloons will provide a void volume of from
about 0.3 to 75 percent by volume of the total solids, preferably
about 0.8 to about 25 percent by volume of the total solids of the
explosive composition of the subject invention.
The thin-walled hollow balloons can be admixed with the comminuted
particulate material in any suitable way to obtain a random but
generally uniform distribution of the balloons therein. Suitable
methods include the mixing of two sub-components with a mixing
auger, or a ribbon blender, for example.
The hollow ballons which can be used only as a subcomponent with
the comminuted particulate material of non-oxidizing material in
primary solid component 38 can include the hollow oxidizable
microspheres made of resin. Suitable such resin balloons which can
be used in the scope of the present invention are water insoluble
and nitromethane insoluble, thin-walled, hollow, spherical balloons
of a polymerized thermosetting resin selected from the group
consisting of urea-formaldehyde and phenolformaldehyde. The resin
balloons are of low density and small particle size. Typical resin
balloons have a bulk density of less than 0.5 gr./cc. and a
diameter of from about 2 to about 360 microns. Resin balloons are
more fully described in U.S. Pat. No. 3,010,288 to Coursen et al
issued Aug. 20, 1963, which patent is hereby incorporated by
reference into this application.
Suitable hollow balloons made of thin-walled non-oxidizable
material which can be used in the preferred embodiment of the
subject invention within primary solid component 38 include hollow
balloons sold under the trademarks of "ECCOSPHERES" and
"MICROBALLOONS" by Emerson and Cuming, Inc., Canton, Massachusetts,
or 3M brand glass bubbles sold by 3M Company, St. Paul, Minnesota
and can include the microspheres which are made of sodium
borosilicate glass, silica, insoluble glass, and ceramic material.
These thin-walled balloons are basically free flowing, thin-walled,
hollow, glass or ceramic spheres which have a particle size of from
about 10 to about 300 microns. These spheres have an average wall
thickness from about 1.0 microns and generally, from about 1.5 to
about 2 microns. Furthermore, the spherical hollow particles are
hole-free, nonflammable, and have a low thermal conductivity, a
high melting point, are readily wetted, and have a low dielectric
constant. Suitable nonoxidizable thin-walled hollow balloons
comprise about 40 weight percent therof having a particle size in
the range of from about 60 to about 100 microns with the majority
of the remaining balloons having a particle size of 100 microns or
greater.
Particulate secondary solid component 40 comprises particles of
oxidizing material generally larger in size than those of the
primary solid component 38. Suitable such oxidizing materials
include particles selected from alkali and alkaline earth metal
nitrates, ammonium nitrate, alkali and alkaline earth metal
perchlorates, ammonium perchlorate, and mixtures thereof. Again,
the preferred oxidizing materials include ammonium nitrate, sodium
nitrate, and ammonium perchlorate and mixtures thereof, with the
most preferred being ammonium nitrate. The particle size of the
particulate materials used within secondary solid component 40 can
be selected depending on the arming rate which is desired. For
example, the larger particle sizes will result in a faster arming
rate for explosive device 10. Suitable particle sizes can be in the
range of from about 0.5mm to about 10mm and preferably about 2mm.
The most preferred materials utilized are commercially prilled
materials such as prilled ammonium nitrate which is commonly sold
as a fertilizer. In addition, if desired, the activated ammonium
nitrate prills which are disclosed in said U.S. Pat. No. 3,722,410
can be used in the scope of this invention as a part of all of the
particulate solids used within secondary solid component 40 and
such patent is herein incorporated by reference into this
application. Furthermore, if desired, the particulate secondary
solid component 40 can contain up to 2 percent by weight of the
hollow balloons made of a thin-walled nonoxidizable material which
are described above. In such instance, the hollow ballons are
thoroughly admixed within the particulate oxidizing material so
that a random but uniform distribution thereof results therein.
The relative quantity of primary solid component 38 to secondary
solid component 40 can vary with the particular device. Generally,
sufficient primary solid component 38 must be present which, when
combined with a liquid component and detonated by a blasting cap
will also detonate the secondary liquid-solid charge. Generally,
primary solid component 38 comprises from about 1/6 to about 1/3 of
the volume of the secondary solid component 40.
Furthermore, in accordance with a lesser preferred embodiment of
the subject invention, solid component 40 is not utilized. In this
embodiment, secondary charge chamber 34 can be partially or
completely filled with a detonable liquid component, and the
primary liquid-solid charge is utilized as a primer charge
therefor.
Container 12, cap 22 and sleeve 30 are preferably made of a plastic
material such as a polyolefin, e.g., high density polyethylene, and
can be easily molded. Porous partition member 36 is preferably made
of a flexible open cell polymeric foam, e.g., an open cell
polyurethane foam and preferably takes the form of a thin disc or a
short cylinder. It is noted that any other suitable porous means
can be utilized to separate primary solid component 38 from the
remainder of the enclosure within container 12. For example a
porous bag such as made of woven fibers can be utilized to contain
solid component 38. The porosity of porous partition member 36
should be such that it effectively separates the primary solid
component 38 and secondary solid component 40, but yet will allow
the liquid which is used in the scope of the invention to pass
therethrough.
In the manufacture of explosive device 10, container 12, screw cap
22 and sleeve 30 are molded by conventional molding techniques;
thereafter, the particulate primary solid charge component 38 is
formed and poured through opening 16. Thereafter, the porous
flexible partition member 36 is compressed and passed through
opening 16 and then placed upon the top of particulate primary
solid component 38. Thereafter, if desired, particulate secondary
solid component 40 is passed through opening 16 and screw cap 18 is
threadably engaged with screw threads 18 on neck 17. Sleeve 30 is
threadably engaged upon screw threads 24 of explosive device 10.
When assembled, the explosive 10 can be shipped in ordinary
commerce and is not a Class A explosive. In essence, neither of the
solid particulate components 38 or 40 are cap-detonable. An
explosive composition is formed by merely pouring a liquid
component through opening 16 which serves as the liquid component
for primary solid component 38 and secondary solid component
40.
Suitable detonable, but noncap-sensitive liquids which can be used
as the liquid component in the scope of the subject invention
include noncap-sensitive liquid hydrocarbon material containing
bonded nitrogen in a positive valence state. Typical compounds of
this class of materials are the nitro and nitrated hydrocarbonss.
Exemplary materials which can be utilized within the scope of the
present invention include nitroaliphatic hydrocarbons,
nitroaromatic hydrocarbons, aliphatic nitrates, nitramines and
mixtures thereof. Preferable liquid components include the
nitroalkane compounds containing 3 or less carbon atoms and
mixtures of the lower aromatic compounds, e.g., nitromethane and
the dinitrotoluene oils.
An example of a non-detonable liquid component which becomes
detonable and cap-sensitive when admixed with the solid component
comprises hydrazine when admixed with a solid nitrate.
The liquid component which is utilized to arm the primary and
secondary solid components 38 and 40 within explosive device 10
within the preferred embodiment of the subject invention comprises
a nitroalkane. Preferably, the liquid component comprises from
about 60 to about 100 percent by weight of nitromethane. The
nitromethane can be admixed with up to 40 weight percent of other
noncap-sensitive liquid hydrocarbons having bonded nitorgen in the
positive valence state and halogenated lower alkanes having from
about 1 to about 3 carbon atoms.
Exemplary materials which can be used with the nitromethane in the
liquid component in the preferred embodiment of the subject
invention include nitroaliphatic hydrocarbons, nitroaromatic
hydrocarbons, aliphatic nitrates, nitramines, trichloroethylene,
tetrachloroethylene, carbon tetrachloride, and the like, and
mixtures thereof. Preferably, the liquid materials which can be
used with the nitromethane include nitroalkane compounds having
from 2 to 3 carbon atoms and lower nitoraromatic compounds and
mixtures thereof. The presence of halogenated compounds in the
liquid mixture can serve to lower the flashpoint of the
nitromethane.
Again referring to the preferred embodiment set forth in the
drawing, to convert explosive device 10 into an explosive charge,
with explosive device 10 in the upright position, cap 22 is removed
from neck 17, and the liquid component is poured through opening
16. The liquid component will pass downwardly through particulate
solid secondary component 40, within secondary charge chamber 34,
through porous partition member 36 and into primary charge chamber
32 containing primary solid component 38. Generally, sufficient
liquid component is utilized in the scope of the subject invention
to saturate the primary solid component 38 (i.e., fill the
interstitial void spaces therewithin), and to provide at least an
oxygen balancing amount of fuel for secondary solid component 40.
Generally, the liquid component will comprise from about 6 to 60
percent by weight of the total primary charge and from about 6 to
100 percent by weight of the total secondary charge. It is
generally preferred that sufficient liquid component be utilized to
fill the interstitial space with both solid components.
After the explosive composition has been formed by admixing the
liquid component with the solid components within explosive device
10, a blasting cap at least as powerful as a Number 6 blasting cap
can be placed within capwell 42, which is formed by the cooperation
of longitudinal cap slot 26 and sleeve 30 as shown in FIG. 3. A
Number 6 blasting cap will be sufficient to detonate the explosive
device 10. The detonation of the blasting cap will fire the
liquid-solid explosive within primary charge chamber 32 which will
in turn propagate the explosion and detonate the liquid-solid
explosive mixture within secondary charge chamber 34.
When armed with the liquid component, explosive device 10 can be
used as a single unit or can be coupled with other explosive device
units 10 as shown in FIG. 4. As illustrated, the screw threads 28
of a first explosive device 10a can be threadably engaged with the
screw threads 31 of a second explosive device 10b to form a column
of explosives. After a sufficient number of explosive devices 10
have been coupled together in a manner schematically illustrated in
FIG. 4, a blasting cap 44 can be positioned within cap well 42 of
demolition device 10a and the entire column detonated. The
detonation of explosive device 10a will propagate the explosion to
explosive device 10b and successive such devices. This arrangement
whereby the primer charges are staggered assure complete detonation
of the entire explosives column.
In addition, it must be noted that explosive device 10 can be
utilized according to the lesser preferred embodiment of the
subject invention by omitting secondary solid component 40 from
secondary charge chamber 34. In this instance the liquid component
is used to fill the interstices of primary solid component 38
within primary charge chamber 32, and also fill all or part of
secondary charge chamber 34. When operating in accordance with this
embodiment, the liquid component should comprise a detonable
liquid. In this instance, the most preferred liquid component
comprises at least about 75% by weight or nitromethane, and up to
25% by weight of the liquid component can comprise the other
liquids disclosed above.
Explosive device 10 can be conveniently utilized in seismic
exploration work, explosive operations within bore holes, or
ditching. Furthermore, explosive device 10 can be used in
underwater demolition operations such as undersea ditching. Once
each explosive device 10 is armed with a liquid it can be placed in
a demolition site for an indefinite period of time before it is
detonated. Furthermore, the explosive device 10 of the subject
invention which has been armed with a liquid component can be
subjected to rather severe forces which would tend to compact the
particulate solid components 38 and 40 but yet not deleteriously
affect the explosive. Furthermore, the explosive device 10 when
armed with a liquid can be detonated under relatively high
pressure, such as hydrostatic pressure under a body of water.
While this invention has been described in relation to its
preferred embodiments, it is to be understood that various
modifications thereof will now be apparent to one skilled in the
art upon reading this specification and it is intended to cover
such modifications as fall within the scope of the appended
claims.
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