Патент USA US2136205

Patented Nov. 8, 1938
2,136,205
UNETED STATES PATNT OFFCE
.
2,136,205
BLASTING POWDER
Land 8. Byers, Glendale, Calif.
No Drawing. Application November 15, 1937,
Serial No. 174,694
3 Claims. (C1. 52-11)
This invention relates to blasting powder and ably in the form of a ?ne spray to form a slightly
has for its object an improvement in explosive
compositions suitable for general blasting pur
poses which will have important advantages over
i
black powder.
,
Among the advantages of my improved powder
over blasting powder may be mentioned a lesser
density with same heave or moving power, greater
rate of decomposition upon explosion, more re
0 sistant to water or moisture, much less subject
to ignition from shock or friction, not subject
to ignition from contact with ordinary ?ame, no
poisonous fumes, and with all cheaper and quicker
_ to manufacture.
>
Briefly described my improved blasting powder
may be said to comprise a loose mass of sodium
nitrate kernels, each of which is entirely en
veloped by an adherent layer of explosive agents
adapted to form a substantially balanced forti?ed
) and sensitized entity complete itself, and exhibit
ing all of the characteristics above enumerated.
My improved blasting powder consists of the
following ingredients:
sticky film of this explosive material about each
pellet of the nitrate.
-
As soon as the nitrate pellets are evenly coated
the previously ?nely powdered and intimately 5
mixed remaining ingredients are dusted in while
the rolling is continued until each individual
sodium nitrate pellet is completely enveloped and
enclosed in a layer of the thoroughly mixed pow
dered ingredients evenly distributed thereover, 1.0
and bound thereto so as to form a substantially
dry granular mass each grain of which is a‘ com
plete explosive unit.
‘
The coating of the nitrate pellets as described
should be carried out at a temperature sufficiently 15
above the setting point of the particular liquifiable
nitro body being used so that this binding agent
will remain in ?uid condition until the comple
tion of the coating operation.
Instead of the particular nitro bodies set out, 20
others such as the nitro glycerine, benzenes,
naphthalenes, etc. may be used, but those given
in the formula are preferred.
Percent by weight
5 Pelleted sodium nitrate ____________ __
90 to
A liquid nitro body (liqui?able at mod-
.
crate temperatures) _____________ __
3 to
80
6
Ammonium nitrate ______________ __'__
3 to
6
Potassium perchlorate _____________ __
3* Powdered aluminum _______________ __
3 to
l to
6
2
Also, the speci?c nitrate or perchlorate and
oxidizable metal used as the coating layer may 25
be varied within the knowledge of explosive en
gineers, but after my experiments I feel that the
above simple formula will meet all requirements
in a blasting powder of this kind, though any such
modi?cations as suggested- are intended to be 30
included in the scope of my appended claims.
100
100
Powdered carbon may also be incorporated in
. an amount from 1/_>% to 3% and will increase
somewhat the work-energy as well as improve the
oxygen balance, but is not necessary to produce
combustion in the explosive composition. Also
a suitable antiacid may be added.
The pelleted sodium nitrate should be more or
less round in form and of substantially uniform
mesh size as per following examples:
' I am aware of pelleted nitrate of sodium as such
being used in explosives of the dynamite class,
also the coating of ammonium nitrate pellets
with trimethylal-ethyl-methane-trinitrate, and 35
also with other substances, but I am not aware of
a blasting powder being heretofore produced in
which each granule is a complete explosive unit
in itself formed of a central kernel of sodium
nitrate entirely enclosed in the fortifying, sen- 40
sitizing and ?ame supporting agents in even
dissemination and in adherent relation about its
(1) Minus 6 mesh, plus 8 mesh
surface in proportions to make of each a sub
(2) Minus 8 mesh, plus 10 mesh ‘
stantially balanced explosive unit. Nor do I know
(3) Minus 10 mesh, plus 12 mesh,
of any comparable powder no matter of what 45
constituted which has all of the valuable prop
erties in comparison with black powder, as above
set out.
Percussion tests of my improved blasting pow
der as above described, made under Bureau of 50
and so on up to minus 36 mesh, plus 40 mesh. -
The ?ner mesh pellets are employed where in
creased rate of combustion or greater brisance
in the blasting powder is desired, and vice versa.
This pelleted sodium nitrate is placed in a suit
able tumbler or inclined rotating pellet coating
bowl, and while under rotation the liquid nitro
body (preferably D. N. T. or M. N. T., T. N. T.)
is added to the revolving and rolling mass, prefer~
Explosives’ requirements, “Falling weight test,”
gave zero results with the 8 pound weight and 7
inch drop (steel on steel anvil) and actually re
quired in excess of a 12 inch drop before explosion
could be induced.
55
2
araaecs
Similarly, frictional impact tests as per Bureau
of Mines’ requirements “Anvil friction test,” both
with the ?ber and steel shoe, produced neither
explosion, nor ignition-in fact no distinguish
able crackling, and furthermore Bureau of Mines’
tests for fumes reported “Poisonous fumes nil.”
The safety of my improved blasting powder
over black powder is particularly outstanding in
ignition tests, for not only‘ does the improved
10 powder withstand ignition from ordinary ?ame
contact, such for instance as burning a box of
matches on top of a pile of it, but it will not
ignite if a teaspoonful of black powder is placed
on top of a pile of it and the black powder
15 ignited.
Having thus described my improved blasting
composition, what I claim is:
1. A blasting powder comprising a loose mass
of pellets having a sodium nitrate center coated
20 with a viscous ?lm of an explosive nitric ester
lique?able at moderate temperatures forming a
\binder holding an outer layer of an intimate mix
ture of powdered ammonium nitrate, potassium
perchlorate and powdered aluminum, so as to
make each pellet a complete explosive unit.
2. A blasting powder comprising a loose mass of
pellets having a sodium nitrate center coated with
.a. viscous ?lm of an explosive nitric ester lique
?able at moderate temperature forming a binder
holding anrouter layer of an intimate mixture
of a ?nely divided explosive including a nitrate
salt, a perchlorate, and an easily oxidizable metal.
3. A blasting powder comprising a loose mass
of substantially uniform size pellets having a
sodium nitrate center coated with a viscous ?lm of
an explosive nitric ester lique?able at moderate
, temperatures forming a binder holding an outer
layer of an intimate mixture of a ?nely divided
explosive including an oxygen yielding salt, and
an easily oxidizable metal.
,
LAUD S. BYERS.
20