Note: Descriptions are shown in the official language in which they were submitted.
3 1 ~052
BACKGROUND OF THE INVENTION
Field of the Invention
This invention relàtes to a poly- or multi-base-propellant
charge powder for tubular weapons and missiles with
nitro-cellulose, blasting oils, and optionally other
nitro compounds as energy carriers.
Desciption of the Prior Art_
The purpose of the blasting oil in multi-bas~
propellant charge powders of this type is to increase the
energy content of the propellant charge powder, which is
characterised by the heat of explosion, above a value
which can be reached by using so-called mono base powders
consisting substantially only of nitrocellulose. The value
of the heat of explosion corresponds in practical terms to
the energy content of the nitrocellulose itself (eg approx.
4000 j!g). In addition, the blasting oil is used as a
gelatinator for nitrocellulose. Occasionally, oils which
) are used to cause the nitrocellulose to gelatinate, but
which have an energy content of less or at best equal to
that of the lowest nitrated nitrocellulose, which is still
used for powders, are not called blasting oils because of
the energy increase which is aimed for.
The following alcohol nitrates are technically
important blasting oils in the above sense:
25 Nitroglycerine tH2 ~ ~ NO2 heat of explosion
(= NGL) CH - ~ NO2 6322 J/g
CH2 - - NO2 oxygen value + 3.5
.~, . . .
.~
~ ~ 6805~
.
Diethylene glycol CH2 - 0 - N02 heat of explosion
dinitrate CH2 4~57 J/g
(= ~iglycol dinitrate CH2 oxygen value - 40.8
5 = DEGN) CH2 ~ ~ NO2
' ' '
1,2,4-butane triol CH2 ~ ~ NO2 hea~ of explosion
trinitrate CH2 5945 J/g
CH2 - 0 - N02 oxygen value -16.6
2 N 2
.
10 Methriol trinitrate CH2 - 0 - N02 heat of explosion
3 I CH2 0 - N02 5175 J/g
CH2 ~ 0 - N02 oxygen value -34.5 %
Conventlonal propellant charge powders contain
a single blasting oil. The blasting oil ~sed in any
particular formulation, its content, the nitro-cellulose
content and its degree of nitration determine the properties
of the propellant charge powder and its behaviour during
production. The typical degree of nitration lying
between 11.8 and 1~.4 ~ N2 therefore influences the
production process and the energy content of the propellant
charge powder. l~his applies to a greater extent for the
blasting oil which is used in any particular case.
Since the blasting oils differ, for example, in
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~ 3 ~052
the gelling behaviour relative to the nitrocellulose,
the heat of explosion and the oxygen value, propellant
charge powders having different properties can therefore
be produced from them.
The propellant charge powders which are richest
in energy are obtained by using nitroglycerine. Thus,.
for example, a double-base propellant cha~ge powder produced
with solvent with about 40 ~ of nitroglycerine can be
- ~ adjusted to a heat of expiosion of 5,000 j/g. On the
other hand, a comparable propellant;charge powder with
diglycol dinitrate produces a heat of explosion of .
42~0 J/g~
Taking into consideration the production process
~or a propellant charge powder, the heat of explosion
thereof is virtually unable to rise beyond a specific
value which is dependent on the blasting oil used at any
time. Thus, for example, it ls impossible, wlthout the
.. use of solvents, to produce a propellant charge powder
containing diglycol dinitrate as blasting oil and having
20 a heat of explosion of 4750 J~y. In the past, it was
normalin such cases to adjust the.heat of explosion
reguired by using a higher calorific oil, i.e. nitro-
glycerine in the example above, and by simultaneously
incorporating energy consuming matexials such as, for
example, centralite or phthalates. It is necessary
to use energy-consuming materials because propellant
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I ~1 6~52
charge powder demands a specific minimum quantity of
blasting oil, i.e. nitroglycerine in the example, for
reasons of production, for example its homogenisation and
gelatination on hot rolling mills. However, this minimum.
quantity of blasting oil would result in exceeding the
required heat of e~plosion if energy-consuming materials
were not used. On the other hand, the energy-consuming
.. ~ material in the propellant.charge powder can be ballast
. for the actual operation thereof, which can adversely
affect desired properties of the propellant charge powder
under certain circumstances.
The known tri-base propelLant charge powders, for
example.nitroguanidinè~containing nitroglycerine powder
or nitroguanidine-containing diglycol dinitrate powder,
known as gudol powder, also contain only one blasting oil
each. When using these tri-base propellant charge powders,
it is not therefore possible to adjust a heat of explosion
.~ which is predetermined as desired within a considerable
range ~ithout energy-consuming materials. The other
energy carrier contained in tri-base propellant charge
powders, for example nitroguanidine, cannot be used for
such adjustment because it does not induce gelatination
but instead is a filler which can be incorporated lnto the
nLtrocellulose blastlng oil gel only to a limited extent.
. SUMMARY OF THE INVENTION
An object of the invention is to provide a new
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multi-base propellant charge powder. This powder should,
in particular, be adjustable within a wide energy range to
a desired hea-t of explosion, be easy to produce and, in
addition, also be further improved in its other properties,
in particular in its blasting behaviour and its storage
ability compared to conventional propellant charge powders.
I'he invention thus provides a multi-base propellant
charge powder which contains two or more different blasting
oils instead of the conventionally used sinyle, chemically
uniform blasting oil.
In accordance with the present invention there is
provided a multi-base propellant charge powder for tubular
weapons and missiles having a specific, predetermined heat
of explosion, comprising nitrocellulose and at least two
different blasting oils selected from the group consisting
of nitroglycerine, diglycol dinitrate, methriol trinitrate
and 1,2,~-butane-triol trinitrate, wherein:
(a) the propellant charge powder is made in
a production process without the use of solvents and the
total blasting oil content is determined with regard to
optimum homogenization and gelatination in the production
process, the total blasting oil content amounting at most
to 100% by weight, based on the content of nitrocellulose;
and wherein
(b) the proportion of higher calorific blasting
oils in the total blasting oil content is chosen to produce
the specific, predetermined heat of explosion.
In accordance with the present invention there is
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~ 3 681)5Z
further provlded a method of producing a multi-base
propellant charge powder for tubular weapons and missiles
having a specific, predetermined heat of explosion, com-
prising the steps of:
(a ? mixing together the components of a raw
mixture comprising nitrocellulose and at least two different
blasting oils selected from the group consisting of nitro-
glycerine, diglycol dinitrate, methriol trinitrate and
1,2,4-butane-triol trinitrate. The total blasting oil con-
tent being determined with regard to optimum homogenization
and gelatination of the mixture and amounting at most to
100% by weight based on the nitrocellulose content. The
higher calorific blasting oils in the total blasting oil
content being chosen to produce the specific heat of ex-
plosion;
(b) pressing the gelatinized mixture through a
die into strands of the desired diameter for use as a
propellant charge in ammunition.
DETAILED DESCRIPTION OF THE INVENTION
With the propellant charge powder according to
the invention, it is possible in a surprisingly simple way
to adjust precisely a specific, predetermined heat of
explosion without using energy-consuming materials merely by
suitable variation of the proportions of the at least two
different blasting oils, which also differ in their energy
content. The adaptability resulting from the incorporation
of two or more blasting oils allows the precise adjustment
of a required heat of explosion, even taking into
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I ~ 68052
consideration limits for the composition which are brought
about by the production procedure, and taking into
consideration other properties which are to be demanded
of a propellant charge powder.
Blasting oils which are preferably used for the
propellant charge powder according to the invention are
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~ ` I 16~05Z
nitroglycerine, diglycol dinitrate, methriol trinitrate
and 1,2,4-butanetriol trinitrate. With the propellant
charge powder according to the invention, it is preferred
that the proportion of higher calorific blasting oils in
the total blasting oil content is calculated in such a way
that a specific, predetermined explosion heat is obtained
without energy-consuming ballast materials such as phthalates
- or centralites. It is thus advantageous to make the content
of lower calorific blasting oils as large as possible and
to incorporate higher caloriflc blasting oils into the
propellant charge powder only in the quantity needed for
obtaining the required heat of explosion, within the limits
for the total blasting oil content. The lower limit is
generally based on the production process and the upper limit
on the properties of the powder. The bonding behaviour,
for example, of the blasting oils is also considered with
respect to the risk of exudation.
-~ The propellant charge powder according to the
invention may be produced solvent-free (solventless
~ procedure~, for example on rolling mills and/or extruders.
The total blasting oil content is preferably determined
with règard to optimum homogenization and qelatination
in the production process. The total blasting oil-content
in this embodiment generally amounts to at most 100 ~ by
weight, preferably between 54 % by weight and 82 ~ by
weight! based on ~he content of nitrocellulose. The powder
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- I 1 68~52
generally contains approximately 33-52 ~ by weight
diglycol dinitrate, preferably 41-43 ~ by weight diglycol
dinitrate, and approximately 21-30 ~ by weight nitro-
glycerine, preferably 24-26 ~ by weight nitroglycerine.
The propellant charge powder may be produced as a
double-base or triple-base powder with a limited addition
of solvent as gelatination agent (semi-solvent procedure) J
and the total blasting oil content in this case preferably
amounts to up to 30 ~ by weight.
The propellant charge powder may also be produced
by a conventional solvent process (solvent procedure),
in which the total blasting oil content is determined
in each case with regard to the heat of explosion to be
adjusted and/or the proportion of nitroguanidine or
nitramine to be incorporated. In this case the total
blasting oil content is preferably`determined in such a
way that up to 55 ~ by weight of nitroguanidine or nitra-
mines such as hexogen or octogen can ~e incorporated into the
nitrocellulose blasting oil gel. The total blasting oil
content preferably amounts to up ~o 150 ~ by weight,
based on the nitrocellulose content.
The advantageous adjustability of the heat of
.
explosion in a propellant charge powder according to the
invention is demonstrated by the ~ollowing comparison:
A conventional propellant charge powder A has the
.
following composition:
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I 1 68052
.
Nitrocellulose with 13.1 ~ N252.00 ~ by weight
Nitroglycerine 40.00 ~ by weight
Plasticisers
5.50 ~ by welght
Stabilisers . . 2.50_% by weiqht
~00.00 ~ by weight
The heat of explosion amounts to about 4600 J/g.
A different conventional propellant charge powder
B has the following composition:.
: Nitrocellulose with 12.6 ~ N256.00 ~ by weight
10 Nitroglycerine .38.80 % by weight.
- Stabilisers 5.10 ~ by weight
Magnesium oxide + Graphite0.10 ~_~y weiqht
100.00 % by weight
The heat of explosion amounts to about 4,600 J~g.
A propellant charge powder C according to the
invention has the following composition
Nitrocellulose with 13.0 ~ N259.50 % by weight
Diglycol dinitrate24.80 ~ by weight
Nitroglycerine 14.90 ~ by weight
20 Stabilisers 0.70 ~ by weight
Magnesium oxide + Graphite0.10 ~ by weight
. 100.00 % by weight
The heat of explosion again amounts to about 4l600
Joule~g.
The propellant charge powders A and B contain
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l l 6gos2
a much higher proportion of stabilisers and plasticisers
and of stabilisers, respectively, than necessary. The
excess proportion serves only to consume the energy, ~y
means of which the heat of explosion is adjusted to the
value indicated. With the propellant charge powder C
according to the invention, however, the same explosion
heat is obtained without special energy consumption by the
incorporation of two blastlng oils in suitable proportions.
In order to compare the properties of the powders,
o ~ the propellant charge powders B and C were inserted in a -
105 mm calibre weapon~ In this process, it was found
that the propellant charge powder C according to the
invention has a much more ~avourable external temperature-
pressure behaviour than the propellant charge powder B.
The propellant charge powder B demonstrated a rise in
pressure which should be judged as critical at only -40C,
but this did not occur under otherwise identical conditions
with the propellant charge powder C.
The blasting properties of the propellant charge
powders A and C were compared with a 120 mm calibre
weapon. It was found that the propellar.t charge powder
C according to the invention prod~ced blasting rates
which were only achieved by the propellant charge powder
A at pressures which were 100 to 200 bar higher.
The propellant charge powder according to the
invention with several blasting oils is therefore of
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1 1 ~gO52
clear ballistic superiority relative to conventional
propellant charge powders.
The propellant charge powder according to the
invention exhibits another advantageous property:
Combustible cartridge shells are being used
more and more in modern weapon systems instead of the
conventional metal cartridges. They consist, for example,
~` of a high proportion of nitrocelluloses and additional
neutral fibres, a resin binder and a chemical stabiliser
for the nitrocellulose. Owing to their material
compositionr they can absorb softeners and blasting oils
in contact with propellant charge powders. However, in
- order to guarantee that ammunition with combustible
casings can be stored for a long time, it is important
that the propellant charge powder releases a minimum amount
of blasting oil into the casing material.
Examination of the propellant charge powder
according to the invention in this respect surprisingly
revealed that it releases considerably less polyalcohol
nitrate into combustible casing material than conventional
propellant charge powders.
In particular, an investigation was carried out
with the above-mentioned propellan~ charge powders A and
C by pressing propellant charge powder between two pieces
~ combustible casing material and storing it in well
sealed bottles at 65C and 80C. 'l'he increase in the
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1 1 6~3052
weight of the combustible casing material was followed
over a period of time.
At 80C storage temperature, the following
increases in weight were determined.
Powder A Powder C Difference
After one week 9.0 ~ 7.3 ~ 1.7 %
After three weeks 16.7 ~ 12.0 ~ 4.7 ~
~j After six weeks 21.4 % 14.5 ~ 6.9 %
- At 65C storage temperature, the following
.
increase in weight was determined after 18 days:
Powder A Powder C Difference
8.0 % ~.9 ~
The results listed above clearly demonstrate the
superiority of a propellant charge powder according to the
invention over a conventional propellant charge powder with !
regard to the migration of the blasting oil into the casing
material.
Finally r the additional advantage of comparatively
slight erosion of the barrel of the weapon can be
expected in the case of a propellant charge powder according
to the invention owing to the precise adjustability of the
- heat of explosion.
Four embodiments of the propellant charge powder
according to the invention are described in more detail
below.
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I 1 68052
Example 1
A solvent-free diglycol dinitrate/nitroglycerine
propellant charge powder was produced as follows:
148.8 kg Dry weight of a 30 ~ water-containing
pulverulent raw mixture having the following
composition, based on dry we1ght:
60 % Nitrocellulose having a degree of
,~ nitration of l3.0 ~ nitrogen
25 % Diglycol dinitrate
15 % Nitroglycerlne:
l.080 kg Akardit II
- 0.074 kg Magnesium oxide
0.075 kg Graphite
are mixed together in a 400 l kneader of the type
lS conventionally used in powder production.
After optimum thorough mixing in the kneader, the
mixture is worked on ~ roller kneading mechanism at 85~C
to a thoroughly gelatinised sheet in the conventional
way, then rolled into a press roll and pressed in a
hydraulic press at 70~' to a 7~hole strand whose diameter
and web width are adjusted to the requirements of the
ammunition. A~ter cutting the strands to the required
length, the powder is mixed after storage to ripen.
The finished powder has the following composition
within the limits of tolerance:
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~ 1 fi805Z
Nitrocellulose with 13.0 ~ nitrogen 59.5 ~ by weight
Diglycol dinitrate 24.~ ~ by weight
Nitroglycerine 14.9 ~ by weight
Akardit II 0.7 ~ by weight
5 Graphite U.05 % by weight
Magnesium oxide . 0.05 ~ by weiqht
100 . 00 96 by welght
~) . Its heat of explosion amounts to about 4,600 J/g.
The desirable ballistic behaviour described above
1~ was observed in the propellant charge powder.
Examp.le_2
.
A solvent~free butanetriol trinitrate/nitroglycerine
propellant charge powder was produced as follows:
The kneading mixture is as follows:
148.8 kg Dry weight o~ a 30 ~ water-containing raw
powder mixture haviny the following composition,
based on dry weight:
64 ~ Nitrocellulose having a degree of nitration
o~ 13~0 ~ nitrogen,
22 ~ 1,2,4-butanetriol trlnitrate,
14 ~ Nitroglycerine,
0.375 kg Centralit I
0.6~5 kg Akardit II
0.075 kg Magnesium oxide
25 0.075 kg Graphite.
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1 1 68052
The production corresponds to Example 1.
The finished powder has the following composition
within the limits of tolerance:
Nitrocellulose with 13.0 ~ nitrogen Ç3.50 % by
. weight
1,2,4-butanetriol trinitrate .21.70 ~ by
weight
Nitroglycerine . 14.00 ~ by
-weight
10 Centralit I U.25 ~ by
weight
Akardit II 0.45 % by
- weight
Graphite . 0.05 % by
weight
Magnesium oxide O.U5 % by
weiqht
. 100.00 % by ~ :
. weight.
Its heat of explosion amounts to about 4950 JJg.
Example 3
A solvent-free diglycol dinitrate/nitroglycerine~
nitroguanidine propellant charge powder was produced as ~.
follows:
The kneading mixture is as follows: .
103.8 kg Dry weight of a 30 % water-containing
pulverulent raw mixture analogous to E~ample
2, having diglycoI dinitrate instead of l,2,4
butanetriol trinitrate
1 1 6~3052
,
~45.0 kg Nitroguanidine
- 0.300 kg Centralit I
0.750 kg Akardit II
0.075 kg Magnesium oxide
0.075 kg Graphite
- The production corresponds to Example 1.
The finished powder has the following composition
-j within the limlts of tolerance:
.~ J ~ .
Nitrocellylose with 13.0 ~ nitrogen 44.30.% by weight
10 Diglycol dinitrate L5 . OO % by weight
Nitroglycerine .9.90 % by weight
Nitroguanidine 30.00 %. by weight
Centralit I 0.20 ~ by weight
Akardit II O.S0 ~ by weight
Magnesium oxide 0.05 % by weight
GraphIte 0.05 % by weight
. 100.00 % by weight
) Its heat of explosion amounts to about 4,100 J/g.
Exam
` 20 A solvent-containing butanetriol trinitrate~
methriol trinitrate/diglycol dinitrate/nitroguanidine
propellant charge powder was produced as follows:
172 kg of a 30 % alcohol-containing nitrocellulose with
12~8 ~ N2 t~ 110 kg nitrocellulose, converted into
alcohol-free substance)
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I 1 6805~
40 kg Nitroguanidine
2 kg Akardlt II
are introduced into a 400 litre kneader~
- A mixture of the following blasting oils which
has been desensitized with solvents is introduced into
this premixed material:
16 kg 1,2,4-butanetriol trinitrate
Methriol trinitrate
16 kg Diglycol dinitrate
lo 40 kg Alcohol-ether mixture.
- After mixing in the kneader, the mixture is left
to ripen for 10 days at about 25C, thoroughly kneaded
again thereafter and subsequently pressed in the hydraulic
press to single hole strands. After cutting, the powder
lS is dried in a warm air stream, optionally under vacuum.
The finished powder has the following composition
within the limits of tolerance:
Nitrocellulose with 12.8 % nitrogen 55.~0% by weight
1,2,4-butanetrioltrinitrate 8.00% by weight
20 Methriol trinitrate 8.00 ~ by weight
Diglycol dinitrate 8.00 % by weight
Nitroguanidine 20.00 ~ by weight
Akardit II 1.00 % by weight
100.00 ~ by weight
Its heat of explosion amounts to about 3960 J/g.
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