DE1796009A1 - Propellant powder with improved performance and stability - Google Patents

Description

Propellant powder with improved performance and stability

The invention relates to monobasic or polybasic propellant charge powders, which are characterized by improved performance and stability compared to known propellant powders, with little or no increase in gas pressures, higher initial velocities and also favorable combustion properties can be achieved have, i.e. have improved properties in both chemical and ballistic terms.

In the case of propellant charge powders, a distinction is made, as is well known, between single-base powders based purely on nitrocellulose and two-base powders Powder, which in addition to nitrocellulose, has another active component as an energy source, for example nitration products polyhydric alcohols, such as nitroglycerin or diglycol dinitrate, while the three-base powder still contains a third Component, also usually contain a nitro compound. In the case of these propellant charge powders, a Controlled combustion takes place with the release of gases that propel the projectile through the barrel of the weapon and out of it and give the projectile a certain initial velocity at the muzzle of the barrel.

The propellant charge powders are marketed both in the form of strip powder and in the form of ball powder. the

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BATH ORIGINAL

Strip powders are plasticized using either water or solvents, deformed by extrusion and then freed from the solvent or water. The ball powders, on the other hand, are made using A lot of water is produced, compared to that with solvents produced strip powders has the advantage of greater security; these powders generally have have a very high bulk density and are therefore very suitable for weapons with high performance with only a small powder loading space.

An essential process in the removal of solvents and water from the propellant charge powders is simultaneous Hardening of the powder surface. It is also o.uch known to add stabilizers, such as diphenylamine, to the propellant charge powders during plasticization, in order to bind the nitrogen oxides and nitrous acid formed during the decomposition of the breakdown products of nitrocellulose and to eliminate catalytic decomposition of the powder. In addition, most propellant powders are used because of their sensitivity subjected to an aftertreatment against friction and also surface-treated, for example in the presence of Alkylarylurea derivatives, urethanes, phthalates, which usually compress and smooth the surface of the powder.

When dealing with propellant powders and improving them the properties of this propellant powder has now surprisingly found that it is possible to or to harden polybasic propellant powder and to improve the ballistic properties insofar as the performance is increased, the stability is increased and at the same time the burning rate can be favorably influenced. The method of manufacture of propellant powder with improved performance and stability is characterized in that one or polybasic propellant powder during or after their manufacture treated with aldehydes. Both aldehydes can be used as aldehydes

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ßAD ORIGINAL

Both phatic and aromatic aldehydes can be used, but generally aliphatic aldehydes and especially formaldehyde are preferred. The aldehyde can be added to the powder tube compound, for example by mixing it with the aqueous solution of an aldehyde in a mixing device, such as a kneading mixer, before shaping. However , the propellant powder can also be brought into contact with aldehydes in vapor form before, during or after the drying process by using them either in gaseous form or as a vaporized solution.

The propellant charge powders treated according to the invention with aldehydes show up against those not treated with aldehydes Powders significantly improve their mechanical, chemical and ballistic properties. You are harder have greater stability and produce higher initial velocities if the gas pressures are not or only slightly increased. the Their performance can either be increased in the firearm itself or in relation to the reduction in the weight of the charge be exploited.

The invention is explained in more detail by the following examples:

example 1

A strip powder consisting of

58.5 Γ 'Nitrocellulose 40.0 Yes Nitroglycerin 0.5 <?:> Diaethyldiphenylurea 1.0 fo Diphenylamine

0.3 pounds of petroleum jelly

is left as a calendered film web in a drying room in which there is an approximately 50 cm high vessel filled with J> 8 vol- # formaldehyde solution, for IJ hours at 50 ^° C. The powder is then further treated in the usual way.

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BATH ORIGINAL

However, the finished powder can also be treated with formaldehyde in the same way, but at a maximum temperature by JO C to remove the nubs of the already napped powder not to affect. Knobs of propellant powder mean the embossing of depressions in the powder film, the powder thickness at the elevations and depressions can be somewhat thinner than the film. This can the surface is enlarged and the distance between the foils be expanded.

In the treatment described above, a strip powder is obtained which is shown in Table 1 below Features:

Table 1 .

Formaldehyde loading weight V Pmax treatment _gm

without 333 309.5 598

with 325 311.6 597

The table shows that the speed (V) of the powder increases in the formaldehyde treatment, but the pressure does not is increased. It was also found that the leveling of the powder is better and the strips are more hard have, the stability of the powder is not impaired and no negative effects on recoil and muzzle pressure can be determined.

Example 2

Similar results are also found with ball powder containing nitroglycerine. Here came two powders (A and B) the following composition for use:

209815/046? «Dom *« ..

approx. A. ß Nitroglycerin approx. ~ < £ 10 Diphenylamine approx. 1 <J 1 / ■■ Dibutyl phthalate approx. 5 ^c /> 6.5: Ether extract approx. 15 pounds 18 < Ex heat cal / g 900 830

These ball powders had the properties given in Table 2 below:

T 3 a b e 1 1 e 2 V
O
m / sec. Pmax
atü powder Formaldehyde-
treatment Loading weight
S. 818
8l4
989
1008 2472
2637
2994
3124 A.
A.
B.
B. without
with
without
with 2.86
2.86
30.0
30.0 example

Also a single base nitrocellulose powder that is as follows was composed

98.4; ■ · nitrocellulose

1.0 % diphenylamine

4.9 % dibutyl phthalate

0.6 % sodium oxalate,

showed a clear increase in performance according to the following table 3:

T a b e 1 1 e 3 Pmax
atü Formaldehyde-
treatment Loading weight
G ^V o
m / sec. 3455
3869 without
with ^ 9.9
^ 9.9 1034
IO63 209815/0462 BATH ORIGINAL.

With the propellant charge powders treated according to the invention, series of shots were also carried out in which, in addition to the charge weight, the speed V_ and the P _{m! JV}

also muzzle pressure, standing cone (atü) and the recoil energy were determined. The results of this series are given in Table 5 below, with powders being examined which had the analytical values given in Table 4:

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SAD ORiGlNAL

a b e 1 1 e

Powder and form
aldehyde treatment I a
without I b
with II a
without II b
with
in the clay
approach II c
with
steam III a
without III b
with
in the kneading
approach III. c
with
steam Nitroglycerin ?> 39.6 39.4 40.73 40.73 39.5 40.9 40.9 38.6 isjdiethyl-diphenyl-
ohurea % 0.65 0.6 0.6 0.6 0.6 0.6 0.6 0.6 (O,
eoAcetone ^c ; j 0.06 0.03 ^ Diphenylamine % 1.04 1.1 1.0 1.0 1.0 1.0 1.0 1.0 ^ Ether extract % 41.7 41.6 42.6 42.6 41.4 42.6 42.6 40.6 O
* »■ Ex heat cal / g 1234 1234/46 1245/46 1241/44 1233/58 1235/39 1233/34 1237/38 JJ deflagration ⁰ C 160-64 164/65 164 165 165 167 166 166

Tabel

powder Loading weight _v Pmax Compression cone Muzzle pressure Recoil energy 00 S. m / sec. atü atü m / kp I. I a 333 308.4 624 530 .0.15 333 310.0 607 506 0.42 333 307.3 591 503 0.27 L. ro
O 333
333 310.1
309.6 605
591 500
489 0.43
0.43 C;
* \ «P
«£ b 325 311.9 609 506 0.36 W.
O cn 325 314.0 614 512 . 0.47 O 325 310.1 596 509 0.15 - ^ 325 314.7 503 0.52 96009 φ 325 315.3 631 518 0.48 II a 330 315.5 634 77 0.25 II b 330 315.8 648 76 0.11 • II c 330 320.0 664 ' 77 0.10 III a 330 316.3 630 76 0.13 III b 330 317.9 668 73 0.10 III c 330 328.2 701 80 0.10

From the test results it is therefore clear that the 'Propellant powder according to the invention considerably improved Have properties compared to the previously known propellant charge powders; despite the reduction in the weight of the cargo For example, the initial speed V is still higher for powder I b at practically the same pressures than with the untreated powder I a.

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BATH ORIGINAL

Claims (4)

Claims 1.), process for the production of propellant charge powders with ^ --- 'Desserter performance and stability, characterized that one treats monobasic or polybasic propellant charge powder with Aledhyden during or after their shaping. 2.) Process according to claim 1, characterized in that the powder raw material is formed with the aqueous solution before it is shaped treated of an aldehyde. 5 ·) Method according to claim 1, characterized in that one Bringing the preformed propellant powder into contact with an aldehyde in vapor form before, during or after drying. 4.) Method according to claim 1 to 3, characterized in that the aldehydes used are those of the aliphatic series, in particular formaldehyde. 209815/0 * 62