EP0137958A2 - Propulsive charge and method for manufacturing - Google Patents

Abstract

Given are a first conventional propellant charge and a second propellant charge according to the invention, both of the mass N of the same propellant charge powder in the same propellant charge casings. The mass N is determined by the loose bed of the propellant powder in question, which can be taken up by the propellant charge sleeve. The curve Sp _{N is} assigned to the first, loosely shaken propellant charge. It shows that the first propellant charge exceeds a limit G1 in an upper service temperature range - it indicates the average maximum permissible gas pressure for a weapon barrel. The first propellant charge is therefore unsuitable. The second propellant charge is assigned the curve Ep _N , which does not exceed the limit G1 in the upper service temperature range and is therefore suitable. This is achieved according to the invention in that a first portion of the propellant charge, which corresponds to approximately 50 to 80% of the mass N, is at least partially compressed and a second portion remaining as the rest of the mass N is loosely poured onto the first portion.

Description

The invention relates to a propellant charge according to claim 1 and a method for its production.

The construction of propellant charges and processes for their production have long been the efforts of experts. An important role here is an increase in interior ballistic performance in order to achieve a higher muzzle velocity for each projectile. An example of this is DE-OS 32 05 152. It relates to a propellant charge for case ammunition and a method for its production, by means of which the capacity is to be increased compared to the known propellant charges, without at the same time resulting in increased workload and a risk to people from solvent vapors. The propellant charge powder bodies are compressed in the propellant charge sleeve by applying external pressure and without the addition of binding agents and / or solvents to a charge density of between 1.0 and 1.5 g / cm and are elastically or plastically deformed with an almost uniform or gradually different compression , wherein portions with the same or different pressures are compressed in sections uniformly or gradually differently in the propellant charge sleeve.

The measures described there are aimed, in particular, at increasing the mass to be accommodated in a given propellant charge sleeve by compressing the entire propellant, possibly in partial quantities.

Although the known process is intended to reduce the possible harmful effects on the personnel involved in the production by dispensing with binding agents and / or solvents, the types of process indicated prove to be disadvantageous in several respects. After the compaction, precautions must be taken to stabilize a free press rim or the propellant charge surface of the compressed propellant charge powder bodies against crumbling and / or throwing up the press level by a separate cover. If several compression steps are required, the propellant case in question must be brought into a special room for compaction after each filling of the loose propellant powder for safety reasons.

• Bei Waffenrohren werden unterschieden:
  • Der Konstruktionsgasdruck als derjenige theoretische Gasdruck, bei dem eine schädliche bleibende Formänderung des Waffenrohres gerade noch vermieden wird;
    • der Abnahmegasdruck als derjenige, mit dem ein neues Waffenrohr ein- oder mehrmals belastet wird, um seine Sicherheit zu überprüfen.Dieser Gasdruck liegt nahe dem Konstruktionsgasdruck, meistens ein wenig darunter;
    • der maximal zulässige Gasdruck, der außer bei der Abnahme auch unter ungünstigen Bedingungen nicht überschritten werden darf;
    • der mittlere Gasdruck bei 50° C Pulvertemperatur, der unter dem maximale zulässigen Gasdruck liegt und
    • der mittlere maximale Gasdruck bei 21° C Pulvertemperatur (Gebrauchsgasdruck), der unter mitteleuropäischen Verhältnissen als Bezugswert für die Verschleißlebensdauer der Geschützrohre verwendet werden sollte.

In connection with the present invention, an expanded concept of indoor ballistic performance enhancement is introduced. This will be discussed in more detail.

• A distinction is made between gun barrels:
  • The construction gas pressure as the theoretical gas pressure at which a harmful permanent change in shape of the weapon barrel is just avoided;
    • the take-off gas pressure as the one that is used to load a new weapon barrel one or more times to check its safety. This gas pressure is close to the design gas pressure, mostly a little below it;
    • the maximum permissible gas pressure, which may not be exceeded under adverse conditions, except during the acceptance;
    • the mean gas pressure at 50 ° C powder temperature, which is below the maximum permissible gas pressure and
    • the average maximum gas pressure at 21 ° C powder temperature (service gas pressure), which should be used as a reference value for the wear life of the gun barrels under Central European conditions.

For further explanation, reference is made below to two diagrams (FIGS. 1 a and b), from which the influence of the use temperature on the muzzle velocity on the one hand and the average maximum gas pressure, p on the other hand, can be seen for a loosely poured propellant charge. A propellant charge powder is assumed which has no harmful pressure anomaly in the lower operating temperature range, for example in the form of dreaded pressure peaks.

An essential fact evident from the diagrams is the gas pressure increasing with the use temperature, which is accompanied by an increasing muzzle velocity: the p, T curve, with its steep rise against the maximum permissible gas pressure, indicates a sensitive limit given by the latter.

The object of the invention and its solution is directed to a propellant charge with a structure by which in the upper operating temperature range the increase de.s during the development of the shot maximum gas pressure can be influenced with increasing temperature until it is eliminated.

An inventive method for producing the propellant charge in question is characterized by astonishing simplicity. This is explained below and reveals the multiple advantages that result from the invention.

The starting point is a propellant charge powder for which a p, T curve according to the above-mentioned diagram exists in the case of loose bulk and without binding agent and / or solvent, and in a first example from a corresponding total mass N of the propellant charge. Of the total mass N, a first portion of preferably about 50 to 80% is at least partially compressed. This will be discussed in more detail later. In the case of a propellant charge according to the invention, in which a second portion as the remainder of the total mass N is loosely poured onto the first portion, the above-mentioned pressure increase can advantageously be influenced with increasing temperature until it is eliminated. In the present case, the increase in performance consists in the possible Bombardment of a weapon barrel, which is designed for a certain maximum gas pressure, with a propellant charge that would no longer be permissible if the propellant powder was poured loose due to the steep rise in the p, T curve at higher operating temperatures.

If a weapon barrel with a higher maximum permissible gas pressure is now available, then a total mass M> N can be assumed in a second example. Is then moved back to the above-described manner is achieved an ⁱ nnenballistische increased performance at a pressure p <p _maxzul: From the graphs (Fig. 2a and b), namely clear that the influence of the operating temperature during the transition from 21 ° C to 52 ⁰ C is eliminated. In the first example, the increase in performance is given by an improved service life of the weapon barrel and in the second example by a higher muzzle velocity of the projectile. From this, the above-mentioned expansion of the concept of increasing performance within the scope of the present invention becomes clear.

If the method is carried out directly in a propellant charge sleeve, then one with a cross-section that is circular cylindrical essentially over its entire length should first be considered. The effective area of a press ram for compression can correspond to the clear internal cross section of the propellant charge sleeve, and the first portion can be compressed overall.

In the case of a propellant charge case with a comparatively smaller clear inner cross section of a case mouth (bottle case), a press ram adapted to the latter was used. It cannot be avoided here that loose propellant charge bodies move in a circular gap between the circumferential surface of the ram and the inner wall surface of the propellant charge sleeve against the direction of the ram during compression. Strictly speaking, this only results in a partial compression of the first portion. Surprisingly, however, this does not have a disadvantage, and from this fact the simplicity of the method is evident - also with regard to the fact that only a small amount of equipment is required.

If the propellant charge is to be incorporated according to the invention of an at least partially combustible propellant charge sleeve - this can apply to ammunition in the caliber range below 20 mm to over 120 mm - it is advisable to compress the first portion in a comparatively smooth-walled device for which the pressure load when compressing the first share is designed. From this device, the compressed - possibly, as in the case of the bottle sleeve, only partially compressed - the first portion can be transferred to the aforementioned propellant charge sleeve by axial pressing. In order to avoid disadvantageous wall friction, a thin-walled tube can be arranged in the propellant charge sleeve before being transferred and then removed again.

The invention is explained below with reference to the drawing.

• Fig. la bis 2b jeweils zwei einander zugeordnete Druck-Temperatur- und Geschwindigkeits- Temperatur-Diagramme, ferner jeweils in einem längsaxialen Schnitt
• Fig. 3 eine Vorrichtung zum Durchführen des Verfahrens in einer flaschenförmigen Treibladungshülse,
• Fig. 4 eine Vorrichtung zum Durchführen des Verfahrens außerhalb einer Treibladungshülse und
• Fig. 5 eine wenigstens teilverbrennbare Treibladungshülse, die zur Aufnahme eines in der Vorrichtung nach Fig. 4 verdichteten Anteils einer Treibladung nach der Erfindung vorbereitet ist.

Show it:

• Fig. La to 2b each have two associated pressure-temperature and speed-temperature diagrams, further in each case in a longitudinal axial section
• 3 shows a device for carrying out the method in a bottle-shaped propellant charge sleeve,
• Fig. 4 shows a device for performing the method outside a propellant charge and
• 5 shows an at least partially combustible propellant charge sleeve, which is prepared for receiving a portion of a propellant charge compressed in the device according to FIG. 4 according to the invention.

A curve Sp _N in FIG. 1 a illustrates the behavior of a propellant charge from a propellant charge loosely poured into a propellant charge sleeve. The curve in question shows that in the upper service temperature range a horizontal limit Gl, which indicates the mean maximum permissible gas pressure for a first weapon barrel, is exceeded by the curve Sp _n in the steep slope (dashed part). The propellant charge is therefore unsuitable for the relevant temperature range. A curve S _{vN is plotted} in FIG. _1b for the loose propellant charge. A curve E _pN in FIG. _{1 a} shows the behavior of a propellant charge according to the invention, the mass N of which corresponds to that of the loosely poured propellant charge. In the upper service _{temperature range} , the curve E _pN remains flat below the limit Gl: the method according to the invention consequently assumes that the propellant mass N remains the same - in both cases the same propellant is assumed sungshülse - the suitability of the propellant charge for the weapon barrel achieved in the upper operating temperature range. This results in an increase in performance in the expanded sense mentioned at the beginning.

In the diagrams according to _FIGS . 2a and 2b, two curves, S _pN and E _pM as well as S _vn and E _vM , are again drawn. In Fig. 2a is for a second weapon barrel, which is more resilient than the first gun barrel mentioned in connection with Figures la and lb. A horizontal limit G2 is consequently assigned a higher pressure than the limit Gl in Fig. La. The corresponding curves S _pN and S _vN correspond to those from _{FIGS. 1 a} and _{1 b} , ie there is the same propellant charge of mass N in bulk. The two corresponding curves E _pM and E _vM characterize the behavior of a propellant charge according to the invention, the mass M of which is greater than that of the bulk propellant charge known from _{FIGS. 1 a} and _{1 b} (mass N). As in FIGS. 1 a and 1 b, the same propellant charge sleeve and the same propellant charge powder are again assumed. The propellant charge of loose fill can now be used, but from the course of the curves E _pM and E _VM for the propellant charge according to the invention, the interior ballistic performance increase in the conventional sense mentioned above compared to the propellant charge of loose fill is clearly recognizable. A modified but similar course of the curves E _pM and E _vM can be achieved when using different propellant powders.

3 shows a device VI for carrying out the method according to the invention in a bottle-shaped propellant charge sleeve 10 with a sleeve wall 11 and a sleeve base 12. In the sleeve base 12, a threaded bore 14 is provided for a propellant charge lighter. The propellant charge sleeve 10 ends at the top in a sleeve neck 16. The device V1 consists of a thick-walled circular-cylindrical tube 18 with an inner flange 19 on the top side. A bottom piece 20 engages on the underside in the tube 18 and, in addition to a central axial receiving bore 22, has horizontal locking bores 21. The latter correspond to locking bores 18 'in the tube 18. The propellant charge sleeve 10 is received on the bottom side in the base piece 20, with fixing means 23 engaging through the bores 18' and 21 in an extraction groove 24 on the sleeve bottom side. For this purpose, the propellant charge sleeve 10 has first been inserted with the base piece 20 in the direction of an arrow 54 into the tube 18, aligned with the central longitudinal axis A. The sleeve neck 16 is located in the area of a coaxial circular opening 26 in the inner flange 19. A funnel 28 is placed on an unspecified top surface of the inner flange 19 and is surrounded by two spacer rings 30 and 32 in the case shown. A circular cylindrical press die 34 with a press surface 38 on the underside has a fixing groove 36 in the upper free end. With the latter, the press die 34 is received in a holder 40 with radial bores 42. Only indicated fixing means 43 in the bores 42 engage in the groove 36 and fix the press ram 34 in the holder 40.

A first portion of a propellant charge is poured in the form of loose bulk powder through the funnel 28. This first part is about 50 to about 80% of the total mass of the propellant to be incorporated. After the first portion 44 has been filled into the propellant charge sleeve 10, the holder 40 is moved in the direction of an arrow 52 with the press ram 34 fixed therein, with the application of a predetermined pressure. The pressing surface 38 comes into contact with a surface of the bed, not shown, and a part 46 of the first portion 44 is compressed. Since the outer diameter of the press ram 34 is smaller than the clear inner diameter of the propellant charge sleeve 10 in the region of its wall 11, an annular cylindrical cavity 48 remains, in which a small amount 50 of uncompacted propellant charge powder remains. In the case shown is the compression of the part 46 of the first portion 44 completed as soon as a lower annular surface 41 of the holder 40 touches an upper circular surface 32 of the upper spacer ring 32. After pressure relief, the holder 40 is moved with the press ram 34 in the direction of an arrow 54 until the funnel 28 is released. A second portion of the propellant charge remaining as the remainder is then loosely poured onto the first portion 44.

In the case shown, a dummy body 15 is arranged in the threaded bore 14 for the propellant charge lighter and in the receiving bore 22 of the base piece 20. The part of the dummy body 15 protruding into the interior of the propellant charge sleeve 10, which is not described in any more detail, is essentially the same dimension as the propellant charge lighter. Therefore, after removing the dummy body 15, the propellant charge lighter can easily be inserted into a channel 15 'which remains in the compressed part 46 after removing the dummy body 15.

Fig. 4 shows a device V2 with a circular cylindrical tube 60 of sufficient wall thickness in which a bottom piece 62 is inserted on the underside. The latter has a central axial threaded bore 64 for receiving a dummy body 66. A press ram 68, the outside diameter of which corresponds to the inside diameter of the tube 60, has a pressing surface 70 on the underside and a rear actuating rod 72. A central axial bore 72 ′ creates an interior space 73 that extends into a free upper end 75 of the rod 72. Vent holes 74 'connect the interior 73 with the surrounding atmosphere. Radial bores 79 are provided in a holder 76. Bolt-shaped fixing means 68 grip through these and fix the press ram 68 with its rod 72 in the holder 76 via recesses 75 '. A spacer ring 80 has a central opening 80 'which is adapted to the outer diameter of the rod 72. The spacer ring 80 lies with a flat underside surface 81 ′ on an upper-side flat circular ring surface 61 of the tube 60. Before filling one The first part of the propellant charge in the form of loose bulk powder in the interior 61, the ram 68 is removed from the latter. After the spacer ring 80 has been pushed over, it is fixed in the holder 76 and moved in the direction of an arrow 82 along a central longitudinal axis A while applying pressure against the loose powder filling of the first portion of the propellant charge. The dummy body 66 projecting over a top surface 63 of the base piece 62 corresponds essentially to the dimensions of a propellant charge lighter. When the ram 68 moves downward, its free end 67 gets into the bore 72 ', the air being able to escape from the interior 73 through the ventilation bores 74'. The first portion 86 of the propellant charge is compressed as soon as the receptacle 76 with its underside circular ring surface 77 touches the top surface 81 of the spacer ring 80.

If the propellant charge is to be incorporated in a circular cylindrical inner cross section, not shown, of a metallic propellant charge sleeve, it can be provided with the dummy body 66, into which the tube 60, which is adapted to the outside diameter of the propellant charge sleeve, is inserted from below from its inside diameter; in this case, the outer diameter of the ram 68 must be adapted to the clear inner diameter of the metallic propellant charge sleeve, not shown.

• Die Treibladungshülse 90 weist einen Boden 94, beispielsweise aus Metall, mit einer zentral axialen Gewindebohrung 96 für einen Treibladungsanzünder 98 auf. Mit dem Boden 94 ist ein verbrennbarer Teil 100 der Treibladungshülse 90 fest verbunden. Der in der Vorrichtung V2 nach Fig. 4 verfestigte erste Anteil 86 der Treibladung soll nun in einen Innenraum 97 der Treibladungshülse 90 übergeführt werden. Um eine Beschädigung einer Innenwandfläche 101 des verbrennbaren Teils 100 der Treibladungshülse 90 zu vermeiden, wird eine Metallhülse 102, die dem lichten Innendurchmesser des verbrennbaren Teils 100 angepaßt und in der Zeichnung zur Verdeutlichung übermäßig dickwandig dargestellt ist, in den Innenra.um 97 eingeführt. Nach Entfernen des Bodenstücks 62 und des Blindkörpers 66 (siehe Fig. 4) wird die Anordnung nach Fig. 5 achsfluchtend unter der Vorrichtung V2 fixiert. Beim Ausdrücken des verfestigten ersten Anteils 86 der Treibladung gerät der Treibladungsanzünder 98 in einen von dem Blindkörper gebildeten Kanal 88. Sobald der verfestigte erste Anteil 86 der Treibladung in die Treibladungshülse 90 übergeführt ist, wird die glatte Metallhülse 100 an ihrem oberseitigen Rand 104 in Richtung eines Pfeils 108 wieder aus der Treibladungshülse 90 entfernt, und der zweite Anteil der Treibladung wird als loses Schüttpulver aufgebracht.

If the propellant charge of a propellant charge sleeve according to FIG. 5 is to be incorporated, the procedure is advantageously as follows:

• The propellant charge sleeve 90 has a base 94, for example made of metal, with a central axial threaded bore 96 for a propellant charge lighter 98. A combustible part 100 of the propellant charge sleeve 90 is fixedly connected to the bottom 94. The first portion 86 of the propellant charge solidified in the device V2 according to FIG. 4 is now to be transferred into an interior space 97 of the propellant charge sleeve 90. Damage to an inner wall surface 101 of the combustible part To avoid 100 of the propellant charge sleeve 90, a metal sleeve 102, which is adapted to the inside diameter of the combustible part 100 and is shown in the drawing as being excessively thick-walled for clarity, is introduced into the interior space around 97. After removing the base piece 62 and the dummy body 66 (see FIG. 4), the arrangement according to FIG. 5 is fixed under the device V2 in alignment with the axis. When the solidified first portion 86 of the propellant charge is squeezed out, the propellant charge lighter 98 gets into a channel 88 formed by the dummy body. As soon as the solidified first portion 86 of the propellant charge has been transferred into the propellant charge sleeve 90, the smooth metal sleeve 100 on its top edge 104 becomes one Arrow 108 removed from the propellant charge sleeve 90 again, and the second portion of the propellant charge is applied as loose bulk powder.

It goes without saying that, in the case of a propellant charge lighter that is considerably longer than the dummy body 15 according to FIG. 3, the press ram 34 has a central axial bore for the longer dummy body and then, if appropriate, also has a vent hole as in the device V2 in FIG. 4 must be provided. The spacer rings 30, 32 and 80 are interchangeable, so that the penetration depth of the press ram 34 or 68 can be changed to achieve a predetermined compression of the respective first portion 44 or 86 of the propellant charge.

Claims (10)

1. Propellant charge with a structure by which the increase in the maximum gas pressure occurring during the shot development can be influenced with increasing temperature in the upper operating temperature range until it is eliminated. 2. A method for producing a propellant charge according to claim 1, characterized by the following method steps: a) a predeterminable first portion of a total mass of the propellant charge is at least partially compressed as bulk powder without the addition of binding agent and / or solvent (s) and b) a second part remains as the rest of the total mass of the propellant charge as loose bulk powder and forms a part of the propellant charge close to the floor during the finished laboratory work. 3. The method according to claim 2, characterized by the following process steps: a) the first portion is compressed in a device, b) the first portion is transferred into a propellant charge case and c) the second portion is loosely added to the first portion. 4. The method according to claim 2, characterized by its implementation in a propellant charge sleeve. 5. The method according to claim 2, 3 or 4, characterized in that the first portion preferably corresponds to about 50 to 80% and the second portion to the respective rest of the total mass of the propellant charge. 6. The method according to any one of claims 2 to 5, characterized in that the total mass of the propellant charge corresponds to a mass N, which can be taken up as a loose bed of the same propellant charge powder from a same propellant charge sleeve. 7. The method according to any one of claims 2 to 5, characterized in that the total mass of the propellant charge corresponds to a mass M which is greater than a mass N according to the characterizing part of claim 6. 8. The method according to claim 6 or 7, characterized by the use of different propellant powder. 9. The method according to any one of claims 3 to 8, characterized by the following additional method steps: a) a dummy body, which corresponds at least to the dimensions of a propellant lighter protruding into the propellant charge sleeve, is removably arranged at least for filling and compressing the first portion of the propellant charge and b) the dummy body is replaced by the propellant charge lighter. 10. The method according to any one of claims 3 and 5 to 9, in particular when using an at least partially combustible propellant charge sleeve, characterized in that a means for reducing the wall friction is introduced into the propellant charge sleeve for transferring the compressed first portion and again after transferring the first portion Will get removed.

Images