Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for producing a propellant

a technology of propellant powder and powder, which is applied in the direction of explosive working apparatus, cartridge ammunition, weapons components, etc., can solve the problems of high cost, undesirable side effects, and high temperature-dependent performance of propellant powders

Inactive Publication Date: 2006-11-30
NITROCHEM WIMMIS +1
View PDF8 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Performance increases that must be realized with new developments are extremely cost-intensive.
The problem with providing these desired new high-performance propellant powders is that undesirable side effects must be avoided.
The temperature-dependent performance of such propellant powders has considerable disadvantages, for example a low first hit probability and considerably lower projectile energy during the deployment at normal and, above all, at low temperatures.
The limiting factor is always the peak gas pressure occurring at high temperatures.
As a result, the propellant powder ignition is delayed considerably.
However, the mechanism for this appears to be unclear so far.
Processes of this type, however, are hard to control and contain an immense safety risk.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for producing a propellant
  • Method for producing a propellant
  • Method for producing a propellant

Examples

Experimental program
Comparison scheme
Effect test

example 1 (

FM 2032n / 9)

[0150] An amount of 90 kilograms of untreated grain, produced with a matrix of 10.5×(19×0.2) mm, is placed inside the treatment apparatus (treatment drum) at a temperature of 16° C. Added to this are 180 grams graphite (0.2 weight % relative to the propellant powder) and a solution of 1440 milliliters of 80% by volume ethanol (16 ml per kilogram propellant powder) and 225 grams of polytetrahydrofuran 650 (0.25 weight % relative to the propellant powder).

[0151] In the gastight, sealed drum, the mixture is mixed at 16° C. while rotating at 14 rpm for 30 minutes. Following this, the lid is removed from the polishing drum and the solvent is allowed to evaporate during a period of 105 minutes.

[0152] The treated propellant powder is dried at 60° C. over a period of 3 days.

[0153]FIGS. 1a-c contrast the test results for burning a propellant powder in the ballistic bomb. The ratio of the momentary pressure P to the maximum pressure Pmax is plotted on the abscissa while the dyna...

example 2 (

FM 2712n)

[0156] Placed into a large treatment apparatus are 220 kilograms of untreated grain, produced with the aid of a 12.0×(19×0.20) mm matrix, and preheated to 30° C. Added to this are 187 grams (0.085 weight % relative to the propellant powder) of graphite and subsequently a solution of 264 grams polytetrahydrofuran 650 (0.12 weight % relative to propellant powder) and 2040 grams 75% by volume ethanol (10.6 milliliter per kilogram propellant powder). The mixture is mixed in the closed drum for 60 minutes at 30° C. and with a rotational speed of 8.25 rpm. Following this, the lid of the polishing drum is removed, another 187 grams (0.085 weight %) of graphite are added and the solvent is allowed to evaporate from the rotating drum during a period of 30 minutes.

[0157] The propellant powder treated in this way is dried over a period of 3 days at 60° C.

example 3 (

FM 2758n)

[0158] This treatment is realized in exactly the same way as for Example 2.

[0159] To confirm the mechanism of the temperature-independent burning of the propellant powder, powder grains were tested in a quenching bomb at different temperatures. A rupture disc opened the bomb at approximately 700 bar and the burned propellant grains are thrown into a water bath and quenched. The recuperated, partially burned propellant grains were then photographed.

[0160]FIGS. 2a-c show the burned propellant grains, which were fired at −40° C., +21° C. and +50° C. It is clearly noticeable that at low temperatures, other form function characteristics contribute to the burning mechanisms than at high temperatures.

[0161]FIG. 3a, on the other hand, shows the pressure bomb test results for the untreated grain FM2708n. FIGS. 3b and 3c show the test results for the two samples FM 2712n and FM2758n. It is quite obvious that the temperature dependence of the propellant powder burning could be redu...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
temperatureaaaaaaaaaa
temperatureaaaaaaaaaa
temperatureaaaaaaaaaa
Login to View More

Abstract

The proposed propellant powder exhibits a temperature-independent burning behavior and high ballistic stability. The production process starts with a perforated bulk powder grain, which is processed inside a mixing apparatus with a solid material, a plug-stabilizing moderator or deterrent (if necessary also a radical initiator) and a low-viscous liquid. With a minimum amount of solid material, moderator or deterrent and liquid and because of the continuous mixing, the form function is influenced in such a way that the gas-formation rate is practically independent of the propellant powder temperature. As a result, the muzzle energy at the normal temperature and, above all, at a low deployment temperature can be increased markedly as compared to that of a standard propellant powder. With the propellant powder according to the invention, for which the grain has at least one perforation that discharges with an opening to the outside surface of the grain, wherein the opening is closed off with a plug, the plug has a temperature-dependent mobility. As a result, the plug has a higher mobility for a lower deployment temperature than for a higher deployment temperature, so that the plug permits a faster hole burning at a lower deployment temperature than at a higher deployment temperature.

Description

TECHNICAL FIELD [0001] The invention relates to a propellant powder, for which the grain has at least one perforation that discharges with an opening to the outside surface of the grain, wherein this opening is closed off with a plug. The invention furthermore relates to a method for producing a propellant powder of this type. PRIOR ART [0002] Propellant powders (TLP) for conventional barrel weapon systems should be configured such that they can function safely and without problems under different environmental conditions (system-specific factors). Great temperature differences during the weapon deployment represent one of the most important influences, which a propellant or ammunition manufacturer must take into consideration. Thus, local and / or global climactic conditions may require secure propulsion solutions for a temperature range of between −54° C. and +63° C. / +71° C. (and up to +100° C. for the deployment from an aircraft). [0003] Since propellant powders naturally burn temp...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(United States)
IPC IPC(8): C06B45/00C06B21/00C06B45/22F42B5/16
CPCC06B21/0083F42B5/16C06B45/22
Inventor FAHRNI, MARKUSVOGELSANGER, BEATSTEINMANN, ALFREDOSSOLA, BRUNOJECK-PROSCH, ULRIKEHUBER, ALEXANDERRYF, KURT
Owner NITROCHEM WIMMIS