Title of Invention

AN INCENDIARY COMPOSITION AND A PROCESS FOR THE PREPARATION OF THE SAME

Abstract An incendiary composition comprising 93-97% by weight of zirconium metal powder 3-7% by weight of natural rubber and 0-0.5% by weight an anti-oxidant as herein described and 0-0.5% by weight an anti-fungal agent as herein described. Further there is provided a process for the preparation of an incendiary composition comprising the steps of: preparing natural rubber gel by soaking natural rubber sheets along with anti-oxidants as herein described and anti-fungal agents as here described, free from foreign matters, for 48-72 hours, stirring the entire mass at regular intervals until the gel attains a homogeneous and uniform consistency and becomes free from lumps of natural rubber and transferring it to a high shearing mixer like sigma mixer; adding zirconium metal powder 93-97% by weight in installments to the homogeneous and uniform gel obtained from step (i) in the sigma mixer for few minutes, mixing it in forward and reverse directions after every addition of zirconium metal powder, mixing the entire batch after the addition of entire mass of zirconium metal powder, preparing incendiary composition pieces by attaching a solvent recovery unit to the said sigma mixer, allowing an uniform viscous mass of the said incendiary composition dough to be made, transferring the said dough into trays and making it solvent free by evaporating and pudding the mass, cutting the rubbery composition into pieces and drying it to the ambient temperature; compacting the incendiary composition through a hydraulic press platform and coating the compacted incendiary pellets to the required thickness with a resin prior to assembly in the munitions casing.
Full Text FIELD OF INVENTION:
This invention relates to incendiary compositions and more particularly to incendiary compositions made from zirconium metal powder
PRIOR ART:
Incendiary compositions are chemical agents, which, when suitably initiated, evolve large amount of heat. Incendiary devices are used to initiate destructive fires in a variety of combustible targets like fuel and ammunition dumps, clothing, industrial installations, base camps, refineries etc. Incendiary devices can be in the form of gun projectiles, bombs, warheads, or clusters of ammunition. These devices can be delivered to the targets by guns, rockets, missiles or aircraft. The tactical use of such devices is to create a psychological fear of mass destruction by creating fire amongst troops during operations, The efficiency of the incendiary composition depends on the total heat output, duration of burning, spread area, flame temperature, rate of transfer of heat energy to the target etc. Ignition and dispersion of incendiary compositions may be achieved by using centrally placed HE bursting charge to scatter the flammable burning mass.
Incendiary compositions can be broadly classified into following categories: (a) Liquids (b) Gels and (c) Solids.
Liquids incendiary compositions comprise of hydrocarbons like benzene, gasoline, toluene etc. or pyrophoric organic chemicals like triethyl aluminium, diethyl zinc etc. These compositions have short storage life and low temperature out put. These are hazardous in nature, difficult to handle and are not suitable for use with spinning type of projectiles. The notable gel type incendiary compositions are Napalm based incendiaries. The physical nature and performance characteristics of the liquids are improved by converting them into high viscosity gels by the addition of thickening agents. These gel type incendiary compositions, though effective, are suitable only for non-spinning type of projectiles like bombs, rockets or mortars.
Solid incendiary compositions overcome the major defects associated with liquid and gel incendiaries, especially in terms of shelf life, temperature output and suitability for application in spinning projectiles. They can be further classified as thermites, pyrophoric compositions and high explosive incendiary compositions. Thermites, also termed pyrotechnic incendiaries, are essentially mixtures of oxidiser and fuel in desired proportion and need a special ignition system for their reliable ignition. They generate a very high temperature, and dispersion is limited to ejection in only one direction. Pyrophoric metal powders/alloys like zirconium, titanium magnalium are used as incendiaries. They are bound in polymeric material to reduce their sensitivity and can be initiated and dispersed over the desired area by a pyrotechnic chain or a bursting HE charge. The latter method covers a wide area. . The burning fragments generate high heat and burn for sufficiently long duration to set on fire any combustible items they may come in contact with. Other pyrophoric elements are phosphorus, sodium, potassium, etc.
Phosphrous produces more smoke and less heat, while sodium and potassium are difficult to ignite in dry conditions. They require special conditions during storage and use. Another class of incendiaries termed high explosive incendiaries contain metal powders like aluminium, magnesium, zirconium etc. in the matrix of RDX/TNT or TNT or RDX/Wax etc. These compositions produce fire-balls of limited size and rnrlli-second duration.
The present invention relates to a high explosive incendiary composition, which utilises zirconium metal powder. The incendiary compositions, which utilise zirconium metal powder, are known in the art. However, these incendiary compositions, utilising zirconium metal powder, suffer from various disadvantages.
For example, an incendiary composition comprising zirconium or hafnium metallic sponge particles and organic binder Teflon, is already known in the art. However, this incendiary composition suffers from the disadvantage that this is prone to ignition and explosion during compaction of zirconium or hafnium metallic sponge particles due to the adiabatic compression of air in fissures between the surfaces.
Another incendiary composition, comprising zirconium or titanium metal powder and an organic binder free from halogen is known in the art. In this incendiary composition, already known in the art, the binder is mixed with the metal powder in a conventional manner. This incendiary composition also suffers from the following disadvantages.
Primary disadvantage of this incendiary composition, already known in the art, is that the coating of the binder over the metal powder is not uniform, thereby affecting the crucial mechanical properties of this incendiary composition.
Another disadvantage of this incendiary composition, already known in the art, is that it has low burning duration due to the large surface area of the metal powder.
OBJECTS OF THE INVENTION:
The primary object of the invention is to provide an incendiary composition and a process for the preparation thereof, which comprises zirconium metal powder dispersed in the matrix of a binder such as natural rubber.
Another object of the invention is to provide an incendiary composition and a process for the preparation thereof, which utilises a relatively an insensitive material rubber as a binder material thereby improving the safety during the handling of the composition.
Yet another object of the invention is to provide an incendiary composition and a process for the preparation thereof, which has higher flame temperature and higher rate of transfer of heat energy to the target.
Still further object of the invention is to provide an incendiary composition and a process for the preparation thereof, which is capable of spreading over a wide area in a burning state igniting combustible materials that it contacts.
Yet further object of the invention is to provide an incendiary composition and a process for the preparation thereof, which are suitable for spinning as well as non-spinning munitions.
Still further object of the invention is to provide an incendiary composition and a process for the preparation thereof, which utilizes the binder material as a fuel.
Yet further object of the invention is to provide an incendiary composition and a process for the preparation thereof, which has a shelf life of more than 10 years in assembled and packed condition under tropical conditions.
Still further object of the invention is to provide an incendiary composition and a process for the preparation thereof, wherein the zirconium powder is dispersed in the binder material thereby reducing the pyrophorocity of the zirconium metal powder and as such making the handling of the incendiary composition safer.
Yet further object of the invention is to provide an incendiary composition and a process for the preparation thereof, which can be compacted or pressed in suitably die punch assemblies to obtain pellets of required configuration.
Still further object of the invention is to provide an incendiary composition and a process for the preparation thereof, which also comprises anti-oxidant and anti-fungal ingredients.
STATEMENT OF INVENTION
According to this invention there is provided an incendiary composition comprising 93-97% by weight of zirconium metal powder 3-7% by weight of natural rubber and 0-0.5% by weight an anti-oxidant as herein described and 0-0.5% by weight an anti-fungal agent as herein described.
Further according to this invention there is provided a process for the preparation of an incendiary composition comprising the steps of:

preparing natural rubber gel by soaking natural rubber sheets along with anti-oxidants as herein described and anti-fungal agents as here described, free from foreign matters, for 48-72 hours, stirring the entire mass at regular intervals until the gel attains a homogeneous and uniform consistency and becomes free from lumps of natural rubber and transferring it to a high shearing mixer like sigma mixer;
adding zirconium metal powder 93-97% by weight in installments to the homogeneous and uniform gel obtained from step (i) in the sigma mixer for few minutes, mixing it in forward and reverse directions after every addition of zirconium metal powder, mixing the entire batch after the addition of entire mass of zirconium metal powder.
preparing incendiary composition pieces by attaching a solvent recovery unit to the said sigma mixer, allowing an uniform viscous mass of the said incendiary composition dough to be made, transferring the said dough into trays and making it solvent free by evaporating and pudding the mass, cutting the rubbery composition into pieces and drying it to the ambient temperature;
compacting the incendiary composition through a hydraulic press Pellets are coated to the required thickness with a resin prior to assembly in the munitions casing.
The composition thus formed gives synergism
The invention will now be illustrated with a working example, which is a typical example to illustrate the working of the invention and is not intended to be taken restrictively to imply any limitation on the scope of the present invention.
Working Example 1
In order to make 1000 gm of incendiary composition, 50 gm of natural rubber, 0.5 gm of antioxidant and 0.5 gm of antifungal agents are soaked into the solvents like benzene, toluene and xylene, spirite etc. for 48-72 hours. The entire mass is stirred at regular intervals. When the gel becomes homogenous and uniform, it is transferred to the sigma mixer. To this mix, 950 gm of zirconium powder, of the average size of 5-500jim, is added and then the entire mass is mixed. The uniform viscous mass of the incendiary mix is transferred into trays and it is made solvent free by evaporating and pudding the mass. The rubbery composition is then cut and made into pieces of uniform sizes and is dried at ambient temperatures. The compacted/pressed incendiary composition or extracted with the help of hydraulic press machines.
It is to be understood that the process of the present invention is susceptible to adaptations, changes and modifications by those skilled in the art. Such adaptations, changes and modifications are intended to be within the scope of the present invention, which is further set forth with the following claims.


WE CLAIM:
1. An incendiary composition comprising 93-97% by weight of zirconium metal powder 3-7% by weight of natural rubber and 0-0.5% by weight an anti-oxidant as herein described and 0-0.5% by weight an anti-fungal agent as herein described.
2. A composition as claimed in claim 1 wherein said zirconium metal powder has an average size of 5-500|um.
3. A process for the preparation of an incendiary composition comprising the steps of:
(i) preparing natural rubber gel by soaking natural rubber sheets along with anti-oxidants as herein described and anti-fungal agents as here described, free from foreign matters for 48-72 hours, stirring the entire mass at regular intervals until the gel attains a homogeneous and uniform consistency and becomes free from lumps of natural rubber and transferring it to a high shearing mixer like sigma mixer;
(ii) adding zirconium metal powder 93-97% by weight in installments to the homogeneous and uniform gel obtained from step (i) in the sigma mixer, mixing it in forward and reverse directions after every addition of zirconium metal powder, mixing the entire batch after the addition of entire mass of zirconium metal powder;

(iii) preparing incendiary composition pieces by attaching a solvent recovery unit to the said sigma mixer, allowing an uniform viscous mass of the said incendiary composition dough to be made, transferring the said dough into trays and making it solvent free by evaporating and pudding the mass, cutting the rubbery composition into pieces and drying it to the ambient temperature;
(iv) compacting the incendiary composition through a hydraulic press platform and coating the compacted incendiary pellets to the required thickness with a resin prior to assembly in the munitions casing.
4. A process as claimed in claim 3 wherein the concentration of natural rubber sheets to the solvent is 57-60 gm to 1 liter.
5. A process as claimed in claim 3 wherein the metal zirconium metal powder has an average sieve size of 5 to 500 ┬Ám.
6. A process as claimed in claim 3, wherein the solvent is for example benezene, toluene, xylene or white spirit.
7. An incendiary composition and a process for the preparation of the same substantially as described and exemplified herein.

Documents:

1113-DEL-2002-Abstract-(09-01-2009).pdf

1113-del-2002-abstract.pdf

1113-DEL-2002-Claims-(09-01-2009).pdf

1113-del-2002-claims.pdf

1113-DEL-2002-Correspondence-Others-(09-01-2009).pdf

1113-del-2002-correspondence-others.pdf

1113-del-2002-correspondence-po.pdf

1113-DEL-2002-Description (Complete)-(09-01-2009).pdf

1113-del-2002-description (complete).pdf

1113-del-2002-form-1.pdf

1113-del-2002-form-18.pdf

1113-del-2002-form-2.pdf

1113-DEL-2002-Form-3-(09-01-2009).pdf

1113-del-2002-form-3.pdf

1113-DEL-2002-GPA-(09-01-2009).pdf


Patent Number 234336
Indian Patent Application Number 1113/DEL/2002
PG Journal Number 25/2009
Publication Date 19-Jun-2009
Grant Date 25-May-2009
Date of Filing 06-Nov-2002
Name of Patentee THE DIRECTOR GENERAL
Applicant Address DEFENCE RESEARCH & DEVELOPMENT ORGANISATION MINISTRY OF DEFENCE, GOVT. OF INDIA, B-341, SENA BHAWAN, DHQ P.O. NEW DELHI-110011.
Inventors:
# Inventor's Name Inventor's Address
1 JAMAN SINGH GHARIA HIGH ENERGY MATERIALS RESEARCH LABORATORY, ARMAMENT POST, SUTARWADI, PUNE 411 021.
2 CHANDRASEKHAR GANAPATI MUDKANNA HIGH ENERGY MATERIALS RESEARCH LABORATORY, ARMAMENT POST, SUTARWADI, PUNE 411 021.
3 JAYANT MORESHWAR SANE HIGH ENERGY MATERIALS RESEARCH LABORATORY, ARMAMENT POST, SUTARWADI, PUNE 411 021.
4 SANJAY VASANT SHIRWALKAR HIGH ENERGY MATERIALS RESEARCH LABORATORY, ARMAMENT POST, SUTARWADI, PUNE 411 021.
PCT International Classification Number C10L 005/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA