US1923327A - Explosive - Google Patents

Description

' which heretofore made Patented Aug, 22, .1933

w "Glenn'At Pritchettand Herbert G. Walker, Reno; a i

; ;Nev., .assignors to Monite Explosives, Inc 1 Reno Nevi;a Corporation of N evada e Drawing; Application August-14, 1931 Our invention relates to free-flowing explosives and has for its objects a process for. producing a free flowing high powered explosive powder;

ing strength and at thesame time relatively dangerous since itmay easily be set ,off by friction or heat. Other powders have beenmade combining the more powerful ,expl'osivesin their combination, but in so" far as can belear-ned such freei flowing powders have not..beer1, rn2 tde -frorn ingredients'iincludi'ng a chlorate base, .probably owing to the, sensitive nature of sodium chlorate such powders.

However, since the inclusion 'of;chlorate makes.

it possible to produce a' powder, ofa strength running up to 760% "or more equivalents .to nitroglycerine dynamite, we worked to. overcome the generally'hazardous nature of powders incorporating this material whileretaining the. valueio f this superior explosive agent,fjand haveproduced 'a powder or better free flowing, qualities. than any powder on thefmarket exceptjblackfpo'wden-"yet V with safety features greatly exceeding any 'commercial explosive powders,obtainable.'

Our invention comprises the useloficertainjingredients, heat-'treated'to reducetheirwaterlcontent, specially sized particles; carrying within their interstices a percentage 'of fdinitrotoluoLQand 1 finally glazed with an organic glazing-1 material, 1 the varying strengths of the'powder being secured by changing the percentage of' sodium chlorate used. The final result being'af'ree flowing powder of high explosive value which cannot besetfoff by direct contact with burning matchesyignited gasoline soaked rags, or such friction and/or percussion as would at time set off most any powder-known, yet withal a-powder which mayv be even more readily exploded by means of a fulminate cap or electrical exploder than low strength bulb powders obtainable.

it impossible to control .est possible absorption: of the oil.+; 1

The'preferred' combination'of ingredients comprising our. -;improved. .i explosive 1arezt sodium. chlorate, sodium nitrate,.wood flour :(cottonwood) Ilpowder, though insome casesnitronaphthalene 1 dinitrotoluol, carbonate of. lime, and lycopodium and nitro-ben zol maybe incorporated; and insteadof' cottonwood flour, bagasse flour has, been 'found'useful; :1

I I Prepariztionlof materials 1'. Thecrystalline or salt ingredients are dried out to ta moisture content pref erably not exceedihgfoiir-tenths ofzone per cent.i(0.4.%). 1

2. The woodiflour'isi dried to a moisture con.-

tent; preferably not exceeding one per cent. I j

.z- 3.1The dinitrotoluene is heated to .a temperature preferably not below 120? F.-'at time of intro- 'du'ctionto the mixture',-:and it should be of a melting -p.ointllyingf between and 10. '3 4. The crystalline or sale ingredients are heated to atem'perature preferably not rbelow 105:F. at

time of mixingetTo secure :the'. fulladvantages of our 'inventio'n it is also necessary-that the salts -used :be& of certain sizes, as. follows I The. sodium: nitrate is crushed: through rolls so adjusted as-to produce'th'e maximum percentage of grains'lying'betwe'en 8 andl8 mesh, and .this is preferably then classified by screening and selectionis made of such particles as will passjan 8 mesh screen and will not pass an 18 mesh screen. "-'.The sodium chlorategis similarly classified to retain particles lyingbetween .50 and 100 mesh. .L'Ihemelted liquid dinitrotoluene is introduced to' :armixture of the other ingredients mentioned z.(omitting the :lycopodium powder) in percent- 'ageszof from about.5% to- 15% in any suitable mixinglapparatus in *a manner .to give the most intimate contact of iparticles to induce the-greatr s Afterlrthoroughly incorporating the dinitr'otoluene, the mass is re-screened through a ten mesh screen to. break up any agglutinated parti-L cles,,and the grains-are". thereafter glazed by ,tumblingin a barrel withabout 2%.of licopodium 'Dowder-.:, 9.

vfIormul a; 7 1 I it is possible t6 ent irely bnii t (the. chlorate salt and obtain a 5% strength powder" by u'singfthe livllow e e s 7 Sodium nitrate"; t about 85 Dinitrotoluol 10 Wood flour. 5 Qarbonate of lime 1 I Percent v While a 40% strength powder would contain:

Other strengthsof powder below,40% or 'uplto 60% or more are producedby changing the relative amount of chlorate to nitrate, increasing-tli chlorate and reducing the nitrate in substantially equal amounts, the 60% powder would v contain 60% chlorate and 2 5 nitrate. ff 5. I v 1 The product 7 z z-. The resulting powder is thoroughly non i plastic so that it is free flowing to an unusual degree so as to pass readily into small'bore holes.

bIt is very resistant to moisture. c--Ithas an average specific gravity of about 41.642 relative to silicasand .of 20/30 screen finer of temperature.

ness taken-at 1.00 and is .therefore from 6% 'to j '9%-:denser than most standardbrands of ifree fiowinglpowde'r available on the market so that a given weight will occupy less space, or conversely, .a given'bulk has greaterexplosive energy:

. d-It is free from any tendency toseparate its liquid from other ingredients.

e-Is perfectly stable under extreme variations VIP-Cannot, beset off 'by direct contact with burning. matches or-cigarettes; A test of burn ing'a whole .box of Domino matches on' top .of a pile of .500: 'grams'of powder, or pouring the powder'on the burning: matches failed .to ignite it. It could not .beignited from a burning fuse.

A gasoline soaked rag .:placed on a-pile of 'the' powder and ignited lonly fused'the' top; layer to a crust, and uponremovalof the crust theplower layer was found to shoot as well'as' before, gr-Standard frictionitests 'made' on "0.8. Gov- .ernment Bureau of Explosives'type friction pendulum withiibre shoeon steel anvil; gave no failu'res in ten trials. Tenifurthe'r. trialsrwith steel shoe were'made with no-failures though-this test was one no high explosive of this type would pass.

An extra severe test was made, 8 or 10, wherein .7% of sandwas mixed'with the charge; ofexplosive,thus inducing the greatest possiblefriction' andlwith steelupoh steel, but no failures .resulted.from the test. I 1

. a 'In developing our invention we havediscovered that itis-necess'ary, in order toproduce a stable andreliable product that the dinitrotoluoliused shouldhave a melting point lying-substantially I between and centigrade, and that the frac- 'tions above and below-thisrange'should be elim; inated, and that lack. ofthis knowledge was one of .the-causeszof failure in earlier: attempts to produce a powderof this nature. 1 w H We have also'found, that while instead of the sodium salts, the corresponding potassium and ammonium salts, may in'some instances be used,

the resulting explosive is lacking in several of the advantages foundinoiir product.

. Fromtheabove descriptionof our invention it will be seen that'we have produced ahigh powered explosive of great stability and havingremarkable safety attributes,an'dfrom 'a'bas'e heretofore generally considered unreliable. We therefore feel entitled to claims commensurate with the importance of our contribution to the art and accordingly we claim; 7 Y

1 An explosive powder in granular form containing. dinitrotoluol and sodium chlorate and with the individual grains of the powder glazed exteriorly with lycopodium powder.-

j The process of making an explosive powder of sodium nitrate, dinitrotoluol and cellulose flour, which comprises reducing the water content ofthe nitrate to less than one-half of one per flour, which comprises reducing the water content of the nitrate to less than one-half of one per centreducing the water content of the cellulose 'flourto below 1 4%, and heating the dinitrotoluol to a temperature above 115 degrees F. before mixing the same.

j Q LLIhBLP I'OCGSS specified in claim 2 plus wherein "the' nitrate has been classified into grains lying substantially between 8 and'18 mesh.

' 5. The process of making an explosive powder which comprises substantially drying sodium nitrateand sodium chlorate, granulating and classifyingthe salts to'brin'g the nitrate substantially between 8and 18 mesh, and the-chlorate between -50 and 100 mesh, incorporating therewith a quantity of organic flour and-dinitrotoluol, and granulating the mass. I I s s 6. The process of making an explosive'powder which comprises substantially drying sodium nitrate and sodium chlorate, granulating and classifying the salts'to bring the nitrate substantially between 8 and 18 mesh, and the chlorate between 50'and 100 mesh, incorporating therewith a quantity of organic [flour and dinitrotoluol and an alkali; V

'7. The process of making an explosive powder tity of organic flour and dinitrotoluol, granulating hemass and glazing the grains exteriorly. 8. The process of making an explosive powder which comprises substantially ,drying sodium nitrate an d sodium chlorate, granulating and classisodium chlorate with particles substantially all graded in size between 50 to 100 mesh, and'dinitrotoluol of a grade hard at ordinary temperatures.

. --GLENN A. PRITCHETT." 1 HERBERT G. WALKER.

. powder comprising which comprises substantially drying sodium nitrate and sodium chlorate, granulating and classifyingfthe salts to bring the nitrate substantially betweenfS and 18 mesh, and the chloratebetween -50 and 100 mesh;incorporating therewith a quan-= flgrfladedin size between 50 to 100 mesh, sodium ni-