Patented Oct. 21, 1930 1,778,718

UNITED STATES PATENT OFFICE ROY LINDEN BILL, OF WILMINGTON, DELAWARE, ASSIGNOR TO ATLAs POWDER COM PANY, OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE GELIGNITE AND GELATIN NoDrawing. Application filed December 14, 1928. Serial No. 326,154. The objects of my invention are to provide understood that the use of this material con gelignites and gelatin of such com stitutes a phase of my invention. position that they will possess improved soft It is not necessary to use either pelleted ness and plasticity, better keeping qualities sodium nitrate or pelleted potassium nitrate, 5 in storage, higher propagation sensitiveness, as the entire content of these saltsin my gelig 55 and greater assurance of high rates of de nites or gelatin dynamites. My compositions tonation than have heretofore been readily may include a proportion of either one of possible with known products of this nature. these salts prepared in any well known way My invention further contemplates the as by grinding, but, when using either of the Io provision of gelignites and gelatin dynamites pelleted salts, at least five percent of the total 60 that are more easily and economically content of such salts will be in the pelleted handled in manufacturing operations than condition, because lesser amounts do not pro has heretofore been possible. , vide sufficiently advantageous conditions. An additional feature of novelty and ad There should be nomisinterpretation of the 15 vantage resides in the fact that by the present meaning of gelignites and gelatin dynamites 65 invention I can more readily prepare satis by those skilled in the art. They are explo factory of the types mentioned, sives whose consistency has been effected by with a lower content than the use of more or less nitrated cellulose which heretofore. has an appreciable degree of solubility in 20 Broadly stated, the invention resides in the nitroglycerin. 70 introduction of what I have chosen to call Three examples will be given as follows, “pelleted sodium nitrate' or “pelleted potas but it should be understood that I do not con sium nitrate' into the explosives concerned. fine myself to these examples and that my To avoid any misinterpretation I may define invention covers the entire field of gelignites 25 my meaning as follows, using sodium nitrate and gelatin dynamites in which potassium 75 as the example: nitrate or sodium nitrate are used. Eacample No. 1 w I am concerned with sodium nitrate which Per cent exists in the form of spherical or semi-spheri Nitroglycerin------42 cal particles such as would be formed by sub Nitrocotton------1 30 mitting the molten material to shot towers or Pelleted sodium nitrate------45 80 ejecting it through a spray gun by means of Wood meal------5 air or gas pressure. It is so special and Flour ------6 peculiar in form that even a casual observa Chalk------1. tion would indicate that it could not be Eacample No. 9 85 35 formed by any grinding treatment of coarse Per cent sodium nitrate, or by any of the established Nitroglycerin------5. methods of preparing this salt for use in ex Nitrocotton------2 plosives. Fortunately, for some of the Pelleted sodium nitrate------25 objects of my invention many or all of the Ground sodium nitrate------12 40 pellets are hollow to a greater or less extent. Woodpulp------9 90 place no limit of size on the spherical or Chalk------1. semi-spherical particles. They may be so Eacample No. 3 small that all will pass a 100 mesh screen or Pe cent 2S E. as conditions of application render Nitroglycerin------18 desirable. Nitrocotton ------0.4 ) I have also found that potassium nitrate, Pelleted potassium nitrate------50 pelleted into similar spherical or semi Ground potassium nitrate------5 spherical particles, exerts an advantage, simi Flour------lar to that of pelleted sodium nitrate, in gelig Sulphur ------4.6 59 nites and gelatin dynamites, and it is to be Zinc oxide------1 OC 2 5,778,718 ... ) The advantages of the invention will be for which there is a broad demand among better appreciated after a consideration of consumers. . the following facts: It is known that practi My experience, derived from extended ex cally any may be “dead pressed', perimentation, has demonstrated that explo that is, pressed to a point where it will either sives prepared as described herein possess c detonate with a low order of detonation or better keeping qualities, higher propagation merely burn. Obviously increased pressure sensitiveness, higher rates of detonation and means less or no air spaces between the par greater softness and plasticity than explo ticles. With this condition it is assumed that sives made with ordinary ground sodium ni the failure of explosives to function properly trate, and that such explosives may be more when over-pressed is probably connected. easily and economically manufactured, and s Agelignite or gelatin dynamite may be looked may be made with a lower nitroglycerine con upon as a honey comb of minute air particles tent in the production of a good gelatinized surrounded by films of colloided nitro-cellu mass, than has been possible by any method lose. By insufficient stirring in of air dur of manufacture heretofore practiced. Fur ing mixing over pressing in packing, or sub ther, by virtue of the use of the improved mission to a series of temperature changes, sodium nitrate in pelleted form, as erein the explosives noted are known to deteriorate before described, I am able to secure increased in the properties mentioned. It is assumed densities in gelignites and gelatin dynamites, that this is due to loss of aeration or the col without corresponding decrease of aeration. 85 lapse of the minute air cells. Density in I wish to specifically disclaim the use of am creases during deterioration also point to monium nitrate in pelleted form of the na ward this, ture of that disclosed in the patent to Obviously, spherical or semi-spherical par Symmes, No. 1,613,335, because such ammo ticles will not pack like a fine powder or ir nium nitrate yields a lower density than even regular particles, and automatically provide ordinary granular ammonium nitrate or sturdy walled air spaces in the explosives. Chilean sodium nitrate. The hollow nature of the pellets further pro Lower density is desirable in those explo vides such a condition. The result is an sives of the "permissible' type while gelatin aeration of the explosives which is main dynamites and gelignites from the very na 95 tained under very severe conditions and ex ture of their application require a high den cellent keeping qualities are effected. Since sity. The introduction of ethylene glycol di the explosives manufactured in accordance nitrate in the manufacture of dynamites has with this invention represent the greatest de tended to reduce their density and has been parture from the dead pressed phenomena a source of worry and trouble to explo 100 they will detonate with maximum orders of sive manufacturers. Consequently, any detonation and so show excellent propaga thing tending to further lower their density tion sensitiveness and rate of detonation con is to be avoided. ditions. Their resistance to loss of aeration It is understood that the invention applies will also keep them most effective in use only to gelatinous explosives, commonly 10s under conditions of hard tamping and high known as gelignites and gelatin dynamites. pressure, as in deep holes filled with water. They are very different from non-gelatinous There is actually provided a new form of dynamites in structure and in the effects of aeration to augment the aeration caused by various conditions upon them. stirring air into the colloided . It is further to be understood that the in The spherical or semi-spherical particles vention is not limited to the particular pro o will roll readily within the mass of gelatin, portions recited, but that it includes within as compared with fine powder or irregularly its, purview any composition coming within shaped particles. This tends toward easier either the terms or the spirit of the appended packing into cartridges and greater condi claims. 5 tions of softness and plasticity. Easier pack Having thus clearly set forth the essential ing into cartridges means less pressure ex features of the invention, and shown by ex erted and less loss of aeration, showing the ample, how it may be applied, I claim: interlocking nature of the effects. 1. Pelleted alkali metal nitrate ingelig nites and gelatin dynamites as herein 20 Also the spherical or semi-spherical parti scribed...... cles, most of which have no opening into the 2. Alkali metal nitrate in particles of sub hollow interior, present less surface to which stantially spherical form in gelignites and nitroglycerin may adhere, as compared to gelatin dynamites. particles of other shapes and fine powders, 8. Gelignites and gelatin dynamites which 125 This obviously presents the possibility of contain substantially spherical particles of preparing moist, soft, plastic masses of gela sodium nitrate. tin with less nitroglycerinthan usual. There 4. Gelatinous explosives which contain al is thus rendered possible the manufacture of kali metal nitrate which has been converted : lower strength, cheaper gelatinous explosives, to a spherical form from a molten condition, 30 1,778,718 5. A gelatinous explosive containing an alkali metal nitrate in particles of substan tially spherical form. 6. A gelatinous explosive containing an al pellets.kali metal nitrate in the form of distinct 7. A gelatinous explosive containing an alkalimetal nitrate in the form of hollow pel lets. o 8. Agelatinous explosive containing sub stantially spherical pellets of sodium nitrate. ... 9. A gelatinous explosive containing hol low pellets of sodium nitrate. 10. A gelatinous explosive containing hol slow pellets of an alkali metal nitrate of Sub stantially spherical form. 11. A gelatinous explosive of greatly in creased aeration characteristics, having as an ingredient thereof substantially spherical 20 hollow pellets of sodium nitrate. 12. A gelatinous explosive of greatly in creased aeration characteristics, having as an ingredient thereof substantially spherical hollow pellets of sodium nitrate in the form 25 produced by discharging molten sodium ni trate into the atmosphere. In testimony whereof I affix my signature.g ROY LINDEN HILL. 309

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