USRE5619E - Improvement in explosive compounds - Google Patents

Description

' UNITED STATES PATENT OFFIoE.

ALFRED NOBEL, or name, ennnanv, ASSIGNOR, BY MESNE Assren Y MENTS, TO THE GIANT-POWDER eonrauv, on sun FRAJNCISGQ-CAL.

IMPROVEMENT IN EXPLos vE communes.

Specification forming part of Letters Patent No. 78,317, dated May 26, 1868; reissue No. 5,619, dated I October 21, 1873; application filed October 14,1873.

To all whom it may concern:

Be it known that I, ALFRED NOBEL, of the city of Hamburg, in .the Empire of Germany, have invented an Improved Explosive Oompound, of which the following is a specification:

This invention relates to a new and useful combination or mixture of nitroglycerine with some absorbent substance, whereby the condition of the nitro-glycerine is so modified as to renderthe resulting explosive compound more practically useful and cflective as an explosive, and far more safe and convenient for handling,

y storage, and transportation than nitro-glyceri ne in its ordinary condition as a liquid. The inventiongonsists in combining or mixing withnitro- .glycerine some porous or absorbent substance,

which, being free from any quality which will cause it to decompose, destroy, or injure the nitro-glycerine, forms in combination with it, an explosive compound possessing certain. marked properties of great practical utility, which not only increase its eiiieiency but also obviate many of the serious practical objections to the employment of nitroglycerine as an. cxplosi 'e. Some of these peculiar properties of this mixtnre will be briefiy stated.

Nitro'glyccrine being a liquid, .i t is usually necessary, in exploding it as an explosive for blasting purposes, to place it in cases or cartridges. formed of paper, metal, or other substance, which-must, of course, be of somewhat smaller diameter than the bore-holes, as, it not so inclosed, the nitro-glycerine would permeate the seams of the rock and prove highly dangerous to the miner, on account of its liability to explode in subsequent drillings; but by means of this invent-ion the nitro-glycerine, being held in combination. with the porous or absorbent substance with which it is mixed, and then assuming the altered form of a powder or paste, remains in the bore-hole in which r ciency; The liability of fluid nitroglycerine to accidental explosion from agitation or corn 'cussion renders its handling and transportationvery dangerous. This danger is, however, almost entirely obviated by the use of the compounddescr-ibed in this specification, because when mixed with a suitable absorbent the'nitro glycerine is far less sensitive to shocks than whcn'in a liquid condition, so that it may be handled in mass, either loose or ,in packages, with impunity. So much is this the case that when this mixture is packed in a wooden case or box the inclosure may be knocked to pieces without danger of exploding its contents.

This invention, then, consists in mixing liquid nitro-glvcerinc with some solid (as dis tin gin shed from liquid or fluid) substance whic by will absorb and retain a suflicient amount of nitro-glycerine to form an efficient explosive. The substance which is believed to be the best adapted for this purpose is a kind of silicious earth, found in various parts of the globe, and known by the various names of silicious marl, tripoli, and rotten stone. The peculiar variety of this material best suited for this use is homogeneous, has a low specific gravity, and great absorbent capacity, and is generally con-iposcd of the remains of infusoria. So great is the absorbent capacity of this in fusorial earth that when in apulverized condition it will take up about three times its own' wei. ;;lit ot. liquid nitroglycerine, and still retain the form of a powder. Other porous substances, even. though they have less absorbent capacity, may be used, but in this case the OXldOhlYG strength of the powder will be diininishod owing to the smaller proportion oi."

vcrization or conuninution, and which will retain nitrog1 ycerine by absorption, may be substituted for iufusorial earth.

The relative proportion oi the ingredients used in making this new explosive compound will vary according to the absorbent capacity of the substance-mixed with the intro-glycerine, it being preferable in all cases, and this is the only limit, to use so much only of the liquid nitroglycerine as the absorbent substance will retain without liability to subsc- I-que'nt' separation by coi'npressiou or leakage.

\Vhere the absorbent used in a powdered con.- dition is iufusorial earth, a thin paste or semiliuid condition of the mixture is to be avoided.

The method of making this new explosive.

com pound with infusorial earth is as follows: The earth, being first thoroughly dried and pulverized, is placed in anysuitable vessel, and

" the nitro-glycerine is then gradually introdueed and thoroughly mixed with the pewdered earth, which is effected either by stirring with the naked hand or by. means' of any suitable wooden instrument, Worked either by machinery or by hand. here infusorial earth is used the proportions may be conveniently varied, from sixty parts, by weight, of liquid nitr'o-glycerine, and forty parts, by weight, of infusorial .earth, to seventyeightparts, by weight, 'of Iiit-ro glycerine and twenty-two parts, by weight, of infusoria-l earth, the former proportions forming, at ordinary tcmperatures,;

a dry'pulverulent mass, and. the latter a pasty mixture. These proportions may, however, be

varied outside of the limits above stated, it.

- a powder sufficiently dry at ordiuary'temperatures, and which is susceptible of compression to a specific gravity-nearly equa'l'to that of pure nitro-glycerine. 4

\Vhn the ingredients have been intimately mixed and thoroughly inco1poratedby stirring and kneading, the compound may be rubbed through a sieve made of hair, silk, or brass-wire, and any lumps which remain may be powdered by rubbing them, through the sieve with'a stiff-bristle brush. The powder is then ready for use, and may be packed in bulkin boxes, or compressed into cartridge-cases 'made'ot paper, of such convenient sizes as may be most in demand for blasting purposesa A greater or less degree of fineness ot'grain powder is used as the explosive.

may be given to the powder 'by'usinga fine orcoarse sieve. I

In using this improved explosive compound for blasting, it may be inserted into cartridge cases, as above stated, or without any inclosure or wrapping, as may be preferred For the best effect it shouldbe pressed firmly down so as to fill the borehole, whether in cartridge or not, a small quantity at a time with a wooden rod until it is firmly packed. If the cartridges are smaller than the bore thepressure will burst them, and allow the powder to spread laterally andfill the bore- It may be easily and efficiently exploded by means of an ordinary blasting-fuse inserted into the open end of a percussion-cap, the metallic edges of the cap being compressed or crimped tightly and firmly around the fuse, so as to hold it in place, with the end of the fuse in close contact withtliefulminate in the 'iercussion-cap. The capped end of the fuse is then inserted into the explosive powder, which is pressed closely around it in the bore-hole, and a tamping of sand or other suitable material may be pl aced.

above the charge of powder and pressed down upon'it. I

"The fuse thus applied is fired in the ordinary manner, and when the fire reaches the percussiou'ea-pit explodes, which'efi'ects the immediate cx flosion of the charge of explosivc compound. It is better touse a percussion-cap having a heavy charge of fulminate, in order to insure an explosion of the powder, al-- though. under favorable circumstances it might be exploded with an ordinary fuse without any cap; but this method is too uncertain to be re 7 lied upon.

For ordinary blasting, the bore-holes may be about one-half the size, and the charge of explosive compound about one-fifth the quantity that would be made use of when. gun

hat we claim as the invention of ALFRED NOBI+1L,'and desire to secure by Letters Patent in the name of THE GIANT-POWDER 00M- PANY and THE ATLANTIC GIANT-POWDER COMPANY, as assignees (through mesue assign.-

ments) of the said ALFRED NOBEL, ,is-

The combination. of nitroglycerine with infusorial earth, or other equivalent absorbentsubstance, as a new explosive compound.

n. s. eno. o. HIOKOX,

Pro-shim! of the Giant-Powder 00.

'J' it uesscs H. lrcnors, A. BLACK.