US252250A - Blasting-powder - Google Patents

Description

' UNITED STATES Y PATENT @FFICE.

SVILLIAM R. QUIN'AN, OF SAN FRANCISCO, CALIFORNIA.

l BLAST'ING-POWDER.

srxorrrcnrron forming part of Letters Patent No. 252,250, dated January 10, 1882.

' I Application filed April 9, 1881. (No specimens.)

To all whom it may concern Be it known that I, WILLIAM R. QUINAN}, lieutenant in the United States Army, and a citizen of the United States, residing at the city of San Francisco, in the county of San Francisco and the State of California, have invented a new and useful High Explosive, of

t which the following is a specification,

My invention relates to the improvement of nitro-glycerine powders in regard to strength and safety and comparative freedom from noxious gases when exploded, my object being to produce a powder which possesses great power and is at the same time very safe to handle, transport, and use, and can be exploded in confined places with less inconvenience to the miner. When blastingpowders are made the admixture of nitro-glycerine-with inertabsorbents-such as kieselguhr-safety is attained at a great sacrifice of power. If an excess of nitro-glycerine is used with a view to greater strength, the powder itself becomes sensitive to blows and is liable to accidental explosion from the leakage of-nitro-glyceriue; and when blasting-powders are made by the admixture of nitro-glycerine with the ordinary oxidizing absorbents, though loss of power is partly obviated, there remain in such powders in varyingdegrees the same sensitiveness and liability to leakage. The absorbent which I use is a nitrocellulose made from wood pulp, sawdust, or other vegetable fiber by the action of sulpho-uitric acid. If the acids used are of commercial strength, the fiber should be sub- 3 5 jected to their'action for a few minutes only.

If they are diluted, the time should be increased in proportion to their dilution. Neither acid should contain more than two equivalents of water. The product is a low form of nitrocellulose, varyingin my experiments from onehalf to two-thirds the explosive strength of gun-cotton or trinitro-cellulose, measured by n free from impurities, the nitro cellulose would.

the pressure-gage. As I use it made from wood pulp it is a fine yellow substance very much resembling (except in color) the original wood pulp. The color I do not regard as an essential characteristic. If the acids used were probably be uncolored. It is capable of absorbing a very large-percentage of nitro-glycerine without leaking. The higher form, or the as its holding power is superior.

aboutfit'teen parts, by weight,of nitrocellulose with about twelve parts, by weight, of pulverizedchlorute or nitrate of potash, or its equivalent, and mix this with about thirty'two parts of nitro-glycerine. these materials produces the powder, which is yellow in color and dryish, holding the nitroglycerine in such thorough absorption that a heat of 120 Fahrenheit will not cause leakage. When first made this powder is quite safe against blows. At'terstanding a short time it becomes still more so, partly, from the more thorough absorption of nitro-glyeerine, but chiefly from the natural absorption of a small percentage of moisture from the atmosphere. The same effect may he arrived at di rectly in the manufacture by adding three per cent. of water to the other materials. More water may be added, producing greater insensitiveness; but it too much is mixed in, a stronger primer than the ordinary triple-force cap will be required to develop the fullstrength of the powder.

The action of the moisture or water is thus tween two hard surfaces the sudden conversion of mechanical energy into heat will cause explosion it the temperature of the explosive is sufficiently raised. The great specific heat of water prevents this dangerous elevation of temperature, as the waterabsorbs and renders latent the heat of percussion. Thus the moisture or water presentin this powder after manut'acture is a valuable agent in producing safety against blows. g

The powders made from chlorate and nitrate are very much alike in regard to safety against percussion. The chlorate-powder is somewhat stronger, but when in the loose state and dry it can be exploded by fire, whereas the nitratepowder is free from this danger. Both pow ders, when compressed into cartridges, are safe against fire. They burn somewhat like compressed guucotton, but more quietly.

I do not confine myself to the exactpropon tious given above. A larger proportion of ni- To get a powder of great strength I mix,

Thorough incorporation of is preferable,

so explained: When an explosive is struck be tro-glycerine can be safely held by the absorbent. The strength of the powder, however, is more directly dependent upon the relative proportions of the oxidizing agent and the nitrocellulose than upon the quantity of'nitro-glycerine present. if a smaller quantity of nitroglycerine be used, the. relative proportion of chlorate or nitrate to the nitro-cellulose should be lessened, the extremes being about twelve parts chlorate or nitrate to fifteen parts. nitrocellulose when fifty-five or more parts nitroglycerine are employed, and seven parts chlorate or nitrate to fifteen nitro-eellulose when the proportion of nitro-glycerine is less than ten per cent. When the higher form of nitrocellulose is used the proportion of nitrate or chlorate should preferably belesscned to about ten instead of twelve parts.

I am aware that Nobels blasting-gelatine is made by mixing nitrated cellulose with nitroglycerine and an oxidizing ingredient; but other and inert ingredients are added which reduce the explosive force of the compound and produce highly deleterious gases on explosion, and the proportion of nitrated cellulose is very small and undergoes by gentle heating a kind of solution in the nitro-glycerine, making ajelly-likc mass (not a powder) which is sensitive to percussion.

I am also aware that an explosive composition has been made composed of nitro-glycerine, nitro-ccllulose, and gunpowder; but in such case the nitrate of potash in the gunpowder is insufficient to oxidize the entire composition, being consumed by the other ingre-' dients of the gunpowder itselt -namely, sulphur and charcoal. Moreover, the two latter ingredients produce very deleterious gases on explosion. The composition I have-perfected, it will be observed, consists essentially of three ingredients, two of which are explosives and theother an oxidizing agent, which contributes to the total'explosive effect of the whole compound in the following manner: Upon explosion any carbon left from the nitroglycerine and nitro-cellnlose in a free state,

the ordinary conveniences of the powder form in other high explosives. It is the strongest blasting-powder of which I have any knowledge. It. is the safest strong powder of which I have any knowledge. It can be readily packed in cartridges of any size, and can be safely ram med into the bore-hole,givinggreater or less concentration of power according to the degree of compression. The moisture, to which the safety is largely due, is a stable quantity, and is firmly held by capillary attraction in the cartridges, so'that the powder is not subject to sudden changes of character from hygrome-tric or thermometric causes, leading to disasters in its use. So safe is it against blows that a cartridge torn to shreds by a charge from a shot-gun at a few paces willnot be exploded by the shock. The gases evolved on the explosion of this powder are less injurious to health.

What I claim,and desire to secure by Letters Patent of the United States, is-

1. A high explosive powder composed of nitro glycerine, nitrocellulose, and chlorate (-or nitrate) of potash. v

2; A high explosive powder composed of nitroglycerine, nitrocellulose, and chlorate (or nitrate) of potash, in the proportions substantiaily as setforth.

"WM. RI QUINAN.