US1891500A - Explosive composition - Google Patents

Description

Patented Dec. 2% 3932 warren stares PATENT @FFEQE EDWIN H. B'U'BRQWS, F CLEVELAND, OEIO, ASSIGNOR 0F ONE-HALF T0 WOBTHINGTON HOYT, 0F CLEVELAND HEIGHTS, OHIO EXPLOSIVE COMPOSITION Ho Drawing.

This invention relates to new and useful improvements in explosive compounds and more particularly to an improvement on the explosive compound for which United States SLetters Patent were granted to Frank R. Burrows and Joseph G. Burrows, April 22, 1919, No. 1,301,646.

The object of the invention is'to provide an explosive compound of high power and J3 destructive strength and which at the same time will be safe to handle and can be economically produced.

A further object of the invention is to provide an explosive compound which will not 9 be subject to freezing, which can only be exploded by detonation and which will not give off injurious fumes when exploded.

Another object of my invention is to provide an explosive compound of such a char- 9 acter that repeated charges of the samemay be safely used without having to wait for the material which is being worked on to cool ofi.

Further advantages of my explosive compound will be fully set forth in the following specification. A

In carrying my invention into practice, I provide an explosive compound consisting essentially of the following ingredients or their 3 substantial equivalents, to wit:

The ingredients are mixed in an ordinary incorporating mill, the barium nitrate being first introduced and the mill kept in action 5 for a period of about minutes to affect its reduction to the desired degree of fineness, after which the ammonium perchlorate, the aluminum powder, the aluminum granules and the resin are introduced and the mass is 0 ground and agitated for a further period of Serial No. 534,710.

twenty minutes. The parafiin wax and the brown wax may be then added to the mixture either in a melted state or dissolved in a suitable volatile solvent.

From the mill, the compound thus prepared, is passed to a sifter consisting of a revoluble screen drum covered by a wire mesh cloth, through which the powder discharges as the drum revolves. A number of brassor other hard balls are placed in this drum to break up all hard lumps and to disintegrate all the material to the desired degree. The powder is then filled into paper cartridge cases, preferably, by a filling machine. The ends of the cases are then folded over and dipped in melted parafin. The explosive in the form of cartridges is then ready for use.

This explosive compound possesses great explosive power, is non-freezing and consequently the dangers experienced in the operations of thawing out other explosives are avoided. This compound is absolutely safe from explosion by attrition or friction or by fire or by blows or concussion from tools or the like. It does not give ofl any injurious gases as substantially all injurious gases are consumed in the explosive action. The explosive may be manufactured with absolute safety at all times and may be used in either wet or dry holes and will explode only by detonation, using a detonator of not less than N o. 6 strength. It may be simply and cheaply manufactured, allows holes to be charged and mis-fires to be treated without risk, and since it is not explosive by heat, a sprung hole "may be charged therewith without danger and without the necessity of waiting until the bore is cooled, thus obviating the loss of time and danger incurred in the use of ordinary explosives.

Through employing a high proportion of ammonium perchlorate and by substituting exceedingly fine powdered aluminum together with a small quantity ofresin for the alpha-trinitrotoluene,- of the Burrows patent heretofore referred to, I am able to provide an explosive compound of greater strength and very much safer to manufacture and op erate with than can be produced by follgwing the teaching of the said Burrows patent.

The use of fine powdered aluminum makes it possible to very definitely and positively control the explosive force and rapidity of action of the explosive compound. That is by slightly altering the proportion of the aluminum powder the compound can be readily adapted to various fields of operation. To those skilled in this art it is well known that an explosive compound suitable for use in gold mines would be very destructive and wasteful in coal mines. By changing the amount of my fine aluminum powder I can make my explosive compound so that it will have the proper explosive force and the required rapidity of action for any class of work. This cannot be as positively and readily done with alpha-trinitrotoluene without sacrificing the safety element.

The water-cooled process aluminum employed in this improved explosive compound is prepared by pouring the molten aluminum on to a rapidly revolving Wheel which dashes it in the form of a spray into cold water. This process produces large jagged-surfaced particles or granules and gives the cooled particles very sharp points or edges which render the material susceptible to rapid ignition and combustion. This material is then ground, or is ground during the opera tion, to pass through a screen having about 30 meshes per linear inch, the resulting par-'- ticles are porous and hence in a highly reactive state. Aluminum prepared in any other way does not ive, in explosive work, the complete satisfaction and advantage aiforded by the aluminum as above stated.

The form in which the aluminum is used inthis compound is of material importance, and when used in connection with the other ingredients set forth, provides a compound which possesses the desirable advantage before stated.

The high quantity of ammonium perchlorate used in my compound is very important. The ammonium perchlorate forms a perfect combination with the fine aluminum powder and the resin, and the intensity of the explosion is much greater than where a rela tively less quantity of ammonium perchlorate is employed with alpha-trinitrotoluene.

When this compound is exploded it gives olf a quantity of smoke of an absolutely harmless nature as the intensity of the explosion causes the consumption of all harmful gases. The compound has a very desirable and unique ripping action in blasting large masses of rock, and in the tests made, is found to be of greater disruptive strength than the explosive compound produced by the aforementioned Burrows patent formula.

What I claim is:

1. An explosive compound consisting substantially of 54 parts ammonium perchlorate 29% parts barium nitrate, 1% parts fine 1,ee1,5oo

EDWIN H. BURRows.