US1582273A - Method of blasting and apparatus therefor - Google Patents

Description

J. F. JOY

- l A ...Md f .www

April 27, 1926.V

METHOD OF BLASTING AND APPARATUS THEREFOR Filed Jan. 24. 1924 Patented pr. 27, 1926'.

UNITED STATES 1,582,273 PATENT oFFlcr..

JOSEPH F. JOY, PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO JOY MACHINE COM- PANY, OF PITTSBURGH,` PENNSYLVANIA, A CORPORATION OF DELAWARE.

METHOD OF BLASTING AND APPARATUS THEREFOR.

Application fue@ January 24, i924. 'serial no. 688,185.

Toull `whom it may concern.'

' Be it known that J osErH F. J or, a citizen of the United States, residing at Pittsburgh, in the county of Allegheny and Stato of Pennsylvania, has invented certain new and useful 'Improvements in Methods of Blasting and Apparatus Therefor, of which the following is a specification.

This invention relates to a certain new and improved method of blasting and appa ratus therefor, particularly useful in the mining of coal.

The primary object of the invention is, to greatly reduce the hazards of mining through the elimination of the use of blasting powder.

Another object is to `so disrupt the coal as to produce a larger percentage of lump coal and a smaller percentage of nercoal 4and dust, without the production of smoke, whereby a better quality of coalis produced and mine atmosphere is made more healthful.

- l/Vith the above general objects in view, and others that will become apparent as the 'nature of the invention is understood, the

same consists of the novel method and ap-v paratus hereinafter more fully described, shown in the accompanying drawing, and claimed. y l

In the drawing, wherein like reference characters indicate corresponding parts throughout the several views.

Figure l is a side elevational View of one form of apparatus constructed in accordance with the present invention, partly broken away and illustrating its use in a mine room,

Figure 2 is an enlarged fragmentary detail view, partly in side elevation and partly in section, showing the blasting nozzle in thel drill hole, and

Figure 3 is a diagrammatic plan View illustrating the tanks, pumps, and pipe connections thereto, Y.

Fig. 4 isa longitudinal section through a check-valve which is interposed in the air line leading to the blasting nozzle.

yIn the mining of coal, it is customary to undercut'the same as at 5 for a depth substantially equal to the width of the vein, after which a hole is drilled into the coal at an angle and at one ormore places above the undercut as at In order to Win this cut of coal, or to dislodge and disrupt the same `-suilciently to allow its removal, it has hereing up a non-expansible filidpressure in the shot holes, and as soon as this initial rent occurs a previously accumulated charge of expansible fluid under pressure, through automatic provisions, is permitted to How, into the rents or crevices created by the high pressure non-expansible fluid and, expanding therein, creates what may be termed an artilicial eX- plosion'.7 lVhen the latter occurs, the coal is sufficient-ly shattered, loosened and broken to allow its ready removal, and no smoke or fire and very little fine coal is produced.

A simple form of apparatus for carrying out the above method is shown in the drawing and preferably embodies a portable machine whiclrmay be readily moved from place to place. This machine, as shown, consists of a wheeled truck -7- adapted to run on the rails -8- .usually laid in the mine, which truck has an ai'r compressor -9- and a hydraulic pump -10- mounted thereon. An electric motor 1l-- is mounted on the truck between the air compresser and the hydraulic pump and is opermounted beside pump -9- and motor- -11-, and the pump -9-'discharges into v this tank 4 16- through the pipe -17-. The outlet v--18- of the pump'l0 is connected to the reservoir 141- by a piping -19- in which is placed a manually closed cut-oill valve 3lwhich valve is of a well-known type. The discharge line -21- connects with the outlet 1S- and extends to the forward end of the truck where it is provided with a cut-off valve -22-. The tank 1G-,- has an outlet 23- at its forward end lwhich is provided with aout-off valve Q4-i A pressure hose -2'5- is coupled with the outlet of tank -16-, while` a high pressure hose -26 is coupled to the discharge line -2l and to the lateral branch of a T-fitting -27-. The. inner end of a long bell-mouth nozzle or tube 2S- is coupled to the fitting 2T- and the remaining port of the latter is connected to the hoseby means of a conventional check valve --29-. As the hose 2 6- terminates for wardly of the valve -29-, the latter will be closed by the hydraulic pressure ahead of the same in the nozzle -28 but will be opened by the lesser pressure in the air hose -25- when the hydraulic pressure is relieved, as will presently become apparent.

In operation valve -31 is opened, the motor --11 is started and the valves -22- and -2lare closed, thereby causing the tank l6 to be filled with air under pressure. The nozzle -28 is then inserted into the hole -6 and securely packed as at -30 by suitable packing ma- .teriaL Valves 22- and 24- are now opened and valve 3lclosed and the nonexpansible fluid passes through the discharge line 2linto nozzle -28r and into the hole t3- ahead of said nozzle. ,The

continued operation ofpump l-l0- results in a high pressure of non-expansible fluid being built up in the hole 6* until an initial rent or fracture -32- occurs in the coal. It is to be understood, of course, that the high pressure of the. non-expansible fluid ahead of the check valve -29-, ,at this time, results in maintaining the check valve -29- closed. As soon as this initial rent or fracture occurs, the pressure ahead of check valve -29- is reduced and the latter is forced open, permitting the expansible fluid accumulated in tank -16- to rush throughnozzle -28- into the coal, creating an effect which may be termed fan artificial explosion, whereby the coal is 'sufficiently broken and shattered to permit its ready removal.

From the'foregoing description it will be seen that the invention resides primarily -in the use of a non-expansible fluid for creating an initial rent or fracture, followed by the use of an expansible fluid of a lower pressure whichacts upon `they enlarged cavity resulting from the initial rent. It is alsoapparent that the initial use of a non-expansible fluid, such as water, serves to seal the pores in the strata for reducing the leakage of air or expansiblp fluid that is subsequently rised. Furthermore, it is well-known that it is highly desirable to' moisten coal dust in the mines, and it is apparent that this result is obtained from the use of the present invention,.the'coa1 of said hole, means to supply a substantially strata' being impregnated to such an extent as to prevent the occurrence of floating coal dust in the mine.

I do not wish to be understood aslconlining my methodl or apparatus to the sole and specific purpose' of mining coal since it is equally applicable to, and efficient in, the blasting or disintegration of many other deposits of matter that is to be disrupted and broken up to facilitate its dislodgernent or removal.

That I claim as new is l. In an apparatus for blasting material in which a hole is drilled, means including a pump to build up a hydraulic pressure in the hole sufficiently to cause an initial rent or fracture in the material, and means including a second pump tosupply air under presure into the rent upon occurrence of the latter.

2. An apparatus for blasting material comprisinga nozzle adapted to be placed in a hole formed in the material and to receive a packing therearound when so placed, a portable truck-having hydraulic pressure building means and air .compressing means mounted thereon, flexible water and airconduits connecting said nozzle to said pressure building means and said air compressing means, and means to control the flow of the water and air to said conduits.

3. An .apparatus ifor blasting material comprising a nozzle adapted to be placed in a hole formed in the material and to receive a packing therearound when so placed, a portable truck having hydraulic pressure building means and air compressing means mounted thereon, flexible Water and air conduits connecting said nozzle to said pressure building means and said air compressing means, means to control the flow of the Water and air to said conduits, and a forwardlyopening check valve between the nozzle and theair conduit and rearwardly of the/connection of the water conduit to the nozzle.

4. -In an apparatus for blasting material, a nozzleV adapted to be placed ina hole formed in such material and to be placed in substantially air-tight relationto the wall non-ex ansible fluid under pressure into the hole t rough said nbzzle, and means to supply an expansible fluid under pressurev behind said non-expansible fluid.

5. In an apparatus for blasting material, a nozzle adapted to be placed in a -hole formed in such material and to be placed in substantially air-tight relation to the wall of said hole, mea-ns to supply a substantially non-expansble fluid under pressure into the hole through said nozzle, and means to supply an expansible fluid under pressure behind said non-expansible fluid, and a portable support for both said Huid supplying4 means.

6. In an apparatus for blasting material, a nozzle adapted to be placed in a hole formed in such material and to be placed in substantially air-tight relation t0 the wall of said hole, means to supply a substantially non-expansible Huid under pressure into the hole through said nozzle, and means to supply an expansible fluid under pressure behind said non-expansible fluid. and a portable support for both said fluid supplying means, said fluid supplying means including a flexible conduit connected to the nozzle and extending from'the portable support.

7. The herein-described method of blasting deposits of material which comprises the following steps: providingl expansive space adjacent the mass to be blasted, drillving into said mass, injecting a non-compres` sible fluid under pressure into the hole so drilled, continuing such injection to build up the resulting pressure until rupture of the adjacent mass is effected, then releasing into the mass so ruptured, a compressed expansible fluid whereby further rupture of said mass is produced.

In testimony whereof I hereunto aix my signature.

JOSEPH F. JOY.

Images