DE2405571A1 - METHOD OF FILLING DRILL HOLES - Google Patents

Description

WesseI ing, January 31, 1974. VP / Dr Sch-B. / KI.

Our reference: UK 285

Procedure for filling boreholes ***

Various types of trimmings have been proposed to improve safety during blasting operations in mining. So for a long time d .r use of plastic Besatzgut such as mud or clay, known. It has already been described to press this material into the borehole under pressure (DT-PS 9527Ö1). Later it was proposed to replace loam or clay for better dust control with high-water jelly, so-called pastes, which should be pressed into the boreholes. Since it was deemed necessary to fill the free borehole space as completely as possible, paste was first filled into the depth of the borehole and the explosive cartridges were pressed into this filling (DT-PS 1 105 7 S3) - however, these ways of working did not Tried and tested, since there was a risk, especially if the filling mass was pressed between the explosive charges, that a proper detonation of the charging column would be disturbed, if not even prevented. For this reason, water and paste in particular filled into elastic plastic sleeves (cartridges) have become established in recent times. However, efforts are now being made in explosive work, especially in mining, to use explosive cartridges with a larger diameter. Correspondingly, boreholes with a larger diameter than previously usual are also required, and for these the usual loading cartridges are generally no longer sufficiently effective.

It has now been found that the paste is not only used in stocking cartridges

filled, but can also be used directly as a trim,

without fear of disturbing the detonation of the explosive charge

ten is. Accordingly, the inventive method for

509833/0109 ~ ² ~

- · 2 - -UK 285-

characterized ßesetzen of explosive charges in mining with water-containing gel-like paste by the paste dad by introducing d r explosive charges in a jet of air or of inert gas in the form of fine particles is sprayed into the wellbore. In contrast to the previous pressing in or pressing in of the plastic trim into the bore hole, the disadvantages mentioned above do not occur when the paste trim is introduced according to the invention. The explosive charge is first introduced into the borehole in a known manner and then the remaining borehole space is completely or partially, depending on the depth of the borehole, filled with a paste with a high water content. It must be ensured that the water content in the paste is sufficient for an optimal effect and that sufficient containment of the explosive charge is achieved. Under these conditions, the trim according to the invention provides a high level of security. The usual gelatinous pastes with a high water content, for example 85 % and more, as can be formed, for example, with the aid of methylene IuI loop or water glass, can be used. A spray of the highly water-containing paste into the borehole can be made with the known devices. Expediently, compressed air can be used as the conveying jet for the paste particles, since this is sufficiently available from the compressed air network at the points of use. Of course, it is also possible, if necessary, to work with an inert gas, for example nitrogen, as the carrier medium. The optimum setting of the ratio of gas to paste in consideration of the pressure, for example, of the available compressed air, d r consistency of the paste and the desired fineness of the paste particles may be carried out without difficulty. This fineness is to be chosen so that a safe transport of the paste particles in the air jet to the explosive charge is guaranteed. In addition, the paste that is sprayed in has such a consistency and strength that it does not emerge even in steep or vertical boreholes. Such sprayed paste further has the advantage that (i properly they can be used freely in all operations occurring in the drilling Iochdurchmesserη. The water content of each hole assembly is substantially greater than for all other types of fill.

509633/0109 -3-

- 3 - -UK 285-

The spraying of paste is easier and the filling is done faster than with the usual types of stocking «So it is associated with time savings. Of course it is possible with the help of a hose or pipe made of non-sparking Material spraying the paste from the explosive charge to the borehole mouth and so the borehole completely or partly to be filled with paste, even with large bores with e.g. 60 mm diameter, in which several explosive cartridges of 30 mm diameter were filled, could with inventive Introducing the paste an excellent dust suppression The detonations went perfectly.

In the figure is one of the possibilities according to the invention for Occupation of explosive charges shown schematically.

The pressure vessel 1 contains a paste filling filler 2. A jet of compressed air is sent through the nozzle 3, which entrains fine particles of the paste. The strength of the air jet and the pressure in the container are adjusted with the help of valves 4 and 5 as required. A sufficient quantity of the finely divided paste is injected into the borehole 9 through the hose 6 and the pipe 8, which is provided with a regulating valve 7. In the borehole are previously the. Explosive charges 10 have been introduced.

$ 09333/0109

Claims (1)

- 4 - -UK 285- Claim: Process for the occupation of explosive charges in mining with hydrous gel-like pastes, characterized in that the paste is made in a jet after the introduction of the explosive charges Air or inert gas is sprayed into the borehole in the form of fine particles will.