RU2173831C1 - Method for filling of boreholes with explosive and powder charges - Google Patents

Abstract

FIELD: mining industry, applicable for blasting by deep-hole charges at opencast mining of mineral resources. SUBSTANCE: V-or U-clamps are arranged and fastened on the surface of explosive and powder charges engageable with the walls of the bore-hole at its filling so that the clamp ends that are free from fastening form a contour around the charges, whose diameter does not exceed the borehole diameter, the charge is fed to the borehole, centered by the clamps, whose ends press it to the walls, and the charge is lowered, the borehole is filled with charges in the conditions of free fall, whose speed is slowed down by friction of the clamps against the borehole walls. Packs of film materials filled with liquid or gas for damping of impacts of the dropped charges are placed on the ends of the dropped charges. The safety of filling of boreholes with charges is provided by safe procedures making it possible to use the conversive explosive and powder charges for industrial blasts. EFFECT: enhanced safety. 2 cl, 3 dwg

Description

 The invention relates to blasting and is intended for the mining industry.

 It is known to fill vertical downhole wells by lowering on a flexible connection individual elements of an explosive charge (BB), disengaging them from a flexible connection, raising the connection and lowering the element of the next charge [1]. The complexity of the analog is obvious.

 It is known that wells are filled with powder charges by assembling and lowering the entire well charge on a flexible tape wound from two drums [2]. The tape surrounding the charge and lowered with it eliminates the friction of the charge on the walls of the well, ensuring safety.

 The prototype requires the design and manufacture of non-standard equipment, the purchase of an electric motor with a gearbox and a winch with a brake, which is feasible for large mining enterprises and impractical for small quarries.

 An object of the present invention is to fill wells with explosive and gunpowder charges in a manner that ensures the safety of their discharge into the well with the exception of any mechanisms and devices.

 The technical result is achieved by the fact that on the surface of explosive charges and gunpowder, which interacts with the walls of the well when filling it, V- or U-shaped brackets made of elastic materials are placed and fixed in such a way that the ends of the brackets free of attachment form around the charges a circuit whose diameter exceeds the diameter of the wells, when a charge is applied to the well, the ends of the brackets are pressed against the walls of the well during elastic deformation, the charge is centered in the well, which is filled in the mode of free fall of charges, ck which growth slows friction clamps of the borehole wall. At the ends of the discharged charges placed packages of film materials filled with liquid or gas.

 The brackets are fixed to the charge with tape - tape with an adhesive layer.

 The method is illustrated in the drawing, where in FIG. 1 and 2 show a diagram of a charge prepared for dropping into a well in two projections; in FIG. 3 is a diagram of a bracket. The following notation is used in the drawing: 1 - explosive or gunpowder charge, 2 - U-shaped bracket, 3 - V-shaped bracket.

 The staples are made of plastic or rubber. They are placed on a cylindrical surface of the charge with an adhesive coating on both sides, for example, an adhesive tape on cotton fabric with double-sided lubrication TU 38-105124-70. The tape is wrapped around the charge, glued to its cylindrical surface, and the brackets are pressed to the outer surface of the tape with an adhesive layer, gluing them. When filling wells with checkers of ballistic powders weighing 15-20 kg, the brackets are additionally fixed with a second tape with an adhesive layer on one side.

 On all charges, the rows of brackets are placed in two parallel tiers along the height of the charge (Fig. 1). In preparation for dropping the first charge, the brackets are grouped so that the horizontal projections of both rows of the bracket completely overlap the annular gap between the charge and the walls of the well. The foregoing is necessary for prophylactic treatment of the surface of the well and dropping into the bottom of possible pieces of rock - in order to prevent the pieces of rock from falling between the ends of the charges, which can violate the completeness of detonation of the borehole charge, especially consisting of ballistic gunpowder.

 Elastic-elastic staples are made thickened in the middle part with a smooth decrease in thickness to the ends, which will provide the elasticity of the end parts of the staples with an increase in resistance to further deformation with an increase in external influences.

 Before dropping the first charge into the well, a packet of film material filled with air is placed under it, the packet is glued with tape. When charging waterlogged wells at the lower end of the first charge, the bag of air is not placed.

 All subsequent charges, except the last, are discarded with packets of liquid or gas only at the upper end. At the end of the last charge, an intermediate detonator is fixed with means for initiating it.

 The staples can be made by molding or pressing from rubber or plastic gutters in the form of rings, followed by cutting into the staples of the required width. For use in winter conditions, it is preferable to fabricate rubber or frost-resistant plastic compositions; for other conditions to produce from the most economical raw materials, such as recycled polyethylene.

 The length of the discharge charge should exceed the diameter of the charged well by 1.5 times, preferably 2 times. When working with shorter charges, they should be duplicated, connecting the charges with the ends and fastening the connection with tape. The foregoing will eliminate the jamming of charges in the well during their free fall and will ensure reliable contact of the elements of the borehole charge at their ends.

 Packages made of film materials dampen shock of discharged charges, and staples exclude their friction against the walls of the wells, ensuring safety.

 The preparation of charges for dropping by the described techniques can be performed on a block prepared for explosive destruction, since it does not contain time-consuming operations.

Sources of information
1. SU 1518650, F 42 D 3/04, 10.30.1989.

 2. RU 2131108, F 42 D 1/08, 1997, BI, 1999, N 15.

 Ozhegov S. I. Dictionary of the Russian language: 70,000 words / Ed. N.Yu. Swedish -23rd ed. , rev. M.: Rus. lang 1990. p. 721 "BRACKET-1 A horseshoe-shaped instrument for measuring machine parts. 2. An angled iron strip for fastening wooden parts of a building 3. A metal strip curved in a semicircle serving as a handle at doors, chests."

Claims (2)

 1. The method of filling wells with charges of explosives and gunpowder by shielding inert materials of their surface, interacting with the walls of the well when filling, characterized in that V-or U-shaped brackets are placed and fixed on the surface of the charges in such a way that the ends are free from fastening the brackets form a contour around the charges, the diameter of which exceeds the diameter of the well, the charge is fed into the well, centered with brackets, the ends of which are pressed against its walls, and the charge is released, the well is filled in the free mode Drop charge-stand, which slow down the rate of the friction clamps on the borehole wall.  2. The method according to claim 1, characterized in that at the ends of the discharged charges place packages of film materials filled with liquid or gas.

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