RU2182969C2 - Method of flameless breakage of solid bodies and device for its embodiment - Google Patents

Abstract

FIELD: technology of blasting operations, particularly, flameless blasting of rocks. SUBSTANCE: essence of the invention consists in that rapid heating of substance placed into blasthole for change of substance state of aggregation and building up of high pressure (up to 1500 atm) is effected by short-circuiting of graphite rod or cylinder placed into substance with current of chemical storage battery. The method is realized with use of device including a metal body filled with water, membrane and nozzle plug. The body accommodates two electrodes and a graphite tube which is pressed into electrodes. A copper insulated cable is connected to plus electrode through internal cavity of the graphite tube. Whole system is connected to a voltage source. EFFECT: higher safety of operation with flameless breakage of solid bodies. 2 cl, 1 dwg

Description

1. The technical field to which the invention relates.
The invention relates to techniques for blasting, in particular to flameless rock blasting.

2. The level of technology
A known method and device for flameless blasting through cartridges of cardox or hydroxide, the action of which is based on the instantaneous transition of the liquid charged by the cartridge (liquid carbon dioxide or water) into a gaseous state. Moreover, in hundredths of a second, a huge increase in volume occurs with increasing pressure up to 700-1500 atm, and the blasting is carried out by burning a heating element (10% naphthalene and 90% potassium chlorate), ignited by means of an electric igniter (Technical Dictionary, M., Gonti NKTP USSR, 1939, p. 124).

 The closest analogs are: according to the method, a technical solution, according to which a hole is drilled and a liquid substance is placed in it, for example water, which changes its state of aggregation by turning it into steam when it is heated using electric current to a high temperature and pressure sufficient to break solid body (see A.S. USSR 581276).

 The closest technical solution regarding the object of the invention is a “device”, a device for flameless destruction of solids, including a metal casing filled with water with a membrane and nozzle plug, which can pass high pressure steam, two electrodes placed in the casing (see.with. 34489).

 The specified method and device are difficult to operate, associated with the use of explosive and fuel substances. The objective of the invention is to remedy these disadvantages.

3. The invention
The problem is solved as follows.

 The method of flameless destruction of solids consists in drilling a hole with a diameter of 55-60 mm and a length of up to 3 m in a solid, inserting a durable steel cylinder filled with water, inside which a graphite pipe is located; the terminals from the chemical current accumulator are connected to it and the cylinder is closed with a nozzle plug. Using a trigger switch, a voltage of 25 V is supplied to the graphite pipe and a short circuit current is generated in it for hundredths of a second. A graphite pipe is sublimated at high temperature, and water is instantly converted to a gaseous state with a huge increase in volume and, accordingly, pressure. The gases formed after breaking through the membrane are discharged through the nozzle plug into the hole and the solid is destroyed at a pressure of 700-1500 atm.

To implement the method of flameless blasting, a device is used that includes a metal housing configured to fill with water with a membrane and a nozzle plug, which is capable of passing high pressure steam, two electrodes placed in the housing, while a graphite tube with a cross section of 70-80 mm ^{2 is} placed inside the housing and 90-110 mm long, which is pressed into the indicated electrodes, and a copper insulated cable is connected to the positive electrode through the internal cavity of the graphite pipe, which, together with the cable, connects annym, negative electrode are connected through the trigger with the chemical battery current with a voltage of 25 V and a capacity of 100 A • h, and the housing is automatically positioned slidding metal supports having the ability to hold the device in the hole at the moment of fracture flameless solid.

 A device for flameless destruction of solids is shown in the drawing.

 It consists of the following elements: a metal housing 1 with a membrane 2 and a nozzle plug 3, inside which a graphite tube 4 with two electrodes 5 and 6, in which it is pressed, is placed. An insulated copper cable 7 is connected to the upper positive electrode 5 through the internal cavity of the pipe, and cable 8 is connected to the lower electrode 6. Automatically sliding metal stops 9 are located in the lower part of the housing 1.

 The device operates as follows.

Open plug 3 and pour 1200 g of fresh water into the case, insert the device into the hole to a depth of 3 m. Connect the cables 6 and 8 to the trigger switch and the battery voltage of 25 V and a capacity of 100 Ah. The trigger is turned on and the graphite pipe 4 is sublimated under a short-circuit current at a temperature above 3500 ^o C, while water is converted into steam at a pressure of 700-1500 atm, bursting the membrane 2 and, under the action of high vapor pressure passing through the nozzles of the plug 3, destroy the solid for example a coal seam. To keep the device in the hole during a flameless explosion, the stops 3 are automatically set apart in a position perpendicular to the longitudinal axis of the device.

Example (calculated)
We take a chemical battery of the tank type with a voltage of 25 V and a capacity of 100 A • h, capable of doing 2500 W • h or 2150 kcal, which allows 4 kg of water to be converted into steam, i.e. make about 20 turns on the device.

With one switch on, we perform work equal to 125 W • h in 0.05 s, developing a maximum power of 9-10 ⁶ W. In this case, the short circuit current of the graphite pipe is increased to 360,000 A with an electrical resistance of the graphite pipe 100 mm long equal to 0.00007 Ohms, which allows the use of a graphite pipe with an external diameter of about 14 mm and an internal diameter of 10 mm, i.e. section equal to 76 mm ² .

 The technical result consists in creating safe working conditions by eliminating the use of explosive substances and using automatic stops that hold the device in the hole at the time of a sharp increase in pressure.

Claims (2)

 1. A method of flameless destruction of solids, according to which a hole is drilled and a liquid substance, for example, water, is changed, which changes its state of aggregation by turning it into steam when it is heated using electric current to a high temperature and pressure sufficient to destroy a solid characterized in that the heating of the liquid substance is carried out by short-circuiting and sublimating a graphite rod or pipe placed in this substance. 2. A device for flameless destruction of solids, including a metal housing configured to fill with water with a membrane and a nozzle plug having the ability to pass high pressure steam, two electrodes placed in the housing, characterized in that a graphite pipe with a cross section of 70-80 mm is placed inside the housing ² and a length of 90-110 mm, which is pressed into the said electrodes, while to the positive electrode through the interior of the graphite tube is brought insulated copper cable, which together with the cable connected th, negative electrode 25 through the trigger with the current voltage connected to the chemical battery B with a capacity of 100 A • h, and the housing is automatically positioned slidding metal supports having the ability to hold the device in the hole at the moment of fracture flameless solid.