RU217631U1 - CHARGE FOR HYDRAULIC FRACTURING - Google Patents

Abstract

The utility model relates to the oil industry, namely to the means of influencing the bottomhole zone of production, oil, gas, exploration and injection wells for the purpose of gas-dynamic fracturing. The charge for hydraulic fracturing contains an unpackaged group of charge sections from solid fuel, suitable for combustion in water and water-oil environments, placed along the composite carrier rod. The charge sections are made with an axial channel. The configuration of the axial channel has a shape with a developed combustion surface. Said rod is installed with a gap in the axial channel. At the ends of the rod, upper and lower cones tightening the group of charge sections are installed. The diameter of the cones exceeds the diameter of the charge sections. Between the charge sections, centering rings are placed, made with an outer diameter exceeding the outer diameter of these sections. The cones are made with holes for the passage of combustion products. One of the sections is igniter and is connected to the power wire with the possibility of igniting the fuel of the charge sections. The igniter section of the charge is installed between the upper cone and the group of charge sections and is provided with an overlay on the side facing the upper cone. The overlay has longitudinal through stepped holes. Explosive cartridges with segments of detonating cords adjacent to their ends are installed in the wide part of the longitudinal through stepped holes. The cords pass through the narrow part of said stepped holes and blind holes made in the igniter section of the charge. A groove is made in the lining, in which a flat spring is placed, partially enclosing the rod with the possibility of interacting with the bodies of explosive cartridges. EFFECT: increased reliability of charge functioning. 2 w.p. f-ly, 4 ill.

Description

The utility model relates to the oil and gas industry, namely to the means of influencing the bottomhole zone of production, oil, gas, exploratory and injection wells for the purpose of gas-dynamic fracturing, which increases the flow of oil into the well.

One of the rational and effective methods of influencing the near-wellbore zone of a productive formation in order to restore conductivity and establish a reliable hydrodynamic connection between the well and the formation is the fracturing of the formation by the combustion products of the powder charge. Under the influence of liquid and gas pressure equal to or greater than rock, rocks are irreversibly deformed.

A number of designs are known for thermogasdynamic treatment of the bottomhole zone of a productive formation. Common to them is the presence of solid fuel blocks (one or more) lowered into the well with the help of a geophysical cable. These checkers are installed in the formation treatment interval, ignited with the help of an electrical impulse supplied from the wellhead through a geophysical cable. The positive effect is achieved due to the complex effect on the reservoir - high pressure and high temperature, created by burning charges. High pressure leads to fracturing of the formation in the form of its fracturing, and the high temperature of the combustion products helps to remove paraffins and asphaltenes that pollute the formation due to their melting. The combination of these factors provides an increase in the permeability of the reservoir.

Known charge unpackaged sectional for gas-hydraulic impact on the formation [RF patent No. 2178072, IPC E21V 43/263, pub. 10.01.2002 g], including an ignition unit, powder sections of an unarmored charge with an axial channel, the configuration of which has a shape with a developed surface, made of compositions that ensure combustion in water, water-oil and acid environments, placed along a composite carrier rod, at the ends of which upper and lower cones-centrators (couplings) that tighten a group of charge sections, the diameter of which exceeds the diameter of the charge sections, one or more powder sections are igniters, from which the main powder sections ignite. At the end of the igniter powder section in the groove there is an ignition unit connected to the power wire. Between the lower sleeve and the powder sections of the charge there is a diffuser to remove the gas flow. The sum of the flow sections of the diffuser holes and their location is designed in such a way as to provide a minimum mechanical load on the rod and ensure the maximum effect of hot gas on the formation. Between the upper clutch and the powder sections of the charge there is a linear expansion compensator for the powder sections of the charge, which also performs the function of an elastic preload of the charge. The upper end of the upper connecting rod is connected to the logging cable, and the lower end of the lower connecting rod is connected to an electronic unit for measuring the characteristics of the charge operation mode and the response of the bottomhole zone to gas-dynamic impact. The hollow channels of the rod and sleeves form an internal cavity of the charge, inside which a conductor with heat-resistant insulation is passed, connecting the electronic unit with the logging cable and the power wire of the ignition unit.

The known device provides for the creation of an uncased charge, which makes it possible to fracture the formation without violating the integrity of the casing, to monitor the operation of the charge in real time.

The disadvantage of this device is the low reliability of operation due to the fact that the full-bodied cone creates an obstacle to the passage of powder gases and the pressure pulse acting from above, the energy of which is then spent on shifting the charge down. Due to the extensibility of the geophysical cable, there is a high probability of the charge hitting the bottomhole, which leads to deformation of the bearing rods. This reduces the strength and reliability of the connection in the termination node.

This disadvantage is eliminated in a device called "Charge for hydraulic fracturing" [utility model patent of the Russian Federation No. 106305, IPC E21B 43/263, publ. 10.07.2011 g], containing an unpackaged group of charge sections made of solid fuel suitable for combustion in water and water-oil environments placed along the composite carrier rod, made with an axial channel, the configuration of which has a shape with a developed surface, in which the said rod is installed with a gap, at the ends of the rod there are upper and lower cones that tighten the group of charge sections, the diameter of which exceeds the diameter of the charge sections, centering rings are placed between the charge sections, made with an outer diameter exceeding the outer diameter of these sections, while the cones are made with holes for the passage of combustion products. One of the charge sections is igniter, connected to the power wire with the possibility of igniting the fuel of a group of charge sections. The ignition unit is made in the form of a nichrome spiral connected to the power wire, placed at the end of the charge section and fixed around its axial channel of a figured shape with the possibility of igniting the charge fuel along the surface of the axial channel. This device as the closest to the claimed taken as a prototype.

The disadvantage of the prototype is the low reliability of operation, due to the fact that the charge ignition unit, made on the basis of a nichrome filament coil, ignites the charge sections for several seconds and the ignition time is not controlled, which does not allow the effective use of these charges, including for the synchronous system. impact on the reservoir with several charges in the production of oil fields.

The technical result, which the proposed utility model is aimed at, is to increase the reliability of operation by increasing the reliability of ignition of the charge and reducing the ignition time.

The technical result is achieved by the fact that the charge for hydraulic fracturing, containing an unpackaged group of charge sections made of solid fuel suitable for combustion in water and water-oil environments, placed along the composite carrier rod, is made with an axial channel, the configuration of which has a shape with a developed surface, in which said rod with a gap, at the ends of the rod there are upper and lower cones that tighten the group of charge sections, the diameter of which exceeds the diameter of the charge sections, centering rings are placed between the charge sections, made with an outer diameter exceeding the outer diameter of these sections, while the cones are made with holes for the passage of combustion products, and one of the charge sections is igniter, connected to the power wire with the possibility of igniting the fuel of the charge sections, according to the utility model, the igniter section of the charge is installed between the upper cone and the group of charge sections and is provided on the side facing the upper cone with an overlay, with In this case, longitudinal through stepped holes are made in the lining, in the wide part of which explosive cartridges are installed with segments of detonating cords adjoining their ends, passing through the narrow part of these stepped holes and blind holes made in the igniter section of the charge, a groove is also made in the lining, in which a flat spring is placed, partially covering the rod with the possibility of interacting with the bodies of explosive cartridges.

Installation between the upper cone and the rest of the group of sections of the charge of the igniter section of the charge, which is provided on the side facing the upper cone with an overlay, where longitudinal through stepped holes are made, in the wide part of which explosive cartridges are installed with segments of detonating cords adjacent to their ends, passing through one the ends through the narrow part of the specified stepped holes, and the other ends placed in the blind holes made in the igniter section of the charge, allows you to create a stable and reliable charge ignition unit and achieve a reduction in the ignition time (within 100 μs), increasing the reliability of the device in the production of oil fields.

Placing a flat metal spring in the groove of the lining, partially enclosing the rod with the possibility of interacting with the bodies of explosive cartridges, ensures reliable contact of the electric blasting line running along the rod with explosive cartridges.

In addition, to achieve the symmetry of the ignition section of the charge, as well as for the completeness and speed of burning, the holes for the cartridges in the lining are oriented relative to each other at an angle of 150°±10°.

In addition, to ensure reliable fixation of explosive cartridges in the holes of the lining and prevent their axial displacement, the lining from the side of the upper cone is tightly closed with a lid.

Thus, the combination of all the above features creates conditions for improving the reliability of the device by increasing the reliability of the ignition of the charges and reducing the ignition time.

The presence in the claimed utility model of features that distinguish it from the prototype, allows us to consider it as corresponding to the condition of "novelty". The utility model is illustrated by drawings:

in fig. 1 shows a general view of the device;

in fig. 2 - multi-beam form with a developed combustion surface of the charge section group (section A-A in Fig. 1);

in fig. 3 - lining of the igniter section of the charge;

in fig. 4 - placement of explosive cartridges in the overlay (section B-B in Fig. 1).

In the drawings of FIG. 1-4, the following designations are accepted.

1 - composite bearing rod;

2 - charge sections from solid fuel;

3 - axial channel in the charge;

4 - centering rings;

5 - upper cone-centrator;

6 - lower cone-centrator;

7 - holes in cones;

8 - igniter section of the charge;

9 - power wire;

10 - overlay;

11 - through holes in the lining;

12 - explosive cartridge;

13 - detonating cord;

14 - blind holes in the igniter section of the charge;

15 - groove;

16 - flat metal spring;

17 - lining cover;

18 - holes in the cover.

The device is made as follows.

Charge for hydraulic fracturing (Fig. 1) contains placed along the composite carrier rod 1 unpackaged group of sections 2 charge of solid fuel suitable for combustion in water and oil-water environments. The composite rod ensures the integrity of the structure under mechanical and thermal loads during the combustion of the charge and when the device is lowered into the well and retrieved. The implementation of the carrier rod is composite, i.e. consisting of several parts, allows, by changing its length, to collect a charge from a different number of powder sections of the charge, while also simplifying the transportation of the charge to the place of operation in disassembled form. The length of the carrier rod 1 varies depending on the number of simultaneously installed powder sections of the charge. Section 2 of the charge is made with an axial channel 3, the configuration of which has a shape with a developed surface. The mentioned rod 1 is installed with a gap in the channel 3. The configuration of the figured axial channel 3 has a multi-beam shape with a developed combustion surface (Fig. 2), made in such a way that when collecting adjacent powder charge sections, these channels form a single central channel. Between the charge sections 2 there are centering rings 4, made with an outer diameter exceeding the outer diameter of these sections 2, which do not allow the charge sections 2 to move relative to each other and, in case of bending of the rod 1 in an inclined well, touch the walls of the casing string. At the ends of the rod 1, there are upper 5 and lower 6 cones that tighten the group of charge sections, the diameter of which exceeds the diameter of charge sections 2, which makes it possible to protect the charges from friction and impacts against the borehole walls. To ensure a minimum mechanical load on the rod 1 and ensure the maximum impact of hot gas on the formation, the cones 5, 6 are made with holes 7 for the passage of combustion products. One of the charge sections 2 - igniter 8 is connected to the power wire 9 with the possibility of igniting the fuel of the remaining sections 2 of the charge. The ignition section 8 of the charge is installed between the upper cone 5 and the group of sections 2 of the charge and has an overlay 10 on the side of the upper cone.

In the overlay 10, there are through stepped holes 11 along the rod 1, in the wide part of which two explosive cartridges 12 of the PGN-150 type are installed, oriented at an angle of 155 ° relative to each other to achieve the ignition symmetry of the charge section, as well as for the completeness and speed of combustion. To the end of each cartridge 12 adjoin segments of the detonating cord 13 passing through the narrow part of these stepped holes 11 and blind holes 14, made in the igniter section 8 of the charge. Also in the overlay 10, a groove 15 is made, in which a flat metal spring 16 is placed. cartridges.

The assembly of the device is carried out as follows.

Collect the components of the rod 1, the length of which depends on the number of sections 2 of the charge. Then the lower cone-centrator 6 is attached. Centering rings 4 are installed between sections 2, which provide thermal compensation of charges during expansion with heating and protect the ends of the charges from destruction during transportation of charges in the well. Then the igniter section 8 is installed, inside the holes 14 of which pieces of detonating cords 13 are installed with the protrusion of their ends by 10-15 mm. Then, a pad 10 with a spring 16 previously laid in the groove 15 is installed from above so that the ends of the detonating cords 13 fall into the narrow part of the hole 11 of the pad 10, and the end of the igniter section 8 of the charge fits tightly into the radial groove made in the end face of the pad 10. Next, two explosive cartridges 12 are installed in the wide part of the hole 11 of the lining 10, to the central contact of which the wires 9 of the electrical circuit are connected. In this case, the spring 16, partially enclosing the rod 1, is in contact with the bodies of explosive cartridges 12. Then, to ensure reliable fixation of explosive cartridges 12 in the holes of the lining 10 and prevent their axial displacement on the lining 10, a cover 17 is tightly installed, into the holes 18 of which electric wires are threaded from explosive cartridges 12. Top cone 5 is installed on top of the lining 10, the assembly is pulled together.

The device works as follows.

The device is lowered into the well perforation interval. At the command of the operator, the igniter section 8 is ignited by applying a high-voltage voltage pulse through the power wire 9 to explosive cartridges 12. The end wall of each cartridge 12 is initiated and thrown to the end of the segment of the detonating cord 13, which leads to its initiation. The process of detonation of segments of the detonating cord 13 is accompanied by the release of a shock wave from the side surface of the cord to the surface of the charge channels of the igniter 8 and the heating of this surface by the products of the explosion. As a result of heating and cracking of the walls of the igniter 8 charge, it ignites simultaneously through two channels, which propagates along the igniter 8 charge. The reliability of the operation of the device is achieved by reliable ignition of the powder charges 2, meeting the requirements of synchronous dynamic impact on the formation during the extraction of oil fields in order to intensify the flow of oil into the well.

The use of this device has been tested on wells. As a result, an increase in the functioning of the device, made in accordance with the claimed utility model, was confirmed.

So, the presented information testifies to the fulfillment of the following set of conditions when using the claimed utility model:

a device that embodies the claimed utility model in its implementation relates to the oil and gas industry, namely, to the means for preparing the extraction of oil fields, using the energy of combustion of solid explosive materials (fuels) to break oil and gas reservoirs with pressure pulses from powder gases;

a tool that embodies the claimed utility model in its implementation, is able to increase the reliability of the device;

for the claimed device in the form in which it is characterized in the formula of the utility model, the possibility of its implementation using the means and methods described in the application and known before the priority date is confirmed.

Therefore, the claimed utility model meets the requirement of "industrial applicability" under the current legislation.

Claims (3)

1. A charge for hydraulic fracturing, containing an unpackaged group of charge sections made of solid fuel suitable for combustion in water and water-oil environments placed along a composite carrier rod, made with an axial channel, the configuration of which has a shape with a developed combustion surface, in which the mentioned rod, at the ends of the rod there are upper and lower cones that tighten the group of charge sections, the diameter of which exceeds the diameter of the charge sections, centering rings are placed between the charge sections, made with an outer diameter exceeding the outer diameter of these sections, while the cones are made with holes for the passage of combustion products , moreover, one of the sections is igniter, connected to the power wire with the possibility of igniting the fuel of the charge sections, characterized in that the igniter section of the charge is installed between the upper cone and the group of charge sections and is provided on the side facing the upper cone with an overlay, while in the overlay longitudinal through stepped holes are made, in the wide part of which explosive cartridges are installed with segments of detonating cords adjoining their ends, passing through the narrow part of these stepped holes and blind holes made in the igniter section of the charge, also in the lining there is a groove in which a flat spring is placed , partially covering the rod with the possibility of interaction with the bodies of explosive cartridges. 2. Charge for hydraulic fracturing according to claim 1, characterized in that the holes for explosive cartridges in the pad are oriented relative to each other at an angle of 150 ^° ± 10 ^° . 3. Charge for hydraulic fracturing according to claim 1, characterized in that the pad on the side of the upper cone is tightly closed with a lid.

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