RU117499U1 - WELL PUNCHING DEVICE - Google Patents

Abstract

A device for perforating a well, including a hollow cylindrical body made in the form of a truncated cone and having a thread on the inner surface in the upper part and covered with a ball valve in the lower part, and in the middle part of the hollow cylindrical body there are stepped radial holes with special electrodes installed in them, in this case, each special electrode has a tubular structure with a diameter smaller at the outlet than at the inlet, and an annular protrusion is made on its outer surface, abutting against the step of the radial hole, and local dielectric spacers are installed on the outer end and the outer surface of the special electrode, and between the special dielectric elements are installed with an electrode and steps of a radial hole - an angle bushing, a cylindrical bushing and a ring, and a return spring is installed on the outer surface of a special electrode, pressed through the ring by a nut, and between the nut and the end face of the cylinder A graphite brush is installed in the ring, which connects a special electrode, which is the cathode, through an electrically insulated cable to the negative pole of the current source, while the anode is a casing connected to the positive pole of the current source.

Description

The utility model relates to the oil and gas industry and is intended for electrochemical perforation of casing strings during the construction, operation and overhaul of wells. Analysis of the existing level showed the following:

Known devices for mechanical perforation of casing strings (clause of the Russian Federation No. 2070279 "Device for creating perforation channels in the casing string" from 09/08/1994, class E21B 43/114, published on 12/10/1996; clause of the Russian Federation No. 2105137 " A device for perforation of a wellbore "dated May 14, 1996, according to class E21B 43/114, publ. February 20, 1998, etc.). The disadvantages are: the complexity of the design of the devices, as well as the formation of residual stresses in the pipe wall. In addition, when milling, the drainage channels in the borehole wall are not deep enough, since this is limited by the diameter of the cutter. Jamming of cutters and wedges in the body of casing is possible.

Known devices for hydraulic and hydro sandblasting perforation (and.with. No. 170889 "Hydraulic anchor-punch" from 07/17/1963 according to class E21B 43/114, publ. 05/11/1965; A.S. No. 697697 "Perforator" from 01/13/78, according to class E21B 43/114, publ. 11/15/1979, etc.) The disadvantage is the rapid wear of the equipment.

A device for thermal perforation (PN Lavrushko and others. The operation of oil and gas wells. - M .: Nedra, 1971. - p.29), which use a laser beam to form holes in the casing. The disadvantage is the large thermal impact on casing and their weakening, as well as the complexity of the equipment.

A device is known for electrochemical perforation of a pipe section in a well (RF Claim No. 2414588 “Method for perforating a pipe section in a well and a device for its implementation” dated 04.09.2009, class E21B 43/11, published on 03.20.2011) The disadvantage of this device is the design complexity, due to the large number of nodes and parts, leading to an increase in dimensions and mass of the device. So, the device contains a sensor for controlling the creation of holes in the pipe, but to fix the end of the process of electrochemical perforation, there is a moment of sharp decrease in electric current that is used, since the electrically conductive tube section of the electric circuit disappears. The entire process of electrochemical perforation is monitored and controlled through a ground control point, which provides for the presence of premises, expensive equipment, etc.

The technical result consists in simplifying the design of the device, reducing the cost of its manufacture and metal consumption, expanding the arsenal of devices designed to conduct gentle electrochemical perforation of casing strings.

The technical result is achieved using the proposed device for perforation of a well including: a hollow cylindrical body made in the form of a truncated cone and having a thread on the inner surface in the upper part; blocked by a ball valve at the bottom; In the middle part of the hollow cylindrical body, stepped radial holes are made with special electrodes installed in them.

Each special electrode has a tubular design with a diameter smaller at the exit than at the inlet;

on its outer surface, an annular protrusion is made, abutting against the step of the radial hole;

local dielectric gaskets are installed on the outer end and the outer surface of the special electrode, and dielectric elements are installed between the special electrode and the steps of the radial hole - a corner sleeve, a cylindrical sleeve and a ring;

On the outer surface of the special electrode, a return spring is installed, preloaded through the ring with a nut.

A graphite brush is installed between the nut and the end of the cylindrical sleeve in the ring, connecting a special electrode, which is the cathode, through an electrically insulated cable with a negative pole of the current source;

the anode is a casing connected to the positive pole of the current source.

Thus, the claimed technical solution meets the condition of novelty.

The design of the claimed device is illustrated by the following drawings:

figure 1 presents a longitudinal section of the device;

figure 2 presents a cross section aa;

A device for perforating a well comprises a hollow cylindrical body 1 with a through axial channel 2. In the upper inner part, the hollow cylindrical body 1 is made in the form of a truncated cone and has a thread for connection to a tubing. A ball valve 3 is installed in the lower part of the hollow cylindrical body 1, in the through axial channel 2. In the middle part of the hollow cylindrical body 1 there are stepped radial holes 4 in which special electrodes 5 are installed. Their number is determined by the inner diameter of the casing pipe and technological operations. Each special electrode 5 has a tubular design with a diameter smaller at the exit than at the inlet. On the outer surface of the special electrode 5, an annular protrusion 6 is made, abutting against the step of the radial hole 4, restricting the movement of the special electrode 5 inside the hollow cylindrical body 1. Local dielectric spacers 7 are installed on the outer end and the outer surface of the special electrode 5 to provide the necessary interelectrode gap, in order to prevent short circuit. Between the special electrode 5 and the steps of the radial hole 4, dielectric elements are installed: a corner sleeve 8, a cylindrical sleeve 9 and a ring 10, which provide electrical isolation of the special electrode 5 from the hollow cylindrical body 1. A return spring 11 is installed on the outer surface of the special electrode 5, ring 10 with nut 12, which secures the special electrode 5 in the stepped radial hole 4. Between the nut 12 and the end face of the cylindrical sleeve 9 in the ring 10 is installed g rafite brush 13, which connects a special electrode 5, which is the cathode, through an electrically insulated cable 14 with a negative pole of the current source mounted on the surface (not shown in the figure). The casing 15 is an anode and is connected to the positive pole of the current source.

The device operates as follows.

To conduct the process of electrochemical perforation of the casing 15, the device on the tubing is lowered to the depth of perforation of the well. The insulated cable 14 is connected through a graphite brush 13 to a special electrode 5 (cathode) and the negative pole of the current source mounted on the surface. The casing 15 (anode) is connected to the positive pole of the current source. The power source is off. By means of the return spring 11, special electrodes 5 are pressed inside the hollow cylindrical body 1. When the device reaches the required depth, the electrolyte is fed through the axial channel 2 under special pressure through special channels 5. The pressure created by the electrolyte column affects the internal area the end face and the inner cavity of the special electrodes 5, overcoming the force of the return springs 11, moves the special electrodes 5 to the extension, which are pressed against the inner surface ty casing 15 (Fig.1). Turn on the current source. When electric current flows, anodic dissolution of the casing material 15 occurs. Special electrode 5, as the substance of the casing 15 dissolves, deepens into the wall of this pipe and gradually passes through it, forming a hole in the shape of the electrode. The moment of hole formation in the casing 15 can be detected by a noticeable decrease in electric current, since the area of the anode dissolution decreases. At this moment, the current source is turned off, the pump unit is switched to a different operating mode: a pressure is created at which a hydromonitor effect will appear, that is, the destruction of cement stone and rock behind the casing 15 and the formation of a perforation channel. The high pressure of the liquid column will hold the special electrodes 5 in the extended position in the hole of the casing 15, preventing the movement of the device. After the formation of perforation channels, the flow of fluid is stopped. The pressure in the internal cavity of the special electrodes 5 drops, and they, under the action of return springs 11, return to their original position.

Using tubing, the device is moved to a new perforation site and the process is repeated. If several rows of electrodes are installed in the device, this will accelerate the process of perforation of the casing strings, since more perforation channels will be performed in one cycle.

The proposed utility model meets the condition of patentability, as it is new and has industrial applicability.

Claims (1)

A device for perforating a well, including a hollow cylindrical body made in the form of a truncated cone and having a thread on the inner surface in the upper part and blocked by a ball valve in the lower part, and in the middle part of the hollow cylindrical body there are stepped radial holes with special electrodes installed in them, each special electrode has a tubular design with a diameter smaller at the exit than at the entrance, and an annular protrusion is made on its outer surface, I abut go to the step of the radial hole, and local dielectric gaskets are installed on the outer end and the outer surface of the special electrode, and dielectric elements are installed between the special electrode and the steps of the radial hole - a corner sleeve, a cylindrical sleeve and a ring, and a return spring is installed on the outer surface of the special electrode, preloaded through the ring with a nut, and between the nut and the end of the cylindrical sleeve, a graphite brush is installed in the ring connecting the specialist ny electrode being the cathode through the electrically insulated cable to the negative pole of the current source, wherein the anode casing is connected to the positive pole of the current source.