RU2534781C1 - Well strainer cleanout device - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: device comprises a source of acoustic vibrations installed inside the well strainer and coupled to the computer by a logging cable. A resonator is suspended at a logging cable near the source of acoustic vibrations while the source of acoustic vibrations is designed to change pulsation frequency for automatic setting of resonant frequency equal to the resonator frequency.

EFFECT: raised efficiency of cleanup and reduced time.

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Description

The invention relates to the oil and gas industry, is specifically intended for cleaning downhole filters.

It is known that well filters become clogged during operation (mudding occurs) and the well flow rate decreases several times.

Methods for cleaning downhole filters can be divided into two groups:

- purification of asphalt-resinous and paraffin hydrate deposits (soluble),

- purification of solid mechanical deposits (sand, clay, dolomite and other insoluble impurities).

In the first case, heating or solvents are used, and in the second, mechanical cleaning or wave (acoustic or hydraulic action).

A known method and device for cleaning the downhole filter according to the patent of the Russian Federation for the invention No. 2332560 ^x IPC E21B 43/00, publ. August 27, 2008

The downhole filter with the cleaning function is made in the form of a pipe with nipple threaded sections, one of which has a coupling and with holes on the side of the pipe. The filter element is installed concentrically to the pipe. The filter element is made in the form of two electrodes isolated from each other by means of a grid of non-conductive material. The electrodes are made in the form of a metal mesh and have the ability to connect to a source of electricity. The energy source is placed on the surface or made autonomous, for example, in the form of a battery of batteries or an electric generator and installed inside the downhole filter. The technical result is an increase in well production due to periodic cleaning of the filter element.

The disadvantages of this technical solution are the ability to clean only from tar and paraffin deposits and the need to perform the supply of electricity to a great depth.

A known method and device for cleaning a downhole filter according to the patent of the Russian Federation No. 2382178, IPC E21B 37.08, publ. 09/27/2009

A device for cleaning a downhole filter includes an oscillator installed in the housing, and means for delivering an oscillator to the bottom of the well and supplying electricity. A geophysical cable is used as a means of supplying electricity. The means of delivery of the oscillation generator contains an electric motor with a hydraulic propulsion. The electric motor and oscillation generator are installed in a sealed enclosure. The hydraulic propeller is made with two propellers connected to the electric motor through a transmission mechanism to allow rotation in opposite directions. The technical result is the provision of cleaning the downhole filter and delivery of the cleaning device to the horizontal section of the well, preventing twisting of the geophysical cable due to rotation of the device.

Disadvantages - a complex and expensive delivery device, the presence of a multi-kilometer geophysical cable, the length of the process of cleaning downhole filters.

A known method and device for cleaning a downhole filter (self-cleaning downhole filter) according to the patent of the Russian Federation for invention No. 2338871, IPC E21B 49/08, publ. 01/09/2007

This invention can be used in gas production and filtering water from sand. The self-cleaning well filter is made in the form of a pipe with nipple threaded sections, one of which has a coupling, and with holes on the side surface of the pipe, the filter element concentrically mounted on it. An insulated winding is installed in the filter element, which can be connected to an autonomous energy source, for example, a battery of power elements or an electric generator installed inside the downhole filter. The technical result is to increase the flow rate of the well due to periodic cleaning of the filter.

The disadvantage is the need to periodically change the power elements installed inside the downhole filter due to clutter of its internal section.

The known method and device for vibroacoustic impact on the formation according to the patent of the Russian Federation No. 2129659, IPC E21B 43/00, publ. 01/27/1999

The method consists in the wave action on the column of flushing fluid inside the downhole filter.

The device contains a ground power and control panel with a power rectifier. The high-frequency generator module comprises a frequency driver stage unit, a power amplifier unit, a load matching unit, and a signal modulation unit. The ground electrical connector is communicated through the power cable with the electrical connector of the downhole vibro-acoustic device. In the housing of the latter there is a vibro-acoustic emitter module. The device is additionally equipped with a safety unit, a control rectifier unit, a signal modulation control unit, a signal modulation indication unit, a resonance chamber module, formed by two ends overlapping the cavity of the downhole vibro-acoustic device and its body. The high-frequency generator module is located in the body of the downhole tool and is equipped with a frequency filter unit and a load matching control unit, the vibro-acoustic emitter module is equipped with at least two electro-acoustic transducers, the upper and middle electro-acoustic transducers being rigidly connected respectively to the upper and lower ends of the resonance chamber module with her outside. The device is implemented in the form of two small ground units and a downhole vibro-acoustic device. The use of the invention increases the efficiency of the device and its reliability in operation due to the use of a direct current device power supply and controlled matching of radiation with the well environment.

The disadvantages of the method and device are the low efficiency of the cleaning process and its duration. This is due to the fact that the source of the wave action is located deep inside the well, making it difficult to supply energy to it and control it. A special electronic device must be developed for control. Long-term cleaning of the downhole filter leads to a decrease in the time of operation of the well and a decrease in the total flow rate of oil (gas).

The objective of the invention is to significantly improve and speed up the cleaning of the downhole filter.

The solution of these problems was achieved in a downhole filter cleaning device containing an acoustic vibration source installed inside the downhole filter and using a geophysical cable connected to a computer, characterized in that a resonator is suspended on the geophysical cable near the acoustic vibration source, and the acoustic vibration source is configured to changes in the ripple frequency to automatically adjust the resonant frequency equal to the resonator frequency. The invention is illustrated in figure 1 ... 4, where:

- figure 1 shows a diagram of a device,

- figure 2 shows the design of the downhole filter,

- figure 3 shows a longitudinal section of a filter element,

- figure 4 shows a cross section of a filter element.

The device for implementing the method (figure 1 ... 4) is intended for cleaning the downhole filter 1, which contains a housing 2 with perforation 3, a sleeve 4 and a nipple 5, a filter element 6 (for example, a mesh or wire). Figures 2 and 3 show a variant of the wire filter element 6, which contains stringers 7, by welding 8 attached to the body 2, and wire 9, by welding 10 attached to the stringers 7. Between the body 2, stringers 7 and wire 9 are formed drainage cavities 11, which perforation 3 communicate with the cavity 12.

The downhole filter 1 contains at least one resonator 13 mounted concentrically to the housing 2 and having a housing 14 and a cavity 15, which through holes 16 communicates with the cavity 12. The resonator 13 is suspended from the geophysical cable 18 to the geophysical cable 18 or to the source of acoustic vibrations 19 , which is suspended on a geophysical cable 18 (figure 1).

The downhole filter 1 (FIGS. 1 and 2) is installed on the tubing string 20 inside the casing 21 in the area of the oil reservoir 22 located in the ground 23. This device contains a reservoir 24 for storing the flushing fluid, to which a low pressure pipe 25 is connected, having on the one hand, a filter 26, and on the other, a pump 27 with a drive 28. A feed pipe 29 is connected to the output of the pump 27.

A gap 30 is formed between the tubing string 20 and the casing 21. The gap cavity 30 communicates with the annular cavity 31 of the manifold 32. A discharge line 33 is connected to the manifold 32, the other end of which is above or inside the reservoir 24.

The process control system is made in the form of a computer 34 (system unit) to which a monitor 36, a keyboard 37, and a mouse-type manipulator 38 are connected by electrical connections 35.

Computer 34 using a geophysical cable 35 is connected to a source of acoustic vibrations 19, which with a winch 39 is lowered into the tubing string 20.

Device operation

When working (Fig.1 ... 4) include a computer 34, which is pre-installed with the appropriate software.

In addition, the voltage is supplied to the drive 28 of the pump 27 and the flushing fluid is supplied through the supply pipe 29 to the downhole filter 1, then through the gap 30, the cavity 12 to the collector 32 and then returned via the discharge pipe 33 to the tank 24. At the same time, the computer 34 via a geophysical cable 18 supplies an alternating voltage to the acoustic vibration source 19, which creates pressure pulsations in the cavity 12 inside the downhole filter 1. As a result, solid particles from the outside of the downhole filter 1 fall into the gap 30 and then into the reservoir 24.

The computer 34 determines the speed of sound in the washing liquid depending on its temperature, calculates the updated design resonant frequency, which may slightly differ from the resonant frequency of the resonator indicated in its passport.

Software for implementing the method is developed.

Computer requirements: Pentium 4 or later, Windows-XP-7 or 8.

The application of the invention allowed:

- to increase the efficiency of cleaning the downhole filter due to the high power of resonant pulsations,

- accelerate the cleaning of the downhole filter,

- fully automate the cleaning process,

- to ensure ease of use, since almost all equipment is located on the surface,

- to ensure maintainability of the equipment due to its placement above the ground or the ability to quickly rise,

- quickly establish mass production of equipment for cleaning well filters.

To use mass-produced personal computers with virtually no modifications, apart from the development of a management program.

Claims (1)

A downhole filter cleaning device containing an acoustic oscillation source mounted inside the downhole filter using a geophysical cable connected to a computer, characterized in that a resonator is suspended on the geophysical cable near the acoustic oscillation source, and the acoustic oscillation source is configured to change the pulsation frequency for automatic tuning resonant frequency equal to the resonator frequency.

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