RU2299230C2 - Methods of isolation of the productive strata overlapped by the casing strings and the grouting mortar for its exercise - Google Patents

Abstract

FIELD: petroleum industry; natural gas industry; methods of isolation of the productive strata overlapped by the casing strings and the grouting mortar for its realization at the productive strata overhaul repair.

SUBSTANCE: the invention is pertaining to petroleum industry and natural gas industry, in particular, to the productive strata overhaul repair conducted in the process of the fields operation and at elimination of the development wells, which have fulfilled their assignment. The method may find the greatest application at operation of the multi-layer oil-fields and at elimination of the wells of the complex construction, specially on the final stage of the realized works - in the direct proximity to the earth surface for protection, for example, of the potable water, brackish waters and of the permafrost area, where their boreholes are socket by 3-4 and more casing strings. The technical result of the invention is extension of the technological possibilities of the method at the increased efficiency of the isolation of the productive strata. The grouting mortar for isolation of the productive strata overlapped by the casing strings, including Microdur-261R-X and the water, additionally contains calcium chloride, aluminum sulfate, nitriletrimethylenephosphonic acid NTF at the following ratio of the components (in mass %): Microdur-261R-X - 10-30, calcium chloride - 20-50, aluminum sulfate - 0.5-3.0, NTF - 0.0-0.2, water - the rest. The method of isolation of the productive strata overlapped by the casing strings including installation of the isolation cement bridges provides, that one of the isolation cement bridges is installed in the production string by 10-30 m below the interval of works, then using the hydroabrasive perforator cut slits in the casing strings - in the operational string and the intermediate strings - the vertical slits (3-5 slits per one meter), by means of the hydroabrasive cutter below and above the interval of the vertical slots cut all the casing strings forming the horizontal slits and the local cavities, in the formed vertical and horizontal slits and in the local cavities press through the above-mentioned grouting mortar with location of the roofing of the isolation bridge by 10-20 m above the interval of the works, then install the control isolation cement bridge, the base of which is placed on the roofing of the isolation bridge.

EFFECT: the invention ensures extension of the technological possibilities of the method at the increased efficiency of the isolation of the productive strata.

2 cl, 2 dwg, 1 tbl

Description

The invention relates to the oil and gas industry, in particular to overhaul carried out in the process of exploitation of fields and liquidation of wells that have fulfilled their purpose. Will find the greatest application in the exploitation of multi-tiered deposits and in the liquidation of wells of complex design, especially at the final stage of work carried out in close proximity to the earth's surface for protection, for example, of low-mineralized drinking water and permafrost zone, where their trunks are planted with 3-4 or more columns .

A known method of eliminating wells, RF patent No. 2074308 publ. 02/27/97, which consists in installing a cement bridge in the casing over the production horizon of the cement bridge, in which, in the presence of a section of a well of highly ductile rocks in a section of a well, after setting up a cement bridge, an annulus of wells with its column space within the boundaries of the interval of ductile rocks is reported, then an additional cement the bridge so that its roof corresponds to the lower boundary of the interval of highly plastic rocks, after which they ensure the flow of highly plastic rocks into the column space TVO well by setting the last hydrostatic pressure from the condition:

where ρ _cp is the weighted average density of rocks, g / cm ³ ;

N - the depth of the bottom of the interval of highly plastic rocks, m;

σ _T is the conditional yield strength of a highly plastic rock, MPa.

The disadvantages of this method are:

- narrow scope, since this method can only be implemented if there is an interval in the section of the well of highly plastic rocks (salts, clays) lying directly above the productive horizon, and provided that they have such a property as fluidity (creep);

- high material costs associated with the milling of casing strings when creating a technological window and with the duration of the process of flowing of plastic rocks during the formation of a natural natural tire. Depending on the properties of ductile rocks, thermobaric conditions of their occurrence, and the diameter of the trunk, the duration of the process can vary from 17 to 100 days. and more.

Closest to the technical nature of the method according to the invention is a method of isolating an overlapped production casing productive formation according to the patent of the Russian Federation No. 2154150, publ. 08/10/2000, including the installation of cement bridges in the production casing of the well, where one of the cement bridges is installed in the cover of the productive formation of the well, for which the wellbore is previously freed from the installation of the cement bridge from the production casing and cement ring by milling the production casing and drilling a cement ring and the wellbore is expanded by 10-15 mm away from the original size of the wellbore. In this case, when installing the bridge, non-shrinking or corrosion-resistant or expanding materials are used.

The disadvantages of this method are:

- large time and material costs associated with the milling of casing strings when creating a technological window (freeing the barrel from casing strings and cement rings). These costs depend on the number of casing strings, steel grade, height of the process window, depth of the work interval and can take from 7 to 30 days or more. Most of the time is spent on hoisting operations to replace the cutters of the cutting devices, especially at high strength characteristics of the casing strings;

- a narrow scope, since at this stage of the development of technology there are no milling devices that allow simultaneous or phased milling of more than 2 casing strings. This is due to the structural dimensions of the milling (cutting) devices, the diameter of which must be less than the diameter of the inner column;

- a high probability of sticking a working tool with a milling cutting device due to jamming of cutters and a possible collapse of the rock in the interval of the technological window due to the vibration effect on it, accompanying the process of milling the bodies of casing strings;

- low efficiency of isolation of the reservoir, mainly due to the unfiltered coarse-dispersed (dch = 30-100 microns and more) cement slurry into the reservoir and the fragility of the fluid-tightness of the cement-based insulation bridge. It is well known that over time, cement stone ages and collapses, becoming permeable to reservoir fluids (gas, oil, water). This occurs due to chemical transformations inside the cement material and under the influence of external aggressiveness of the environment. The use of expanding materials does not allow creating a high-quality fluid-resistant screen.

Known grouting according to A.S. SU No. 692982, publ. 10.30.79, for the isolation of absorbing formations, containing an aqueous solution of calcium chloride and a polymer additive, in which to obtain a cement slurry having a cured state with high structural strength under conditions of intense water overflows, it contains gypsum-alumina cement as a binder, and as a polymer additives - hydrolyzed polyacrylonitrile (hypane) in the following ratio of components, wt.%:

Gypsum-alumina cement 41-51 Gipan 38-23 Aqueous solution of chloride calcium (density 1.06-1.10 g / cm ³ ) 21-26

This grouting mortar, among others, has the following disadvantages:

- a narrow scope, associated with the low technological quality of this solution, due to the instant coagulation of hypane in contact with an aqueous solution of calcium chloride, often leading to emergency situations due to clogging of pumping units and blockage of pressure pipes with a rubber-like coagulant;

- low efficiency of insulation work, due to the lack of filterability in the reservoir due to its non-fluidity after mixing the components according to the technology of work;

- the fragility of the fluid-resistant screen created from it, since in a short time (1-5 months), after complete coagulation of the hypane, the stone acquires a porous structure and becomes permeable to reservoir fluids.

In contact with drinking, weakly mineralized and produced waters, where the content of polyvalent metal ions (Ca ⁺⁺ , Mg ⁺⁺ , Al ⁺⁺⁺ , Fe ⁺⁺ , etc.) is less than 8-10 g / l, a rapid dissolution of hypane occurs, and accordingly destruction of cement stone.

A well-known grouting solution for isolating absorbing layers, including calcium chloride and water, in which to increase the quality of insulation by increasing the stability of groutstone erosion with washing liquids, it additionally contains a water-soluble metal sulfate in the following ratio of components, wt.%:

Calcium chloride 52,4-61,5 Water soluble metal sulfate 0.2-4.4 Water rest

(SU No. 1559115, publ. 04/23/1990)

Along with a clear advantage over most analogues, such as high penetration (filterability) even in low-permeability formations, it has the following disadvantages:

- a narrow scope, due to the crystallization temperature, which is less than 15-20 ° C, which does not allow its use in wells where formations have a higher temperature, and such an overwhelming majority.

This is due to the fact that above 20 ° C the solution becomes unsaturated, therefore it does not harden (crystallization does not occur) and remains in a liquid state;

- the duration of the formation of the fluid-resistant screen (from 3 to 60 days or more depending on thermobaric conditions) associated with the processes of crystallization and polycrystallization;

- the fragility of the insulating bridge created from it - a fluid-resistant screen due to erosion by formation waters with high dissolving power, since they are undersaturated solutions (brine exclusion).

The closest analogue of the invention is a grouting mortar for isolating a productive formation covered by casing strings, including cement, Microdur 261R-X and water (RU 2223386 C2, publ. 10.02.2004).

The aim of the invention is to expand the technological capabilities of the method while increasing the efficiency of isolation of the reservoir by increasing the fluid tightness of the insulating bridge - fluid-resistant screen.

This goal is achieved due to the fact that the cement slurry for isolating the reservoir, covered by casing strings, including Microdur-261R-X and water, additionally contains calcium chloride, aluminum sulfate, nitrilotrimethylene phosphonic acid (NTP) in the following ratio of components, weight. %: Microdur-261R-X 10-30, calcium chloride 20-50, aluminum sulfate 0.5-3.0, NTF 0.0-0.2, the rest is water. In the method of isolating a productive formation covered by casing strings, including the installation of insulating cement bridges, one of the insulating cement bridges is installed in the production string 10-30 m below the interval of work, then a perforator is cut in the casing - production and intermediate vertical slots of 3 -5 slots per meter, using a waterjet cutter below and above the interval of vertical slits, cut all casing strings, forming horizontal slots and local cavities, formed by vertical and horizontal slit local cavity is forced from said backfill arrangement solution roofing insulation bridge 10-20 m above the operating range, then set the control insulating cement plug, which has a sole on the roofing insulating bridge

The essence of the invention lies in the fact that to isolate the reservoir, covered by several casing strings, it is not necessary to free the wellbore in the interval of installing bridge reinforcement from the operation of the casing and cement ring, and it is also not used when installing bridges, non-shrink or expanding materials, since the first case will require large material costs associated with the milling of casing strings when creating a technological window (freeing the wellbore from casing bosom and cement rings), narrow scope, since can conduct simultaneous or phased milling in more than 2 casing strings, and the use of cement, which, under the influence of an external aggressive environment, ages and breaks down, and does not allow expanding materials to create a high-quality fluid-resistant screen.

In the present invention, one of the cement bridges is installed below the interval of work.

The location of the roof of one of the cement bridges below the work interval is necessary for the formation of a technological sump that provides geophysical surveys (GIS), technological tripping and prevents the possibility of picking up the tool with sand during hydro sandblasting and dissecting columns. In addition, the presence of the above cement slurry in the wellbore below the dissection plane increases the reliability of the installed insulating bridge - fluid-resistant screen. The location of the roof of the cement bridge 9 below the interval of less than 10 m is impractical and low-tech, since the size of the drill pipe is 8-10 m and the reliability of the work will decrease.

The location of the roof of the insulating bridge - the fluid-resistant screen from the highly penetrating above-mentioned grouting mortar in the production casing 10-20 m above the work interval increases the insulating reliability and prevents its possible vertical movement due to adhesion when isolating the reservoirs with high pressure flow. The location of its roof higher than 20 m is impractical due to the cost overrun of the expensive "Mikrodur".

The opening area when creating 3-5 slots per meter with sandblasting is equivalent to the area with 25-40 holes per meter obtained by the well-known cumulative perforators, which is consistent with existing technologies for selling cement slurries.

The formation of vertical slots in the interval (opposite) of the occurrence of fluid-resistant rocks in all casing strings is necessary to ensure free communication of the casing with annular spaces and the space between the outer strings and the rock. Cutting into parts of all casing strings by cutting them with a waterjet cutter in horizontal planes below and above the interval of previously created vertical slots is necessary, firstly, to ensure free penetration (more complete filling) of the cement slurry in all directions in the interval of creation of the insulating bridge - fluid resistant screen. At the same time, the weight load (stress) on the remaining upper part of the well structure will decrease, which will extend the period of its protective action in conditions of external aggressiveness of the environment. Secondly, the dissection of casing strings and cement rings in annular and annular spaces allows to completely overlap (isolate) possible previously existing migration routes of formation fluids (microcracks, cavities, etc.) in annular and annular spaces. At the same time, in the dissection planes, the possibility of the occurrence of fluid migration over time at the metal – cement plug contact, which is inevitable due to aging and destruction of the casing string body, is excluded.

The local cylindrical cavities are washed out in the fluid-resistant rock during the cutting of the casing, after they are cut, to increase the contact area of the cement slurry with the rock, including on the lower and upper end surfaces of the installed insulating bridge - a fluid-resistant screen.

Squeezing the prepared molecularly dispersed fluid with a high penetrating ability into the prepared interval allows filling always available voids that are associated with existing well fixing technologies in annular spaces, the space between the outer string and rock, as well as specially blurred local cylindrical cavities. Selling is carried out under pressure, taking into account the residual strength of the inner casing (production) string, but not more than 0.8 of the fracture value of fluid-resistant rocks, in the interval of which work is performed.

The use of the above cement slurry with high penetration provides the impermeability and durability of the resulting cement stone, while it is stable in acidic and alkaline environments.

When installing a cement bridge on a production casing 10-30 m below the interval of work and a control cement bridge, grouting mortar on Portland cement is used.

The method is as follows.

Figure 1 - condition of the well section before work.

Figure 2 - state of the well after the work.

Well 1 (Fig. 1), equipped with several casing strings, the construction of which according to construction technology includes production casing 2, intermediate strings 3 and 4, and conductor 5, which opened the upper reservoirs 6, fluid-resistant deposits (clays, mudstones, salts, gypsum, anhydrites and etc.) 7 and productive (gas-oil and water-saturated) reservoir 8 - a possible source of inter-reservoir flows (MPP) and intercolumn pressures (MKD) - are suppressed by well-known methods. Then, if the reservoir is opened (has communication with the column space) - it is isolated by well-known methods and a cement bridge 9 is installed in the production casing, the roof of which is 10-30 meters below the interval of the proposed work, and pressure pipes 10 (tubing, BT) are lifted surface.

A waterjet perforator of a known design is attached to the pressure pipes 10 on the surface, lowered into a well and, in the interval of work with a waterjet, produce 2, 3, 4 vertical slots 11 in the casing 10 to 25 mm wide and up to 100 mm or more in height, 3- 5 slots per meter (figure 2). After hydroabrasive perforation, the perforator is raised to the surface, and instead of it, a hydroabrasive cutter of known design is attached to the pressure column 10. Then, the waterjet cutter is installed opposite the planned lower mark of the cut and the casing strings 2, 3, 4 are cut into pieces by cutting them in a horizontal plane with an abrasive jet with a thickness (height) of the cut of at least 10-30 mm below the lower vertical slots 11 previously created by the waterjet punch, forming horizontal slots 12.

After that, the waterjet cutter is raised higher and installed at the upper mark of the cut, where the casing strings 2, 3, 4, 5 are also cut into pieces in a horizontal plane located above the upper vertical slots created previously by the waterjet perforator in the work interval, forming horizontal cracks 13. In the process of cutting the casing strings due to the destructive action of the waterjet in the rock 7, local cylindrical (wheel-shaped) cavities 14 are formed.

At the end of the cut, the waterjet cutter is raised to the surface. The pressure column 10 is lowered to the lower part of the work interval and the well is thoroughly washed from the abrasive (sand) debris of cement and rock sludge.

In a known manner, the estimated volume of molecularly dispersed cement slurry 15 is delivered to the work interval, which is then pressed through the vertical slots 11 and horizontal slots 12, 13 formed during the work into the annular spaces (between the casing strings 2, 3, 4, 5), the annular space (between the casing 4, 5 and the mountain fluid-resistant rock 7) and blurred local cylindrical cavities 14. After the hardening of the cement slurry 15, forming a fluid-tight insulation bridge (fluid-resistant screen), the roof of which is 10-20 m higher than the interval of work, then a control cement bridge 16 is installed, the sole of which is located on the roof of a fluidproof insulation bridge with a capacity of at least 50 m according to RD 08-492-02 (Instructions on the procedure for liquidation, conservation of wells and their equipment estuaries and trunks).

As a result of the work carried out as described above, in an short time (1-7 days), an effective and reliable insulating bridge is created - a fluid-resistant screen made of a (monolithic) stone of a mobile molecularly dispersed solution having a high penetrating power, reinforced with perforated pieces of casing strings of a given length. At the same time, the number of casing strings existing in well designs known worldwide in the world (usually from 2 to 5) practically does not affect the success and duration of work, unlike the prototype.

The interval of work and the height of the insulating bridge being created - a fluid-resistant screen for each particular case are selected taking into account the geological section of the compounded rocks, the well design and the results of drilling, field geophysical research of wells (GIS), as well as testing of productive horizons.

It is known that the transition from a stable state of a saturated solution to a metastable (unstable) can be accomplished by cooling or evaporation, as well as by introducing an additional amount of the dissolved compound into it. Therefore, the introduction, in contrast to the prototype of the additive, hardener allows you to expand the temperature range of its application to 100 ° C or more. This is also due to the fact that during the hydration of the hardener, the concentration of salts (CaCl and Al ₂ (SO) ₃ ) in the solution sharply increases due to the binding of part of the water component to the dehydrated additive, and this leads to crystallization and solidification of the solution even at very high temperatures, up to 100 ° C and higher.

As a part of the grouting mortar, a finely dispersed binder of the Microdur-261K-X type is used.

The specified Microdur is a particularly finely dispersed mineral binder with a guaranteed smooth measurement of particle size distribution. "Microdur" is produced by air separation of dust by grinding cement clinker. The manufacturing technology of OTDV "Mikrodur" was developed and mastered by the specialists of the company "INTRA-BAVGmbH" together with the specialists of the concern "Dyckerhoff" (Wiesbaden, Germany) and is protected by the European patent.

The diameter of the Mikrodur grains is 6-10 times smaller than the particles of the cement clinker itself.

Due to the small size (grain diameter <6-10 μm) of the particles and the smoothly selected particle size distribution, the Mikrodur suspension has a fluidity comparable to that of water, even with a minimum W / C. The expiration time (conditional viscosity) of a suspension under the age of 3 hours ranges from 28 to 30 seconds and provides high penetration into loess soils, dense concrete and rock. Mikrodur is a powder with a specially selected mineral and particle size distribution. This provides a high water holding capacity (W / C up to 6.0) and rheological characteristics commensurate with the rheology of ordinary water.

Mikrodur-261K-X is resistant to chemical influences, including the effects of sulfates, hydrogen sulfide and chlorine. Thus, it can be considered as an alternative to liquid glass and polymer compositions (epoxy, carbide, phenol formaldehyde, etc.) with the following advantages: durability, simple and convenient technology for preparing a suspension and injection, environmental cleanliness, uniformity with conventional cements in composition, compatibility with cement, concrete and reinforced concrete, the ability to perform work in conditions of flooded and water-saturated structures and formations.

The choice of calcium chloride (CaCl ₂ ) as an astringent is due to the fact that it has the highest solubility of the available inexpensive and widely used salts, thereby providing a greater yield of solid material from the molecular solution during crystallization. In addition, it forms with the clinker "Mikrodura" insoluble complex hydrated salts, which ensures the long life of the cement stone.

Aluminum sulfate, unlike sulfates of magnesium, sodium, and others, is non-aggressive to hydrated neoplasms of Mikrodur. The inclusion of aluminum sulfate (Al ₂ (SO ₄ ) ₃ ) in the grouting mortar makes it possible to increase the resistance of the salt part to erosion (dissolution) by produced water, accelerate the hardening of the Mikrodur component, and increase its strength, impermeability and, accordingly, the durability of the stone.

When the content of aluminum sulfate is more than 3.0%, cement stone does not form for a long time and a large water sludge is observed. An additive of less than 0.5% reduces the strength of the cement.

Additive, if necessary, NTF in the cement slurry allows you to provide the viscosity necessary for the technology of work and the timing of its setting. An NTF content of more than 0.2% will dramatically increase the setting time to 20-25 hours or more, which is not technologically necessary.

When the content of calcium chloride is less than 20% and the hardener is less than 10%, a large water sludge of up to 50% is observed, which does not allow to obtain cement slurry in full due to the undersaturation of the molecularly dispersed cement slurry, especially at high temperatures. The introduction of more than 50% calcium chloride and more than 30% hardener into the grouting mortar makes it non-pumpable and unsuitable for technological work, especially in the field of low temperatures.

The results of laboratory work are shown in the table.

Grouting mortars according to the invention, prepared according to the recommended ratios of the components, have a fluidity close to the fluidity of water. The nominal viscosity of the VP-5 device until the time of thickening ranges from 19-30 s at a temperature of 20 ° C (for water 15-16 s.). This ensures their manufacturability and promotes the deep penetration of cement slurry even in low permeable rocks. In this case, there is no sludge and crystallization (formation) of stone occurs in full volume of the initial mixture. The content of active calcium oxide (CaO) in Mikrodur is 1.4-1.5 times less than in the clinker of used Portland cement. This and the blocking of its particles by salts of calcium chloride and aluminum sulfate ensures the impermeability and durability of the resulting cement stone, while it is stable in acidic and alkaline environments.

Using the proposed method provides the following advantages:

- reduced in comparison with the prototype time and material costs for the installation of an insulating bridge - fluid-resistant screen in 2-5 times or more. This is mainly due to the fact that there is no need for multiple tripping operations to replace the cutters of milling cutting devices;

- the scope of application is expanding, since the use of waterjet perforation and a waterjet cutter allows you to open and cut up to 4-5 casing strings at the same time with minimal cost (that is, receive message from the column space with its casing and rock);

- the probability of emergency tool tacking (pressure column with its bottomhole layout) is minimized, since work is carried out in a barrel equipped with casing strings;

- increases the efficiency of isolation of the reservoir by creating a reliable and durable fluid-resistant screen. This is due to the use of a molecular disperse system as a grouting mortar, which has great penetration even in low-permeability rocks, whose stone is stable in acidic and alkaline environments.

The economic effect of using the proposed method depending on the design of the well, depth, power of the interval of work and the number of installed insulation bridges - fluid-resistant screens will be from 0.3 to 3.0 million rubles or more.

Table No. p / p Component composition, wt.% The temperature of the experiment, ° C Note Calcium chloride Aluminum sulphate Microdur -261R-X NTF (retarder) Water one 18.0 0.4 9.5 0 72.1 24 Sludge, 25% 2 12.98 0.34 21.8 0 64.88 97 The stone is formed, but water-sludge 24.6% 3 25.45 0.33 10.61 0 63.61 24 Sludge 54.7% four 25.45 0.33 10.61 0 63.61 97 Stone does not form 5 21.25 0.4 25.63 0 52.72 24 There is no sludge, the beginning of setting 3-4 hours after mixing. The stone is not strong enough, less than 3.0 MPa 6 21.25 0.4 25.63 0 52.72 97 7 24.75 0.99 24.75 0.18 49.33 24 The beginning of setting 19-20 hours, the stone in full, strength more than 7.0 MPa 8 24.75 0.99 24.75 0.18 49.33 97 9 24.75 0.99 24.75 0.25 49.26 24 The solution did not set in 48 hours 10 24.75 0.99 24.75 0.25 49.26 97 The solution did not set in 48 hours eleven 39.47 1.3 19.74 0,07 38.79 24 Setting time is 16-18 hours. Stone strength 8.5 MPa after 3 days 12 39.47 1.3 19.74 0,07 38.79 97

13 45.45 3.3 15.15 0 35.75 24 The stone was formed within 7 days. On day 14, the stone increased in volume by 1.5% fourteen 45.45 3.3 15.15 0 35.75 97 fifteen 44.12 5.88 14.71 0 35.29 24 The solution is not pumped, the stone does not form after 10 days. Sludge more than 50% 16 44.12 5.88 14.71 0 35.29 97 17 52,4 1,03 25.06 0.15 21.36 24 The solution is not pumpable eighteen 44.5 0.9 34.7 0.25 19.65 24 The solution is not pumpable 19 32,45 1.18 22.12 0 44.25 24 The setting begins after 3.5 hours, the strength of the stone after 5 days is 11 MPa. Setting starts after 5 days twenty 32,45 1.18 22.12 0 44.25 24 21 29.9 2.1 30,0 0 38,0 24 Start of setting after 3-4 hours, no water discharge 22 29.9 2.1 30,0 0 38,0 97 23 29.9 2.1 30,0 0.1 37.9 24 Setting start after 13-14 hours 24 29.9 2.1 30,0 0.1 37.9 97

Claims (2)

1. Grouting mortar for isolating a productive formation covered by casing strings, including Mikrodur-261R-X and water, characterized in that it additionally contains calcium chloride, aluminum sulfate, nitrilotrimethylene phosphonic acid - NTP in the following ratio of components, wt.%: Microdur-261R-X 10-30 Calcium chloride 20-50 Aluminum sulphate 0.5-3.0 NTF 0,0-0,2 Water Rest 2. A method of isolating a productive formation covered by casing strings, including the installation of insulating cement bridges, characterized in that one of the insulating cement bridges is installed in the production string 10-30 m below the work interval, then a waterjet perforator is cut in the casing strings - production and intermediate vertical slots of 3-5 slots per meter, using a waterjet cutter below and above the interval of vertical slits cut all casing strings, forming horizontal slots and locks nye cavity formed in the vertical, horizontal slit and the cavity is forced local plugging fluid of claim 1, with an arrangement of roofing insulation bridge 10-20 m above the operating range, then set the control insulating cement bridge, which is positioned on the sole of roof insulating bridge.

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