Method to isolate water influx in well

FIELD: oil production, particularly preventing gas- or water-coning phenomena, for instance the formation of a conical column of gas or water around wells.

SUBSTANCE: method involves injecting hydrophobic composition in water influx channels; lowering and installing shutter provided with shoe at shutter end within water influx interval. The shoe may slide upwards in axial direction and is retained with shear members. The shoe has longitudinal and side communicating channels. Before hydrophobic composition injection the shutter is lowered to well bottom without supporting thereof. After that low-diameter pipe string is additionally inserted in shutter to provide airtight cooperation thereof with longitudinal channel. After hydrophobic composition injection through side channels the shutter is lowered to well bottom up to upward shoe movement with side channel closing. Low-diameter pipe string is removed from well before shutter installation.

EFFECT: improved water influx isolation.

1 dwg

 

The invention relates to the oil industry, in particular to methods of restriction and isolation of the water.

There is a method carried out by a Device for overlapping zones complications in the well" (A.S. No. 1712581, EV 29/10, 33/13, publ. bull. No. 6 from 15.02.1992, including the descent and installation interval zone complication profile peregrinates.

The disadvantage of this method is the ability to isolate water production breakthrough of water along the walls of peregrinates especially when drilling along naplastovanija rocks.

The closest in technical essence and the achieved result is "a Way to isolate water production in oil wells" (patent RU №2114990, EV 43/32, 33/13, publ. bull. No. 19 of 10.07.1998, including the descent and installation interval inflow of peregrinates while before installing peregrinates in the channels of water pumped hydrophobic water-insoluble composition viscosity 200-1700 MPa·s speed shift 2 - 145-1and after injection of the composition of its stand in the channels of water under pressure for structural hardening composition.

The disadvantage of this method is the large period of time between the injection of the composition into the channels of water production and installation of peregrinates well spent on the descent of peregrinates that can lead to squeezing value is positive quantity of composition back in the trunk, especially at high formation pressure water shut-off.

The technical task of the invention is to improve the insulation quality of the water in the well due to a significant reduction in the time between the injection of hydrophobic composition in the channels of water production and installation of peregrinates.

The technical problem is solved by means of isolating the water in the well, comprising pumping into the channels of water in the hydrophobic composition, descent and installation interval inflow of peregrinates with a Shoe on the end.

What's new is that before download hydrophobic composition make the descent without relying on the borehole bottom of peregrinates, the Shoe which is installed with the possibility of axial movement upwards, fixed shear elements and equipped with longitudinal and lateral connecting channels, after which the interior of peregrinates additionally descend to download the hydrophobic part of the string of pipe of small diameter to a tight interaction with a longitudinal channel, after the injection through the side channels hydrophobic composition pericryptal lower on the bottom to move up Shoe with overlapping side channels, and to install peregrinates column of small diameter pipes removed from the well.

The drawing shows pericryptal with a column of small diameter pipes inside.

The method of isolation of the water in the borehole (not shown) carry out trace is accordingly.

In the well put no emphasis on the bottom (not shown) pericryptal 1 on the string of pipe 2, connected through sub 3 left-handed 4 to perekryvatel 1, which at one end is equipped with a Shoe 5 with 6 longitudinal and lateral 7 channels. Moreover, the Shoe 5 is installed in pericryptal 1 with the possibility of axial movement up with tight overlapping of the side channels 7 and the fixed cutting elements 8. Then inside of peregrinates 1 additionally lower a column of small diameter pipes 9 (for example, a column of continuous pipe) to sealed engagement with the longitudinal channel 6. The column of small diameter pipes 9 are injected hydrophobic part 6 through the longitudinal and lateral 7 channels in the channels of water. After exposure technologically necessary time sufficient for structural seal, pericryptal 1 is lowered to the slaughter, cutting elements 8 are destroyed and the Shoe 5 is pericryptal 1, overlapping the side channels 7. Next, the column of small diameter pipes 9 extracted from the well, the string of pipe 2 create excessive pressure sufficient to blow-UPS of peregrinates 1 to tight interaction with the borehole wall. Then the string of pipe 2 gives the rotation, as a result, the left thread 4 sub 3 turns away from peregrinates 1. Then the string of pipe 2 is extracted from wells. When necessary the STI for better and tightly pressed to the walls of the well pericryptal 1 increase (for example, razvalivatelyam or mandrel). The process is completed. If there is a need for further deepening of wells, the Shoe 5 is made from legkousvojaemogo material (e.g. iron).

The proposed method is isolation of the water in the well can improve the quality of insulation of the water in the well due to a significant reduction in the time between the injection of hydrophobic composition in the channels of water production and installation of peregrinates.

The way to isolate water production in a well, comprising pumping into the channels of water in the hydrophobic composition, descent and installation interval inflow of peregrinates with a Shoe on the end, characterized in that before the injection of hydrophobic composition make the descent without relying on the slaughter of peregrinates, the Shoe which is installed with the possibility of axial movement upwards, fixed shear elements and equipped with longitudinal and lateral connecting channels, after which the interior of peregrinates additionally descend to download the hydrophobic part of the string of pipe of small diameter to a tight interaction with a longitudinal channel, after the injection through the side channels hydrophobic composition pericryptal lower on the bottom to move up Shoe with overlapping side channels, and to install peregrinates column of small diameter pipes removed and the wells.



 

Same patents:

FIELD: oil and gas industry, particularly temporary plugging of productive reservoir intervals, killing of wells having abnormally low reservoir pressure during well repair and to separate gas and oil intervals during plugging of multizone reservoir under combined development thereof and lost-circulation zone isolation during well drilling.

SUBSTANCE: method involves creating porous packer by injection of two compositions, namely polymeric solution and plugging liquid in well, wherein polymeric composition includes water-soluble polymer, cross-linking agent, foaming agent and water. The water-soluble polymer is polyacrylamide and/or carboxymethylcellulose and/or styromaleate. Above components are taken in the following amounts (% by weight): water-soluble polymer - 0.1-10, cross-linking agent, namely Cr2(SO4)3, Cr(C2H3O2)3, CrCl3, - 0.05-10, foaming agent, namely sodium alkyl benzene sulfonate, Neonol, sulfanole, Neftenol, - 0.1-5.0, remainder is water. The composition may additionally have gaseous agent, namely nitrogen, carbon dioxide, natural gas so that expansion ratio of the composition is 1.28-3.0. The plugging liquid is invert emulsion based on hydrocarbon phase, namely oil and/or hydrocarbon solvent, aqueous phase, namely water and/or salt solution of CaCl2 or NaCl2 or MgCl2 or BaCl2 in emulsifier presence. Above components are taken in the following amounts (% by weight) - hydrocarbon phase 15-18, aqueous phase - 72-82, emulsifier is 3-10. The composition is serially injected in well and followed by well killing liquid injection. Extreme dynamic shearing stress of polymeric solution is 25-110 Pa. Static shearing stress of porous packer is 50-410 Pa. Composition is formed on surface with cementing agent usage. The compositions are injected in laminar flow regime. Packer porosity is 10-50%. Plugging liquid volume is 2-4 m3, density thereof exceeds that of well killing liquid. The injection is carried out in two stages and time interval between the stages is not less than 30 min. Injection pressure is not higher than proof-test pressure. In winter unfreezing liquid is added to polymeric composition. Packer density is changed by heaving agent, namely metal salt CaCl2, KCl, MgCl2, BaCl2 solution addition. Packer is also used to create elastico-viscous screen to protect against mechanical impurities entering from exploitable reservoir or to isolate reservoirs during simultaneous or serial reservoir exploitation. Packer is retained for predetermined time interval.

EFFECT: possibility to maintain collecting properties of reservoir during current well repair and well workover.

20 cl, 5 ex, 3 tbl

FIELD: oil and gas production industry, particularly to treat bottomhole formation zone during oil and gas production.

SUBSTANCE: method involves inserting material for further exothermal reaction performing in well; forcing hydrochloric acid through the material and executing time delay. The material used for exothermal reaction performing is in the form of aluminum cuttings. First of all aqueous carboxymethylcellulose solution is formed. Then calculated amount of aluminum cuttings and grinded raw rubber are added to the solution. Above components are taken in the following amounts (% by weight): carboxymethylcellulose - 1.5, aluminum cuttings - 14.5, raw rubber - 11.6, water - 72.4. After that the ready solution is forced in reservoir and 20% hydrochloric acid is injected in well. Ratio between aluminum and hydrochloric acid is 25.0 parts by weight of aluminum per 75.0 parts by weight of hydrochloric acid.

EFFECT: increased bottomhole formation zone treatment reliability.

1 tbl

FIELD: oil and gas production.

SUBSTANCE: whole process comprises primarily exposing well on polymer-chalk mortar, perforating bottom zone of formation under polymer-chalk mortar layer, creating acid-degradable protective shield in bottom zone by forcing polymer-chalk mortar under pressure exceeding specified cementation pressure by 10-15%. Thereafter, casing string is descended, annular space is cemented, and bottom zone of formation is re-perforated through casing string and protective layer is destroyed with acid. Polymer-chalk mortar has following composition, wt %: soda ash 1-6, carboxymethylcellulose 1-6, polyacrylamide 2-3, clay 48-52, chalk 46-50, water - the balance.

EFFECT: increased productivity of formation due to prevented negative action of drilling fluids and appearance of softened bottom zone.

FIELD: oil production industry, particularly methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells.

SUBSTANCE: method involves lowering casing pipe string in well, wherein the casing pipe string is provided with channels located in water-bearing productive reservoir section; cementing hole annuity; isolating water-bearing section of productive reservoir by injecting water-proofing composition via casing pipe string channels; closing the channels with gate and exposing oil-bearing productive reservoir section for the second time. Before casing pipe string lowering in well hollow rigid centrators are formed in the channels. The centrators and the channels are filled with bitumen and closed with gate. Before water-proofing composition injection in water-bearing productive reservoir section the gate is opened. The water-proofing composition is non-hardening water-proofing composition. Then hollow rigid centrators and channels are freed of bitumen and cement stone is broken within the interval of water-bearing productive reservoir section by implosion action application thereto.

EFFECT: increased efficiency and decreased labor inputs.

2 cl, 1 dwg

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 isolationof 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 isolationof the productive strata.

2 cl, 2 dwg, 1 tbl

FIELD: oil extractive industry, in particular, methods for extracting oil deposit with gas cap, preferably at beginning stage of extraction of oil deposit.

SUBSTANCE: method includes drilling directional force wells, product and gas wells, forcing water into oil bed through force wells, extracting oil through extractive wells and forcing incidental oil gas into gas cap through gas wells. In accordance to invention, in case of vertical penetrability of oil bed constituting 0,5-0,8 of its horizontal penetrability, at beginning development stage at least one more product well is drilled with at least one horizontal borehole. In directional product wells lower part of gas cap of bottomhole zone in contact with oil bed is isolated for thickness and depth not less than falling radius of bed pressure in bottomhole formation zone during oil extraction. That is a radius of bottomhole formation zone, in which depression on bed is at least 50% lower than difference of bed and bottomhole pressures in well. Isolation is performed first of all in wells with maximal depression on bottomhole formation zone. Through force wells fed in turns into oil bed are sub-product or senoman water and incidental oil gas.

EFFECT: decreased danger of entry of incidental oil gas from gas cap into extracting wells.

2 dwg

FIELD: oil industry, particularly to prevent gas- or water-coning phenomena, for instance the formation of a conical column of gas or water around wells.

SUBSTANCE: method involves injecting acetone, to which separol in amount of 0.2% is added, in pool and then injecting silicone compositions in the pool.

EFFECT: increased product output due to improved well waterproofing.

1 tbl

FIELD: treatment of well drilled in productive reservoir, which is at later operation stage.

SUBSTANCE: method involves injecting polymeric compositions in reservoir; lowering hydroacoustic generator in well; applying hydroacoustic waves to polymeric compositions and to flushed reservoir interval; preparing inflow stimulation and stimulating well inflow. Polymeric compositions or solid dispersed filler in hydrocarbon liquid are injected in productive formation. Hydroacoustic generator is connected to flow string to be lowered in perforation zone. Polymeric composition or dispersed filler mixed with hydrocarbon liquid treatment is carried out when above materials are delivered to perforation interval and during injection thereof in reservoir. Before inflow stimulation hydroacoustic generator is installed in productive non-worked out reservoir interval and the interval is cleaned by applying hydroacoustic action to it. To apply above hydroacoustic action spectrum of acoustic wave with 0.2-16 kHz frequency and 1.5-6.0 MPa amplitude is generated. Then one spectrum frequency resonance is provided, wherein frequency is equal to that of self-oscillation of particles, which clog productive reservoir cracks and pores during primary opening thereof. Pressure drawdown is simultaneously created in well. Inflow stimulation and well development is carried out with the use of downhole vortex pump.

EFFECT: increased production well output along with water influx restriction, improved isolation quality and reduced repair costs.

FIELD: oil production, particularly to isolate casing annulus and tubing-casing annulus with the use of plugging polymer-based compositions curable in reservoir conditions.

SUBSTANCE: method involves injecting isolation material in injection or production well, wherein the isolation material includes polymer curable in reservoir conditions; forcing thereof through well and holding the composition inside well for time enough to cure and strength development. The composition is water-soluble polymeric composition including acetone-formaldehyde resin in amount of 80.0% by weight, sodium carbonate or potassium carbonate in amount of 4.0-7.0% by weight, chemical reagent Okzil-SM in amount of 0.5 % by weight, remainder is water or 30% NaCl solution. If reservoir temperature is 50°C or less alkali, namely sodium hydroxide NaOH, in amount of 0.1-2.5% by weight is additionally mixed with above composition. In the case of plugging operation performing in high-pressure wells fine inert filler, namely industrial talc, is added in amount of 30-100% of composition volume to be injected.

EFFECT: possibility of casing annulus and tubing-casing annulus plugging in temperature range of 20-90°C.

3 cl, 3 tbl, 3 dwg

FIELD: oil industry, particularly preventing gas- or water-coning phenomena, for instance the formation of a conical column of gas or water around wells.

SUBSTANCE: method involves supplying gel-forming material in isolation zone in one step up to full isolation zone saturation; injecting 27% hydrochloric acid at rate of 2-6 l/sec. The gel-forming material is pulp of syenite alkali-aluminum concentrate in calcium chloride solution having specific weight of not more than 1.2 g/cm3 and taken with volumetric ratio of 1:1. The gel-forming material is supplied at rate of not less than 3 l/sec. The gel-forming material and hydrochloric acid mass ratio is 1:1.

EFFECT: increased technological effectiveness and improved efficiency due to full isolation zone saturation with gel-forming material.

2 ex

FIELD: oil and gas production industry, particularly methods or devices for cementing, for plugging holes, crevices, or the like.

SUBSTANCE: device comprises production tubing lowered in well and pipe string arranged inside production tubing. Production tubing is includes bush having central channel located in lower production tubing part. Pipe string is connected with nipple through sub having seal in top part thereof. Upper and lower radial channels are created in low pipe string part and in upper sub part under sub seal correspondingly. Outer thrust is located over lower radial channels of the sub. The sub may cooperate with central bush channel in air-tight manner.

EFFECT: simplified technology for waterproofing composition preparation and increased waterproofing work quality.

1 dwg

FIELD: oil and gas production industry, particularly methods or devices for cementing, for plugging holes, crevices, or the like.

SUBSTANCE: device comprises production pipe string with pipe string arranged inside it. Production pipe string is provided with liner. Pipe string has cup located at end thereof. The cup has outer thrust. Radial channels are formed in low pipe string part. Disc valve with seat is installed between production pipe string and liner. Seat has rupturable member, which retains the disc valve in opened position. Cup may seal disc valve seat and cooperate with rupturable member.

EFFECT: simplified technology of waterproofing composition preparation and increased waterproofing operation efficiency.

2 dwg

FIELD: oil production, particularly well repair.

SUBSTANCE: device is made as packer assembly including bottom-hole packer adapted to close well annulus due to packer diameter increase under axial compression thereof and pipe arranged in bottom-hole packer cavity. During bottom-hole packer compression the packer slides along the pipe in vertical direction. Device comprises two packer assemblies. Pipe of bottom-hole packer included in upper packer assembly has bottom with orifices and thrust for bottom-hole packer supporting. Device also has outer pipe arranged below lower bottom-hole packer and coaxial thereto. Outer pipe has inner diameter and surface finish to provide sliding thereof along outer surface of pipe located inside bottom-hole packer. Outer pipe has bottom-hole packer thrusts arranged at ends thereof. Lower packer assembly is identical to upper one and is upside down. Lower packer assembly is below upper one and is coaxial thereto. Lower and upper packer assemblies define common outer pipe. Tubing string passes through both packing assemblies through central bottom orifices thereof. Remainder bottom orifices communicate well annulus and clearance between tubing string and outer pipe. Tubing string couplings located over upper packer assembly and below lower one limit vertical bottom displacement.

EFFECT: decreased time and improved well flushing.

2 dwg

FIELD: oil production industry, particularly methods or devices for cementing, for plugging holes, crevices, or the like.

SUBSTANCE: device comprises pipe string lowered in well and provided with shoe at end thereof. The shoe is made as hollow bush and provided with liner formed in end part thereof and with self-sealing collar located from outside thereof. The liner has through orifices. The collar provides flow in bottom-top direction. Pipe string has partition located in lower pipe string part. Upper and lower radial channels are correspondingly formed over and below partition. The liner may cooperate with well bottom. Hollow bush may perform limited movement in upward direction with respect to pipe string and seal lower radial channels.

EFFECT: elimination of cement surge tank usage for waterproofing composition preparation and increased waterproofing works quality.

1 dwg

FIELD: oil and gas production industry, particularly methods or devices for cementing, for plugging holes, crevices, or the like, for instance abandonment of well drilled in permafrost zones.

SUBSTANCE: method involves killing well; removing production tubing; arranging cement bridge over production reservoir and in conductor shoe; filling well bore with non-freezing liquid within permafrost rock interval; dismantling production tree and landing head at well head; installing concrete column on well head; additionally arranging cement bridge in production string below leaking interval; leaving processing mix between additional cement bridge and cement bridge arranged over production reservoir; creating additional perforation orifices within production string leaking interval; injecting and forcing light-weight sealing composition in casing annulus, wherein forcing pressure is 0.7-0.8 of pressure created during production string and cement bridge arranged below leaking interval proof-testing; hardening the light-weight sealing composition; filling said additional perforation orifices with expanding cement mix; arranging cement bridge in conductor shoe after production string leakage elimination; filling well with non-freezing liquid within permafrost rock interval. The light-weight sealing composition includes Portland cement in amount of 15.0-16.0% by weight, epoxy polyurethane polymer in amount of 45.0-47.0% by weight, silica-alumina microspheres in amount of 1.2-2.7% by weight, filler - polyvinylchloride in amount of 18.0-18.5% by weight, latex in amount of 13.5-13.8% by weight, trimethylchlorosiloxane in amount of 0.1% by weight and hardener in amount of 5.4-5.5% by weight. Expanding Portland cement mix comprises plugging Portland cement in amount of 85-90% by weight, silica-alumina hollow microspheres in amount of 10-15% by weigh, hydrocarboaluminate additive in amount of 2-4% by weight, gypsum in amount of 2-4% by weight, plasticizer in amount of 0.2% by weight, remainder is water or 4% calcium chloride solution.

EFFECT: increased efficiency.

1 dwg

FIELD: oil and gas production industry, particularly methods or devices for cementing, for plugging holes, crevices, or the like.

SUBSTANCE: device comprises pipe string with shoe. The shoe is made as hollow bush with conical lower surface, which may perform limited sliding upwards with respect to pipe string. Hollow bush is provided with self-sealing collar arranged from outer side thereof and with shank having technological groove on outer side thereof and with anchoring unit. The anchoring unit is made as cup, which may slide in axial direction with respect to the shank and provided with centrators. The centrators have friction members and pins cooperating with technological groove. Centrators are spring-loaded outwards. The friction blocks are spring-loaded inwards and provided with guiding means arranged inside friction blocks and inclined towards pipe string axis. The guiding means in their working position may cooperate with conical surface of hollow bush. Lower part of pipe string is provided with bridge. Upper and lower radial channels are arranged below and under the bridge. Lower channels may be closed with hollow bush as it slides upwards.

EFFECT: increased efficiency.

2 dwg

FIELD: oil production, particularly methods or devices for cementing, for plugging holes, crevices, or the like.

SUBSTANCE: method involves simultaneously installing two packing mechanisms connected with each other through pipe; flushing well so that counter-current flushing flows passing through tubing string and annular space are directed through isolated channels made in packing mechanisms and in packing mechanism connection pipe, wherein the first isolated channel connects inner tubing string areas located upstream and downstream of packing mechanisms and the second one communicates inner annular space areas upstream and downstream of packing mechanisms. Device comprises packing mechanism including bottom-hole packer, which seals tube space due to packer diameter increase as a result of axial compression thereof, the first pipe located inside bottom-hole packer and tube with radial orifices. Bottom-hole packer end is fastened to the first pipe so that packer may be displaced in vertical direction by to packer deformation. Device comprises two packing mechanisms. Upper mechanism includes inner pipe inserted in outer pipe and having sealing means to provide air-tight sliding thereof inside tubing string. Sealing means have diameters exceeding that of inner pipe. Pipe with radial orifices has upper end threadedly connected with tubing string and is provided with inner bead. Inner bead diameter is less than that of sealing means made in inner pipe. Lower end of pipe with radial orifices abuts against upper bottom-hole packer end. Bottom-hole packer is fastened to outer pipe by lower end thereof. Lower packing mechanism is identical to upper one. Lower packing mechanism is coaxially arranged upside down below upper packing mechanism. Upper and lower packing mechanisms have common outer and inner pipes. Pipe with radial orifices of lower packing mechanism is threadedly connected to stem including lower sealing means of inner pipe installed in stem interior.

EFFECT: increased quality and decreased production string sealing time.

2 cl, 2 dwg

FIELD: oil and gas production.

SUBSTANCE: whole process comprises primarily exposing well on polymer-chalk mortar, perforating bottom zone of formation under polymer-chalk mortar layer, creating acid-degradable protective shield in bottom zone by forcing polymer-chalk mortar under pressure exceeding specified cementation pressure by 10-15%. Thereafter, casing string is descended, annular space is cemented, and bottom zone of formation is re-perforated through casing string and protective layer is destroyed with acid. Polymer-chalk mortar has following composition, wt %: soda ash 1-6, carboxymethylcellulose 1-6, polyacrylamide 2-3, clay 48-52, chalk 46-50, water - the balance.

EFFECT: increased productivity of formation due to prevented negative action of drilling fluids and appearance of softened bottom zone.

FIELD: methods or devices for cementing, for plugging holes, crevices, or the like for well construction and workover.

SUBSTANCE: method involves primary exposing productive reservoir; preparing casing pipe for lowering in well; lowering casing pipe provided with shoe, check valve and baffle plate in well; performing direct casing pipe cementing through the shoe along with following cement mix, baffle plug and two portions of displacement liquid injection so that density of the first displacement liquid portion exceeds that of the second one to obtain summary hydrostatic pressure of above two portions in casing pipe greater than productive bed pressure; waiting for cement mix hardening; performing pressure testing of casing pipe; secondary exposing productive reservoir with perforation operation; providing productive reservoir inflow. Casing pipe preparation includes covering of inner and sections of outer casing pipe surfaces arranged within perforation interval with heat-insulation material so that heat insulation layer extends at least from shoe to the first displacement liquid portion level. Before cement mix injection buffer liquid is additionally injected in well. Lubrication hydrophobic liquid in injected in well between cement mix and buffer plug injection. Amount of lubricating hydrophobic liquid is equal to casing pipe volume defined by baffle plate and check valve and summed with reserve volume corresponding to casing pipe section length spaced 1-3 m below check valve. The casing pipe is covered with several heat insulation layers. Maximal total heat insulation layer thickness is selected with taking into consideration of free cylindrical former passage through the casing pipe and possibility of casing pipe fishing from outside with elevator. Minimal heat insulation layer thickness is 0.5 mm. Cement mix is injected in two portions. The second portion is supplied in amount equal to hole annuity volume around casing pipe and inner casing pipe volume defined by baffle plate and shoe additionally has swelling additive.

EFFECT: extended time of water-free well operation, decreased quantity of well workover for water shutoff, prevention of asphalt-tar-paraffin deposit generation in bottomhole reservoir zone, improved bottomhole reservoir zone treatment, extended range of suitable compositions, including corrosive compositions, to be used.

3 cl, 1 ex, 2 tbl, 2 dwg

FIELD: deep well drilling for water, oil and gas production, particularly special methods or apparatus for drilling.

SUBSTANCE: well construction device comprises body with central channel, centrator having blades aligned with drill bit legs, two nozzles having the same diameters and arranged in centering blades in common plane transversal to central channel axis and hydraulically communicated with it. Nozzle axes cross each other at 90° angle. Jet rock bit is installed under the body. Annular grooves are made in centering body blades and extend along outer diameter thereof at level of nozzle locations with respect to longitudinal body axis. Point of nozzle axes intersection is in circle with diameter equal to jet rock bit spaced 2dn distance therefrom. Distance between nozzle ends and nozzle axes intersection is equal to 4-5dn, where dn is nozzle orifice diameter.

EFFECT: increase well wall air-tightness and strength in permeable ground, increased reliability and provision of impervious screen forming inside matrix solid material.

FIELD: oil and gas production.

SUBSTANCE: invention relates to grouting mortars used for cementing casing pipes of gas, gas-condensate, and oil wells complicated by presence of formations with low hydraulic rupture pressure as well as presence of permafrost rocks. Light-weight grouting mortar contains 47.0-60.0% special-type cement, 6.6-11.8% clinoptilite as light-weight additive, and water. As a result, casing-pipe annulus incidents during boring and running wells are avoided owing to improved parameters of grouting cement, in particular increased sedimentation stability of mortar, dimensional stability and needed strength of cement stone at low positive and negative temperature in early hardening stages are achieved at simultaneous lowering of grouting mortar density.

EFFECT: improved performance characteristics of grouting mortar.

1 tbl

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