RU2578095C1 - Method for isolation of water flow in open horizontal section producing wells - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention finds application in water shutoff in a horizontal or inclined sections of trunks wells. Method of isolation of inflow of water in the open horizontal section of the production well involves extraction from wells pumping equipment, the descent of the pipe string in the well, injecting through them waterproofing solution hardening properties, the creation of an impermeable screen range water-revealing formation and subsequent leaching of waterproofing solution from wells by reverse circulation after initial setting waterproofing compound. After removal from the production well pumping equipment is carried out geophysical survey and determine water-revealing formation interval length in the horizontal section of open hole wellbore. Then openhole horizontal section of the wellbore tubular string is lowered further, the guide funnel fitted on top and the sealing packer. Following additional sealing packer pipe string is equipped with two water-swellable packers length of 1 m each, interconnected by a perforated pipe length equal to the length of the interval water-revealing formation. Inside the tubing for additional perforated pipe installed retainer. Thus after further lowering the pipe string into the open horizontal section of the wellbore and landing sealing packer swellable packers are placed on the interval boundaries water-revealing formation. After waiting swelling packer pipe string lowered into the wellbore. Waterproofing solution is pumped along the pipe string through the holes in the pipe perforation interval water-revealing formation to form a waterproofing screen. After that the injection of the washing liquid with the creation of reverse circulation waterproofing eluted solution from the pipe string more wells. Produce more perforations of the pipe string before and after the interval boundaries water-revealing formation. Then, in the well at the end of the pipe string lowered hydraulic disconnector expandable sleeve and a check valve that passes from the bottom to the wellhead. This expandable sleeve at the ends equipped with sealing rings. Launching process pipe string into the well to carry out the interaction with the expandable sleeve retainer. After that, the process pipe string is pressurized and produce outward radial expansion of the sleeve to seal the end seals further perforated pipe tubing string. Then disconnect the hydraulic isolator produce expandable sleeve by the extraction process and produce a tubing string with a hydraulic disconnect from the well, lowered into the well pumps and run well in a job.

EFFECT: technical result is to increase the reliability and efficiency of the process, improve the quality of waterproofing work, with the exception of watering the horizontal section of the wellbore interval water-revealing formation.

1 cl, 5 dwg

Description

The invention relates to the field of oil and gas industry and will find application in the isolation of water inflows in horizontal or inclined sections of the shafts of production wells.

A known method of repair and insulation work in a horizontal section of a wellbore (patent RU No. 2379472, IPC ЕВВ 33/13, published on January 20, 2010, bull. No. 2), which includes extracting pumping equipment from a well, lowering a pipe string into the well, pumping through water-insulating solution with hardening properties and subsequent leaching of the water-insulating solution from the wellbore, and first, the pipe string is equipped with a hydraulic nozzle and plug for the tube, with openings communicating the space inside the tubing and tubing l of the well, through these holes, first a highly viscous hydrophobic water-insoluble composition is pumped into the insulated interval, then a cement mortar based on cement grade IG with a water-cement ratio of 0.44, a plug with a destructible diaphragm overlapping the through inner channel is installed, then squeezing fluid is pumped until the plug is placed on the saddle, raise the pipe string to a safe area, and after the cement slurry has thickened to a consistency of 100 Vs, the pipe string is lowered and the pressure in the pipes is raised it squeezing fluid to fracture the diaphragm, whereupon cement is eluted from the wellbore by pumping the washing liquid with the retarder of cement slurry through the pipe string through jetting nozzle.

The disadvantages of this method are:

- firstly, a complex process of implementing the method associated with the sequential injection of a highly viscous hydrophobic water-insoluble composition, cement mortar, as well as squeezing liquid;

- secondly, the low efficiency of repair and insulation works in the horizontal section of the wellbore, due to the short duration of the waterproofing effect by injecting a highly viscous hydrophobic water-insoluble composition and cement mortar;

- thirdly, the low reliability of the implementation of the method associated with the mandatory implementation of a number of consecutive technological operations, in this case, a plug with a destructible diaphragm overlapping the through inner channel is installed, then squeezing liquid is pumped until the plug is seated on the saddle, the pipe string is lifted to a safe area, after the thickening of the cement mortar to a consistency of 100 Vs, the pipe string is lowered and the pressure in the pipes is raised by pumping the squeezing fluid until the diaphragm ruptures. All these are technological operations dependent on each other, and if one of them is violated, for example, when the cement mortar thickens to a consistency of less than 100 Vs, the implementation of the whole method is frustrated.

The closest technical solution to the proposed one is a method of isolating the influx of water in an uncased horizontal section of the wellbore of a producing well (patent RU No. 2273722, IPC ЕВВ 33/13, publ. 04/10/2006, bull. No. 10), including extraction of pumping equipment from the well, descent columns of tubing into the well, pumping through them a water-proofing solution with hardening properties, while opposite the intervals of water-producing strata form an impenetrable crust, for which cement is used as a water-proofing solution solution, modified with polyvinyl acetate reagent in an amount of 0.25-0.5% by weight of cement, with a volume that ensures filling the annular space of the uncased horizontal section through the tubing string, deflated to the bottom of the horizontal section of the wellbore, and holding for 2-3 hours with its subsequent washing out of the annulus by direct or reverse circulation after the start of cement setting.

The disadvantages of this method are:

- firstly, low reliability, which is associated with the rapid destruction of an impermeable crust (water barrier) in the interval of the water-producing formation installed in the uncased horizontal section of the wellbore during subsequent operation of the well due to the lack of fastening of the wellbore in the isolated interval;

- secondly, the poor quality of fastening of waterproofing works, which is associated with the destruction of an impermeable crust (waterproofing screen) in the interval of a water-producing formation installed in an uncased horizontal section of the wellbore of a producing well, due to the depression in the well during development and subsequent operation;

- thirdly, the low efficiency of the implementation of the method associated with the short-term effect of creating an impermeable crust (insulation) in the intervals of the water-producing strata, since during subsequent operation, water from the water-producing stratum breaks into either an uncased horizontal section of the wellbore by circumventing an impermeable crust, or water from the water-producing layer through an impenetrable crust flows into other oil-bearing intervals of the horizontal section of the wellbore, causing them to prematurely waterlogging;

- fourthly, after the destruction of the insulation and its falling into the uncased horizontal section of the wellbore, there is a more intensive flooding of the uncased horizontal section of the wellbore from the intervals of the developing reservoir.

The technical task of the proposal is to increase the reliability and efficiency of the method by improving the quality of waterproofing works and eliminating the flooding of the uncased horizontal section of the wellbore from the intervals of the developing reservoir.

The problem is solved by isolating the influx of water in an uncased horizontal section of the wellbore of the producing well, including extracting pumping equipment from the well, lowering the pipe string into the well, pumping a water-proofing solution with hardening properties through them, creating an impermeable screen in the interval of the water-developing formation and then washing out the water-proofing solution from wells with reverse circulation after the start of the setting of the waterproofing composition.

New is that after extraction of pumping equipment from a production well, geophysical studies are carried out and the length of the water-producing formation interval is determined in the uncased horizontal section of the wellbore, then an additional pipe string is lowered into the uncased horizontal section of the wellbore, equipped with a guide funnel and a sealing packer on top, below the sealing packers an additional pipe string is equipped with two water-swellable packers 1 m long each, connected between a perforated nozzle with a length equal to the length of the interval of the water-producing formation, and a latch is installed inside the additional pipe string behind the perforated pipe, after which the additional pipe string is lowered into the open horizontal section of the wellbore and the packing packer is seated, swellable packers are placed at the boundaries of the water-producing formation interval, after waiting swelling packers lower the pipe string into the well, inject the waterproofing solution through the pipe string through the hole I perforation pipe in the interval of the water-producing formation with the formation of a water-proof screen, after which by pumping the washing liquid with the creation of reverse circulation, the water-insulation solution is washed out of the additional pipe string of the well, the additional pipe string is perforated before and after the boundaries of the interval of the water-producing formation, then into the well at the end of the pipe string lower the hydraulic disconnector with an expandable sleeve and a check valve, passing from the bottom to the wellhead, while expanding the removable sleeve at the ends is equipped with o-rings, the technological pipe string is lowered into the well until the expandable sleeve interacts with the clamp, after which excess pressure is created in the pipe technological string and the sleeve is radially expanded outward until the ends of the perforated pipe of the additional pipe string are sealed with sealing rings, after which disconnect the hydraulic disconnector from the expandable sleeve and remove the process pipe string from the hydraulic disconnect it from the hole, lowered into the well pumps and run well in the job.

In FIG. 1, 2, 3, 4 and 5 schematically and sequentially depict the proposed method of isolating the influx of water in an uncased horizontal section of the wellbore.

The proposed method is carried out in the following sequence.

Pumping equipment is removed from the producing well 1 (hereinafter referred to as the well) with an uncased horizontal portion of the barrel 2 (see FIG. 1).

Geophysical studies are carried out in an uncased horizontal section of the wellbore 2, for example, using an integrated geophysical device of the type AGAT-KG-42-6V and the interval 3 of water inflow from the water-developing formation 4 is determined.

To do this, a geophysical instrument is lowered into an uncased horizontal section of wellbore 2, for example, 300 m long of a well 1 on a flexible pipe with a stored cable, the phase composition is determined from the horizontal wellbore profile at the multiphase composition of the produced products, and the length L of the interval 3 of the water-developing formation 4 of uncased horizontal section of the barrel 2 of the well 1 to be waterproofed, for example, the length L is 8 m and is in the range of 207-215 m

An additional pipe string 5 is lowered into the uncased horizontal section of the wellbore 2 of well 1 (see Fig. 2), for example, which is a liner of 114 mm diameter pipes with a wall thickness of 7 mm according to GOST 633-80, for example, 350 m long, equipped with a top guiding funnel 6 and sealing packer 7.

An additional pipe string 5 is lowered into the uncased horizontal section of the wellbore 2 of the well 1, for example, on a pipe process pipe (not shown in FIGS. 1, 2, 3, 4 and 5), for example, a 73 mm tubing string according to GOST 633-80 with a hydraulic disconnector any known design (in Fig. 1, 2, 3,4, 5 not shown).

Guide funnel 6 (see Fig. 2) has a narrowing from top to bottom and provides entry into an additional pipe string 5 of the descent equipment.

The sealing packer 7 of any known design isolates the space between the well and the additional pipe string in the uncased horizontal section of the wellbore 2 of well 1, for example, the TSP4 Weatherfort packer.

The hydraulic disconnector can be of any known design, for example, the design of the TatNIPIneft institute, patent RU No. 2425946 “Borehole disconnector”, IPC EV 21/06, publ. 08/10/2011, bull. Number 22.

Below the sealing packer 7, the additional pipe string 5 is equipped with two water-swellable packers 8 and 9, each 1 m long, interconnected by a perforated nozzle 10 with holes (shown in FIGS. 2, 3, 4, 5 conventionally) and a length H equal to the length L interval 3 (see Fig. 2 and 3) water-developing layer 4 (in Fig. 2, 3, 4, 5 shown conditionally).

Inside the additional pipe string 5 (see FIGS. 2 and 3), a latch 11 is installed behind the perforated pipe 10, for example, made in the form of a metal ring rigidly fixed with screws (not shown in FIGS. 1, 2, 3, 4, 5) to additional pipe string 5.

Water swellable packers 8 and 9 are made in the form of elastic sleeves 1 m long with an inner diameter of 114 m and, for example, an outer diameter of 133 mm.

As the pipe 10, a segment of the tubing according to GOST 633-80 is used, 8 m long.

The reliability of the implementation of the method is improved by eliminating the destruction of the isolation interval (water-proof screen 15) when creating depression in an uncased horizontal section of the barrel 2 of the well 1 by installing an additional pipe string (liner) 5 in the uncased horizontal section of the barrel 2 of the well 1.

After the additional pipe string 5 is lowered into the uncased horizontal section of the barrel 2 of the well 1, the hydraulic disconnector is activated and the process pipe string is disconnected from the additional pipe string 5 and the sealing packer 7 is seated in the well 1, while the swellable packers 8 and 9 are placed at the boundaries 12 (207-206 m) and 13 (215-216 m), respectively, of interval 3 of the water-developing formation 4. After that, the column of process pipes with a hydraulic disconnector is removed from the well 1. After waiting for the swelling, the packer in 8 and 9 (see Figs. 2 and 3), for example, a pipe string 14 (for example, a 73 mm tubing string according to GOST 633-80) is lowered into well 1 for 48 hours.

Any known water-proofing mortar, for example, IG-based cement mortar, is pumped and sold through a pipe string 14 through the holes of the perforation pipe 10 in the interval 3 of the water-developing formation 4 with the formation of the water-proof screen 15 in the interval 3 of the water-developing formation 4. The volume of injection of cement mortar for create a water-proof screen 15 in the interval 3 of the water-developing layer 4 is determined by the technological service of the repair enterprise, for example 2.5 m ³ .

The effectiveness of the method is improved by eliminating the possibility of bypassing the encoded interval (water barrier screen 15) with water from the water developing formation 4 by installing water swellable packers 8 and 9 at the boundary 12 and 13, respectively, of the interval of water inflow from the water developing formation 4 into the uncased horizontal section of wellbore 2 of well 1 .

After the start of the setting of the waterproofing composition in the interval 3 of the water-developing formation 4, the washing liquid is pumped, for example, waste water with a density of 1000 kg / m ³ with the creation of reverse circulation, i.e. by pumping the washing liquid into the well 1 through an additional pipe string 5 and by lifting the washing liquid through the pipe string 14, the waterproofing solution is washed out of the additional pipe string 5 of the well 1.

Pipe string 14 is removed from well 1.

Perforate 16 (see Fig. 4) and 17 of an additional pipe string 5 before and after the boundary 12 and 13, respectively, of interval 3 of the water-developing formation 4.

For example, alternate perforation of 16 and 17 is made by any known device, for example, using a single-use case punch, KPO-114.

In the well 1 at the end of the pipe string 14 (see FIG. 4), a hydraulic disconnector 18 (of any known design, for example of the same design as described above, but of a smaller size, which can move freely in the additional pipe string 5) with an expandable sleeve is lowered 19 and a check valve 20, passing from the bottom to the wellhead 1, while the expandable sleeve 19 at the ends is equipped with sealing (rubber) rings 21 'and 21' '. As a non-return valve 20 (conventionally shown in FIGS. 4 and 5), any known construction is used, for example, “Non-return valve for a well” described in RU patent No. 2418154, IPC ЕВВ 34/06, publ. 05/10/2011, bull. No. 13.

The descent of the pipe string 14 into the well 1 is carried out before the expandable sleeve 19 interacts with the latch 11. During the descent, the pipe string 14 is filled with the borehole fluid due to the open check valve 20 passing from the bottom to the wellhead 1.

After that, the pipe string 14 is refilled with a liquid, for example fresh water with a density of 1000 kg / m ³ , and an overpressure, for example 10 MPa, is created in the pipe string 14, while the check valve 20 closes, that is, it does not pass fluid from the expandable sleeve 19 into the well 1 Thus, the extension of the sleeve 19 to seal the sealing rings 21 'and 21 "of the ends of the perforated pipe 10 of the additional pipe string 5 is made.

After that, the hydraulic disconnector 18 is disconnected from the expandable sleeve 19 and the pipe string 14 with the hydraulic disconnector 18 is removed from the well 1.

The expandable sleeve 19 seals the inside of the hole of the perforated nozzle 10, due to this, when creating a depression in the well 1, during development and subsequent operation, the destruction of the impermeable crust (waterproofing screen 15) in the interval of the water-developing formation 4 is excluded, which improves the quality of waterproofing works.

The pumping equipment 22 is lowered into the well 1 (see FIG. 5) and the well 1 is launched into operation. During the operation of the well, the irrigation of the horizontal section of the wellbore 2 of the well 1 from the interval 3 of the water-developing formation 4 is excluded due to the exclusion of destruction of insulation from the interval 3 of the water-developing formation 4 into the uncased horizontal section of the well 2 of the well 1.

The proposed method allows you to:

- to increase the reliability and efficiency of the method;

- improve the quality of waterproofing;

- to exclude flooding of the horizontal section of the wellbore from the interval of the water-producing formation.

Claims (1)

A method of isolating the influx of water in an uncased horizontal section of the wellbore of a producing well, including removing pumping equipment from the well, lowering the pipe string into the well, injecting a waterproofing solution with hardening properties through them, creating an impenetrable screen in the interval of the developing layer and then flushing the waterproofing solution from the well with reverse circulation after the start of setting water-proofing composition, characterized in that after extraction of the pumping equipment from the production well Geophysical surveys are carried out and the interval of the water-producing formation is determined in the uncased horizontal section of the wellbore, then an additional pipe string is lowered into the uncased horizontal section of the wellbore, equipped with a guiding funnel and a sealing packer on top, and an additional pipe string is equipped with two water-swelling packers 1 each in length below the packing packer m each, interconnected by a perforated pipe with a length equal to the length of the interval the formation, and inside the additional pipe string, a retainer is installed behind the perforated pipe, and after the additional pipe string is lowered into the uncased horizontal section of the wellbore and the packing packer is seated, swellable packers are placed at the boundaries of the interval of the developing reservoir, after waiting for the packers to swell, the pipe string is lowered into the well, water-insulating solution is pumped through the pipe string through the holes of the perforation pipe into the interval of the water-producing formation with the formation m of the water-proofing screen, after which the water-proofing solution is washed out from the additional pipe string of the well by pumping the flushing fluid with the creation of reverse circulation, the additional pipe string is perforated before and after the boundaries of the interval of the water-producing formation, then a hydraulic disconnector with an expandable sleeve and a return pipe is lowered into the well at the end of the pipe string a valve passing from the bottom to the wellhead, while the expandable sleeve at the ends is equipped with o-rings, the th pipe string into the well is carried out before the expandable sleeve interacts with the retainer, after which excess pressure is created in the pipe production string and the sleeve is radially expanded outward of the sleeve until the ends of the perforated pipe of the additional pipe string are sealed with sealing rings, after which the hydraulic disconnector is disconnected from the expandable sleeve and produced removing the process string of pipes with a hydraulic disconnector from the well, pumping equipment is lowered into the well blowing and launch the well into operation.

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