RU2653216C1 - Method and device for research and operation of horizontal well with zones of permeability variations - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: group of inventions refers to the oil and gas production industry, namely to the methods of development and operation of wells with zones of different permeability. Method includes drilling a horizontal well and cementing the casing. In the formation, zones with different permeability are determined. String of pipes is lowered into the well, from below, equipped with a check valve and packers from the outside, made in the form of patches, communicated with a string of pipes and installed taking into account the length of the zones with a corresponding permeability, one end of which is rigidly fixed to the pipe string, and the other is movable along the pipe string. Packers are installed after descent into the well by creating high pressure inside the pipe string and patches. Zones with different permeability are operated in sequence from the face to the mouth before the corresponding zones are watered, beginning with operation through a check valve, then after a series of perforations of the pipe string opposite the corresponding zone. Isolation of watered zones is carried out by installing a packer plug inside the pipe string before opening by perforating the next zone. Column of pipes after installation of packers is designed for successive perforation from the face to the mouth to open the corresponding zones after overlapping the previous opened by the encircled water zone with a stopper.

EFFECT: reduces the likelihood of emergencies due to exclusion of mechanical filter opening and closing operation, exclusion of narrowing of the inner diameter of the casing string and consequently, exclusion of difficulties when the tool is lowered into the well for carrying out technological operations, exclusion of additional lifting and lifting operations.

2 cl, 2 dwg

Description

The invention relates to the oil and gas industry, and in particular to methods of isolating zones of complications during drilling and well repair.

It is known “Device for a formation with zones of different permeability” (patent for utility model RU No. 94628, IPC ЕВВ 43/14, 33/13, 43/12 publ. In Bulletin No. 15 of 05/27/2010), containing a casing with packers intended for installation within patches designed to isolate zones with low permeability, and the device also includes valves located between the packers and capable of being controlled from the mouth, each of which is made in the form of a housing with passage holes and an axially movable sleeve made with the possibility opening and closing holes in extreme positions and equipped with a restriction, filters are placed on the outside of the valves, while the process column is equipped with a pusher pressed down by a spring, the force of which exceeds the shear force of the sleeve, a nozzle with an annular protrusion, the outer diameter of which is larger than the passage diameter of the corresponding narrowing of the sleeve, but less than the same passage diameters of the narrowing of the sleeve further located from the bottom of the well, and to move the sleeve up the technological columns and it is equipped with a grip made in the form of a housing with balls drawn by springs outside, the diameter of the circumscribed circle around which is larger than the passage diameter of the corresponding sleeve narrowing, but smaller than the similar passage diameters of the sleeve narrowings further located from the bottom of the well, and the spring force is sufficient to shift the corresponding sleeve with balls .

The method carried out using this device includes drilling a well, lowering a casing string with packers and valves between them and installing a device with the packers placed within the patches located in the open hole, with separation of formation zones with different permeability, to move the sleeve down the technological string is lowered into the well, while the pusher passes the valves overlying from the bottom until it stops in the corresponding narrowing of the sleeve, which moves down under the weight of the technological count When the lower end position is reached by the sleeve, the spring is compressed, and the production string is unloaded to narrow the sleeve, after which the production string with a pusher is removed from the well, and to move the sleeve up, the production string is lowered into the well, and the gripper passes the valves upstream from the bottom to stop it in the corresponding narrowing of the sleeve, which rests on the stop, under the weight of the technological column, the balls, interacting with the chamfers of the corresponding narrowing, compress the spring and recess I into the capture housing, after which the balls undergo this narrowing, then the capture for guaranteed passage of the ball through the narrowing of the sleeve is lowered down by 0.5-1.5 m, followed by lifting up, as a result, the balls abut from the bottom of the face to narrow the corresponding sleeve, raising it to the upper extreme position, after which, under the force of the lifting mechanism, which pulls the process column up, the balls, interacting with the chamfers of the corresponding narrowing, compress the spring, are sunk into the gripper body and pass this narrowing, last which process with capture column is extracted from the borehole.

The disadvantages of the method and device are:

- additional costs for launching the column with valves and packers with the installation of the latter in plasters pre-installed in the wellbore to isolate zones with low permeability;

- the complex design of the valves, which can lead to an emergency if they fail;

- a significant narrowing of the wellbore due to the installation of adhesives and packers in them, as well as the narrowing of the inner diameter of the casing string due to the presence of bushings with contractions and a nozzle with an annular protrusion, which can lead to difficulties when lowering the tool for carrying out technological operations;

- the need to use sophisticated equipment to open and close valve sleeves, which can lead to an emergency if they fail;

- additional costs for launching the process string for opening and closing valve sleeves.

The closest in technical essence is the method of developing a horizontal wellbore of a formation with zones of different permeability (patent RU No. 2485290, IPC ЕВВ 43/14, published in Bulletin No. 17 of 06/20/2013), including drilling a horizontal well and cementing the casing to the top of the formation, determination of zones with different permeability in the formation, descent of the pipe string into the well with filters made with the possibility of mechanical opening and closing from the inside, and packers from the outside, installation of packers with separation of filters in the open hole and zones fins with different permeability, determining the productivity and watering of zones by successively opening and closing filters located opposite the corresponding zone of the formation, determining zones with close permeability and combining them into groups, operating the well one by one from each group, opening the filters corresponding to the group and closing the others, with increasing the water content in one of the groups defines the zone with the highest water content by successively closing and opening the corresponding filters in group, treatment of the zone with the highest permeability with a water-insulating composition or complete closure of the corresponding filter, continued operation of the well in the previous mode, technological exposure of the zone treated with a water-insulating composition, the call of inflow from this zone and operation with zones having a close permeability to it.

The closest in technical essence is a device for implementing the method (patent RU No. 2548465, IPC ЕВВ 43/14, published in Bulletin No. 11 of 04/20/2015), including a pipe string equipped with filters with the possibility of opening and closing from the inside and packers on the outside, made in the form of adhesives, installed taking into account the length of the zones with the corresponding permeability, one of the ends of which is rigidly fixed to the pipe string, and the other is made with the possibility of movement along the pipe string and connected to a protective perforated casing installed on the outside the filter with the overlapping of its openings and made with the possibility of combining the holes of the filter and the casing due to displacement of the casing when straightening the plasters under the action of fluid pressure generated in the pipe string, the plasters being sealed from the outside and from the inside with a pipe connection through a check valve installed at the communicating hole, while the lower filter remains open during the descent of the device, and after being fixed in the production casing, it is closed and the patch is straightened and fixed it in the well by creating fluid pressure, in addition, the check valves are made with the possibility of eliminating the straightening of the patches during the descent of the device with flushing.

The disadvantages of the known method and device are:

- the likelihood of an emergency, since there is a risk of jamming and malfunctioning of mechanically open and close filters;

- narrowing of the inner diameter of the casing string due to the presence of bushings or shutters for blocking the filters, which may lead to difficulties when lowering the tool for carrying out technological operations;

- additional costs for tripping to close the lower filter, which remains open during the descent of the device, after which the plasters are fixed in the well by creating a fluid pressure.

The technical objectives of the invention are the creation of a method and a simple, reliable design of the device, which reduces the likelihood of an emergency by eliminating the mechanical opening and closing of the filters, eliminating the narrowing of the inner diameter of the casing and, accordingly, eliminating difficulties when lowering the tool into the well for technological operations, exceptions for additional tripping to close the lower filter due to the presence in the lower parts of the relief valve instead of the lower filter.

Technical problems are solved by a method for researching and operating a horizontal well with zones of different permeability, including drilling a horizontal well and cementing the casing to the roof of the formation, determining zones with different permeability in the formation, lowering the pipe string with packers from the outside into the well, installing packers with uncoupling of the formation zones with different permeability in the horizontal well, operation of zones with different permeability with sequential isolation of zones with the highest water cut.

What is new is that before the descent, the pipe string is equipped with a check valve from below, and the packers are made in the form of plasters connected with the pipe string and installed taking into account the length of the zones with the corresponding permeability, one end of which is rigidly fixed to the pipe string and the other is made with the possibility of movements along the pipe string, with the packers being installed after descent into the well by creating high pressure inside the pipe string and packers, zones with different permeability are operated sequentially from the bottom to the bottom Strongly before flooding the respective zones, starting with the operation of the check valve and then after the sequential perforation of the pipe string opposite the respective zone, wherein the isolation is carried watered zones setting packer plug inside the pipe string prior to opening the next perforation zone.

Technical tasks for implementing the method are also solved by a device for researching and operating a horizontal well with zones of different permeability, including a pipe string with a bypass valve from below, equipped with packers from the outside, and the packers are made in the form of plasters communicated with the pipe string and installed taking into account the length of the zones with the corresponding permeability, one of the ends of the patch is rigidly fixed to the pipe string, and the other is installed with the ability to move along the pipe string when straightening patches under tviem fluid pressure created in the pipe string.

What is new is that the bypass valve is made in the form of a check valve that passes into the pipe string, which, after installing the packers, is capable of sequentially perforating from the bottom to the mouth to open the corresponding zones after the previous opened waterlogged area has been closed with a packer plug.

In FIG. 1 shows operation through a check valve farthest from the mouth of the zone to its flooding.

In FIG. 2 shows the operation of the next zone after perforation of the pipe string opposite the corresponding zone and isolation of the waterlogged area by installing a packer plug inside the pipe string.

A device for researching and operating a horizontal well 1 (Fig. 1, 2) with zones of different permeability 2, 3 includes a pipe string 4 with a bypass valve 5 from below, made in the form of a check valve that passes inside the pipe string 4. The pipe string 4 is equipped with packers from the outside made in the form of plasters 6 in communication with the column of pipes 4 and installed taking into account the length of the zones with the corresponding permeability 2, 3. One of the ends of the strip 6 is rigidly mounted on the pipe string 4, and the other is installed with the possibility of movement along the pipe string UB 4 when straightening the patches 6 under the action of fluid pressure generated in the pipe string 4. After fixing the patches 6, the pipe string 4 is capable of sequential perforation 7 (Fig. 2) from the bottom 8 (Fig. 1, 2) to the mouth (not shown ) for opening the corresponding zones after overlapping the previous opened waterlogged zone with a packer plug 9 (Fig. 2).

The method is implemented in the following sequence.

After drilling the well 1 (Fig. 1, 2), it is secured by the casing 10 above the reservoir 11. The formation 11 is opened by drilling a horizontal section 12. Then, geophysical studies reveal zones of low 2 and high 3 permeability in the reservoir 11. Next, a descent is made into the horizontal section 12 of the device for research and exploitation of the horizontal well 1. In this case, through the bypass valve 5, made in the form of a check valve, the pipe string 4 is filled when it is lowered into the well 1. After the device reaches the design depth, it is fixed in the casing 10, for example, using a packer, longitudinally-corrugated suspension, and the like. Then in the pipe string 4 with a mud pump with a flow rate of 12-15 l / s create fluid pressure, packers made in the form of adhesives 6, straightening, are fixed in a horizontal section 12. At the same time, adhesives 6 are positioned so that they isolate zones with low 2 and high 3 permeability of the horizontal section 12 from each other.

The development of the well 1 is carried out by any known method, while the distant section 13 works through the bypass valve 5, made in the form of a check valve. After section 13 is flooded or the flow rate of the liquid is unprofitable, the packer plug 9 (Fig. 2) is lowered and installed in the interval of the distant patch 6 (Fig. 2) and block section 13 (Fig. 1, 2) from the bottom 8 to the packer plug 9 (Fig. 2). After that, perforation 7 of the next zone 3 (Fig. 1, 2) is made between the distant patch 6 and the next patch 6 ¹ . Development and exploitation of the opened zone 3 is carried out. Similarly, all zones 2 and 3 of the horizontal section 12 of well 1 are shut off, mastered and exploited.

The method and device can reduce the likelihood of emergency situations by eliminating the mechanical opening and closing operations of the filters, eliminating the narrowing of the inner diameter of the casing and thereby eliminating difficulties when lowering the tool into the well for technological operations, eliminating the additional tripping operation to close the lower filter beyond due to the presence in the lower part of the bypass valve instead of the lower filter.

Claims (2)

1. A method for researching and operating a horizontal well with zones of different permeability, including drilling a horizontal well and cementing the casing to the roof of the formation, determining zones with different permeability in the formation, lowering the pipe string with packers from the outside into the well, installing packers with uncoupling the formation zones with different permeability in the horizontal trunk, the operation of zones with different permeability with sequential isolation of the zones with the highest water cut, characterized in that before the descent the bottom of the pipe is equipped with a check valve, and the packers are made in the form of plasters in communication with the pipe string and installed taking into account the length of the zones with the corresponding permeability, one of the ends of which is rigidly fixed to the pipe string and the other is arranged to move along the pipe string, they are installed after descent into the well by creating high pressure inside the pipe string and adhesives, zones with different permeability are operated sequentially from the bottom to the mouth to the flooding of the corresponding zones starting from operation through a non-return valve, and then after successive perforation of the pipe string, opposite the corresponding zone, and isolation of waterlogged zones is carried out by installing a packer plug inside the pipe string before opening the next zone with perforation. 2. A device for researching and operating a horizontal well with zones of different permeability, including a pipe string with a bypass valve from below, equipped with packers from the outside, the packers being made in the form of adhesives connected to the pipe string and installed taking into account the length of the zones with the corresponding permeability, one of the ends the patch is rigidly fixed to the pipe string, and the other is mounted with the ability to move along the pipe string when straightening the plasters under the influence of the fluid pressure generated in the pipe string, ex characterized in that the bypass valve is made in the form of a check valve passing into the pipe string, which, after the packers are installed, is capable of sequentially perforating from the bottom to the mouth to open the corresponding zones after the previous opened waterlogged zone is blocked by a packer plug.

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