RU2547870C1 - Device to divide borehole to separate sections - Google Patents

Abstract

FIELD: oil-and-gas industry.SUBSTANCE: proposed device comprises pipes with lengthwise corrugation with sealing elements, upper and lower cylindrical sections of the pipe, top section thereof being provided with sealed piston with retainer. Bottom cylindrical section is provided with fixed bush from bellow. Nipple is fitted in the latter with the help of seals and provided with valve. From above, it is connected by link with said piston. Said pipes with lengthwise corrugation feature six-beam design and can be expanded to working size by internal pressure. Sealing elements are composed of closed elements filling the recesses with pipe beams. Temporary circular bulge is made between lower cylindrical section and said fixed bush. Nipple seals are composed of self-sealing inflatable resilient element. Above the latter cone expanding upward with outer spring-loaded plates to interact with said temporary circular bulge and to displace relative to said cone. Plane minimum diameter is smaller than inner contracted sections of the device. Clutch is arranged above said cone to interact with power pipe beams from inside at transportation position. End of upper cylindrical section of the device is provided with lengthwise grooves while sealed piston has ledges for lengthwise grooves.EFFECT: sealed casing string-borehole annuity in single trip.2 cl, 2 dwg

Description

The invention relates to the oil and gas industry, in particular to the development and operation of oil reservoirs with zones of different permeability, including in horizontal, multilateral wells and sidetracks, possibly using technology of simultaneous-separate operation.

It is known (patent RU No. 2083798, IPC ЕВВ 33/12, publ. 07/10/1997) a device for uncoupling reservoirs in a well, containing threaded profile pipes equipped with cylindrical end sections that are externally upset in their middle part, equipped with closed rims and filled in depressions with a sealing compound.

The disadvantages of this device are:

- when using double-beam pipes, the lack of sealing in the conjugation of the side sections of the profile pipe and the borehole wall, since the pairing of the lateral sections of the double-beam pipe and the borehole wall remains without a sealant because bitumen mastic does not propagate in the cross section, therefore, conditions are created for fluid breakthrough;

- reduced bore, as the rims prevent the full expansion of the two-beam profile pipe in the well;

- the need for a packer installed inside the device for sealing the annular space, which leads to an increase in the cost of the device as a whole;

- the need for expansion during installation of the device, which requires significant costs for the use of flare, as well as additional time.

The closest in technical essence and the achieved result is a device for uncoupling an open wellbore into separate sections (patent RU No. 2487231, IPC ЕВВ 33/12, published on July 10, 2013, bull. No. 19), including connected longitudinally-corrugated pipes with sealing elements located in areas with a smaller circumference described, the upper and lower cylindrical sections, the upper of which is equipped with a sealed piston with a clamp, and the lower cylindrical section is provided with a non-expandable sleeve from below, into the internal cavity the nipple equipped with a valve and connected from above by a rod with a piston is hermetically inserted with the possibility of movement, and the sealing elements of the profile pipes are made closed along the pipe perimeter, and their end sections connected by welding are made in the form of longitudinally corrugated calibrated sockets with a described diameter, large or equal to the described diameter of the sealing elements, while the thickness of the sealing elements and the distance between them are made with the possibility of their distribution without mutual overlap when expanding by a flare after straightening by internal pressure.

The upper and lower cylindrical sections may be provided with cylindrical nozzles installed between the cylindrical sections and longitudinally corrugated pipes and provided with sealing elements from water-oil-swelling rubber provided in the middle part, while the cylindrical nozzles are provided with cylindrical nozzles at the ends with a diameter greater than or equal to the outer diameter of the sealing element before it swells.

The disadvantages of this device:

- when installing the device provides additional tripping for flaring, which requires significant costs for the use of flare, as well as additional time for flaring, which leads to a rise in the cost of the device as a whole;

- the use of a rigid nipple with cuffs eliminates its reduction in diameter, which leads to the necessity of using a non-expandable cylindrical sleeve with a reduced bore;

- the absence of protrusions on the sealed piston, interacting with the longitudinal grooves of the end face of the upper cylindrical section of the device, eliminates the cranking of the device with a drill pipe string when it is difficult to lower it into horizontal wells.

The technical task of the proposed device is: ensuring the tightness of the overlapping device annular space without additional mechanical expansion, a slight decrease in the bore due to the use of self-sealing inflated elastic element, the ability to rotate the device when it is difficult to run, in particular in horizontal wells.

The technical problem is solved by a device for separating an open wellbore into separate sections, including longitudinally corrugated pipes with sealing elements, upper and lower cylindrical pipe sections, the upper of which is equipped with a sealed piston with a retainer, the lower cylindrical section from the bottom is equipped with a non-expandable sleeve into the inner cavity of which a nipple equipped with a valve and connected from above by a thrust with a piston is inserted tightly by means of seals with the ability to move; The profile pipe parts are located on the outside.

New is that longitudinally corrugated pipes are made six-beam with the possibility of expanding to a working size by internal pressure, and the sealing elements are made in the form of closed elements sequentially installed along the length filling the recesses between the pipe beams, and a technological ring is made between the lower cylindrical section and the non-expandable sleeve expansion, while the nipple seals are made in the form of a self-sealing inflated elastic element, above which is located upwardly expanding cone with external rams spring-loaded upwardly capable of interacting in a transport position with technological annular expansion and limited longitudinal movement relative to the cone, the smallest diameter of the rams being made smaller than the internal narrowed portions of the device, a coupling configured to interact with the lower tube beams is installed above the cone devices from the bottom inside in the transport position, while the end face of the upper cylindrical section of the device is provided wives with longitudinal grooves, and the sealed piston with protrusions under the longitudinal grooves.

Also new is the fact that the sealing elements of longitudinally corrugated pipes are made of oil or water-swelling rubber.

Figure 1 shows a device with an axial section; figure 2 - remote element A.

A device for separating an open wellbore into separate sections (hereinafter referred to as the device) includes longitudinally corrugated pipes 1 (see FIG. 1), made six-beam with the possibility of expanding to a working size by internal pressure with sealing elements 2, made in the form of sequentially installed along the length closed elements filling the recesses between the beams of the pipe 1. The upper cylindrical section 3 is equipped with a sealed piston 4 (see figure 2) with a latch 5. The end face 6 of the upper cylindrical section 3 of the device with lined with longitudinal grooves 7, and the sealed piston 4 with protrusions 8 under the longitudinal grooves 7. The lower cylindrical section 9 (see Fig. 1) is equipped with a non-expandable sleeve 10 from below, into the internal cavity of which a self-sealing inflated elastic element is sealed with the possibility of movement 11, equipped with a valve 12. Above the inflated elastic element 11, there is a upwardly expanding cone 13, connected from above by a thrust 14 with a piston 4, with external upwardly spring-loaded dies 15, made with the possibility of mutual action in the transport position with a technological annular extension 16 and a limited longitudinal movement relative to the cone 13. The smallest diameter of the dies 15 is smaller than the internal narrowed sections of the device. A clutch 17 is installed above the cone 13, having the ability to interact from below from the inside with the beams 18 of the lower pipe 19 of the device in the transport position.

For additional sealing, the sealing elements 2 of the longitudinally corrugated pipes 1 are made of oil or water-swelling rubber.

Device application example

On the pipe string, the complete assembly is lowered into the interval of the well that needs to be disconnected (not shown). Due to the fact that the end face 6 of the upper cylindrical section 3 of the device is provided with longitudinal grooves 7 (see FIG. 2), and the sealed piston 4 has projections 8 under the longitudinal grooves 7, it is possible to rotate the device when it is difficult to lower it. Due to the fact that the coupling 17 (see Fig. 1) abuts from the inside to the beams 18 of the lower pipe 19 when the device is lowered into the well, the axial force from the valve 12 is not transmitted through the rod 14 to the sealed piston 4. The six-beam pipes 1 are expanded by hydraulic pressure to the working size, while the sealing elements 2, nestling sections 20 located between the beams of the pipe 1, seal annular space. In this case, the axial force on the self-sealing inflated elastic element 11 is balanced by the cone 13 located above with the outer rams 15 spring-loaded, located in the technological annular extension 16 and abutted in the bevel 21 of the non-expandable sleeve 10. Then, the drill pipe string generates an upward axial force with a simultaneous increase in pressure inside the device. In this case, the sealed piston 4, expanding the retainer 5, leaves the upper cylindrical section 3. The assembly connected by the thrust 14, consisting of the piston 4, the cone 13 with the dies 14, the self-sealing inflated elastic element 11 provided with the valve 12, is moved upward through the device and lifted surface. In this case, the dies 15 during the upward stroke, as well as the inflated elastic element 11, decrease in diameter when passing in the bottlenecks of the device, without interfering with the lifting of the assembly to the surface.

Due to the fact that the sealing elements 2 of the longitudinally corrugated pipes 1 (see Fig. 1) are made of oil or water-swelling rubber, the reliability of isolation between the walls of the well and the device is increased.

The device provides tightness of the annular space overlap in one round trip without additional mechanical expansion, a slight decrease in the bore due to the use of self-sealing inflated elastic element 11 and has the ability to pass into horizontal wells.

Claims (2)

1. A device for separating an open wellbore into separate sections, including longitudinally corrugated pipes with sealing elements, upper and lower cylindrical pipe sections, the upper of which is equipped with a sealed piston with a clamp, the lower cylindrical section from the bottom is equipped with a non-expandable sleeve, into the inner cavity of which is hermetically sealed with the help of seals, a nipple equipped with a valve and connected from above by a rod with a piston is inserted with the possibility of movement, and the sealing elements of the profile pipes are displaced laid on the outer surface, characterized in that the longitudinally corrugated pipes are made six-beam with the possibility of expanding to a working size by internal pressure, and the sealing elements are made in the form of closed elements sequentially installed along the length, filling the recesses between the pipe beams, and between the lower cylindrical section and non-expandable the sleeve is made of technological annular expansion, while the nipple seals are made in the form of a self-sealing inflated elastic an element above which there is a cone expanding upwards with external dies spring-loaded upwardly capable of interacting in a transport position with a technological annular expansion and of limited longitudinal movement relative to the cone, the smallest diameter of the dies being made smaller than the internal narrowed portions of the device; a coupling configured to interaction with the rays of the lower pipe of the device from the bottom from the inside in the transport position, while the end face of the upper cylinder The device is equipped with longitudinal grooves, and the sealed piston has protrusions under the longitudinal grooves. 2. The device according to claim 1, characterized in that the sealing elements of the longitudinally corrugated pipes are made of oil or water-swelling rubber.

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