RU2305750C1 - Packer - Google Patents

Abstract

FIELD: oil and gas industry, particularly devices for hermetical reservoir isolation.

SUBSTANCE: packer comprises body with central channel and connection pipe provided with shaped slot on outer surface thereof. Packer also has conical depression adjoining connection pipe, movable bush supported by connection pipe and having finger cooperating with shaped slot, as well as spring-loaded centralizer. Slips cooperating with conical depression are connected to spring-loaded centralizer ends. Packer includes upper and lower self-sealing sleeves, check valve, seating tool rigidly connected to tubing string and to body through shear members and hollow sealed rod. The hollow sealed rod comprises radial channels and telescopically slides inside central body channel. Seating tool is made as connection pipe and has rest on inner surface. Connection pipe interior communicates with ambient space. Conical depression of the body is made as upper and lower cones and connection pipe is arranged in-between. Opposite upper self-sealed sleeve and lower sleeve are located over upper cone and under lower cone correspondingly. Centralizer includes upper and lower centering members provided with differently-directed slips. Central channel of the body has restriction located in lower part thereof and receiving hollow rod so that the rod may perform limited axial movement. The rod is sealed over radial channels. Annular depressions, springing ring and sealing means are serially installed over the radial channels in bottom-top direction. Radial channels may be communicated with central channel over restriction as hollow rod slides upwards. Springing ring is adapted for adjustable hollow rod fixation as hollow rod slides downwards.

EFFECT: increased simplicity, reliability and manufacturability.

3 cl, 2 dwg

Description

The invention relates to the oil and gas industry, and in particular to devices for tight separation of the well during operation, cleaning and processing of the discovered reservoir.

The well-known "Packer" (RF patent No. 2209295, IPC ЕВВ 33/12, publ. 07/27/2003), comprising a housing with sealing elements and radial holes above and below the sealing elements, a hollow barrel forming an annular space with the housing connected to external space, a spring-loaded sleeve having the possibility of axial movement, and slips, while the spring-loaded sleeve is made in the form of a hollow cylinder, the outer surface interacting with the inner surface of the housing and forming an annular gap between the outer surface Tew stem and the inner surface of the spring-loaded sleeve, on the inner end of the spring-loaded sleeve made planting band and the inner surface of the spring loaded sleeve has a groove, wherein the lower radial holes placed at the bottom of the annular space, and the upper radial openings are arranged to be overlapping spring sleeve.

The disadvantages of this device are:

firstly, the complexity of manufacturing due to the presence of a large number of hermetically moving parts that require accurate and high-quality manufacturing;

secondly, unauthorized installation of the packer is possible, since the response depends on the pressure drop that may occur when lowering into the well as a result of water hammer;

thirdly, communication between the overpacker and underpacker spaces may occur as a result of the weakening of the spring and the spring-loaded sleeve as a result of corrosion, since they are constantly under the action inside the borehole medium.

The closest in technical essence and the achieved result is a "Device for cleaning and maintaining the productivity of the reservoir" (RF patent No. 2252308, IPC ЕВВ 37/00, publ. Bull. No. 14 dated 05/20/2005), containing a downhole cutter, including a housing , a check valve and a packer, consisting of a cuff and an expanding cone connected to the housing by shear elements, and a landing tool including a hollow stem, muffled from below, with radial channels above the plug and the lower end mounted telescopically in the expanding cone, while it is sn It is equipped with a slip unit, the landing tool is equipped with upper and lower bodies, the lower body being mounted telescopically on the hollow stem and connected to the upper part of the expanding cone by shear elements, in the outer groove made in the lower body, a self-sealing sleeve is located around the perimeter, the upper body is connected by a hollow stem with a string of tubing of limited volume, a self-sealing spacer with longitudinal grooves is rigidly mounted on the upper case, a tubing string of limited through the clutch is connected to the cylinder of the relief valve, and the stepped rod of the latter is equipped with upper and lower stops and is connected with the said cylinder by shear elements, while the slip-type assembly includes a pipe with a figured groove on the outer surface connected to the lower end of the body of the downhole cutter, a movable sleeve, mounted on the nozzle, a finger fixed at one end to the movable sleeve, and the other included in the aforementioned figured groove, and a spring centralizer, rigidly connected to the movable sleeve, at the upper ends x which has slips that interact with a cone sample made at the lower end of the bottomhole cutter body.

The disadvantages of this device are:

firstly, the impossibility of pumping process fluids into the under-packer space;

secondly, a complex landing tool;

thirdly, it is possible to move the device upward with an overpressure from below (especially relevant for high-pressure and high-productivity well formations).

The technical task of the invention is the creation of a simple, reliable and technological design of the packer due to reliable mechanical fixation in the required interval of the well, carrying out various technological operations, including those with the reservoir off.

The technical problem is solved by a packer comprising a housing with a central channel, a nozzle having a figured groove on the outer surface, and a cone selection adjacent to the nozzle, a movable sleeve mounted on the nozzle, with a finger interacting with the figured groove, and a spring-loaded centralizer, at the ends of which there are slips that interact with the cone sample, the upper self-sealing and lower cuffs, a check valve, a landing tool, rigidly connected to the tubing string (tubing) and the body catfish with shear elements, a hollow plugged rod with radial channels, mounted telescopically in the central channel of the housing.

What is new is that the landing tool is made in the form of a nozzle with an emphasis on the inner surface, the inner cavity of which is in communication with its outer space, and the conical selection of the body is made in the form of upper and lower cones, between which the nozzle is located, and above the upper cone and below the lower the cone, respectively, are located the upper self-sealing cuff and the lower cuff, made in the form of a self-sealing cuff of the opposite direction of the upper, while the centralizer is made in the form of upper and the lower centering elements provided with corresponding multidirectional slips, the central channel is provided with a narrowing from the bottom, into which, with the possibility of limited axial movement, a rod is plugged, which is damped above the radial channels, above which a spring ring and a seal are installed sequentially from the bottom upwards, and the radial channels are made with the possibility of communication with the Central channel above the narrowing when moving the rod up, and the spring ring is made with the possibility of adjustable fixation rod when moving downwards.

Also new is the fact that the body above the upper self-sealing cuff is made with the possibility of adjustment in length.

Also new is that the figured groove is made in the form of two short and one long, installed between short, longitudinal grooves, sequentially interconnected by figured grooves, one of which connects the bottom of the first of the short grooves, which is transport, with the middle of the long longitudinal groove, which is a worker, and the other is the bottom of a long groove with the middle of another short longitudinal groove, which is removable and located along the length in the region of the middle of a long groove.

Figure 1 shows the packer in axial section.

Figure 2 shows a curly groove in the expanded state.

The packer consists of a housing 1 (see Fig. 1) with a central channel 2, a pipe 3 having a shaped groove 4 on the outer surface, and a cone selection consisting of upper 5 and lower cones 6 adjacent to the pipe 3, a movable sleeve 7 installed on the pipe 3, with a finger 8, interacting with a figured groove 4, and a centralizer spring-loaded by means of springs 9, consisting of an upper 10 and a lower 11 centering elements, at the ends of which there are corresponding multidirectional slips 12 and 13, interacting with the corresponding cones 5 and 6 to onus sampling, the upper 14 and lower 15 self-sealing multidirectional cuffs, the landing tool 16 connected rigidly to the string of tubing (tubing) (not shown in Fig.1, 2) and the housing 1 by shear elements 17, rod 18 with radial channels 19 mounted telescopically in the central channel 2 of the housing 1. The rod 18 above the radial channels 19 is muffled by a plug 20.

The landing tool 16 is made in the form of a pipe with a stop 21 on the inner surface, the inner cavity of which is in communication with its outer space through the holes 22. Upper 14 and lower 15 self-sealing cuffs are respectively located above the upper cone 5 and below the lower cone 6.

The central channel 2 of the housing 1 is provided with a restriction 23 from below, into which the aforementioned rod 18 is inserted with limited axial movement. The rod 18 above the radial channels 19 is provided with ring samples 24 and 25, in which a spring ring 26 and a seal 27 are installed respectively.

The radial channels 19 of the rod 18 are arranged to communicate with the central channel 2 of the housing 1 above the narrowing 23 when the rod 18 is moved up.

The spring ring 26 is made split with the possibility of adjustable fixation of the rod 18 in the Central channel 2 relative to the housing 1 when moving the rod 18 down. During the assembly of the packer, the selection of the spring ring 26 (according to the inner and outer diameters, as well as the physicomechanical properties and the grade of steel) controls the gap between the spring ring 26 and the ring selection 24 of the rod 18.

The axial movement of the rod 18 in the Central channel 2 relative to the housing 1 is limited by the upper 28 and lower 29 ring stops.

Figured groove 4 (see Figure 2) can be made in the form of two longitudinal short 30, 31 and one longitudinal long 32, installed between short 30 and 31 longitudinal grooves, connected in series by curly grooves 33 and 34, one of which 33 connects the bottom of the first of the short grooves 30, which is transport, with the middle of the long longitudinal groove 32, which is the working one, and the other 34, the bottom of the long groove 32, with the middle of another short longitudinal groove 31, which is removable and located along the length in the region of the middle of the long groove odolnogo groove 32. The housing 1 above the upper self-sealing cuff 14 (sm.Fig.1) can be made adjustable in length by means of additional pipes 35.

The device operates as follows.

Before lowering the packer into the well, if necessary, the length of the casing 1 is adjusted using additional nozzles 29 (see Fig. 1). The rod 18 is located in the Central channel 2 relative to the housing 1 in the upper position, in which the spring ring 26 is placed on the upper edge of the narrowing 23 in the expanded state.

The packer assembly with the landing tool 16 by means of shear elements 17 is attached to the tubing string and lowered into the well (not shown in Figs. 1 and 2), while pin 8 (see Fig. 1) is located in the first short longitudinal groove 30 of the figured groove 4 (see Figure 2) - transport position, not allowing the slips 12 and 13 to interact with the cones 5 and 6 of the cone sample, and the centering elements 10 and 11 of the spring centralizer, pressed outward by the springs 9, interact with the walls of the well. During the descent, the borehole fluid does not inflate the lower self-sealing cuff 15, since the rod 18 relative to the housing 1 is in the upper position (see Figure 1), in connection with which the borehole fluid, acting from below on the plug 20 of the rod 18, raises the latter and flows from the bottom up through the radial channels 19 of the rod 18, through the narrowing 23 into the central channel 2 of the housing 1 and then through the holes 22 of the landing tool 16 into the outer space (not shown in Figs. 1 and 2). The maximum axial movement of the rod 18 upward in the central channel 2 relative to the housing 1 in the upper position of the rod 18 is limited by its lower ring stop 29.

Upon reaching the installation interval of the packer located in the well, located above the opened formation (not shown in Figs. 1, 2), descent is stopped. Then the tubing string is lifted with the housing 1 (see FIG. 1) to a length greater than the length of the first short longitudinal groove 30 (see FIG. 2), and turned clockwise to a length greater than the length of the figured groove 33. As a result, finger 8 moves from the first short longitudinal groove 30 along the curly groove 33 to the long longitudinal groove 32 — the working position, since the centering elements 10 (see FIG. 1) and 11, interacting with the walls of the well, hold the movable sleeve 7 with finger 8 in place.

After which the tubing string is unloaded, the housing 1 (see Figure 1) moves down, and the movable sleeve 7 remains in place. As a result, the upper slips 12, interacting with the upper cone 5, are pressed against the walls of the well, fixing the housing 1 relative to the well, and the shear elements 17 are destroyed, freeing the housing 1 from the planting tool 16, which rests on its upper edge 21 on the upper edge of the housing 1 or on an additional pipe 35 (depending on the design of the additional pipe 35 - in Fig. 1, the stop 21 will rest on the additional pipe 35).

Next, the tubing string together with the planting tool 16 is removed from the well, after which the submersible pump (not shown in FIGS. 1, 2) is lowered on the tubing string, or is lifted if the tubing string is equipped immediately with a submersible pump. Then start the submersible pump, under the action of which the opened formation is cleaned and operated. In this case, the production of the reservoir under the action of a submersible pump and along the tubing string is removed from the well. This is because the rod 18 in the central channel 2 relative to the housing 1 is in the upper position (see Fig. 1) and the production of the layer, acting from below on the plug 20 of the rod 18, lifts the latter and flows from the bottom up through the radial channels 19 of the rod 18 through narrowing 23 into the central channel 2 of the housing 1 and rises above the packer, falling on reception of the aforementioned submersible pump. If the performance of the submersible pump exceeds the productivity of the formation, then the liquid level above the packer decreases, reducing the pressure acting on the upper self-sealing cuff 14, and the pressure acting on the lower self-sealing cuff 15 remains constant, as it is due to reservoir pressure. Under the action of a pressure differential acting on the lower self-sealing cuff 15, the housing 1 moves upward until the lower slips 13 interact with the lower cone 6, since the movable sleeve 7 is fixed by the upper 10 and lower 11 centering elements of the spring centralizer relative to the borehole walls and can freely move up and down by pipe 3. As a result, the housing 1 is rigidly fixed relative to the walls of the borehole with the lower slips 6, and multidirectional self-sealing cuffs 14 and 15 reliably separate the inner space consistency of the well. In this case, the operation of the formation by the submersible pump does not stop. If it is necessary to temporarily isolate (shut off) the formation (for example, to replace a submersible pump), the well is filled with liquid and excessive pressure is created on top of the packer, by which, on the upper self-sealing sleeve 14, the housing 1 moves downward until the upper slips 12 interact with the upper cone 5, fixing the housing 1 relative to the walls of the well. The overpressure from above also acts on the rod 18, the position of which in the central channel 2 relative to the housing 1 is controlled by the gap between the spring ring 26 and the ring selection 24 of the rod 18. Upon reaching a certain excess pressure on the rod 18, the spring ring 26 interacting with the upper edge of the narrowing 23 in the upper position of the rod 18 in the Central channel 2 relative to the housing 1 (see Figure 1), is compressed inside the annular selection 24 of the rod 18. In this case, the rod 18 under the action of the above overpressure moves down h relative to the housing 1, and the spring ring 26 in a compressed state slides along the inner surface of the narrowing 23. The downward movement of the rod 18 continues until the spring ring 26 comes out of the narrowing 23 and unclenched in the Central channel 2 of the housing 1, while the seal 27 and the plug 20 of the rod 18 will also move down, and the upper annular stop 28 of the rod 18 will abut against the upper edge of the narrowing 23. As a result, the seal 27 seals the central channel 2 of the housing 1, and the rod 18 in the central channel 2 occupies a lower position relative to Pusa 1, wherein the inner cavity is well sealed uncoupling. To resume the operation of the reservoir, the central channel 2 of housing 1 is depressurized. For this, the liquid level above the packer is reduced using a pump previously lowered into the well, thereby reducing the pressure acting on the upper self-sealing cuff 14. Moreover, the pressure acting on the lower self-sealing cuff 15 remains constant, as it is due to reservoir pressure. Under the action of the differential pressure acting on the lower self-sealing cuff 15, the housing 1 moves upward until the lower slips 13 interact with the lower cone 6, which fix the housing 1 relative to the borehole walls.

Upon reaching a certain pressure difference on the plug 20 of the rod 18 from the bottom, which is regulated by the gap between the spring ring 26 and the ring selection 24 of the rod 18, the spring ring 26, which interacts with the lower edge of the restriction 23 due to the above pressure drop, is compressed and enters the restriction 23. When this rod 18 and placed in its annular selection 24 of the spring ring 26 in a compressed state move upward relative to the housing 1 on the inner surface of the narrowing 23. The upward movement of the rod 18 upwards continues until the spring to The ring 26 will not come out of the restriction 23 and will not be squeezed in the central channel 2 of the housing 1, while the plug 20 and the seal 27 of the rod 18 will also move up. As a result, the rod 18 again occupies an upper position relative to the housing 1, as described above, depressurizing the Central channel 2 of the housing 1 and communicating the internal cavity of the well. Then the operation of the wellbore is carried out in the usual mode.

If it is necessary to remove the packer from the well, a tubing string is lowered into it with a tube at the lower end, which captures the packer body 1. Then the tubing string is lifted with the housing 1 to a length greater than the length of the long longitudinal groove 32 (see FIG. 2) and rotated clockwise to a length greater than the length of the horizontal part of the curly groove 34. After that (see FIG. 1) the tubing string with the housing 1 is lowered to a length greater than the length of the long longitudinal groove 32 (see Figure 2), and then raised again. As a result, the finger 8 moves from the long longitudinal groove 32 along the curly groove 34 to another short longitudinal groove 31 — the position for removing the packer, since the slips 12 (see FIG. 1) and 13 cannot interact with the corresponding cones 5 and 6. Next the packer assembly is removed from the well.

The design of the proposed packer is simple, reliable and technologically advanced due to its mechanical reliable fixation in the required interval of the well and the possibility of various technological operations, including those with the reservoir off.

Claims (3)

1. A packer comprising a housing with a central channel, a nozzle having a figured groove on the outer surface, and a cone selection adjacent to the pipe, a movable sleeve mounted on the pipe, with a finger interacting with the figured groove, and a spring-loaded centralizer, at the ends of which are located the slips interacting with the cone selection, the upper self-sealing and lower cuffs, the check valve, the landing tool, connected rigidly to the tubing string and tubing with shear elements, a hollow end a stock rod with radial channels mounted telescopically in the central channel of the housing, characterized in that the landing tool is made in the form of a pipe with a stop on the inner surface, the inner cavity of which is in communication with its outer space, and the conical selection of the body is made in the form of upper and lower cones, between which there is a nozzle, with the upper self-sealing cuff and the lower cuff made in the form of self-sealing, respectively, located on top of the upper cone and below the lower cone cuff, opposite the upper one, while the centralizer is made in the form of upper and lower centering elements provided with corresponding multidirectional slips, the central channel is provided with a narrowing from the bottom, into which, with the possibility of limited axial movement, a rod is inserted that is muffled above the radial channels, above which are sequentially from the bottom up spring ring and seal are installed in the ring samples, and the radial channels are arranged to communicate with the central channel above the narrowing when moving the rod up, and the spring ring is made with the possibility of adjustable fixation of the rod when moving it down. 2. The packer according to claim 1, characterized in that the housing above the self-sealing cuff is made with the possibility of adjustment along the length. 3. The packer according to claim 2, characterized in that the figured groove is made in the form of two short and one long, installed between short, longitudinal grooves, sequentially interconnected by figured grooves, one of which connects the bottom of the first of the short grooves, which is transport, with the middle of the long longitudinal groove, which is the working one, and the other, the bottom of the long groove with the middle of another short longitudinal groove, which is removable and located along the length in the middle of the long groove.

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