RU2509872C1 - Well formation treatment device - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: well formation treatment device includes a packer. The packer includes a flow-through housing in an axial direction, the outer surface of which is provided with a shaped slot, a yoke with a pin and slips and an elastic cuff. The pin is installed into the shaped slot and has the possibility of being moved along the shaped slot trajectory. The slot is made in the form of transverse and longitudinal grooves located perpendicular to each other and connected to each other in the lower part of the longitudinal groove. The device includes a disconnector. The disconnector includes a shaft with upper and lower threads and a spool located inside the shaft. The spool and the shaft are connected with shear elements. The spool is equipped with an axial central hole and a bore, in which a retaining ring interacting with the annular groove and a seat for a shutoff element is installed. The bore is made on the inner surface of the spool. A lower ring that is made in the form of a cover plate is screwed on the lower shaft thread. The cover plate is equipped from below with external thread for connection to the packer housing, and the cover plate is equipped in its centre with a bar rigidly fixed on it and axial holes in a circumferential hole. The bar is directed towards the spool and has the possibility of tight interaction with the axial central hole of the spool. Carrying capacity of the holes of the cover plate is higher than that of the central spool hole. An annular groove having the possibility of interacting with the retaining ring is made in the form of annular notches on the outer surface of the bar. The shutoff element is made in the form of a semi-sphere rigidly attached from above to a stock equipped with sealing discs.

EFFECT: possibility of performing interval-by-interval treatment of formations in a horizontal well; increasing durability and reliability of the device operation; enlarged technological capabilities of operation.

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Description

The invention relates to the oil and gas industry, and in particular to devices for separating formations in a well with separate injection of various reagents.

A device for treating formations in a well is known (patent RU No. 2282017, IPC ЕВВ 33/12, published in Bulletin No. 23 of 08/20/2006), containing a packer including a passage housing and an elastic sleeve, an isolator including a trunk with radial channels and internal cylindrical sampling, a spool with two rows of radial channels separated by a transverse blind partition, and a sleeve with a seating seat for a ball discharged into the device before processing the second layer inserted inside the spool, the upper row of radial of the spool channels is opposite the radial channels of the barrel, and the barrel, spool and sleeve are interconnected by differential shear elements, and before processing the second layer, the upper and lower rows of radial channels of the spool communicate with each other through an internal cylindrical barrel sampling, hydraulically connecting the inner space of the tubing pipes (tubing) with the internal space of the packer body, while the device is higher than the disconnector at a distance from the packer exceeding the thickness of the upper about the reservoir, is equipped with an additional packer consisting of a cylinder on top and an additional elastic cuff mounted on a floor connected to the disconnector by means of a coupling, to which the piston is rigidly connected at the top, and a cylinder rigidly connected to the tubing string, into which the piston is telescopically mounted the possibility of axial movement upward, forming with the piston a cavity hydraulically connected to the interior of the tubing, and the cylinder is configured to Interaction of a more elastic cuff.

The disadvantages of this device are:

- firstly, the complexity of the design, due to the presence of a large number of nodes and parts;

- secondly, the complexity and high cost of manufacturing both the device itself and the grooves on the outer surface of the packer passage housing;

- thirdly, the limited annular space of the disconnector between the barrel and the spool, and therefore it is impossible to pump a highly viscous chemical composition through this annular space.

Also known is a device for treating formations in a well (patent RU No. 2282710, IPC ЕВВ 33/12, published in Bulletin No. 24 of 08/27/2006), comprising a packer including a through-case and an elastic sleeve, an isolator including a barrel with radial channels and internal cylindrical sampling, a spool inserted into the barrel with two rows of radial channels separated by a transverse blind partition, a sleeve installed inside the spool with a seat for the ball that is discharged into the device before processing the second layer, while the top row is glad ial channels of the spool are opposite the radial channels of the barrel, and the barrel, spool and sleeve are interconnected by differential shear elements, and before processing the second layer, the upper and lower rows of radial channels of the spool communicate with each other through an internal cylindrical selection of the barrel, hydraulically connecting the inner space of the tubing pipes with the interior of the packer body, while the device is above the disconnector at a distance from the packer in excess of the thickness of the upper the reservoir is equipped with an additional packer consisting of an upper stop with a cylindrical constriction, a lower stop and an additional elastic cuff mounted on a cylindrical narrowing of the upper stop, which is telescopically mounted with the possibility of axial movement down to the lower stop, relative to which a shear element is fixed, while the lower stop made with the possibility of interaction with an additional elastic cuff, the upper stop is equipped with hydraulic anchors, drawn inward and interacting with the casing hydrochloric column under pressure produced in the interior of the tubing.

The disadvantages of this device are:

- firstly, the complexity of the design, due to the presence of a large number of nodes and parts;

- secondly, the complexity and high cost of manufacturing both the device itself and the grooves on the outer surface of the packer passage housing;

- thirdly, the limited annular space of the disconnector between the barrel and the spool, and therefore it is impossible to pump a highly viscous chemical composition through this annular space.

The closest in technical essence and the achieved result is a device for treating formations in a well (patent RU No. 2234589, IPC ЕВВ 33/12, published in bulletin No. 23 dated 08/08/2004), containing a packer including a housing, a clip with with dowels and a pin, and the pin is installed in a figured groove and has the ability to move along the trajectory of the figured groove and an elastic cuff, a disconnector including a barrel and a spool equipped with radial channels, while the packer body is made through in the axial direction, and the disconnector spool is located outside its three trunks, connected with shear elements, is muffled from below and has a smaller diameter on the outer surface above the muffled section, forming a cavity with a barrel communicating through radial channels with the internal space of the disconnector, equipped with a conical bore in which a retaining ring is installed, interacting with the annular a groove located in the lower part of the barrel and a saddle for a locking element, made in the form of a ball, discharged into the device before processing the second layer.

The design disadvantages of this device, which are identified on the basis of experience in its practical application for 8 years, are:

- firstly, it does not allow for interval processing of formations in a horizontal well, since the shut-off element, made in the form of a ball, discharged from the wellhead, does not sit on the spool seat, therefore it is impossible to disconnect the horizontal well formation that is lower than the wellhead and process the overlying relative to the wellhead of a horizontal well formation;

- secondly, it does not allow the processing of formations using viscous chemical compositions such as gel, water-swelling polymer (GNP), etc., this is due to such a design flaw as the small annular space of the disconnector between the barrel and the spool, therefore this annular space is clogged with a highly viscous chemical composition and is not further pressed through, in connection with which the device does not further fulfill its functions, which narrows the technological capabilities of the device;

- thirdly, two threads are made at the lower end of the disconnector barrel: the first is on the outside, into which the upper support of the packer is screwed, and the second thread is made from the inside of the barrel and the lower ring is screwed into it, so the lower part of the barrel is the place of concentration of tensile-compression stress and as shown by practical experience, the thread between the upper support of the packer and the disconnector barrel is extended (the gauge does not wrap) after a maximum of five tripping operations of the device, after which the disconnector barrel needs to be replaced, therefore, significantly o reduced durability of the device;

- fourthly, the low reliability of the device due to the fact that during the descent of the device into the well and during the processing of the lower layer, it is possible to deposit dirt, precipitation in the annular space between the spool and the disconnector barrel, as a result of which, when the spool is subsequently moved relative to the barrel, the ring may not be fixed in the annular groove of the disconnector barrel, since it is too low. As a result, it is impossible to hermetically cut off the lower layer and work with the upper layer;

- fifthly, a large number of grooves are made on the outside of the packer body around the entire perimeter, which leads to an increase in the cost of manufacturing this device.

The objectives of the invention are to develop a device design that allows for interval processing of formations in a horizontal well and expanding the technological capabilities of the device, as well as increasing the durability, reliability of the device, as well as reducing the cost of its manufacture.

The problem is solved by a device for treating formations in a well, comprising a packer, including an axially extending body with a figured groove on the outer surface, a clip with a pin and slips, the pin being installed in a figured groove and being able to move along the path of the figured groove, and an elastic cuff , a disconnector, including a barrel with upper and lower threads, and a spool located inside the barrel and connected to it by shear elements, the spool is provided with a bore in which the retaining ring is installed o, interacting with an annular groove located in the lower part of the barrel and a saddle for a locking element discharged inside the device before processing the second layer, and a lower ring screwed onto the lower thread of the barrel.

New is that the figured groove on the outer surface of the packer through passage is made in the form of transverse and longitudinal grooves located perpendicular to each other and connected to each other in the lower part of the longitudinal groove, and the spool of the disconnector is provided with an axial central hole from the bottom, while the bore which the retaining ring is installed on is made on the inner surface of the spool, and the lower ring is made in the form of a cap screwed onto the lower thread of the disconnector barrel, and the bottom is provided with a cap with a threaded thread for connection with the body of the feedthrough packer, and in the center the cover is equipped with a rigidly fixed rod thereon directed towards the spool, as well as axial holes around the circumference, while the throughput of the cover openings is greater than the throughput of the central hole of the spool, and the rod has the ability to tightly interact with the axial central hole of the spool, after the locking element is planted on the spool seat and the axial movement of the spool relative to the disconnector barrel, m circular groove having the opportunity to interact with the locking ring, formed on the outer surface of the rod in the form of annular notches directed opposite to the retaining ring, wherein the locking element is in the form of a hemisphere, zhestkozakreplennoy top with the rod fitted with sealing disks.

Figure 1 shows the lower part of the proposed device in longitudinal section.

Figure 2 - scan of the shape and direction of the curly groove of the packer body.

Figure 3 shows the upper part of the proposed device in longitudinal section.

Figure 4 shows the spool in the lower position fixed relative to the barrel.

The device consists of a packer and disconnector.

The packer comprises an axially-extending housing 1 (FIG. 1) with a figured groove 2 on the outer surface (FIG. 1). Figured groove 2 (figure 2) on the outer surface of the passageway of the packer 1 is made in the form of longitudinal 3 and transverse 3 'grooves located perpendicular to each other and interconnected in the lower part of the longitudinal groove 3, therefore, the number of grooves is reduced in comparison with the prototype figured groove and, as a result, the manufacturing cost of the device is reduced.

On the housing 1 (Fig. 1), with the possibility of axial movement, a cage 4 is mounted, connected at the bottom with a ring 5 connected to a guide pin 6 located in the transverse groove 3 'of the figured groove 2. In the upper part of the cage 4, spring-loaded slips 7 with a locking element are installed 7 '. On the housing 1 above the slips 7 there is a lower support 8, an elastic sleeve 9 and an upper support 10, rigidly connected to the housing 1 of the packer. The length of the transverse groove 3 'of the figured groove 2 corresponds to the scan length of the passage housing 1 at an angle of 180 °. The length of the longitudinal groove 3 corresponds to the height of the displacement of the tubing string (tubing) 10 (see figure 3) during the round-trip operations plus 0.5 meters.

With the upper support 11 (see Fig. 1) of the packer, a disconnector barrel 12 (see Fig. 3) is connected, provided with radial channels 13. Inside the barrel 12, opposite the radial channels 13, a spool 14 is mounted connected to the barrel by shear elements 15.

Below, the spool 14 of the disconnector is provided with an axial central hole 16, while the bore 17, in which the retaining ring 18 is installed, is made on the inner surface of the spool 14. The lower ring is made in the form of a cover 19, screwed onto the lower thread 20 of the barrel 12 of the disconnector. The bottom cover 19 is provided with an external thread 21 (figure 1) for connection with the passage housing 1 of the packer.

The durability of the proposed device increases, since the threads are spaced along the height of the lower ring, made in the form of a cover.

In the center, the cover 19 (Fig. 3) is provided with a rod 22 rigidly fixed on it, directed towards the spool 13, as well as axial holes 23 around the circumference.

The number of holes 23 is chosen so that the throughput (Q ₁ ) of the holes 23 is greater than the throughput (Q ₂ ) of the central hole 16 of the spool 14 (Q ₁ > Q ₂ ), which allows the injection of viscous chemicals. The throughput (Q ₂ ) of the Central hole 16 of the spool 14 is determined by the size of its cross section (diameter of the bore), which is determined empirically based on the estimated viscosity of the injected chemical reagent.

In comparison with the prototype, by eliminating the annular space between the spool and the disconnector barrel from the device design, the device's throughput increases, and it allows both processing and cleaning of one or several formation intervals with acid compositions of various viscosities in one run.

The rod 22 has the ability to tightly interact with the axial Central hole 16 of the spool 14, after landing the locking element 24 on the seat saddle 17 of the spool 14 and the axial movement of the spool 14 down relative to the barrel 12 of the disconnector. An annular groove interacting with the retaining ring 18 is made on the outer surface of the shaft 22 in the form of annular notches 25 in the opposite direction to the retaining ring 18 (see Fig. 4), which ensures reliable fixation of the spool relative to the disconnector barrel.

The locking element 24 is made in the form of a hemisphere 25, rigidly mounted on top with a rod 26, equipped with sealing discs 27, for example two, as shown in figure 3. The hemisphere 25 and the rod can be made as a whole part, as shown in figure 3. Sealing discs 27 made in the form of flat rubber elements having the ability to tightly interact with the inner surfaces of the tubing string 10 and the spool 14 and when moving the locking element down to interact with the seat 28 of the spool 14 under the influence of excess hydraulic pressure above the shut-off element 24.

In order to exclude unauthorized fluid flows, the mating surfaces of the spool 14 (see Fig. 3) are provided with sealing elements (not shown in Figs. 1-4).

The device operates as follows.

A device for treating formations in wells, including those with inclined and horizontal shafts, allows for the injection of various chemicals (acids, hydrocarbon solvents) of various viscosities in order to increase production capabilities of production wells and increase the injectivity of injection wells by improving the filtration characteristics of the bottom hole in the result of physico-chemical effects. The device is assembled on the tubing string 10 (figure 3) is lowered to the required depth in a horizontal well for processing formations in the well, i.e. interval treatment of the formation with various chemicals, for example, acid compositions of various viscosities.

For example, for injecting a viscous thickened acid composition into a nearby horizontal well (lower) to the bottom of the well bottom and hydrochloric acid treatment of a nearby (upper) horizontal well to the wellhead. Place the device between the layers in a horizontal well, which must be treated with acid compositions of various viscosities. Then the packer is planted; for this, the device is first turned clockwise through an angle of 180 °, and then lowered by 1.0 m.

As a result of this, the pin 6 (FIG. 2) from the transverse groove 3 'of the figured groove 2 is moved to the longitudinal groove 3 (before the device is lowered into the well, the pin 6 is installed in the far left lower part of the transverse groove 3' of the figured groove 2 (as shown in FIG. 2). The tubing string 10 (Fig. 3) is lowered down, while the parts 4, 5, 6, 7, 7 '(see Fig. 1) remain in place, since the springs 29 press the smooth part of the slips 7 to the walls of the casing (not shown), and parts 1, 8, 9, 10 and parts of the disconnector move down until the conical part of the lower support 8 abuts against ipsy 7. Under the weight of the tubing slips 7 diverge radially to contact the tooth portion of the casing, and the elastic sleeve 9 is compressed under load, securely closing the annulus of the well.

After that, they begin processing the lower layer of the horizontal well. To do this, viscous thickened acid composition through tubing 26 through the central hole 16 (Fig. 3) of the spool 14, the axial holes 23 of the cover 19 and the inner space 30 (Fig. 1) of the packer housing 1 are pumped and forced into the horizontal horizontal interval of the reservoir wells and left to react.

Then proceed to the treatment of the horizontal well overlying the wellhead relative to the wellhead. To do this, inward the tubing 10 (Fig. 3) throw the locking element 24 with the hemisphere 25 down and create in the tubing string 10 above the locking element 24 excessive hydraulic pressure, for example 3 MPa, which leads to the hermetic movement of the locking element 24 along the tubing string in a horizontal well the sealing discs 27, interacting with the inner surfaces of the tubing string 10 and the spool 14. A sharp increase in overpressure in the tubing string 10 indicates that the hemisphere 25 of the locking element 24 has interacted with the seat 28 alotnik 14, i.e. the locking element sits on the seat 28 and overlaps the Central hole 16 of the valve 14.

In the tubing string, pressure is increased, as a result of which, under pressure, for example 6 MPa, the shear elements 15 are destroyed, the spool 14 moves downward relative to the disconnector barrel 12. The retaining ring 17 (see Fig. 4) enters the annular notches 25 of the rod 22 and moves down them until the lower end 31 of the spool 14 interacts (see Fig. 3) with the cover 19 and is fixed in the lower position (see Fig. 4 ), while opening the radial channels 13.

After that, through the tubing string 10 (see Fig. 3), through the radial channels 13 of the disconnector bore 12, a reagent is injected - 15% hydrochloric acid solution (15% HCL) into the upper layer of a horizontal well and allowed to react.

After exposure, swabbing is performed by lowering the level, while the movement of the spool 14 relative to the barrel 12 of the isolator is eliminated by fixing the retaining ring 18 in the annular notches 25 of the rod 22 of the isolator.

After processing the horizontal interval of the formation overlying the wellhead of the wellhead, the tubing string 10 is raised 1.0 m and turned counterclockwise through an angle of 180 °, while the packer body 1 also rises, the lower support 8 (see Fig. 1) comes out from engagement with the slips 7, the load on the elastic cuff 9 is removed, and it takes its original position, and the device receives the transport position and can be transferred to another interval of the well or raised to the surface.

The proposed device allows for interval processing of formations in a horizontal well, as it ensures that the locking element is planted on the valve seat, increases the durability and reliability of the device, has advanced technological capabilities, while reducing the cost of manufacturing the device.

Claims (1)

A device for treating formations in a well, comprising a packer, including an axially extending body with a figured groove on the outer surface, a clip with a pin and slips, the pin being installed in a figured groove and having the ability to move along the path of the figured groove, and an elastic cuff, disconnector, including a barrel with upper and lower threads, and a spool located inside the barrel and connected to it by shear elements, the spool is equipped with a bore in which a retaining ring is installed, interacting with the rings the first groove located in the lower part of the barrel and the saddle for the locking element that is discharged inside the device before processing the upper layer, and the lower ring screwed onto the lower thread of the barrel, characterized in that the figured groove on the outer surface of the bushing of the packer is made in the form of a transverse and longitudinal grooves located perpendicular to each other and interconnected in the lower part of the longitudinal groove, the bottom of the spool disconnector provided with an axial central hole, with a bore in An open snap ring is installed, made on the inner surface of the spool, and the lower ring is made in the form of a cover screwed onto the lower thread of the disconnector barrel, the bottom of the cover being provided with an external thread for connection with the body of the through packer, and the center of the cover is equipped with a rigidly fixed rod directed at it towards the spool, as well as axial holes around the circumference, while the throughput of the cover holes is greater than the throughput of the central hole of the spool, and the shaft has the tightness of the interaction with the axial Central hole of the spool, after landing the locking element on the seat of the spool and the axial movement of the spool relative to the stem of the uncoupler, and the annular groove having the ability to interact with the retainer ring is made on the outer surface of the rod in the form of annular notches directed opposite to the retainer ring, while the locking element is made in the form of a hemisphere, rigidly fixed on top with a rod equipped with sealing discs.

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