RU60603U1 - Casing Repair Tool - Google Patents

Abstract

The proposal relates to the oil industry and can be used in the repair of casing strings in wells with two or more violations. A device for repairing a casing string in a well comprises a casing string and a sealing plug in the form of a hollow, elastically deformed body with the possibility of exceeding the inner diameter of the casing string. The elastic-deformed body is reinforced from the inside with a metal cup, which is fixed on the bottom of the casing. The inner diameter of the metal cup is smaller than the inner diameter D _{1 of the} casing in the transport position (D ₂ <D ₁ ). Inside the casing string above the metal cup on the pipe string is a piston with a cylinder. The bottom of the cylinder is equipped with a cone, which, in turn, is equipped on the outer surface with an expanding cone, prefabricated in diameter from dies, which are spring loaded from the top of the cylinder by means of a spring and a sleeve. The sleeve is located above the dies and is located on the outer cylindrical selection of the cone, and provides limited movement of the dice up the cone. The dice are connected to an expanding cone by a dovetail connection. The dies are made with the possibility of pressing an elastically deformed body with a metal cup to the casing and with a base diameter smaller than the inner diameter D _{4 of the} metal cup in its working position (D ₃ <D ₄ ). The device is equipped with an anchor assembly installed above the cylinder and consisting of a hollow rod, a wedge pusher, dies and a hollow stop. The wedge pusher is rigidly mounted on a hollow rod, which is rigidly connected to the cylinder piston, and with a hollow stop - telescopically hermetically with the possibility of axial upward movement. The dies of the anchor assembly are placed on the hollow stem and are connected to the lower end of the hollow stop, for example, by a “T-shaped" connection with the possibility of radial movement outward when interacting with a wedge pusher. The hollow stop is equipped on the outside with a self-sealing cuff, which allows fluid to pass from bottom to top, while a load equipped with radial channels is screwed onto the hollow stop from above. The hollow rod above the wedge pusher is equipped with through holes that allow liquid to pass from the bottom up during the descent of the device into

well. The device descends into the well on the cable, while the piston cavity of the cylinder is hydraulically connected to the interior of the casing above the self-sealing cuff. The sealing plug from below is connected by means of a nozzle to a second sealing plug of a similar design. The proposed device due to the fact that it is equipped with an anchor assembly is fixed in the casing of the well during the drilling of sealing plugs, and the improvement of the quality of repair of the casing of the well is achieved by sealing each violation of the casing individually, which allows to extend the life of the well until the next overhaul. In addition, the descent of the device on the cable can significantly reduce the duration of the repair, and therefore reduce the financial costs of well repair. 3 ill. for 1 liter

Description

The proposal relates to the oil industry and can be used in the repair of casing strings in wells with two or more violations.

A device for repairing a casing string in a well is known (copyright certificate SU No. 1768749 A1, IPC 7 E 21 B 33/13, publ. Bull. No. 38 of 10/15/1992), including a cementing plug with elastic cuffs, a sealing plug, tightly connected with the lower part of the cementing plug and made in the form of a hollow elastically deforming along the outer surface of the casing with the possibility of exceeding the diameter of the casing and a centering cone in the lower part of the casing, while ring grooves are made at the ends of the casing under the upper and lower parts of the casing.

The disadvantage of the device is that when the device is lowered into the well, the sealing plug may be damaged or torn, since it is in very close contact with the walls of the well, especially for old wells, where the walls have growths in the form of solid deposits. Leaky fit of the sealing plug leads to re-repair of the well.

The closest in technical essence is a device for repairing a casing string in a well (RF patent for utility model No. 52085, IPC 7 E 21 B 33/13, publ. Bull. No. 7 of 06/30/2005), containing a casing and sealing a plug in the form of a hollow elastically deformed body with the possibility of exceeding the diameter of the casing, while the elastically deformed body is reinforced from the inside with a metal cup, which is fixed on the bottom of the casing, and the inner diameter of the metal cup is smaller than the inner diameter the casing string is in transport position, while inside the casing pipe above the metal cup there is a piston with a cylinder on the pipe string, the piston cavity communicating with the pipe space of the pipe string, and the bottom of the cylinder is equipped with a cone equipped with an expanding cone made of a die-shaped assembly that spring-loaded from the top of the cylinder and made with the possibility of limited movement only along the cone up, and the dies are made with the possibility of pressing the elastically deforming body mustache with a metal cup to the casing

column and with a base diameter smaller than the inner diameter of the metal glass in its working position.

The disadvantages of this device are:

- firstly, during the refining of the sealing plug, the process of tension-compression of the pipe string occurs, since the latter is not fixed in the casing directly above the cylinder and therefore the reliability and quality of the sealing are reduced;

secondly, the sealing plug is installed only below the lower violation, which does not allow to seal each violation separately, and therefore the quality of repair of the casing string is reduced;

thirdly, the descent of the device on the pipe string increases the duration of the repair work as a whole.

The objective of the utility model is to fix the device in the casing of the well during the drilling of sealing plugs and to improve the quality of repair of the casing of the well by sealing each violation of the string separately, as well as reducing the duration of repair work by lowering the device into the well on the cable.

This problem is solved by the proposed device for repairing the casing string in the well, comprising a casing string and a sealing plug in the form of a hollow elastically deforming body with the possibility of exceeding the diameter of the casing string, while the resiliently deforming body is reinforced from the inside with a metal cup, which is fixed on the bottom of the casing, the inside diameter a metal cup is smaller than the inner diameter of the casing in the transport position, while inside the casing is higher than m There is a piston with a cylinder located on the bottom of the barrel, and the bottom of the cylinder is equipped with a cone equipped with an expanding cone, made prefabricated in diameter from the dies, which are spring-loaded from the top of the cylinder and configured to move only upward along the cone, and the dies are made with the possibility of pressing an elastically deformed body with a metal glass to the casing and with a base diameter smaller than the inner diameter of the metal glass in its working position.

New is that the device is equipped with an anchor assembly installed above the cylinder and consisting of a hollow rod, a wedge pusher, dies and a hollow stop, while the wedge pusher is rigidly mounted on the hollow rod, which is rigidly connected to the cylinder piston, and telescopically with the hollow stop hermetically sealed

the possibility of axial movement upward, and the dies of the anchor assembly are placed on the hollow stem and connected to the lower end of the hollow stop with the possibility of radial movement outward when interacting with the wedge pusher, the hollow stop is equipped on the outside with a self-sealing cuff, which allows fluid to pass from bottom to top, while cargo equipped with radial channels, and the hollow rod above the wedge pusher is equipped with through holes passing liquid from the bottom up during the descent of the device into the wells well, the apparatus being lowered into the well on a cable, with the subpiston cylinder chamber fluidly communicates with the interior of the casing above the self-sealing cuff.

Also new is that the number of sealing plugs is at least two, and they are interconnected by nozzles.

The figure 1 shows the proposed device for the repair of casing in the well in longitudinal section.

The figure 2 shows a longitudinal section of a well after repair.

The figure 3 shows a section aa of the expanding cone of the device.

A device for repairing a casing string (see FIG. 1) in a well comprises a casing string 1 and a sealing plug 2 in the form of a hollow, elastically deformed body 3 with the possibility of exceeding the inner diameter D _{1 of the} casing string 1.

The elastic deforming body 3 is internally reinforced with a metal sleeve 4, which is fixed on the bottom to the casing 1. The inner diameter D _{2 of the} metal sleeve 4 is smaller than the inner diameter D _{1 of the} casing 1 in the transport position (D ₂ <D ₁ ). A cylinder 5 with a piston 6 is located inside the casing 1 above the metal cup 4. The cylinder 5 is equipped with a technological hole 7 on top, which hydraulically communicates above the piston space 8 of the cylinder 5 with the outer space of the cylinder 5, which eliminates the effect of pistoning during operation of the device.

From the bottom, the cylinder 5 is equipped with a cone 9, which, in turn, is equipped with an expanding cone 10 on the outer surface, which is prefabricated in diameter from the dies 11, which are spring-loaded from the top of the cylinder 5 by means of a spring 12 and a sleeve 13. The sleeve 13 is located above the dies 11 and, being on the outer cylindrical sample 14 of the cone 9, provides a limited movement of the dies 11 up the cone. The dies 11 are connected to the cone 9 of the cylinder 5, for example, the dovetail connection (see figure 3). Dies 11 are made with the possibility

pressing the elastically deformed body 3 with the metal cup 4 to the casing 1 and with a base diameter D ₃ smaller than the inner diameter D _{4 of the} metal cup in its working position (D ₃ <D ₄ ) (see FIGS. 1 and 2).

The device is also equipped with an anchor assembly 15 installed above the cylinder 5 and consisting of a hollow rod 16, a wedge pusher 17 and dies 18 and a hollow stop 19.

The wedge pusher 17 is rigidly mounted on the hollow rod 16, which is rigidly connected to the piston 6 of the cylinder 5, and with a hollow stop 19 - telescopically with the possibility of axial movement up. The dies 18 of the anchor assembly 15 are placed on the hollow stem 16 and are connected to the lower end of the hollow stop 19 by a “T-shaped" connection with the possibility of radial movement outward when interacting with the wedge pusher 17. The hollow stop 19 is equipped on the outside with a self-sealing sleeve 20, which allows fluid to pass from bottom to top, at the same time, a load 21, equipped with radial channels 22, is screwed onto the hollow stop 19 from above.

The hollow rod 16 above the wedge pusher 17 is equipped with through holes 23, passing fluid from the bottom up during the descent of the device into the well.

The device descends into the borehole on cable 24, while the piston cavity 25 of cylinder 5 is hydraulically communicated through internal spaces: hollow rod 16, hollow stop 19, radial channels 22 of cargo 21 with inner space 26 of casing 1 above the self-sealing sleeve 20.

The sealing plug 2 from the bottom through the pipe 27 is connected to the second sealing plug 2 ', also made in the form of a hollow elastically deforming body 3' with the possibility of exceeding the inner diameter D _{1 of the} casing string 1.

The elastic deforming body 3 'is reinforced from the inside with a metal cup 4', the inner diameter D ₂ , which is smaller than the inner diameter D _{1 of the} casing 1 in the transport position (D ₂ <D ₁ ).

Unauthorized fluid flows into the device are prevented by O-rings 28, 29.

The device operates as follows.

Before the casing 1 is lowered (see FIG. 1) into the well, the sealing plugs 2 are assembled; 2 '; 2 "... 2 ⁿ , which are connected by nozzles 27; 27 '... 27 ⁿ , and the length of the nozzles 27 is selected so that each violation 30; 30' ... 30 ^{n of the} sealed pipe string 31 is higher than the corresponding sealing plugs 2; 2 '; 2 "... 2 ⁿ and sealed last.

On the lower end of the casing string 1, the assembled assembly of sealing plugs 2 is screwed; 2 '; 2 "... 2 ⁿ , for example, consisting of two sealing

plugs 2 and 2 '(see figure 1) The casing 1 is lowered into the well until each of the sealing plugs 2 and 2' is below the interval of violation 30; 30 'respectively of the pipe string 31 to be sealed in the well. After that, the upper part of the casing string 1 is attached to the wellhead (not shown in FIGS. 1, 2, 3) of the well.

Then, the proposed assembly is lowered into the casing 1 on cable 24 (see FIG. 1). During the descent of the device, the liquid located in the pipe string 31 is transferred from bottom to top through the through holes 23 into the hollow rod 16, and from there through the radial channels 22 of the cargo 21 into the inner space 26 of the casing 1 above the self-sealing sleeve 20.

The descent of the device on the cable 24 into the casing 1 of the well continues until the cylinder 5, connected by its cone 9 to the expansion cone 10, made by the dovetail connection assembly with a diameter of 11 of the dies, rests against the metal end 4 of the sealing plug 2.

At this moment, the upper part of the device, including the load 21, the hollow stop 19 with the self-sealing sleeve 20 located on its outer surface, the dies 18 will lower down relative to the hollow rod 16 until the dies 18 interact with the wedge pusher 17 of the anchor assembly 15, while the dies 18 are pulled out of the hollow stop 19 radially outward until its gear part interacts with the inner walls of the casing 1, and the through holes 23 of the hollow stem 16 are hermetically sealed by the sealing ring 29 of the hollow stop 19, as evidenced by comfort weight readings of the indicator (1, 2, 3 are not shown).

The device continues to be unloaded onto the sealing plug 2, while the dies 11 of the expanding cone 10, spring-loaded from the top of the cylinder 5 by means of the spring 12 and the sleeve 13, begin to move upward relative to the cone 9 of the cylinder 5 until the sleeve 13 located on the outer cylindrical sample 14 of the cone 9 does not reach its upper end, while the spring 12 is compressed, and the cylinder 5 remains stationary, and an increase in the readings by the amount of compression force of the spring 12 is observed on the weight indicator.

Then fill the casing 1 with the process fluid and seal it at the wellhead, after which the overpressure is created in the inner space of the casing 1 by means of a pumping unit (not shown in FIGS. 1, 2, 3), while the self-sealing sleeve 20 is pressed against the inside the walls of the casing 1, due to which, thanks to the radial channels 22 of the cargo 21, the same excess pressure is created in the under-piston space 25 of the cylinder 5, while the dies 18 of the anchor assembly 15 with its gear part are even stronger run into the inner walls of the casing 1, which eliminates the axial movement of the device

upwards and gives additional rigidity to the device when the sealing plugs 2 and 2 'are turned over.

The overpressure in the casing 1 and in the under-piston space 25 of the cylinder 5 continues to increase. As a result, the cylinder 5 begins to move downward relative to the piston 6, while the rams 11 of the expanding cone 10 mounted on the cone 9 of the cylinder 7 begin to grind and press the metal cup 4 with the elastic-deformed body 3 of the sealing plug 2 to the inner walls of the pipe string 31 to be sealed below violation 30.

The turning process continues until the rams 11 of the expansion cone 10 are lower than the sealing plug 2, as evidenced by the pressure drop on the pressure gauge of the pumping unit and the rams 11 of the expanding cone 10 mounted on the cone 9 of the cylinder 7 are above the sealing plug 2 '. Then, the overpressure in the casing 1 and in the under-piston space 25 of the cylinder 5 is again increased. As a result, the metal cup 4 ′ with the elastically deforming body 3 ′ of the sealing plug 2 ′ against the inner walls of the pipe string 31 to be sealed below the breach 31 ′.

A sharp jump in pressure upwards on the pressure gauge of the pump unit indicates that the piston 6 abuts against the upper end of the cylinder 5, which means the end of the turning of the sealing plugs 2 and 2 ', while the rams 11 of the expanding cone 10 are lowered down the cone 9 of the cylinder 7 together with the sleeve 13 due to the return force of the spring 12 and occupy the initial position (see figure 1).

After that, the pressure in the discharge line of the pumping unit is relieved, and the proposed device is removed from the well using the cable 24, the metal cup 4 (see Fig. 2) with the elastically deforming body 3 of the sealing plug 2, and also the metal cup 4 's the elastic-deforming body 3 'of the sealing plug 2' are tightly and hermetically pressed against the inner walls of the pipe string 31 to be sealed. Then, the necessary equipment is lowered into the well and put into operation.

The proposed device due to the fact that it is equipped with an anchor assembly is fixed in the casing of the well during the drilling of sealing plugs, and the improvement of the quality of repair of the casing of the well is achieved by sealing each violation of the casing individually, which allows to extend the life of the well until the next overhaul. In addition, the descent of the device on the cable can significantly reduce the duration of the repair, and therefore reduce the financial costs of well repair.

Claims (2)

1. A device for repairing a casing string in a well comprising a casing string and a sealing plug in the form of a hollow resiliently deformed casing with the possibility of exceeding the casing string diameter, while the resiliently casing casing is reinforced from the inside with a metal cup fixed to the bottom of the casing, the inner diameter of the metal the cup is smaller than the inner diameter of the casing in the transport position, while inside the casing above the metal cup is located a piston with a cylinder, and the bottom of the cylinder is equipped with a cone equipped with an expanding cone, made prefabricated in diameter from the dies, which are spring loaded from the top of the cylinder and configured to move only upward along the cone, and the dies are made with the possibility of pressing an elastically deformed body with a metal cup to the casing column and with a base diameter smaller than the inner diameter of the metal glass in its working position, characterized in that it is equipped with an anchor assembly above the cylinder and consisting of a hollow rod, a wedge pusher, dies and a hollow stop, while the wedge pusher is rigidly mounted on the hollow rod, which is rigidly connected to the cylinder piston, and telescopically sealed with a hollow stop with the possibility of axial movement upward, and the anchor dies nodes are placed on the hollow stem and connected to the lower end of the hollow stop with the possibility of radial movement outward when interacting with the wedge pusher; the hollow stop is equipped on the outside with a self-sealing cuff that allows liquid to pass from the bottom up, while the load equipped with radial channels is screwed onto the hollow stop from above, and the hollow rod above the wedge pusher is equipped with through holes passing fluid from the bottom up during the descent of the device into the well, and the device is lowered into the well on the cable, while the piston cavity the cylinder is in fluid communication with the interior of the casing above the self-sealing collar. 2. The device according to claim 1, characterized in that the number of sealing plugs is at least two, and they are interconnected by pipes.