RU59702U1 - PACKING DEVICE FOR ADDITIONAL CASING - Google Patents

Abstract

The proposal relates to the oil and gas industry, namely, to protect casing strings from high pressure and can be used when running additional casing strings into wells, the casing strings of which have become unusable. The packer device of the additional casing string consists of a body made in the form of a pipe with an elastic sleeve installed on it, an expanding assembly with a cone, a mechanism that is lowered onto the rope into the additional casing string and interacting from above with the expanding assembly. The expansion unit is located on top and is fixed with a cone down in the pipe. The mechanism is made in the form of a pusher at the bottom and an anchor assembly at the top. The pusher is made in the form of a hydraulic cylinder, made with the possibility of pressure from above on the expanding unit and equipped with a piston and a hollow rod. The hollow stem is rigidly connected to the anchor assembly from above. The lower end of the stop is rigidly mounted on top of the anchor assembly. The emphasis on the outside is equipped with a self-sealing cuff, which allows fluid to pass from bottom to top, and is tightly pressed by the collar to the inner walls of the additional casing. From above, a load equipped with radial holes is screwed into the stop. The anchor assembly is made in the form of a hollow body, inside of which are placed spring-loaded by means of springs inward slips made in the form of pistons with the possibility of radial movement outward at overpressure inside the hollow body. The proposed packer device of an additional casing string allows eliminating the spill of the borehole fluid onto the day surface, at the wellhead during the descent of the mechanism into the additional casing string, and also reduces the duration of work as a whole and simplifies the process of packing an elastic sleeve by eliminating the coarse casing from the device design , which generally reduces the cost of well repair. 1 ill. for 1 liter

Description

The proposal relates to the oil and gas industry, namely, to protect casing strings from high pressure and can be used when running additional casing strings into wells, the casing strings of which have become unusable.

It is known "Packing device of an additional casing string" (patent for utility model of the Russian Federation No. 32182, IPC 7 E 21 B 33/12, published in Bulletin No. 25 of 09/10/2003), containing a housing made in the form of a pipe with installed an elastic cuff on it, an expanding unit including a cone, and a shear element, while the body is a deformable element and is provided with a concave section from the lower end. the expanding assembly is installed inside the housing, and its cone with the outer surface is tightly pressed against the concave portion and provided with a cylindrical selection from the bottom from the inside, in which the intermediate sleeve is rigidly mounted, the assembly is equipped with a funnel with conical and cylindrical sections on the inner surface, abutting against the end of the cone and having two cylindrical samples, the upper one in contact with the upper zone of the inner surface of the cone, and the lower one rigidly connected to the fixing sleeve with the inner annular a protrusion, and a shear element is installed between the ends of the mentioned bushings and the ledges of the cylindrical samples of the cone and funnel, the inner diameters of the cylindrical section of the funnel and the annular protrusion of the fixing sleeve are selected for the diameter of the locking mechanism installed on the lower end of the tubing (tubing) lowered into an additional casing ) and equipped with an annular bore from the lower end, in which the sleeve is rigidly mounted with a conical outer cut in the upper part, and in the conical zone of the cut, a conical split ring is located that interacts in the working position with the annular protrusion of the fixing sleeve; the additional casing at the wellhead is rigidly connected to the wellhead equipment.

The disadvantages of the device:

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

secondly, mechanical packing leads to large landing forces (for aluminum pipe - 15-17 tons, for steel pipe - 35-40 tons), which compresses the additional casing, on which the packing device is lowered;

thirdly, the ability to use the device is limited by the technical characteristics of the lifting tower;

fourthly, when the landing force is removed when the pressure is removed, the additional column returns to its original state with great effort (depending on the applied force from 15 to 40 tons), which can lead to disruption from the landing site after installation.

The closest in technical essence and the achieved result to the proposed one is a packer device for an additional casing string (RF patent No. 2254441, IPC 7 E 21 B 33/12, published in bulletin No. 17 dated 06/20/2005), comprising a housing made in the form of a pipe with an elastic sleeve installed on it, an expanding unit with a cone, a shear element, a mechanism that is lowered on the pipe string into an additional casing and interacting from above on the expansion unit, while the expanding element is located in the pipe on top and the cone is fixed ohm down, the mechanism is made in the form of a pusher at the bottom and the anchor assembly at the top, and the pusher is made in the form of a hydraulic cylinder, made with the possibility of pressure from above with an expanding unit and equipped with a piston and a hollow rod, which is connected to the piston rigidly, and to the pipe string with the possibility of axial movement upward, while the anchor assembly is made in the form of dies mounted on a hollow rod with the possibility of radial movement outward when moving the hollow rod upward relative to the pipe string, shear element sits a hollow rod relative to the pipe string during descent into the well.

The disadvantages of this device are:

firstly, during the descent of the mechanism on the pipe string into the borehole, which is filled with borehole fluid, the borehole fluid is poured out of the borehole onto the surface, and therefore the drainage time is delayed and the area adjacent to the borehole is contaminated, so to avoid this, the borehole fluid must be drained in the technological tank, and after the descent of the pipe string with a mechanism at the end into the required interval of the well, it is necessary to fill the pipe string with the process fluid to drive to the action of the piston of the hydraulic cylinder of the mechanism;

secondly, the descent of the mechanism on the pipe string increases the duration of the work as a whole;

thirdly, before sealing the elastic cuff of the device, it is necessary to crimp the pipe string, at the end of which there is a mechanism, which complicates the process of sealing the elastic cuff of the device.

The technical task of the utility model is to eliminate the outflow of liquid onto the surface during the descent of the mechanism, as well as reducing the duration of the work as a whole and simplifying the process of packing an elastic sleeve by eliminating the pipe string from the device structure.

The technical problem is solved by the proposed packer device of an additional casing string, comprising a body made in the form of a pipe with an elastic sleeve installed on it, an expanding assembly with a cone, a mechanism that is lowered into an additional casing and interacting from above onto the expanding assembly, while the expanding assembly is located in the fitting above and fixed with a cone down, while the mechanism is made in the form of a pusher at the bottom and an anchor assembly with an emphasis at the top, and the pusher is made in the form of a hydraulic cylinder, pressure with an expanding unit and equipped with a piston and a hollow rod, while the hollow rod is rigidly connected to the piston.

What is new is that the mechanism descends into an additional casing string on the rope, while the hollow rod on top is rigidly connected to the anchor assembly, and the stop is equipped with a self-sealing cuff on the outside, passing fluid from bottom to top, and a load equipped with radial channels is screwed onto the stop from above. from below the emphasis is rigidly connected to the anchor unit, made in the form of a hollow body with radial holes, inside of which are placed spring-loaded slips made in the form of pistons with the possibility of radial movement on I am driving at overpressure inside the hollow body.

The figure shows the proposed device in longitudinal section.

The packer device of the additional casing string 1 consists of a housing 2 made in the form of a pipe 3 with an elastic sleeve 4 mounted on it, an expanding unit 5 with a cone 6, a mechanism 7, lowered on the cable 8 into an additional casing 1 and interacting from above with the expanding unit 5. The expanding unit 5 is located on top and fixed by a cone 6 down in the pipe 3. The mechanism 7 is made in the form of a pusher 9 at the bottom and an anchor unit 10 at the top. The pusher 9 is made in the form of a hydraulic cylinder 11, made with the possibility of pressure from above on the expanding unit 5 and equipped with a piston 12 and a hollow rod 13.

The hollow rod 13 is rigidly connected from above to the anchor assembly 10. The lower end of the stop 15 is rigidly mounted from above to the anchor assembly 14.

The stop 14 is equipped on the outside with a self-sealing cuff 15, which allows fluid to pass from the bottom up and is tightly pressed by the collar to the inner walls of the additional

casing string 1. Top load 14 is screwed with a load 16 provided with radial channels 17.

The anchor assembly 10 is made in the form of a hollow body 18 with radial holes 19, inside of which are placed spring-loaded by means of springs 20 inward slips 21, made in the form of pistons with the possibility of radial movement outward under excessive pressure inside the hollow body 18. Auxiliary fasteners are not shown in the figure .

Unauthorized fluid flows during the sealing process of the device are prevented by sealing elements 22 and 23.

The device operates as follows:

After examining the casing of the well 24, a packer is lowered into it on the additional casing 1 so that the casing 2 is lower than the disturbances (not shown) of the casing of the well 24. The upper end of the additional casing 1 is tightly and firmly fixed at the mouth (not shown) of the well 24.

After that, into the additional casing 1 on the rope 8 in the transport position (see the figure), lower the mechanism 7 until the pusher 9 of the mechanism 7 with the hydraulic cylinder 11 rests on the expanding unit 5, which is determined by reducing the weight of the load 16 and the mechanism 7 by an indicator of the weight installed at the wellhead, as well as the sagging of the rope 8.

During the descent of the rope 8, equipped with a mechanism 7 at the end, the liquid located in the additional casing 1 is transferred from the bottom up between the collar of the self-sealing cuff 15 and the inner walls of the additional casing 1 into the space of the additional casing 1 above the mechanism 7, due to the fact that the self-sealing cuff 15 passes from the bottom up, and therefore eliminates the spill of the well fluid on the surface during the descent of the mechanism 7 into an additional casing 1.

The descent of the mechanism 7 on the rope 8 into the additional casing 1 continues until the pusher 9 of the mechanism 7 with the hydraulic cylinder 11 rests on the expanding unit 5.

After that, in the additional casing 1 through the pump unit (not shown in Fig.) Create excess pressure, which first pressurizes the collar of the self-sealing sleeve 15 against the inner walls of the additional casing 1, eliminating the passage of fluid from top to bottom, and then this excess fluid pressure through radial channels 16 of cargo 17, as well as internal spaces

the stop 14, the hollow body 18 of the anchor assembly 10 and the hollow rod 13 is transferred into the space under the piston 12 in the hydraulic cylinder 11. In addition, overpressure through the radial holes 19 made in the hollow housing 18 of the anchor assembly 10 acts on the springs 20 and slips 21 made in the form of pistons, causing compression of the springs 21 and radial outward movement of the slips 21, which with their gear part fix the anchor assembly 10 of the mechanism 7 on the inner walls of the additional casing 1.

The excess pressure under the piston 2 in the hydraulic cylinder 11 continues to rise, while the hydraulic cylinder, due to the rigid fixation of the hollow rod 13 relative to the additional casing 1 by means of the anchor assembly 10, moves downward, exerting pressure on the expanding assembly 5.

At the same time, the expanding unit 5 by the cone 6 expands the pipe 3 until the elastic sleeve 4 is pressed against the additional casing 1, isolating the annulus 25 and violations (not shown) of the casing of the well 23. After passing through the pipe 3, the expanding unit 5 falls into the bottom (on Fig. Not shown) wells. As a result, the pressure inside the additional casing 1 first drops sharply, since there is no support for the hydraulic cylinder 11, and then increases sharply after the hydraulic cylinder 11 abuts the piston 12. The installation of the packer device of the additional pipe string 1 is completed. The excess pressure in the additional casing 1 is vented to zero.

Slips 21 due to the return force of the springs 20 are returned to their original position, that is, they come out of the interaction with their gear part with the inner walls of the casing 1 and radially move inside the hollow body 18 in the radial holes 19 of the anchor assembly 10. As a result, the anchor assembly 10 occupies the transport position (see figure).

After that, from the wellhead 24 by means of a rope 8, the mechanism 7 is removed from the additional casing string 1.

The force created by the hydraulic cylinder 11 during the expansion of the pipe 3 is balanced by the anchor assembly 10, then the additional casing 1 does not extend.

The proposed packer device of an additional casing string allows eliminating the spill of the borehole fluid onto the day surface, at the wellhead during the descent of the mechanism into the additional casing string, and also reduces the duration of work as a whole and simplifies the process of packing an elastic sleeve by eliminating the pipe string from the device design , which generally reduces the cost of well repair.

Claims (1)

A packer of an additional casing string, comprising a housing made in the form of a pipe with an elastic sleeve installed on it, an expanding assembly with a cone, a mechanism lowered into the additional casing and interacting from above on the expansion assembly, while the expanding assembly is located in the pipe on top and fixed by a cone down, while the mechanism is made in the form of a pusher at the bottom and an anchor assembly with an emphasis at the top, and the pusher is made in the form of a hydraulic cylinder made with the possibility of pressure from above with pa with a broadening unit and equipped with a piston and a hollow rod, wherein the hollow rod is rigidly connected to the piston, characterized in that the mechanism descends into an additional casing on the rope, while the hollow rod is rigidly connected to the anchor unit from above, and the stop is equipped with a self-sealing cuff that allows the liquid from the bottom up, with the load screwed up with radial channels being screwed up from above, the bottom being rigidly connected to the anchor assembly, made in the form of a hollow body with radial holes, inside of which odpruzhinennye slips inside, made in the form of pistons radially displaceable outwardly under positive pressure inside the hollow body.