RU2346143C2 - Device used for installing casing liner in well - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention refers to the building industry and operation of oil and gas wells, and namely to devices used for installing the casing liner in the well. Device consists of a liner with a hopper in upper part and conical external surface, a transport casing of the liner with a mounting seat connecting that casing with left-handed thread to the hopper having the only possibility of axial movement, and a ring seat, and upper and lower flexible cups which are installed on the liner external surface and provided with the possibility of being arranged sequentially on the side surface of the ring seat during hopper movement when transport casing is being detached, a hydraulic pusher with dies, which forms together with liner an annular chamber hydraulically connected with liner cavity in its operating position. Dies are made so that they can interact with liner conical surface.

EFFECT: improving sealing reliability of after-casing space of the liner, and simplifying the device design.

7 cl, 1 dwg

Description

The invention relates to the field of construction and operation of oil and gas wells and, in particular, to the fastening of wells by casing shanks.

A device is known for installing a casing liner in a well with a disconnector, the coupling and nipple of which are connected to each other by means of cams. The design of such a disconnector is reliable and eliminates the possibility of emergency disconnection of the transport column from the shank during its descent [1].

A disadvantage of the known device is the design complexity and the need to unload the liner to the bottom of the well to ensure that it is disconnected from the transport string, which is undesirable for the liner due to its inevitable deformations.

A device for installing a liner casing in the well, including:

- anchor assembly, providing suspension of the liner in the well string;

- node hydromechanical packer, providing a sealing annulus;

- a disconnector assembly that ensures the liner is lowered into the well and the conveyor string is subsequently disconnected from it [2].

The disadvantage of this device is its complexity, as well as the likelihood of premature actuation of the hydromechanical packer assembly, due to an unexpected increase in pressure during the cementing of the liner, and the emergence of an emergency situation associated with leaving cement slurry in the string and, therefore, its under-lifting in the annulus of the well, as well as insufficiently high reliability of sealing the annular space of the shank using the used packer.

The technical result of the invention is to simplify the device, increase the reliability of its operation as a whole and, in particular, increase the reliability of sealing the annular space of the shank.

The required technical result is achieved by the fact that the device for installing the casing liner in the well includes the liner itself with a funnel in the upper part and a tapered outer surface, a liner transport column with an installation saddle connecting this column with a left-hand thread with a funnel that can only axially move, installed on the outer surface of the shank, an annular saddle, upper and lower elastic cuffs made with the possibility of their sequential placement n the lateral surface of the annular saddle when moving the funnel in the process of disconnecting the transport column, a hydraulic pusher with dies, forming an annular chamber with a shank, hydraulically connected to the cavity of the shank in its working position, while the dies are made to interact with the conical surface of the shank, and the total height of the annular cuffs makes 0,5-1,1 height of an annular saddle.

Besides:

the funnel has a sleeve and a pusher in the lower part, and the shank against the sleeve is made with a longitudinal spline groove in which a key is placed to prevent the funnel from turning relative to the shank;

a hollow shear pin is installed in the shank to ensure hydraulic connection of the annular chamber with the shank cavity;

the outer annular saddle in its upper and lower parts has external conical surfaces;

the upper and lower annular cuffs have, each at one of their ends, protection in the form of a glass 5-10% high from the height of the corresponding cuff;

the device has a suspended hollow cementing plug located on the installation saddle;

the upper and lower annular cuffs are made, each at one of their ends, with conical surfaces and ensuring their counter interaction on the annular saddle.

The invention is illustrated by the drawing and consists essentially of a shank 1, made of composite from the upper and lower parts with different outer diameters, a sub 2 mounted on the shank 1 by means of shear pins 3, a hydraulic pusher 4, forming with the shank an annular chamber 5, separated from the cavity of the shank - it passage channel 6 with a hollow shear pin 7. The hydraulic pusher 4 by means of straps 8 and screws 9 is rigidly connected to the dies 10, designed to interact with the conical surface 11 of the shank.

The upper 12 and lower 13 elastic cuffs are installed on the shank 1, including their end protection 14, an annular saddle 16 fixed to the shank with a pin 15, a pusher 17 with an end position lock 18 interacting with the annular grooves 19 made on the upper part of the shank 1. Stop 20 eliminates the movement of the pusher 17 up during the descent of the device into the well. The funnel 21 is connected to the pusher 17 by means of a sleeve 22 and a shear screw 23. A key 24 located in the longitudinal spline groove 25 of the shank 1 eliminates the rotation of the funnel 21 relative to the shank 1. The mounting seat 26 is connected to the funnel 21 via the left trapezoidal thread 27. The upper part of the installation saddles 26 are connected to the transport column 28, and in its lower part, by means of shear pins 29, a suspended hollow suspended cementing plug 30 is installed. The necessary tightness of the device is ensured by sealing tsa 31.

The device operates as follows.

After the liner is lowered to a predetermined depth, the well is flushed through the liner shoe (not shown). After pumping the calculated volume of the cement slurry into the transport column 28, an upper cementing plug (not shown) is inserted, which sits on the hollow suspended cementing plug 30 during cementing of the well. The pins 29 are cut off and the combined plugs are moved down to the bottom of the well, cutting off the hollow pin 7 and displacing cement slurry into the annulus of the liner. At the end of the cementing process, a calculated excess pressure is created in the liner of the casing, which is transmitted through the destroyed hollow pin 7 to the annular chamber 5. In this case, the pin 3 is cut, the hydraulic pusher 4, the strips 8 are moved and the dies 10 crawl onto the conical surface 11 of the liner 1, then there is anchoring of the liner on the casing of the well (not conventionally shown). After the anchoring operation, the conveyor column 28 is rotated to the right. In this case, the funnels 21, the bushings 22, the dowels 24 move downward in the longitudinal spline groove 25, the pusher 17. As a result, the cuff 12 is placed on the lateral surface of the annular seat 16 as a result of the “creep” »Of this cuff, first on the conical, and then on the cylindrical surface of the annular seat 16. With further movement of the pusher 17, it interacts with the annular seat 16, the cut of the pin 15 and placement on the side the cuff surface of the annular seat is now the cuff 13 - also as a result of the "creep" of the cuff on the mentioned saddle. Thus, the cuffs are hermetically and reliably pressed against the inner surface of the intermediate column. Such a sealing system is reliable even with significant gaps between the liner and the walls of the well. As a possible additional sealing option, a counter interaction between the cuffs themselves can be ensured. To do this, they can be made commensurate with the length of the annular saddle or even exceed the length of this saddle to ensure their counter interaction on the annular saddle. In this case, for example, each of the cuffs at one of their ends can be made with conical surfaces. The latch 18 of the final position holds the pusher 17 in this position, which makes it possible to tightly overlap the annular space of the shank. With further rotation of the transport column 28, the screws 23 are cut off and the funnel 21 provides a free run sufficient for unobstructed flap and release of the shank with the mounting seat 26. After the flap of the transport column, excess cement slurry is washed off the “head” of the shank with the maximum possible productivity.

Information sources

1. A.I. Bulatov et al., Handbook of a drilling engineer, vol. 3, Moscow, Nedra, 1995, pp. 149-151

2. “Catalog of technical equipment kits for fastening wells with 89, 102, 114 and 127 mm shanks.”, Ryazan, Tyazhpressmash OJSC, STC ZERS LLC, 2005, pp. 32-36.

Claims (7)

1. A device for installing a casing liner in a well, including the liner itself with a funnel in the upper part and a tapered outer surface, a liner transport column with an installation saddle connecting this column with a left-hand thread with a funnel that can only axially move, mounted on the liner outer surface annular saddle, upper and lower elastic cuffs, made with the possibility of their sequential placement on the side surface of the annular saddle when moving funnel in the process of disconnecting the transport column, a hydraulic pusher with dies, forming an annular chamber with a shank, hydraulically connected with the cavity of the shank in its working position, while the dies are made to interact with the conical surface of the shank, and the total height of the annular cuffs is 0.5- 1.1 ring seat heights. 2. The device according to claim 1, characterized in that the funnel has a sleeve and a pusher in the lower part, and the shank against the sleeve is made with a longitudinal spline groove in which a key is placed to prevent the funnel from rotating relative to the shank. 3. The device according to claim 1, characterized in that a hollow shear pin is installed in the shank to provide hydraulic connection between the annular chamber and the shank cavity. 4. The device according to claim 1, characterized in that the outer annular saddle in its upper and lower parts has external conical surfaces. 5. The device according to claim 1, characterized in that the upper and lower annular cuffs each have at one of their ends protection in the form of a glass 5-10% high from the height of the corresponding cuff. 6. The device according to claim 1, characterized in that it has a suspended hollow cementing plug placed on the installation saddle. 7. The device according to claim 1, characterized in that the upper and lower annular cuffs are made each at one of their ends with conical surfaces and ensuring their counter interaction on the annular saddle.