RU49089U1 - DEVICE FOR CEMENTING A TAIL IN A WELL - Google Patents

Abstract

The proposal relates to the oil industry, specifically to the construction and repair of wells. The device for cementing the liner in the well includes an inner and outer case, and in the lower part of the outer case there are windows, a check valve, a seat interacting with the inner case, and bypass channels communicating with the outer space through the windows of the outer case are made in the walls of the inner case. The shank on top is equipped with a sleeve equipped with an internal left-hand thread and a removable sub equipped with an external left-hand thread, which is screwed from below to the upper end of the inner casing, and from above - into the internal left-hand thread of the sleeve, the sleeve being connected from below to the shank, below which the seat is sealed the upper end of the outer casing, equipped with longitudinal through grooves and pushed on top of the aforementioned shank. Inside the outer casing, a movable saddle is installed hermetically, equipped with an annular sampling from below, while the inner casing is muffled from below and is connected via a shear element to a non-return valve made in the form of a hollow muffled from below a cylinder having an annular sampling on the outer surface in which there is a retaining ring having the ability to interact with the ring selection of the movable saddle. Toothed notches are made on the outer surface of the outer case, and on the outside it is equipped with a packer made in the form of a folding rubber sleeve rigidly connected to the upper and lower stops, the upper stop being fixedly fixed to the outer case. The lower stop is equipped with an internal groove in which a position lock is made, made in the form of a spring ring, interacting in the working position with the serrated notches of the outer casing. The lower emphasis is made with the possibility of axial movement upward relative to the outer casing and is connected to the movable seat by means of destructible pins installed in the longitudinal through grooves of the outer casing. The proposed device has a simple design, which allows to reduce material production costs, and the increase in the reliability of its operation is associated with the exclusion of ball clamps from the device design and the cork plug from the process, which allows cementing the liner regardless of its length and weight in any interval of the well.

Description

The proposal relates to the oil industry, specifically to the construction and repair of wells.

A disconnecting device is known (patent RU No. 2136840 IPC 7 E 21 B 17/06, 43/10, publ. Bulletin No. 25 of 09/10/1999), including internal and external housings with ball retainer made with the possibility of telescopic interaction with each other between them, a saddle made with the possibility of telescopic interaction with the inner housing and the ball retainer, while the device is equipped with an installation pipe, and the saddle is equipped with an annular retaining ring and is made with the possibility of additional telescopic interaction with ruzhnym body.

The disadvantage of this device is its low reliability, associated with:

firstly, with a weak catch of ball retainers when cementing sufficiently long shanks with a large weight, because premature operation of ball retainers can lead to an emergency in the well;

secondly, with the fact that when pushing the cement plug, it is possible to slip through the stop ring and, as a result, a violation of the cementing technology of the shank;

thirdly, the use of cementing plugs complicates the construction of wellhead fittings.

The closest in technical essence to the proposed is a disconnecting device for cementing shanks with support on the face (patent RU No. 2149252 IPC 7 E 21 17/06, 43/10, publ. Bulletin No. 14 of 05/20/2000), including made with the possibility of telescopic interaction between the inner and outer shells with a ball retainer between them, a saddle made with the possibility of telescopic interaction with the inner shell and a ball retainer, while in the lower part of the outer shell there are windows over which the passage channel of the said casing is provided with a seat for the check valve interacting with the inner casing, while in the walls of the inner casing there are bypass channels communicating with the outer space through the passage channel of the seat and the windows of the outer casing.

The specified device to one degree or another has all the disadvantages noted above. In addition, it is complex in design, due to the large number of parts, and failure to meet stringent requirements in the manufacture and assembly reduces the reliability of the device.

The objective of the utility model is to simplify the design of the device and increase the reliability of its operation, regardless of the length and weight of the liner, as well as the exclusion of the cork plug from the process when cementing the liner in the well.

This problem is solved by a device for cementing the liner in the well with support on the bottom, including an inner and outer casing, a check valve, a seat interacting with the inner casing, the inner space of which communicates with the outer space through the windows of the outer casing.

New is that the device on top is equipped with a coupling equipped with a left-hand thread and a removable sub, which is screwed from below to the upper end of the inner case, and from above - into the left-hand thread of the coupling, with the coupling connected to the shank at the bottom, below which the seat is sealed on the upper end the outer casing, equipped with longitudinal through grooves and pushed on top of the aforementioned shank, while inside the outer casing a movable saddle is installed hermetically equipped with an annular selection from below, at Ohm, the inner casing is muffled from below and is connected via a shear element to a non-return valve made in the form of a hollow muffled from below a cylinder having an annular sampling on the outer surface, in which a retaining ring is placed that can interact with the annular sampling of the movable saddle, and on the outer surface of the outer casing serrated notches are made, and on the outside it is equipped with a packer made in the form of a folding rubber sleeve rigidly connected to the upper and lower stops, the upper the emphasis is fixed on the outer casing rigidly, and the lower emphasis is provided with an internal groove in which a position lock is made in the form of a spring ring interacting in the working position with the serrated notches of the outer casing, the lower emphasis being made with the possibility of axial upward movement relative to the outer casing and connected to the movable saddle by means of destructible pins installed in the longitudinal through grooves of the outer casing.

The figure shows the proposed device for cementing the liner in the well in longitudinal section.

A device for cementing the liner 1 (see figure) in the well contains an inner 2 and an outer 3 body. Windows 4 are made in the lower part of the outer casing 3. The lower casing 3 is equipped with a crown 5 from the bottom and screwed into the coupling 6 from the top, and the saddle 7 is hermetically installed in the inner cylindrical groove of the shank 1.

The saddle 7 on the inner surface is equipped with a sealing element 8, through which it tightly interacts with the inner casing 2.

In the outer casing 3, longitudinal through grooves are made 9. Inside the outer casing 3, a movable saddle 10 is sealed, equipped with a bottom ring 11 and a sealing element 12 on the inner surface hermetically interacting with the inner casing 2. On the outer surface of the outer casing 3, gear notches 13 are made, and outside it is equipped with a packer 14, made in the form of a folding rubber sleeve 15, rigidly connected to the upper 16 and lower 17 stops. The upper stop 16 is fixed on the outer casing 3 rigidly.

The lower stop 17 is provided with an internal groove 18, in which a position lock 19 is installed, made in the form of a spring ring, interacting in the working position with the serrated notches 13 of the outer casing 3.

The lower emphasis 17 is made with the possibility of axial movement upward relative to the outer casing 3 and is connected to the movable seat 10 by means of destructible pins 20 installed in the longitudinal through grooves 9 of the outer casing 3.

The inner casing 2 is muffled from below and is connected via a shear element 21 to a non-return valve 22 made in the form of a hollow muffled from below a cylinder having an annular sampling 23 on the outer surface, in which a retaining ring 24 is placed that can interact with the annular sampling 11 of the movable seat 10.

The inner space of the inner casing 2 by means of radial holes 25 made in its lower part communicates with the outer space through the windows 4 of the outer casing 3.

At the top, the device is equipped with a coupling 26 equipped with an internal left-hand thread 27 and a removable sub 28 with an external left-hand thread 29, which is screwed from below by an adapter 30 onto the upper end of the inner case 2. At the top, a removable sub 28 with its external left-hand thread 29 is screwed into the internal left-hand thread 27 a clutch 26 to which a shank 1 is screwed from below.

The device operates as follows.

On top of the outer casing 3, with a packer installed on its outer surface and a movable saddle located inside it, connected to the lower stop of the packer, a coupling 6 is screwed, a saddle 7 is hermetically installed in the inner cylindrical groove of the lower shank pipe 1. After that, extend the shank 1 to the required length.

Then, at the wellhead (not shown) in the upper casing of the liner 1, a coupler 26 with an internal left thread 27 is screwed and the assembled structure is mounted on the elevator.

Next, the inner casing 2, consisting of a pipe string, and provided with a check valve 22 from below, is lowered into the assembled structure with a length measurement, with the saddle 7 first having its own sealing element 8, and then the movable saddle 10 with its sealing element 12 hermetically interacting with the outer surface inner casing 2.

In the process of lowering the inner casing 2 with the check valve 22 at the end when passing the saddle 7 and the movable saddle 10, the circlip 24 is compressed in the annular sample 23 of the check valve 22, and bypassing their inner surfaces it is again expanded.

The descent of the inner casing 2 is continued until the additional check valve 22 reaches the window location interval 4 of the outer casing 3.

After that, to the upper end of the inner casing 2 by means of the adapter 30, a removable sub 28 with an external left thread 29 is fitted and connected, which, in turn, is screwed into the internal left thread 27 of the coupler 26.

The elevator is removed from the wellhead and, using the tubing string 31, the device is lowered all the way to the bottom of the well or a pre-installed cement bridge that acts as a support (not shown).

Then, the removable sub 28, and therefore the inner case 2 connected to it, is disconnected by turning the removable sub 28 from the left-hand thread 27 of the coupler 26 by rotating the tubing string 31 clockwise from the wellhead, while the crown 5 fixes the outer case 3 and shank 1 from cranking. After making sure that the removable sub 28 is disconnected from the coupler 26, as indicated by the load drop on the weight indicator (weight loss of the shank 1),

installed at the wellhead (not shown in FIG.), the upper end of the tubing string 30 is attached to the wellhead (for example, a faceplate).

Next, the calculated volume of cement mortar is pumped into the tubing string 31 and squeezed using a squeeze fluid through the radial holes 25 of the inner casing 2 and the window 4 of the outer casing 3 into the outer space.

In this case, the estimated volume of cement slurry, pressed into the outer space rises up between the liner 1 and the wall of the well (not shown in FIG.) Until it reaches the coupler 26.

At the end of the sale, the tubing string 31 is lifted up until the retaining ring 24 installed in the annular sample 23 of the check valve 22 abuts against the cylindrical sample 11 of the movable seat 10.

The tubing string 31 continues to be lifted upward, while the movable saddle 10 and connected to it by means of destructible pins 20 installed in the longitudinal through grooves 9 of the outer casing 3, the lower stop 17 move upward, while the folding rubber sleeve 15 of the packer 14 starts to seal.

The packing process continues until the destructible pins 20 are cut off, while the position lock 19, made in the form of a spring washer, installed in the inner groove 18 of the lower stop 17 is fixed in the serrated notches 13 of the outer case 3.

The presence of a packer eliminates the crushing of cement into the reservoir due to the weight of the column of cement and reduces the impact of this column on the check valve 14 in the fixed position.

Next, the tubing string 31 is again raised up until the movable seat 10 located on the inner casing 2 rests on the seat 7. Continue to pull the tubing 31 upwards, that is, increase the load directed upwards and when the rated load is reached (greater shear force of the destructible pins 20) shear element 13 is destroyed, as evidenced by the first growth, and then a sharp drop in the readings on the weight indicator installed on the wellhead.

As a result, the retaining ring 23 is finally fixed in the annular groove 11 of the movable seat 9, and the check valve 22 hermetically closes the passage channel of the movable seat 9, due to the pressure from below.

After that, the tubing string 31 is again raised upward by 3-5 meters, while the inner casing 2 goes out of interaction with the movable saddle 10 and saddle 7.

Then, by direct or reverse washing, the excess cement mortar is washed out of the inner space of the liner 1. After that, the column is completely removed

Tubing 31 with an inner casing 2 from the well. In the well, the outer casing 3, the seat 7, the check valve 22, the movable seat 10, which are made of easily drilled materials and are subsequently drilled, remain.

The proposed device has a simple design, which allows to reduce material production costs, and the increase in the reliability of its operation is associated with the exclusion of ball clamps from the device design and the cork plug from the process, which allows cementing the liner regardless of its length and weight in any interval of the well.

Claims (1)

A device for cementing a liner in a well, including telescopically mounted inner and outer shells, a saddle with a check valve, while windows are made in the lower part of the outer shell, and channels communicating with the outer space through the windows of the outer shell are characterized in that that the inner case is muffled from below and equipped with a check valve fixed with a shear screw, made in the form of a plug with a retaining ring, and from above is equipped with a removable sub, equipped externally the left-hand thread interacting with the internal left-hand thread, made in the upper part of the outer casing, which is provided with longitudinal through grooves between the windows and the internal thread and with a rigidly fixed annular sleeve and a saddle located top to bottom, movable with the possibility of axial movement limited by destructible pins, installed in the longitudinal through grooves, and the annular sleeve and the movable saddle are made with the possibility of sealing the inner space between the inside external and external housings, while the additional saddle from the bottom is equipped with an annular selection made with the possibility of interaction with the retaining ring, on the outer surface of the outer housing there are serrated notches and a packer made in the form of a folding elastic sleeve rigidly connected to the upper and lower stops, the upper of which fixed relative to the outer casing, and the bottom is made movable in the axial direction, connected to a destructible pin and equipped with a position lock, made th a circlip cooperating in the operative position with the toothed notches.