RU2387798C1 - Device for closing troublesome zone in well-drilling - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: device comprises a shutter consisting of sections of shaped tubes soldered in profile end faces, with cylindrical sites on the thread-connected ends, a flaring device with a rolling head mounted over a shaped shutter and having an assembly joint with drill pipes from the top and with the shutter from beneath. On the lower end of the shutter, there is a bearing plate with a return valve; the flaring device below the assembly joint with the shutter is provided with a head with elements interacting with the bearing plate at its top. The assembly joint with the shutter is represented by a cylindrical case with upper and lower supports on its surface the lower of which is designed to perform longitudinal motions downwards to be fixed in extreme position, and the support is provided with the rams interacting with the support to perform radial motion, and the rams of the upper and lower supports are sequenced around the cylindrical case and equipped with respectively interacting inclined surfaces designed to reduce the diametre of circumscribed circle while traveling downwards of the lower support, and the rams in their maximum diametre of circumscribed circle are designed to be fixed inside of the shutter.

EFFECT: higher reliability, reduced expenses.

2 dwg

Description

The invention relates to drilling and overhaul of wells and is intended, in particular, for local isolation of the zone of complication of the wellbore during drilling.

It is known "Device for overlapping zones of complications in the well" (patent RU No. 2270323, ЕВВ 29/10, publ. Bull. No. 5 from 02.20.2006), including a shutter from profile and cylindrical pipes, on the lower end of which is fixed a shoe with an element for disconnecting it from the overlapper, and flare cutters, the lower of which is connected to the upper end of the overlapper and has a device for interacting with the element for disconnecting the shoe from the overlapper, a unit for connecting the device to the drill pipe string and a ball check valve containing a seat, while the ball check valve seat is located above the ceiling and is made with cross channels, one of which serves to communicate the cavity of the pipe string with the annulus, and the other with the ceiling cavity, the element for disconnecting the shoe from the ceiling is made in the form of a two-stage protrusion, at the lower stage of which the slots are made, and on the top there are annular grooves, while the lower flare tool is adapted to interact with the element for disconnecting the shoe from the overlap in the form an alpaca into which a sleeve is screwed with end protrusions and slots corresponding to the splines of the lower stage of the protrusion of the shoe, and having annular grooves with stop elements mounted in them in the form of split spring rings configured to interact with the ring grooves of the upper stage of the protrusion of the shoe when disconnecting it from overlap.

The disadvantages of this device are

- the possibility of emergency situations when disconnecting the drill pipe string with flare from the cutter, since the cutter with the lower flare is connected to the right thread and if the cutter does not straighten with pressure, it is impossible to disconnect the drill pipe with flare from the cutter and lift it from the well;

- the inability to lower the shutter of large length, since it does not fill through the shoe, but through the upper valve, which, in turn, makes it difficult for the shutter to pass through the wellbore;

- the complexity of manufacturing and the high cost of the shoe due to the presence of a large number of complex parts.

The closest in technical essence and the achieved result is a “Device for blocking the complication zone when drilling a well” (patent RU No. 78514, ЕВВ 29/10, publ. Bull. No. 33 of 11/27/2008), including an overlap consisting of sections profile pipes with cylindrical sections at the ends connected by a thread, a flare machine with a rolling head located above the profile pipe and having a connection node with drill pipes at the top and an overlap at the bottom, and a shoe with a check valve is placed at the lower end of the overlap. The sections of the profile pipes are prefabricated, consisting of profile pipes with an end cylindrical section, connected by profile ends by welding, while the threads on the cylindrical sections of the sections of the profile pipes are tapered and equipped with a sealing compound, the external conical thread being placed at the lower end of the sections of the profile pipes, and the internal - on top, while the flare bottom is equipped with a rolling head with cutting elements made with the possibility of opening the shoe.

The disadvantages of this device are

- the possibility of emergency situations when undocking the connection node from the overlap, since the overlap with the connection node is connected on the right-hand thread and in case of failure to correct the overlap, it is impossible to disconnect the drill pipe string with the connection node from the overlap and lift it out of the well;

- the need to use an additional rolling head of complex design, which leads to a significant increase in the cost of equipment.

The technical task of the proposed device is to create a reliable and cheap design due to the use of a connection unit with a shutter made in the form of a sliding cylinder, with the possibility of reducing the outer diameter, which eliminates emergency situations when disconnecting a drill pipe string with a flare from the shutoff.

The technical problem is solved by a device for blocking the complication zone when drilling a well, including a shutter, consisting of sections of profile pipes connected by profile ends by welding, with cylindrical sections at the ends connected by a thread, a flare with a rolling head located above the profile overlap and having a connection node with drill with pipes at the top and a shutoff at the bottom, with a shoe with a non-return valve placed at the lower end of the shutoff, with a flare below the joint Perekryvatel head equipped with elements capable of cooperating with the shoe when the lapel.

What is new is that the connection unit with the overlap is made in the form of a cylindrical body with upper and lower stops located on its surface, the lower of which is made with the possibility of longitudinal downward movement with fixation in the extreme position, while the stops are equipped with dies interacting with the stops with the possibility of radial movement, moreover, the dies of the upper and lower stops are placed alternately around the cylindrical body and are equipped with inclined surfaces interacting respectively with each other d with the possibility of reducing the diameter of the circumscribed circle when moving the lower stop down, and the dies with their maximum diameter of the circumscribed circle are made with the possibility of fixing inside the overlap.

Figure 1 shows a device for blocking the complication zone when drilling a well before distributing a profile blocker with internal hydraulic pressure.

Figure 2 shows a device for blocking the complication zone when drilling a well after distributing a profile blocker by internal hydraulic pressure and undocking the connection node from the blocker.

A device for blocking the zone of complication when drilling a well comprises a blocker 1 (see Fig. 1 and 2), consisting of sections 2 of profile pipes 3 with cylindrical sections 4 at the ends connected by a thread 5, a flare 6 with a rolling head 7, placed above the block 1 and having a connection node with drill pipes 8 at the top and a connection node with an overlap 9 at the bottom, and at the lower end of the overlap 1 there is a shoe 10 with a check valve 11.

Sections 2 of profile pipes 3 are prefabricated, consisting of profile pipes 3 with an end cylindrical section 4 each, connected by profile ends by welding 12. The flare 6 is equipped with a head 13 with elements made with the possibility of interaction with the shoe 10 during its opening.

The connection node 9 with the overlap 1, includes the upper 14 and lower 15 stops, and the lower stop is made with the possibility of longitudinal movement downward with fixing in the extreme position by means of a locking device, for example a locking ring 16. The stops 14 and 15 are equipped with dies 17, which have inclined surface 18 (see Figure 2), interacting respectively with each other, with the possibility of reducing the diameter of the circumscribed circle when moving the lower stop 15 down. Moreover, the dies 17 with their maximum diameter of the circumscribed circle are made with the possibility of fixing inside the overlap 1, for example, the left thread 19 (see Figure 1) (or in another way - rolling the pipe, etc.).

The device operates as follows.

Section 2 (see Figure 1) of the overlap 1, connected by profile ends by welding 12, starting from the bottom, is sequentially lowered into the well, connecting them using threads 5 located at the ends of the cylindrical sections 4 of the profile pipes 3. Moreover, the lower section 2 is equipped with a shoe 10 with a non-return valve 11, and the upper one with left-hand thread 19 under the connection unit with the overlap 9.

Next, to the left-hand thread 19 of the upper section 2, a flare 6 is connected by a knot of connection with the overlap 9, with a head 13 located below with elements made with the possibility of interaction with the shoe 10 during its opening. Then, on the drill pipe string (not shown in the drawing) connected to the flare 6 by the connection unit with drill pipes 8, the device is lowered into the installation interval (not shown in the drawing). In this case, the downhole fluid fills the device through the check valve 11 of the shoe 10. After that, overpressure is created in the drill pipe string, which is transmitted to the shutter by shutting off the check valve 11 of the shoe 10 and straightens the profile sections of the profile pipes 3 until they interact with the well walls, fixing the overlap 1 relative to the well. Next, the drill string is given the right rotation, as a result, the joint assembly with the overlap 9 (see FIG. 2) is disconnected from the thread 19. Then the drill string together with the joint assembly 9 and the head 13 are lifted up to the distance necessary to move the lower stop 15 together with the head 13 under the influence of its own weight and the reaction of the walls of the borehole down until the locking device 16. The dies 17, interacting with each other by means of inclined surfaces 18 and with stops 14 and 15, also move, and the diameter the circumference described by the dies 17 decreases and becomes smaller than the inner diameter of the cylindrical sections of the profile pipes. After that, the flare 6 is given a rotational-translational movement downward, expanding and tightly pressing cylindrical sections 4 and calibrating the profile sections of the profile pipe 3 with the rolling head 7 of the flare 6 and calibrating the profile sections of the profile pipe 3. Upon reaching the shoe 10, the head 13 turns it away, after which the shoe falls to the bottom, and the head 7 of the flare 6 fully presses the shutter 1 against the walls of the well, hermetically isolating the interval of the complication zone when drilling the well.

The proposed device is a simple and reliable design due to the use of the connection node with the shutoff, made in the form of a sliding cylinder, with the possibility of reducing the outer diameter, which eliminates emergency situations when disconnecting the drill pipe string from the shutoff.

Claims (1)

A device for blocking the zone of complication during well drilling, including a shutter, consisting of sections of profile pipes connected by profile ends by welding, with cylindrical sections at the ends connected by a thread, a flare with a rolling head located above the profile cutter and having a connection node with drill pipes at the top and with a shutter at the bottom, and at the lower end of the shutter there is a shoe with a check valve, while the flare is equipped with a hollow below the connection to the shutter with elements made with the possibility of interacting with the shoe during its flap, characterized in that the connection unit with the overlap is made in the form of a cylindrical body with upper and lower stops located on its surface, the lower of which is made with the possibility of longitudinal downward movement with fixation in the extreme position, while the stops are equipped with dies, interacting with the stops with the possibility of radial movement, and the dies of the upper and lower stops are placed alternately around a cylindrical rpusa and equipped with inclined surfaces interacting respectively with each other to reduce a diameter of the circumscribed circle when moving downward lower stop, wherein the ram when the maximum diameter of the circumscribed circle made fixable inside Perekryvatel.

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