RU2378489C1 - Device for overlapping troublesome zone during well boring - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: device includes overlapping device consisting of shaped tube sections with cylindrical sections on ends which are connected to thread; roller flaring tool located above shaped tube and having component to be connected to overlapping device. On lower end of overlapping device there arranged is shoe with check valve. Shaped tube sections are assembled and consist of shaped tubes with end cylindrical section, connected with shaped edges by means of welding. Threads on cylindrical sections are conical and equipped with sealing compound. Outside conical thread is arranged on lower end of shaped tube sections, and inside thread - above. On cylindrical section of upper section facing the flaring tool there made is internal chamfer, and on external surface there made are annular grooves. Flaring tool is equipped from below with cutting head made with possibility of interacting and breaking the shoe which is made from easy-drillable material, and from above - with additional expandable flaring tool.

EFFECT: reliability is improved, design is simplified and cheapened.

3 dwg

Description

The proposal relates to the drilling and overhaul of wells and is intended, in particular, for the 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, IPC ЕВВ 29/10, publ. Bull. No. 5 from 02.20.2006), including a blocker from profile and cylindrical pipes, on the lower end of which a shoe is fixed 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 overlap, a unit for connecting the device to the drill pipe string and a ball check valve containing at the same time, the seat of the ball check valve is placed above the overlap 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 cavity of the shutter, the element for disconnecting the shoe from the shutter is made in the form of a two-stage protrusion the lower stage of which the slots are made, and the upper one has annular grooves, while the lower flare device for interacting with the element for disconnecting the shoe from the overlap is made in de cap into which a sleeve is screwed with end protrusions and slots corresponding to the splines of the lower stage of the shoe protrusion 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 shoe protrusion when disconnecting it from overlap.

The disadvantages of this device are:

- the inability to lower the shutter of great length, because due to the lack of a valve in the lower part of the shutter does not fill and align the external and internal pressures;

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

- a large investment in manufacturing time during descent to assembly of the overlap and during flaring due to the presence of a large number of connecting threads;

- to ensure free passage of the drilling tool through the profile cutter during subsequent drilling, it is necessary to further expand the profile cutter with an enlarged flare, as an “end effect” occurred in the upper part of the cylindrical section of the upper section of the profile pipes, and the existing flare is not sliding and has limited application possibilities.

The closest in technical essence and the achieved result is "Device for blocking the complication zone in the well" (patent RU No. 2310737, IPC ЕВВ 29/10, publ. Bull. No. 32 from 11/20/2007), including an overlap consisting of sections in the form of profiled pipes with cylindrical sections at the ends connected by a thread, an expander with a turning or rolling head located above the profiled pipe and having a connection unit for drill pipes, and a shoe with a check valve is placed on the lower end of the overlap, and on the cylindrical sections of the profile pipe, the internal thread is equipped with inner ring grooves, the external thread is equipped with the corresponding inner ring grooves, the inner ring protrusion, while the external thread of the cylindrical section of the profile pipes is equipped with the outer ring grooves, and the inner thread with the outer ring grooves, the outer ring protrusion, the outer and inner ring grooves the protrusions are equipped respectively with annular outer and inner thickenings corresponding to the outer m and an internal bore.

The disadvantages of this device are:

- the complexity of manufacture and the high cost of connecting threads of the overlap due to the presence of external and internal grooves and the corresponding internal and external protrusions;

- the complexity of manufacturing and the high cost of shaped pipes due to the high accuracy requirements in the manufacture of shaped pipes with cylindrical end sections;

- time-consuming when expanding the overlap due to the presence of a large number of connecting threads;

- to ensure the free passage of the drilling tool through the profile cutter during subsequent drilling, it is necessary to further expand the profile cutter with an enlarged flare, as an “end effect” occurred in the upper part of the cylindrical section of the upper section of the profile pipes, and the existing flare is non-expanding and has limited application possibilities;

- the need to use the complex design of the shoe for its removal and lifting to the surface, which leads to the cost of all work.

The technical task of the proposed device is to create a simple, reliable and cheap design of the overlap by simplifying the manufacture of shaped pipes, making self-sealing, forcibly sealed tapered thread, using an expanding flare, as well as a simpler and cheaper installation method by reducing the time spent on flaring the overlap in the well, and the destruction of the shoe for one tripping operation during expansion.

The technical problem is solved by a device for blocking the complication zone when drilling a well, including a cutter, consisting of sections of profile pipes with cylindrical sections at the ends connected by a thread, a roller flare placed above the profile pipe and having a connection unit with a cutter, and a shoe is placed on the lower end of the cutter with check valve.

What is new is that sections of shaped pipes are prefabricated, consisting of shaped pipes with an end cylindrical section, connected by profile ends by welding, and threads on the cylindrical sections of sections of shaped pipes are tapered and equipped with a sealing compound, and the external conical thread is placed on the lower end of the sections of shaped pipes, and the inner one from above, while on the cylindrical section of the upper section of the profile pipes facing the roller flare, an inner chamfer is made, and on the outer surface is annular grooves, and the roller flare bottom is equipped with a cutting head, made with the possibility of interaction and destruction of the shoe, which is made of easily drilled material, and on top with an additional sliding flare, the outer diameter of which in the working position exceeds the diameter of the wellbore.

Figure 1 shows the upper part of the device.

Figure 2 shows the lower part of the device.

Figure 3 shows a fragment of the upper part of the cylindrical section of the upper section of profile pipes.

A device for blocking the zone of complication when drilling a well (not shown) includes a blocker 1 (see Figs. 1 and 2), consisting of sections 2 of profile pipes 3 (see Fig. 2) with cylindrical sections 4 at the ends connected by a thread 5, a roller flare 6 (see FIG. 1) located above the profile pipe 7 and having a connection unit 8 with a blocker 1. A shoe 9 with a check valve 10 is placed at the lower end of the blocker 1.

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 11. Threads 5 on the cylindrical sections of 4 sections 2 of profile pipes 3 are made conical and equipped with a sealing compound (not shown). The outer conical thread 12 (see Figure 2) is placed on the lower end of the sections 2 of the profile pipes 3, and the inner 13 is on top. On the cylindrical section 14 of the upper section of the profile pipes 7, facing the roller flare 6, an inner chamfer 15 is made, and on the outer surface, annular grooves 16 (see figure 3). Roller flare 6 below is equipped with a cutting head 17, made with the possibility of interaction and destruction of the shoe 9, which is made of easily drilled material. On top of the installed additional sliding flare 18, the outer diameter of which in the working position exceeds the diameter of the wellbore (not shown).

The device operates as follows.

Profile pipes 3 are made with one cylindrical section 4, which is equipped with internal 13 or external 12 conical threads. Moreover, such profile pipes 3 are simpler and cheaper to manufacture than with two cylindrical sections 4. Then, the profile pipes 3 are selected in pairs with the external 13 and internal 12 threads on the cylindrical sections 4, the profile ends of the pair profile pipes are calibrated and rigidly and hermetically connected by welding 11 getting sections 2 of profile pipes 3, twice as long as standard ones. The lower section 2 is equipped with a shoe 9 with a check valve 10, which are made of easily drilled material. Roller flare 6 (see Fig. 1) is located above the profile tube 7 and has a connection unit 8 with a blocker 1. In addition, the flare flare 6 is equipped with a cutting head 17 below. An additional expanding flare 18 is installed above the roller flare 6, the outer diameter of which is working position exceeds the diameter of the wellbore.

After delivery of section 2, starting from the bottom, they are sequentially lowered into the well, connecting sections 2 with threads 12 and 13 with a sealing compound so that the cylindrical sections 4 with external thread 12 are located below, with internal thread 13 above. Then, on a drill pipe string (not shown) connected to the expanding flare 18 (see FIG. 1), the device is lowered into the installation interval (not shown). In this case, the borehole fluid fills the device through the check valve 10 (see Fig. 1) of shoe 9. After that, overpressure is created in the drill pipe string, which is transmitted through the central channel 19 of the flare tool to the shutter by closing the check valve 10 of shoe 9 and straightens the profile sections of the profile pipes 3 (see Fig. 2) until their tight interaction with the walls of the well, fixing the shutoff 1 relative to the well. Next, the drill pipe string is rotated, as a result of which the arrangement of the roller flare 6 and the expanding flare 18 is disconnected from the shutoff 1 due to the connection unit with the shutoff 8 (see Fig. 1). Then, simultaneously with fluid injection and rotation of the drill pipe string, they are given translational movement downward, by flaring and tightly pressing cylindrical sections 4 (see Fig. 2) and calibrating profile sections of the profile pipe 3 by rolling flare 6 and expanding flare 18, and upon reaching shoe 9 made of easily drilled material, a roller flare 6 with a cutting head 17 destroys it, and flare 6 and 18 completely press the shutter 1 against the walls of the well, hermetically from lating interval complications zone during drilling the well.

Due to the fact that the outer conical thread 12 (see figure 2) is located on the lower end of the sections 2 of the profile pipes 3, and the inner 13 is on top, equipped when connected with a sealing compound (for example, plastic adhesive), when expanding, the inner cylindrical section 4 with an external taper thread 12 "flows" onto the outer cylindrical section 4 with an internal taper thread 13, eliminating leakages when installing the shutoff 1 in the well. And due to the fact that the inner chamfer 15 is made on the cylindrical section 14 of the upper section of the profile pipes 7, and the annular grooves 16 are made on the outer surface, the upper part of the overlap is tightly pressed against the well wall, thus eliminating the "end effect". When using the expanding flare 18, free passage of the drilling tool through the profile overlap 1 is ensured during subsequent drilling, since the outer diameter in the working position exceeds the diameter of the wellbore. Due to the fact that the roller flare 6 from the bottom is equipped with a cutting head 17, made with the possibility of interaction and destruction of the shoe 9, which is made of easily drilled material, there is no need for additional tripping to destroy the shoe at the bottom.

The proposed device is a simple, reliable and cheap design due to the simplification of the manufacture of the shutter from shaped pipes with one cylindrical section, the presence of a self-sealing, forcibly sealed tapered thread, as well as a more reliable, simple and cheap way to install it, it is guaranteed to flush, as well as reducing costs. on making up the threads of the overlap before lowering it into the well and breaking the shoe in one round trip during flaring.

Claims (1)

A device for blocking the zone of complication during well drilling, including a shutter, consisting of sections of profile pipes with cylindrical sections at the ends connected by a thread, a roller flare placed above the profile pipe and having a connection unit with a shutter, with a check valve on the lower end of the shutter characterized in that the sections of the profile pipes are prefabricated, consisting of profile pipes with an end cylindrical section, connected by profile ends by welding, and the threads on the cylindrical sections of the sections of the profile pipes are tapered and equipped with a sealing compound, the outer conical thread being placed on the lower end of the sections of the profile pipes and the inside on top, while on the cylindrical section of the upper section of the profile pipes facing the roller flare, an inner bevel and on the outer surface - annular grooves, and the roller flare bottom equipped with a cutting head, made with the possibility of interaction and destruction of the shoe, which is made of easily drilled material, and on top - an additional sliding flare, the outer diameter of which in the working position exceeds the diameter of the wellbore.

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