RU2425953C1 - Overlapping device of troublesome zone during well drilling - Google Patents

Abstract

FIELD: oil and gas industry. ^ SUBSTANCE: device includes overlapping device consisting of connected sections of shaped tubes with cylindrical sections on ends, the main and additional roller-type flaring device, which are connected to overlapping device by means of connection and having cutting head from below for destruction of shoe during contact. There is shoe with non-return valve on lower end of overlapping device, and there is inner chamfer on upper end. Inner chamfer is made on lower end of overlapping device; at that, on upper and lower ends of overlapping device there uniformly made along the perimetre from the edge are through cuts having the possibility of formation of upper and lower flared ends bent outwards after expansion of overlapping device with roller-type flaring devices. ^ EFFECT: higher reliability and enlarged manufacturing capabilities of the device. ^ 4 dwg

Description

The invention relates to the oil and gas industry, and in particular to devices for isolating the zone of complication of a wellbore while drilling.

It is known “Device for overlapping zones of complications of drilling in a well” (patent RU No. 2270323, E21B 29/10, publ. Bull. No. 5 of 02.20.2006), including a shutter from profile and cylindrical pipes, on the lower cylindrical section 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 an element for disconnecting the shoe from the overlapper, a unit for connecting the device to the drill pipe string and ball return a valve comprising a seat, the seat of the ball check valve placed above the ceiling and made with cross channels, some of which serve to communicate the cavity of the drill pipe string with the annulus, and others to the cavity of the shutter, the element for disconnecting the shoe from the shutter is made in the form of a two-stage protrusions, on the lower stage of which longitudinal slots are made, and on the upper - annular grooves, while the device of the lower flare for interacting with the element for disconnected The shoe from the overlap is made in the form of a cap into which a sleeve is screwed with end protrusions and slots corresponding to the splines of the lower step 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 annular upper grooves the steps of the protrusion of the shoe when disconnecting it from the overlap.

The disadvantage of this device is the presence of an “end effect” at the ends of the overlap (that is, the ends of the overlap due to elastic deformation after expansion of the overlap by the flare retreat into their cylindrical sections, thereby reducing the diameters of the passage sections at the entrance and exit of the overlap), which may cause further problems with the passage of downhole equipment through the shutoff.

The closest to the claimed technical essence and the number of matching essential features is "Device for blocking the complication zone when drilling a well" (patent RU No. 2378489, E21B 29/10, publ. Bull. No. 1 from 01/10/2010), including a shutoff 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 shutoff, moreover, a shoe with a check valve is placed on the lower end of the shutter, and sections Ofilen pipes, they 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 profile pipes are tapered and equipped with a sealing compound, the external conical thread located at the lower end of the section of profile pipes, and the internal thread at the top while in 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 of the rings 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.

The disadvantage of this device, as in the first case, is the presence of an “end effect” at the lower end of the overlapper, in addition, the presence of an internal chamfer and external annular grooves at the upper end of the overlapper, although they reduce the effect of elastic deformation, but do not allow creating a sufficient socket at the entrance after distributing it with a roller flare distributor, which is especially relevant when one or both ends of the overlap gets into the cavity (void), i.e. there is a problem with the passage of the downhole equipment tions through Perekryvatel remains unresolved in this case.

The technical objectives of the invention are to increase the reliability and expand the technological capabilities of the device associated with the trouble-free passage of downhole equipment through it by creating at the ends of the overlap when it is installed in the well, a sufficient socket bent outward, including when placing the ends of the overlap in cavernous sections.

The technical problem is solved by a device for blocking the complication zone when drilling a well, including a shutter, consisting of connected sections of profile pipes with cylindrical sections at the ends, a main and additional roller flare, connected to the shutter by a connection unit and having a cutting head from below to destroy the shoe upon contact, moreover a shoe with a check valve is placed on the lower end of the overlapper, and an internal chamfer is made on the upper end.

What is new is that an inner chamfer is made at the lower end of the overlapper, while at the upper and lower ends of the overlapper, through cuts are made uniformly around the perimeter from the end, made with the possibility of forming the upper and lower sockets bent outward after the overlap is expanded by roller flare.

Figure 1 shows a device for blocking the complication zone when drilling a well in a transport position (partially in section); figure 2 - view And figure 1 (enlarged); figure 3 and 4, respectively, views B and C in figure 1 (enlarged).

A device for blocking the zone of complication when drilling a well comprises a blocker 1 (Fig. 1) arranged from sections of profile pipes 2 with cylindrical sections 3 at the ends of sections 2 connected, for example, by means of a thread 4. Upper cylindrical section 5 of the upper section 2 the overlap 1 is equipped with the main 6 and, above it, an additional 7 roller flare with a connecting unit 8 in the form of a right through thread for connecting flare 6 and 7 with the upper section 2 of the overlap 1. Flare 6 and 7 are equipped with from the cutting head 9 to destroy the shoe 10 upon contact. The shoe 10 is made of easily drilled material, equipped with a check ball valve 11 and is located in the lower cylindrical section 12 of the lower section 2 of the overlap 1.

On the upper cylindrical section 4 of the upper section 2 of the overlap 1, facing the additional flare 7, an inner bevel 13 is made (Fig. 2). The same chamfer 13 (Fig. 3) is made on the lower cylindrical section 12 of the lower section 2 (Fig. 1) of the overlap 1. Moreover, through cuts 14 are made uniformly around the perimeter from the end face of the upper 5 and lower 12 cylindrical sections of the overlap 1 (Fig. 3). 4), ending with the aim of eliminating the stress concentration during mechanical action with holes 15 and a length not exceeding the difference in radii at the beginning and end of the lead-in portion of the roller of the flare 7 facing them (Fig. 1), and configured to form upper and lower races pipes, bent outward, after the expansion of the overlap 1 roller flare 6 and 7.

The device operates as follows.

Before lowering into a borehole (not shown) in the lower cylindrical section 12 of the lower section of the profile pipes 2, for example, a shoe 10 with a check ball valve 11 is fixed using thread 16, and in the upper cylindrical section 5 of the upper section of the profile pipes 2 on the through thread 8 set the primary and secondary flare 6 and 7 with a cutting head 9.

Then the sections of the profile pipes 2, starting from the bottom, are sequentially lowered into the well, connecting them together by cylindrical sections 3 using threads 4, and on the drill pipe string (not shown) connected to the upper flare 7, the device is lowered into the installation interval (not shown). In this case, the borehole fluid fills the internal cavity of the overlap 1 through the check ball valve 11 of the shoe 10.

After that, in the drill pipe string using a mud pump, excessive hydraulic pressure is created, which is transmitted through the central channels 17 of the flarers 6 and 7 to the internal cavity of the overlap 1 and, by closing the check ball valve 11 of the shoe 10, straightens the profile sections of the sections 2 until they are pressed firmly against the walls of the well, fixing the overlap 1 relative to the well.

Then, by turning the drill pipe string to the right, the flarers 6 and 7 are unscrewed from the thread 8 of the upper cylindrical section 5 of the upper section 2 of the overlap 1, and, creating a load, the cylindrical sections 3 of the sections of the profile pipes 2 are expanded, and also the unexpired remaining after the hydraulic pressure expansion of the sections of the profile pipes 2 to more tightly pressing them to the walls of the well.

Upon reaching the shoe 10, the main flare 6, thanks to the cutting head 9, destroys it, coupled with the additional flare 7, the lower cylindrical section 12 of the overlap 1. Then the layout, consisting of flare 6, 7 and the cutting head 9 on the drill pipe string, is removed from wells.

Due to the through cuts 14 (Fig. 4) at the upper and lower ends of the cylindrical sections 5 (Fig. 1) and 12 of the overlap 1, when distributing them with a roller flare 7, successive bending of each of the segments 18 (Fig. 4) of the cylindrical sections 5 (figure 1) and 12, separated by notches 14 (figure 4), eliminating the effect of elastic deformation and creating essentially the upper and lower sockets, sufficient for trouble-free passage of downhole equipment. And the inner chamfer 13 (figure 2, 3) while directing the deviated downhole tool inside the overlap 1 (figure 1).

The invention allows to increase the reliability of the device and expand its technological capabilities when used in wells with a large number of caverns by creating at the ends of the overlap when it is installed, a sufficient socket bent outward and allowing trouble-free passage of well equipment through the shutter.

Claims (1)

A device for blocking the zone of complication during well drilling, including a shutter, consisting of connected sections of profile pipes with cylindrical sections at the ends, a main and additional roller flare, connected to the shutter by a connection node and having a cutting head from below to destroy the shoe upon contact, and at the lower end a block with a check valve is placed on the overlap, and an inner chamfer is made on the upper one, characterized in that an inner flange is made on the lower end of the overlap a cut, while at the upper and lower ends of the overlapper, through cuts are made evenly around the perimeter from the end face, made with the possibility of forming the upper and lower sockets bent outward, after the overlap is expanded by a roller flare.

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