RU2381351C1 - Tool for main and lateral boreholes of one well hermetic connection - Google Patents

Abstract

FIELD: oil-and gas industry.

SUBSTANCE: invention related to oil-and gas industry, particularly to multi-borehole wells fixing tools. Includes casing strings of a main and additional boreholes and a connection pipe. A connection pipe located in the casing string additional borehole upper part and equipped with boreholes connection sealing element. A basement executed as a sleeve with a bottom slot. The sleeve segment and the connecting pipe executed with ability to be directed to additional borehole using wedge - incliner, installed for the additional borehole bypassing, orienting with the use of the slot, interacting with wedge technological step, and tough interaction with the casing string internal surface around the lateral borehole window with help of hermetic and tack rolling.

EFFECT: multi-borehole well boreholes reliable and hermetic fixing, also providing possibility of multi-borehole well construction form bottom to the top and from the top to the bottom as well, due to excluding of the main borehole bypass cross section narrowing, wide application area.

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Description

The invention relates to devices for attaching multi-hole wells and can be used for attaching multi-hole wells drilled for oil, gas, water and for other purposes.

A device for attaching multilateral wells (AS USSR No. 663825, ЕВВ 43/10, publ. Bulletin No. 19 of 05.25.79), including casing strings of the main and additional shafts, a connecting pipe located in the upper part of the casing columns of the additional barrel and rigidly connected to the corrugated sleeve located in the main barrel.

The disadvantages of the device are:

- narrow scope and high capital costs associated with the fact that for the installation of the device requires a large difference in the diameters of the main and additional shafts;

- the need to use an additional guide device for getting the casing string into the side trunk;

- the difficulty in uniformly tearing the corrugated sleeve due to the fact that its diameter is much smaller than the inner diameter of the main barrel.

Closest to the claimed technical essence is a device for attaching multilateral wells (AS USSR No. 829882, ЕВВ 43/10, publ. Bulletin No. 18 of 05/17/81), including corrugated casing of the main and additional shafts a sleeve located in the main shaft and connected to a connecting pipe installed in the upper part of the casing of the additional wellbore, and having a smooth section and longitudinal slots at its border with the corrugations.

The disadvantages of the device are:

- the use of a partially corrugated sleeve, which is associated with difficulties in its manufacture and, as a result, with high material costs for manufacturing;

- the need to use an additional guide device for getting the casing string into the side trunk;

- a significant narrowing of the bore of the main shaft, which allows the construction of a multilateral well only from the bottom up, which narrows the scope.

The technical task of the invention is to increase the reliability of the connection of the main and additional shafts of a multilateral well, while maintaining an equal bore section of the main well, eliminating the need to use a guiding device to enter the side well, and also the ability to construct a multilateral well, either from the bottom up or from top to bottom.

The technical problem is solved by a device for the tight connection of the main and lateral shafts of a multilateral well, including casing strings of the main and additional shafts and a connecting pipe with a base located in the upper part of the casing of the additional well, the base being made with the possibility of tight and tight interaction with the inner surface of the casing main trunk around the window.

What is new is that the base is made in the form of a segment of a sleeve with a lower slot, and the outer surfaces of the base, and the nozzle, and the place of their junction are equipped with a sealant, and the nozzle is made with the possibility of directing it to the additional barrel using a wedge-deflector installed for wiring an additional barrel , and orientation using the bottom slot of the base interacting with the technological protrusion of the deflector wedge, and tight and tight interaction with the inner surface of the casing of the main core La around the side window due to sealant and rolling.

Figure 1 schematically shows the proposed device in a multilateral well.

In Fig.2 and 3 - connecting pipe with a base and sealant, side view and rear, respectively.

Figure 4 - the device in the process of installing it in the well.

A device for the tight connection of the main 1 (see Fig. 1) and the lateral 2 trunks of a multilateral well consists of casing strings 3 and 4, respectively, of the main 1 and additional 2 shafts and a connecting pipe 5 with a base 6 located in the upper part of the casing 4 of the additional well 2. The base 6 is made with the possibility of tight and tight interaction with the inner surface of the casing 3 of the main shaft 1 around the window 7 (see figure 1). The base 6 (see figure 2 and 3) is made in the form of a segment of the sleeve with a bottom slot 8, and the outer surfaces of the base 6, and the pipe 5, and the place of their junction are equipped with sealant 9. The pipe 5 (see figure 4) is the possibility of directing into the additional barrel 2 through the window 7 using the wedge-deflector 10, installed for posting the additional barrel 2, and orientation using the lower slot 8 of the base 6, interacting with the technological protrusion 11 of the wedge-deflector 10, and tight and tight interaction with the internal casing surface itna 3 (see figure 1) of the main barrel 1 around the window 7 of the side trunk 2 due to the sealant 9 and rolling (not shown). The base 6 and the connecting pipe 5 are located relative to each other at an angle α (see figure 2), equal to the angle of departure α '(see figure 1) of the additional barrel 2 from the main 1. Base 6 (see figure 2 and 3 .) may have a chamfer 12 for unstressed operation of a flare tool (not shown) along its inner contour.

The device can be used when working in two versions.

First option

The casing 3 of the main bore 1 is lowered into the initially drilled main bore 1 (see FIG. 4) of the multilateral well, the layout of which includes a pipe with a window 7 through which an additional bore 2 is passed. To the last pipe of the casing 4 of the additional bore 2 or the last pipe of the column of profile pipes (not shown) intended for fastening the side trunk, connect the nozzle 5 with the base 6 using an integral connection (for example: welding) (not shown) or detachable connection (for example: thread 13) (see figure 1). Then, using, for example, a landing head (not shown) fixed in the connecting pipe 5 (see FIG. 4), they are lowered onto the drill pipe string (not shown) into the well. When the casing 4 of the additional barrel 2 or the core pipe string approaches, they are deflected and introduced into the additional side barrel 2 using the diverter wedge 10 (for example, the retractable diverter wedge OI-168 or OI-146) pre-installed and fixed mainly barrel 1 (for example: using anchor 14). In this case, the base 6 with its lower slot 7 sits on the technological protrusion 11 of the diverter and is installed in the required position (figure 1). After that, the landing head is released and the drill pipes rise to the surface. Then the wedge-deflector 10 is removed (see FIG. 4) with an anchor 14, the flare is lowered into the well and the base 6 is rolled (see FIG. 1) with sealant 9 to the inner surface of the casing 3.

If it is necessary to post several additional shafts 2, the required number of nozzles with windows 7 is included in the layout of the main casing 3, and the casing 4 of additional shafts 2 is installed sequentially after 7 wedges 10 installed and oriented relative to their windows.

Second option

The casing 3 of the main shaft 1 is lowered into the initially drilled main bore 1 (see Fig. 4) of the multilateral well 1. The wedge-deflector is installed in the well (for example: the removed wedge-deflector ОИ-168 or ОИ-146) and window 7 is sequentially cut and drilling an additional barrel 2. Next, the installation of the casing 4 of the additional barrel 2 is carried out similarly to the first embodiment.

If necessary, the wiring of several additional shafts 2 operations are performed similarly to the second option in different intervals and directions of the casing 3 of the main trunk 1.

The proposed device is a simple and low-cost construction, due to the fact that the base is made in the form of a segment of the sleeve, when installing it does not require a guide device, which is part of the device for getting into the additional barrel. Due to the fact that a chamfer is made along the inner contour of the base, and sealant is applied to the outer surface of the sealing element adjacent to the cut-out window, the base tightly rolls around the window in the casing, which ensures reliable and tight fastening of multilateral wells and virtually eliminates the narrowing of the bore the main trunk. Since the main cross-sectional section is preserved, it becomes possible to build a multilateral well both from bottom to top and from top to bottom, which greatly expands its scope.

Claims (1)

A device for tightly connecting the main and lateral shafts of a multilateral well, including casing strings of the main and additional shafts and a connecting pipe with a base located in the upper part of the casing of the additional shafts, the base being made to tightly and tightly interact with the inner surface of the casing of the main shafts around windows, characterized in that the base is made in the form of a segment of the sleeve with a lower slot, and the outer surfaces are based I and the nozzle and the place of their junction are equipped with a sealant, and the nozzle is made with the possibility of directing to the additional barrel with the help of a diverter installed for the additional barrel, and orientation with the help of the bottom slot of the base, which interacts with the technological protrusion of the diverter, and a dense and tight interaction with the inner surface of the casing of the main trunk around the sidewall window due to sealant and rolling.

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