RU2313651C1 - Device for radial reservoir exposing - Google Patents

Abstract

FIELD: oil production industry, particularly to change well bore orientation in radial direction along with window cutting.

SUBSTANCE: device comprises body with bent channel and anchor rigidly connected therewith and located downstream of the body. The body is connected with lift pipe string and may perform limited axial displacement by means of pin connection. The body has additional bent channels with inlets offset from body axis and uniformly distributed along a circle. Device has rotary bush installed over the body. The bush may rotate and has longitudinal orifice made as asymmetric funnel and figured slot. The slot is closed and extends along outer bush surface to cooperate with pin secured to lift pipe string so that as lift pipe string reciprocates relatively the body lower outlet of asymmetric funnel is successively aligned with inlet of one bent channel.

EFFECT: increased simplicity and decreased costs, provision of guaranteed cutting tool rotation and removal without body orientation change.

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Description

The invention relates to the oil and gas industry, namely to deep radial opening of the reservoir.

The well-known "Method and device for horizontal drilling of wells" (US patent No. 5413184, IPC ЕВВ 7/08, published on 05/09/1995), including a deflecting device consisting of a pipe string with a deflector for a flexible shaft or flexible pipe at the lower end .

The disadvantages of this device are:

firstly, the need for multiple operations to open sequentially operations: turning the pipe string at the required angle, lowering the flexible shaft with the cutter, cutting the channel, deepening the channel using flexible pipes with a nozzle under the influence of fluid pressure, and so for each horizontal channel that leads to large losses of time and, as a result, to material costs;

secondly, the difficulty of re-entry for additional operations in the opened channels after the rotation of the deflecting device (rotation angles are not fixed), which leads to additional costs;

thirdly, the impossibility of accurately distributing holes around the circumference, since with a large depth of the well, the angle of rotation of the pipes at the bottom is very different from the angle of rotation at the wellhead due to friction and twisting of the pipes.

The closest in technical essence and the achieved result is a device for radial opening of the reservoir (see p.31, May 2004 specialized magazine “Drilling & Oil”, Moscow, 52 p.), Including a body with a curved channel and an anchor installed below, connected to the possibility of rotation, while the curved channel is equipped with a drill with a drill bit made with the possibility of longitudinal movement downward and axial rotation, and the anchor is made in the form of a conical rod interacting with retractable dies, which matured into the spacer assembly mounted with the possibility of radial displacement.

The disadvantages of this device are:

firstly, the cutting of the window in the casing and the deepening of the horizontal wellbore are made with a drill bit, which is unprofitable;

secondly, the inability to extract, if necessary (for example, during destruction), a separate drill bit, which descends as part of the housing with an anchor;

thirdly, the difficulty of re-entering for additional operations into the drilled horizontal shaft after turning the body relative to the anchor (rotation angles are not fixed) and removing the drill bit along with the body and anchor, which leads to additional financial costs;

fourthly, the impossibility of accurately distributing holes around the circumference, since with a large depth of the well, the angle of rotation of the pipes at the bottom is very different from the angle of rotation at the wellhead due to friction and twisting of the pipes.

The technical task of the invention is the creation of a simple, cheap design of the device for radial opening of the formation with the possibility of accurate guaranteed rotation in the directions and remove the cutting tool without changing the orientation of the body with curved channels.

The technical problem is solved by a device for radial drilling, including a housing with a curved channel, located below the housing and a rigidly connected anchor.

New is that the housing is connected to the column of elevator pipes with the possibility of limited axial movement by means of a pin connection and is equipped with additional curved channels with outputs offset from the housing axis, which are evenly spaced around the circumference, while the device is equipped with a longitudinally mounted sleeve over the housing a hole in the form of an asymmetric funnel and a curly groove made closed along the perimeter of its outer surface for interaction, in turn, with a fastener a pin on the pipe string in such a way that with each reciprocating movement of the pipe string relative to the housing, the lower output of the asymmetric funnel is sequentially aligned with the entrance of one of the curved channels.

Figure 1 shows a device for radial drilling with three curved channels.

Figure 2 shows a section aa of the device.

The device for radial opening of the formation includes a housing 1 (see Figure 1) with a curved channel 2 and located below the housing 1 and the anchor 3 rigidly connected to it.

The housing 1 is connected with the column of elevator pipes 4 with the possibility of limited axial movement by means of a pin connection 5, is equipped with additional curved channels 2 (for example, three), made with inputs 6 offset from the axis of the housing 1 (see Figure 2), which are uniformly placed along circles. A sleeve 7 with a longitudinal hole 8 in the form of an asymmetrical funnel and a figured groove 9 closed along the perimeter of the outer surface of the sleeve 7 and interacting with a pin 10 fixed to the column of elevator pipes 4 in this way is mounted rotatably mounted over the housing 1 (see FIG. 1), that with each reciprocating movement of the column of elevator pipes 4 relative to the housing 1, the lower output of the asymmetrical funnel 8 is sequentially aligned with the input 6 of one of the curved channels 2.

The device operates as follows.

The device assembly on the column of elevator pipes 4 is lowered into the well (not shown) to the required opening interval. After that, the housing 1 is fixed in this interval using the anchor 3, which can be of any known design. Then, a hydraulic motor with a flexible shaft and a drill bit (not shown) is lowered into the pipe string 2 on another pipe string (not shown) or coiled tubing (not shown). Through another pipe string or coiled tubing (hereinafter referred to as the column), liquid is supplied under a pressure of 5.0-20.0 MPa, driving the hydraulic motor into rotation, while lowering the column. As a result, a drill with a flexible shaft, passing through the longitudinal hole 8 of the sleeve 7 and one of the curved channels 2 of the housing 1, drills a hole in the production casing (not shown) of the well. Then, the liquid supply to the column is stopped, after which the column with the flexible shaft is lifted until the drill is removed from the longitudinal hole 8 of the sleeve 7. Then the column of elevator pipes 4 is lifted up and lowered down relative to the housing 1 by means of their spline connection 5, turning the sleeve using a figured groove 9 the sleeve 7, interacting with the pin 10 of the column of elevator pipes 4, relative to the housing 1 until the lower output of the asymmetrical funnel 8 is aligned with the input 6 of the next curved channel 2. After that, the drilling process is operated the column using a flexible shaft with a drill and the rotation of the sleeve 7 relative to the housing 1 is repeated until the sequential use of all curved channels 2 of the housing 1.

Then the column with the flexible shaft and the drill is removed from the well and the column is lowered with a flexible pipe and a monitor head at the lower end (not shown). A liquid is supplied through the column at a pressure of 20.0-40.0 MPa while lowering the column. As a result, the hydraulic monitor head on a flexible pipe, passing through the longitudinal hole 8 of the sleeve 7, one of the curved channels 2 of the housing 1 and one of the drillings of the production string, opens the reservoir, leaving the channels of the required length (3-200 m). Then, the liquid supply to the column is stopped, and the column with the flexible pipe is lifted until the hydraulic monitor head is removed from the longitudinal hole 8 of the sleeve 7. Then the column of elevator pipes 4 is lifted up and lowered down by turning the sleeve using the figured groove 9 of the sleeve 7, interacting with the pin 5 of the column lift pipes 4, relative to the housing 1 until the lower exit of the asymmetrical funnel 8 is aligned with the inlet 6 of the next bent channel 2. After that, the process of opening the formation using a flexible pipe with a hydraulic head and by turning the sleeve 7 relative to the housing 1 is repeated until the sequential use of all curved channels 2 of the housing 1.

Then remove the column with a flexible pipe and a hydraulic head, break the anchor and the device is removed from the well. In case of technological necessity (productive formation of large thickness), the device without extraction can be installed in the next required interval of the well with the repetition of all technological operations (see above).

This device is universal and can be used with other types of equipment used for radial opening of a formation in series in several directions, for example:

- a hydraulic motor with a flexible shaft (3-4 m) and a universal drill, opening in one run the production string and the channel of small length (up to 3-5 m);

- consistently drill production casing, and then another drill with a long flexible shaft - a layer of several meters;

- a submersible motor with a flexible shaft and a cutting tool, lowered on a rope.

The design of the proposed device for radial drilling is simple, cheap, made with the possibility of guaranteed rotation in directions and removing the cutting tool without changing the orientation of the body with curved channels.

Claims (1)

A device for radial opening of the formation, comprising a housing with a curved channel located below the housing and a rigidly connected anchor, characterized in that the housing is connected to the column of elevator pipes with the possibility of limited axial movement by means of a pin connection and is equipped with additional curved channels with inputs that are offset from the axis of the housing, which are evenly spaced around the circumference, while the device is equipped with a sleeve mounted above the housing with the possibility of rotation with a longitudinal hole in the form of asymmetrical funnel and a curly groove made closed along the perimeter of its outer surface for interaction, in turn, with a pin fixed to the column of elevator pipes in such a way that with each reciprocating movement of the column of elevator pipes relative to the housing, the lower output of the asymmetric funnel is sequentially aligned with the entrance of one of the curved channels.

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