RU2420653C1 - Device for local enlargement of profile and cylinder pipes in well - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: device consists of case with central channel having threads for connection with downhole equipment and also having inclined slots. Supports with rolling elements are positioned in the channels and are designed to slide in them. The rolling elements are made in form of ball segments on axles set under angle to the axis of the case. The device further consists of a mechanism advancing the rolling elements into a working position. The mechanism corresponds to a circular sealed pusher travelling lengthwise and interacting with the case. The circular pusher is made as a circular cylinder mounted on the case and fixed from turning over. The circular cylinder and the case in its upper part form a hydraulic chamber communicated with the central channel of the case. On the case, in the hydraulic chamber of the cylinder wherein a circular internal groove is made, there is positioned a mechanism for holding the rolling elements in an idle position. This mechanism consists of segments of a hollow bush spring loaded outward and with cone surface on top. They interact with the circular groove of the cylinder. Also, above the segments there is positioned an additional circular piston equipped with an internal face interacting with cone surface of the segments when moving downward to take them out from the circular groove of the cylinder.

EFFECT: increased reliability and service life and reduced accident rate.

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Description

The invention relates to drilling and overhaul of wells and is intended, in particular, for flaring profile or cylindrical pipes when installed in the well.

It is known “Device for expanding pipes in a well” (RF patent No. 2225498, E21B 29/10, publ. Bull. No. 7 of 03/10/2004), including a housing with a central channel, threaded elements for connection with downhole equipment and recesses in the outer wall, in which the rolling elements mounted on the axes in the supports are placed, the supports being installed in inclined grooves made in the recesses of the housing with the possibility of longitudinal sliding relative to the housing along an inclined surface, the device being equipped with a roller extension mechanism the operating elements in the working position, made in the form of an annular piston placed in the central channel of the housing with an axially spring-loaded rod, pivotally connected to the supports by means of rods, the outer surface of the rolling elements being made spherical.

The disadvantages of this device are:

- high radial loads directly on the axis, significantly reducing their service life;

- low quality flared pipes, since the rollers of the device are equipped with narrow calibrating sections;

- low reliability, since in the event of a spring breakage, the ring piston may jam in the operating position and cannot return to the transport position, which can lead to an emergency;

- insufficient strength of the housing of the device due to the need to perform in it drilling under the annular piston and thrust;

- high demands on the accuracy of manufacturing the mechanism for the extension of the rolling elements to the working position, due to the large number of mating parts and their relative position relative to each other, because rolling elements after putting them into working position should be on the same circumscribed circle.

The closest in technical essence and the achieved result is “Device for pipe expansion” (RF patent for utility model No. 62148, E21B 29/10, publ. Bull. No. 9 of 03/27/2007), including a housing with a central channel, threads for connection with downhole equipment and recesses on the outer surface, in which the rolling elements mounted on the axes in the bearings are placed, and the supports are installed in inclined grooves made in the recesses of the housing with the possibility of longitudinal, relative to the housing, sliding along the inclined surface while the device is equipped with a mechanism for extending the rolling elements into the working position, made in the form of an annular piston located in the central channel of the housing with an axially spring-loaded rod, pivotally connected to the supports by rods, the outer surface of the rolling elements being spherical, and the rolling elements being made in the form of spherical segments, the axis of which is installed at an angle to the axis of the housing, while at the end of the supports removable stops are installed that limit the maximum output d diameter rollers elements.

The disadvantages of this device are:

- low reliability, since in the event of a spring breakage, it is possible to jam the annular piston in the working position and the inability to return it to the transport position, which can lead to an emergency during tripping;

- insufficient strength of the housing of the device due to the need to perform in it drilling under the annular piston and thrust;

- high demands on the accuracy of manufacturing the mechanism for the extension of the rolling elements to the working position, due to the large number of mating parts and their relative position relative to each other, because rolling elements after putting them into working position should be on the same circumscribed circle.

The technical task of the proposed device is to increase its reliability by hardening the body of the device and reducing the mating parts, as well as the elimination of emergency situations during operation and tripping operations of the device due to the reliable fixation of the rolling elements in the working and transport positions.

The technical problem is solved by a device for the local expansion of profile and cylindrical pipes in the well (hereinafter referred to as the device), including a body with a central channel, threads for connecting to downhole equipment and inclined grooves, in which bearings with rolling elements made in the form of spherical segments are slidably mounted on axes mounted at an angle to the axis of the housing, and a mechanism for extending the rolling elements to the working position, made in the form of an annular tight pusher with the possibility of th longitudinal movement interacting with the body.

What is new is that the annular pusher of the extension mechanism to the working position is made in the form of an annular cylinder mounted on the casing and secured against rotation, forming a hydraulic chamber communicating with the central channel of the casing in its upper part, while on the casing, in the cylinder’s hydraulic chamber, which has an annular inner groove, a mechanism is placed for fixing the rolling elements in the inactive position, containing outwardly segments of the hollow sleeve with a tapered surface at the top, stvuyuschie with the annular groove of the cylinder, and a further annular piston located above the segments and provided with an internal chamfer interacting with a conical surface segments while moving downward to output them from the annular groove of the cylinder.

Figure 1 shows the device in the working position, partially in section; figure 2 is a section aa in figure 1; figure 3 is a fragment of the device, which shows the locking mechanism of the rolling elements in the inoperative position; figure 4 is a section bB in figure 3.

The device (Fig. 1) comprises a housing 1 with a central channel 2, threads 3 for connection with downhole equipment and inclined dovetail grooves 4, in which bearings 5 are placed with sliding possibility with rolling elements made in the form of spherical segments 6 on axes 7 installed at an angle to the central axis of the housing 1, and a mechanism for extending the rolling ball segments 6 into the working position, made in the form of an annular tight due to, for example, elastic sealing rings 8 and 9 of the pusher 10 with the possibility longitudinal movement relative to the housing 1 and interaction on the supports 5 with the rolling elements 6 through radial holes 11 in the lower part of the pusher 10.

The ring pusher 10 of the extension mechanism to the working position is made in the form of an annular cylinder 12 mounted on the housing 1 with surfaces 13 fixing it against rotation in the housing 1 (Fig. 2), interacting with the mating surfaces 14 of the housing 1 (Fig. 1).

The annular cylinder 12 forms, with the housing 1 in its upper part, a hydraulic chamber 15 communicating with the central channel 2 of the housing 1 by means of a side hole 16. Moreover, on the housing 1, in the hydraulic chamber 15 of the annular cylinder 12, due to the inner annular groove 17 (FIG. 3) , placed a mechanism for fixing the rolling ball segments 6 (figure 1) in the inoperative (transport) position, containing spring-loaded outward, using springs 18 (figure 3, 4), segments 19 of the hollow sleeve with a tapered surface 20 (figure 3) at the top, interacting with the reciprocal ring groove 21 of the cylinder 12, and an additional annular piston 22 with O-rings 23 and 24 located above the segments 19 and provided with an inner chamfer 25 interacting with the conical surface 20 of the segments 19 when moving down to withdraw them from the annular groove 21 of the cylinder 12.

The device operates as follows.

Using the threads 3 (FIG. 1) of the housing 1, the device is connected to a drill pipe string (not shown) and lowered into a well (not shown). In this case, the annular pusher 10 with the cylinder 12 is fixed from longitudinal displacements relative to the housing 1: down - with its annular stop 26, which abuts the annular protrusion 27 of the cylinder 12, up - with the annular segments 19 (Fig. 3), the edges 28 of which are in the annular groove 21 cylinders 12.

At a given depth of the well, the drill pipe string begins to rotate with the simultaneous supply of flushing fluid (drilling fluid) into it, which, under the influence of the pressure drop arising due to the hydraulic nozzle 29 (Fig. 1) in the central channel 2 of the housing 1 and propagating through the side opening 16 of the housing 1 into the hydraulic chamber 15, acts on an additional annular piston 22. In this case, the piston 22 is hermetically, thanks to the sealing rings 23 and 24, moves downward and, acting with its chamfer 25 (Fig. 3), tangentially on the hole the distinctive taper surface 20 of the segments 19, moves them along the longitudinal axis of the device into the outer grooves 17 of the housing 1, compressing the springs 18 until the annular segments 19 exit completely from the recesses 21 of the cylinder 12.

Having thus disengaged from the housing 1 (Fig. 1), the annular pusher 10 with the cylinder 12, under the same pressure differential, moves up to the stop of the inner annular protrusion 30 of the pusher 10 into the lower annular stop 31 of the housing 1. At the same time, the pusher 10 acts on the supports 5 with rolling elements 6, which, moving along the inclined grooves 4 of the housing 1 tangentially upward, are discharged through the radial holes 11 of the pusher 10 to the working position. Further, by feeding the tool downward while rotating it, sections of the pipe pre-expanded by hydraulic pressure of the profile pipes or cylindrical pipes (not shown) begin to expand in a predetermined interval. In this case, the rolling elements 6, rotating on the axes 7, expand the pipe sections until they are pressed firmly against the walls of the casing (for example, when installing the liner) or in the well (when overlapping drilling complication zones).

After completion of the work, the injection of flushing fluid is stopped, and the device is lifted from the well. In this case, the supports 5 with rolling elements 6, having reached the unexpanded part of the pipes, will stop the upward movement of the pusher 10 with the cylinder 12, while the housing 1 with the latch 19 (Fig. 3) continues to move upward relative to them. Due to this, the supports 5 with the rolling elements 6, freed from the action of the latch 19, under the reaction forces of the walls of the unexpanded part of the pipes will return due to the inclined grooves 4 to their original position inside the housing 1.

The proposed device due to the more robust housing and the minimum number of mating units and parts allows reliable and trouble-free flaring of profile and cylindrical pipes, and the mechanism for sliding the rolling elements into the working and back to the transport position, due to the clear fixation in extreme positions, increases the service life of the device and eliminates emergency situations during tripping.

Claims (1)

A device for the local expansion of profile and cylindrical pipes in the well, including a housing with a central channel, threads for connecting to downhole equipment and inclined grooves, in which bearings with rolling elements made in the form of spherical segments on axes mounted at an angle to the axis of the housing, and the mechanism for extending the rolling elements to the working position, made in the form of an annular tight pusher with the possibility of longitudinal movement, interacting with housing, characterized in that the annular pusher of the extension mechanism to the working position is made in the form of an annular cylinder mounted on the housing with rotation locking, forming with the housing in its upper part a fluid chamber communicating with the central channel of the housing, while on the housing, in the cylinder hydraulic chamber, in which the annular inner groove is made, a mechanism for fixing the rolling elements in the inactive position is placed, containing segments of the hollow sleeve spring-loaded outward with a conical surface at the top, interacting ones with the annular groove of the cylinder, and a further annular piston located above the segments and provided with an internal chamfer interacting with a conical surface segments while moving downward to output them from the annular groove of the cylinder.

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