RU2601711C1 - Device for extraction of long-length pipe - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention can be used for emergency extraction column or sections of long-length pipe from well. Device includes a hollow housing, connected through a cup with an adapter. In axial channel of cup there is a central core provided with a cone with a conical surface on lower end. Annular piston is rigidly coupled with core and forms with hollow housing a chamber in which there is a spring with a support on annular piston and cup. Inside housing under annular piston there is a conical piston with formation of a circular cavity, permanently hydraulically connected with radial holes in body of annular piston with axial channel of core. Housing in bottom part comprises an inner taper surface whereon rests outer gripping element in form of plates with T-like ledges. Under conical piston there is a spacer sleeve in which there are T-shaped grooves in which T-shaped ledges of plates are arranged, on inner surface of which there is a notch. In body of spacer sleeve on inner surface there is an annular groove to receive a split spring ring, retaining plates. Under conical piston in housing there are drain holes. On cone there is an inner gripping element in form of separate plates with a notch and outer annular groove in middle part, in which there is a split spring ring for their pressing simultaneously to conical piston and to conical surface of cone on central core. Outer and inner gripping elements are installed with possibility of axial and radial movement.

EFFECT: higher reliability of gripping, enabling adjustment of gripping force and obtaining information on operation of device.

1 cl, 3 dwg

Description

FIELD OF THE INVENTION

The invention relates to the oil and gas industry, in particular to a device for extracting a long pipe, and can be used in fishing devices for emergency extraction of columns or sections of a long pipe from a well.

State of the art

There is a well-known internal tubing for tubing fishing, which consists of a housing on which dies with teeth are mounted, while on the housing there is a clip on which springs are mounted, a guide head is fixed at the lower end of the housing, and a special lock is installed in the upper part of the housing to communicate with column of pipes.

The operation of the tube consists in introducing the tube into the emergency pipe with the control of input according to the GIV. The springs are in contact with the inner walls of the pipes. The holder with dies stops the body when interacting with the inner surface of the pipe. The dies are located in the upper part of the housing, which allows them to be charged by rotation and pulling. The column is rotated half a turn to the left. When moving the tube up, the dies slide along an inclined surface in the housing and interact with the inner wall of the pipe. Pulling upward leads the pipe to the surface (see Basarygin Yu.M., Makarenko P.P., Mavromati B.D. Repair of gas wells. - M.: Nedra Publishing House OJSC, 1998, p. 206 -208).

The disadvantages of this tube are:

- the inability to apply for the extraction of pipes of small diameter having a small wall thickness, which can lead to pipe rupture;

- the drive of the tube for unfastening it inside the pipe to the left by 1/2 turn, which is quite difficult to control from the surface.

A known outer tube, which consists of a connecting pipe with a connecting thread for connecting to the drill pipe string, a coupling with a gasket and a protector equipped with a shoe is screwed onto the lower end of the housing, and a die and a spacer secured by the coupling are installed inside the housing, a spring is located inside the coupling, this coupling is screwed to a sleeve provided with a starter.

Emergency pipes are covered with a pipe with landing control according to the GIV. The spacer interacts with the end of the tubing, the pins enter the grooves, the dies slide down onto the conical part in the axial channel of the tubing body and embrace the extracted pipe with force from the outside (see Basarygin Yu.M., Makarenko P.P., Mavromati V.D. Repair of gas wells. - M.: Nedra Publishing House OJSC, 1998, S. 208-210).

The disadvantages of this tube are:

- deposition of the spacer and the movement of the plate towards the conical part is carried out due to the efforts of the pre-compressed spring. Elements (die) are moved to the axis of the device with the introduction of teeth into the body of the extracted pipe, while the force developed by the spring may not be enough to reliably capture the pipe;

- to design a pipe for emergency extraction of pipes of small diameter according to such a structural scheme is problematic, since for small diameters of the device it is problematic to have a spring with a large axial force in order to reliably capture the emergency pipe;

- when capturing outside pipes of small diameter while maintaining large diametrical dimensions of the body, when it is possible to use springs with large overall dimensions and high axial force, there is a possibility of crushing the end of the emergency pipe, which will cause difficulties in removal.

The closest in technical essence and the achieved positive effect and adopted by the authors for the prototype is a tube that contains a hollow body with an inner conical surface in the lower part, a sub rigidly connected to the hollow body. Inside the hollow body, an external gripping element and an internal gripping element are installed, having the possibility of axial movement. The spacer sleeve is mounted on an external gripping element. The conical piston is mounted on the core with support on the spacer sleeve.

The core is fixed with a nut and spring loaded with a return spring relative to the hollow body. In the middle part, the core is made in the form of an annular piston with radial inclined holes below it, with the formation of an annular cavity hydraulically connected with a common axial channel.

An external gripping element is mounted on the inner conical surface of the housing and is made in the form of a split sleeve with a ribbed inner surface and a conical outer surface.

An internal gripping element is mounted on the central core between the conical piston and the centering cone with the possibility of axial movement relative to the external gripping element and is made in the form of a split sleeve with a ribbed outer surface and an inner surface in the form of converging upper and lower cones.

The surface of the upper cone is the mating outer conical surface of the conical piston, and the lower one is the outer conical surface of the centering cone (see US Pat. No. 2352755, IPC ЕВВ 31/20, published on 04/20/2009, bull. No. 11).

The disadvantages of this tube are low operational reliability, due to several reasons:

- the implementation of the outer and inner gripping elements in the form of split sleeves, with the outer and inner ribbed surfaces, requires significant axial forces to deform these split sleeves in the radial direction and reliable gripping of the pipe;

- when the split sleeves are deformed in the radial direction, their contact with the pipe wall does not occur along its entire perimeter, which does not reliably produce adhesion to the pipe material, if the ribbed surface interacts insufficiently with it.

Disclosure of invention

The task of the invention is to develop a device for extracting a long pipe, having:

- the possibility of high reliable capture of the end of the emergency pipe with the simultaneous commissioning of the internal and external exciting elements during the interaction of their ribbed surfaces with the pipe body along the perimeter;

- the ability to regulate the gripping force of the emergency pipe body by the exciting elements with a minimum pressure of the working fluid;

- the ability to accurately obtain information about the operation of the device in case of impracticability to capture the end of the emergency pipe with exciting elements.

The technical result that can be obtained by implementing the present invention is reduced to high reliability of gripping the end of the emergency pipe with the simultaneous commissioning of the internal and external exciting elements when their ribbed surfaces interact with the pipe body along the perimeter, and the gripping force of the emergency pipe is captured by the gripping elements when the minimum pressure of the working fluid and the accurate receipt of information about the operation of the device in case of impracticability to capture the end of the emergency pipe for grabbing elements

The technical result is achieved using a device for extracting a long pipe containing a hollow body with an inner conical surface in the lower part, a sub, a central core with a cone at the lower end installed in the axial channel of the hollow body, the outer and inner gripping elements installed in the hollow body with the possibility of axial and radial movement, spacer sleeve, conical piston, spring loaded piston with radial holes connecting the annular cavity between the the central and conical pistons with the axial channel of the central core, while the hollow body is equipped with drainage holes made under the conical piston, the external gripping element is made in the form of dies equipped with T-shaped protrusions and a spacer sleeve provided with mating T-shaped bores for the protrusions of the dies and an internal annular groove for a split spring ring mounted with the possibility of contact with an external gripping element, the internal gripping element being made in the form of dies with a ring the groove on the outer surface, equipped with a split spring ring installed with the possibility of simultaneous pressing of the dies to the conical piston and to the conical surface of the cone on the central core.

Thus, the technical result is achieved due to the fact that the hollow body is provided with an inner conical surface in the lower part, a sub, a central core with a cone at the lower end installed in the axial channel of the hollow body. The external and internal exciting elements mounted in a hollow housing with the possibility of axial and radial movement, a spacer sleeve, a spring-loaded conical piston, an annular piston with radial holes connecting the annular cavity between the annular and conical pistons with the axial channel of the central core.

Additionally, the hollow body is equipped with drainage holes made under the conical piston.

The outer gripping element is made in the form of dies equipped with T-shaped protrusions, the spacer sleeve is provided with mating T-grooves for the protrusions of the dies and an inner annular groove for a split spring ring installed with the possibility of contact with external gripping elements. The internal gripping elements are made in the form of dies with an annular groove on the outer surface, in the middle part equipped with a split spring ring installed with the possibility of simultaneously pressing the dies to the conical piston and to the cone, on the central core.

Brief description of drawings and other materials

In FIG. 1 shows a device for extracting a long pipe, in a section in the initial transport position.

In FIG. 2 - the same, the relative position of the parts of the device when capturing the end of the emergency pipe;

In FIG. 3 - same, the installation site of the dies in the support ring.

The device consists of a hollow body 1 connected through a glass 2 with an adapter 3. A central core 4, provided with a cone 5 with a conical surface 6 at the lower end, is passed into the axial channel of the glass 2. The annular piston 7 is rigidly connected with the central core 4 and forms a chamber 8 with a hollow body 1, in which a spring 9 is placed with support on the annular piston 7 and the cup 2, a conical piston 10 is placed inside the hollow body 1 under the annular piston 7 to form an annular cavity 11 permanently hydraulically connected by radial holes 12, in the body of the annular piston 7, with an axial channel 13 of the central core 4. The hollow body 1 in the lower part contains an inner conical surface 14, on which an external gripping element rests 15 in the form of dies 16 (see Fig. 3) having T-shaped protrusions 17. Under the conical piston 10 there is a spacer sleeve 18 in which T-shaped bores 19 are made, in which T-shaped protrusions 17 of the dies 16 are placed, on the inner surface of which has a notch 20. In the body of the spacer sleeve 18, an annular groove 21 is made on the inner surface, in which a split spring ring 22 is mounted that holds the dies 16 in the T-bores 19 of the spacer sleeve 18. Under the conical piston 10 in the body of the hollow body 1 made drainage holes 23. N and the cone 5 has an internal gripping element 24, made in the form of separate dies with a notch 25 and an outer annular groove 26 in the middle part, in which a split spring ring 27 is placed for pressing them simultaneously to the conical piston 10 and to the conical surface 6 of the cone 5 on the central the core 4, the outer and inner gripping elements 15 and 24, respectively, are installed in the hollow body 1 with the possibility of axial and radial movement, and at the upper end of the central core 4 there is a nut 28 with its fixation.

The device has small diametric dimensions and can be used in the axial channel of tubing with an outer diameter of 73 mm with an inner diameter of 62 mm.

A device for extracting a long pipe is operated as follows.

A device for extracting a long pipe (not shown in FIG.) Is connected through the sub 3 to the lower end of the pipe string and introduced into the axial channel of the pipe pipe string to the location of the upper end of the long emergency pipe.

The lower end of the cone 5 with the conical surface 6 at the lower end is inserted into the axial channel of the emergency pipe with a passage into the axial channel of the hollow body 1, with the location between the inner and outer gripping elements 24 and 15, respectively, with the central core 4 passing into the axial channel of the cup 2, fixed by a nut 28, provided with a cone 5 with a conical surface 6 at the lower end, then the working fluid is supplied under pressure to the axial channel of the pipe string with the transmission of this pressure from the axial channel 13 through the radial holes 12 annular cavity 11. A conical piston 10 located under the annular piston 7, the latter being rigidly connected to the central core 4 and form a chamber 8 with the hollow body 1, in which the spring 9 is placed resting on the annular piston 7 and the cup 2, moves axially downward the channel of the hollow body 1 with the impact on the spacer sleeve 18, which moves down together with the dies 16, interacting with the inner conical surface 14 in the hollow body 1, while in the body of the spacer sleeve 18, an annular groove 21, in which a split spring ring 22 is mounted that holds the dies 16 in the T-bores 19 of the spacer sleeve 18. Turning the T-shaped protrusions 17 inside the T-shaped bores 19, the dies 16 move downward, interact with the inner conical surface 14 in the floor case 1, which leads to their movement to the axis of the device with the introduction of notches 20 into the body of the emergency pipe.

Simultaneously with the axial downward movement of the dies 16 of the external picking member 15, the conical piston 10 with the formation of an annular cavity 11 is inserted under the dies with notches 25 of the internal picking member 24, which, when interacting with the conical surface 6 of the cone 5, move radially to the inner surface of the emergency pipe with the introduction of notch 25 into her body. The capture is carried out simultaneously by the dies of the outer gripping element 15 and the inner gripping element 24, made in the form of separate dies with a notch 25 and an outer annular groove 26 in the middle part, in which a split spring ring 27 is placed for pressing them simultaneously to the conical piston 10 and the conical surface 6 cones 5 on the central core 4.

In the absence of capture of the end of the emergency pipe by the dies of the external and internal capturing element 15 and 24, respectively, information about this can be obtained at the wellhead due to a jump in the pressure of the working fluid. This is due to the movement of the conical piston 10 and the spacer sleeve 18 in the axial channel of the hollow body 1 below the location of the drainage holes 23. In this case, a hydraulic connection is formed between the annular cavity 11 and the cavity of the well and the discharge of the working fluid with a decrease in pressure in the axial channel of the flexible pipe string .

Upon receipt of such a signal, the device is removed to the surface.

The invention in comparison with the prototype and other known technical solutions has the following advantages:

- the possibility of high reliable capture of the end of the emergency pipe with the simultaneous commissioning of the internal and external exciting elements during the interaction of their ribbed surfaces with the pipe body along the perimeter;

- the ability to control the gripping force of the emergency pipe body by the exciting elements with a minimum pressure of the working fluid;

- the ability to accurately obtain information about the operation of the device in case of impracticability of capturing the end of the emergency pipe by the exciting elements;

- has small diametrical dimensions and can be used in the axial channel of tubing with an outer diameter of 73 mm with an inner diameter of 62 mm.

Literature

1. Basarygin, Yu.M. Repair of gas wells [Text] / Yu.M. Basarygin, P.P. Makarenko, V.D. Mavromati. - M .: Nedra Publishing House OJSC, 1998. - S. 206-208; 208-210.

2. Pat. 2352755 Russian Federation, IPC Е21В 31/20. The pipe head [Text] / R.A. Gasumov, G.T. Sazonov, V.A. Sukovitsyn et al .; Applicant and patent holder of OJSC SevKavNIPIgaz. - No. 2007139939/03; declared 10/29/2007; publ. 04/20/2009, bull. No. 11. (prototype).

3. A.S. 1032167 USSR, MKI ³ Е21В 31/18. External free tube [Text] / А.V. Chepovetsky, A.A. Domalchuk, E.S. Lebedev et al. (USSR). - No. 2796879 / 22-03; declared 07/13/79; publ. 07/30/83, Bull. No. 28.

Claims (1)

A device for extracting a long pipe containing a hollow body with an inner conical surface in the lower part, a sub, a central core with a cone at the lower end installed in the axial channel of the hollow body, external and internal gripping elements installed in the hollow body with the possibility of axial and radial movement , spacer sleeve, conical piston, spring-loaded annular piston with radial holes connecting the annular cavity between the annular and conical pistons with an axial channel sweeping core, characterized in that the hollow body is provided with drainage holes made under the conical piston, the external gripping element is made in the form of dies equipped with T-shaped protrusions and a spacer sleeve provided with mating T-shaped bores for the protrusions of the dies and an inner annular groove for the split a spring ring installed with the possibility of contact with the external gripping element, and the internal gripping element is made in the form of dies with an annular groove on the outer surface a spindle equipped with a split spring ring mounted with the possibility of simultaneously pressing the dies to the conical piston and to the conical surface of the cone on the central core.

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