RU2428556C1 - Well swivel - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: well swivel consists of shank in form of shaft with through orifice, conic stop lug and thrust ring of antifriction material functioning as a friction bearing and a packing of the connection set in shank on one end, and external connecting thread on another end, case in form of bush with internal thread on one end and external thread on another end, thrust friction bearing made of antifriction material in form of shaped ring with internal surfaces interacting with shaft and case, nut with internal thread and conic thrust surface on internal recess for interaction with thrust ring and connection with case ready-fitted with thrust friction bearing and shank whereon there is installed thrust ring. Also, the nut is fixed against unscrewing with the case by means of lock screws and is packed with the shank and the case by means of packing rings.

EFFECT: reduced time for connection of equipment at wellhead, reduced number of emergencies and increased service life of equipment lowered into well, increased overhaul life of wells and, correspondingly, increased fluid output.

2 cl, 1 dwg

Description

The invention relates to the oil industry and can be used in the operation of oil wells, in particular in deviated and horizontal wells, as an articulation of pipes, downhole tools or downhole equipment in any combination to perform various technological tasks.

The closest in some design features to the proposed device are hinged sub, in particular a hinged sub, comprising a housing and a hollow shaft with a spherical support heel, equipped with contacting elements for transmitting torque, for example, teeth, spherical thrust bearings installed in the housing, a hollow rod with a seal (RF patent No. 2192535, CL ЕВВ 7/08, 2001).

These devices are used in drilling equipment and could be used as swivels and in the operation of oil wells, however, they have a complex structure and a slightly different purpose - they are designed for constant transmission of torque. The proposed device does not compete with the known devices described above and is intended to achieve other tasks.

There is a problem of connecting various equipment at the wellhead, which includes various production lines: cable lines, telemetry lines, gas pipes, hydraulic control pipelines, pipelines for the dosed supply of chemical reagents, and so on, with a production elevator, since the installation of downhole equipment to the pipe string on the wellhead is made by screwing pipes, couplings or sub with mating parts mounted equipment.

The objective of the invention is to expand the technological capabilities of the used articulated devices, the result of which is to ensure the convenience of docking at the mouth of various equipment, which includes various technological lines: cable lines, telemetry lines, gas pipes, hydraulic control pipelines, pipelines for the dosed supply of chemical reagents and other operational elevator, providing the necessary moment for making up the threaded joints during installation, ensuring the rigidity of installing packer-anchor equipment in the well, ensuring free control of the tool and tubing without puffs in the wellbore as a result of the passage of the tubing string and additional downhole equipment that is part of the production or technological elevator at intervals of intensive set of curvature and in the transitions of the inner diameter of the production string.

The problem is solved due to the fact that the downhole swivel

ACCORDING TO THE INVENTION:

- is equipped with a barrel in the form of a shaft with a through hole, a conical thrust protrusion with a thrust ring of antifriction material mounted on the barrel, which acts as a sliding bearing and seal joints at one end and an external connecting thread at the other end,

- a housing in the form of a sleeve with an internal thread at one end and an external thread at the other end,

- thrust sliding bearing made of antifriction material in the form of a figured ring with internal surfaces interacting with the barrel and the body,

- a nut with a female thread and a tapered thrust surface on the inner ledge to interact with the thrust ring and connect to the housing assembly with a thrust sliding bearing and barrel with a thrust ring mounted on it,

- the nut is fixed from unscrewing from the housing with locking screws and sealed with the barrel and the housing with o-rings,

- if necessary, the barrel can be fixed from axial rotation in any direction by installing some locking element, for example, a key installed in a keyway made on the barrel and a nut secured against falling out by a locking screw, and the key has sufficient strength characteristics to ensure that the torque is held the moment applied to the threaded connections of the tubing string, and not allowing multidirectional axial rotation of the barrel relative to all elements of the device.

The invention is illustrated in the drawing.

The borehole swivel shown in the drawing includes a bottom-up barrel 1, with a thrust ring 2, a thrust sliding bearing 3 and a housing 4, screwed by a nut 5, on one axis. The nut 5 is fixed from unscrewing from the housing 4 by the locking screws 6 and sealed with the barrel 1 and the housing 4 by a thrust sliding bearing 3 and the sealing rings 7. Depending on the technological tasks performed, the barrel 1 can be fixed from axial rotation by installing some locking element, for example keys 8, secured against falling out by the locking screw 9.

Downhole swivel works as follows.

Before docking at the wellhead, the swivel is screwed onto the barrel 1 with the upper coupling of the production lift tubing above the wellhead, after which the equipment is docked and screwed, which includes various production lines: cable lines, telemetry lines, gas pipes, hydraulic control pipelines, pipelines for dosed supply of chemicals and the like with the housing 4. Align the keyways on the nut 5 and barrel 1, install the key 8 and fix it against falling out with the locking screw 9, while ensures retention of torque applied to the threads of the tubing and not be multidirectional axial rotation of the barrel 1 with respect to all elements of the device.

If necessary, the downhole swivel can be mounted first to the descent equipment by docking and screwing the housing 4 with the lower part of the mounted equipment, and then mounted from the upper coupling of the production elevator column at the mouth by screwing the barrel 1 with it and installing the key 8 with screw 9.

Next, the equipment mounted with the borehole swivel is lowered, while the borehole swivel is below the mounted equipment and performs the function of a conventional pipe.

To ensure ease of installation of packer-anchor equipment in the well, as well as to ensure free control of the tool and tubing without puffs in the wellbore as a result of the passage of the tubing string and additional downhole equipment, which is part of the production or technological elevator through the intervals of intensive set of curvature and in the transitions of the internal the diameter of the production casing, the swivel is installed above the descent equipment without installing the dowel 8 and the locking screw 9. When mon the same downhole swivel first screw it over the barrel 1 with the upper coupling of the packer-anchor equipment, then screw the body 4 with the nipple thread of the upper pipe. If necessary, the installation of the downhole swivel can be carried out in the reverse order.

During the descent, an axial tensile load occurs, which is perceived by the thrust ring 2, while it provides additional tightness. The friction that occurs during the axial rotation of the barrel 1 is reduced by a thrust ring 2 made of antifriction material.

The compressive axial load that occurs when the production elevator is lifted is transferred to the thrust sliding bearing 3, ensuring the tightness of the joint and the reduction of friction arising during axial rotation.

During the STR and the operation of the equipment, the tightness between the barrel 1 and the nut 5, the housing 4 and the nut 5, as well as the housing 4 and the barrel 1 is provided by the sealing rings 7.

The positive effect of using a swivel in wells is to reduce the cost of docking equipment at the wellhead (excluding cable cutting and splicing, etc.), reduce the number of accidents and increase the service life of production equipment, increase the well overhaul period and, accordingly, increase fluid production.

Information sources

1. RF patent No. 2192535, cl. ЕВВ 7/08, 2001

Claims (2)

1. A borehole swivel, characterized in that it includes a barrel in the form of a shaft with a through hole, a conical thrust protrusion with a thrust ring of antifriction material mounted on the barrel, which serves as a sliding bearing and seal joints, at one end and an external connecting thread on the other end, in the form of a sleeve with an internal thread on one end and an external thread on the other end, a thrust sliding bearing made of antifriction material, in the form of a figured ring with an internal urenny surfaces interacting with the barrel and the housing, a nut with an internal thread and a tapered abutment surface on the inner ledge to interact with the thrust ring and connect to the housing assembly with a thrust sliding bearing and a barrel with a thrust ring mounted on it, and the nut is fixed from unscrewing with housing with locking screws and sealed with barrel and housing with o-rings. 2. The downhole swivel according to claim 1, characterized in that the barrel can be fixed from axial rotation in any direction by installing any locking element, for example a key installed in a keyway made on the barrel and a nut secured against falling out by the locking screw, moreover, the key has sufficient strength characteristics, ensuring retention of the torque applied to the threaded connections of the tubing string, and not allowing multidirectional axial rotation of the barrel relative to all elements tov device.

Images