RU191420U1 - Wellhead packer - Google Patents

Abstract

The utility model relates to the oil and gas industry and is a device for hermetically separating sections of a wellbore by pumping a working agent under pressure into an airtight cavity. An wellhead packer comprising a hollow body with two cuffs, hydraulically communicated overflow channels and located between the upper and lower movable stops, the upper of which is equipped with feed channels into the cavity of the upper cuff. The housing is made in the form of a hollow pipe with end technological threads. Cuffs are made in the form of toroidal chambers. The stops are fixed from falling out from above and below by the upper and lower lock nuts, screwed onto the corresponding end threads of the housing. The feed channel of the upper stop through the valve is in communication with the supply flexible hose. The upper stop is also equipped with a hooking mechanism for connecting to the flexible link of the elevator. The proposed wellhead packer is simple and reliable due to the use of cuffs made in the form of toroidal chambers, the pressure of which is maintained along a dedicated line - the hose. 1 ill.

Description

The utility model relates to the oil and gas industry and is a device for the tight separation of sections of a wellbore by pumping a working agent under pressure into an airtight cavity.

Known inflatable packer reusable (patent PM RU No. 167386, IPC ЕВВ 33/12, published on January 10, 2017 in Bull. No. 1) contains a barrel, at least one sleeve sleeve with a sealing element mounted on the barrel and fixed at both ends lids with the possibility of fixing the sleeve of the cuff by a split ring from moving up, the lower cover fixedly mounted on the barrel and the locking sleeve of the cuff from axial movements, the upper cover fixed to the barrel by connecting with the sleeve of the cuff and having the ability to move along b axis along the barrel, a sealing element fixed to the cuff sleeve at both ends and reinforced with two layers of steel plates arranged in a checkerboard pattern, fixed to both ends of the cuff sleeve in undercuts with steel rings and covering the entire perimeter of the reinforcement layer, the working annular cavity located between the barrel and the sealing element of the sleeve sleeve, a channel that allows the supply of working fluid under pressure into the working cavity, seals that seal the working cavity.

The disadvantages of this packer are the manufacturing complexity associated with the need for the presence of steel plates reinforced with two layers, and the connection of the cuff cavity with the borehole, at low injection pressures, the sealing of the space is unreliable.

Wellhead packer (patent RU No. 2112132, IPC ЕВВ 33/03, publ. 05/27/1998 in Bull. No. 15) containing a barrel with a lower stop for a sealing element placed on a sleeve with a top stop mounted with a clearance relative to the barrel, characterized in that the upper stop is made with a shank having cams with the ability to connect and disconnect with a column flange, while the upper end of the shank is sealed relative to the barrel and equipped with a handle for its circular rotation, and in the lower stop there is a radial channel communicating the gap between ox and stops with the annulus, and the shank above the cams is made with a radial channel and is equipped with a supply pipe.

The disadvantages of this packer are the complexity of manufacture and the large mass associated with the need for two coaxial metal pipes from the mouth to the installation interval, as well as the lack of protection against leakage of the sealing element (no duplication).

Wellhead packer (patent RU No. 2152506, IPC ЕВВ 33/12, publ. 07/10/2000 in Bull. No. 19), consisting of a housing, a seal assembly and a shank, characterized in that the seal assembly is made of two radial cuffs with collars and gentle external chamfers to enter the packer at the wellhead, separated by a washer with bevels, geometrically corresponding to the surface of the collar of the cuffs and provided with channels for supplying fluid from the upper cuff to the lower cuff, as well as a spacer sleeve to limit the degree of compression of the cuffs with stabilizer stops, the upper of which is sleep It is equipped with channels for supplying fluid from the annulus to the cavity of the upper cuff, while the shank is provided with an annular row of radial through holes with a thread for installing retaining screws that fix the shank in the annular groove of the housing.

The disadvantages of this packer are the connection between the cuff cavity and the borehole; at low pressures, the sealing of the space is unreliable, and at high pressures, pressure on the casing may be higher than permissible, as well as the lack of protection against cuff leakage (no duplication).

The technical task of the proposed utility model is to create a simple and reliable design of the wellhead packer through the use of cuffs made in the form of toroidal chambers, the pressure of which is maintained along a dedicated line.

The technical problem is solved by the wellhead packer, comprising a hollow body with two cuffs, hydraulically communicated overflow channels and located between the upper and lower movable stops, the upper of which is equipped with feed channels into the cavity of the upper cuff.

What is new is that the body is made in the form of a hollow pipe with end technological threads, the cuffs are made in the form of toroidal chambers, the stops are fixed from falling out from above and below by the upper and lower lock nuts screwed onto the corresponding end threads of the body, and the feed channel of the upper stop through the valve is in communication with the supply flexible hose, while the upper stop is also equipped with a hook mechanism for connecting to the flexible rod of the lift.

The drawing shows a diagram of the wellhead packer with an axial section.

The wellhead packer includes a hollow body 1 with two cuffs 2 and 3, hydraulically communicated overflow channels 4 and movable stops located between the upper 5 and lower 6, the top 5 of which is provided with feed channels 7 into the cavity of the upper cuff 2. Housing 1 is made in the form of a hollow pipe with end technological threads 8 and 9. Cuffs 2 and 3 are made in the form of toroidal chambers. The stops 5 and 6 are fixed from falling out of the upper 10 and lower 11, respectively, by locking nuts screwed onto the corresponding end threads 8 and 9 of the housing 1. The feed channel 7 of the upper stop 5 is connected to the supply flexible hose 13 through the valve 12. The upper stop is also equipped with hook mechanism 14 (eye, hook, collet lock, etc. are not shown) for connecting to the flexible link 15 of the lift (not shown).

Structural elements and technological connections that do not affect the performance of the packer are not shown in the drawing.

The packer works as follows.

Before the descent, the wellhead packer is brought into working position. For this, the lower nut 11 is screwed onto the casing 1 from the bottom by thread 9, then the lower stop 6 is put on the casing 1 from the top. Cuffs 2 and 3 are connected and communicated by the overflow channels 4, together with the upper stop 5 connected and communicated with the upper cuff 2 by the channel feed 7, placed on top of the lower stop 6 and fixed on the housing 1 with the upper nut 10 using thread 8. The distance between the stops 5 and 6 is regulated by the corresponding nuts 10 and 11 (the smaller the distance between the stops 5 and 6, the larger the borehole diameter can block the cuffs 2 and 3). A valve 12 and a hose 13 are connected to the supply channel 7, after which the packer is pressurized by injecting air or liquid into the cuffs 2 and 3 through the hose 13 and then closing the valve 12. If the pressure in the cuffs 2 and 3 does not drop, then the packer is ready after bleeding ( Relief) pressure in cuffs 2 and 3 to work. Before lowering into a well (not shown), a flexible rod 15 is attached to the hook mechanism 14, and devices (not shown) necessary for carrying out technological operations are attached to the process threads 8 and 9. For example, the load can be attached to the lower thread 9 of the housing 1 when the packer is lowered below the liquid level to reduce the buoyancy of the packer, plugs to cut off the under-packer space of the well from the over-packer space, etc .; a valve and a supply pipe can be connected to the upper thread 8 to pump excess pressure into the under-packer space, a discharge pipe to exhaust gas from the under-packer space, a plug to create excess pressure in the over-packer space, or the like.

After assembly, the packer on flexible rod 15 is lowered into the well in the installation interval. Gas is supplied via a wellhead pump (not shown) through a hose 13 through a supply channel 7 to the upper cuff 2, and from it through the flow channels 4 to the lower cuff 3. The cuffs 2 and 3 expand in the transverse direction, since in the longitudinal direction they are limited from expansion stops 5 and 6, and overlap the internal space of the wellhead. In the cuffs 2 and 3 through the hose 13 create a pressure increased relative to the well to reliably isolate the above-packer and under-packer spaces. The tightness of the wellhead packer is checked by adding liquid in a volume of 0.05 - 0.1 m ³ (depending on the diameter of the well) to the over packer space after it is installed in the interval of work. The pressure in the cuffs 2 and 3 is controlled by a wellhead pressure gauge (not shown). In the event of a pressure drop, it is supported regardless of the work being carried out in the over-packer and / or under-packer spaces of the well in cuffs 2 and 3 by pumping from the wellhead via a hose 13 with pressure control in order to eliminate a violation of the integrity of cuffs 2 and 3. Upon completion of technological work in the well the pressure in the cuffs 2 and 3 is vented through the hose 13, and the packer on the flexible rod 15 is removed from the well.

The proposed wellhead packer is simple and reliable in operation due to the use of cuffs made in the form of toroidal chambers, the pressure of which is maintained along a dedicated line — the hose.

Claims (1)

Wellhead packer, comprising a hollow body with two cuffs, hydraulically communicating flow channels and located between the upper and lower movable stops, the upper of which is provided with feed channels into the cavity of the upper cuff, characterized in that the casing is made in the form of a hollow pipe with end process threads, cuffs made in the form of toroidal chambers, the stops are fixed against falling out of the top and bottom, respectively, of the upper and lower lock nuts, screwed onto the corresponding end threads of the housing, and the feed channel of the upper stop through the valve is in communication with the supply flexible hose, while the upper stop is also equipped with a hook mechanism for connecting to the flexible rod of the lift.

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