RU2112132C1 - Collar packer - Google Patents

Abstract

FIELD: oil and gas industry. SUBSTANCE: invention refers to packing devices used to shut well clearance across well-head, for example, between conductor and shaft of packer. Collar packer includes packer, shaft with lower rest and bushing carrying sealing member. From above it is limited by upper rest with tail part having cams. Upper end of tail part is fitted with handle for round turn of it with reference to shaft. Bushing, rest and tail part are manufactured as one unit and are installed with clearance relative to shaft. Cams of tail part can engage and disengage string flange. Lower rest has radial conduit. It communicates clearance between shaft and rest with well clearance. Tail part above cams has radial conduit and is fitted with feeding branch pipe. EFFECT: simplified design of collar packer and protection of walls of casing string against high loads. 2 dwg

Description

 The invention relates to the oil and gas industry, namely the construction of oil and gas wells.

 Known wellhead packer [1], containing a barrel with a shoe mounted on it, a sealing element, dies, cones, a thrust ring and a rotary nut.

 Its disadvantage is the danger of jamming the packer barrel with a rubber sealing element when it is compressed, as well as with dies when it is removed from the jig, since the dies are able to move freely along the trunk.

 Also known is the wellhead packer [2], comprising a barrel with a lower stop for a sealing element placed on a sleeve with an upper stop mounted with a clearance relative to the barrel and a locking device.

 The disadvantage of this packer is the design complexity due to the presence of nodes and parts such as an anchor node, cone, spring, split pipe, shoe, etc.

 In addition, the action of axial and horizontal loads from the bursting force of the dies of the anchor, which in some cases may be higher than the strength characteristics of the casing leads to a violation of the integrity of the latter, which limits the use of the device.

 The aim of the invention is to simplify the design of the packer and the protection of the walls of the column from the action of high loads.

 This goal is achieved by the described wellhead packer containing a barrel with a lower stop for a sealing element placed on a sleeve with an upper stop installed with a clearance relative to the barrel.

 What is new is that the upper stop is made with a shank having cams with the ability to connect and disconnect with a column flange, the upper end of the shank is sealed relative to the barrel and equipped with a handle for its circular rotation, and a radial channel is made in the lower stop, communicating the gap between the barrel and the stops with annulus, and the shank above the cams is made with a radial channel and is equipped with a supply pipe.

 These distinguishing features of the packer, in our opinion, meet the criterion of "significant differences of the invention, since they are not identical and equivalent in comparison with similar features of known devices and allow you to get a new positive effect that is not characteristic of known devices of the same purpose.

 So, the implementation of the packer of this design can significantly simplify, eliminate anchoring node and a number of parts, including the locking device. As a result, it becomes possible to combine the sleeve on which the sealing element is installed with its upper stop and shank and complete them in one piece, which increases its performance and reliability, the design is simplified to a minimum.

 In addition, the claimed packer has expanded functionality. It allows, if necessary, to carry out direct or reverse flushing of the well, which is very important during repair work in the well.

 In FIG. 1 shows the proposed wellhead packer connected to the column flange of the well in a partial longitudinal section; figure 2 is a section aa in figure 1.

 The wellhead packer comprises a barrel 1 (Fig. 1) with a lower stop 2 for the sealing element 3. The latter is placed on the sleeve 4 with the upper stop 5. The lower stop 2, the sleeve 4 and the upper stop 5 are installed relative to the barrel with a gap 6. The upper stop 5 is made with a shank 7 having cams 8 and provided with a handle 9 for its circular rotation. The sleeve 4, the upper stop 5 with the shank 7 are made in one piece, i.e. represent one detail. Cams 8 are designed to connect and disconnect the shank 7 with the column flange 10 of the well type bayonet connection. For this, longitudinal grooves 11 (FIG. 2) and radial grooves 12 with organic stops 13 in the axial direction are made on the column flange with the possibility of interaction with the shank cams 8. The upper part of the barrel ends with a coupling 14 and the lower one with a connecting thread 15. In order to allow direct or reverse flushing of the well, the upper end of the liner is sealed with sealing rings 16 relative to the barrel and a radial channel 17 is made, equipped with a supply pipe 18 with a tap 19, in the lower stop it is made a radial channel 20, communicating the gap 6 with the annulus 21.

 Wellhead packer works as follows.

 The tackle system (the tackle system in Fig. 1 is not shown) it is lowered into the jig 22 and installed with the coupling 14 on the elevator (the elevator is also not shown in Fig. 2). Then, by turning the handle 9 of the shank of the upper stop 5, the cams 8 are aligned with the longitudinal grooves 11. Then, by feeding the packer down to the stop of the cams 8 against the radial groove 12 and turning the shank 7 with the handle, the cams are fixed. After this, a tension is created by the tackle system, at which the barrel 1 moves upward until the ledge of the lower stop 2 contacts the sleeve 4. The sealing element 3 is compressed and the annular space 21 is closed between the packer and the conductor 22. If necessary, release the tackle system under the elevator ears. With this position of the packer, the well is ready to be examined by pumping liquid into it under excessive pressure with pumps through a square rod or through the head with cementing units, closing valve 19. Direct or reverse flushing of the wellbore is carried out, after opening valve 19 or other technological operations.

 To remove the packer from the well, after the work is completed, the elevator is stretched with the hoist system and the bars are removed from under the elevator ears. Then lower the tackle system while the barrel 1, moving down, releases the sealing element, which returns to its original position. By turning the handle 9, the cams 8 are disengaged from the groove 12 of the column flange 10 and the packer is removed to the surface.

The technical and economic advantage of the invention is as follows:
- significantly simplifies the design of the packer; there is no need to use such assemblies and parts as an anchor assembly, locking device, cone, shoe, spring, etc .;
- eliminates the risk of violating the integrity of the wall of the casing pipe (conductor) from the bursting forces of the dies anchor node, because in the proposed packer anchor node is absent;
- provides ease of manufacture and operation;
-functional capabilities are expanded, a direct or reverse flushing operation of the well is provided if necessary, or other technological operations.

Claims (1)

 Wellhead packer 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, with the upper end 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 the barrel and the stops with the annulus, and the tail Ovik over cams formed with a radial channel and provided with a supply pipe.

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