阅读说明：本技术 一种分瓣式完井封隔器的回插机构 (Back-inserting mechanism of split type well completion packer ) 是由 张其平 高凤垒 张克成 刘严 于 2021-01-26 设计创作，主要内容包括：本发明涉及完井封隔器的结构技术领域,用于实现回插机构在气密封要求下的结构设计,消除管柱螺纹连接,具体涉及一种分瓣式完井封隔器的回插机构,包括镶嵌在中心管上的限位条,限位条一侧连接有棘爪套,另一侧连接有限位套,棘爪套与中心管之间设置有限位装置,限位套螺纹连接在中心管上并对限位条进行径向限位,限位条上套设弹性棘爪,限位套后侧的中心管上连接有密封组件,中心管的下端部连接有导鞋；该回插机构通过限位条、中心管、限位套的配合设置,解决了现有技术中中心管取消螺纹连接后,产品无法装配,无法实现气密封要求的问题。(The invention relates to the technical field of the structure of a well completion packer, which is used for realizing the structural design of a back-inserting mechanism under the requirement of air sealing and eliminating the threaded connection of a pipe column, in particular to a back-inserting mechanism of a split type well completion packer, which comprises a limiting strip embedded on a central pipe, wherein one side of the limiting strip is connected with a pawl sleeve, the other side of the limiting strip is connected with a limiting sleeve, a limiting device is arranged between the pawl sleeve and the central pipe, the limiting sleeve is in threaded connection with the central pipe and is used for radially limiting the limiting strip, an elastic pawl is sleeved on the limiting strip, a sealing component is connected on the central pipe at the rear side of the limiting; this back inserting mechanism sets up through the cooperation of spacing strip, center tube, stop collar, has solved among the prior art after the center tube cancellation threaded connection, and the unable assembly of product can't realize the problem of airtight requirement.)

1. The utility model provides a mechanism is inserted to separating lamella formula completion packer's returning, its characterized in that, is including inlaying spacing (3) on center tube (1), spacing (3) one side is connected with pawl cover (2), and the opposite side is connected with stop collar (5), be provided with stop device between pawl cover (2) and center tube (1), stop collar (5) threaded connection is on center tube (1) and radially spacing to spacing (3), elastic pawl (4) are established to the cover on spacing (3), be connected with seal assembly on center tube (1) of stop collar (5) rear side, the lower tip of center tube (1) is connected with guide shoe (8).

2. A back-plugging mechanism for a segmented completion packer according to claim 1, wherein said sealing assembly comprises a snap-fit protection ring (6) and a vulcanising seal (7).

3. A back-plugging mechanism for a segmented completion packer according to claim 2, wherein said sealing assembly comprises 3 stages, each stage of vulcanised seal (7) being separated by a protection ring (6).

4. The back-plugging mechanism of a split completion packer as claimed in claim 1, characterized in that the guide shoe (8) is provided with a conical surface structure.

5. The back-inserting mechanism of a split completion packer as claimed in claim 1, wherein the limiting device comprises a protrusion arranged on the ratchet sleeve (2), and the central tube (1) is provided with a groove matched with the protrusion for limiting.

6. A back-plugging mechanism of a split completion packer according to claim 5, characterized in that the number of the protrusions on the ratchet sleeve (2) is 16 and the number of the grooves on the central tube (1) is 8.

Technical Field

The invention relates to the technical field of well completion packer structures, in particular to a back-plugging mechanism of a split type well completion packer, which is used for realizing the structural design of the back-plugging mechanism under the requirement of air sealing and eliminating the threaded connection of a pipe column.

Background

A well completion packer refers to a downhole tool having an elastomeric sealing element whereby the annulus between the string of tubing and the wellbore and between the strings of tubing of various sizes is sealed off and the producing zone isolated to control production fluids and protect the casing. The packer is used for layering in an oil production process, an oil production channel is designed on the packer, and when setting, the piston sleeve moves upwards, and the oil production channel is opened; after the setting, the upper layer pressure acts on the balance piston to push the rubber cylinder upwards, so that the deblocking pin is prevented from shearing force; when the oil extraction channel is unsealed, the unsealing pin is cut off by the friction force between the rubber sleeve and the sleeve, and the piston sleeve moves downwards to close the oil extraction channel.

The existing production process requires that the tubular column has air sealing capability, but the back-plugging structure of the existing well completion packer has threaded connection, so that the requirement of air sealing cannot be met, and if the upper joint of the back-plugging structure and the central pipe are simply used as a whole, the pawl cannot be assembled.

Disclosure of Invention

To the problem that the sealing effect of the back-inserting mechanism of the well completion packer among the prior art is not good, this application has provided the back-inserting mechanism of split type well completion packer, should back-inserting mechanism through the cooperation setting of spacing strip, center tube, stop collar, has solved among the prior art after the center tube cancellation threaded connection, the unable assembly of product, the unable problem that realizes airtight requirement.

In order to achieve the purpose, the invention provides a back-inserting mechanism of a split-type well completion packer, which comprises a limiting strip embedded on a central tube, wherein one side of the limiting strip is connected with a pawl sleeve, the other side of the limiting strip is connected with a limiting sleeve, a limiting device is arranged between the pawl sleeve and the central tube, the limiting sleeve is in threaded connection with the central tube and radially limits the limiting strip, an elastic pawl is sleeved on the limiting strip, the central tube on the rear side of the limiting sleeve is connected with a sealing assembly, and the lower end part of the central tube is connected with a guide shoe.

The application principle of back inserting mechanism: through the axial displacement of spacing restriction pawl, spacing passes through the location effect of center tube and pawl cover, can transmit the moment of torsion that the packer was released to the pawl, uses the screw thread to be connected stop collar and center tube simultaneously, and the stop collar has spacing effect, can fix spacing on the center tube with the cooperation of pawl cover, and the seal assembly who connects on the center tube has further played sealed stable effect, and the effect that leads shoes that the tip set up under the center tube has the direction.

After the packer finishes setting, the left-handed thread of the tubular column and the pawl can be positively rotated by the back-inserting mechanism, the back-inserting mechanism is separated from the packer body, the tubular string is taken out of a well head and is brought into the next tubular string, the tubular string is guided by the guide shoe and enters the packer body, the shrinkage function of the pawl is utilized, the tubular column is pressed down, the pawl is connected with the packer, the sealing stability is kept by the vulcanization sealing element, and the back connection of the tubular column is finished.

Further, the seal assembly includes a snap-fit protector ring and a vulcanization seal.

Wherein the seal assembly comprises 3 stages, each stage being separated from the vulcanised seal by a guard ring.

This application sets up 3 grades of vulcanizes the sealing member on the center tube, vulcanizes through the protection ring separation between the sealing member at every level, has guaranteed the sealing stability when assembling.

Furthermore, a conical surface structure is arranged on the guide shoe.

This application makes the guide effect that the guide shoe played better through set up the conical surface structure on the guide shoe.

Furthermore, stop device is including setting up the arch on the pawl cover, be provided with on the center tube with protruding spacing recess of cooperation.

Wherein, 16 bulges are arranged on the pawl sleeve, and 8 grooves are arranged on the central tube.

This application is through setting up stop device between center tube and pawl cover, and sets up the spacing arch on the pawl cover into 16, and spacing recess on the center tube sets up to 8, can keep rotation angle in 11.25, realizes the effect that stop device accurately aligns.

In summary, compared with the prior art, the invention has the following beneficial effects:

(1) the back inserting mechanism solves the problem of poor sealing effect of the back inserting mechanism in the prior art through the matched arrangement of the limiting strip, the central pipe and the limiting sleeve, and improves the sealing performance of the back inserting mechanism in the using process;

(2) according to the sealing device, 3 stages of vulcanized sealing elements are arranged on the central pipe, and each stage of vulcanized sealing elements are separated through the protection ring, so that the sealing stability during assembly is ensured;

(3) the conical surface structure is arranged on the guide shoe, so that the guide shoe has a better guiding effect;

(4) this application is through setting up stop device between center tube and pawl cover, and sets up the spacing arch on the pawl cover into 16, and spacing recess on the center tube sets up to 8, can keep rotation angle in 11.25, realizes the effect that stop device accurately aligns.

Drawings

FIG. 1 is a schematic structural view of a back-plugging mechanism of a segmented completion packer of the present invention;

FIG. 2 is a cross-sectional view of a pawl sleeve in the back-out mechanism of a segmented completion packer of the present invention;

FIG. 3 is a cross-sectional view of the connection of the central tube and the ratchet sleeve in the back-in mechanism of a segmented completion packer of the present invention.

Labeled as: 1-central tube, 2-pawl sleeve, 3-limit strip, 4-pawl, 5-limit sleeve, 6-protection ring, 7-vulcanized sealing element and 8-guide shoe.

Detailed Description

All features disclosed in this specification may be combined in any combination, except features and/or steps that are mutually exclusive.

In order to make the technical solutions of the present invention better understood by those skilled in the art, the present invention will be further described in detail with reference to fig. 1 to 3 and specific examples.

Example 1

Referring to fig. 1-3, the back-inserting mechanism of the split-type well completion packer provided by the invention comprises a limiting strip 3 embedded on a central tube 1, wherein one side of the limiting strip 3 is connected with a pawl sleeve 2, the other side of the limiting strip is connected with a limiting sleeve 5, a limiting device is arranged between the pawl sleeve 2 and the central tube 1, the limiting sleeve 5 is in threaded connection with the central tube 1 and radially limits the limiting strip 3, an elastic pawl 4 is sleeved on the limiting strip 3, a sealing assembly is connected on the central tube 1 at the rear side of the limiting sleeve 5, and the lower end part of the central tube 1 is connected with a guide shoe 8.

The application principle of back inserting mechanism: through the axial displacement of spacing strip 3 restriction pawl 4, spacing strip 3 passes through the location effect of center tube 1 with pawl cover 2, can transmit the moment of torsion that the packer was released to pawl 4, use the screw thread to be connected stop collar 5 with center tube 1 simultaneously, stop collar 5 has spacing effect, can fix spacing strip 3 on center tube 1 with the cooperation of pawl cover 2, the seal assembly who connects on the center tube 1 has further played sealed stable effect, the effect that leads shoes 8 that the tip set up under the center tube 1 has the direction.

This back insertion mechanism accomplishes the setting back at the packer, and the left-handed screw thread of accessible positive spin tubular column and pawl 4 will return insertion mechanism and packer body separation, will take out the well head with the pipe string, brings the next pipe string into simultaneously, through leading 8 direction, gets into the packer body, utilizes the shrink function of pawl 4, pushes down the tubular column, is connected pawl 4 and packer, keeps seal stability through vulcanize sealing member 7, accomplishes the tieback of tubular column.

Example 2

Based on embodiment 1, with reference to fig. 1-3, the seal assembly of this embodiment comprises a snap-fitted protector ring 6 and a vulcanised seal 7.

Wherein the seal assembly comprises 3 stages, each stage being separated by a protector ring 6 between vulcanised seals 7.

This application sets up 3 grades of vulcanizes sealing member 7 on center tube 1, and through protection ring 6 separation between every grade of vulcanizes sealing member 7, sealing stability when having guaranteed the assembly.

Example 3

The guide shoe 8 of this embodiment is provided with a tapered surface structure based on embodiment 1, referring to fig. 1 to 3.

This application makes the guide effect that guide shoe 8 played better through set up the conical surface structure on guide shoe 8.

Example 4

Based on embodiment 1, referring to fig. 1-3, the limiting device of this embodiment includes a protrusion disposed on the ratchet sleeve 2, and the central tube 1 is provided with a groove for limiting the protrusion.

Wherein, 16 projections are arranged on the pawl sleeve 2, and 8 grooves are arranged on the central tube 1.

This application is through setting up stop device between center tube 1 and pawl cover 2, and sets up spacing arch on the pawl cover 2 to 16, and spacing recess on the center tube 1 sets up to 8, can keep rotation angle in 11.25, realizes the effect that stop device accuracy aligns.

The above-mentioned embodiments only express the specific embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present application. It should be noted that, for those skilled in the art, without departing from the technical idea of the present application, several changes and modifications can be made, which are all within the protection scope of the present application.