CN111119783B

CN111119783B - Sealed cartridge device, cannula and tube string

Info

Publication number: CN111119783B
Application number: CN201811293592.5A
Authority: CN
Inventors: 岳慧; 伊伟锴; 段友智
Original assignee: China Petroleum and Chemical Corp; Sinopec Research Institute of Petroleum Engineering
Current assignee: China Petroleum and Chemical Corp; Sinopec Research Institute of Petroleum Engineering
Priority date: 2018-11-01
Filing date: 2018-11-01
Publication date: 2021-11-02
Anticipated expiration: 2038-11-01
Also published as: CN111119783A

Abstract

The invention provides a sealing barrel device, an insertion pipe and a pipe string, wherein the sealing barrel device comprises an outer barrel, an installation groove is formed in the inner wall of the middle section of the outer barrel, and a sealing barrel arranged in the installation groove, wherein the wall thickness of the sealing barrel is larger than the groove depth of the installation groove, the sealing barrel device can be preset in a shaft, the insertion pipe is inserted into the shaft to be matched with the insertion pipe in the well completion process, so that the sealing effect is achieved, the structure avoids using complex components such as a packer and the like, and the sealing process is very simple. Simultaneously, the sealing reliability of the sealing mode of this application is high, can avoid the problem of packing element high pressure seal inefficacy.

Description

Sealed cartridge device, cannula and tube string

Technical Field

The invention relates to the technical field of natural gas well and gas storage well completion, in particular to a sealing cylinder device, an insertion pipe and a pipe string.

Background

The gas storage wells require periodic injection and production of natural gas to achieve a smooth supply of natural gas. In the operation process of the gas storage, the injection and production string is required to be safe and reliable, and the integrity and reliability of a shaft are ensured.

At present, conventional gas well completion is often adopted for gas storage. And a packer is adopted to protect the oil sleeve annulus. However, the packer has a complex structure, failure possibility exists in the processes of well descending, setting, sealing and unsealing, and particularly, the sealing failure of the rubber sleeve is easy to occur under high pressure due to the large annular space of the oil sleeve, so that the integrity of the shaft is influenced.

Thus, there is a need to create a seal assembly to improve the reliability of the seal of a gas storage reservoir or gas well.

Disclosure of Invention

In view of some or all of the above technical problems in the prior art, the present invention provides a sealing cartridge device, an insertion tube and a tube string. The sealing barrel device can be preset in a well bore, and a running cannula is matched with the sealing barrel device in the well completion process to achieve the sealing effect. And the sealing cylinder device and the cannula have simple structures, which is beneficial to greatly simplifying the well completion process.

According to a first aspect of the present invention, there is provided a sealed cartridge device comprising:

an outer cylinder, an installation groove is arranged on the inner wall of the middle section of the outer cylinder,

a sealing cylinder arranged in the mounting groove,

wherein, the wall thickness of the sealing cylinder is greater than the groove depth of the mounting groove.

In one embodiment, the wall thickness dimension of the sealing cylinder is 5-8 mm greater than the groove depth dimension of the mounting groove.

In one embodiment, the sealing cylinder is made of a ceramic material.

In one embodiment, a flare is provided on the inner wall of the upper end of the sealing cylinder.

In one embodiment, the outer barrel is of a split structure and comprises a lower connector and an upper connector partially sleeved in an inner cavity of the lower connector, and a mounting groove is formed between the lower end face of the upper connector and a first step face arranged on the inner wall of the lower connector.

According to a second aspect of the present invention, there is provided a cannula cooperating with the sealing cartridge device described above, comprising:

a main body section which can be matched with the sealing cylinder,

a seal disposed on an outer wall of the main body segment.

In one embodiment, a plurality of seals are axially spaced on the outer wall of the main body segment.

According to a third aspect of the present invention, there is provided a completion string comprising:

a lower tubular string having the above-described cannula,

and the upper pipe column can be connected with the upper pipe column through an inserting sealing structure.

In one embodiment, the lower tubular string further comprises a screen below the cannulation.

In one embodiment, the upper end surface of the screen is located 10-20 meters below the lower edge of the perforated section of the wellbore after the well is run in place

Compared with the prior art, the sealing cylinder device has the advantages that the sealing cylinder device can be preset in a shaft, the inserting pipe is matched with the sealing cylinder device in the well completion process to achieve the sealing effect to seal the oil sleeve annulus, the structure avoids complex parts such as a packer and the like, and the sealing process is very simple. Simultaneously, the sealing reliability of the sealing mode of this application is high, can avoid the problem of packing element high pressure seal inefficacy.

Drawings

Preferred embodiments of the present invention will be described in detail below with reference to the attached drawing figures, wherein:

FIG. 1 shows a sealed cartridge device according to one embodiment of the invention;

FIG. 2 illustrates a sealing cartridge device engaged with a cannula according to one embodiment of the present invention;

FIG. 3 shows a tube string according to an embodiment of the invention;

in the drawings, like parts are provided with like reference numerals. The figures are not drawn to scale.

Detailed Description

The invention will be further explained with reference to the drawings.

Fig. 1 shows a sealed cartridge device 100 according to the invention. As shown in fig. 1, the seal cartridge device 100 includes an outer cartridge 1 and a seal cartridge 2. The upper end and the lower end of the outer cylinder 1 are connected with a sleeve of a gas well, and the inner diameter of the outer cylinder can be full-diameter with the sleeve. An installation groove 11 is provided on the inner wall of the middle section of the outer cylinder 1. The radial part of the sealing cylinder 2 is embedded in the mounting groove 11, and the upper end surface and the lower end surface of the sealing cylinder are respectively abutted with the upper end surface and the lower end surface of the mounting groove 11. The wall thickness of the sealing cylinder 2 is larger than the groove depth of the mounting groove 11. That is, after the sealing cylinder 2 is installed, its inner wall projects radially inward with respect to the inner wall of the casing.

The sealing cartridge device 100 is pre-installed in the wellbore, i.e. the sealing cartridge device 100 is set on casing and advanced into the wellbore. During completion, as shown in FIG. 2, the running cannula 200 is engaged to achieve a sealing effect. The structure avoids complex parts such as a packer and the like arranged on the tubular column in the prior art, and is very simple. Meanwhile, the structure does not need setting processes such as pressure building and the like, and the sealing process is simple and convenient. In addition, the sealing reliability of the sealing mode is high, and the problem that the high-pressure sealing of the rubber cylinder fails can be avoided, so that the sealing safety is improved.

Preferably, the wall thickness of the main body of the sealing cylinder 2 is 5-8 mm larger than the groove depth of the mounting groove 11. The minimum inner diameter of the sealing cylinder 2 is 10-16 mm smaller than the inner diameter of the sleeve by the arrangement. The arrangement mode can ensure the smooth passing of the well cementation rubber plug and does not influence the well cementation operation. Meanwhile, after the well cementation is finished, the setting mode can also ensure the descending of the perforating gun at the later stage, and the perforating effect cannot be influenced. In addition, the arrangement mode is the optimized result of the components such as the outer cylinder 1, the sealing cylinder 2 and the like, and not only can the self-strength of each component be ensured, but also good sealing effect can be ensured.

In one embodiment, the sealing cylinder 2 is made of a ceramic material. In the case of a side drilling operation or a casing repairing operation, a tool can be lowered to crush the seal cartridge 2 and enlarge the inner diameter of the seal cartridge 2 of the seal cartridge apparatus 100 to meet a special operation such as a tool lowering operation. The smooth proceeding of the subsequent operation can be ensured under special conditions through the arrangement. In addition, the surface hardness of the sealing cylinder 2 made of ceramics is high, the sealing cylinder is not easily scratched by an oil pipe or other tools, and good sealing matching in the later period can be ensured. The ceramic sealing cylinder 2 has a good high-temperature resistance effect, and helps to ensure the sealing effect. Of course, the present application is not limited to a sealing cylinder 2 of ceramic material, for example, the sealing cylinder 2 may also be made of other breakable materials such as glass.

In one embodiment, a flare 21 is provided on the inner wall of the upper end of the sealing cylinder 2. Preferably, the inner diameter of the sealing cylinder 2 at the uppermost end of the flare 21 is the same as the inner diameter of the outer cylinder 1 at the junction. The flare 21 makes the upper end body inner wall of the sealing cylinder 2 and the upper end inner wall of the outer cylinder 1 transition in a slope. The flaring 21 can guide the components such as the insertion pipe 200 to smoothly go in, and can avoid accidental breakage caused by the fact that the components such as the pipe string 300 which go in collide with the upper end face of the sealing cylinder 2. Therefore, the arrangement not only ensures the smooth implementation of the operation process, but also ensures the operation safety. Of course, it is further preferable that the lower end inner wall of the sealing cylinder 2 is also configured to have the same structure as the flaring 21, so that the lower end main body inner wall of the sealing cylinder 2 and the lower end inner wall of the outer cylinder 1 are in a transition with an inclined surface to ensure the use safety of the sealing cylinder 2.

In one embodiment, the outer tub 1 is constructed in a split structure. For example, the outer tube 1 includes an upper joint 12 and a lower joint 13. Wherein, the lower end part of the upper joint 12 is inserted and sleeved on the upper end of the lower joint 13. Meanwhile, a first step surface 14 is provided on the inner wall of the lower joint 13. The mounting groove 11 is formed between the lower end surface of the upper joint 13 and the first step surface 14. The sealing cylinder 2 is clamped between the lower end surface of the upper joint 13 and the first step surface 14. The arrangement mode is simple in structure and easy to realize.

In order to ensure the self-sealing performance of the seal cartridge device 100, the seal rings 3 are arranged between the upper joint 13 and the lower joint 13 and between the lower joint 13 and the seal cartridge 2. To improve the sealing effect, a plurality of axially spaced sealing rings 3 may optionally be provided.

The cannula 200 according to the present application is used to cooperate with the sealing cartridge device 100 to form a sealing structure that seals off the oil jacket annulus. Specifically, as shown in fig. 2, the cannula 200 includes a main body segment 201. A seal 202 is provided on the outer wall of the body section 201. After the cannula 200 is run into the wellbore, the body section 201 is mated with the sealing barrel 2 with the seal 202 disposed therebetween to form a sealing fit, as shown in FIG. 3. Preferably, the sealing member 202 is a rubber sealing ring, which is partially embedded in a groove 203 formed in the main body section 201. Axially, a plurality of spaced grooves 203 are provided in the outer wall of the main body section 201, and a seal 202 is matingly disposed within each groove 203. The cross-sectional area of the seal 202 gradually increases in the direction from bottom to top. That is, the cross-sectional area of the seal 202 at the lower end is larger than the cross-sectional area of the seal 202 at the upper end. The arrangement can improve the sealing effect, ensure the operation safety of the gas well and ensure the smooth descending of the insertion pipe 200 so as to be closely matched with the sealing cylinder device 100.

As shown in fig. 3, the present application also relates to a string 500, the string 500 including a lower tubular string 300 and an upper tubular string 400. The lower string 300 is run into the wellbore first and the upper string 400 is run into the wellbore later, both being connected by the stab seal 501. During production, the stab seal 501 may be disengaged and the upper string 400 lifted out of the wellbore.

The lower tubular string 300 includes a screen 301 and the insert 200 described above. The screen 301 is located below the cannula 200. After the lower tubular string 300 is run in, the sealing structure of the cannula 200 and the sealing cartridge device 100 is positioned above the perforated section to act as a seal. While the screen 301 is below the perforated section, the uppermost face of the screen 301 is preferably 10-20 meters below the lower edge of the perforated section. This arrangement allows the flow path to create a flow around the screen 301. In addition, in the maintenance process, when the upper pipe column 400 is lifted out of a shaft for killing, the structure avoids gas invasion and killing fluid loss caused by the gravity displacement of gas and liquid, ensures the safety of well control and prevents the stratum from being polluted.

The use of the tube string 500 is discussed in detail below with respect to fig. 1-3.

First, the seal cartridge assembly 100 is run into the well with the casing while cementing. The sealing cartridge arrangement 100 is lowered into position above the perforation section. Due to the self-structure arrangement of the sealing cylinder device 100, the operations of well cementation, perforation and the like are not influenced.

Then, after cementing and perforating operations, the lower string 300 is run in. The cannula 200 running with the lower string 300 forms a sealing fit with the sealing cartridge 2 of the sealing cartridge assembly 100, sealing off the oil jacket annulus. The screen 301 is located below the perforated section and the bottom of the tubing can support the bottom of the well.

Next, after the lower string 300 is released, the upper string 400 is lowered again, and the lower end of the upper string 400 and the upper end of the lower string 300 are sealed by the plug seal structure 501. So far, gas injection and production operations can be implemented.

When the upper string 400 needs to be replaced due to corrosion or loss, the well killing fluid is pushed from the inside of the tubing to kill the well, and because the screen 301 is located below the perforation section, the killing fluid will not leak upwards into the formation at the lowermost end, and the gas in the formation will not enter downwards into the lower string 300. Therefore, the structure can avoid gas invasion and well killing fluid loss caused by gravity replacement of gas and liquid, ensure the safety of well control and protect the reservoir from pollution. After the plug seal 501 is unsealed, the upper string 400 may be pulled out of the wellbore.

In this application, the terms "upper" and "lower" are used with reference to the orientation of the earth formation.

The above is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily make changes or variations within the technical scope of the present invention disclosed, and such changes or variations should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A completion string, comprising:

a sealing cartridge assembly predisposed on a cannula, said sealing cartridge assembly comprising:

an outer cylinder, wherein an installation groove is arranged on the inner wall of the middle section of the outer cylinder,

the sealing cylinder is arranged in the mounting groove and is made of ceramic materials, and the wall thickness of the sealing cylinder is greater than the groove depth of the mounting groove;

a lower string having a cannula cooperating with the sealing cylinder device, the cannula including a main body section insertable into and cooperating with the lumen of the sealing cylinder, and a seal disposed on an outer wall of the main body section; and

an upper tubular column connectable to the lower tubular column by a plug seal structure;

and the lower pipe column also comprises a screen pipe, the screen pipe is positioned below the insert pipe, and after the well is put in place, the upper end surface of the screen pipe is positioned 10-20 meters below the lower edge of the perforated section of the well bore.

2. The completion string of claim 1, wherein the wall thickness dimension of the sealing barrel is 5-8 mm greater than the groove depth dimension of the mounting groove.

3. A completion string according to claim 1 or 2, wherein a flare is provided on the inner wall of the upper end of the sealing cartridge.

4. The completion string according to claim 1, wherein the outer casing is a split structure and comprises a lower joint and an upper joint partially sleeved in an inner cavity of the lower joint, and the mounting groove is formed between a lower end surface of the upper joint and a first step surface arranged on an inner wall of the lower joint.

5. The completion string of claim 1, wherein a plurality of the seals are axially spaced on an outer wall of the body section.