阅读说明：本技术 胶塞和包含其的用于油管固井的碰压工具 (Rubber plug and impact tool containing same for oil pipe well cementation ) 是由 严焱诚 侯治民 房舟 崔警宇 郭治良 李腾飞 谭玮 李粒 张磊 于 2020-06-28 设计创作，主要内容包括：本发明提出了一种胶塞和包含其的用于油管固井的碰压工具,该胶塞包括胶塞芯,在从下到上方向上,胶塞芯具有依次固定连接的插入头、主体和连接尾,在插入头的外壁上设置有环形的安装槽；套设在连接尾的外壁上的皮碗；设置在安装槽处的用于限定胶塞的位置的第一锁定件,胶塞在下行到位后,其上的第一锁定件能与提前设置在油管的工作筒上的第二锁定件配合,从而锁定胶塞的位置,实现了有效避免水泥浆回流的目的,提高了油管固井质量。(The invention provides a rubber plug and a collision pressing tool containing the same for oil pipe well cementation, wherein the rubber plug comprises a rubber plug core, the rubber plug core is provided with an insertion head, a main body and a connection tail which are fixedly connected in sequence from bottom to top, and the outer wall of the insertion head is provided with an annular installation groove; the leather cup is sleeved on the outer wall of the connecting tail; the first locking piece that is used for injecing the position of plug that sets up in mounting groove department, the plug after the whereabouts targets in place, first locking piece on it can cooperate with the second locking piece that sets up in advance on oil pipe's working barrel to the position of locking plug has realized effectively avoiding the purpose of grout backward flow, has improved oil pipe well cementation quality.)

1. A rubber plug, comprising:

the rubber plug core is provided with an insertion head, a main body and a connection tail which are sequentially and fixedly connected in the direction from bottom to top, an annular mounting groove is arranged on the outer wall of the insertion head,

a leather cup sleeved on the outer wall of the connecting tail,

a first locking member disposed at the mounting groove for defining a position of the rubber plug.

2. The rubber plug according to claim 1, wherein the bottom wall of the mounting groove is configured as a first straight section, the lower wall surface of the mounting groove is configured as a first inclined section that increases the outer diameter of the insertion head in the up-down direction, and at the same time, the first locking member is configured as a C-shaped ratchet ring, the upper end of the inner wall surface of the C-shaped ratchet ring is configured as a first section that can be engaged with the first straight section, the lower end of the inner wall surface is configured as a second section that can be engaged with the first inclined section, and the upper end surface of the C-shaped ratchet ring can abut against the lower end surface of the main body.

3. The rubber plug according to claim 2 wherein the first beveled segment extends downwardly to connect with a second straight cylindrical segment at the lower end of which are disposed a second beveled segment and a lead-in segment in sequence, wherein the second beveled segment causes the outer diameter of the insertion head to gradually decrease in the up-down direction, and the lead-in segment is configured as a spherical segment.

4. The rubber plug according to any of claims 1 to 3 wherein a sealing groove for mounting a sealing ring is provided on the outer wall of the main body.

5. The rubber plug according to claim 4 wherein an upwardly facing first step surface is provided on the outer wall of the main body and a downwardly facing second step surface is provided on the outer wall of the main body, the second step surface being located below the first step surface, wherein the sealing groove is provided on the outer wall of the main body between the first step surface and the second step surface.

6. The plug as claimed in claim 5 wherein the angle between the first step surface and the axial direction is 130-140 degrees and the angle between the second step surface and the axial direction is 145-155 degrees.

7. The rubber plug according to any one of claims 1 to 6 wherein the upper end of the main body is provided with a transition section with a relatively increased outer diameter, and after the cup is sleeved at the connection tail, the outer diameter of the main body of the cup is the same as the outer diameter of the transition section.

8. The rubber plug according to claim 7 wherein the rubber plug core is of a unitary construction and the cup is disposed on the outer wall of the connection tail by vulcanization.

9. The plug according to any of claims 4 to 6 wherein a plurality of sealing grooves are axially spaced on the outer wall of the body.

10. A strike-in tool for tubing cementing, comprising:

the rubber plug according to any of the claims 1 to 9,

a working barrel which is communicated with the oil pipe, a second locking piece is arranged in the inner cavity of the working barrel,

when the rubber plug is thrown into the inner cavity of the oil pipe, the first locking piece can be matched with the second locking piece to limit the position of the rubber plug.

Technical Field

The invention belongs to the technical field of oil and gas well cementing, and particularly relates to a rubber plug and a collision pressing tool containing the rubber plug for oil pipe cementing.

Background

With the continuous development of the oil and gas exploration field to unconventional gas (dense gas, shale gas and coal bed gas), the facing objects are more and more complex, and the construction period is longer and longer.

After the well is conventionally built and drilled, an oil layer casing needs to be put in for well cementation operation, and then an oil pipe is put in for operations such as perforation, transformation, gas production and the like. The well construction method has long period and high cost. The integrated well construction technology can effectively overcome the problems, greatly reduce the well construction cost and improve the development benefit of oil and gas fields.

In the integrated well construction, oil pipes can be adopted for well cementation. In the existing oil pipe well cementation, a conventional rubber plug is often adopted for replacement operation. The problem that cement slurry flows backwards to influence the opening of the sliding sleeve after the rubber plug is replaced frequently occurs in the operation process.

Disclosure of Invention

Aiming at part or all of the technical problems in the prior art, the invention provides a rubber plug and a collision pressing tool for oil pipe cementing comprising the same. The rubber plug is matched with a working barrel of the oil pipe, and the position of the rubber plug is clamped and limited, so that cement slurry backflow is effectively avoided after grouting of well cementation cement slurry is completed, the well cementation quality of the oil pipe is improved, and the quality of a well shaft for subsequent well completion tools to be put into is guaranteed.

According to an aspect of the present invention, there is provided a rubber plug comprising:

the rubber plug core is provided with an insertion head, a main body and a connection tail which are sequentially and fixedly connected in the direction from bottom to top, the outer wall of the insertion head is provided with an annular installation groove,

a leather cup sleeved on the outer wall of the connecting tail,

the first locking piece is arranged at the installation groove and used for limiting the position of the rubber plug.

In one embodiment, the bottom wall of the mounting groove is configured as a first straight cylinder section, the lower wall surface of the mounting groove is configured as a first inclined surface section that the outer diameter of the insertion head increases in the up-down direction, meanwhile, the first locking member is configured as a C-shaped ratchet ring, the upper end of the inner wall surface of the C-shaped ratchet ring is configured as a first section that can be fitted with the first straight cylinder section, the lower end of the inner wall surface is configured as a second section that can be fitted with the first inclined surface section, and the upper end surface of the C-shaped ratchet ring can abut against the lower end surface of the main body.

In one embodiment, the first inclined surface section extends downward to be connected with a second straight cylinder section, and a second inclined surface section and a lead-in section are sequentially arranged at the lower end of the second straight cylinder section, wherein the second inclined surface section enables the outer diameter of the insertion head to be gradually reduced in the upper-to-lower direction, and the lead-in section is configured as a spherical section.

In one embodiment, a seal groove for mounting a seal ring is provided on the outer wall of the body.

In one embodiment, an upwardly facing first step surface is provided on the outer wall of the body, a downwardly facing second step surface is provided on the outer wall of the body, the second step surface being located below the first step surface, wherein the seal groove is provided on the outer wall of the body between the first step surface and the second step surface.

In one embodiment, the angle between the first step surface and the axial direction is 130-140 degrees, and the angle between the second step surface and the axial direction is 145-155 degrees.

In one embodiment, the upper end of the main body is provided with a transition section with the outer diameter size relatively increased, and after the leather cup is sleeved at the connection tail, the outer diameter of the main body of the leather cup is the same as that of the transition section.

In one embodiment, the plug core is of a unitary structure and the cup is disposed on the outer wall of the connection tail by vulcanization.

In one embodiment, a plurality of seal grooves are spaced axially on the outer wall of the body.

According to another aspect of the present invention, there is provided a strike-in tool for tubing cementing, comprising:

the rubber plug is arranged on the upper portion of the rubber plug,

a working barrel which is communicated with the oil pipe, a second locking piece is arranged in the inner cavity of the working barrel,

wherein, after the plug drops into in the oil pipe inner chamber, first locking piece can cooperate and the position of injecing the plug with the second locking piece.

Compared with the prior art, the invention has at least one of the following advantages that after the well cementation cement slurry is grouted, the rubber plug is put in, after the rubber plug is put in place, the first locking piece on the rubber plug can be matched with the second locking piece which is arranged on the working barrel of the oil pipe in advance, so that the position of the rubber plug is locked, the purpose of effectively avoiding cement slurry backflow is realized, the well cementation quality of the oil pipe is improved, and the quality of a well shaft which is put in by a subsequent well completion tool is ensured.

Drawings

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

figure 1 shows a plug according to one embodiment of the invention;

figure 2 shows a plug core according to one embodiment of the present invention;

FIG. 3 illustrates a first locking member according to one embodiment of the present invention;

figure 4 shows a mandrel according to one embodiment of the present 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.

Figure 1 shows a plug 100 according to the present invention. As shown in fig. 1, the plug 100 includes a plug core 1, a cup 2 and a first locking member 3. Wherein, the rubber plug core 1 is rod-shaped and can play the roles of a framework and a support. And, from the bottom up direction, the plug core 1 has an insertion head 11, a main body 12 and a connection tail 13 fixedly connected in sequence. An annular mounting groove 14 is provided on the outer wall of the insertion head 11. The packing cup 2 is sleeved on the outer wall of the connecting tail 13 and used for contacting with the inner wall of the oil pipe 200 to scrape off cement slurry in the displacement process. The first locking member 3 is disposed in the mounting groove 14. After the grouting of the well cementation cement slurry is completed, the rubber plug 100 is put into the oil pipe 200, the rubber plug 100 goes downwards and reaches the position of a working barrel 201 (shown in fig. 4), and the first locking part 3 can be in locking fit with a second locking part 202 arranged on the working barrel 201. Because the first locking member 3 is limited in the mounting groove 14, the rubber plug core 1 is fixed relative to the first locking member 3, so that the purpose of limiting the position of the rubber plug 100 is realized, cement slurry backflow is effectively avoided, the oil pipe well cementation quality is improved, and the quality of a well shaft for subsequently putting a well completion tool is ensured.

In one embodiment, as shown in FIG. 2, the bottom wall of the mounting slot 14 is configured as a first straight cylindrical section 15. The lower wall of the mounting groove 14 is configured as a first ramp section 16. In the top-to-bottom direction, the first slope section 16 causes the outer diameter of the insertion head 11 to gradually increase. Meanwhile, as shown in fig. 3, the first locking member 3 is configured as a C-type ratchet ring. The inner wall surface of the C-shaped ratchet ring is not on the same cylindrical surface, but the upper end is configured as a first straight cylindrical section 31 for mating with the first straight cylindrical section 15. The lower end of the inner wall surface of the C-shaped ratchet ring is configured as a second slope section 32 for cooperating with the first slope section 16. After being installed in place, the upper end surface of the C-shaped ratchet ring is abutted against the lower end surface of the main body 12. After the first locking member 3 is locked and matched with the second locking member 202, even if the rubber plug core 1 is pushed by upward cement slurry, the second section 3 is matched with the first inclined plane section 16 in an inclined plane, so that the C-shaped ratchet ring can be effectively prevented from falling off due to the close matching between the second section 3 and the first inclined plane section, and the clamping safety and the stability of the rubber plug 100 are ensured.

The first ramp section 16 extends downwardly to connect with the second straight section 17. A second inclined surface section 18 and a leading-in section 19 are sequentially arranged at the lower end of the second straight cylinder section 17. The second slope section 18 causes the outer diameter of the insertion head 11 to gradually decrease in the top-to-bottom direction. Preferably, the insertion section 19 is designed as a spherical section. The above arrangement maximizes the outer diameter dimension of insertion head 11 at the location of second straight section 17. That is, the insertion head 11 is configured in a substantially jujube-pit shape having a large middle outer diameter dimension and small outer diameter dimensions at both ends. The arrangement mode can ensure the stability of clamping locking, has good guidance, ensures the rubber plug 100 to be smoothly put in, and avoids clamping on any step surface of the pipe column.

A sealing groove 121 is formed in the outer wall of the main body 12 and used for installing a sealing ring 4 and achieving the function of well cementation sealing. This arrangement enables the sealing ring 4 to be arranged above the first locking element 3, the first locking element 3 not passing through the sealing groove 121 during assembly, not contacting the sealing ring 4, and not damaging the sealing surface. Preferably, an upwardly facing first step surface 122 is provided on the outer wall of the body 12. Meanwhile, a second step surface 123 facing downward is provided on the outer wall of the main body 12. The second step surface 123 is located below the first step surface 122, wherein the seal groove 121 is provided on the outer wall of the body 12 between the first step surface 122 and the second step surface 123. The arrangement is that the sealing groove 121 is arranged on a boss protruding in the radial direction of the main body 12, so that the outer diameter of the section below the second step surface 123 of the main body 12 is relatively reduced, and the running-in is facilitated; meanwhile, the axial dimension of the outer wall of the main body 12 between the first step surface 122 and the second step surface 123 is relatively small, and excessive wear of the seal ring 4 is avoided. Further preferably, the angle between the first step surface 122 and the axial direction is 130 degrees and 140 degrees, such as 135 degrees. And the angle formed by the second step surface and the axial direction is 145-155 degrees, such as 150 degrees.

Preferably, the upper end of the body 12 is provided with a transition section 124 of increased outer diameter dimension. When the leather cup 2 is sleeved on the connecting tail 13, the outer diameter of the main body 21 of the leather cup 2 is the same as that of the transition section 124. In addition, the rubber plug core 1 is of an integral structure. The leather cup 2 is arranged on the outer wall of the connecting tail 13 through vulcanization. The whole strength of the rubber plug core 1 can be guaranteed by the arrangement mode, no weak link exists, and the safety is improved. Meanwhile, the arrangement ensures the stable connection of the leather cup 2 and the rubber plug core 1, and ensures the displacement quality.

The C-shaped ratchet ring is made of 42CrMo alloy steel and is used for improving the pressure difference resistance of the C-shaped ratchet ring, so that the C-shaped ratchet ring with the design can be used in a well with more severe conditions and larger well cementation pressure difference, for example, the pressure difference reaches 60-70 MPa. In order to ensure the wear resistance and the temperature resistance of the leather cup 2, the leather cup is made of butyl rubber, fluororubber, natural rubber and the like. Of course, in the actual use process, the proportion of each component of the leather cup 2 can be properly adjusted according to the actual needs to meet the needs.

The application also relates to a bumping tool for cementing of the tubing. The impacting tool comprises the rubber plug 100 and a working barrel 201 connected to the oil pipe 200 in a communicating manner, as shown in fig. 4. A second locking member 202 is provided on the inner wall of the cylinder 201. The second locking member 202 is configured as a ratchet arranged on the inner wall of the working barrel 201 to form a snap lock with the C-shaped ratchet ring. After the plug 100 descends to the proper position, the first locking member 3 interacts with the second locking member 202 to define the position of the plug 100 and prevent the backflow of cement slurry.

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.