阅读说明：本技术 一种微量橡胶密封式可溶桥塞 (Trace rubber sealed soluble bridge plug ) 是由 杨超 曾斌 杨敏 丁兵 陈霖 刘涛 于 2021-02-05 设计创作，主要内容包括：本发明公开了一种微量橡胶密封式可溶桥塞,包括由可溶材料制作而成的芯轴,所述芯轴上依次设有推力环、上卡瓦、锥体、下卡瓦、引鞋,所述锥体与所述芯轴之间设有单向锁定结构,所述单向锁定结构的锁定方向为沿芯轴轴向且远离引鞋方向,所述锥体包括第一锥面和第二锥面,所述上卡瓦靠近所述锥体的一端设有与所述第一锥面匹配的锥形面内表面一,所述下卡瓦靠近所述锥体的一端设有与所述第二锥面匹配的锥形内表面二,所述第二锥面上依次套设有胶环上保护环、胶环、胶环下保护环,所述胶环下保护环与所述下卡瓦的上端面相连,所述胶环的长度根据工况液体压强进行确定。本发明总体长度短,橡胶用量少,能够缩短桥塞溶解时间。(The invention discloses a trace rubber sealed soluble bridge plug, which comprises a mandrel made of soluble material, the mandrel is sequentially provided with a thrust ring, an upper slip, a cone, a lower slip and a guide shoe, a one-way locking structure is arranged between the cone and the mandrel, the locking direction of the one-way locking structure is along the axial direction of the mandrel and is far away from the direction of the guide shoe, the cone comprises a first conical surface and a second conical surface, one end of the upper slip close to the cone is provided with a first conical surface inner surface matched with the first conical surface, one end of the lower slip close to the cone is provided with a second conical inner surface matched with the second conical surface, the second conical surface is sequentially sleeved with an upper rubber ring protection ring, a rubber ring and a lower rubber ring protection ring, the lower rubber ring protection ring is connected with the upper end face of the lower slip, and the length of the rubber ring is determined according to the working condition liquid pressure. The invention has short overall length and less rubber consumption, and can shorten the dissolving time of the bridge plug.)

1. A micro-rubber sealed soluble bridge plug is characterized by comprising a core shaft made of soluble materials, the mandrel is sequentially provided with a thrust ring, an upper slip, a cone, a lower slip and a guide shoe, a one-way locking structure is arranged between the cone and the mandrel, the locking direction of the one-way locking structure is along the axial direction of the mandrel and is far away from the direction of the guide shoe, the cone comprises a first conical surface and a second conical surface, one end of the upper slip close to the cone is provided with a first conical surface inner surface matched with the first conical surface, one end of the lower slip close to the cone is provided with a second conical inner surface matched with the second conical surface, the second conical surface is sequentially sleeved with an upper rubber ring protection ring, a rubber ring and a lower rubber ring protection ring, the lower rubber ring protection ring is connected with the upper end face of the lower slip, and the length of the rubber ring is determined according to the working condition liquid pressure.

2. A trace rubber-sealing soluble bridge plug according to claim 1, wherein the length of said rubber ring is determined by the following formula:

in the formula: l is the length of the rubber ring, mm; p is liquid pressure, MPa; rho is the density of the rubber ring, g/cm³(ii) a S is the cross section area of the inner diameter of the sleeve pipe in mm²。

3. A trace rubber-sealing soluble bridge plug according to claim 1, wherein said rubber ring is made of rubber and single-crystal elemental material.

4. A trace amount of rubber-sealed soluble bridge plug as claimed in claim 3, wherein said single-crystal elemental material comprises 3-8% of the total mass of said rubber ring.

5. A trace amount of rubber sealed soluble bridge plug as claimed in claim 3, wherein said single crystal elemental material is graphene.

6. The trace rubber sealing type soluble bridge plug according to claim 1, wherein the protective ring on the rubber ring comprises a first protective ring and a second protective ring, the first protective ring is provided with a first opening, a first bulge is arranged on the lower surface of the first protective ring symmetrical to the first opening, a first flange is arranged in the center of the lower surface of the first protective ring, and the bulge height of the first flange is smaller than the bulge height of the first bulge and smaller than the thickness of the second protective ring; the second protection ring is provided with a second opening matched with the first protrusion, the upper surface of the second protection ring symmetrical to the second opening is provided with a second protrusion matched with the first opening, and the center of the upper surface of the second protection ring is provided with a first groove matched with the first flange.

7. A trace rubber sealing soluble bridge plug according to claim 6, wherein the height of said first protrusion is the thickness of said second protective ring and the height of said second protrusion is the thickness of said first protective ring.

8. The trace rubber sealing type soluble bridge plug according to claim 1, wherein the under-rubber-ring protection ring comprises a third protection ring and a fourth protection ring, a third opening is formed in the third protection ring, a third protrusion is formed on the lower surface of the third protection ring symmetrical to the third opening, a third flange is formed in the center of the lower surface of the third protection ring, and the height of the third flange is smaller than the height of the third protrusion and smaller than the thickness of the fourth protection ring; the fourth protection ring is provided with a fourth opening matched with the third protrusion, the upper surface of the fourth protection ring symmetrical to the fourth opening is provided with a fourth protrusion matched with the third opening, the lower surface of the fourth protection ring symmetrical to the fourth opening is provided with a fifth protrusion, the center of the upper surface of the fourth protection ring is provided with a second groove matched with the third flange, and the center of the lower surface of the fourth protection ring is provided with a fourth flange.

9. A trace rubber sealing soluble bridge plug according to claim 8, wherein the height of said third protrusion is the thickness of said fourth protective ring and the height of said fourth protrusion is the thickness of said third protective ring.

10. A trace rubber sealed soluble bridge plug according to claim 8, wherein the upper surface of the lower slip is provided with a third groove matching the fourth flange, and the width of the guide groove of the lower slip matches the width of the fifth protrusion.

Technical Field

The invention relates to the technical field of bridge plugs, in particular to a trace rubber sealed soluble bridge plug.

Background

The soluble bridge plug is a commonly used staged fracturing tool, and mainly comprises a mandrel, a slip anchoring system, a rubber cylinder sealing system and a guide shoe, wherein a cable or a continuous oil pipe is used for descending to a shaft casing design position, the rubber cylinder is extruded under the action of thrust or hydraulic pressure generated by gunpowder explosion, so that the rubber cylinder is compressed and expanded, and meanwhile, a cone is driven to move downwards, so that the slip is stressed and expanded to bite the casing. The rubber cylinder is further extruded and expanded and seals the whole casing, and the bridge plug is completely set. When the thrust reaches the shearing value of the releasing pin, the pin is sheared, and the bridge plug is released.

The soluble bridge plug consists of a soluble magnesium-aluminum alloy material and a soluble rubber cylinder, when the bridge plug is contacted with water, the magnesium-aluminum material and the water generate electrochemical reaction, so that the purpose of dissolution is achieved, and the soluble rubber cylinder can be degraded in high-temperature aqueous solution. But the dissolving performance of the soluble bridge plug is not ideal at present, the dissolving body is not completely dissolved, a large amount of residual insoluble substances are still remained, the dissolved substances are not easy to flow back, and the dissolving time is longer. Especially, the rubber cylinder has the dissolution only related to the temperature, is not greatly influenced by the mineralization degree, and is the most difficult soluble part of the soluble bridge plug.

Disclosure of Invention

In view of the above problems, the present invention aims to provide a trace rubber seal type soluble bridge plug capable of improving the solubility of the bridge plug.

The technical scheme of the invention is as follows:

a micro-rubber sealed soluble bridge plug comprises a mandrel made of soluble materials, wherein a thrust ring, an upper slip, a cone, a lower slip and a guide shoe are sequentially arranged on the mandrel, a one-way locking structure is arranged between the cone and the mandrel, the locking direction of the one-way locking structure is along the axial direction of the mandrel and is far away from the direction of the guide shoe, the cone comprises a first conical surface and a second conical surface, one end of the upper slip close to the cone is provided with a first conical surface inner surface matched with the first conical surface, one end of the lower slip close to the cone is provided with a second conical inner surface matched with the second conical surface, the second conical surface is sequentially sleeved with an upper rubber ring protection ring, a rubber ring and a lower rubber ring protection ring, the lower rubber ring protection ring is connected with the upper end face of the lower slip, and the length of the rubber ring is determined according to the working condition liquid pressure.

Preferably, the length of the glue ring is determined by the following formula:

in the formula: l is the length of the rubber ring, mm; p is liquid pressure, MPa; rho is the density of the rubber ring, g/cm³(ii) a S is the cross section area of the inner diameter of the sleeve pipe in mm²。

Preferably, the rubber ring is made of rubber and single-crystal elementary materials.

Preferably, the single-crystal elementary substance material accounts for 3-8% of the total mass of the rubber ring.

Preferably, the single-crystal elementary substance material is graphene.

Preferably, the protective ring on the rubber ring comprises a first protective ring and a second protective ring, the first protective ring is provided with a first opening, a first protrusion is arranged on the lower surface of the first protective ring which is symmetrical to the first opening, a first flange is arranged at the center of the lower surface of the first protective ring, and the protrusion height of the first flange is smaller than the protrusion height of the first protrusion and smaller than the thickness of the second protective ring; the second protection ring is provided with a second opening matched with the first protrusion, the upper surface of the second protection ring symmetrical to the second opening is provided with a second protrusion matched with the first opening, and the center of the upper surface of the second protection ring is provided with a first groove matched with the first flange.

Preferably, the height of the first protrusion is the thickness of the second protection ring, and the height of the second protrusion is the thickness of the first protection ring.

Preferably, the rubber under-ring protection ring comprises a third protection ring and a fourth protection ring, the third protection ring is provided with a third opening, a third protrusion is arranged on the lower surface of the third protection ring which is symmetrical to the third opening, a third flange is arranged at the center of the lower surface of the third protection ring, and the height of the third flange is smaller than the height of the third protrusion and smaller than the thickness of the fourth protection ring; the fourth protection ring is provided with a fourth opening matched with the third protrusion, the upper surface of the fourth protection ring symmetrical to the fourth opening is provided with a fourth protrusion matched with the third opening, the lower surface of the fourth protection ring symmetrical to the fourth opening is provided with a fifth protrusion, the center of the upper surface of the fourth protection ring is provided with a second groove matched with the third flange, and the center of the lower surface of the fourth protection ring is provided with a fourth flange.

Preferably, the height of the third protrusion is the thickness of the fourth protection ring, and the height of the fourth protrusion is the thickness of the third protection ring.

Preferably, the upper surface of the lower slip is provided with a third groove matched with the fourth flange, and the width of the guide groove of the lower slip is matched with the width of the fifth bulge.

The invention has the beneficial effects that:

compared with the existing bridge plug, the total length and the total mass of the bridge plug are both reduced, and in addition, rubber is replaced by the rubber ring in the prior art, and the length and the mass of the bridge plug are both reduced, so that the dissolution time of the bridge plug is shortened, the proportion of insoluble substances is reduced, and the dissolution performance is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic structural view of a trace rubber seal type soluble bridge plug of the present invention;

FIG. 2 is a schematic cross-sectional view of a micro-rubber sealing type soluble bridge plug according to the present invention;

FIG. 3 is a schematic view of the lower surface of the first protection ring of the protection ring on the trace rubber sealing type soluble bridge plug rubber ring of the present invention;

FIG. 4 is a schematic top surface view of a second protection ring on the micro rubber sealing type soluble bridge plug rubber ring of the present invention;

FIG. 5 is a schematic view of the lower surface of the third protection ring of the lower protection ring of the micro-rubber sealing type soluble bridge plug rubber ring of the present invention;

FIG. 6 is a schematic top surface view of a fourth protection ring of the lower protection ring of the micro rubber sealing type soluble bridge plug rubber ring of the present invention;

FIG. 7 is a schematic view of the lower surface of the fourth protection ring of the lower protection ring of the micro-rubber sealing type soluble bridge plug rubber ring of the present invention;

FIG. 8 is a schematic structural view of an embodiment of a micro-rubber sealed soluble bridge plug lower slip of the present invention;

fig. 9 is a structural schematic diagram of an embodiment of the micro-rubber sealing type soluble bridge plug one-way locking structure of the invention.

Reference numbers in the figures: 1-mandrel, 2-thrust ring, 3-upper slip, 4-cone, 5-rubber ring upper protection ring, 510-first protection ring, 511-first opening, 512-first projection, 513-first flange 520-second protection ring, 521-second opening, 522-second projection, 523-first groove, 6-rubber ring, 7-rubber ring lower protection ring, 730-third protection ring, 731-third opening, 732-third protrusion, 733-third flange, 740-fourth protection ring, 741-fourth opening, 742-fourth protrusion, 743-fifth protrusion, 744-second groove, 745-fourth flange, 8-lower slip, 801-third groove, 802-guide groove, 9-guide shoe, 10-unidirectional locking structure.

Detailed Description

The invention is further illustrated with reference to the following figures and examples.

It should be noted that, in the present application, the embodiments and the technical features of the embodiments may be combined with each other without conflict.

It is noted that, unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

In the present invention, the terms "first", "second", and the like are used for distinguishing similar objects, but not for describing a particular order or sequence order, unless otherwise specified. It is to be understood that the terms so used; the terms "upper", "lower", "left", "right", and the like are used generally with respect to the orientation shown in the drawings, or with respect to the component itself in a vertical, or gravitational orientation; likewise, "inner", "outer", and the like refer to the inner and outer relative to the contours of the components themselves for ease of understanding and description. The above directional terms are not intended to limit the present invention.

As shown in fig. 1-9, the invention provides a micro-rubber sealed soluble bridge plug, which comprises a mandrel 1 made of a soluble material, wherein the mandrel 1 is sequentially provided with a thrust ring 2, an upper slip 3, a cone 4, a lower slip 8 and a guide shoe 9, a one-way locking structure 10 is arranged between the cone 4 and the mandrel 1, the locking direction of the one-way locking structure 10 is along the axial direction of the mandrel 1 and is far away from the guide shoe 9, the cone 4 comprises a first conical surface and a second conical surface, one end of the upper slip 3 close to the cone 4 is provided with a first conical surface inner surface matched with the first conical surface, one end of the lower slip 8 close to the cone 4 is provided with a second conical surface matched with the second conical surface, the second conical surface is sequentially sleeved with an upper rubber ring protection ring 5, a rubber ring 6 and a lower rubber ring protection ring 7, and the lower rubber ring protection ring 7 is connected with the upper end surface of the lower slip 8, the length of the rubber ring 6 is determined according to the working condition liquid pressure.

The sealing principle of the rubber ring is as follows: the staged fracturing setting tool applies certain pressure to push the thrust ring 2, and the cone 4 moves downwards along with the continuous increase of the pressure to open the upper protective ring 5, the rubber ring 6, the lower protective ring 7 and the lower slip 8 of the rubber ring, so that the rubber ring 6 is tightly attached to the inner wall of the sleeve to realize sealing. The rubber ring upper protection ring 5 and the rubber ring lower protection ring 7 can enable rubber to run off less, and the sealing effect can be achieved by using less rubber.

In a particular embodiment, the length of the glue ring 6 is determined in particular by the following formula:

in the formula: l is the length of the rubber ring, mm; p is liquid pressure, MPa; rho is the density of the rubber ring, g/cm³(ii) a S is the cross section area of the inner diameter of the sleeve pipe in mm²。

The cross section area of the inner diameter of the sleeve is the cross section area of the rubber ring during sealing; in the embodiment, the length of the rubber ring is the minimum value of L, namely L_minL/ρ S. It should be noted that the closer the length L of the rubber ring is to L_minThe smaller the amount of the colloidal ring, the shorter the dissolution time, although L may be larger than L_minThe length of the specific rubber ring can be determined according to the requirement of dissolution time.

In a specific embodiment, the rubber ring 6 is made of rubber and a single-crystal elementary material, wherein the single-crystal elementary material accounts for 3-8% of the total mass of the rubber ring 6. Optionally, the single-crystal elemental material is sheet graphene.

In a specific embodiment, the graphene flakes account for 5% of the total mass of the rubber ring 6, and the rubber ring performance test results in this embodiment are shown in table 1:

TABLE 1 test results of performance of rubber ring

Performance of	Pure rubber	Ring rubber of the embodiment (rubber + 5% graphene)	Rate of increase
				Elongation (%)	267	317	18.73％
Mechanical force (MPa)	22.7	24.8	9.25％
				Elasticity (cm)	5.5	11.1	101.82％
Dissolution time (sky)	10	7	30.00％

According to the performance test results in table 1, the elongation, mechanical force, elasticity, solubility and the like of the rubber ring added with graphene are all improved, and the problem that rubber is insoluble in the prior art can be effectively solved.

In a specific embodiment, the protective ring 5 on the rubber ring comprises a first protective ring 510 and a second protective ring 520, the first protective ring 510 is provided with a first opening 511, a first protrusion 512 is provided on the lower surface of the first protective ring 510 symmetrical to the first opening 511, a first flange 513 is provided at the center of the lower surface of the first protective ring 510, and the protrusion height of the first flange 513 is smaller than the protrusion height of the first protrusion 512 and smaller than the thickness of the second protective ring 520; the second protection ring 520 is provided with a second opening 521 matched with the first protrusion 512, the upper surface of the second protection ring 520 symmetrical to the second opening 521 is provided with a second protrusion 522 matched with the first opening 511, and the center of the upper surface of the second protection ring 520 is provided with a first groove 523 matched with the first flange 513.

The rubber under-ring protection ring 7 comprises a third protection ring 730 and a fourth protection ring 740, wherein a third opening 731 is arranged on the third protection ring 730, a third protrusion 732 is arranged on the lower surface of the third protection ring 730 which is symmetrical to the third opening 731, a third flange 733 is arranged at the center of the lower surface of the third protection ring 730, and the height of the third flange 733 is smaller than that of the third protrusion 732 and smaller than that of the fourth protection ring 740; a fourth opening 741 matched with the third protrusion 732 is disposed on the fourth protection ring 740, a fourth protrusion 742 matched with the third opening 731 is disposed on an upper surface of the fourth protection ring 740 symmetrical to the fourth opening 741, a fifth protrusion 743 is disposed on a lower surface of the fourth protection ring 740 symmetrical to the fourth opening 741, a second groove 744 matched with the third flange 733 is disposed at a center of the upper surface of the fourth protection ring 740, and a fourth flange 745 is disposed at a center of the lower surface of the fourth protection ring 740.

Optionally, the height of the first protrusion 512 is the thickness of the second protection ring 520, and the height of the second protrusion 522 is the thickness of the first protection ring 510. The height of the third protrusion 732 is the thickness of the fourth protection ring 740, and the height of the fourth protrusion 742 is the thickness of the third protection ring 730.

Optionally, the thicknesses of the first guard ring 510, the second guard ring 520, the third guard ring 730, and the fourth guard ring 740 are all the same.

Optionally, the first opening 511 and the third protrusion 732 are on the same axis.

In a specific embodiment, the upper surface of the lower slip 8 is provided with a third groove 801 matching the fourth flange 745, and the width of the guide groove 802 of the lower slip 8 matches the width of the fifth protrusion 743.

In a specific embodiment, the upper slip 3 and the lower slip 8 are both of an integral structure and are divided into 8 pieces on the integral structure, three slip teeth (not shown) are uniformly distributed on each piece of the upper slip 3, and 4 slip teeth are uniformly distributed on each piece of the lower slip 8. Optionally, the outer surface of the slip tooth is coated with a hard coating, and cylindrical alloy particles or cylindrical ceramic particles are adopted as the upper slip tooth and the lower slip tooth.

In a specific embodiment, the outer surface of the guide shoe 9 is provided with a plurality of wear-proof teeth (not shown), the wear-proof teeth are uniformly distributed in the radial direction of the guide shoe 9 to form a double row, and the wear-proof teeth of the double row are distributed in a staggered manner.

In a specific embodiment, the one-way locking structure 10 comprises a lock ring between the cone 4 and the mandrel 1, and the contact surface of the lock ring and the cone 4 is provided with mutually matched latch teeth.

In a specific embodiment, a rubber sealing ring (not shown) is arranged between the cone 4 and the mandrel 1, and optionally, two rubber sealing rings are arranged. The rubber sealing ring can enable the cone 4 and the mandrel 1 to be tightly attached and sealed, and prevent water solution from leaking from the inner wall of the sleeve and the surface of the mandrel after setting.

In a specific embodiment, the first tapered surface and the second tapered surface of the cone 4 share the same end surface. In another specific embodiment, the lower surface of the first conical surface of the cone 4 is connected to the upper end surface of the column, and the upper surface of the second conical surface is connected to the lower end surface of the column.

In a specific embodiment, the overall length of the micro-rubber sealed soluble bridge plug is 360.1mm, the overall mass is 3300g, the inner diameter of the mandrel 1 is 35mm, the outer diameter is 48mm, the outer diameter of the top is 70mm, and the length is 327.6 mm; the outer diameter of the thrust ring 2 is 98 mm; the outer diameter of the upper slip 3 is 92mm, and the length is 51 mm; the maximum outer diameter of the cone 4 is 98mm, and the length is 141.7 mm; the outer diameter of the lower slip 8 is 92mm, and the length of the lower slip is 85 mm; the smaller end of the guide shoe 9 is 63.4mm in outer diameter, and the larger end is 98 mm; the rubber ring 6 has a length of 14mm and a mass of 50 g. The setting and hand-losing force of the bridge plug is 10-15t, the sealing pressure resistance of the rubber ring is 70MPa, and 24 (7mm) ceramic particles are arranged. The dissolution time of the bridge plug body is 3 days, the dissolution time of the rubber ring is 6 days, and the proportion of insoluble substances is less than 1 percent. Compared with the prior art, the bridge plug has the advantages that the dissolving time of the bridge plug body is 8-10 days, the dissolving time of the rubber cylinder is 10-12 days, the proportion of insoluble substances is 2%, the dissolving performance of the bridge plug is integrally improved by more than 50%, and the bridge plug has remarkable progress compared with the prior art.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.