Bridge plug with self-sealing capability, and application and use method thereof

Abstract

The present application relates to a kind of bridge plug with self-sealing capability, including setting structure, bridge plug body and rupture disc structure, setting structure is arranged in the upper end of bridge plug body, and setting mechanism can move downward along the axial direction of bridge plug body, the bottom end of bridge plug body is equipped with rupture disc structure, and rupture disc structure realizes the self-sealing of bridge plug.The present application realizes bridge plug self-sealing and rapid unsealing, effectively solves the problems of wellbore plugging and rapid unsealing when production string is run in production, has the advantages of fast sealing establishment, unsealing, high sealing performance, convenient operation, safety, reliability and good economy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas field downhole tools, in particular to a bridge plug with self-sealing capability and its application and use method. BACKGROUND

[0002] The offshore tight oil, shale oil and other low-permeability reservoir resources have high reserves and great development potential, but the natural productivity is low, and it is necessary to realize effective and economic development through fracturing stimulation. The fracturing oil displacement-standby absorption integrated stimulation process, as a brand-new offshore low-permeability reservoir stimulation development technology, has the dual advantages of fracture creation and permeability increase and oil displacement capacity increase, can greatly improve the post-fracturing productivity, and has gradually become one of the key technologies for efficient stimulation and development of offshore low-permeability reservoirs in China.

[0003] The bridge plug, as a key wellbore isolation tool, is commonly used in staged fracturing of cased and completed horizontal wells, and its main working principle is that the bridge plug is pumped to the predetermined position by a cable and then set by a setting tool, and then each stage is sequentially fractured and modified by plugging. At present, the plugging after the bridge plug is set is realized by pumping plugging balls. However, in the process of fracturing oil displacement-standby absorption integrated stimulation, in order to fully achieve the stimulation effect of fracture creation and permeability increase and oil displacement capacity increase, a period of standby absorption is required after fracturing for oil displacement, and plugging needs to be established in the wellbore during the standby period. Under such conditions, the bridge plug cannot realize the wellbore plugging during the interval between the standby absorption and production string running after oil displacement.

[0004] Therefore, there is an urgent need for a bridge plug with self-sealing capability. SUMMARY

[0005] The purpose of the present application is to provide a bridge plug with self-sealing capability and its application and use method, so as to solve the problem of the inability to pump additional plugging balls to realize wellbore plugging in the background technology.

[0006] To achieve the above purpose, the present application adopts the following technical solutions:

[0007] In a first aspect, the present application provides a bridge plug with self-sealing capability, which comprises a setting structure, a bridge plug body and a rupture disc structure. The setting structure is arranged at the upper end of the bridge plug body, and the setting structure can move downward along the axial direction of the bridge plug body. The bottom end of the bridge plug body is provided with the rupture disc structure, and the rupture disc structure realizes the self-sealing of the bridge plug.

[0008] The bridge plug with self-sealing capability preferably comprises a center pipe, an upper slip, an upper cone, a sealing rubber sleeve, a lower cone, a lower slip and a reverse structure, an outer surface of the center pipe is in turn matched with the setting structure, the upper slip, the upper cone, the sealing rubber sleeve, the lower cone, the lower slip and the rupture disc structure from top to bottom, the setting structure, the upper slip, the upper cone, the sealing rubber sleeve, the lower cone and the lower slip can slide downward along the axial direction of the center pipe.

[0009] The upper end of the center pipe is fixed with the setting structure through a shear thread, the inner surface of the upper slip is in sliding contact with the outer surface of the upper cone, the inner surface of the lower slip is in sliding contact with the outer surface of the lower cone, the upper cone and the lower cone are connected with the center pipe through the reverse structure, so that the upper cone and the lower cone can be connected to slide downward along the outer surface of the center pipe, and the rupture disc structure is fixedly connected with the bottom of the center pipe through a connecting thread.

[0010] The bridge plug with self-sealing capability preferably comprises an upper outer reverse tooth, an upper inner reverse tooth, a lower outer reverse tooth and a lower inner reverse tooth, the lower end of the shear thread is provided with the upper outer reverse tooth, the inner surface of the upper cone is provided with the upper inner reverse tooth, the upper end of the connecting thread is provided with the lower outer reverse tooth, and the inner surface of the lower cone is provided with the lower inner reverse tooth.

[0011] The center pipe and the upper cone are connected through the upper outer reverse tooth and the upper inner reverse tooth, so that the upper cone can be connected to slide downward along the outer surface of the center pipe, and the center pipe and the lower cone are connected through the lower outer reverse tooth and the lower inner reverse tooth, so that the lower cone can be connected to slide downward along the outer surface of the center pipe.

[0012] The bridge plug with self-sealing capability preferably comprises that the outer surface of the upper slip and the outer surface of the lower slip are respectively provided with anchoring teeth in a ring shape.

[0013] The bridge plug with self-sealing capability preferably comprises that the anchoring teeth are provided with stress notches in a circumferential direction, and the stress notches are parallel to the axial direction of the center pipe.

[0014] The bridge plug with self-sealing capability preferably comprises that the rupture disc structure comprises a rupture disc and a base body, the top of the base body is fixedly connected with the bottom of the center pipe through the connecting thread, the inside of the base body is provided with the rupture disc, and the rupture disc is not in contact with the center pipe.

[0015] The rupture disc is preferably circular-arched, and the convex surface of the circular-arched disc faces the lower end of the base body.

[0016] The setting structure is preferably a setting push ring.

[0017] In a second aspect, the present application provides a bridge plug with self-sealing capability, which comprises the bridge plug with self-sealing capability, and is applied to wellbore sealing in the offshore pressure drive stage.

[0018] In a third aspect, the present application provides a method for using the bridge plug with self-sealing capability, which comprises the bridge plug with self-sealing capability, and specifically comprises the following steps:

[0019] The bridge plug is pumped along the wellbore to a predetermined position by a cable;

[0020] The setting tool is detonated by the cable to complete setting of the bridge plug;

[0021] The setting tool is separated from the bridge plug body, the setting structure is pulled out with the cable, and the bridge plug is released;

[0022] The rupture disc structure blocks the reservoir fluid from flowing back, and realizes self-sealing.

[0023] The present application has the following advantages due to the above technical solutions:

[0024] The present application realizes self-sealing and rapid releasing of the bridge plug, effectively solves the rapid releasing of the wellbore sealing and the production string during the production, and has the advantages of fast sealing establishment, fast releasing, high sealing performance, convenient operation, safety, reliability and economy.

[0025] The present application adopts the upper and lower slips structure to ensure the bidirectional pressure-bearing capacity of the bridge plug after setting, and improve the pressure-bearing sealing capacity and safety.

[0026] The rupture disc adopts a circular-arched structure, wherein the convex surface of the circular-arched disc faces the lower end of the base body and the formation fluid, improves the pressure-bearing capacity, the concave surface of the circular-arched disc faces the wellhead, is beneficial to the forward pressure breaking, and realizes rapid releasing to establish a channel.

[0027] The reverse stopping structure between the upper and lower cones and the central pipe effectively solves the rebound problem of the upper and lower slips when the slips are on the pipe wall, prevents the sealing rubber tube from being shrunk due to the rebound of the upper and lower slips, and ensures the anchoring stability of the upper and lower slips on the inner wall of the casing and the sealing integrity of the sealing rubber tube. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a structural schematic diagram of the present application;

[0029] Figure 2 is a structural schematic diagram of the upper slip;

[0030] Figure 3 is a use state diagram of the upper inner reverse tooth and the upper outer reverse tooth;

[0031] Figure 4 is a structural schematic diagram of the rupture disc structure.

[0032] In the figure:

[0033] 1, central tube; 2, setting push ring; 3, upper slip; 4, upper cone; 5, sealing rubber; 6, lower cone;

[0034] 7, lower slip; 8, base body; 9, shear thread; 10, upper inner reverse tooth; 11, upper outer reverse tooth;

[0035] 12, lower inner reverse tooth; 13, lower outer reverse tooth; 14, rupture disc; 15, connecting thread; 16, stress notch;

[0036] 17, anchoring tooth. DETAILED DESCRIPTION

[0037] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0038] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "upper end", "axial direction", "downward", "top", "bottom end" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the systems or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0039] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "arranged" and "connected" should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or integrally connected; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium, or can be the internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0040] The application provides a bridge plug with self-sealing capability, which comprises a setting structure, a bridge plug body and a rupture disc structure, the setting structure is arranged at the upper end of the bridge plug body and can move downward along the axial direction of the bridge plug body, the bottom end of the bridge plug body is provided with the rupture disc structure, and the rupture disc structure realizes self-sealing of the bridge plug.

[0041] The application realizes self-sealing and rapid unsealing of the bridge plug, effectively solves wellbore sealing during post-pressurization oil soaking and rapid unsealing when the production string is lowered into production, and has the advantages of fast sealing establishment, fast unsealing, high sealing performance, convenient operation, safety, reliability and good economy.

[0042] Embodiment 1

[0043] As shown in Figure 1 A bridge plug with self-sealing capability, which comprises a setting structure, a bridge plug body and a rupture disc structure, the setting structure is arranged at the upper end of the bridge plug body and can move downward along the axial direction of the bridge plug body, the bottom end of the bridge plug body is provided with the rupture disc structure, and the rupture disc structure realizes self-sealing of the bridge plug.

[0044] The setting structure is a setting push ring 2.

[0045] The bridge plug body comprises a central pipe 1, an upper slip 3, an upper cone 4, a sealing rubber sleeve 5, a lower cone 6, a lower slip 8 and a non-return structure, the outer surface of the central pipe 1 is sequentially matched with the setting push ring 2, the upper slip 3, the upper cone 4, the sealing rubber sleeve 5, the lower cone 6, the lower slip 3 and the rupture disc structure from top to bottom, and the setting push ring 2, the upper slip 3, the upper cone 4, the sealing rubber sleeve 5, the lower cone 6 and the lower slip 3 can slide downward along the axial direction of the central pipe 1.

[0046] Continuing to refer to Figure 1 The upper end of the central pipe 1 is fixed with the setting push ring 2 through a shear thread 9. When the setting push ring 2 rapidly pushes the bridge plug to complete setting under the action of explosion impact force, the reaction force formed causes the upper end of the central pipe 1 and the connection of the shear thread 9 of the setting tool to be axially tensioned, when the preset shear strength is reached, the shear thread is invalid, the setting tool is separated from the central pipe 1, and the setting push ring 2 is pulled out with the cable, and the releasing is completed.

[0047] Continuing to refer to Figure 1 The tapered end of the upper cone 4 is inserted into the upper slip 3, that is, the inner surface of the upper slip 3 is in sliding contact with the outer surface of the upper cone 4.

[0048] The tapered end of the lower cone 6 is inserted into the lower slip 8, that is, the inner surface of the lower slip 8 is in sliding contact with the outer surface of the lower cone 6.

[0049] Referring to Figure 2As shown, the outer surface of the upper slip 3 and the outer surface of the lower slip 8 are circumferentially provided with anchoring teeth 17.

[0050] The anchoring teeth 17 are circumferentially provided with stress notches 16, and the stress notches 16 are axially parallel to the central tube 1. The stress notches 16 facilitate the radial expansion of the upper slip 3 and the lower slip 8 relative to the central tube 1.

[0051] After the cable detonation setting tool, the upper cone 4 is quickly inserted and expanded, and the lower cone 6 is quickly inserted and expanded, so that the upper slip 3 and the lower slip 7 are radially expanded relative to the central tube 1, and the anchoring teeth 17 of the upper slip 3 and the lower slip 7 are clamped in the inner wall of the casing to complete anchoring.

[0052] Continuing to refer to Figure 1 As shown, the upper cone 4 and the lower cone 6 are connected to the central tube 1 through the said reverse structure, so that the upper cone 4 and the lower cone 6 can be connected to the outer surface of the central tube 1 in a downward one-way sliding manner.

[0053] Referring to Figure 3 As shown, the said reverse structure includes upper outer reverse teeth 11, upper inner reverse teeth 10, lower outer reverse teeth 13 and lower inner reverse teeth 12. The upper inner reverse teeth 10 and the upper outer reverse teeth 11 are intermeshed, and the lower inner reverse teeth 12 and the lower outer reverse teeth 13 are intermeshed to form the said reverse structure. The said reverse structure allows the upper cone 4 and the lower cone 6 to move axially downward in a one-way manner, preventing the upper slip 3, the lower slip 8 and the sealing rubber 5 from rebounding, and further ensuring the sealing integrity.

[0054] Among them, the structure of the upper outer reverse teeth 11 and the lower outer reverse teeth 13 is the same, and the structure of the upper inner reverse teeth 10 and the lower inner reverse teeth 12 is the same, so Figure 3 The working state of the said reverse structure is illustrated by taking the cooperation of the upper outer reverse teeth 11 and the upper inner reverse teeth 10 as an example.

[0055] Continuing to refer to Figure 1 And Figure 3 As shown, the lower end of the shear thread 9 is provided with the upper outer reverse teeth 11, the inner surface of the upper cone 4 is provided with the upper inner reverse teeth 10, the upper end of the connecting thread 15 is provided with the lower outer reverse teeth 13, and the inner surface of the lower cone 6 is provided with the lower inner reverse teeth 12.

[0056] The central tube 1 and the upper cone 4 are connected through the upper outer reverse teeth 11 and the upper inner reverse teeth 10, so that the upper cone 4 can be connected to the outer surface of the central tube 1 in a downward one-way sliding manner. The central tube 1 and the lower cone 6 are connected through the lower outer reverse teeth 13 and the lower inner reverse teeth 12, so that the lower cone 6 can be connected to the outer surface of the central tube 1 in a downward one-way sliding manner.

[0057] Referring to Figure 4As shown, the rupture disc structure includes a rupture disc 14 and a base body 8, the top of the base body 8 is fixedly connected with the bottom of the central pipe 1 through a connecting thread 15, the inside of the base body 8 is provided with the rupture disc 14, and the rupture disc 14 is not in contact with the central pipe 1.

[0058] The rupture disc 14 is a circular arch, and the convex surface of the circular arch faces the lower end of the base body 8.

[0059] For example, in the case of using before the well soaking begins after the fracturing operation is completed: when used, the base 8 of the rupture disc realizes self-sealing, the circular arch of the rupture disc 14 blocks the reservoir fluid from flowing out, and isolation and sealing in the wellbore during the well soaking period of the fractured section are realized; at the end of the well soaking stage, the production string is lowered while the circular arch of the rupture disc 14 is pressed to make it rupture and unblock, and the wellbore passage is quickly established to realize production.

[0060] Embodiment 2

[0061] An application of a bridge plug with self-sealing capability, including the bridge plug with self-sealing capability described in Embodiment 1, the bridge plug is applied to the wellbore sealing in the offshore pressure drive stage.

[0062] Embodiment 3

[0063] A method for using a bridge plug with self-sealing capability, the bridge plug with self-sealing capability described in Embodiment 1, the method for using specifically includes the following steps:

[0064] S1: pumping the bridge plug along the wellbore to a predetermined position through a cable;

[0065] S2: using the cable to detonate a setting tool to make the bridge plug complete setting;

[0066] S3: the setting tool is separated from the bridge plug body, the setting structure is pulled out with the cable, and the releasing is completed;

[0067] S4: the rupture disc structure blocks the reservoir fluid from flowing out, and realizes self-sealing.

[0068] In the step S1, the setting tool is connected with the central pipe 1 through the shear thread 9 on the upper end of the central pipe 1, and the central pipe 1, the setting push ring 2, the upper slip 3, the upper cone 4, the sealing rubber tube 5, the lower cone 6, the lower slip 7 and the rupture disc structure on the central pipe 1 are pumped along the wellbore to a predetermined position through the cable pumping mode.

[0069] The specific process of step S2 is as follows: the cable detonation setting tool is used to set the setting ring 2 to move rapidly along the central tube 1 under the action of explosive impact force, and to synchronously push the upper slips 3, the upper cone 4, the sealing rubber sleeve 5 and the lower cone 6 to move rapidly downwards; meanwhile, the upper cone 4 is rapidly inserted into and expanded to the upper slips 3, and the lower cone 6 is rapidly inserted into and expanded to the lower slips 7, so that the upper slips 3 and the lower slips 7 are radially expanded relative to the central tube 1, and the anchoring teeth 17 of the upper slips 3 and the lower slips 7 are clamped in the inner wall of the casing to complete anchoring; meanwhile, the sealing rubber sleeve 5 is axially extruded to expand to complete the casing setting inside; meanwhile, the upper inner reverse tooth 10 and the upper outer reverse tooth 11 are engaged to form a reverse structure, and the lower inner reverse tooth 12 and the lower outer reverse tooth 13 are engaged to form a reverse structure, so that the upper cone 4 and the lower cone 6 can only move axially downwards in one direction, preventing the upper slips 3, the lower slips 7 and the sealing rubber sleeve 5 from rebounding, and further ensuring the sealing integrity.

[0070] The specific process of step S3 is as follows: the setting ring 2 rapidly pushes the bridge plug to complete setting under the action of explosive impact force, and the reaction force formed makes the upper end of the central tube 1 axially tensioned at the connection of the shear thread 9 of the setting tool, when the preset shear strength is reached, the shear thread 9 is disabled, the setting tool is separated from the central tube 1, and the setting ring 2 is pulled out with the cable to complete the releasing.

[0071] The specific process of step S4 is as follows: after the releasing is completed, the fracturing ball does not need to be sent, and the self-sealing is realized by using the rupture disc 14, the circular-arch convex surface of the rupture disc 14 blocks the reservoir fluid from returning, and the isolation and sealing of the wellbore during the soaking period of the fractured section are realized.

[0072] In addition, when the unsealing is needed, step S5 is further included: the soaking stage is ended, the production string is run in, and the circular-arch concave surface of the rupture disc 14 is pressed to break and unseal, so that the wellbore channel is rapidly established to realize the production.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; although the foregoing embodiments of the present application have been described in detail, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A bridge plug with self-sealing capability, characterized in that, The bridge plug comprises a setting structure, a bridge plug body and a rupture disc structure, the setting structure is arranged at the upper end of the bridge plug body and can move downward along the axial direction of the bridge plug body, the bottom end of the bridge plug body is provided with the rupture disc structure, and the rupture disc structure realizes self-sealing of the bridge plug; The bridge plug body comprises a central pipe, an upper slip, an upper cone, a sealing rubber sleeve, a lower cone, a lower slip and a check structure, the outer surface of the central pipe is sequentially matched with the setting structure, the upper slip, the upper cone, the sealing rubber sleeve, the lower cone, the lower slip and the rupture disc structure from top to bottom, and the setting structure, the upper slip, the upper cone, the sealing rubber sleeve, the lower cone and the lower slip can slide downward along the axial direction of the central pipe in one direction; The upper end of the central pipe is fixed with the setting structure through a shear thread, the inner surface of the upper slip is in sliding contact with the outer surface of the upper cone, the inner surface of the lower slip is in sliding contact with the outer surface of the lower cone, the upper cone and the lower cone are connected with the central pipe through the check structure to realize that the upper cone and the lower cone can slide downward along the outer surface of the central pipe in one direction, and the rupture disc structure is fixedly connected with the bottom of the central pipe through a connecting thread; The rupture disc structure comprises a rupture disc and a base body, the top of the base body is fixedly connected with the bottom of the central pipe through the connecting thread, the inside of the base body is provided with the rupture disc, and the rupture disc is not in contact with the central pipe.

2. The bridge plug with self-plugging capability according to claim 1, characterized in that, The check structure comprises an upper outer check tooth, an upper inner check tooth, a lower outer check tooth and a lower inner check tooth, the lower end of the shear thread is provided with the upper outer check tooth, the inner surface of the upper cone is provided with the upper inner check tooth, the upper end of the connecting thread is provided with the lower outer check tooth, and the inner surface of the lower cone is provided with the lower inner check tooth; The central pipe and the upper cone are connected through the upper outer check tooth and the upper inner check tooth to realize that the upper cone slides downward along the outer surface of the central pipe in one direction, and the central pipe and the lower cone are connected through the lower outer check tooth and the lower inner check tooth to realize that the lower cone slides downward along the outer surface of the central pipe in one direction.

3. The bridge plug with self-sealing capability according to claim 2, characterized in that, The outer surface of the upper slip and the outer surface of the lower slip are respectively circumferentially provided with anchoring teeth.

4. The bridge plug with self-sealing capability according to claim 3, characterized in that, The anchoring teeth are provided with stress notches in the circumferential direction, and the stress notches are parallel to the axial direction of the central pipe.

5. The self-plugging bridge plug of claim 1, wherein, The rupture disc is circular-arched, and the convex surface of the circular-arched shape faces the lower end of the base body.

6. The bridge plug with self-sealing capability according to claim 5, wherein, The setting structure is a setting push ring.

7. The use of the bridge plug with self-sealing ability according to any one of claims 1 to 6, characterized in that, The bridge plug is applied to wellbore sealing in the offshore pressure drive stage.

8. The method of using the self-sealing bridge plug according to any one of claims 1 to 6, wherein, The method comprises the following steps: The bridge plug is pumped downward along the wellbore to a predetermined position through a cable; The setting tool is detonated by using the cable to make the bridge plug complete setting; The setting tool is separated from the bridge plug body, the setting structure is pulled out with the cable to complete the release; The rupture disc structure blocks the reservoir fluid from returning out to realize self-sealing.

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