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CN-121993094-A - Directional controllable full-soluble bridge plug and application method thereof

CN121993094ACN 121993094 ACN121993094 ACN 121993094ACN-121993094-A

Abstract

The bridge plug comprises a central tube, a seat sealing assembly and a sealing rod, wherein the seat sealing assembly is in sealing connection with the outer peripheral surface of the central tube, the sealing rod is in sealing connection with the inner peripheral surface of the central tube, the seat sealing assembly comprises a rubber sleeve and a slip push sleeve, the central tube and the seat sealing assembly are made of soluble materials, the central tube is only provided with a dissolution blocking layer in other outer surface areas except the inner peripheral surface which is in connection with the sealing rod, the slip push sleeve is only provided with a dissolution blocking layer in other outer surface areas except the inner peripheral surface which is in connection with the central tube, and the sealing rod can be separated from the central tube so as to allow the central tube and the seat sealing assembly to be directionally dissolved from inside to outside. Through the technical scheme, through carrying out the dissolution resistant treatment to each part, the bridge plug can be prevented from being dissolved accidentally, and the bridge plug can be controlled to start to be dissolved as required, so that the controllability of the dissolution of the bridge plug is improved, the whole bridge plug can be dissolved, and the influence on subsequent oil and gas exploitation is avoided or reduced.

Inventors

  • ZHANG WEN
  • GONG NANA
  • NIU PENGWEI
  • ZHANG HONGZHONG
  • SU MINWEN
  • FEI JIEGAO
  • DENG XIAOQIANG
  • LIAO ZUOJIE
  • MA XINDONG
  • GAO YU

Assignees

  • 中国石油天然气集团有限公司
  • 中国石油集团川庆钻探工程有限公司

Dates

Publication Date
20260508
Application Date
20241106

Claims (17)

  1. 1. An orientation controllable full-dissolution bridge plug, comprising a central tube (2), a seat seal assembly sealingly engaged to the outer peripheral surface of the central tube (2), a sealing rod (5) sealingly engaged to the inner peripheral surface of the central tube (2), the seat seal assembly comprising a packing (12), slips (10) and a push sleeve (9) located at the upper part of the central tube (2), the central tube (2) and the seat seal assembly being made of a soluble material, wherein the central tube (2) is provided with a dissolution-resistant layer only in other outer surface areas than the inner peripheral surface engaged with the sealing rod (5), the slips (10) and the push sleeve (9) are provided with a dissolution-resistant layer only in other outer surface areas than the inner peripheral surface engaged with the central tube (2), the sealing rod (5) being capable of disengaging from the central tube (2) when subjected to a predetermined pressure at its upper end surface, to allow the central tube (2), the seat seal assembly to be dissolved from inside to outside orientation.
  2. 2. The directionally controllable, fully soluble bridge plug according to claim 1, further comprising a release rod (1) partially inserted into the upper end of the center tube (2), the release rod (1) and the center tube (2) being connected by a first shear pin (3).
  3. 3. The directional controllable total solution bridge plug according to claim 2, characterized in that a pressure transmission channel (19) extending from the outer peripheral surface of the portion of the release rod (1) located outside the center tube (2) to the lower end surface is provided in the release rod (1).
  4. 4. The directional controllable full-soluble bridge plug according to claim 1, wherein a first sealing ring (4) is arranged on the upper periphery of the sealing rod (5), a second sealing ring (15) is arranged on the lower periphery of the sealing rod (5), an annular concave portion (24) between the first sealing ring (4) and the second sealing ring (15) is arranged on the periphery of the sealing rod (5), and an inner flow passage (23) which is communicated with the annular concave portion (24) and the upper side space of the sealing rod (5) is arranged inside the sealing rod (5).
  5. 5. The directional controlled total solution bridge plug according to claim 4, characterized in that the upper end face of the sealing rod (5) is provided with a blind hole communicating with the internal flow channel (23), in which blind hole a sealing grease (17) and a slidable balance plug (7) sealing the outlet of the blind hole are provided.
  6. 6. The directional controlled total solution bridge plug according to claim 1, characterized in that a third shear pin (8) is arranged between the push sleeve (9) and the central tube (2).
  7. 7. The directional controllable full-soluble bridge plug according to claim 1, wherein a support seat (13) is provided at the lower end of the center tube (2), an upper portion of the support seat (13) is joined to an outer peripheral surface of the lower end of the center tube (2), a lower end of the sealing rod (5) is joined to an inner peripheral surface of the lower portion of the support seat (13), a second shear pin (16) is provided between the sealing rod (5) and the support seat (13), and the support seat (13) is provided with a dissolution blocking layer only in other outer surface areas than the inner peripheral surfaces joined to the center tube (2) and the sealing rod (5).
  8. 8. The directionally controllable, fully soluble bridge plug of claim 7, wherein the seat assembly includes two of the slips (10) at axial ends of the packing element (12).
  9. 9. The directionally controllable, fully soluble bridge plug of claim 8, wherein the seat seal assembly further comprises a cone (11) between the slips (10) and the barrel (12), the cone (11) having a tapered portion (20) partially inserted into the slips (10), the cone (11) being provided with a dissolution barrier only in other outer surface areas than the inner circumferential surface engaged with the base pipe (2).
  10. 10. The directional controlled total solution bridge plug according to claim 9, characterized in that the cone (11) has an umbrella-shaped portion (21) connected to the conical portion (20), the umbrella-shaped portion (21) forming a conical space accommodating the insertion of the portion of the cartridge (12).
  11. 11. The directional controllable fully soluble bridge plug according to claim 10, wherein the umbrella shaped portion (21) is provided with a plurality of circumferentially spaced slits to divide the umbrella shaped portion (21) into a plurality of umbrella petals which are capable of bending and deforming outwardly.
  12. 12. The directional controlled total solution bridge plug according to claim 11, characterized in that an annular groove (22) is provided on the outer circumference of the cone (11) between the conical portion (20) and the umbrella portion (21) to allow each of the umbrella petals to bend outwards along the annular groove (22).
  13. 13. The directional controlled total solution bridge plug according to claim 9, characterized in that a fourth shear pin (18) is arranged between the cone (11) and the central tube (2).
  14. 14. The directional controlled total solution bridge plug according to claim 1, wherein the packing element (12) is made of soluble rubber.
  15. 15. The directional controlled total solution bridge plug according to claim 1, characterized in that the central tube (2) and the other parts of the seat assembly than the packing element (12) are made of magnesium-aluminium alloy, the dissolution-resistant layer comprising a ceramic film and an organic coating made by micro-arc oxidation.
  16. 16. The directionally controllable, fully soluble bridge plug of claim 15, wherein the organic coating is a polytetrafluoroethylene coating.
  17. 17. A method of using a directionally controllable, fully soluble bridge plug according to any one of claims 1 to 16, comprising: drilling down, and setting the bridge plug into an oil-gas well; The seat seal is arranged in the sleeve through the seat seal component; Pumping on, and pumping preset pressure to enable the sealing rod (5) to be separated from the central pipe (2); And dissolving the central tube (2) from inside to outside, dissolving the seat sealing assembly from inside to outside, and gradually dissolving the bridge plug completely.

Description

Directional controllable full-soluble bridge plug and application method thereof Technical Field The disclosure relates to the technical field of oil and gas well tools, in particular to a directional controllable full-soluble bridge plug and a use method of the directional controllable full-soluble bridge plug. Background At present, in order to quickly lower into a production string after the fracturing construction of an oil and gas well is completed, a well-known mode is to drill down through a pressure operation device or to lower down a speed string through a continuous oil pipe. Because the operation period of the under-pressure drilling mode is long, the cost is high, limited under-pressure operation equipment resources on the market also lead to large operation gaps of the production string, and the utilization of the under-pressure equipment to be matched with the production string often causes other high-risk wells and other stops, so that the production progress of liquid discharge production is influenced, and the efficient development of oil and gas resources is restricted. In order to improve the drilling efficiency, control the operation cost and ensure the production and production effect, the method aims at the situation that the high pressure in the underground is blocked by the open temporary blocking bridge plug of the pump after the fracturing of the directional oil-gas well with low shaft pressure is completed, the well head normal pressure is pressed into the production pipe column, and then the well completion production is put into operation, and the speed and the efficiency are improved. The existing pump open temporary blocking bridge plug does not have the performance of self complete dissolution and elimination, thus being easy to cause the blocking and production stopping of a shaft in the subsequent drainage production and the difficulty of subsequent well repair operation is increased. The temporary plugging bridge plug made of the soluble material is limited by the performance of the soluble material, the bearing capacity is limited, the dissolution controllability of parts is poor, the problems of large interference caused by different working condition factors and influence on construction safety exist, and particularly, the state of a tool after a shaft is plugged is uncontrollable and unreliable, and the well control risk exists for well head safety and normal pressure drilling. Disclosure of Invention One technical problem to be solved by the present disclosure is that dissolution after plugging a wellbore by a bridge plug is inconvenient to control. To solve the above-mentioned technical problem, an embodiment of the present disclosure provides an orientation-controllable and fully-soluble bridge plug, which includes a central tube, a seat seal assembly sealingly engaged to an outer peripheral surface of the central tube, and a seal rod sealingly engaged to an inner peripheral surface of the central tube, the seat seal assembly including a packing element, a slip, and a push sleeve located at an upper portion of the central tube, the central tube and the seat seal assembly being made of a soluble material, wherein the central tube is provided with a dissolution-resistant layer only in other outer peripheral areas than the inner peripheral surface engaged with the seal rod, the slip and the push sleeve are provided with a dissolution-resistant layer only in other outer peripheral areas than the inner peripheral surface engaged with the central tube, and the seal rod is capable of being disengaged from the central tube when an upper end surface thereof is subjected to a predetermined pressure, so as to allow the central tube and the seat seal assembly to be dissolved from inside to outside orientation. In some embodiments, a release rod is also included that is partially inserted into the upper end of the base pipe, the release rod and the base pipe being connected by a first shear pin. In some embodiments, the release rod is provided therein with a pressure transmission channel extending from an outer peripheral surface of a portion of the release rod located outside the center tube to a lower end surface. In some embodiments, a first sealing ring is arranged on the upper periphery of the sealing rod, a second sealing ring is arranged on the lower periphery of the sealing rod, an annular concave part positioned between the first sealing ring and the second sealing ring is arranged on the periphery of the sealing rod, and an inner runner which is communicated with the annular concave part and the upper side space of the sealing rod is arranged inside the sealing rod. In some embodiments, the upper end surface of the sealing rod is provided with a blind hole in communication with the internal flow passage, in which a sealing grease and a slidable balance plug sealing the outlet of the blind hole are provided. In some embodiments, a third shear pin is disposed between the