Unidirectional sealing soluble bridge plug

Abstract

A one-way sealing soluble bridge plug relates to the technical field of oil field downhole tools, the lower part of a central pipe is in threaded connection with a guide shoe, the central pipe is sequentially sleeved with a positioning sleeve, a rubber sleeve, a cone and a slip from top to bottom, the outer circle of the slip is provided with axial cracking grooves, the cracking grooves are circumferentially and uniformly arranged, the cone is connected with the slip through a conical ring surface, and the slip is connected with the rubber sleeve. The positioning sleeve is connected with the central tube through a shear pin A. The cone is connected with the central tube through a shear pin B. The fracturing device has the advantages that after fracturing is finished, the upper portion of the fracturing ball is decompressed, flowback liquid at the bottom of a well flows upwards, the sliding sleeve moves upwards under the action of the compression spring to expose the overflowing hole, the flowback liquid flows to the ratchet position between the positioning sleeve and the center pipe from the overflowing hole, the positioning sleeve and the rubber sleeve are unsealed, and the fracturing device is used for fracturing. Flow-back liquid at the bottom of the well can flow upwards from the two sides outside the center pipe, the problem that flowing dead angles exist at the position of a rubber sleeve of an existing bridge plug is solved, the flow-back liquid flows upwards from the interior of the center pipe at the same time, and therefore the dissolving speed of the bridge plug is increased.

Description

TECHNICAL FIELD

[0001] The utility model relates to oilfield downhole tool technology field especially relates to one -way sealed soluble bridge plug. BACKGROUND

[0002] The announcement number CN 222478698 U discloses a one -way sealed soluble bridge plug, the one -way sealed soluble bridge plug is set up guide flow groove on the inner wall of the center tube and / or the center hole of the guide shoe, thereby when the fracturing ball card groove guide shoe's center hole or the center tube, the backflow liquid can bypass the fracturing ball from the guide flow groove, guarantee the flow of backflow liquid is smooth, guarantee the dissolving speed of one -way sealed soluble bridge plug.

[0003] However, the technology has the following defects: after fracturing, the soluble rubber cylinder has not been unsealed under the action of the lock ring, the backflow liquid flowing from the bottom cannot flow from the outside of the center, that is, there is a liquid flow dead angle at the soluble rubber cylinder part of the bridge plug, which reduces the dissolving time of the bridge plug. UTILITY MODEL CONTENT

[0004] In order to solve the problem of reducing the dissolving speed of the bridge plug at present, the utility model provides a one -way sealed soluble bridge plug.

[0005] The utility model provides a technical scheme: a one -way sealed soluble bridge plug, including center tube, be equipped with the shear pin of the hand of center tube, the lower part of center tube is connected with the guide shoe, and the center tube is successively sleeved with the positioning sleeve, rubber cylinder, vertebral body and slip from top to bottom, the outer circle of slip is opened with the axial cracking groove, and the cracking groove is uniformly arranged in circumference, and the vertebral body and slip are connected through the conical ring surface, the positioning sleeve is connected with the center tube through the shear pin A, the vertebral body is connected with the center tube through the shear pin B, the upper part of center tube hole is processed with the step hole, the slide sleeve is installed in the step hole of center tube, the upper part of slide sleeve is equipped with the ball seat hole, and the ball seat hole is sealedly connected with the fracturing ball, and the compression spring is equipped between the lower part of slide sleeve and the step ring surface of step hole, the overflow hole is opened in the slide sleeve part of center tube, and the sealing ring is arranged in the overflow hole both sides of center tube.

[0006] The overflow hole is opened outwardly upward in the pipe wall of the center tube.

[0007] The outer end port of the overflow hole corresponds to the positioning sleeve after the rubber cylinder is set.

[0008] The positioning sleeve and the center tube are equipped with the interlocking ratchet.

[0009] The guide shoe extends a section of the extension section downward, the extension section has the coaxial center hole with the center tube and communicates, and the lower transverse notch is opened around the extension section.

[0010] The central tube, positioning sleeve, cone, slip, sliding sleeve, and fracturing ball are all made of soluble metal, while the rubber sleeve is made of soluble rubber.

[0011] The beneficial effects of this utility model are as follows: After fracturing, the upper part of the fracturing ball is depressurized, and the flowback fluid at the bottom of the well flows upward. Under the action of the compression spring, the sliding sleeve moves upward to expose the flow hole. The flowback fluid flows from the flow hole to the ratchet position between the positioning sleeve and the central tube. Since the ratchet is very small, it can dissolve quickly. Thus, the axial limit of the positioning sleeve is first unsealed. The rubber sleeve retracts under its own elasticity. After the rubber sleeve is unsealed, the flowback fluid at the bottom of the well can flow upward from both sides of the central tube, which solves the problem of dead flow in the rubber sleeve part of the previous bridge plug. At the same time, the flowback fluid flows upward from inside the central tube, thereby accelerating the dissolution rate of the bridge plug. Attached Figure Description

[0012] Appendix Fig. 1 This is a schematic diagram of the structure of this utility model;

[0013] Appendix Fig. 2 This is a schematic diagram of the structure of this utility model after it has been sealed.

[0014] In the diagram, 1-Central tube, 2-Positioning sleeve, 3-Rubber tube, 4-Pelvis, 5-Clip, 6-Guide shoe, 61-Extended section, 62-Transverse notch, 7-Fracturing ball, 8-Sliding sleeve, 9-Flow hole, 10-Release shear screw hole, 11-Setting pin A, 12-Setting pin B, 13-Step hole, 14-Ball seat hole, 15-Crack groove. Detailed Implementation

[0015] like Figs. 1-2 As shown, a unidirectional sealing soluble bridge plug includes a central tube 1 with a release shear pin 10 for connecting a setting tool. A guide shoe 6 is threaded to the lower part of the central tube 1. From top to bottom, the central tube 1 is fitted with a positioning sleeve 2, a rubber sleeve 3, a cone 4, and a slip 5. The slip 5 has axially oriented cracking grooves 15 evenly distributed around its circumference. When the cone 4 descends, the cracking grooves 15 break, and the slip 5 disassembles into an outwardly expandable split structure. The cone 4 and the slip 5 are connected by a conical annular surface. The positioning sleeve 2 is connected to the central tube 1 via shear pin A11, and the cone 4 is connected to the central tube 1 via shear pin B12 to prevent premature sealing. The upper part of the inner hole of the central tube 1 is machined with a stepped hole 13, and a sliding sleeve 8 is installed in the stepped hole 13 of the central tube 1. The upper part of the sliding sleeve 8 is provided with a ball seat hole 14, which is sealed to the fracturing ball 7. A compression spring is provided between the lower part of the sliding sleeve 8 and the stepped annular surface of the stepped hole 13. The central tube 1 has an overflow hole 9 at the sliding sleeve 8, and the central tube 1 has sealing rings on both sides of the overflow hole 9.

[0016] The flow passage 9 is opened upward and outward on the pipe wall of the central pipe 1 to serve as a flow guide.

[0017] After the rubber sleeve 3 is set, the outer port of the flow hole 9 corresponds to the positioning sleeve 2.

[0018] The positioning sleeve 2 and the central tube 1 are provided with interlocking ratchet teeth to prevent the positioning sleeve 2 from moving upward after setting.

[0019] The guide shoe 6 extends downward to a protruding section 61. The protruding section 61 has a central hole that is coaxial with and connected to the central tube 1. The protruding section 61 has a lower transverse notch 62 around its perimeter. Even if the lower fracturing ball 7 is stuck at the lower opening of the guide shoe 6, the backflow liquid can flow from the notch 62 into the interior of the central tube 1.

[0020] The central tube 1, positioning sleeve 2, cone 4, slip 5, sliding sleeve 8 and fracturing ball 7 are all made of soluble metal, and the rubber sleeve 3 is made of soluble rubber.

[0021] After fracturing, the upper part of the fracturing ball 7 is depressurized, and the flowback fluid at the bottom of the well flows upward. The sliding sleeve 8 moves upward under the action of the compression spring to expose the flow hole 9. The flowback fluid flows from the flow hole 9 to the ratchet position between the positioning sleeve 2 and the central tube 1. Since the ratchet is very small, it dissolves quickly. Thus, the axial limit of the positioning sleeve 2 is first unsealed. The rubber sleeve 3 retracts under its own elasticity. After the rubber sleeve 3 is unsealed, the flowback fluid at the bottom of the well can flow upward from both sides of the central tube 1, which solves the problem of the dead flow angle in the rubber sleeve 3 part of the bridge plug in the past. At the same time, the flowback fluid flows upward from inside the central tube 1, thereby accelerating the dissolution rate of the bridge plug.

Claims

1. A unidirectional sealing soluble bridge plug, comprising a central tube (1), characterized in that: The central tube (1) is provided with a shear pin (10). The lower part of the central tube (1) is threaded to a guide shoe (6). The central tube (1) is fitted with a positioning sleeve (2), a rubber sleeve (3), a cone (4) and a slip (5) from top to bottom. The outer circle of the slip (5) has an axial cracking groove (15). The cracking groove (15) is evenly arranged around the circumference. The cone (4) and the slip (5) are connected by a conical annular surface. The positioning sleeve (2) is connected to the central tube (1) by a shear pin A (11). The cone (4) is connected by a shear pin. Nail B (12) connects to the central tube (1). The upper part of the inner hole of the central tube (1) is machined with a stepped hole (13). A sliding sleeve (8) is installed in the stepped hole (13) of the central tube (1). A ball seat hole (14) is provided on the upper part of the sliding sleeve (8). The ball seat hole (14) is sealed to the fracturing ball (7). A compression spring is provided between the lower part of the sliding sleeve (8) and the stepped annular surface of the stepped hole (13). The central tube (1) has an overflow hole (9) at the sliding sleeve (8). The central tube (1) has sealing rings on both sides of the overflow hole (9).

2. The unidirectional sealing soluble bridge plug according to claim 1, characterized in that: The flow hole (9) is opened upward and outward on the pipe wall of the central tube (1).

3. The unidirectional sealing soluble bridge plug according to claim 1, characterized in that: After the rubber tube (3) is set, the outer port of the flow hole (9) corresponds to the positioning sleeve (2).

4. The unidirectional sealing soluble bridge plug according to claim 1, characterized in that: The positioning sleeve (2) and the central tube (1) are provided with interlocking ratchet teeth.

5. The unidirectional sealing soluble bridge plug according to claim 1, characterized in that: The shoe (6) extends downwards to a protruding section (61), which has a central hole that is coaxial with and connected to the central tube (1). The protruding section (61) has a lower transverse notch (62) around its perimeter.

6. The unidirectional sealing soluble bridge plug according to claim 1, characterized in that: The central tube (1), positioning sleeve (2), cone (4), slip (5), sliding sleeve (8) and fracturing ball (7) are all made of soluble metal, and the rubber tube (3) is made of soluble rubber.

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