Annular balance pressure guide type protective continuous thin interlayer fracturing tubular column
Through the design of the continuous thin partition fracturing pipe column of annular balancing pressure-guided type, the combination of balanced packer and K344 packer is used to solve the problem of poor fracturing effect in old wells and realize thin partitioning The effective protection of the layer ensures the improvement of the fracturing effect and the oil production capacity of the oil layer.
Patent Information
- Application Number
- CN202421064545.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-16
- Publication Date
- 2025-01-14
- Estimated Expiration
- 2034-05-16
AI Technical Summary
The prior art is difficult to effectively perform thin interlayer equilibrium flow restriction fracturing in old wells, especially the exploitation of medium and low permeability oil layers and inclusion continuous thin partitions in thick oil layers, and cannot effectively release oil production capacity.
The continuous thin partition fracturing pipe column is adopted by an annular balancing pressure guide type protection. Through the combination of K344 packer, balanced packer and sandblaster, the balanced packer is used to seal the thin partition at the thin partition, and high-pressure liquid passes through The liquid conduction channel enters the balance layer, protecting the thin partition from high pressure breakdown and ensuring the fracturing effect.
It realizes effective protection of thin partitions during fracturing, avoids pressure rupture of oil layer, and ensures the fracturing transformation effect. It is especially suitable for the protection of multiple thin partitions, enhancing the oil production capacity of the oil layer.
Smart Images
Figure CN222350695U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of oilfield oil-increasing and injection-increasing transformation, in particular to an annular space balance pressure-conducting type protection continuous thin-layer fracturing pipe column. Background Art
[0002] At present, it is impossible to perform thin interlayer balanced flow limiting fracturing for old wells that have been perforated with high density by conventional methods. Usually, conventional staged fracturing technology is generally used for such wells. During fracturing construction, only the main oil layer with higher permeability can be fractured among the several target layers in the fixture, and other thin and poor layers with higher breaking pressure cannot be effectively fractured. Especially in the middle and late stages of oil field development, the medium and low permeability oil layers in the thick oil layers are also in urgent need of releasing their oil production capacity. However, there is no effective exploitation process for the situation where the thick oil layers are interspersed with continuous thin interlayers. In order to realize the fixed-point fracturing of the low aquifer depth inside the thin and poor layers and the high aquifer under conventional perforation conditions, as well as the exploitation of small layer reserves in the thick oil layers mixed with continuous thin interlayers, it is urgent to study the fracturing process technology that can protect the thin interlayer multiple times. Summary of the invention
[0003] In order to overcome the deficiency that thin and poor layers cannot be effectively fractured during existing fracturing construction, the utility model provides an annular balanced pressure-conducting protection continuous thin-layer fracturing string. The annular balanced pressure-conducting protection continuous thin-layer fracturing string can protect the thin layer from high-pressure breakdown during the implementation of the fracturing process, avoid the formation of oil layer pressure channeling, and ensure the fracturing transformation effect.
[0004] The technical solution of the utility model is: an annular balanced pressure-conducting protection continuous thin barrier fracturing string, including an oil pipe, a plurality of K344 packers, a balanced packer and a sandblaster are connected to the oil pipe, the position of the K344 packer on the string corresponds to the barrier in the formation, the sandblaster corresponds to the target oil layer, and the balanced packer corresponds to the thin barrier;
[0005] The balanced packer includes a center tube, a rubber tube is provided on the outside of the center tube, an upper rubber tube seat and a lower rubber tube seat are respectively provided at the upper and lower ends of the rubber tube, an upper liquid hole is opened on the side wall of the upper rubber tube seat, and a lower liquid hole is opened on the side wall of the lower rubber tube seat. An axial liquid guide channel is provided on the side wall of the center tube, and the upper and lower ends of the liquid guide channel are respectively connected to the upper liquid hole and the lower liquid hole.
[0006] Furthermore, an axial groove is opened on the outer surface of the side wall of the central tube, and a liquid guide plate is fixed between the two side walls of the groove. A liquid guide channel is formed between the liquid guide plate and the inner wall of the groove, and the upper end of the liquid guide plate is located at the lower edge of the upper liquid hole, and the lower end of the liquid guide plate is located at the upper edge of the lower liquid hole.
[0007] Furthermore, the upper end of the central tube is connected to the upper joint, and an anti-rotation pin is provided between the central tube and the upper joint.
[0008] Furthermore, the lower end of the center tube is connected to the lower joint, an anti-slip ring is provided between the center tube and the lower joint, the upper end of the anti-slip ring is connected to the center tube by a thread, and the lower end is connected to a mortise and tenon fixing ring by a mortise and tenon fixing ring, a protruding prism is provided on the outer surface of the mortise and tenon fixing ring, and the prism is located in the anti-rotation groove of the inner wall of the lower joint.
[0009] Furthermore, the thin barrier is a barrier having a thickness of less than 0.8 meters.
[0010] Furthermore, the oil pipe is connected to the third K344 packer, the sleeve sandblaster, the second K344 packer, the sleeve-free sandblaster, the balanced packer, and the first K344 packer in sequence from top to bottom, wherein the first K344 packer is located at the lower end of the tubing, the balanced packer corresponds to the thin barrier layer, the second K344 packer and the third K344 packer are the first barrier layer and the second barrier layer respectively, the sleeve-free sandblaster and the sleeve sandblaster correspond to the first target oil layer and the second target oil layer respectively.
[0011] Furthermore, the oil pipe is connected to the second K344 packer, the second sleeve sandblaster, the second balanced packer, the first sleeve sandblaster, the first balanced packer, the sleeveless sandblaster, and the first K344 packer in sequence from top to bottom, wherein the first K344 packer is located at the lower end of the tubing string, the first balanced packer corresponds to the first thin barrier layer, the second balanced packer corresponds to the second thin barrier layer, the sleeveless sandblaster and the two sleeve sandblasters correspond to different target oil layers, respectively.
[0012] The utility model has the following beneficial effects: due to the adoption of the above scheme, the balanced packer and the K344 packer produce a sealing effect, and the opening of the sand outlet of each sandblaster is controlled by throwing a ball and hitting a sleeve, so as to realize the pressure setting of multiple layers. In particular, the balanced packer should be set at the depth where the thin interlayer is located. When the target layer is fractured by injecting fluid into the oil pipe, the fracturing fluid enters the oil casing annulus from the sand outlet of the sandblaster and enters the target layer. At the same time, the high-pressure liquid in the annulus also follows the liquid guide channel of the balanced sandblaster, crosses the rubber cylinder of the sealing, and enters the balanced layer, so that the pressure in the balanced layer rises, thereby protecting the thin interlayer from being damaged by unilateral high pressure. Similarly, if there are continuous thin interlayers that need to be protected by balanced pressure, multiple balanced packers can be used when assembling the pipe string, so that the balanced packers are set at the depth where multiple thin interlayers are located. In this way, by throwing a ball and hitting a sleeve, when each target layer is fractured, balanced pressure can enter the balanced layer, thereby protecting multiple thin interlayers, avoiding the formation of oil layer pressure channeling, and ensuring the fracturing transformation effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a schematic diagram of a pipe column protecting a thin barrier layer for a pipe column of the utility model;
[0014] Figure 2This is a schematic diagram of a pipe column protecting multiple thin layers in the utility model;
[0015] Figure 3 is a structural schematic diagram of a balanced packer;
[0016] Figure 4 is along Figure 3 Sectional view of AA.
[0017] In the figure, 1-upper joint, 2-pressure cap, 3-anti-rotation pin, 4-center tube, 5-upper rubber tube seat, 6-rubber tube, 7-liquid guide plate, 8-lower rubber tube seat, 9-anti-slip retaining ring, 10-lower joint, 11-tenon groove fixing ring, 12-upper liquid hole, 13-liquid guide channel, 14-lower liquid hole, 101-oil pipe, 102-casing, 103-1-first K344 packer, 103-2-second K344 packer, 104-balance packer, 104-1-first balance Balance packer, 104-2-second balance packer, 105-sleeveless sandblaster, 106-sleeve sandblaster, 106-1-first sleeve sandblaster, 106-2-second sleeve sandblaster, 107-interlayer, 107-1-first interlayer, 107-2-second interlayer, 108-1-first target oil layer, 108-2-second target oil layer, 109-thin interlayer, 109-1-first thin interlayer, 109-2-second thin interlayer, 110-balanced oil layer. DETAILED DESCRIPTION
[0018] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments, and the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0019] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by "up", "down", "left", "right", "inside", "outside", "top" and "bottom" are all based on the directions or positional relationships shown in the accompanying drawings. The purpose is only to facilitate the description of the present invention and simplify the description. It does not indicate or imply that the referred parts must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.
[0020] Depend on Figures 1 to 4As shown, an annular balanced pressure-conducting protection continuous thin-layer fracturing string includes an oil pipe 101, to which are connected a plurality of K344 packers, balanced packers and sandblasters. The position of the K344 packer on the string corresponds to the barrier in the formation, the sandblaster corresponds to the target oil layer, and the balanced packer corresponds to the thin barrier, wherein the thin barrier is a barrier with a thickness of less than 0.8 meters.
[0021] The balanced packer comprises an upper joint 1, the lower end of which is internally threadedly connected to a center pipe 4, a pressure cap 2 is provided on the upper part of the center pipe 4, the pressure cap 2 is threadedly connected to the inside of the upper joint 1, and an anti-rotation pin 3 is provided between the center pipe 4 and the upper joint 1. The lower end of the upper joint 1 is externally connected to an upper rubber tube seat 5, a rubber tube 6 is provided on the outside of the center pipe 4, the rubber tube 6 is arranged below the upper rubber tube seat 5, and a lower rubber tube seat 8 is provided at the lower part of the rubber tube 6, the lower part of the lower rubber tube seat 8 is connected to a lower joint 10, and the lower joint 10 is internally threadedly connected to the center pipe 4. A plurality of upper fluid holes 12 are provided on the side wall of the upper rubber tube seat 5, and a plurality of lower fluid holes 14 are provided on the side wall of the lower rubber tube seat 8, and the upper and lower fluid holes are respectively located on the upper and lower sides of the rubber tube 6. The side wall of the central tube 4 is provided with a plurality of axial liquid guiding channels 13, which are located opposite to the upper and lower liquid holes, and the upper and lower ends of the liquid guiding channels 13 are respectively connected to the upper liquid hole 12 and the lower liquid hole 14, so that the upper and lower sides of the rubber cylinder 6 are connected.
[0022] The liquid guiding channel 13 can be formed by the following structure: an axial groove is opened on the outer surface of the side wall of the central tube 4, and the groove corresponds to the upper and lower liquid holes. A liquid guiding plate 7 is fixed between the two side walls of the groove close to the outer wall of the central tube. There is a gap between the liquid guiding plate 7 and the bottom of the groove, and this gap forms the liquid guiding channel 13. The upper end of the liquid guiding plate 7 is located at the lower edge of the upper liquid hole 12, and the lower end of the liquid guiding plate 7 is located at the upper edge of the lower liquid hole 14, so that the liquid guiding channel 13 connects the upper and lower liquid holes.
[0023] The lower end of the center tube 4 is connected to the lower joint 10, and an anti-slip ring 9 is provided between the center tube 4 and the lower joint 10. The upper end of the anti-slip ring 9 is connected to the center tube 4 by threads, and the lower end is connected to a mortise and tenon fixing ring 11 by a mortise and tenon. The outer surface of the mortise and tenon fixing ring 11 is provided with a protruding prism, and the prism is located in the anti-rotation groove of the inner wall of the lower joint 10. This structure can limit the rotation of the center tube 4, thereby preventing undercutting.
[0024] The following is an introduction to the fracturing string based on the number and location of thin interlayers. Figure 1, protecting a thin barrier, there is a thin barrier 109 between the oil layers below the first target oil layer 108-1, and the oil layer below can be regarded as the balance oil layer 110. Above the target oil layer 108 are the first barrier 107-1, the second target oil layer 108-2, and the second barrier 107-2. At this time, when designing the string, the balance packer must be designed to the depth of the thin barrier 109, and the remaining K344 packers are designed at the depth of other barriers. That is, the oil pipe 101 is connected in sequence to the third K344 packer 103-3, the sleeve sandblaster 106, the second K344 packer 103-2, the sleeve-free sandblaster 105, the balanced packer 104, and the first K344 packer 103-1, wherein the third K344 packer 103-3 corresponds to the second barrier layer 107-2, the sleeve sandblaster 106 corresponds to the second target oil layer 108-2, the second K344 packer 103-2 corresponds to the first barrier layer 107-1, the sleeve-free sandblaster 105 corresponds to the first target oil layer 108-1, the balanced packer 104 corresponds to the thin barrier layer 109, and the first K344 packer 103-1 is located at the lower end of the balanced oil layer 110.
[0025] During operation, high-pressure liquid is injected into the pipe column. The sand outlet of the sleeve sandblaster 106 is blocked by the sleeve and liquid cannot be discharged. There is no sleeve in the sleeveless sandblaster 105. The high-pressure liquid passes through the oil casing annulus and the perforations of the casing from the sand outlet of the sleeveless sandblaster 105 to enter the target oil layer for fracturing and press open the cracks. At the same time, the high-pressure liquid also passes through the annular liquid guide channel 13 of the balanced packer 105, enters the oil casing annulus of the balanced oil layer, and enters the balanced oil layer through the perforations of the casing. In this way, a balanced pressure is established in the upper and lower oil layers of the thin barrier 109, thereby protecting the thin barrier 109 from high-pressure breakdown during the implementation of the fracturing process, and avoiding the formation of oil layer pressure channeling to affect the fracturing transformation effect.
[0026] like Figure 2 , protecting multiple continuous thin barriers, taking the protection of two continuous thin barriers by three layers of pressure as an example, the first target oil layer 108-1, the second target oil layer 108-2, and the third target oil layer 108-3 of the fracturing target oil layer are continuous oil layers, and there are two thin barriers in between, namely the first thin barrier 109-1 and the second thin barrier 109-2. When designing the fracturing string, the first balanced packer 104-1 and the second balanced packer 104-2 must be designed at the depth of the first thin barrier 109-1 and the second thin barrier 109-2 respectively, the first K344 packer 103-1 is designed at the lower end of the string, and the second K344 packer 103-2 is designed at the barrier 107.
[0027] During operation, high-pressure liquid is injected into the pipe column. The sand outlets of the first sleeve sandblaster 106-1 and the second sleeve sandblaster 106-2 are blocked by the sleeve and cannot discharge liquid. There is no sleeve in the sleeveless sandblaster 105. The high-pressure liquid passes through the oil casing annulus and the perforations of the casing from the sand outlet of the sleeveless sandblaster 105 to enter the first target oil layer 108-1 for fracturing and open the cracks. At the same time, the high-pressure liquid also passes through the annular liquid guide channel 13 of the first balanced packer 104-1, enters the oil casing annulus of the second target oil layer 108-2, and enters the second target oil layer 108-2 through the perforations of the casing. In this way, a balanced pressure is established in the upper and lower oil layers of the first thin barrier 109-1. When the first layer is fracturing, the ball is thrown to knock out the sliding sleeve in the second sliding sleeve sandblaster 106-2. At this time, the sand outlet of the second sliding sleeve sandblaster 106-2 is exposed. Without the sliding sleeve sandblaster 105, the second sliding sleeve sandblaster 106-2 cannot discharge liquid. Similarly, when the high-pressure liquid enters the second target oil layer 108-2, it also passes through the annular liquid guide channel 13 of the second balanced packer 104-2, enters the oil casing annulus of the first target oil layer 108-1 and the third target oil layer 108-3, and enters the first target oil layer 108-1 and the third target oil layer 108-3 through the perforation of the casing. The second target oil layer 108-2 is fracturing, and the first thin barrier layer 109-1 and the second thin barrier layer 109-2 above and below are both subjected to balanced pressure, avoiding the formation of oil layer pressure channeling, and ensuring the fracturing transformation effect.
[0028] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.
Claims
1. An annular balance pressure-conducting protection continuous thin-layer fracturing string, comprising an oil pipe (101), characterized in that: The oil pipe (101) is connected to a plurality of K344 packers, balanced packers and sandblasters, wherein the position of the K344 packers on the pipe string corresponds to the interlayer in the formation, the sandblasters correspond to the target oil layer, and the balanced packers correspond to the thin interlayer; The balanced packer comprises a central tube (4), a rubber tube (6) is arranged outside the central tube (4), an upper rubber tube seat (5) and a lower rubber tube seat (8) are arranged at the upper and lower ends of the rubber tube (6), an upper fluid hole (12) is opened on the side wall of the upper rubber tube seat (5), and a lower fluid hole (14) is opened on the side wall of the lower rubber tube seat (8), an axial fluid guide channel (13) is arranged on the side wall of the central tube (4), and the upper and lower ends of the fluid guide channel (13) are respectively connected to the upper fluid hole (12) and the lower fluid hole (14).
2. The annular balance pressure-conducting protection continuous thin-layer fracturing string according to claim 1 is characterized by: An axial groove is formed on the outer surface of the side wall of the central tube (4), a liquid guide plate (7) is fixed between the two side walls of the groove, a liquid guide channel (13) is formed between the liquid guide plate (7) and the inner wall of the groove, and the upper end of the liquid guide plate (7) is located at the lower edge of the upper liquid hole (12), and the lower end of the liquid guide plate (7) is located at the upper edge of the lower liquid hole (14).
3. The annular balance pressure-conducting protection continuous thin-layer fracturing string according to claim 2 is characterized by: The upper end of the central tube (4) is connected to the upper joint (1), and an anti-rotation pin (3) is provided between the central tube (4) and the upper joint (1).
4. The annular balance pressure-conducting protection continuous thin-layer fracturing string according to claim 3 is characterized by: The lower end of the center tube (4) is connected to the lower joint (10), an anti-slip retaining ring (9) is provided between the center tube (4) and the lower joint (10), the upper end of the anti-slip retaining ring (9) is connected to the center tube (4) by means of a thread, and the lower end is connected to a tenon-groove fixing ring (11) by means of a tenon-groove, the outer surface of the tenon-groove fixing ring (11) is provided with a protruding prism, and the prism is located in an anti-rotation groove on the inner wall of the lower joint (10).
5. The annular balance pressure-conducting protection continuous thin-layer fracturing string according to claim 4 is characterized by: The thin interlayer is an interlayer with a thickness less than 0.8 meters.
6. The annular balance pressure-conducting protection continuous thin-layer fracturing string according to claim 1 is characterized by: The oil pipe (101) is connected to the third K344 packer (103-3), the sleeve sandblaster (106), the second K344 packer (103-2), the sleeve-free sandblaster (105), the balanced packer (104), and the first K344 packer (103-1) in sequence from top to bottom, wherein the first K344 packer (103-1) is located at the lower end of the pipe string, the balanced packer (104) corresponds to the thin barrier layer (109), the second K344 packer (103-2) and the third K344 packer (103-3) are respectively the first barrier layer (107-1) and the second barrier layer (107-2), and the sleeve-free sandblaster (105) and the sleeve sandblaster (106) correspond respectively to the first target oil layer (108-1) and the second target oil layer (108-2).
7. The annular balance pressure-conducting protection continuous thin-layer fracturing string according to claim 1 is characterized by: The oil pipe (101) is connected to the second K344 packer (103-2), the second sleeve sandblaster (106-2), the second balanced packer (104-2), the first sleeve sandblaster (106-1), the first balanced packer (104-1), the non-sleeve sandblaster (105), and the first K344 packer (103-1) in sequence from top to bottom, wherein the first K344 packer (103-1) is located at the lower end of the pipe string, the first balanced packer (104-1) corresponds to the first thin barrier layer (109-1), the second balanced packer (104-2) corresponds to the second thin barrier layer (109-2), and the non-sleeve sandblaster (105) and the two sleeve sandblasters correspond to different target oil layers, respectively.