Casing pipe pressure balance sliding sleeve

Abstract

The utility model relates to the technical field of oil and gas well fracturing, and discloses a casing pressure balancing sliding sleeve which comprises a first casing, a first fracturing hole and a second fracturing hole are formed in the outer side face of the first casing, a first sliding groove is formed in the first casing, and a first sliding sleeve is installed in the first sliding groove in a sliding mode. The left end of the first casing pipe is connected with a communicating pipe, the left end of the communicating pipe is connected with a second casing pipe, a third fracturing hole is formed in the outer side face of the second casing pipe, a second sliding groove and a limiting groove are formed in the second casing pipe, and a second sliding sleeve is slidably installed in the second sliding groove; a second plugging ball is installed in the second sliding sleeve, and an elastic limiting block is installed at the right end of the second sliding sleeve. The fracturing fluid is pumped into the first casing pipe, and the fracturing fluid can be used for fracturing the stratum rock at the first fracturing hole through the first fracturing hole, so that the development efficiency of oil and gas resources can be effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of oil and gas well fracturing, in particular to a casing pressure balancing sliding sleeve. Background Art

[0002] Oil and gas well fracturing technology, also known as hydraulic fracturing, is a physical engineering technology used to increase the productivity of oil and gas wells. It uses a high-pressure pump to inject water or other liquids into the formation to create cracks in the rock so that oil and gas can be released from the formation, increasing the flow capacity of oil and gas, thereby increasing the production of oil wells. In the fracturing operation, in order to effectively transmit pressure to the formation and form cracks, it is necessary to accurately control the flow and pressure of the liquid. Therefore, a casing pressure balance sleeve is needed to achieve precise control of the flow rate, ensuring that the fracturing fluid can flow along the predetermined path and speed, thereby improving the efficiency and success rate of fracturing.

[0003] According to the search, the Chinese patent document, announcement number: CN220015127U, discloses a high-pressure sandblasting sleeve for fracturing. By dropping a plugging ball onto the ball seat, the elastic pawl moves to the inside of the second positioning groove under the action of gravity, which is the open state of the sleeve. However, in actual use, the device can only perform fracturing on one section, and cannot effectively achieve multiple fracturing on multiple sections in one pipeline; in addition, if multiple fracturing holes are set in the same sleeve, it will affect the fracturing efficiency and success rate, reducing the overall practicality of the device. Utility Model Content

[0004] 1. Technical issues to be resolved

[0005] In view of the deficiencies in the prior art, the utility model provides a casing pressure balance sliding sleeve, which has the advantages of multi-stage segmented fracturing, good fracturing effect, and improved fracturing success rate, thereby solving the above technical problems.

[0006] (II) Technical solution

[0007] To achieve the above-mentioned objectives, the utility model provides the following technical solutions: a casing pressure balancing sleeve, comprising a first casing, a first fracturing hole and a second fracturing hole are provided on the outer side surface of the first casing, a first sliding groove is provided inside the first casing, a first sliding sleeve is slidably installed inside the first sliding groove, a first blocking ball is installed inside the first sliding sleeve, a connecting pipe is fixedly connected to the left end of the connecting pipe, a second casing is fixedly connected to the left end, a third fracturing hole is provided on the outer side surface of the second casing, a second sliding groove and a limiting groove are provided inside the second casing, a second sliding sleeve is slidably installed inside the second sliding groove, a second blocking ball is installed inside the second sliding sleeve, and an elastic limiting block is fixedly installed on the right end of the second sleeve.

[0008] Preferably, the number of the first fracturing holes, the second fracturing holes and the third fracturing holes are all four.

[0009] Through the above technical scheme, by pumping fracturing fluid into the interior of the first casing and the second casing to form high pressure, the fracturing fluid can respectively pass through the first fracturing hole, the second fracturing hole and the third fracturing hole to break the formation rock and generate cracks, thereby effectively improving the development efficiency of oil and gas resources. The first fracturing hole, the second fracturing hole and the third fracturing hole at different locations can not only effectively increase the production of oil and gas wells, but also form a continuous artificial fracture network, improve fracturing efficiency and reduce costs.

[0010] Preferably, a convex limiting ring is provided inside the first sliding sleeve near the left end, the diameter of the first blocking ball is larger than the inner diameter of the convex limiting ring, and the first sliding sleeve is installed inside the first sleeve near the right end.

[0011] Through the above technical scheme, by pumping fracturing fluid into the interior of the first casing and forming high pressure, the fracturing fluid can fracture the formation rock here through the first fracturing hole; then the first sealing ball is put into the interior of the first casing and the fracturing fluid is pumped, and when the first sealing ball moves to the position of the convex limit ring, the first sleeve can be effectively sealed, and as the fracturing fluid is continuously pumped in, the pressure inside the first casing also increases accordingly, and then when the pressure reaches a certain critical value, the first sealing ball and the first sleeve can be pushed to slide inside the first slide groove, and the first sleeve can then expose the second fracturing hole and seal the first fracturing hole, and then the fracturing fluid can fracture the formation rock here through the second fracturing hole, thereby effectively improving the fracturing efficiency and success rate.

[0012] Preferably, a guide block is provided inside the second sliding sleeve near the left end.

[0013] Through the above technical solution, when the first sealing ball or the second sealing ball is dropped from the inside of the second casing, the guide block can play a good guiding role. At the same time, when the fracturing fluid is pumped in, it can also ensure that it moves along a predetermined path, ensuring a stable environment inside the pipe and maintaining pressure balance in the device.

[0014] Preferably, there are four elastic limit blocks, which are tightly connected to each other inside the second slide groove, and the inner diameter of the limit groove is slightly larger than the inner diameter of the second slide groove, and the diameter of the second blocking ball is slightly larger than the inner diameter formed by the four elastic limit blocks.

[0015] When the fracturing of the second fracturing hole is completed, the second sealing ball can be put in, and fracturing fluid can be pumped into the interior of the second casing at the same time. When the second sealing ball moves to the position of the four elastic limit blocks, the second sleeve can be effectively sealed. As the fracturing fluid is continuously pumped in, the pressure inside the second casing increases accordingly. Then, when the pressure reaches a certain critical value, the second sealing ball and the second sleeve can be pushed to slide inside the second slide groove. As the second sleeve moves, the third fracturing hole can be exposed. Then, the fracturing fluid can fracture the formation rock here through the second fracturing hole. At the same time, when the four elastic limit blocks are completely moved to the interior of the limit groove, they can move outward respectively. At this time, the second sealing ball can pass through here and continue to move to the right. Therefore, different numbers of second casings, second sleeves and other parts can be connected according to different construction lengths or depths. The second sealing ball can seal and fracture them in turn, thereby improving the overall practicality and work efficiency of the device.

[0016] Preferably, the diameter of the first blocking ball is smaller than the inner diameter formed by the four elastic limiting blocks.

[0017] Through the above technical solution, the first sealing ball can be dropped into the first sleeve through the second sleeve and the connecting pipe, so the first sealing ball can directly pass through the four elastic limit blocks and move to the inside of the first sliding sleeve, thereby improving the overall practicality of the device and ensuring the overall normal operation.

[0018] Compared with the prior art, the utility model provides a casing pressure balance sleeve having the following features:

[0019] Beneficial effects:

[0020] 1. The utility model pumps fracturing fluid into the interior of the first casing to form high pressure, and the fracturing fluid can fracture the formation rock here through the first fracturing hole; then, the first sealing ball is put into the interior of the first casing and the fracturing fluid is pumped, and when the first sealing ball moves to the position of the convex limit ring, the first sliding sleeve can be effectively sealed, and as the fracturing fluid is continuously pumped in, the pressure inside the first casing also increases accordingly, and then when the pressure reaches a certain critical value, the first sealing ball and the first sliding sleeve can be pushed to slide inside the first sliding groove, and the first sliding sleeve can immediately expose the second fracturing hole and seal the first fracturing hole, and then the fracturing fluid can fracture the formation rock here through the second fracturing hole, thereby effectively improving the fracturing efficiency and success rate.

[0021] 2. The utility model puts the second sealing ball into the interior of the second casing and pumps fracturing fluid. When the second sealing ball moves to the position of the four elastic limit blocks, the second sleeve can be effectively sealed. As the fracturing fluid is continuously pumped in, the pressure inside the second casing increases accordingly. Then, when the pressure reaches a certain critical value, the second sealing ball and the second sleeve can be pushed to slide inside the second slide groove. As the second sleeve moves, the third fracturing hole can be exposed. Then, the fracturing fluid can fracture the formation rock here through the second fracturing hole. At the same time, when the four elastic limit blocks are completely moved to the interior of the limit groove, they can move outward respectively. At this time, the second sealing ball can pass through here and continue to move to the right. Therefore, different numbers of second casings, second sleeves and other parts can be connected according to different construction lengths or depths. The second sealing ball can seal and fracture them in turn, thereby improving the overall practicality and work efficiency of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional schematic diagram of the structure of the utility model;

[0023] Figure 2 It is a front cross-sectional schematic diagram of the first sleeve and other parts of the structure of the utility model;

[0024] Figure 3 It is a three-dimensional schematic diagram of the second sliding sleeve and other parts of the structure of the utility model;

[0025] Figure 4 It is a front cross-sectional schematic diagram of the second sleeve and other parts of the utility model structure.

[0026] Among them: 1. first casing; 2. first fracturing hole; 3. second fracturing hole; 4. first slide groove; 5. first sleeve; 6. first blocking ball; 7. connecting pipe; 8. second casing; 9. third fracturing hole; 10. second slide groove; 11. limiting groove; 12. second sleeve; 13. second blocking ball; 14. elastic limiting block; 15. convex limiting ring; 16. guide block. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] See also Figure 1-4A casing pressure balancing sleeve comprises a first casing 1, a first fracturing hole 2 and a second fracturing hole 3 are formed on the outer side of the first casing 1, a first sliding groove 4 is formed inside the first casing 1, a first sliding sleeve 5 is slidably installed inside the first sliding groove 4, a first blocking ball 6 is installed inside the first sliding sleeve 5, a connecting pipe 7 is fixedly connected to the left end of the first casing 1, a second casing 8 is fixedly connected to the left end of the connecting pipe 7, a third fracturing hole 9 is formed on the outer side of the second casing 8, a second sliding groove 10 and a limiting groove 11 are formed inside the second casing 8, a second sliding sleeve 12 is slidably installed inside the second sliding groove 10, a second blocking ball 13 is installed inside the second sliding sleeve 12, and an elastic limiting block 14 is fixedly installed on the right end of the second sliding sleeve 12.

[0029] Specifically, the number of the first fracturing holes 2, the second fracturing holes 3 and the third fracturing holes 9 are all four. The advantage is that by pumping fracturing fluid into the first casing 1 and the second casing 8 and forming high pressure, the fracturing fluid can respectively pass through the first fracturing holes 2, the second fracturing holes 3 and the third fracturing holes 9 to break the formation rock and generate cracks, thereby effectively improving the development efficiency of oil and gas resources, and the first fracturing holes 2, the second fracturing holes 3 and the third fracturing holes 9 at different locations can not only effectively increase the production of oil and gas wells, but also form a continuous artificial fracture network, improve fracturing efficiency, and reduce costs.

[0030] Specifically, a convex stop ring 15 is provided near the left end of the first sleeve 5, the diameter of the first blocking ball 6 is larger than the inner diameter of the convex stop ring 15, and the first sleeve 5 is installed near the right end inside the first casing 1. The advantage is that by pumping fracturing fluid into the first casing 1 and forming high pressure, the fracturing fluid can fractur the formation rock here through the first fracturing hole 2; then the first blocking ball 6 is put into the first casing 1 and the fracturing fluid is pumped, and when the first blocking ball 6 moves to the position of the convex stop ring 15, the first sleeve 5 can be effectively blocked, and as the fracturing fluid is continuously pumped in, the pressure inside the first casing 1 also increases, and then when the pressure reaches a certain critical value, the first blocking ball 6 and the first sleeve 5 can be pushed to slide inside the first chute 4, and the first sleeve 5 can then expose the second fracturing hole 3 and block the first fracturing hole 2, and then the fracturing fluid can fractur the formation rock here through the second fracturing hole 3, thereby effectively improving the fracturing efficiency and success rate.

[0031] Specifically, a guide block 16 is provided near the left end of the second sliding sleeve 12. The advantage is that, through this structure, when the first blocking ball 6 or the second blocking ball 13 is dropped from the inside of the second casing 8, the guide block 16 can play a good guiding role, and at the same time, when the fracturing fluid is pumped in, it can also be ensured to move along a predetermined path, thereby ensuring a stable environment inside the pipe and maintaining pressure balance in the device.

[0032] Specifically, there are four elastic limit blocks 14, which are closely connected to each other inside the second slide groove 10, and the inner diameter of the limit groove 11 is slightly larger than the inner diameter of the second slide groove 10, and the diameter of the second blocking ball 13 is slightly larger than the inner diameter formed by the four elastic limit blocks 14. The advantage is that, through this structure, after the rock fracturing at the second fracturing hole 3 is completed, the second blocking ball 13 can be put in, and at the same time, the fracturing fluid can be pumped into the second casing 8. When the second blocking ball 13 moves to the position of the four elastic limit blocks 14, the second sleeve 12 can be effectively blocked. With the continuous pumping of the fracturing fluid, the pressure inside the second casing 8 also increases. After that, when the pressure reaches a certain critical value, the second blocking ball 13 and the second sleeve 12 can be pushed to slide inside the second slide groove 10. As the second sleeve 12 moves The third fracturing hole 9 can be exposed, and then the fracturing fluid can pass through the second fracturing hole 3 to fracture the formation rock here. At the same time, when the four elastic limit blocks 14 are completely moved to the inside of the limit groove 11, they can move outward respectively. At this time, the second sealing ball 13 can pass through here and continue to move to the right. Therefore, different numbers of second casings 8 and second sliding sleeves 12 and other parts can be connected according to different construction lengths or depths. The second sealing ball 13 can seal and fracture them in turn, thereby improving the overall practicality and work efficiency of the device.

[0033] Specifically, the diameter of the first blocking ball 6 is smaller than the inner diameter formed by the four elastic limit blocks 14. The advantage is that the first blocking ball 6 can be put into the first sleeve 1 through the second sleeve 8 and the connecting pipe 7, so the first blocking ball 6 can directly pass through the four elastic limit blocks 14 and move to the inside of the first sliding sleeve 5, which improves the overall practicality of the device and ensures the normal operation of the whole.

[0034] When in use, by pumping fracturing fluid into the interior of the first casing 1 and forming high pressure, the fracturing fluid can fracture the formation rock here through the first fracturing hole 2; then, the first sealing ball 6 is put into the interior of the first casing 1 and the fracturing fluid is pumped. When the first sealing ball 6 moves to the position of the convex limit ring 15, the first sleeve 5 can be effectively sealed. As the fracturing fluid is continuously pumped in, the pressure inside the first casing 1 also increases. Then, when the pressure reaches a certain critical value, the first sealing ball 6 and the first sleeve 5 can be pushed to slide inside the first slide groove 4. The first sleeve 5 can then expose the second fracturing hole 3 and seal the first fracturing hole 2. Then, the fracturing fluid can fracture the formation rock here through the second fracturing hole 3, thereby effectively improving the fracturing efficiency and success rate; by putting the second sealing ball 13 into the interior of the second casing 8 and pumping the fracturing fluid, the second sealing ball 13 When it moves to the position of the four elastic limit blocks 14, the second sleeve 12 can be effectively sealed. As the fracturing fluid is continuously pumped in, the pressure inside the second casing 8 also increases. Then, when the pressure reaches a certain critical value, the second sealing ball 13 and the second sleeve 12 can be pushed to slide inside the second slide groove 10. As the second sleeve 12 moves, the third fracturing hole 9 can be exposed. Then, the fracturing fluid can fracture the formation rock here through the second fracturing hole 3. At the same time, when the four elastic limit blocks 14 are completely moved to the inside of the limit groove 11, they can move outward respectively. At this time, the second sealing ball 13 can pass through here and continue to move to the right. Therefore, different numbers of second casings 8 and second sleeves 12 and other parts can be connected according to different construction lengths or depths, and the second sealing ball 13 can seal and fracture them in turn, thereby improving the overall practicality and work efficiency of the device.

[0035] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A casing pressure balancing sleeve, comprising a first casing (1), characterized in that: The first casing (1) has a first fracturing hole (2) and a second fracturing hole (3) formed on its outer side surface, a first sliding groove (4) formed inside the first casing (1), a first sliding sleeve (5) slidably mounted inside the first sliding groove (4), a first blocking ball (6) mounted inside the first sliding sleeve (5), a connecting pipe (7) fixedly connected to the left end of the first casing (1), a second casing (8) fixedly connected to the left end of the connecting pipe (7), a third fracturing hole (9) formed on the outer side surface of the second casing (8), a second sliding groove (10) and a limiting groove (11) formed inside the second casing (8), a second sliding sleeve (12) slidably mounted inside the second sliding groove (10), a second blocking ball (13) mounted inside the second sliding sleeve (12), and an elastic limiting block (14) fixedly mounted on the right end of the second sliding sleeve (12).

2. The casing pressure balancing sleeve according to claim 1, characterized in that: The number of the first fracturing hole (2), the second fracturing hole (3) and the third fracturing hole (9) is four.

3. The casing pressure balancing sleeve according to claim 1, characterized in that: A convex limiting ring (15) is arranged near the left end inside the first sliding sleeve (5), the diameter of the first blocking ball (6) is larger than the inner diameter of the convex limiting ring (15), and the first sliding sleeve (5) is installed inside the first sleeve (1) near the right end.

4. The casing pressure balancing sleeve according to claim 1, characterized in that: A guide block (16) is provided inside the second sliding sleeve (12) near the left end.

5. The casing pressure balancing sleeve according to claim 1, characterized in that: The number of the elastic limit blocks (14) is four, and the four elastic limit blocks (14) are closely connected to each other inside the second slide groove (10), and the inner diameter of the limit groove (11) is larger than the inner diameter of the second slide groove (10), and the diameter of the second blocking ball (13) is larger than the inner diameter formed by the four elastic limit blocks (14).

6. The casing pressure balancing sleeve according to claim 1, characterized in that: The diameter of the first blocking ball (6) is smaller than the inner diameter formed by the four elastic limiting blocks (14).

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