Fracturing method for improving crack complexity by using stress interference

Abstract

The invention relates to the technical field of oil reservoir reconstruction, and discloses a fracturing method for improving crack complexity by using stress interference, which comprises the following steps: determining a perforation cluster unit sequence based on crack spacing in a perforation cluster; based on the perforation cluster unit sequence, determining a fracturing operation sequence of the perforation cluster; and on the basis of the fracturing operation sequence of the perforation cluster, corresponding fracturing operation is completed in sequence. According to the technical scheme, the complexity of cracks in the horizontal well can be improved, the reservoir transformation volume is maximized, and finally the purpose of improving the final recoverable reserves of a single well is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil reservoir reconstruction, in particular to a fracturing method for improving fracture complexity by stress interference. BACKGROUND

[0002] With the rapid development of global economy, energy, as the driving force and basic element of economic growth, is becoming increasingly important. In recent years, the proportion of development of unconventional oil and gas resources such as tight oil in the energy industry has gradually increased, and the number of producing wells has also increased. The staged volume fracturing technology of horizontal wells has been widely used in unconventional reservoirs.

[0003] The staged volume fracturing technology of horizontal wells is an effective means to form a complex fracture network in unconventional reservoirs. During the fracturing process, the induced stress and fracture propagation reduce the difference between the two stresses and increase the complexity of artificial fractures, which is beneficial to improve the long-term effective conductivity of the reservoir and thus improve the economic development benefit.

[0004] In order to maximize the volume of reservoir reconstruction and improve the complexity of fractures, and to realize the efficient development of oil-rich areas, the present application provides a new horizontal well staged fracturing method. SUMMARY

[0005] To solve the above problems, the present application provides a fracturing method for improving fracture complexity by stress interference, which can improve the complexity of fractures in horizontal wells, maximize the volume of reservoir reconstruction, and ultimately improve the ultimate recoverable reserves of single wells.

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

[0007] The present application provides a fracturing method for improving fracture complexity by stress interference, comprising:

[0008] Determining a perforation cluster unit sequence based on the fracture spacing within the perforation cluster;

[0009] Determining a fracturing operation sequence of the perforation cluster based on the perforation cluster unit sequence;

[0010] Based on the fracturing operation sequence of the perforation cluster, the corresponding fracturing operation is completed in sequence.

[0011] Further, based on the fracture spacing within the perforation cluster, the perforation cluster unit sequence is determined, comprising:

[0012] Based on the direction from the toe end to the heel end of the horizontal well, the perforation cluster is marked as a perforation cluster sequence from small to large;

[0013] Based on the maximum cluster number of the perforation cluster unit and the fracture spacing within the perforation cluster, the perforation cluster unit sequence is determined.

[0014] Further, based on the sequence of the perforation cluster unit, the sequence of the fracturing operation of the perforation cluster is determined, comprising:

[0015] Based on the sequence number of the sequence of the perforation cluster unit, the fracturing operation order of the perforation cluster unit is determined;

[0016] Based on the sequence number of the perforation cluster in the perforation cluster unit, the fracturing operation order of the perforation cluster in the perforation cluster unit is determined by inserting the sequence;

[0017] Based on the fracturing operation order of the perforation cluster unit and the fracturing operation order of the perforation cluster in the perforation cluster unit, the fracturing operation sequence of all perforation clusters in the sequence of the perforation cluster unit is determined.

[0018] Further, based on the sequence of the fracturing operation of the perforation cluster, before sequentially completing the corresponding fracturing operation, it further comprises: passing through the well to the fracturing position corresponding to the first fracturing operation in the sequence of the fracturing operation of the perforation cluster.

[0019] Further, based on the sequence of the fracturing operation of the perforation cluster, sequentially completing the corresponding fracturing operation, comprising:

[0020] Lower the fracturing tool string into the fracturing position corresponding to the first fracturing operation in the sequence of the fracturing operation of the perforation cluster in the well;

[0021] Using the technology of hydraulic sandblasting perforation, the perforation operation corresponding to the first fracturing operation is completed;

[0022] Using the technology of annular sand fracturing, the fracturing operation corresponding to the first fracturing operation is completed;

[0023] The fracturing tool string is pulled up to the position corresponding to the next fracturing operation corresponding to the first fracturing operation, and the fracturing operation corresponding to the sequence of the fracturing operation of the perforation cluster is sequentially completed.

[0024] Further, based on the sequence of the fracturing operation of the perforation cluster, sequentially completing the corresponding fracturing operation, further comprising:

[0025] Based on the construction curve trend, it is judged whether the fracturing position corresponding to the fracturing operation of the perforation cluster is communicated with the formation, if the formation is communicated, the sand plug is actively created;

[0026] Based on the construction curve trend, the corresponding relationship between the displacement and the pressure is determined;

[0027] Based on the corresponding relationship between the displacement and the pressure, it is judged whether the sand plug is effective, if it is effective, the fracturing operation of the perforation cluster is executed.

[0028] Further, the fracturing tool string comprises:

[0029] Coiled tubing, coiled tubing connector, safety joint, upper centralizer, hydraulic lance, lower centralizer, packer, casing coupling positioner, guide shoe.

[0030] Further, the fracturing tool string is lowered into the well into the fracturing operation sequence of the perforation cluster, and after the fracturing position corresponding to the first fracturing operation, the steps further include:

[0031] The fracturing tool string is positioned to the fracturing position corresponding to the first fracturing operation by using a collar locator, and the setting and sealing are performed by using a packer.

[0032] Further, based on the fracturing operation sequence of the perforation cluster, the steps of sequentially completing the corresponding fracturing operation further include:

[0033] The fracturing fluid is injected into the coiled tubing to perform the positive well washing, and when no sand returns to the ground, an annular volume is positively washed out for annular pressure control.

[0034] Further, based on the fracturing operation sequence of the perforation cluster, the steps of sequentially completing the corresponding fracturing operation further include:

[0035] The fracturing tool is pulled out of the well to complete the completion operation.

[0036] To sum up, the technical scheme provided by the application has at least the following technical effects or advantages:

[0037] The method is based on the continuous tubing bottom seal drag hydraulic sandblasting perforation staged fracturing process, adopts a "cell division + sequence insertion" mode to change the fracturing reconstruction order, and uses stress interference mechanism and artificial sand plugging technology to provide a competitive advantage for full reconstruction of the hydraulic fracture, thereby reducing the two-way stress difference, improving the fracture complexity in the horizontal well, maximizing the reservoir reconstruction volume, and ultimately achieving the purpose of improving the ultimate recoverable reserves of a single well.

[0038] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent to those skilled in the art from the description, or can be learned by practice of the present application. The objects and other advantages of the present application can be realized and achieved by the structures indicated in the specification, claims and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0040] Figure 1 It is a flowchart of a fracturing method for improving fracture complexity by using stress interference in an embodiment of the present application;

[0041] Figure 2 A schematic diagram for a distance between a next perforation cluster and a previous perforation cluster in a perforation cluster unit in an embodiment of the present application being greater than 1-1.5 times of a fracture spacing in the perforation cluster;

[0042] Figure 3 A schematic diagram for a distance between a next perforation cluster and a previous perforation cluster in a perforation cluster unit in an embodiment of the present application being less than 1-1.5 times of a fracture spacing in the perforation cluster;

[0043] Figure 4 A schematic diagram for a scenario of a fracturing operation sequence of perforation clusters in a horizontal well in an embodiment of the present application;

[0044] Figure 5 A schematic diagram for another scenario of a fracturing operation sequence of perforation clusters in a horizontal well in an embodiment of the present application. DETAILED DESCRIPTION

[0045] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0046] Figure 1 A flowchart of a fracturing method for improving fracture complexity by using stress interference in an embodiment of the present application is shown in the figure. The fracturing method for improving fracture complexity by using stress interference includes:

[0047] S101, determining a perforation cluster unit sequence based on a fracture spacing in a perforation cluster;

[0048] For example, determining the perforation cluster unit sequence based on the fracture spacing in the perforation cluster includes:

[0049] Based on a direction from a toe end to a heel end of the horizontal well, marking the perforation clusters as a perforation cluster sequence from small to large;

[0050] Determining the perforation cluster unit sequence based on a maximum cluster number of the perforation cluster unit and the fracture spacing in the perforation cluster.

[0051] S102, determining a fracturing operation sequence of the perforation clusters based on the perforation cluster unit sequence;

[0052] For example, determining the fracturing operation sequence of the perforation clusters based on the perforation cluster unit sequence includes:

[0053] Determining a fracturing operation sequence of the perforation cluster unit based on a sequence number of the perforation cluster unit sequence.

[0054] determining the fracturing operation sequence of the perforation cluster based on the fracturing operation sequence of the perforation cluster unit and the fracturing operation sequence of the perforation cluster in the perforation cluster unit.

[0055] determining the fracturing operation sequence of the perforation cluster based on the fracturing operation sequence of the perforation cluster unit and the fracturing operation sequence of the perforation cluster in the perforation cluster unit.

[0056] S103, sequentially completing the corresponding fracturing operation based on the fracturing operation sequence of the perforation cluster.

[0057] Exemplarily, before sequentially completing the corresponding fracturing operation based on the fracturing operation sequence of the perforation cluster, it further includes: passing through the well to the fracturing position corresponding to the first fracturing operation in the fracturing operation sequence of the perforation cluster.

[0058] Exemplarily, sequentially completing the corresponding fracturing operation based on the fracturing operation sequence of the perforation cluster includes:

[0059] lowering the fracturing tool string into the fracturing position corresponding to the first fracturing operation in the fracturing operation sequence of the perforation cluster;

[0060] completing the perforation operation corresponding to the first fracturing operation by using the hydraulic sandblasting perforation technology;

[0061] completing the fracturing operation corresponding to the first fracturing operation by using the annular sand fracturing technology;

[0062] lifting the fracturing tool string to the position corresponding to the next fracturing operation corresponding to the first fracturing operation, and sequentially completing the fracturing operation corresponding to the fracturing operation sequence of the perforation cluster.

[0063] Exemplarily, sequentially completing the corresponding fracturing operation based on the fracturing operation sequence of the perforation cluster further includes:

[0064] judging whether the fracturing position corresponding to the fracturing operation of the perforation cluster communicates with the formation based on the change trend of the construction curve, and if the formation has been communicated, actively creating a sand plug;

[0065] determining the corresponding relationship between the displacement and the pressure based on the change trend of the construction curve;

[0066] judging whether the sand plug is effective based on the corresponding relationship between the displacement and the pressure, and if effective, performing the fracturing operation of the perforation cluster.

[0067] Exemplarily, the fracturing tool string includes:

[0068] coiled tubing, coiled tubing connector, safety joint, upper centralizer, hydraulic lance, lower centralizer, packer, casing coupling positioner, guide shoe.

[0069] Exemplarily, after the fracturing tool string is lowered into the well into the fracturing operation sequence of the perforation cluster, the first fracturing operation corresponding to the fracturing position, further comprising:

[0070] The fracturing tool string is positioned to the fracturing position corresponding to the first fracturing operation by using a collar locator, and the setting and checking of the packer are performed.

[0071] Exemplarily, based on the fracturing operation sequence of the perforation cluster, the steps of sequentially completing the corresponding fracturing operation further comprise:

[0072] The fracturing fluid is injected into the coiled tubing for positive well washing, and when no sand returns to the ground, an annular volume is positively washed out for annular pressure control.

[0073] Exemplarily, based on the fracturing operation sequence of the perforation cluster, the steps of sequentially completing the corresponding fracturing operation further comprise:

[0074] The fracturing tool is pulled out of the well to complete the completion operation.

[0075] The technical scheme of the present application is further illustrated below in combination with an actual operation scene, and the specific steps are as follows:

[0076] (1) Preparation before fracturing: based on the direction from the toe end to the heel end of the horizontal well, all the perforation clusters in the well are marked as the first, second, third, fourth,..., N clusters, and the sequence of all the perforation clusters is obtained. The maximum cluster number of the perforation cluster is determined to be 3, and the perforation cluster sequence is divided into units according to the maximum cluster number. The first, second and third clusters in the perforation cluster sequence are divided into a perforation cluster unit 1. The distance between the fourth cluster and the third cluster (the previous cluster) is determined, and if the distance is greater than 1-1.5 times the fracture spacing in the perforation cluster, the fourth, fifth and sixth clusters are divided into a perforation cluster unit 2 (as shown in Figure 2 Figure 3 ​The unit division rule is that, according to the distance between the next perforation cluster of the current perforation cluster unit and the previous perforation cluster, and the size relationship between the fracture spacing in the perforation cluster, the next perforation cluster unit is divided. Based on the unit division rule, all perforation clusters in the perforation cluster sequence are divided into units to obtain the perforation cluster unit sequence corresponding to the perforation cluster sequence, that is, the perforation cluster unit sequence including the perforation cluster unit 1, the perforation cluster unit 2, …, and the perforation cluster unit M. According to the sequence number of the perforation cluster unit sequence, the fracturing operation sequence of the perforation cluster unit is determined, that is, the perforation cluster unit 1→the perforation cluster unit 2→the perforation cluster unit 3…→the perforation cluster unit M. Based on the sequence number of the perforation cluster in the perforation cluster unit, the fracturing operation sequence of the perforation cluster in the perforation cluster unit is determined by using the insertion sequence, such as the fracturing operation sequence of the perforation cluster in the perforation cluster unit 1 being 1-①→1-③→1-②, the fracturing operation sequence of the perforation cluster in the perforation cluster unit 2 being 2-⑤→2-④ or the fracturing operation sequence of the perforation cluster in the perforation cluster unit 2 being 2-④→2-⑥→2-⑤, and so on. Based on the fracturing operation sequence of the perforation cluster unit and the fracturing operation sequence of the perforation cluster in the perforation cluster unit, the fracturing operation sequence of all perforation clusters in the perforation cluster unit sequence is determined, as shown in 2. When the distance between the next perforation cluster (the fourth cluster) of the perforation cluster unit 1 and the previous perforation cluster (the third cluster) is greater than 1-1.5 times the fracture spacing in the perforation cluster, the fracturing operation sequence of the perforation clusters corresponding to the perforation cluster unit 1 and the perforation cluster unit 2 is 1-①→1-③→1-②→2-④→2-⑥→2-⑤; when the distance is less than or equal to 1-1.5 times the fracture spacing in the perforation cluster, the fracturing operation sequence of the perforation clusters corresponding to the perforation cluster unit 1 and the perforation cluster unit 2 is 1-①→1-③→1-②→2-⑤→2-④. 1-① represents the first perforation cluster in the perforation cluster unit 1, that is, the sequence number of the perforation cluster unit-sequence number of the perforation cluster.

[0077] (2) Wellbore circulation: Circulate the wellbore to the fracturing location.

[0078] (3) Connect the tool string: Fix the coiled tubing, the coiled tubing connector, the safety joint, the upper centralizer, the hydraulic jet gun, the lower centralizer, the packer, the casing collar locator, and the guide shoe together from top to bottom to form the fracturing tool string.

[0079] (4) Run the coiled tubing: Run the coiled tubing into the well to the designed depth, calibrate the depth, position the casing collar locator to the perforation location, set the packer, and check the setting.

[0080] (5) Coiled tubing hydraulic sandblasting perforation operation: Establish circulation, perform coiled tubing hydraulic sandblasting perforation, throttle through the nozzle to change the high-pressure perforation fluid in the tubing into a high-speed jet to perforate the casing and the cement sheath, and communicate the channel between the reservoir and the wellbore. When sandblasting perforation, the tubing-casing annulus is open to the ground or throttled to be open, the coiled tubing injects displacement fluid, and the perforation operation is completed.

[0081] (6) Implement annular sand fracturing: Inject preflush, sand-carrying fluid and displacement fluid from the tubing-casing annulus between the fracturing string and the casing to fracture and open the formation to form a fracture, and continuously inject fracturing fluid through the coiled tubing to balance the pressure difference between the double-cluster fracturing string and the tubing-casing annulus during the fracturing process, thereby completing the fracturing operation, i.e., completing the first-1-① cluster operation.

[0082] (7) Repeat the operation to complete the operation construction: Raise the coiled tubing to the next cluster operation position and make the packer switch tracks to achieve unblocking, repeat steps (4)-(6) to complete the first-1-③ cluster operation.

[0083] (8) Raise and unblock: Raise the coiled tubing to unblock, and after passing through the first-1-③ cluster fracture position, position the coupling locator to the preset position between the first-1-③ cluster and the first-1-① cluster, and set the packer.

[0084] (9) Well washing: Inject clean water into the casing at a large flow rate, and reverse circulation to wash the well until the inlet and outlet water quality are consistent.

[0085] (10) Test squeeze and determine liquid inflow: The construction curve trend determines the current communication between the first-1-③ cluster and the formation, and the corresponding relationship between the displacement and the pressure is obtained to provide a basis for subsequent judgment.

[0086] (11) Artificial sand plugging: Use the fine control of sand and liquid added by the coiled tubing to plug the modified fracture, and if the first-1-③ cluster is determined to have communicated with the formation in step (10), use the "small scale + small displacement + under displacement" construction mode to create a sand plug. If the formation is not communicated, directly execute steps (4)-(6) to complete the operation.

[0087] (12) Determine the effect of artificial sand plugging: Test squeeze and combine the corresponding relationship between the construction displacement and the pressure in step (10). When the displacement is less than 0.5 cubic meters, the pressure rises to the upper limit of the pressure limit, which is a preliminary judgment of sand plugging (adjusted according to the site construction situation). If the plugging is not effective, steps (11) can be repeated multiple times until the plugging is determined to be effective.

[0088] (13) Coiled tubing positive washing: Switch to the positive well washing process, and inject fracturing fluid through the coiled tubing for positive well washing. Observe the surface liquid and sand production, and when there is no sand return, wash another annulus volume and control the annulus pressure.

[0089] (14) Repeat the operation to complete the operation construction: Repeat steps (4)-(6) to complete the first-1-② cluster operation.

[0090] (15) Reverse washing of the tubing-casing annulus: After the coiled tubing pump is stopped, inject clean water from the tubing to wash out the remaining sand through the annulus, and calculate the sand and liquid volume to provide a basis for subsequent construction.

[0091] (16) Repeat the operation to complete the remaining unit construction: after the fracturing operation is completed, the coiled tubing is pulled up to make the packer switch tracks to realize unblocking, from the 4th cluster, if the distance from the previous cluster (1st-3rd cluster) is ≤ 1-1.5 times the distance between the fractures, then repeat steps (4)-(15) to perform unit 2 construction; if the distance from the previous cluster (1st-3rd cluster) is > 1-1.5 times the distance between the fractures, then repeat steps (4)-(6) and then immediately perform steps (8)-(15) to perform unit 2 construction, until all fracturing operations are completed.

[0092] (17) Completion: after the construction of all sections, the coiled tubing is pulled out, and the well is completed.

[0093] Figure 4 A schematic diagram of one scenario of the fracturing operation sequence of the perforation cluster in the horizontal well in the embodiment of the present application is shown in the figure, which is divided into 1st, 2nd, 3rd, 4th... clusters from the toe end to the heel end of the horizontal well, from the 4th cluster, if the distance from the previous cluster (1st-3rd cluster) is > 1-1.5 times the distance between the fractures, as shown in the figure, the 1st, 2nd, 3rd clusters are divided into unit 1, the 4th, 5th clusters are combined with the 3rd cluster of the previous unit 1 to be regarded as unit 2, the 6th, 7th clusters are combined with the 5th cluster of the previous unit 2 to be regarded as unit 3, and so on, that is, the operation sequence is 1-1→1-3→1-2→2-4→2-6→2-5→3-7→3-9→3-8. Figure 1

[0094] A schematic diagram of another scenario of the fracturing operation sequence of the perforation cluster in the horizontal well in the embodiment of the present application is shown in the figure, which is divided into 1st, 2nd, 3rd, 4th... clusters from the toe end to the heel end of the horizontal well, from the 4th cluster, if the distance from the previous cluster (1st-3rd cluster) is ≤ 1-1.5 times the distance between the fractures, as shown in the figure, the 1st, 2nd, 3rd clusters are divided into unit 1, the 3rd cluster of the previous unit 1 and the 4th, 5th clusters are combined to be regarded as unit 2, the 5th cluster of the previous unit 2 and the 6th, 7th clusters are combined to be regarded as unit 3, and so on, that is, the operation sequence is 1-1→1-3→1-2→2-5→2-4→2-7→2-6→3-9→3-8. Figure 5 Figure 2

[0095] In summary, the technical scheme provided by the present application has at least the following technical effects or advantages:

[0096] The method is based on the continuous tubing with bottom seal drag hydraulic sandblasting perforation staged fracturing process, adopts the mode of "unit cell division + sequence insertion" to change the fracturing transformation sequence, and utilizes the stress interference mechanism and the artificial sand plugging technology to provide a competitive advantage for the full transformation of the hydraulic fracture, thereby reducing the two-way stress difference, improving the complexity of the fractures in the horizontal well, maximizing the reservoir transformation volume, and ultimately achieving the purpose of improving the ultimate recoverable reserves of a single well.

[0097] ​​Additional features and advantages of the present application will be set forth in the description that follows, and in part will be apparent from the description, or can be learned by practice of the present application. The objectives and other advantages of the present application will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

[0098] Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood that modifications can be made to the foregoing embodiments, and that such modifications are intended to fall within the scope of the embodiments. Additionally, although specific terminology has been employed by way of example, the use of such terms is meant to be taken in an extremely broad sense, and is not intended to limit the present application.

Claims

1. A fracturing method that utilizes stress disturbance to increase the complexity of fractures, characterized in that, include: The perforation cluster unit sequence is determined based on the crack spacing within the perforation cluster; Based on the perforation cluster unit sequence, the fracturing operation sequence of the perforation cluster is determined; Based on the fracturing operation sequence of the perforation cluster, the corresponding fracturing operations are completed sequentially.

2. The fracturing method for increasing crack complexity by utilizing stress interference according to claim 1, characterized in that, The determination of the perforation cluster unit sequence based on the crack spacing within the perforation cluster includes: Based on the direction from the toe to the heel of the horizontal well, the perforation clusters are marked as a sequence of perforation clusters from smallest to largest; The perforation cluster unit sequence is determined based on the maximum number of perforation clusters contained in the perforation cluster unit and the crack spacing within the perforation cluster.

3. The fracturing method for increasing crack complexity by utilizing stress interference according to claim 2, characterized in that, The step of determining the fracturing operation sequence of the perforation cluster based on the perforation cluster unit sequence includes: The fracturing operation sequence of the perforation cluster unit is determined based on the sequence number of the perforation cluster unit sequence; Based on the sequence number of the perforation clusters in the perforation cluster unit, the fracturing operation order of the perforation clusters in the perforation cluster unit is determined by interpolation. Based on the fracturing operation sequence of the perforation cluster unit and the fracturing operation sequence of the perforation clusters in the perforation cluster unit, the fracturing operation sequence of all perforation clusters in the perforation cluster unit sequence is determined.

4. The fracturing method for increasing crack complexity by utilizing stress interference according to claim 1, characterized in that, Before the fracturing operation sequence based on the perforation cluster completes the corresponding fracturing operations in sequence, it also includes: the fracturing position corresponding to the first fracturing operation in the fracturing operation sequence from wellbore to the perforation cluster.

5. The fracturing method for increasing crack complexity by utilizing stress interference according to claim 1, characterized in that, The fracturing operation sequence based on the perforation cluster sequentially completes the corresponding fracturing operations, including: The fracturing tool string is lowered into the fracturing operation sequence of the perforation cluster in the well, and the fracturing position corresponding to the first fracturing operation is as follows: The perforation operation corresponding to the first fracturing operation was completed by using water jet perforation technology. The fracturing operation corresponding to the first fracturing operation was completed by using annular sand fracturing technology; The fracturing tool string is raised to the position corresponding to the next fracturing operation corresponding to the first fracturing operation, and the fracturing operations corresponding to the fracturing operation sequence of the perforation cluster are completed in sequence.

6. The fracturing method for increasing fracture complexity by utilizing stress interference according to claim 5, characterized in that, The fracturing operation sequence based on the perforation cluster, which sequentially completes the corresponding fracturing operations, further includes: Based on the trend of the construction curve, determine whether the fracturing location corresponding to the fracturing operation of the perforation cluster is connected to the formation. If it is connected to the formation, actively create sand plugs. Based on the trend of the construction curve, the corresponding relationship between displacement and pressure is determined; Based on the relationship between displacement and pressure, it is determined whether the sand plug is effective. If it is effective, the fracturing operation of the perforation cluster is performed.

7. The fracturing method for increasing fracture complexity by utilizing stress interference according to claim 5, characterized in that, The fracturing tool string includes: Coiled tubing, coiled tubing connectors, safety joints, upper centralizers, hydraulic spray guns, lower centralizers, packers, casing couplings, and guide shoes.

8. The fracturing method for increasing fracture complexity by utilizing stress interference according to claim 7, characterized in that, The fracturing operation sequence of running the fracturing tool string into the perforation cluster in the well, after the fracturing position corresponding to the first fracturing operation, further includes: The coupling locator is used to position the fracturing tool string to the fracturing position corresponding to the first fracturing operation, and the packer is used for setting and verifying the seal.

9. The fracturing method for increasing fracture complexity by utilizing stress interference according to claim 7, characterized in that, The fracturing operation sequence based on the perforation cluster, which sequentially completes the corresponding fracturing operations, further includes: Fracturing fluid is injected into the coiled tubing for forward well washing. When no sand returns to the surface, an annulus volume is created during forward washing for annulus pressure control.

10. The fracturing method for increasing fracture complexity by utilizing stress interference according to claims 7-9, characterized in that, The fracturing operation sequence based on the perforation cluster, which sequentially completes the corresponding fracturing operations, further includes: The fracturing tool is then retrieved from the well to complete the well completion operation.

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