Perforation parameter optimization method and system for realizing in-section equilibrium transformation

Abstract

The invention provides a perforation parameter optimization method and system for realizing in-section equilibrium transformation, and belongs to the technical field of petroleum and natural gas development. The method comprises the following steps: establishing a fracturing model by adopting a Petri-Kinex geological engineering integration method, and calculating the crack propagation resistance difference between perforation clusters; calculating perforation friction based on the corrected perforation throttling model; according to the hole friction resistance value, multiple fracturing sections are selected, and multiple sets of perforation schemes are arranged in a crossed mode; an eagle eye test is carried out, and the perforation scheme corresponding to the minimum hole erosion difference of all perforation clusters in the fracturing section serves as the optimal perforation scheme; construction is carried out according to the optimal perforation scheme, and the distribution proportion of each perforation sand cluster fluid is monitored in real time through outside-pipe optical fibers by means of sound wave inversion; and synchronous crack initiation and balanced liquid feeding of the perforation clusters are ensured according to the preset gradient lift displacement. According to the method, the perforation scheme can be optimized, the construction displacement can be determined, synchronous crack initiation and balanced expansion of the multiple perforation clusters in the section are achieved, and reservoir oil and gas resources are utilized to the maximum extent.

Description

Technical Field

[0001] The invention relates to the technical field of oil and natural gas development, and in particular to a perforation parameter optimization method and system for realizing intra-segment balanced transformation. Background Art

[0002] For staged fracturing of horizontal sections in conglomerate reservoirs, it is very important to determine the reasonable number of single cluster perforations. On the one hand, it can prevent the perforations from being excessively eroded by proppants, causing single fracture advance; on the other hand, it can make full use of the perforation throttling friction, overcome the mechanical differences between clusters within the section, and achieve synchronous fracturing and balanced expansion.

[0003] However, in the actual fracturing process, due to the large-scale proppant erosion, the perforation flow limiting effect gradually weakened, resulting in the root crack expansion degree being much greater than the toe crack expansion degree, and the final balanced transformation degree was not ideal. In addition, in order to fully cut the reservoir, multiple perforation clusters (5-10 clusters / segment) are arranged in a single fracturing section. The smaller the cluster spacing, the greater the inter-fracture interference stress, resulting in multiple fractures that cannot be uniformly filled with fluid. The horizontal section of the tight sandstone reservoir has strong heterogeneity and stress interference. Conventional flow limiting fracturing cannot balance the differences between perforation clusters. For this reason, some scholars have proposed extreme flow limiting fracturing technology to reduce the total number of holes and maintain high displacement. By reducing the number of perforations or reducing the perforation diameter, a larger perforation friction is generated, balancing the inter-fracture interference and inter-cluster expansion resistance between fractures, thereby balancing the fluid inflow between each perforation cluster. Therefore, determining a reasonable number of perforations in a single cluster is crucial for reservoir transformation using flow limiting fracturing technology.

[0004] The existing technology has at least the following deficiencies:

[0005] 1. During the continuous sand addition process, the perforation erosion causes the perforation throttling friction to gradually decrease, and the flow limiting effect is weakened. The perforation throttling model currently used in the perforation parameter optimization does not consider the influence of perforation erosion, and the optimized perforation parameters cannot achieve balanced liquid inflow between clusters within the segment.

[0006] 2. Existing perforation parameter optimization is mostly based on indoor tests and theoretical calculations, which are difficult to verify in the fracturing field test. The present invention uses the external fiber optic monitoring technology to record the fluid inflow of each perforation cluster in real time for actual fracturing wells, verify the rationality of the perforation parameters, and guide on-site promotion. Summary of the invention

[0007] To solve the problems existing in the prior art, the purpose is to provide a method for optimizing the number of perforations based on Hawkeye test and fiber optic monitoring, which can accurately and effectively determine the number of perforations in a single cluster of flow-limiting fracturing to ensure that there is sufficient perforation friction to balance the inter-fracture interference and inter-cluster expansion resistance between fractures, thereby achieving balanced fluid inflow between each perforation cluster.

[0008] The present invention provides a perforation parameter optimization method for realizing intra-segment balanced transformation, comprising the following steps:

[0009] Step 1: Use the Petrel-Kinetix geological engineering integration method to establish a fracturing model and calculate the difference in fracture propagation resistance between each perforation cluster in the fracturing section;

[0010] Step 2: Based on the modified perforation throttling model, the perforation friction resistance is calculated to ensure that the perforation friction resistance is greater than the difference in fracture extension resistance between clusters, wherein the dynamic changes of the perforation diameter and the flow coefficient under the influence of the sand volume, the perforation flow velocity and the sand concentration are considered, and based on the perforation throttling model without considering erosion, the proppant concentration and the pumping time are introduced into the perforation throttling model without considering erosion, so as to obtain the modified perforation throttling model;

[0011] Step 3: For the same experimental well, select multiple fracturing stages according to the perforation friction value and cross-arrange multiple perforation schemes;

[0012] Step 4: After the sand addition is completed, the Hawkeye test is carried out to count the diameters of the erosion of the holes in each perforation cluster in the experimental fracturing section, and the perforation scheme corresponding to the smallest difference in erosion of the holes in each perforation cluster in the fracturing section is taken as the optimal perforation scheme;

[0013] Step 5: For new wells in the same block, the optimal perforation scheme is used for construction, and the sand and liquid distribution ratio of each perforation cluster is monitored in real time by using acoustic wave inversion through the optical fiber outside the pipe;

[0014] Step 6: Increase the displacement with a preset gradient to ensure that each perforation cluster starts to fracture synchronously and the difference in liquid inflow rate between clusters is less than 30%, and determine the optimal perforation plan and its corresponding construction displacement.

[0015] Preferably, the Petrel-Kinetix geological engineering integration method is used to establish a fine fracturing model, and the difference in crack propagation resistance between each perforation cluster in the fracturing section is calculated. Specifically, a geological model is established by Petrel, a fracturing crack propagation model is established by Kinetix, and the established fracturing crack propagation model is used to calculate the difference in crack propagation resistance between each perforation cluster in the fracturing section.

[0016] Preferably, the perforation throttling model without considering erosion adopts a pressure drop model based on the Bernoulli equation, which is expressed as:

[0017]

[0018] In the formula,

[0019] Δp perf is the hole throttling drop, Pa;

[0020] P1 and P2 are the pressures before and after the perforation cluster, Pa;

[0021] ρ is the density of fracturing fluid, g / cm 3 ;

[0022] n p is the number of perforations in a single perforation cluster;

[0023] D p , is the perforation diameter, m;

[0024] C d is the perforation discharge coefficient;

[0025] Q is the flow rate through the perforation, m 3 / s.

[0026] Preferably, the dynamic changes of the perforation diameter and the flow coefficient under the influence of the sand amount, the perforation flow velocity and the sand concentration are considered, and the proppant concentration and the pumping time are introduced into the perforation throttling model without considering the erosion based on the perforation throttling model without considering the erosion, so as to obtain the following dynamic change equation of the perforation diameter and the dynamic change equation of the flow coefficient included in the modified perforation throttling model:

[0027] Dynamic change formula of perforation diameter:

[0028]

[0029] Dynamic change formula of flow coefficient:

[0030]

[0031] In the formula,

[0032] C prop is the proppant mass concentration, kg / m 3 ;

[0033] α and β are the erosion coefficients related to the perforation diameter and discharge coefficient, respectively;

[0034] v is the hole flow velocity, m / s;

[0035] C d is the perforation discharge coefficient;

[0036] C max d is the maximum discharge coefficient of perforation.

[0037] Preferably, α = 9.8 × 10 -14 , β=9.48×10 -10 . Determined by the laboratory, it can be calibrated to other values.

[0038] Preferably, C max d It is 0.60~0.90.

[0039] Preferably, in step three, for the same experimental well, 9 or 12 fracturing stages are selected according to the borehole friction resistance value, and 3 sets of perforation schemes are cross-arranged.

[0040] Preferably, in the perforation scheme, the number of holes in a single cluster is not less than 2, and the interval between holes is 2-4.

[0041] Preferably, a single fracturing stage has six clusters, and a single cluster has 3, 5 and 8 perforations respectively.

[0042] Preferably, in step six, the preset gradient is 2m 3 / min liter displacement.

[0043] The present invention provides a perforation parameter optimization system for realizing intra-segment balanced transformation, and the perforation parameter optimization system for realizing intra-segment balanced transformation executes the steps of any of the above-mentioned perforation parameter optimization methods for realizing intra-segment balanced transformation.

[0044] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0045] 1. The perforation number optimization method based on Hawkeye test and optical fiber monitoring of the present invention can reasonably optimize the number of single cluster perforations, and can avoid excessive erosion of the perforations by proppants, resulting in single seam advance;

[0046] 2. The present invention utilizes the friction resistance of the hole throttling to overcome the mechanical differences between clusters within a segment and achieve synchronous initiation and balanced expansion of cracks within the segment. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A flow chart of a method for optimizing perforation parameters for achieving intra-segment balanced transformation according to an embodiment of the present invention;

[0048] Figure 2 : is a comparison diagram of the hole areas after erosion of various perforation clusters according to an embodiment of the present invention. The numbers on the horizontal axis in the figure represent the fracturing stage numbers, and each fracturing stage is the first cluster, the second cluster, the third cluster, the fourth cluster, the fifth cluster, and the sixth cluster from left to right. The results show that the single cluster 8-hole solution is better than the single cluster 5-hole and the single cluster 3-hole, and the single cluster 8-hole is recommended as the optimal solution.

[0049] Figure 3 (a) is a waterfall diagram of a single-segment 6-cluster real-time liquid inflow monitoring result according to an embodiment of the present invention, and (b) is a waterfall diagram of a single-segment 5-cluster real-time liquid inflow monitoring result according to an embodiment of the present invention; wherein the abscissa is time and the ordinate is depth (m);

[0050] Figure 4 This is a flow chart of a method for optimizing perforation parameters for achieving intra-segment balanced transformation according to yet another embodiment of the present invention. DETAILED DESCRIPTION

[0051] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings.

[0052] The present invention provides a perforation parameter optimization method for realizing intra-segment balanced transformation, comprising the following steps:

[0053] Step 1: Use the Petrel-Kinetix geological engineering integration method to establish a fracturing model and calculate the difference in fracture propagation resistance between each perforation cluster in the fracturing section;

[0054] Step 2: Based on the modified perforation throttling model, the perforation friction resistance is calculated to ensure that the perforation friction resistance is greater than the difference in fracture extension resistance between clusters, wherein the dynamic changes of the perforation diameter and the flow coefficient under the influence of the sand volume, the perforation flow velocity and the sand concentration are considered, and based on the perforation throttling model without considering erosion, the proppant concentration and the pumping time are introduced into the perforation throttling model without considering erosion, so as to obtain the modified perforation throttling model;

[0055] Step 3: For the same experimental well, select multiple fracturing stages according to the perforation friction value and cross-arrange multiple perforation schemes;

[0056] Step 4: After the sand addition is completed, the Hawkeye test is carried out to count the diameters of the erosion of the holes in each perforation cluster in the experimental fracturing section, and the perforation scheme corresponding to the smallest difference in erosion of the holes in each perforation cluster in the fracturing section is taken as the optimal perforation scheme;

[0057] Step 5: For new wells in the same block, the optimal perforation scheme is used for construction, and the sand and liquid distribution ratio of each perforation cluster is monitored in real time by using acoustic wave inversion through the optical fiber outside the pipe;

[0058] Step 6: Increase the displacement with a preset gradient to ensure that each perforation cluster starts to fracture synchronously and the difference in liquid inflow rate between clusters is less than 30%, and determine the optimal perforation plan and its corresponding construction displacement.

[0059] According to a specific embodiment of the present invention, the Petrel-Kinetix geological engineering integration method is used to establish a fine fracturing model, and the difference in crack propagation resistance between each perforation cluster in the fracturing section is calculated. Specifically, a geological model is established by Petrel, a fracturing crack propagation model is established by Kinetix, and the established fracturing crack propagation model is used to calculate the difference in crack propagation resistance between each perforation cluster in the fracturing section.

[0060] According to a specific embodiment of the present invention, the perforation throttling model without considering erosion adopts a pressure drop model based on the Bernoulli equation, which is expressed as:

[0061]

[0062] In the formula,

[0063] Δp perf is the hole throttling drop, Pa;

[0064] P1 and P2 are the pressures before and after the perforation cluster, Pa;

[0065] ρ is the density of fracturing fluid, g / cm 3 ;

[0066] n p is the number of perforations in a single perforation cluster;

[0067] D p , is the perforation diameter, m;

[0068] C d is the perforation discharge coefficient;

[0069] Q is the flow rate through the perforation, m 3 / s.

[0070] According to a specific embodiment of the present invention, the dynamic changes of the perforation diameter and the flow coefficient under the influence of the sand amount, the perforation flow velocity and the sand concentration are considered, and the proppant concentration and the pumping time are introduced into the perforation throttling model without considering the erosion based on the perforation throttling model without considering the erosion, so as to obtain the following dynamic change equation of the perforation diameter and the dynamic change equation of the flow coefficient included in the modified perforation throttling model:

[0071] Dynamic change formula of perforation diameter:

[0072]

[0073] Dynamic change formula of flow coefficient:

[0074]

[0075] In the formula,

[0076] C prop is the proppant mass concentration, kg / m 3 ;

[0077] α and β are the erosion coefficients related to the perforation diameter and discharge coefficient, respectively;

[0078] v is the hole flow velocity, m / s;

[0079] C d is the perforation discharge coefficient;

[0080] C max d is the maximum discharge coefficient of perforation.

[0081] According to a specific embodiment of the present invention, α=9.8×10 -14, β=9.48×10 -10 . Determined by the laboratory, it can be calibrated to other values.

[0082] According to a specific embodiment of the present invention, C max d It is 0.60~0.90.

[0083] According to a specific implementation of the present invention, in step three, for the same experimental well, 9 or 12 fracturing stages are selected according to the borehole friction value, and 3 sets of perforation schemes are cross-arranged.

[0084] According to a specific embodiment of the present invention, in the perforation scheme, the number of holes in a single cluster is not less than 2, and the interval between the holes is 2-4.

[0085] According to a specific embodiment of the present invention, a single fracturing stage has six clusters, and a single cluster has 3, 5 and 8 perforations respectively.

[0086] According to a specific embodiment of the present invention, in step six, the preset gradient 2m 3 / min liter displacement.

[0087] The present invention provides a perforation parameter optimization system for realizing intra-segment balanced transformation, and the perforation parameter optimization system for realizing intra-segment balanced transformation executes the steps of any of the above-mentioned perforation parameter optimization methods for realizing intra-segment balanced transformation.

[0088] Example 1

[0089] According to a specific implementation scheme of the present invention, the perforation parameter optimization method for realizing intra-segment balanced transformation of the present invention is described in detail below.

[0090] The present invention provides a perforation parameter optimization method for realizing intra-segment balanced transformation, comprising the following steps:

[0091] Step 1: Use the Petrel-Kinetix geological engineering integration method to establish a fracturing model and calculate the difference in fracture propagation resistance between each perforation cluster in the fracturing section;

[0092] Step 2: Based on the modified perforation throttling model, the perforation friction resistance is calculated to ensure that the perforation friction resistance is greater than the difference in fracture extension resistance between clusters, wherein the dynamic changes of the perforation diameter and the flow coefficient under the influence of the sand volume, the perforation flow velocity and the sand concentration are considered, and based on the perforation throttling model without considering erosion, the proppant concentration and the pumping time are introduced into the perforation throttling model without considering erosion, so as to obtain the modified perforation throttling model;

[0093] Step 3: For the same experimental well, select multiple fracturing stages according to the perforation friction value and cross-arrange multiple perforation schemes;

[0094] Step 4: After the sand addition is completed, the Hawkeye test is carried out to count the diameters of the erosion of the holes in each perforation cluster in the experimental fracturing section, and the perforation scheme corresponding to the smallest difference in erosion of the holes in each perforation cluster in the fracturing section is taken as the optimal perforation scheme;

[0095] Step 5: For new wells in the same block, the optimal perforation scheme is used for construction, and the sand and liquid distribution ratio of each perforation cluster is monitored in real time by using acoustic wave inversion through the optical fiber outside the pipe;

[0096] Step 6: Increase the displacement with a preset gradient to ensure that each perforation cluster starts to fracture synchronously and the difference in liquid inflow rate between clusters is less than 30%, and determine the optimal perforation plan and its corresponding construction displacement.

[0097] Example 2

[0098] According to a specific implementation scheme of the present invention, the perforation parameter optimization method for realizing intra-segment balanced transformation of the present invention is described in detail below.

[0099] The present invention provides a perforation parameter optimization method for realizing intra-segment balanced transformation, comprising the following steps:

[0100] Step 1: Use the Petrel-Kinetix geological engineering integration method to establish a fracturing model and calculate the difference in fracture propagation resistance between each perforation cluster in the fracturing section;

[0101] Step 2: Based on the modified perforation throttling model, the perforation friction resistance is calculated to ensure that the perforation friction resistance is greater than the difference in fracture extension resistance between clusters, wherein the dynamic changes of the perforation diameter and the flow coefficient under the influence of the sand volume, the perforation flow velocity and the sand concentration are considered, and based on the perforation throttling model without considering erosion, the proppant concentration and the pumping time are introduced into the perforation throttling model without considering erosion, so as to obtain the modified perforation throttling model;

[0102] Step 3: For the same experimental well, select multiple fracturing stages according to the perforation friction value and cross-arrange multiple perforation schemes;

[0103] Step 4: After the sand addition is completed, the Hawkeye test is carried out to count the diameters of the erosion of the holes in each perforation cluster in the experimental fracturing section, and the perforation scheme corresponding to the smallest difference in erosion of the holes in each perforation cluster in the fracturing section is taken as the optimal perforation scheme;

[0104] Step 5: For new wells in the same block, the optimal perforation scheme is used for construction, and the sand and liquid distribution ratio of each perforation cluster is monitored in real time by using acoustic wave inversion through the optical fiber outside the pipe;

[0105] Step 6: Increase the displacement with a preset gradient to ensure that each perforation cluster starts to fracture synchronously and the difference in liquid inflow rate between clusters is less than 30%, and determine the optimal perforation plan and its corresponding construction displacement.

[0106] Among them, the Petrel-Kinetix geological engineering integration method is used to establish a fine fracturing model, and the difference in crack extension resistance between each perforation cluster in the fracturing section is calculated. Specifically, the geological model is established by Petrel, the fracturing crack extension model is established by Kinetix, and the established fracturing crack extension model is used to calculate the difference in crack extension resistance between each perforation cluster in the fracturing section.

[0107] Among them, the perforation throttling model without considering erosion adopts the pressure drop model based on the Bernoulli equation, which is expressed as:

[0108]

[0109] In the formula,

[0110] Δp perf is the hole throttling drop, Pa;

[0111] P1 and P2 are the pressures before and after the perforation cluster, Pa;

[0112] ρ is the density of fracturing fluid, g / cm 3 ;

[0113] n p is the number of perforations in a single perforation cluster;

[0114] D p , is the perforation diameter, m;

[0115] C d is the perforation discharge coefficient;

[0116] Q is the flow rate through the perforation, m 3 / s.

[0117] Among them, the dynamic changes of the perforation diameter and the flow coefficient under the influence of the sand amount, the perforation flow velocity and the sand concentration are considered. Based on the perforation throttling model without considering erosion, the proppant concentration and the pumping time are introduced into the perforation throttling model without considering erosion, and the following dynamic change equations of the perforation diameter and the flow coefficient included in the modified perforation throttling model are obtained:

[0118] Dynamic change formula of perforation diameter:

[0119]

[0120] Dynamic change formula of flow coefficient:

[0121]

[0122] In the formula,

[0123] C prop is the proppant mass concentration, kg / m3 ;

[0124] α and β are the erosion coefficients related to the perforation diameter and discharge coefficient, respectively;

[0125] v is the hole flow velocity, m / s;

[0126] C d is the perforation discharge coefficient;

[0127] C max d is the maximum discharge coefficient of perforation.

[0128] Where α = 9.8 × 10 -14 , β=9.48×10 -10 . Determined by the laboratory, it can be calibrated to other values.

[0129] Among them, C max d It is 0.60~0.90.

[0130] Among them, in step three, for the same experimental well, 9 or 12 fracturing stages are selected according to the borehole friction resistance value, and 3 sets of perforation schemes are cross-arranged.

[0131] Among them, in the perforation plan, the number of holes in a single cluster is not less than 2, and the interval between the holes is 2-4.

[0132] Among them, there are six clusters in a single fracturing stage, and the number of perforations in a single cluster are 3, 5 and 8 respectively.

[0133] Among them, in step 6, with the preset gradient of 2m 3 / min liter displacement.

[0134] Example 3

[0135] According to a specific implementation scheme of the present invention, the perforation parameter optimization method for realizing intra-segment balanced transformation of the present invention is described in detail below.

[0136] This embodiment uses a specific application scenario as an example to illustrate the implementation plan of this specification.

[0137] A typical horizontal well A in a certain place was selected, and a comparative test was carried out on the 7th to 15th sections (9 fracturing sections) of well A. The 9 fracturing sections were all designed as a single section with 6 clusters. Figure 1 As shown, the following steps are included:

[0138] Implement the fracturing and perforating plan. After the sand is added to each fracturing stage, a reduction test is performed to obtain the wellhead pumping pressure data under different perforating parameters. By analyzing the step reduction test data, the wellhead pressure characteristics under different perforating parameters can be clarified, and the number of perforations can be optimized to give full play to the flow limiting effect, obtain the ideal initial friction resistance of the perforation, and avoid single-slit advance caused by excessive erosion of the perforation.

[0139] Based on the Hawkeye monitoring method, 360° ring scanning technology was used to take photos of the eroded holes in each fracturing stage, and then the hole area after erosion of each perforation cluster was counted. It can be seen intuitively that when the number of perforations in a single cluster is 8, the overall erosion amount of the 9th, 12th and 15th sections is relatively balanced, indicating that a good transformation effect has been achieved, verifying that a single cluster of 8 holes is a suitable perforation scheme.

[0140] A typical well B of a conglomerate reservoir in a certain place was selected. Combined with the external fiber optic monitoring technology, two fracturing sections of well B were selected. Six perforation clusters were arranged in the 11th section, and five perforation clusters were arranged in the 14th section. A single cluster of 8 holes perforation scheme was adopted. The acoustic wave signal generated by the liquid inflow of each cluster was obtained in real time through the external fiber optic cable. The liquid inflow signal of each cluster was analyzed to invert the liquid inflow of each cluster to verify that the single cluster of 8 holes can fully play the role of limiting flow, realize balanced liquid inflow and balanced expansion of the fractures in the section, and avoid single fracture advance caused by excessive erosion of the perforations.

[0141] Table 1 Three sets of perforation schemes for nine fracturing stages selected for the experimental well

[0142]

[0143] Table 1 shows three sets of perforation schemes for nine fracturing stages preferred in the experimental well in this embodiment.

[0144] Figure 2 In this embodiment, based on the Hawkeye monitoring method, 360° ring scanning technology is used to take pictures of the eroded holes in each fracturing stage, and then a comparison chart of the hole areas after erosion of various perforation clusters is counted; the results show that the single cluster 8 holes scheme is better than the single cluster 5 holes and the single cluster 3 holes, and the single cluster 8 holes is recommended as the optimal scheme;

[0145] Figure 3 (a) is the method based on fiber optic monitoring in this embodiment, which obtains the acoustic wave signal generated by the liquid inflow of each cluster in real time through the optical fiber outside the tube, inverts the liquid inflow amount of each cluster, and obtains a waterfall chart of the real-time liquid inflow monitoring results of a single segment of 6 clusters. (b) is the method based on fiber optic monitoring in the embodiment, which obtains the acoustic wave signal generated by the liquid inflow of each cluster in real time through the optical fiber outside the tube, inverts the liquid inflow amount of each cluster, and obtains a waterfall chart of the real-time liquid inflow monitoring results of a single segment of 5 clusters.

[0146] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A perforation parameter optimization method for achieving intra-segment balanced transformation, characterized in that: The steps include: Step 1: Use the Petrel-Kinetix geological engineering integration method to establish a fracturing model and calculate the difference in fracture propagation resistance between each perforation cluster in the fracturing section; Step 2: Based on the modified perforation throttling model, the perforation friction resistance is calculated to ensure that the perforation friction resistance is greater than the difference in fracture extension resistance between clusters, wherein the dynamic changes of the perforation diameter and the flow coefficient under the influence of the sand volume, the perforation flow velocity and the sand concentration are considered, and based on the perforation throttling model without considering erosion, the proppant concentration and the pumping time are introduced into the perforation throttling model without considering erosion, so as to obtain the modified perforation throttling model; Step 3: For the same experimental well, select multiple fracturing stages according to the perforation friction value and cross-arrange multiple perforation schemes; Step 4: After the sand addition is completed, the Hawkeye test is carried out to count the diameters of the erosion of the holes in each perforation cluster in the experimental fracturing section, and the perforation scheme corresponding to the smallest difference in erosion of the holes in each perforation cluster in the fracturing section is taken as the optimal perforation scheme; Step 5: For new wells in the same block, the optimal perforation scheme is used for construction, and the sand and liquid distribution ratio of each perforation cluster is monitored in real time by using acoustic wave inversion through the optical fiber outside the pipe; Step 6: Increase the displacement with a preset gradient to ensure that each perforation cluster starts to fracture synchronously and the difference in liquid inflow rate between clusters is less than 30%, and determine the optimal perforation plan and its corresponding construction displacement.

2. The perforation parameter optimization method for achieving intra-segment balanced transformation according to claim 1, characterized in that: The Petrel-Kinetix geological engineering integration method is used to establish a fine fracturing model, and the difference in crack propagation resistance between each perforation cluster in the fracturing section is calculated. Specifically, a geological model is established by Petrel, a fracturing crack propagation model is established by Kinetix, and the established fracturing crack propagation model is used to calculate the difference in crack propagation resistance between each perforation cluster in the fracturing section.

3. The perforation parameter optimization method for achieving intra-segment balanced transformation according to claim 1, characterized in that: The perforation throttling model without considering erosion adopts the pressure drop model based on the Bernoulli equation, which is expressed as: In the formula, Δp perf is the hole throttling drop, Pa; P1 and P2 are the pressures before and after the perforation cluster, Pa; ρ is the density of fracturing fluid, g / cm 3 ; n p is the number of perforations in a single perforation cluster; D p , is the perforation diameter, m; C d is the perforation discharge coefficient; Q is the flow rate through the perforation, m 3 / s.

4. The perforation parameter optimization method for achieving intra-segment balanced transformation according to claim 3 is characterized in that: Considering the dynamic changes of the perforation diameter and the flow coefficient under the influence of the sand amount, the perforation flow velocity and the sand concentration, the proppant concentration and the pumping time are introduced into the perforation throttling model without considering the erosion based on the perforation throttling model without considering the erosion, and the following dynamic change equations of the perforation diameter and the flow coefficient included in the modified perforation throttling model are obtained: Dynamic change formula of perforation diameter: Dynamic change formula of flow coefficient: In the formula, C prop is the proppant mass concentration, kg / m 3 ; α and β are the erosion coefficients related to the perforation diameter and discharge coefficient, respectively; v is the hole flow velocity, m / s; C d is the perforation discharge coefficient; C max d is the maximum discharge coefficient of perforation.

5. The perforation parameter optimization method for achieving intra-segment balanced transformation according to claim 4 is characterized in that: α＝9.8×10 -14 ，β＝9.48×10 -10 。 6. The perforation parameter optimization method for achieving intra-segment balanced transformation according to claim 1, characterized in that: C max d It is 0.60~0.

90.

7. The perforation parameter optimization method for achieving intra-segment balanced transformation according to claim 1, characterized in that: In step three, for the same experimental well, 9 or 12 fracturing stages were selected according to the borehole friction value, and 3 sets of perforation schemes were cross-arranged.

8. The perforation parameter optimization method for achieving intra-segment balanced transformation according to claim 7, characterized in that: In the perforation scheme, the number of holes in a single cluster shall not be less than 2, and the interval between holes shall be 2-4.

9. The perforation parameter optimization method for achieving intra-segment balanced transformation according to claim 8, characterized in that: There are six clusters in a single fracturing stage, and the number of perforations in a single cluster is 3, 5, and 8, respectively.

10. The perforation parameter optimization method for realizing intra-segment balanced transformation according to claim 1, characterized in that: It is characterized in that In step 6, the preset gradient is 2m 3 / min liter displacement.

11. A perforation parameter optimization system for realizing intra-segment balanced transformation, characterized in that: The perforation parameter optimization system for achieving intra-segment balanced transformation executes the steps of the perforation parameter optimization method for achieving intra-segment balanced transformation according to any one of claims 1 to 10.

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