Post-compression evaluation method, electronic device and storage medium

Abstract

The present invention proposes a post-pressure evaluation method, electronic equipment and medium. The post-pressure analysis method includes: calculating the friction resistance P along the perforation well‑perf and the friction coefficient α along the perforation path; determine the minimum value of the gradient of the friction coefficient λ along the perforation path min ; Calculate the perforation friction coefficient ζ at the instant when the pump is stopped in each fracturing stage n and perforation friction P perf‑n ; According to the change of construction pressure before and after the temporary plugging ball plugging of the nth fracturing stage, calculate the plugging efficiency η of the temporary plugging ball perforation n This method can provide real-time evaluation of the post-pressure effect of temporary plugging by ball throwing at the hydraulic fracturing construction site, and provide a theoretical basis and technical support for the subsequent optimization of the ball throwing scheme.

Description

Technical Field

[0001] The invention belongs to the field of oil and gas field development, and in particular relates to a post-fracturing evaluation method, electronic equipment and storage medium for evaluating the plugging effect of a temporary plugging ball for horizontal well fracturing. Background Art

[0002] Horizontal well segmented cluster fracturing technology is one of the key technologies to achieve efficient development of tight oil and gas reservoirs. The results of on-site production profile monitoring show that only 20% to 40% of the fracturing clusters contribute to production, indicating that there is a serious phenomenon of non-uniform expansion of cracks in each cluster during the fracturing process.

[0003] Relevant research results show that factors such as reservoir heterogeneity and stress interference caused by multi-fracture expansion are important reasons for the non-uniform expansion of hydraulic fractures. Therefore, how to promote the balanced expansion of each cluster of fractures in the fracturing section and improve the hydraulic fracture coverage rate of the horizontal well section is a practical issue that deserves great attention. The ball-throwing temporary plugging process is currently widely used in multi-cluster fracturing of horizontal wells due to its advantages such as simple construction, low cost, and little reservoir damage. The temporary plugging ball seals the holes of the dominant expansion cluster to improve the uniform transformation of the horizontal section. Microseismic monitoring results also show that more rock fracture signals will be displayed after the ball is thrown.

[0004] At present, there is no method for evaluating the temporary plugging effect of throwing balls in the prior art, and there is a lack of relevant technical means. In engineering practice, the plugging effect of the plugging balls is roughly reflected mainly by the value of the pressure increase after throwing balls.

[0005] Since it is difficult to reasonably explain the effectiveness of the ball throwing effect in the actual construction process with the existing technology, there is a need in the art to establish a method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing. Summary of the invention

[0006] Aiming at the problem of evaluating the temporary plugging effect of ball throwing in the prior art, the present invention provides a post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing, which uses the actual pressure data of the fracturing construction site to quantitatively evaluate the plugging ratio of temporary plugging balls to perforations, thereby reflecting the plugging effect.

[0007] According to one aspect of the present invention, a post-fracturing evaluation method for evaluating the plugging effect of a temporary plugging ball in a horizontal well fracturing is provided, comprising:

[0008] Calculate the friction resistance along the perforation path P well-perf and along-the-perforation friction coefficient α;

[0009] Calculate the friction coefficient gradient λ along each fracturing stage n By comparing the friction coefficient gradient along the perforation, the minimum value λ is obtained min;

[0010] Calculate the perforation friction coefficient ζ at the instant of pump stop for fracturing in ball-dropping fracturing stage n n and perforation friction P perf-n ;

[0011] According to the change of temporary plugging ball plugging construction pressure, calculate the plugging efficiency η of the temporary plugging ball n .

[0012] Furthermore, the friction resistance P along the perforation can be calculated using the following formula: well-perf :

[0013] P well-perf =P(t p =0)-P(t p1 ) (1)

[0014] Among them, P(t p1 ) is the time when the friction resistance along the perforation disappears t p1 The corresponding pressure, P(t p =0) is the initial pressure corresponding to when the pump is stopped.

[0015] Furthermore, the friction coefficient α along the perforation can be calculated using the following formula:

[0016] α=P well-perf / Q 2 (2)

[0017] Among them, Q is the instantaneous displacement before the pump stops.

[0018] Furthermore, the following formula is used to calculate the friction coefficient gradient λ along the perforation of the nth fracturing stage of the horizontal well: n :

[0019] λ n =α n / H n (3)

[0020] Where n is the horizontal well fracturing stage number, 1≤n≤k; k is the total number of fracturing stages; α n is the friction coefficient along the perforation of the nth fracturing stage; H n is the depth measured in the middle of the nth fracturing stage, in m;

[0021] Based on the along-perforation friction coefficient gradient λ n Determine the minimum value of the friction coefficient gradient along the perforation min :

[0022] λ min =min(λ1,…,λ n ,…λ k ) (4)

[0023] Furthermore, the perforation friction coefficient ζ at the instant of pump stop in the nth fracturing stage can be calculated using the following formula: n :

[0024] ζ n =α n -H n λ x (5)

[0025] Wherein, based on the perforation friction coefficient ζ n Calculate the perforation friction P at the instant when the pump is stopped in the nth fracturing stage perf-n :

[0026] P perf-n =ζ n Q n 2 (6)

[0027] Among them, Q n It is the instantaneous displacement before pumping stops in the nth fracturing stage.

[0028] Furthermore, the pressure P(t p ) and pump stop time t p Data, obtain the pressure difference derivative curve;

[0029] Determine the time t at which the friction along the perforation disappears on the pressure difference derivative curve p1 And record the corresponding pressure P(t p1 ).

[0030] Furthermore, the plugging efficiency of the temporary plugging ball in the nth fracturing stage is η n is the ratio of the total number of temporary plugging balls to the number of plugged holes, that is:

[0031] η n =[N1 / (N1+N2)]×100% (7)

[0032] Among them, N1 is the number of perforations that were effectively filled with fluid before the ball was dropped in the nth fracturing stage but were blocked after the ball was dropped, and N2 is the number of perforations that were effectively filled with fluid before and after the ball was dropped in the nth fracturing stage.

[0033] Further,

[0034] N2=[AQ1 2 / (P perf Q3 3 / Q4 3 +P2-P3)] 0.5 (8)

[0035] N1=[AQ1 2 / (Pperf Q3 3 / Q4 3 +P1-P3)] 0.5 -[AQ1 2 / (P perf Q3 3 / Q4 3 +P2-P3)] 0.5 (9)

[0036] Substituting formula (8) and (9) into formula (7), we can obtain the efficiency of temporary plugging balls plugging perforations in the nth fracturing stage: n :

[0037] η n =1-[(P perf-n Q n-3 3 / Q n-4 3 +P n-1 -P n-3 ) / (P perf-n Q n-3 3 / Q n-4 3 +P n-2 -P n-3 )] 0.5 ×100%(10)

[0038] Among them, P1 is the average fracture extension pressure before the ball is thrown in the nth fracturing stage, MPa; Q1 is the injection displacement when the ball is thrown in the nth fracturing stage, MPa; P2 is the maximum instantaneous extension pressure after the ball is thrown in the nth fracturing stage, MPa; P3 is the average fracture extension pressure after the ball is thrown in, MPa; Q3 is the injection displacement after the ball is thrown in the nth fracturing stage, MPa; Q4 is the injection displacement at the instant when the pump is stopped in the nth fracturing stage, MPa; N1 is the number of perforations that are effectively filled with fluid before the ball is thrown in the nth fracturing stage but blocked after the ball is thrown; N2 is the number of perforations that are effectively filled with fluid before and after the ball is thrown in the nth fracturing stage; N3 is the number of new effective perforations that are filled with fluid after the ball is thrown in the nth fracturing stage.

[0039] According to another aspect of the present invention, there is provided an electronic device, the electronic device comprising:

[0040] A memory storing executable instructions;

[0041] A processor runs the executable instructions in the memory to implement the post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing.

[0042] According to another aspect of the present invention, a computer-readable storage medium is provided, which stores a computer program, and when the computer program is executed by a processor, the post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing is implemented.

[0043] The present invention provides a post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing. The method uses the actual pressure data of the fracturing construction site to quantitatively evaluate the plugging ratio of the temporary plugging balls to the perforations, thereby reflecting the plugging effect. The method can be used to conduct real-time evaluation of the post-fracturing effect of temporary plugging with balls at the hydraulic fracturing construction site, and provide a theoretical basis and technical support for the subsequent optimization of the ball throwing scheme. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components in the exemplary embodiments of the present disclosure.

[0045] Figure 1 The present invention is a flow chart of a post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing.

[0046] Figure 2 It is the second point data of the construction pressure curve according to an embodiment of the present invention.

[0047] Figure 3 Graph showing the pressure difference and the pressure difference derivative after the pump is stopped according to an embodiment of the present invention. DETAILED DESCRIPTION

[0048] The preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0049] like Figure 1 As shown, the post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing according to the present invention comprises:

[0050] Calculate the friction resistance along the perforation path P well-perf and along-the-perforation friction coefficient α;

[0051] Calculate the friction coefficient gradient λ along each fracturing stage n By comparing the friction coefficient gradient along the perforation, the minimum value λ is obtained min ;

[0052] Calculate the perforation friction coefficient ζ at the instant of pump stop for fracturing in ball-dropping fracturing stage n n and perforation friction P perf-n ;

[0053] According to the change of temporary plugging ball plugging construction pressure, calculate the plugging efficiency η of the temporary plugging ball n .

[0054] Preferably, the following formula can be used to calculate the perforation friction resistance P along the way: well-perf :

[0055] P well-perf = P(t p =0)- P(t p1 ) (1)

[0056] Among them, P(t p1 ) is the time when the friction resistance along the perforation disappears t p1 The corresponding pressure, P(t p =0) is the initial pressure corresponding to when the pump is stopped.

[0057] Specifically, the data of the pump stop time during fracturing construction can be selected for analysis, and the instantaneous displacement Q before the pump stop and the initial pressure value P (t p =0); the pump stop time is recorded as t p =0, according to the pressure P(t p ) and pump stop time t p Data, draw a double logarithmic pressure difference and its derivative graph, observe the time when the first "hump" peak appears on the double logarithmic pressure derivative curve (usually appears about one minute after the pump is stopped), and record the corresponding pressure P (t p1 ) and the appearance time t p1 , t p1 The time is the time when the friction along the perforation disappears.

[0058] Preferably, the displacement of each section during staged and clustered fracturing of horizontal wells is affected by the formation and the construction method, and there are differences in displacement. In order to eliminate the displacement difference, the friction coefficient α along the perforation is introduced. The friction coefficient α along the perforation can be calculated using the following formula:

[0059] α=P well-perf / Q 2 (2)

[0060] Among them, Q is the instantaneous displacement before the pump stops.

[0061] Preferably, in order to distinguish the along-perforation friction resistance into along-perforation friction resistance and perforation friction resistance, it is assumed that there is a section of perforation friction resistance in the horizontal well that can be approximated to 0, that is, the along-perforation friction resistance of this section is all along-perforation friction resistance. Then the along-perforation friction resistance coefficient gradient corresponding to the minimum value is the along-perforation friction resistance coefficient gradient, and the along-perforation friction resistance coefficient gradient λ of the nth fracturing section of the horizontal well can be calculated using the following formula n :

[0062] λ n =α n / H n (3)

[0063] Where n is the horizontal well fracturing stage number, 1≤n≤k; k is the total number of fracturing stages; α n is the friction coefficient along the perforation of the nth fracturing stage; H n It is the measured depth in the middle of the nth fracturing stage, in meters.

[0064] Based on the along-perforation friction coefficient gradient λ n Determine the minimum value of the friction coefficient gradient along the perforation min :

[0065] λ min =min(λ1,…,λ n ,…λ k ) (4)

[0066] Preferably, the perforation friction coefficient ζ at the instant when the pump is stopped in the nth fracturing stage can be calculated using the following formula: n :

[0067] ζ n =α n -H n λ min (5)

[0068] Wherein, based on the perforation friction coefficient ζ n Calculate the perforation friction P at the instant when the pump is stopped during fracturing of the nth fracturing stage perf-n :

[0069] P perf-n =ζ n Q n 2 (6)

[0070] Among them, Q n It is the instantaneous displacement before pumping stops in the nth fracturing stage.

[0071] Preferably, the plugging efficiency of the temporary plugging ball in the nth fracturing stage is η n is the ratio of the total number of temporary plugging balls to the number of plugged holes, that is:

[0072] η n =[N1 / (N1+N2)]×100% (7)

[0073] Among them, N1 is the number of perforations that were effectively filled with fluid before the ball was dropped in the nth fracturing stage but were blocked after the ball was dropped, and N2 is the number of perforations that were effectively filled with fluid before and after the ball was dropped in the nth fracturing stage.

[0074] N2=[AQ1 2 / (P perf Q3 3 / Q4 3 +P2-P3)] 0.5 (8)

[0075] N1=[AQ1 2 / (P perf Q3 3 / Q4 3 +P1-P3)] 0.5 -[AQ1 2 / (P perf Q3 3 / Q4 3 +P2-P3)] 0.5 (9)

[0076] Substituting formula (8) and (9) into formula (7), we can obtain the plugging efficiency of perforation holes in the nth fracturing stage: n :

[0077] η n =1-[(P perf Q3 3 / Q4 3 +P1-P3) / (P perf Q3 3 / Q4 3 +P2-P3)] 0.5 ×100% (10)

[0078] Among them, P1 is the average fracture extension pressure before the ball is thrown in the nth fracturing stage, MPa; Q1 is the injection displacement when the ball is thrown in the nth fracturing stage, MPa; P2 is the maximum instantaneous extension pressure after the ball is thrown in the nth fracturing stage, MPa; P3 is the average fracture extension pressure after the ball is thrown in, MPa; Q3 is the injection displacement after the ball is thrown in the nth fracturing stage, MPa; Q4 is the injection displacement at the instant when the pump is stopped in the nth fracturing stage, MPa; N1 is the number of perforations that are effectively filled with fluid before the ball is thrown in the nth fracturing stage but blocked after the ball is thrown; N2 is the number of perforations that are effectively filled with fluid before and after the ball is thrown in the nth fracturing stage; N3 is the number of new effective perforations that are filled with fluid after the ball is thrown in the nth fracturing stage.

[0079] The method of the present invention can utilize the actual pressure data of the hydraulic fracturing construction site to invert, analyze, and quantitatively evaluate the number of temporary plugging balls plugging the perforated holes, and then evaluate the plugging effect. The method can conduct real-time evaluation of the post-pressure effect of temporary plugging by throwing balls at the hydraulic fracturing construction site, and provide a theoretical basis and technical support for the subsequent optimization of the ball throwing scheme.

[0080] To facilitate understanding of the solutions and effects of the embodiments of the present invention, a specific application example is given below. Those skilled in the art should understand that the example is only for facilitating understanding of the present invention, and any specific details thereof are not intended to limit the present invention in any way.

[0081] Example 1

[0082] According to the post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing, the method comprises the following steps:

[0083] (1) The data of the pump stopping time during fracturing operation were selected for analysis, and the instantaneous displacement Q before the pump stopping and the initial pressure value P (t p =0), see Figure 2 ;

[0084] (2) The pump stop time is t p =0, according to the pressure P(t p ) and pump stop time t p Data, plot double logarithmic pressure difference and its derivative, see Figure 3 ;

[0085] (3) On the double logarithmic pressure derivative curve, observe the time when the first "hump" peak appears (usually about one minute after the pump is stopped) and record the corresponding pressure P (t p1 ) and the appearance time t p1 , t p1 The time is the time when the friction resistance along the perforation disappears;

[0086] (4) Calculation of the friction resistance P along the perforation well-perf

[0087] P well-perf =P(t p =0)-P(t p1 ) (1)

[0088] (5) During the staged and clustered fracturing of horizontal wells, the displacement of each section is affected by the formation and the construction method, and there are differences in displacement. In order to eliminate the displacement difference, the friction coefficient α along the perforation is introduced:

[0089] α=P well-perf / Q 2 (2)

[0090] (6) Calculate the friction coefficient gradient along the perforation of each fracturing stage, the friction coefficient gradient along the perforation of the nth fracturing stage λ n :

[0091] λ n =α n / H n (3)

[0092] Where n is the fracturing stage number, 1≤n≤k; k is the total number of fracturing stages; α n Explain the friction coefficient along the perforation for the nth fracturing stage; H n It is the measured depth in the middle of the nth fracturing stage, in meters.

[0093] (7) Find the fracturing section with the minimum value of the along-perforation friction coefficient gradient: In order to distinguish the along-perforation friction coefficient into along-perforation friction coefficient and perforation friction coefficient, it is assumed that there is a section of perforation friction coefficient in the horizontal well that can be approximated to 0, that is, the along-perforation friction coefficient gradient corresponding to the minimum value is the along-perforation friction coefficient gradient, and the minimum value of the along-perforation friction coefficient gradient λ min for:

[0094] λ min =min(λ1,…,λ n ,…λ k ) (4)

[0095] (8) Taking the ball-throwing fracturing stage n as an example, calculate the perforation friction coefficient ζ at the instant when the fracturing pump is stopped n ,

[0096] ζ n =α n -H n λ x (5)

[0097] (9) Taking ball-throwing fracturing stage n as an example, calculate the perforation friction P at the instant when the fracturing pump is stopped. perf-n ,

[0098] P perf-n =ζ n Q n 2 (6)

[0099] (10) According to the construction pressure change, establish the pressure change equation group:

[0100] P2-P1=AQ1 2 / N2 2 -AQ1 2 / (N1+N2) 2 (7)

[0101] P3-P1=AQ3 2 / (N2+N3) 2 -AQ1 2 / (N1+N2) 2 (8)

[0102] P perf =AQ4 2 / (N2+N3) 2 (9)

[0103] In the formula,

[0104] P1 is the average fracture extension pressure before the ball is dropped in the nth fracturing stage, MPa;

[0105] Q1 is the injection displacement when the ball is dropped in the nth fracturing stage, MPa;

[0106] P2 is the maximum instantaneous extension pressure after the ball is dropped in the nth fracturing stage, MPa;

[0107] P3 is the average fracture extension pressure after ball dropping in the nth fracturing stage, MPa;

[0108] Q3 is the injection displacement after the ball is dropped in the nth fracturing stage, MPa;

[0109] Q4 is the injection displacement at the instant when the pump is stopped in the nth fracturing stage, MPa;

[0110] N1 is the number of perforations that were effectively filled with fluid before the ball was dropped in the nth fracturing stage but were blocked after the ball was dropped, pieces;

[0111] N2 is the number of perforations that are effectively filled with fluid before and after the ball is dropped in the nth fracturing stage, pieces;

[0112] N3 is the number of new effective perforations after the ball is dropped in the nth fracturing stage.

[0113] Combining formulas (7) to (9), we can obtain

[0114] N2=[AQ1 2 / (P perf Q3 3 / Q4 3 +P2-P3)] 0.5 (10)

[0115] N1=[AQ1 2 / (P perf Q3 3 / Q4 3 +P1-P3)] 0.5 -[AQ1 2 / (P perf Q3 3 / Q43 +P2-P3)] 0.5 (11)

[0116] The efficiency η of plugging perforations by temporary plugging balls in the nth fracturing stage n is the ratio of the total number of temporary plugging balls to the number of plugged holes, that is:

[0117] η n =[N1 / (N1+N2)]×100% (12)

[0118] Substituting formula (10) and (11) into formula (12), we can obtain the calculation method of plugging efficiency:

[0119] η n =1-[(P perf Q3 3 / Q4 3 +P1-P3) / (P perf Q3 3 / Q4 3 +P2-P3)] 0.5 ×100% (13)

[0120] Example 2

[0121] This embodiment takes a shale gas horizontal well in the Sichuan Basin as an example. The horizontal well has a total of 20 fracturing stages, and collects and organizes the second-by-second data of the construction pressure of each stage of the well.

[0122] (1) First, taking the first section as an example, the data of the pump stop time during fracturing construction was selected for analysis. According to the data, the corresponding pressure value at the pump stop time was 55.34 MPa, and the instantaneous displacement before the pump stop was 14.1 m 3 / min.

[0123] (2) Taking the pump stop time as the origin (t p =0), according to the pressure P(t p ) and pump stop time t p Data, plot double logarithmic pressure and its derivative.

[0124] (3) On the double logarithmic pressure derivative curve, the first “hump” peak appears 34 seconds after the pump is stopped, and the corresponding pressure is 43.94 MPa, thus obtaining the along-perforation friction resistance P of the first stage of fracturing. well-perf-1 It is 11.4MPa.

[0125] (4) Repeat steps (1) to (3) to obtain the corresponding pressure value at the pump stop time, the instantaneous displacement before pump stop, and the along-perforation friction resistance of each fracturing stage. And calculate the along-perforation friction resistance coefficient based on the along-perforation friction resistance and the instantaneous displacement at the pump stop time, as shown in Table 1.

[0126] Table 1 Construction pressure curve

[0127]

[0128] (5) Count the depth measurement in the middle of each fracturing section and calculate the minimum value λ of the friction coefficient gradient along the perforation of each fracturing section min , see Table 2. It can be seen that the first section along the perforation friction coefficient gradient is the smallest, which is 1.019761×10 -5 Then, the along-perforation friction obtained by the first stage calculation is approximately equal to the along-perforation friction (the perforation friction is 0).

[0129] Table 2 Gradient of friction coefficient along the perforation in each section

[0130]

[0131]

[0132] (6) According to the friction resistance of the fracturing fluid obtained in the first stage, the friction coefficient along each fracturing stage is calculated, and then the friction coefficient ζ of each perforation stage is obtained. n , see Table 3.

[0133] Table 3 Friction coefficient of each perforation section

[0134] Segment number Friction coefficient along the perforation α Friction coefficient along the way η Perforation friction coefficient ζ 1 0.0573 0.0573 0 2 0.0926 0.0567 0.0359 3 0.1568 0.0559 0.1009 4 0.1010 0.0549 0.0461 5 0.2642 0.0541 0.2101 6 0.2369 0.0532 0.1837 7 0.2806 0.0525 0.2281 8 0.0872 0.0516 0.0356 9 0.0880 0.0516 0.0365 10 0.0736 0.0508 0.0228 11 0.1700 0.0499 0.1201 12 0.1108 0.0491 0.0617 13 0.0866 0.0484 0.0382 14 0.1284 0.0477 0.0807 15 0.1884 0.0469 0.1415 16 0.1329 0.0462 0.0867 17 0.1828 0.0454 0.1373 18 0.2152 0.0447 0.1705 19 0.0993 0.0440 0.0553 20 0.0494 0.0432 0.0062

[0135] (7) According to the pump stop displacement of each section, the instantaneous perforation friction resistance and friction resistance along the way at the time of pump stop of each fracturing section are obtained by comprehensive calculation, see Table 4.

[0136] Table 4 Summary of instantaneous fracturing friction interpretation results at each pump stop time

[0137]

[0138]

[0139] (8) For the fracturing sections that used ball-throwing temporary plugging (a total of 8 fracturing sections in the case study well used the ball-throwing temporary plugging technology), the total number of perforations in each section, the number of balls thrown, and the extension pressure and displacement before and after the ball-throwing were counted, as shown in Table 5 below.

[0140] Table 5 Statistics of the fracturing section with temporary plugging by ball throwing

[0141]

[0142] (9) The plugging efficiency of temporary plugging balls in each fracturing stage using temporary plugging balls was calculated, as shown in Table 6. The results show that the plugging ratio of effective liquid-inflow holes in each fracturing stage after ball throwing is 1.29% to 34.51%.

[0143] Table 6 Statistics on the efficiency of temporary plugging balls to plug perforations

[0144] Segment number Total number of perforations Number of pitches Temporary plugging ball plugging efficiency / % 10 39 22 28.55 11 39 24 15.39 12 36 18 12.58 13 36 20 34.51 14 36 20 12.29 15 36 20 17.13 16 36 42 1.29 18 36 20 10.35

[0145] Example 3

[0146] The present disclosure provides an electronic device, which includes: a memory storing executable instructions; a processor running the executable instructions in the memory to implement the above-mentioned post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing.

[0147] An electronic device according to an embodiment of the present disclosure includes a memory and a processor.

[0148] The memory is used to store non-temporary computer-readable instructions. Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc.

[0149] The processor may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of the present disclosure, the processor is used to run the computer-readable instructions stored in the memory.

[0150] Those skilled in the art should be able to understand that in order to solve the technical problem of how to obtain a good user experience, the present embodiment may also include well-known structures such as a communication bus and an interface, and these well-known structures should also be included in the protection scope of the present disclosure.

[0151] For detailed description of this embodiment, reference may be made to the corresponding descriptions in the aforementioned embodiments, which will not be repeated here.

[0152] Example 4

[0153] The embodiment of the present disclosure provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing is implemented.

[0154] According to the computer-readable storage medium of the embodiment of the present disclosure, non-transitory computer-readable instructions are stored thereon. When the non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the above-mentioned methods of each embodiment of the present disclosure are executed.

[0155] The above-mentioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or mobile hard disk), media with built-in rewritable non-volatile memory (e.g., memory card) and media with built-in ROM (e.g., ROM box).

[0156] Those skilled in the art should understand that the purpose of the above description of the embodiments of the present invention is only to exemplarily illustrate the beneficial effects of the embodiments of the present invention, and is not intended to limit the embodiments of the present invention to any given examples.

[0157] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing, characterized in that: include: Calculate the friction resistance P along each fracturing stage well-perf and along-the-perforation friction coefficient α; Calculate the friction coefficient gradient λ along each fracturing stage n By comparing the friction coefficient gradient along the perforation, the minimum value λ is obtained min ; Calculate the perforation friction coefficient ζ at the instant when the pump is stopped in each fracturing stage n and perforation friction P perf-n ; According to the change of temporary plugging ball plugging construction pressure, calculate the plugging efficiency η of the temporary plugging ball n ; According to the construction pressure change, the pressure change equation group is established. P2-P1=AQ1 2 / N2 2 -AQ1 2 / (N1+N2) 2 (7) <h2 style=";text-align:left;direction:ltr">P3-P1=AQ3<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> / (N2+N3)<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> -AQ1<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> / (N1+N2)<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> (8) P perf =AQ4 2 / (N2+N3) 2 (9) In the formula, P1 is the average fracture extension pressure before the ball is dropped in the nth fracturing stage, MPa; Q1 is the injection displacement when the ball is dropped in the nth fracturing stage, MPa; P2 is the maximum instantaneous extension pressure after the ball is dropped in the nth fracturing stage, MPa; P3 is the average fracture extension pressure after ball dropping in the nth fracturing stage, MPa; Q3 is the injection displacement after the ball is dropped in the nth fracturing stage, MPa; Q4 is the injection displacement at the instant when the pump is stopped in the nth fracturing stage, MPa; N1 is the number of perforations that were effectively filled with fluid before the ball was dropped in the nth fracturing stage but were blocked after the ball was dropped, pieces; N2 is the number of perforations that are effectively filled with fluid before and after the ball is dropped in the nth fracturing stage, pieces; N3 is the number of new effective perforations after the ball is dropped in the nth fracturing stage, pieces; Combining formulas (7) to (9), we can obtain N2= [AQ1 2 / ( P perf ·Q3 3 / Q4 3 +P2-P3) ] 0.5 (10) N1=[AQ1 2 / (P perf ·Q3 3 / Q4 3 +P1-P3) ] 0.5 -[AQ1 2 / (P perf ·Q3 3 / Q4 3 +P2-P3) ] 0.5 (11) The efficiency η of plugging perforations by temporary plugging balls in the nth fracturing stage n is the ratio of the total number of temporary plugging balls to the number of plugged holes, that is: η n =[N1 / (N1 +N2) ]×100% (12) Substituting formula (10) and (11) into formula (12), we can obtain the calculation method of plugging efficiency: η n =1-[(P perf ·Q3 3 / Q4 3 +P1-P3) / (P perf ·Q3 3 / Q4 3 +P2-P3) ] 0.5 ×100% (13)。 2. The post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing according to claim 1, characterized in that: The following formula is used to calculate the friction resistance P along the perforation path: well-perf : P well-perf = P(t p =0)- P(t p1 ) (1) Among them, P(t p1 ) is the time when the friction resistance along the perforation disappears t p1 The corresponding pressure, P(t p =0) is the initial pressure corresponding to when the pump is stopped.

3. The post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing according to claim 2, characterized in that: The friction coefficient α along the perforation is calculated using the following formula: α= P well-perf / Q 2 (2) Among them, Q is the instantaneous displacement before the pump stops.

4. The post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing according to claim 3, characterized in that: The following formula is used to calculate the friction coefficient gradient λ along the perforation of the nth fracturing stage in the horizontal well: n : l n =a n / H n (3) Where n is the horizontal well fracturing stage number, 1≤n≤k; k is the total number of fracturing stages; α n is the friction coefficient along the perforation of the nth fracturing stage; H n is the depth measured in the middle of the nth fracturing stage, in m; Based on the along-perforation friction coefficient gradient λ n Determine the minimum value of the friction coefficient gradient along the perforation min : l min =min(λ1,…,λ n ,…l k ) (4).

5. The post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing according to claim 4, characterized in that: The perforation friction coefficient ζ at the instant of pump stop in the nth fracturing stage is calculated using the following formula: n : g n =a n -H n l min (5) Wherein, based on the perforation friction coefficient ζ n Calculate the perforation friction P at the instant when the pump is stopped in the nth fracturing stage perf-n : P perf-n =ζ n Q n 2 (6) Among them, Q n It is the instantaneous displacement before pumping stops in the nth fracturing stage.

6. The post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing according to claim 2, characterized in that: According to the pressure P(t p ) and pump stop time t p Data, obtain the pressure difference derivative curve; Determine the time t at which the friction along the perforation disappears on the pressure difference derivative curve p1 And record the corresponding pressure P(t p1 ).

7. An electronic device, characterized in that: The electronic device comprises: A memory storing executable instructions; A processor, wherein the processor runs the executable instructions in the memory to implement the post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing as described in any one of claims 1 to 6.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the post-fracturing evaluation method for evaluating the plugging effect of temporary plugging balls in horizontal well fracturing is implemented as described in any one of claims 1-6.

Images