Control method and device for shot hole temporary plugging construction

Abstract

The invention provides a shot hole temporary plugging construction control method and device.The method comprises the steps that fracturing fluid displacement and target steering pressure of a target perforation section before temporary plugging are obtained; a shot hole temporary plugging ball number determination model is called, and the number of target temporary plugging balls is obtained through calculation; according to the displacement of the fracturing fluid after temporary plugging and the number of the target temporary plugging balls, theoretical steering pressure is obtained through calculation; under the condition that the theoretical steering pressure is not higher than the target steering pressure, the displacement of the fracturing fluid after temporary plugging is adjusted till the theoretical steering pressure is higher than the target steering pressure; according to the number of the target temporary plugging balls and the displacement of the target fracturing fluid after temporary plugging, temporary plugging construction of fracturing is conducted; and determining whether the temporary plugging construction is effective or not according to the comparison between the difference between the bottom hole pressure after the temporary plugging construction and the bottom hole pressure before the temporary plugging construction and the target steering pressure. According to the scheme, the number of the shot hole temporary plugging balls and the displacement of the fracturing fluid after temporary plugging can be accurately determined, and therefore the technical effect that fracturing construction can meet preset requirements is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil extraction, and in particular to a control method and device for temporary plugging of blastholes. Background Art

[0002] As a commonly used mining technology, horizontal well segmented fracturing technology can effectively improve the development and mining of unconventional oil and gas. At present, the length of the horizontal section of a horizontal well generally ranges from 500m to 5000m. Due to the limitation of this length range, it is necessary to adopt the process of horizontal well segmentation and cluster fracturing to achieve efficient fracture network construction.

[0003] However, due to the differences in lithology during the drilling of horizontal wells into the reservoir, the brittleness index in the reservoir will be different (for example, factors such as Young's modulus, Poisson's ratio, and natural fractures will lead to different brittleness indexes). Furthermore, due to geological and tectonic effects, the geomechanical parameters (for example, maximum horizontal principal stress, minimum horizontal principal stress, vertical stress, etc.) are quite different. These factors lead to different fracture initiation pressures between clusters within the segment. Through the results of on-site fracture microseismic monitoring, it can be found that uneven fracture initiation is common during the staged fracturing of horizontal wells, and even some perforations cannot be fractured. In order to further improve the fracturing effect of horizontal wells, a fracturing process of temporary plugging of blastholes is proposed, that is, during the fracturing process, degradable temporary plugging balls are used to plug the blastholes that have been opened, thereby forcing the bottom hole pressure to increase the efficiency of opening the perforation fractures in the segment. Specifically, the added temporary plugging balls can be naturally degraded under the formation temperature and pressure. After degradation, the blocked blastholes are opened, realizing the efficient construction of the horizontal well fracture network.

[0004] However, there is no effective solution yet on how to accurately determine the number of temporary plugging balls in the blasthole and the displacement of the fracturing fluid after temporary plugging so as to efficiently determine the effect of the temporary plugging construction. Summary of the invention

[0005] The purpose of the present application is to provide a control method and device for temporary plugging construction of blastholes, which can accurately determine the number of temporary plugging balls in blastholes and the displacement of fracturing fluid after temporary plugging, so that the fracturing construction can meet the preset requirements.

[0006] The present application provides a control method and device for temporary plugging of blastholes, which is implemented as follows:

[0007] A control method for temporary plugging of blastholes, the method comprising:

[0008] Obtain the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section;

[0009] Retrieve the pre-established model for determining the number of temporary plugging balls for blastholes;

[0010] The number of temporary plugging balls is calculated as the target number of temporary plugging balls through the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section, and the model for determining the number of temporary plugging balls in the blasthole;

[0011] The theoretical steering pressure is calculated according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls;

[0012] determining whether the theoretical steering pressure is higher than the target steering pressure, and if the theoretical steering pressure is not higher than the target steering pressure, adjusting the displacement of the fracturing fluid after temporary plugging until the calculated theoretical steering pressure is higher than the target steering pressure, and using the displacement of the fracturing fluid after temporary plugging corresponding to the calculated theoretical steering pressure being higher than the target steering pressure as the target displacement of the fracturing fluid after temporary plugging;

[0013] According to the determined target number of temporary plugging balls and target fracturing fluid discharge volume after temporary plugging, temporary plugging construction of fracturing is carried out;

[0014] Obtaining the bottom hole pressure at a preset first time point before temporary plugging construction and the bottom hole pressure at a second time point after temporary plugging construction;

[0015] Whether the temporary plugging construction is effective is determined based on the comparison between the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction and the target steering pressure.

[0016] In one embodiment, the model for determining the number of temporary plugging balls in the blasthole is expressed as:

[0017]

[0018] Among them, n is the number of perforations in the target perforation section, e is the natural base, N is the number of temporary plugging balls, and f n is the temporary blocking coefficient, f Q is the displacement coefficient, Q1 is the displacement of the fracturing fluid before temporary plugging, Q2 is the displacement of the fracturing fluid after temporary plugging, c1 is the shape coefficient of the perforation hole, c2 is the shape coefficient of the temporary plugging hole, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, α is the sand ratio, P de is the target steering pressure, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

[0019] In one embodiment, the theoretical steering pressure is calculated according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls, including:

[0020] The theoretical steering pressure is calculated according to the following formula:

[0021]

[0022] in, is the theoretical turning pressure, Q2 is the displacement of fracturing fluid after temporary plugging, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, α is the sand ratio, c1 is the perforation hole shape coefficient, c2 is the temporary plugging hole shape coefficient, Q1 is the fracturing fluid displacement before temporary plugging, f Q is the displacement coefficient, N represents the number of temporary plugging balls, n is the number of perforations in the target perforation section, and f n is the temporary plugging coefficient, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

[0023] In one embodiment, determining whether the temporary plugging construction is effective according to the comparison between the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction and the target steering pressure includes:

[0024] When the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction is greater than or equal to the target steering pressure, the temporary plugging construction is determined to be effective;

[0025] When the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction is less than the target steering pressure, determining that the temporary plugging construction is invalid;

[0026] When it is determined that the temporary plugging construction is ineffective, the fracturing fluid discharge volume after temporary plugging is adjusted, and the target number of temporary plugging balls and the target fracturing fluid discharge volume after temporary plugging are re-determined until the temporary plugging construction is determined to be effective.

[0027] In one embodiment, when the theoretical steering pressure is not higher than the target steering pressure, adjusting the displacement of the fracturing fluid after temporary plugging includes:

[0028] Adjust the fracturing fluid discharge volume after temporary plugging by 10% step.

[0029] In one embodiment, obtaining the bottom hole pressure at a preset first time point before temporary plugging construction and the bottom hole pressure at a second time point after temporary plugging construction includes:

[0030] The bottom hole pressure at the preset first time point before temporary plugging construction is calculated according to the following formula:

[0031]

[0032] Among them, PBHP1 Q is the bottom hole pressure at the first time point preset before temporary plugging construction. pupm1 is the displacement of the fracturing fluid at the first time point preset before temporary plugging construction, m1 is the density coefficient of the sand-carrying fluid, m2 is the flow coefficient of the sand-carrying fluid, k is the viscosity coefficient of the fracturing fluid, d tub is the inner diameter of the fracturing string, h td is the vertical depth of the fracturing section, h md is the depth measurement of the fracturing section, a is the flow index of the fracturing fluid, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, and α1 is the sand ratio at the first time point preset before temporary plugging construction.

[0033] The bottom hole pressure at the second time point after temporary plugging is calculated according to the following formula:

[0034]

[0035] Among them, P BHP2 is the bottom hole pressure at the second time point after temporary plugging construction, Q pupm2 is the fracturing fluid displacement at the second time point after the temporary plugging construction, and α2 is the sand ratio at the second time point after the temporary plugging construction.

[0036] In one embodiment, the density coefficient of the sand-carrying liquid and the flow coefficient of the sand-carrying liquid are determined as follows:

[0037] The proppant used in the fracturing process is used as the target proppant;

[0038] Obtaining the type and mesh size of the target proppant;

[0039] Determining the volume density and apparent density of the target proppant according to the type and mesh size of the target proppant;

[0040] Obtain target sand ratio and target displacement;

[0041] According to the volume density of the target proppant and the apparent density of the target proppant, the density of the sand-carrying fluid under the target sand ratio is calculated:

[0042] The friction gradient is calculated through a friction test under the target displacement and the target sand ratio;

[0043] According to the relationship between the friction gradient and the density coefficient of the sand-carrying liquid, the flow coefficient of the sand-carrying liquid and the density of the sand-carrying liquid under the target sand ratio, the density coefficient of the sand-carrying liquid and the flow coefficient of the sand-carrying liquid are obtained by fitting.

[0044] In one embodiment, the density of the sand-carrying fluid at the target sand ratio is calculated according to the volume density of the target proppant and the apparent density of the target proppant, comprising:

[0045] The density of the sand-carrying liquid under the target sand ratio is calculated according to the following formula:

[0046]

[0047] Among them, ρ ls-α is the density of the sand-carrying fluid;

[0048] The friction gradient is calculated according to the following formula:

[0049] G ls-α =P / L

[0050] Among them, G ls-α is the friction gradient, P is the friction resistance, and L is the length of the target pipeline;

[0051] The relationship between the friction gradient and the density coefficient of the sand-carrying liquid, the flow coefficient of the sand-carrying liquid and the density of the sand-carrying liquid under the target sand ratio is expressed as follows:

[0052]

[0053] A control device for temporary plugging of blastholes, comprising:

[0054] An acquisition module is used to acquire the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section;

[0055] A calling module is used to call a pre-established model for determining the number of temporary plugging balls for blastholes;

[0056] The first calculation module is used to calculate the number of temporary plugging balls as the target number of temporary plugging balls through the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section, and the model for determining the number of temporary plugging balls in the blasthole;

[0057] A second calculation module is used to calculate the theoretical steering pressure according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls;

[0058] an adjustment module, for determining whether the theoretical steering pressure is higher than the target steering pressure, and when the theoretical steering pressure is not higher than the target steering pressure, adjusting the displacement of the fracturing fluid after temporary plugging until the calculated theoretical steering pressure is higher than the target steering pressure, and using the displacement of the fracturing fluid after temporary plugging corresponding to the calculated theoretical steering pressure being higher than the target steering pressure as the target displacement of the fracturing fluid after temporary plugging;

[0059] A construction module, used to perform temporary plugging construction of fracturing according to the determined target number of temporary plugging balls and target fracturing fluid discharge volume after temporary plugging;

[0060] The third acquisition module is used to obtain the bottom hole pressure at a preset first time point before the temporary plugging construction and the bottom hole pressure at a second time point after the temporary plugging construction;

[0061] The determination module is used to determine whether the temporary plugging construction is effective based on the comparison between the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction and the target steering pressure.

[0062] An electronic device comprises a processor and a memory for storing instructions executable by the processor, wherein the steps of the above method are implemented when the processor executes the instructions.

[0063] A computer-readable storage medium stores a computer program / instruction, which implements the steps of the above method when executed by a processor.

[0064] The control method and device for temporary plugging construction of blastholes provided in the present application determine the model through the number of temporary plugging balls of blastholes, calculate the target number of temporary plugging balls, calculate the theoretical steering pressure according to the number of temporary plugging balls and the obtained displacement of fracturing fluid after temporary plugging, and adjust the displacement of fracturing fluid after temporary plugging when the theoretical steering pressure is not higher than the target steering pressure until the theoretical steering pressure is higher than the target steering pressure, and the corresponding target displacement of fracturing fluid after temporary plugging can be obtained; determine whether the temporary plugging construction is effective according to the comparison between the difference between the bottom hole pressure after temporary plugging construction and the bottom hole pressure before temporary plugging construction and the target steering pressure. The above scheme can realize the accurate determination of the number of temporary plugging balls of blastholes and the displacement of fracturing fluid after temporary plugging, so that the fracturing construction can meet the preset requirements, and realize the effective evaluation of the temporary plugging pressure-boosting effect after blasthole temporary plugging and fracturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0066] Figure 1 This is a method flow chart of an embodiment of a control method for temporary plugging construction of blastholes provided by the present application;

[0067] Figure 2 It is a fracturing construction curve change diagram provided by this application;

[0068] Figure 3 It is a hardware structure block diagram of an electronic device for a control method of temporary blasthole plugging construction provided by the present application;

[0069] Figure 4 It is a schematic diagram of the module structure of an embodiment of a control device for temporary plugging construction of blastholes provided in the present application. DETAILED DESCRIPTION

[0070] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0071] In view of the problem that the temporary plugging parameters cannot be accurately determined in the existing fracturing process of temporary plugging of blastholes, and the temporary plugging and pressure-boosting effect after temporary plugging and fracturing of blastholes cannot be effectively determined, a control method for temporary plugging construction of blastholes is provided in an embodiment of the present application. Although the present application provides method operation steps or device structures as shown in the following embodiments or drawings, more or fewer operation steps or module units may be included in the method or device based on routine or no creative labor. In the steps or structures that do not logically have necessary causal relationships, the execution order of these steps or the module structure of the device is not limited to the execution order or module structure described in the embodiments of the present application and shown in the drawings. When the method or module structure is applied in an actual device or terminal product, it can be connected according to the method or module structure shown in the embodiment or drawings for sequential execution or parallel execution (for example, a parallel processor or a multi-threaded processing environment, or even a distributed processing environment).

[0072] Specifically, Figure 1 As shown, the control method for temporary plugging of blastholes mentioned above may include the following steps:

[0073] S101: Obtaining the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section.

[0074] The target steering pressure can be obtained based on the geomechanical analysis of a single well, and the displacement of the fracturing fluid before temporary plugging can be obtained based on the initial fracturing pumping procedure.

[0075] S102: Retrieve a pre-established model for determining the number of temporary plugging balls for blastholes.

[0076] In order to determine the number of temporary blocking balls, a model for determining the number of temporary blocking balls for a blasthole is provided in this example. The model for determining the number of temporary blocking balls for a blasthole can be pre-established and stored in a server. When it is determined that the number of temporary blocking balls needs to be calculated, it can be obtained from the server and the output number of temporary blocking balls can be calculated based on the input relevant parameters.

[0077] Specifically, the model for determining the number of temporary blocking balls in the blasthole can be expressed as:

[0078]

[0079] Among them, n is the number of perforations in the target perforation section, e is the natural base, N is the number of temporary plugging balls, and f n is the temporary blocking coefficient, f Q is the displacement coefficient, Q1 is the displacement of the fracturing fluid before temporary plugging, Q2 is the displacement of the fracturing fluid after temporary plugging, c1 is the shape coefficient of the perforation hole, c2 is the shape coefficient of the temporary plugging hole, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, α is the sand ratio, P de is the target steering pressure, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

[0080] The above-mentioned perforation hole shape coefficient c1, opening rate η and hole expansion rate ζ can be obtained from indoor experiments of blasthole perforation or underground TV field experiments; the temporary plugging hole shape coefficient c2 can be obtained from indoor experiments of sand-carrying fluid blasthole erosion; the temporary plugging coefficient f n and displacement factor f Q It can be obtained by the indoor experiment of temporary plugging of blastholes. However, it is worth noting that the above-mentioned method of determining these parameters is only an exemplary description and does not constitute an improper limitation on this application. In actual implementation, other appropriate methods can be selected according to the needs and on-site conditions, and this application does not limit this.

[0081] S103: Calculate the number of temporary plugging balls as the target number of temporary plugging balls through the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section, and the model for determining the number of temporary plugging balls in the blasthole.

[0082] Furthermore, considering that when determining the number of temporary plugging balls based on the above-mentioned blasthole temporary plugging ball number determination model, there is a case where the calculation result is a non-integer, that is, the calculation result is a decimal, such as 12.3. In this case, rounding up can be performed and the result of rounding up can be used as the determined number of temporary plugging balls, for example, 12.3 is taken as 13.

[0083] S104: Calculate and obtain a theoretical steering pressure according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls.

[0084] Considering that the determination of the displacement of the fracturing fluid after temporary plugging is a process of continuous adjustment and determination, in order to determine the appropriate displacement of the fracturing fluid after temporary plugging, it is necessary to determine the theoretical steering pressure. Based on this, a calculation model of the theoretical steering pressure is provided in this example, and the calculation model of the theoretical steering pressure can be expressed as:

[0085]

[0086] in, is the theoretical turning pressure, Q2 is the displacement of fracturing fluid after temporary plugging, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, α is the sand ratio, c1 is the perforation hole shape coefficient, c2 is the temporary plugging hole shape coefficient, Q1 is the fracturing fluid displacement before temporary plugging, f Q is the displacement coefficient, N represents the number of temporary plugging balls, n is the number of perforations in the target perforation section, and f n is the temporary plugging coefficient, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

[0087] S105: Determine whether the theoretical steering pressure is higher than the target steering pressure. If the theoretical steering pressure is not higher than the target steering pressure, adjust the displacement of the fracturing fluid after temporary plugging until the calculated theoretical steering pressure is higher than the target steering pressure, and use the displacement of the fracturing fluid after temporary plugging corresponding to the calculated theoretical steering pressure being higher than the target steering pressure as the target displacement of the fracturing fluid after temporary plugging.

[0088] That is, when the theoretical steering pressure is calculated, the theoretical steering pressure can be compared with the target steering pressure. It is necessary to ensure that the theoretical steering pressure is higher than the target steering pressure. If this requirement cannot be met, the displacement of the fracturing fluid after temporary plugging needs to be adjusted. When adjusting the displacement of the fracturing fluid after temporary plugging, it can be gradually adjusted according to a preset ratio value (i.e., adjustment gradient). For example, the preset ratio value can be 5%, 10%, 15%, etc. The specific ratio value can be determined according to the actual construction conditions or the demand for precision. Through this operation, a displacement of the fracturing fluid after temporary plugging can be finally determined as the target fracturing fluid displacement after temporary plugging.

[0089] S106: Perform temporary plugging construction of fracturing according to the determined target number of temporary plugging balls and target fracturing fluid discharge volume after temporary plugging.

[0090] S107: Obtaining the bottom hole pressure at a preset first time point before the temporary plugging construction and the bottom hole pressure at a second time point after the temporary plugging construction.

[0091] In order to accurately determine the bottom hole pressure, a bottom hole pressure calculation model is provided in this example. The bottom hole pressure calculation model can be expressed as:

[0092]

[0093] Among them, P BHP is the bottom hole pressure, in MPa, Q pupm is the displacement of fracturing fluid, in m 3 / min, m1 is the density coefficient of the sand-carrying fluid, m2 is the flow coefficient of the sand-carrying fluid, k is the consistency coefficient of the fracturing fluid, the unit is Pa.s, d tub is the inner diameter of the fracturing string, in m, h td is the vertical depth of the fracturing section, in m, h md is the depth of the fracturing section, in m, a is the flow index of the fracturing fluid, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, and α is the sand ratio.

[0094] Specifically, the temporary plugging pressure can be calibrated by the temporary plugging pressure curve, and the bottom hole pressure before temporary plugging and the bottom hole pressure after temporary plugging are calibrated by the temporary plugging time. The pressure before temporary plugging is the pressure before temporary plugging, and the pressure after temporary plugging is the pressure after temporary plugging. For the bottom hole pressure at the first preset time point before temporary plugging construction and the bottom hole pressure at the second time point after temporary plugging construction, the difference is the fracturing fluid displacement and sand ratio, because the fracturing fluid displacement and sand ratio change before and after temporary plugging. Based on this, the above bottom hole pressure calculation model can be converted to:

[0095] The bottom hole pressure at the preset first time point before temporary plugging construction is calculated according to the following formula:

[0096]

[0097] Among them, P BHP1 Q is the bottom hole pressure at the first time point preset before temporary plugging construction. pupm1 is the displacement of the fracturing fluid at the first time point preset before temporary plugging construction, m1 is the density coefficient of the sand-carrying fluid, m2 is the flow coefficient of the sand-carrying fluid, k is the viscosity coefficient of the fracturing fluid, d tub is the inner diameter of the fracturing string, h td is the vertical depth of the fracturing section, h md is the depth measurement of the fracturing section, a is the flow index of the fracturing fluid, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, and α1 is the sand ratio at the first time point preset before temporary plugging construction.

[0098] The bottom hole pressure at the second time point after temporary plugging is calculated according to the following formula:

[0099]

[0100] Among them, P BHP2 is the bottom hole pressure at the second time point after temporary plugging construction, Q pupm2 is the fracturing fluid displacement at the second time point after the temporary plugging construction, and α2 is the sand ratio at the second time point after the temporary plugging construction.

[0101] In one embodiment, the above-mentioned preset first time point can be five minutes, ten minutes, fifteen minutes, etc. before the temporary blocking construction. Similarly, the second time point after the temporary blocking construction can be five minutes, ten minutes, fifteen minutes, etc. after the temporary blocking construction. The specific time point can be determined according to actual conditions, and the embodiments of this specification do not limit this.

[0102] S108: Determine whether the temporary plugging construction is effective based on a comparison between a difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction and the target steering pressure.

[0103] In one embodiment, when the difference between the bottom hole pressure at the second time point after the temporary plugging construction and the bottom hole pressure at the first time point preset before the temporary plugging construction is greater than or equal to the target steering pressure, it means that the pressure generated by the temporary plugging construction can meet the demand, and therefore the temporary plugging construction is determined to be effective; when the difference between the bottom hole pressure at the second time point after the temporary plugging construction and the bottom hole pressure at the first time point preset before the temporary plugging construction is less than the target steering pressure, it means that the pressure generated by the temporary plugging construction does not meet the demand, and therefore the temporary plugging construction is determined to be invalid. Accordingly, when it is determined that the temporary plugging construction is invalid, it is necessary to adjust the displacement of the fracturing fluid after the temporary plugging, and determine the model based on the number of temporary plugging balls in the blasthole and the theoretical steering pressure calculation model, re-determine the target number of temporary plugging balls and the target displacement of the fracturing fluid after the temporary plugging, and recalculate the bottom hole pressure at the first time point preset before the temporary plugging construction and the bottom hole pressure at the second time point after the temporary plugging construction through the bottom hole pressure calculation model, so as to evaluate whether the temporary plugging construction is effective, until it is determined that the temporary plugging construction is effective.

[0104] Furthermore, in the above-mentioned model for calculating bottom hole pressure, two parameters are involved: density coefficient m1 of the sand-carrying fluid and flow coefficient m2 of the sand-carrying fluid. The density coefficient m1 of the sand-carrying fluid and the flow coefficient m2 of the sand-carrying fluid are related to the proppant type and the diameter of the proppant particles, and need to be measured in the laboratory or on-site. In this example, a measurement method is proposed for the measurement of the density coefficient m1 of the sand-carrying fluid and the flow coefficient m2 of the sand-carrying fluid, which may include:

[0105] S1: For a certain type of proppant (e.g. ceramsite, quartz sand, etc.), obtain the mesh size of the proppant (e.g. 20 / 40, 40 / 70, etc.) and the fracturing fluid system, then determine the bulk density and apparent density of the proppant, and design the target sand ratio (e.g. 5%, 10%, 15%);

[0106] S2: Based on the bulk density and apparent density of the proppant, the density of the sand-carrying fluid at the target sand ratio is calculated according to the following formula: ls-α ;

[0107]

[0108] Among them, ρ ls-α is the density of the sand-carrying fluid;

[0109] S3: Design the target pipeline diameter and target displacement, and measure the friction resistance under the target displacement. Through the friction resistance test under the target displacement and target sand ratio, the friction resistance gradient is calculated according to the following formula:

[0110] G ls-α =P / L

[0111] Among them, G ls-α is the friction gradient, P is the friction resistance, and L is the length of the target pipeline;

[0112] S4: According to the following relationship between the friction gradient and the density coefficient of the sand-carrying liquid, the flow coefficient of the sand-carrying liquid and the density of the sand-carrying liquid under the target sand ratio, the density coefficient of the sand-carrying liquid m1 and the flow coefficient of the sand-carrying liquid m2 are obtained by fitting:

[0113]

[0114] The above method is described below in conjunction with a specific embodiment. However, it should be noted that this specific embodiment is only for better illustrating the present application and does not constitute an improper limitation on the present application.

[0115] In this case, considering the problems in the existing fracturing process for temporary plugging of blastholes, such as the inability to accurately determine the number of temporary plugging balls and the inability to accurately determine the displacement of fracturing fluid after temporary plugging, which leads to the inability to accurately evaluate the temporary plugging effect of temporary plugging design parameters, a blasthole temporary plugging parameter design and temporary plugging effect evaluation model is proposed. Through this model, a more accurate design can be made by combining the perforation density, the number of temporary plugging balls under the perforation thickness, the displacement of fracturing fluid after temporary plugging, etc. At the same time, the temporary plugging and pressure-boosting effect after hydraulic fracturing can also be accurately evaluated based on parameters such as fracturing fluid displacement, proppant density, and wellhead pump pressure, thereby guiding the efficient exploration and exploitation of horizontal wells in unconventional reservoirs such as shale gas and coalbed methane.

[0116] Specifically, in this example, a design model for the number of temporary plugging balls for blastholes is provided, which is expressed as:

[0117]

[0118] Among them, N is the number of temporary plugging balls, n is the number of perforations in the target perforation section, e is the natural base number, and f is the number of holes in the target perforation section. n is the temporary blocking coefficient, f Q is the displacement coefficient, Q1 is the displacement of the fracturing fluid before temporary plugging, in m 3 / min, Q2 is the displacement of fracturing fluid after temporary plugging, unit is m 3 / min, c1 is the perforation hole shape coefficient, the value is between 0 and 1, c2 is the temporary plugging hole shape coefficient, the value is between 0 and 1, ρ l is the density of fracturing fluid, in kg / m 3 , ρ sz is the apparent density of the proppant, in kg / m 3 , ρ sv is the proppant density, in kg / m 3 , α is the sand ratio, P de is the target steering pressure in MPa, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

[0119] Furthermore, in order to determine the target fracturing fluid displacement after temporary plugging, it is necessary to calculate the theoretical steering pressure. Specifically, the theoretical steering pressure can be first calculated based on the fracturing fluid displacement after temporary plugging and the target number of temporary plugging balls; then, it is determined whether the theoretical steering pressure is higher than the target steering pressure. When the theoretical steering pressure is not higher than the target steering pressure, the fracturing fluid displacement after temporary plugging is adjusted until the calculated theoretical steering pressure is higher than the target steering pressure, and the fracturing fluid displacement after temporary plugging corresponding to the calculated theoretical steering pressure being higher than the target steering pressure is used as the target fracturing fluid displacement after temporary plugging.

[0120] In order to calculate the theoretical diversion pressure, a fracturing fluid displacement design model after temporary plugging of the blasthole is provided in this example, which is expressed as:

[0121]

[0122] in, is the theoretical turning pressure, Q2 is the displacement of fracturing fluid after temporary plugging, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, α is the sand ratio, c1 is the perforation hole shape coefficient, c2 is the temporary plugging hole shape coefficient, Q1 is the fracturing fluid displacement before temporary plugging, f Qis the displacement coefficient, N represents the number of temporary plugging balls, n is the number of perforations in the target perforation section, and f n is the temporary plugging coefficient, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

[0123] The above-mentioned perforation hole shape coefficient c1, opening rate η and hole expansion rate ζ can be obtained from indoor experiments of blasthole perforation or from underground TV field experiments. The temporary plugging hole shape coefficient c2 can be obtained through indoor experiments of sand-carrying fluid blasthole erosion. It is the temporary plugging coefficient f n and displacement factor f Q , which can be obtained through indoor experiments on temporary plugging of blastholes.

[0124] Based on the design model of fracturing fluid displacement after temporary plugging of blastholes, the target steering pressure P can be obtained according to the geomechanical analysis of a single well. de , according to the initial fracturing pumping program, the fracturing fluid displacement Q1 before temporary plugging is obtained, and the fracturing fluid displacement Q2 after temporary plugging is designed. Then, the number of temporary plugging balls is calculated using the design model for the number of temporary plugging balls in the blasthole. When calculating the number of temporary plugging balls, if the calculated number of temporary plugging balls N is a decimal (i.e., non-integer), the integer is rounded up as the calculated temporary plugging ball format. Then, the above-mentioned design model for the displacement of fracturing fluid after temporary plugging of the blasthole is used to calculate if The number of temporary plugging balls N and the displacement of fracturing fluid Q2 after temporary plugging are reasonably designed; if Then adjust the fracturing fluid discharge volume after temporary plugging by 10% step until the calculated value is The number of temporary plugging balls and the displacement of fracturing fluid after temporary plugging are obtained.

[0125] After determining the number of temporary plugging balls and the displacement of fracturing fluid after temporary plugging, the temporary plugging and pressure-raising effect after temporary plugging and fracturing of the blasthole can be evaluated. In order to achieve the evaluation of the temporary plugging and pressure-raising effect, a model for calculating the bottom hole pressure is given in this example. Through this model, the bottom hole pressure at the preset first time point before the temporary plugging construction and the bottom hole pressure at the second time point after the temporary plugging construction can be calculated. The model for calculating the bottom hole pressure can be expressed as:

[0126]

[0127] Among them, P BHP is the bottom hole pressure, in MPa, Q pupm is the displacement of fracturing fluid, in m 3 / min, m1 is the density coefficient of the sand-carrying fluid, m2 is the flow coefficient of the sand-carrying fluid, k is the consistency coefficient of the fracturing fluid, the unit is Pa.s, d tub is the inner diameter of the fracturing string, in m, h td is the vertical depth of the fracturing section, in m, h mdis the depth of the fracturing section, in m, a is the flow index of the fracturing fluid, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, and α is the sand ratio.

[0128] When implementing, the parameters such as fracturing fluid displacement and sand ratio can be obtained according to the fracturing construction curve. Then, the bottom hole pressure curve is calculated by the above-mentioned bottom hole pressure calculation model. Based on the bottom hole pressure curve, the bottom hole pressure P 10 minutes before temporary plugging is read respectively. BHP-pre , Bottom hole pressure P 10 minutes after temporary plugging BHP-post , if P BHP-post -P BHP-pre >P de , then it is determined that temporary blocking is effective. If P BHP-post -P BHP-pre ≤P de , it is determined that the temporary plugging is invalid, and it is necessary to redetermine the number of temporary plugging balls and the displacement of fracturing fluid after temporary plugging.

[0129] Furthermore, in the above-mentioned model for calculating bottom hole pressure, two parameters are involved: density coefficient m1 of the sand-carrying fluid and flow coefficient m2 of the sand-carrying fluid. The density coefficient m1 of the sand-carrying fluid and the flow coefficient m2 of the sand-carrying fluid are related to the proppant type and the diameter of the proppant particles, and need to be measured in the laboratory or on-site. In this example, a measurement method is proposed for the measurement of the density coefficient m1 of the sand-carrying fluid and the flow coefficient m2 of the sand-carrying fluid, which may include:

[0130] S1: For a certain type of proppant (e.g. ceramsite, quartz sand, etc.), obtain the mesh size of the proppant (e.g. 20 / 40, 40 / 70, etc.) and the fracturing fluid system, then determine the bulk density and apparent density of the proppant, and design the target sand ratio (e.g. 5%, 10%, 15%);

[0131] S2: Based on the bulk density and apparent density of the proppant, the density of the sand-carrying fluid at the target sand ratio is calculated according to the following formula: ls-α ;

[0132]

[0133] Among them, ρ ls-α is the density of the sand-carrying fluid;

[0134] S3: Design the target pipeline diameter and target displacement, and measure the friction resistance under the target displacement. Through the friction resistance test under the target displacement and target sand ratio, the friction resistance gradient is calculated according to the following formula:

[0135] G ls-α =P / L

[0136] Among them, G ls-α is the friction gradient, P is the friction resistance, and L is the length of the target pipeline;

[0137] S4: According to the following relationship between the friction gradient and the density coefficient of the sand-carrying liquid, the flow coefficient of the sand-carrying liquid and the density of the sand-carrying liquid under the target sand ratio, the density coefficient of the sand-carrying liquid m1 and the flow coefficient of the sand-carrying liquid m2 are obtained by fitting:

[0138]

[0139] The above fracturing results are explained by taking a specific example. Specifically, assuming that the pressure data are: the measured depth of the fracturing section is 5146m, the vertical depth of the fracturing section is 3944m, the inner diameter of the fracturing string is 0.1397m, and the density of the fracturing fluid is 1030kg / m 3 , proppant body density is 1490kg / m 3 , the apparent density of the proppant is 2625kg / m 3 After fracturing based on these fracturing parameters, the obtained displacement, sand concentration, wellhead pressure and bottom hole pressure change curves over time can be shown as follows: Figure 2 As shown, the bottom hole pressure before and after each fracturing can be obtained from Figure 2 The change curve can be read to determine the effect of temporary plugging and fracturing.

[0140] In the above example, the temporary plugging parameters are designed more accurately by combining the perforation density, the number of temporary plugging balls under the perforation thickness, the fracturing fluid displacement after temporary plugging, etc. At the same time, the temporary plugging and pressure-boosting effect after hydraulic fracturing can also be accurately evaluated based on parameters such as fracturing fluid displacement, proppant density, and wellhead pump pressure, thereby guiding the efficient exploration and exploitation of horizontal wells in unconventional reservoirs such as shale gas and coalbed methane.

[0141] The method embodiments provided in the above embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Taking running on an electronic device as an example, Figure 3 This is a hardware structure block diagram of an electronic device for a control method of temporary blasthole plugging construction provided by this application. Figure 3 As shown, the electronic device 10 may include one or more (only one is shown in the figure) processors 02 (the processor 02 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA), a memory 04 for storing data, and a transmission module 06 for communication functions. It can be understood by those skilled in the art that Figure 3 The structure shown is only for illustration and does not limit the structure of the above electronic device. Figure 3 More or fewer components as shown, or with Figure 3 Different configurations are shown.

[0142] The memory 04 can be used to store software programs and modules of application software, such as program instructions / modules corresponding to the control method for temporary plugging of blastholes in the embodiment of the present application. The processor 02 executes various functional applications and data processing by running the software programs and modules stored in the memory 04, that is, the control method for temporary plugging of blastholes of the above-mentioned application is realized. The memory 04 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 04 may further include a memory remotely arranged relative to the processor 02, and these remote memories may be connected to the electronic device 10 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0143] The transmission module 06 is used to receive or send data via a network. The specific example of the above network may include a wireless network provided by a communication provider of the electronic device 10. In one example, the transmission module 06 includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission module 06 can be a radio frequency (Radio Frequency, RF) module, which is used to communicate with the Internet wirelessly.

[0144] At the software level, the control device for temporary plugging of blastholes can be Figure 4 As shown, including:

[0145] An acquisition module 401 is used to acquire the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section;

[0146] The retrieving module 402 is used to retrieve a pre-established model for determining the number of temporary plugging balls for blastholes;

[0147] The first calculation module 403 is used to calculate the number of temporary plugging balls as the target number of temporary plugging balls through the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section, and the model for determining the number of temporary plugging balls in the blasthole;

[0148] A second calculation module 404 is used to calculate a theoretical steering pressure according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls;

[0149] An adjustment module 405 is used to determine whether the theoretical steering pressure is higher than the target steering pressure, and if the theoretical steering pressure is not higher than the target steering pressure, adjust the displacement of the fracturing fluid after temporary plugging until the calculated theoretical steering pressure is higher than the target steering pressure, and use the displacement of the fracturing fluid after temporary plugging corresponding to the calculated theoretical steering pressure being higher than the target steering pressure as the target displacement of the fracturing fluid after temporary plugging;

[0150] Construction module 406, for performing temporary plugging construction of fracturing according to the determined target number of temporary plugging balls and target fracturing fluid displacement after temporary plugging;

[0151] The third acquisition module 407 is used to acquire the bottom hole pressure at a preset first time point before the temporary plugging construction and the bottom hole pressure at a second time point after the temporary plugging construction;

[0152] The determination module 408 is used to determine whether the temporary plugging construction is effective based on the comparison between the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction and the target steering pressure.

[0153] In one embodiment, the above-mentioned model for determining the number of temporary plugging balls in the blasthole can be expressed as:

[0154]

[0155] Among them, n is the number of perforations in the target perforation section, e is the natural base, N is the number of temporary plugging balls, and f n is the temporary blocking coefficient, f Q is the displacement coefficient, Q1 is the displacement of the fracturing fluid before temporary plugging, Q2 is the displacement of the fracturing fluid after temporary plugging, c1 is the shape coefficient of the perforation hole, c2 is the shape coefficient of the temporary plugging hole, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, α is the sand ratio, P de is the target steering pressure, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

[0156] In one embodiment, the second calculation module 404 may be used to calculate the theoretical steering pressure according to the following formula:

[0157]

[0158] in, is the theoretical turning pressure, Q2 is the displacement of fracturing fluid after temporary plugging, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ svis the proppant density, α is the sand ratio, c1 is the perforation hole shape coefficient, c2 is the temporary plugging hole shape coefficient, Q1 is the fracturing fluid displacement before temporary plugging, f Q is the displacement coefficient, N represents the number of temporary plugging balls, n is the number of perforations in the target perforation section, and f n is the temporary plugging coefficient, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

[0159] In one embodiment, the above-mentioned determination module 408 can be specifically used to determine that the temporary plugging construction is effective when the difference between the bottom hole pressure at the second time point after the temporary plugging construction and the bottom hole pressure at the first time point preset before the temporary plugging construction is greater than or equal to the target steering pressure; determine that the temporary plugging construction is invalid when the difference between the bottom hole pressure at the second time point after the temporary plugging construction and the bottom hole pressure at the first time point preset before the temporary plugging construction is less than the target steering pressure; when it is determined that the temporary plugging construction is invalid, adjust the fracturing fluid displacement after temporary plugging, and re-determine the target number of temporary plugging balls and the target fracturing fluid displacement after temporary plugging until it is determined that the temporary plugging construction is effective.

[0160] In one embodiment, when the theoretical steering pressure is not higher than the target steering pressure, adjusting the displacement of the fracturing fluid after temporary plugging may include: adjusting the displacement of the fracturing fluid after temporary plugging in steps of 10%.

[0161] In one embodiment, the third acquisition module 407 can be specifically used to calculate the bottom hole pressure at a preset first time point before temporary plugging construction according to the following formula:

[0162]

[0163] Among them, P BHP1 Q is the bottom hole pressure at the first time point preset before temporary plugging construction. pupm1 is the displacement of the fracturing fluid at the first time point preset before temporary plugging construction, m1 is the density coefficient of the sand-carrying fluid, m2 is the flow coefficient of the sand-carrying fluid, k is the viscosity coefficient of the fracturing fluid, d tub is the inner diameter of the fracturing string, h td is the vertical depth of the fracturing section, h md is the depth measurement of the fracturing section, a is the flow index of the fracturing fluid, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, and α1 is the sand ratio at the first time point preset before temporary plugging construction.

[0164] The bottom hole pressure at the second time point after temporary plugging is calculated according to the following formula:

[0165]

[0166] Among them, PBHP2 is the bottom hole pressure at the second time point after temporary plugging construction, Q pupm2 is the fracturing fluid displacement at the second time point after the temporary plugging construction, and α2 is the sand ratio at the second time point after the temporary plugging construction.

[0167] In one embodiment, the density coefficient of the sand-carrying fluid and the flow coefficient of the sand-carrying fluid can be determined as follows: the proppant used in the fracturing process is used as the target proppant; the type and mesh size of the target proppant are obtained; the volume density of the target proppant and the apparent density of the target proppant are determined according to the type and mesh size of the target proppant; the target sand ratio and the target displacement are obtained; the density of the sand-carrying fluid under the target sand ratio is calculated according to the volume density of the target proppant and the apparent density of the target proppant: the friction gradient is calculated through the friction experiment under the target displacement and the target sand ratio; the density coefficient of the sand-carrying fluid and the flow coefficient of the sand-carrying fluid are fitted according to the relationship between the friction gradient and the density coefficient of the sand-carrying fluid, the flow coefficient of the sand-carrying fluid and the density of the sand-carrying fluid under the target sand ratio.

[0168] In one embodiment, according to the volume density of the target proppant and the apparent density of the target proppant, calculating the density of the sand-carrying fluid at the target sand ratio may include:

[0169] The density of the sand-carrying liquid under the target sand ratio is calculated according to the following formula:

[0170]

[0171] Among them, ρ ls-α is the density of the sand-carrying fluid;

[0172] The friction gradient can be calculated according to the following formula:

[0173] G ls-α =P / L

[0174] Among them, G ls-α is the friction gradient, P is the friction resistance, and L is the length of the target pipeline;

[0175] The relationship between the friction gradient and the density coefficient of the sand-carrying liquid, the flow coefficient of the sand-carrying liquid and the density of the sand-carrying liquid under the target sand ratio can be expressed as:

[0176]

[0177] The embodiment of the present application also provides a specific implementation of an electronic device capable of implementing all the steps in the control method for temporary plugging of blastholes in the above embodiment. The electronic device specifically includes the following contents: a processor, a memory, a communications interface, and a bus; wherein the processor, the memory, and the communications interface communicate with each other through the bus; the processor is used to call a computer program in the memory, and when the processor executes the computer program, all the steps in the control method for temporary plugging of blastholes in the above embodiment are implemented. For example, when the processor executes the computer program, the following steps are implemented:

[0178] Step 1: Obtain the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section;

[0179] Step 2: Retrieve the pre-established model for determining the number of temporary plugging balls for blastholes;

[0180] Step 3: Calculate the number of temporary plugging balls as the target number of temporary plugging balls through the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section, and the model for determining the number of temporary plugging balls in the blasthole;

[0181] Step 4: Calculate the theoretical steering pressure according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls;

[0182] Step 5: Determine whether the theoretical steering pressure is higher than the target steering pressure. If the theoretical steering pressure is not higher than the target steering pressure, adjust the displacement of the fracturing fluid after temporary plugging until the calculated theoretical steering pressure is higher than the target steering pressure, and use the displacement of the fracturing fluid after temporary plugging corresponding to the calculated theoretical steering pressure being higher than the target steering pressure as the target displacement of the fracturing fluid after temporary plugging;

[0183] Step 6: Perform temporary plugging construction of fracturing according to the determined target number of temporary plugging balls and target fracturing fluid displacement after temporary plugging;

[0184] Step 7: Obtaining the bottom hole pressure at a preset first time point before temporary plugging construction and the bottom hole pressure at a second time point after temporary plugging construction;

[0185] Step 8: Determine whether the temporary plugging construction is effective based on the comparison between the difference between the bottom hole pressure at the second time point after the temporary plugging construction and the bottom hole pressure at the preset first time point before the temporary plugging construction and the target steering pressure.

[0186] The embodiments of the present application also provide a computer-readable storage medium capable of implementing all the steps in the control method for temporary plugging of blastholes in the above embodiments. The computer-readable storage medium stores a computer program. When the computer program is executed by a processor, all the steps in the control method for temporary plugging of blastholes in the above embodiments are implemented. For example, when the processor executes the computer program, the following steps are implemented:

[0187] Step 1: Obtain the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section;

[0188] Step 2: Retrieve the pre-established model for determining the number of temporary plugging balls for blastholes;

[0189] Step 3: Calculate the number of temporary plugging balls as the target number of temporary plugging balls through the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section, and the model for determining the number of temporary plugging balls in the blasthole;

[0190] Step 4: Calculate the theoretical steering pressure according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls;

[0191] Step 5: Determine whether the theoretical steering pressure is higher than the target steering pressure. If the theoretical steering pressure is not higher than the target steering pressure, adjust the displacement of the fracturing fluid after temporary plugging until the calculated theoretical steering pressure is higher than the target steering pressure, and use the displacement of the fracturing fluid after temporary plugging corresponding to the calculated theoretical steering pressure being higher than the target steering pressure as the target displacement of the fracturing fluid after temporary plugging;

[0192] Step 6: Perform temporary plugging construction of fracturing according to the determined target number of temporary plugging balls and target fracturing fluid displacement after temporary plugging;

[0193] Step 7: Obtaining the bottom hole pressure at a preset first time point before temporary plugging construction and the bottom hole pressure at a second time point after temporary plugging construction;

[0194] Step 8: Determine whether the temporary plugging construction is effective based on the comparison between the difference between the bottom hole pressure at the second time point after the temporary plugging construction and the bottom hole pressure at the preset first time point before the temporary plugging construction and the target steering pressure.

[0195] From the above description, it can be seen that the embodiment of the present application determines the model through the number of temporary plugging balls in the blasthole, calculates the target number of temporary plugging balls, calculates the theoretical steering pressure according to the number of temporary plugging balls and the obtained displacement of the fracturing fluid after temporary plugging, and when the theoretical steering pressure is not higher than the target steering pressure, adjusts the displacement of the fracturing fluid after temporary plugging until the theoretical steering pressure is higher than the target steering pressure, and the corresponding target displacement of the fracturing fluid after temporary plugging can be obtained; according to the comparison between the difference between the bottom hole pressure after the temporary plugging construction and the bottom hole pressure before the temporary plugging construction and the target steering pressure, it is determined whether the temporary plugging construction is effective. The above scheme can realize the accurate determination of the number of temporary plugging balls in the blasthole and the displacement of the fracturing fluid after temporary plugging, so that the fracturing construction can meet the preset requirements, and realize the effective evaluation of the temporary plugging boosting effect after the blasthole temporary plugging fracturing.

[0196] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the hardware + program embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0197] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0198] Although the present application provides method operation steps as described in the embodiments or flowcharts, more or fewer operation steps may be included based on conventional or non-creative labor. The order of steps listed in the embodiments is only one way of executing the order of many steps and does not represent the only execution order. When the actual device or client product is executed, it can be executed in the order of the method shown in the embodiments or the drawings or in parallel (for example, in a parallel processor or multi-threaded processing environment).

[0199] Although the present specification embodiment provides the method operation steps as described in the embodiment or flow chart, more or less operation steps may be included based on conventional or non-creative means. The order of steps listed in the embodiment is only one way in the order of execution of many steps, and does not represent a unique execution order. When the device or terminal product in practice is executed, it can be executed in sequence or in parallel (such as a parallel processor or a multi-threaded processing environment, or even a distributed data processing environment) according to the method shown in the embodiment or the accompanying drawings. The term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, product or equipment including a series of elements not only includes those elements, but also includes other elements not clearly listed, or also includes elements inherent to such process, method, product or equipment. In the absence of more restrictions, it is not excluded that there are other identical or equivalent elements in the process, method, product or equipment including the elements.

[0200] For the convenience of description, the above devices are described in various modules according to their functions. Of course, when implementing the embodiments of this specification, the functions of each module can be implemented in the same or more software and / or hardware, or the module implementing the same function can be implemented by a combination of multiple sub-modules or sub-units. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0201] Those skilled in the art also know that, in addition to implementing the controller in a purely computer-readable program code, the controller can be made to implement the same function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, such a controller can be considered as a hardware component, and the devices for implementing various functions included therein can also be considered as structures within the hardware component. Or even, the devices for implementing various functions can be considered as both software modules for implementing the method and structures within the hardware component.

[0202] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0203] Those skilled in the art will appreciate that the embodiments of this specification may be provided as methods, systems or computer program products. Therefore, the embodiments of this specification may take the form of complete hardware embodiments, complete software embodiments or embodiments combining software and hardware. Moreover, the embodiments of this specification may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0204] The present specification embodiments may be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present specification embodiments may also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules may be located in local and remote computer storage media, including storage devices.

[0205] Each embodiment in this specification is described in a progressive manner, and the same and similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. In the description of this specification, the description of the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of this specification. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, in the absence of contradiction, a person skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0206] The above is only an example of the embodiment of the present specification and is not intended to limit the embodiment of the present specification. For those skilled in the art, the embodiment of the present specification may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiment of the present specification shall be included in the scope of the claims of the embodiment of the present specification.

Claims

1. A control method for temporary plugging of blastholes, characterized in that: The method comprises: Obtain the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section; Retrieve the pre-established model for determining the number of temporary plugging balls for blastholes; The number of temporary plugging balls is calculated as the target number of temporary plugging balls through the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section, and the model for determining the number of temporary plugging balls in the blasthole; The theoretical steering pressure is calculated according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls; determining whether the theoretical steering pressure is higher than the target steering pressure, and if the theoretical steering pressure is not higher than the target steering pressure, adjusting the displacement of the fracturing fluid after temporary plugging until the calculated theoretical steering pressure is higher than the target steering pressure, and using the displacement of the fracturing fluid after temporary plugging corresponding to the calculated theoretical steering pressure being higher than the target steering pressure as the target displacement of the fracturing fluid after temporary plugging; According to the determined target number of temporary plugging balls and target fracturing fluid discharge volume after temporary plugging, temporary plugging construction of fracturing is carried out; Obtaining the bottom hole pressure at a preset first time point before temporary plugging construction and the bottom hole pressure at a second time point after temporary plugging construction; Whether the temporary plugging construction is effective is determined based on the comparison between the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction and the target steering pressure.

2. The method according to claim 1, characterized in that The model for determining the number of temporary plugging balls in blastholes is expressed as: Among them, n is the number of perforations in the target perforation section, e is the natural base, N is the number of temporary plugging balls, and f n is the temporary blocking coefficient, f Q is the displacement coefficient, Q1 is the displacement of the fracturing fluid before temporary plugging, Q2 is the displacement of the fracturing fluid after temporary plugging, c1 is the shape coefficient of the perforation hole, c2 is the shape coefficient of the temporary plugging hole, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, α is the sand ratio, P de is the target steering pressure, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

3. The method according to claim 1, characterized in that The theoretical steering pressure is calculated according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls, including: The theoretical steering pressure is calculated according to the following formula: in, is the theoretical turning pressure, Q2 is the displacement of fracturing fluid after temporary plugging, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant density, α is the sand ratio, c1 is the perforation hole shape coefficient, c2 is the temporary plugging hole shape coefficient, Q1 is the fracturing fluid displacement before temporary plugging, f Q is the displacement coefficient, N represents the number of temporary plugging balls, n is the number of perforations in the target perforation section, and f n is the temporary plugging coefficient, η is the opening ratio, ζ is the hole expansion ratio, and d is the hole diameter.

4. The method according to claim 1, characterized in that: Determining whether the temporary plugging construction is effective according to the comparison between the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction and the target steering pressure, includes: When the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction is greater than or equal to the target steering pressure, the temporary plugging construction is determined to be effective; When the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction is less than the target steering pressure, determining that the temporary plugging construction is invalid; When it is determined that the temporary plugging construction is ineffective, the fracturing fluid discharge volume after temporary plugging is adjusted, and the target number of temporary plugging balls and the target fracturing fluid discharge volume after temporary plugging are re-determined until the temporary plugging construction is determined to be effective.

5. The method according to claim 1, characterized in that When the theoretical steering pressure is not higher than the target steering pressure, the displacement of the fracturing fluid after temporary plugging is adjusted, including: Adjust the fracturing fluid discharge volume after temporary plugging by 10% step.

6. The method according to claim 1, characterized in that Obtaining the bottom hole pressure at a preset first time point before temporary plugging construction and the bottom hole pressure at a second time point after temporary plugging construction, including: The bottom hole pressure at the preset first time point before temporary plugging construction is calculated according to the following formula: Among them, P BHP1 Q is the bottom hole pressure at the first time point preset before temporary plugging construction. pupm1 is the displacement of the fracturing fluid at the first time point preset before temporary plugging construction, m1 is the density coefficient of the sand-carrying fluid, m2 is the flow coefficient of the sand-carrying fluid, k is the viscosity coefficient of the fracturing fluid, d tub is the inner diameter of the fracturing string, h td is the vertical depth of the fracturing section, h md is the depth measurement of the fracturing section, a is the flow index of the fracturing fluid, ρ l is the density of fracturing fluid, ρ sz is the apparent density of the proppant, ρ sv is the proppant body density, α1 is the sand ratio at the first time point preset before temporary plugging construction; The bottom hole pressure at the second time point after temporary plugging is calculated according to the following formula: Among them, P BHP2 is the bottom hole pressure at the second time point after temporary plugging construction, Q pupm2 is the fracturing fluid displacement at the second time point after the temporary plugging construction, and α2 is the sand ratio at the second time point after the temporary plugging construction.

7. The method according to claim 6, characterized in that Determine the density coefficient and flow coefficient of the sand-carrying fluid as follows: The proppant used in the fracturing process is used as the target proppant; Obtaining the type and mesh size of the target proppant; Determining the volume density and apparent density of the target proppant according to the type and mesh size of the target proppant; Obtain target sand ratio and target displacement; According to the volume density of the target proppant and the apparent density of the target proppant, the density of the sand-carrying fluid under the target sand ratio is calculated: The friction gradient is calculated through a friction test under the target displacement and the target sand ratio; According to the relationship between the friction gradient and the density coefficient of the sand-carrying liquid, the flow coefficient of the sand-carrying liquid and the density of the sand-carrying liquid under the target sand ratio, the density coefficient of the sand-carrying liquid and the flow coefficient of the sand-carrying liquid are obtained by fitting.

8. The method according to claim 7, characterized in that The density of the sand-carrying liquid at the target sand ratio is calculated according to the volume density of the target proppant and the apparent density of the target proppant, including: The density of the sand-carrying liquid under the target sand ratio is calculated according to the following formula: Among them, ρ ls-α is the density of the sand-carrying fluid; The friction gradient is calculated according to the following formula: G ls-α =P / L Among them, G ls-α is the friction gradient, P is the friction resistance, and L is the length of the target pipeline; The relationship between the friction gradient and the density coefficient of the sand-carrying liquid, the flow coefficient of the sand-carrying liquid and the density of the sand-carrying liquid under the target sand ratio is expressed as follows:

9. A control device for temporary plugging of blastholes, characterized in that: include: An acquisition module is used to acquire the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section; A calling module is used to call a pre-established model for determining the number of temporary plugging balls for blastholes; The first calculation module is used to calculate the number of temporary plugging balls as the target number of temporary plugging balls through the fracturing fluid displacement before temporary plugging, the fracturing fluid displacement after temporary plugging, the fracturing fluid density, the proppant apparent density, the sand ratio and the target steering pressure of the target perforation section, and the model for determining the number of temporary plugging balls in the blasthole; A second calculation module is used to calculate the theoretical steering pressure according to the displacement of the fracturing fluid after temporary plugging and the target number of temporary plugging balls; an adjustment module, for determining whether the theoretical steering pressure is higher than the target steering pressure, and when the theoretical steering pressure is not higher than the target steering pressure, adjusting the displacement of the fracturing fluid after temporary plugging until the calculated theoretical steering pressure is higher than the target steering pressure, and using the displacement of the fracturing fluid after temporary plugging corresponding to the calculated theoretical steering pressure being higher than the target steering pressure as the target displacement of the fracturing fluid after temporary plugging; A construction module, used to perform temporary plugging construction of fracturing according to the determined target number of temporary plugging balls and target fracturing fluid discharge volume after temporary plugging; The third acquisition module is used to obtain the bottom hole pressure at a preset first time point before the temporary plugging construction and the bottom hole pressure at a second time point after the temporary plugging construction; The determination module is used to determine whether the temporary plugging construction is effective based on the comparison between the difference between the bottom hole pressure at a second time point after the temporary plugging construction and the bottom hole pressure at a preset first time point before the temporary plugging construction and the target steering pressure.

10. An electronic device comprising a processor and a memory for storing instructions executable by the processor, characterized in that: When the processor executes the instructions, the steps of the method according to any one of claims 1 to 8 are implemented.

11. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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