Temporary plugging ball and system and method for determining setting of temporary plugging ball

Abstract

The embodiment of the invention provides a temporary plugging ball and a system and method for determining setting of the temporary plugging ball, and belongs to the field of temporary plugging fracturing. The temporary blocking ball comprises a shell; the pressure sensor is arranged on the outer surface of the shell and used for measuring the pressure around the temporary blocking ball; the data processing and pulse signal transmitter is arranged in the shell, connected with the pressure sensor and used for judging whether the temporary plugging ball is set on a perforation hole or not based on the pressure value of the pressure sensor and transmitting a preset pulse signal when the temporary plugging ball is set on the perforation hole; and the energy supply device is arranged in the shell, is connected with the data processing and pulse signal transmitter, and is used for providing energy for the data processing and pulse signal transmitter and the pressure sensor. The method is used for solving the problems that at present, whether a temporary plugging ball is set or not cannot be judged, and the number of plugged perforation holes cannot be calculated.

Description

Technical Field

[0001] This invention relates to the field of temporary plugging fracturing, and more specifically to a temporary plugging ball, a system and method for determining the setting of the temporary plugging ball. Background Technology

[0002] Temporary plugging fracturing technology is now widely used, and the plugging ball used to seal perforation holes is a key component of this technology. Generally, these plugging balls are required to have good pressure resistance and dissolution properties. Currently, plugging balls have the following main characteristics: First, they are made of biodegradable (dissolvable) materials with a certain pressure resistance, such as polyglycolic acid and polylactic acid; second, the shape of the plugging ball is spherical, generally made into solid spheres, hollow spheres, or woven knots using different weaving methods, resulting in certain structural differences; third, for the outer shell of the knotted plugging ball, there are generally two types: one is a rigid biodegradable shell, which can be broken during movement to release the knots inside; the second is a biodegradable flexible shell, which generally covers the outside of the knots, facilitating ball transport and plugging; fourth, the weaving material of the knotted plugging ball is made of various materials, such as resin, glycerin, and fibers (PVA, PLA, and PET); fifth, each plugging ball has certain differences in size, temperature resistance, pressure resistance, and pumping parameters.

[0003] Overall, current plugging balls are functionally similar, differing only in material and usage parameters. For temporary plugging fracturing, knowing how many plugging balls are set and how many perforations are blocked in each instance is crucial, serving as a measure of plugging success and effectiveness. However, current plugging balls cannot determine whether they are set, thus hindering the calculation of the number of blocked perforations. This is a shortcoming of existing technology. Summary of the Invention

[0004] The purpose of this invention is to provide a temporary plugging ball, a system and method for determining whether the temporary plugging ball is set, in order to solve the current problems of not being able to determine whether the temporary plugging ball is set and not being able to calculate the number of plugging perforations.

[0005] To achieve the above objectives, in a first aspect, embodiments of the present invention provide a temporary clogging ball, the temporary clogging ball comprising a shell, and further comprising: a pressure sensor disposed on the outer surface of the shell for measuring the pressure around the temporary clogging ball; a data processing and pulse signal transmitter disposed inside the shell and connected to the pressure sensor for determining whether the temporary clogging ball is seated on the perforation orifice based on the pressure value of the pressure sensor, and for transmitting a pre-set pulse signal when the temporary clogging ball is seated on the perforation orifice; and an energy supply device disposed inside the shell and connected to the data processing and pulse signal transmitter for providing energy to the data processing and pulse signal transmitter and the pressure sensor.

[0006] Optionally, the temporary blocking ball further includes an inner shell, which is disposed inside the outer shell and outside the data processing and pulse signal transmitter and the energy supply device.

[0007] Optionally, the outer shell is a biodegradable flexible outer shell, and the inner shell is a biodegradable inner shell.

[0008] Optionally, the temporary plugging ball further includes a biodegradable woven filler that fills the space between the outer shell and the inner shell of the temporary plugging ball, as well as the interior of the inner shell.

[0009] Optionally, the number of pressure sensors is two or more.

[0010] Optionally, the pressure sensors are arranged on multiple large circles of the temporary blocking ball, the multiple large circles intersecting at the same diameter, and a preset number of pressure sensors are evenly arranged on each of the large circles.

[0011] Optionally, the included angle between the planes of adjacent large circles is 40°-50°.

[0012] Optionally, determining whether the temporary plugging ball is seated on the perforation orifice based on the pressure value of the pressure sensor includes: counting the pressure values ​​of all pressure sensors of the temporary plugging ball; recording the largest pressure value as the first pressure value; recording the pressure values ​​whose difference from the first pressure value is greater than a preset value as the second pressure value; calculating the ratio of the number of second pressure values ​​to the number of all pressure values; and if the ratio is not less than a preset threshold, determining that the temporary plugging ball is seated on the perforation orifice.

[0013] Optionally, the preset pulse signal includes pulse signals of different ranges, the pulse signals of the same range correspond to the temporary blocking ball of the same diameter, and the temporary blocking ball of the same diameter corresponds to at least one range of pulse signals, wherein the range includes the signal intensity and frequency.

[0014] Secondly, embodiments of the present invention provide a system for determining the setting of a temporary plugging ball, the system comprising: a temporary plugging ball as described in any of the preceding claims of the present invention; a data acquisition device disposed at the wellhead near the casing head for receiving pulse signals from the temporary plugging ball; and a processor connected to the data acquisition device for counting the number of temporary plugging balls set based on the pulse signals.

[0015] Optionally, the processor is further configured to determine the diameter of the temporary plug ball of each seated block based on the range of the received pulse signals.

[0016] Thirdly, embodiments of the present invention provide a method for determining the setting of a temporary choke ball as described in any of the above claims, the method comprising: receiving a pulse signal from the temporary choke ball; and counting the number of pulse signals, wherein the number of pulse signals is the number of temporary choke balls set.

[0017] Optionally, the method further includes: determining the diameter of the temporary plugging ball of each seated block based on the range of each of the received pulse signals.

[0018] Through the above technical solution, the temporary blocking ball proposed in this invention is equipped with a pressure sensor and a data processing and pulse signal transmitter. The data processing and pulse signal transmitter can determine whether the temporary blocking ball has set on the perforation orifice by receiving pressure changes from the pressure sensor, and emits a pre-set pulse signal when the temporary blocking ball sets on the perforation orifice. When the operator receives the pulse signal emitted by the data processing and pulse signal transmitter, it can determine that the temporary blocking ball has successfully set. When multiple temporary blocking balls are deployed, the number of temporarily blocking balls set can be determined by the number of pulse signals received, and the number of temporarily blocking balls set also corresponds to the number of perforation orifices blocked.

[0019] After staff determine whether the plugging ball has set, they can use the results to guide the adjustment of the on-site plugging fracturing process parameters in real time, thereby improving the effectiveness of plugging fracturing.

[0020] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0022] Figure 1 This is a schematic diagram of a temporary blocking ball provided in an embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of the pressure sensor distribution of a temporary blocking ball provided in an embodiment of the present invention.

[0024] Figure 3 This is a partial structural schematic diagram of a system for determining the setting of a temporary plugging ball, provided by an embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures

[0026] 1. Pressure sensor 2. Housing

[0027] 3 Inner shell 4 Data processing and pulse signal transmitter

[0028] 5. Energy supply device; 6. Biodegradable woven filling.

[0029] 7 acquisition devices 8 processors

[0030] 9 cables 10 conductor wires Detailed Implementation

[0031] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0032] Figure 1 This is a schematic diagram of a temporary blocking ball provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the present invention provides a temporary clogging ball, the temporary clogging ball including a shell 2, the temporary clogging ball further including: a pressure sensor 1, disposed on the outer surface of the shell 2, for measuring the pressure around the temporary clogging ball; a data processing and pulse signal transmitter 4, disposed inside the shell 2 and connected to the pressure sensor 1, for determining whether the temporary clogging ball is seated on the perforation orifice based on the pressure value of the pressure sensor 1, and for transmitting a pre-set pulse signal when the temporary clogging ball is seated on the perforation orifice; and an energy supply device 5, disposed inside the shell 2 and connected to the data processing and pulse signal transmitter 4, for providing energy to the data processing and pulse signal transmitter 4 and the pressure sensor 1.

[0033] The energy supply device 5 can be a battery or a capacitor, and is connected to the data processing and pulse signal transmitter 4 via the conduction line 10. It is used to provide energy to the data processing and pulse signal transmitter 4 and the pressure sensor 1, to ensure the normal operation of the data processing and pulse signal transmitter 4 and the pressure sensor 1, and to ensure that the pulse signal can be transmitted to the wellhead and received.

[0034] It is understood that the temporary plugging ball can be designed with different diameters. In one embodiment of the present invention, the diameter is designed to be 13mm-30mm. In other embodiments of the present invention, the diameter can also be adjusted as needed. Regardless of the diameter, the material and internal structure of the temporary plugging ball are consistent.

[0035] During use, after the temporary plugging ball sets on the perforation hole, because part of the sensor is inside the perforation hole, its pressure value will be lower than the pressure value of the pressure sensor 1 exposed in the wellbore. The data processing and pulse signal transmitter 4 can determine whether the temporary plugging ball has set on the perforation hole based on the received pressure value. After the temporary plugging ball sets on the perforation hole, the data processing and pulse signal transmitter 4 emits a pre-set pulse signal. The operator can determine whether the temporary plugging ball has been successfully set based on the received pulse signal. The operator can also determine the number of temporary plugging balls set based on the number of received pulse signals. The number of temporarily plugging balls set is the number of perforation holes sealed. This solves the current problem of not being able to determine whether the temporary plugging ball has set and the inability to accurately calculate the number of perforation holes sealed during temporary plugging fracturing. It can effectively guide the real-time adjustment of temporary plugging fracturing process parameters and help improve the effect of temporary plugging fracturing.

[0036] Furthermore, the temporary blocking ball also includes an inner shell 3, which is disposed inside the outer shell 2 and outside the data processing and pulse signal transmitter 4 and the energy supply device 5.

[0037] The temporary blocking ball proposed in this invention is provided with an inner shell 3, and the data processing and pulse signal transmitter 4 and the energy supply device 5 are all located inside the inner shell 3, so as to provide better protection and support for the data processing and pulse signal transmitter 4 and the energy supply device 5.

[0038] Furthermore, the outer shell 2 is a biodegradable flexible outer shell, and the inner shell 3 is a biodegradable inner shell.

[0039] To achieve the degradation function of the temporary blocking ball, both the outer shell 2 and the inner shell 3 are made of biodegradable materials. In one embodiment of the invention, the energy supply device 5 and the data processing and pulse signal transmitter 4 are also made of biodegradable materials.

[0040] The outer shell 2 has good flexibility and can withstand a certain degree of deformation, which facilitates transportation and sealing of irregular perforations, improving the sealing effect. In one embodiment of the present invention, the outer shell 2 is made of biodegradable polyurethane elastomer composite material, polycarbonate, etc., and the biodegradable inner shell 3 is made of PGA, etc. Other materials can also be selected, provided that the production requirements of the outer shell 2 and the inner shell 3 can be met; the present invention is not limited thereto.

[0041] Furthermore, the temporary plugging ball also includes a biodegradable woven filler 6, which fills the space between the outer shell 2 and the inner shell 3 of the temporary plugging ball, as well as inside the inner shell 3.

[0042] Apart from electronic components, the interior of the temporary plugging ball is filled with biodegradable woven filler 6. Biodegradable woven filler 6 can be made of materials such as PGA to meet the requirements of pressure resistance and complete degradation of the temporary plugging ball.

[0043] Furthermore, the number of pressure sensors 1 is two or more.

[0044] Understandably, because the temporary plugging ball is spherical, if only one pressure sensor 1 is installed on a single ball, the pressure sensor 1 may not be positioned inside the perforation orifice after the ball is seated on it, leading to incorrect judgment. Therefore, two or more pressure sensors 1 should be installed to meet the requirements for pressure value judgment.

[0045] Furthermore, the pressure sensor 1 is arranged on multiple large circles of the temporary blocking ball, the multiple large circles intersect on the same diameter, and a preset number of pressure sensors 1 are evenly arranged on each of the large circles.

[0046] It should be noted that the large circle is the intersection of the plane passing through the center of the sphere and the sphere's surface, which is the outer shell 2 of the temporary plugging ball. The purpose of this arrangement is to make the pressure sensors 1 more evenly distributed on the outer shell 2 of the temporary plugging ball. In other embodiments of the present invention, other distribution methods may also be used, and the present invention is not limited thereto.

[0047] Furthermore, the included angle between the planes containing adjacent large circles is 40°-50°.

[0048] The angle between the planes where adjacent large circles are located should not be too large or too small, to avoid calculation errors caused by too few pressure sensors or excessive cost and power consumption caused by too many pressure sensors.

[0049] Figure 2 This is a schematic diagram showing the distribution of a pressure sensor 1 for a temporary blocking ball according to an embodiment of the present invention. Please refer to it. Figure 2In one embodiment of the present invention, 8 to 12 pressure sensors 1 are uniformly arranged on each large circle, and the included angle between the planes of adjacent large circles is 45°. A total of 32 to 48 pressure sensors 1 are arranged on one temporary plugging ball. The outer shell of the pressure sensor 1 is made of a biodegradable material, such as PGA or PLA, and is cylindrical with a diameter of 2 mm to 4 mm and a height of 2 mm to 4 mm. It is attached to the outer shell 2 of the temporary plugging ball by adhesive bonding. The operating temperature range of the pressure sensor 1 is 5℃ to 200℃, and the operating pressure range is 0.05 MPa to 180 MPa. The operating temperature range of the entire temporary plugging ball is 60℃ to 200℃, and the operating pressure range is 40 MPa to 70 MPa.

[0050] Furthermore, determining whether the temporary plugging ball is seated on the perforation orifice based on the pressure value of the pressure sensor 1 includes: counting the pressure values ​​of all pressure sensors 1 of the temporary plugging ball; recording the largest pressure value among the pressure values ​​as the first pressure value; recording the pressure values ​​whose difference from the first pressure value is greater than a preset value as the second pressure value; calculating the ratio of the number of second pressure values ​​to the number of all pressure values; and if the ratio is not less than a preset threshold, determining that the temporary plugging ball is seated on the perforation orifice.

[0051] It should be noted that for the same plugging ball, the pressure values ​​of multiple pressure sensors 1 exposed inside the wellbore are almost identical. Therefore, the difference between the pressure value of this portion of pressure sensors 1 and the first pressure value is extremely small. However, the pressure value of the pressure sensors 1 inside the perforation orifice will have a larger difference from the first pressure value. A threshold can be set according to the actual situation. When the ratio of the number of second pressure values ​​in a certain plugging ball to the total number of pressure values ​​exceeds this threshold, it is determined that the plugging ball is set on the perforation orifice. In one embodiment of the present invention, the threshold is set to 30%, that is, when not less than 30% of the pressure sensors 1 are set on the perforation orifice, it is considered that the plugging ball is set on the perforation orifice.

[0052] Furthermore, the pre-set pulse signal includes pulse signals of different ranges, the pulse signals of the same range correspond to the temporary blocking ball of the same diameter, and the temporary blocking ball of the same diameter corresponds to at least one range of pulse signals, wherein the range includes the signal intensity and frequency.

[0053] When designing temporary tamping balls, different pulse signals are set for different balls, such as pulse signals of different intensities and frequencies. The same pulse signal corresponds to a temporary tamping ball of the same diameter. Upon receiving a pulse signal, it's possible to distinguish which diameter of temporary tamping ball has successfully set, thus providing more precise guidance for temporary fracturing. However, temporary tamping balls of the same diameter need to be set with one or more pulse signal ranges because, in some cases, multiple temporary tamping balls of the same diameter may need to be deployed simultaneously. If temporary tamping balls of the same diameter are set with the same pulse signal, signal interference may occur. By deploying temporary tamping balls of the same diameter but with different pulse signals, signal interference can be avoided, ensuring uninterrupted reception.

[0054] Figure 3 This is a partial structural diagram of a system for determining the setting of a temporary plugging ball according to an embodiment of the present invention, as shown below. Figure 3 As shown, an embodiment of the present invention provides a system for determining the setting of a temporary plugging ball. The system includes: a temporary plugging ball as described in any of the above claims of the present invention; a data acquisition device 7, disposed at the wellhead near the casing head, for receiving pulse signals from the temporary plugging ball; and a processor 8, connected to the data acquisition device 7, for counting the number of temporary plugging balls set based on the pulse signals.

[0055] In one embodiment of the present invention, the processor 8 is a computer and supporting software, the acquisition device 7 is a wellhead data acquisition sensor, and the processor 8 and the acquisition device 7 are connected by a cable 9 to record and display the number of temporary plugging balls set.

[0056] Furthermore, the processor 8 is also configured to determine the diameter of the temporary plugging ball of each seated block based on the range of the received pulse signals.

[0057] The processor 8 stores the pulse signal range and diameter information of various types of temporary blocking balls. When the processor 8 receives a pulse signal, it can distinguish the corresponding diameter based on the range of each pulse signal.

[0058] This invention also provides a method for determining the setting of a temporary choke ball as described in any of the above claims, the method comprising: receiving a pulse signal from the temporary choke ball; and counting the number of pulse signals, wherein the number of pulse signals is the number of temporary choke balls set.

[0059] Furthermore, the method also includes: determining the diameter of the temporary plugging ball of each seated block based on the range of each of the received pulse signals.

[0060] Example 1: Using temporary plugging balls to guide the process parameters of temporary plugging fracturing at the construction site.

[0061] S101: Install the acquisition device, i.e., the wellhead data acquisition sensor, at the wellhead near the casing head and connect it to the processor via a cable.

[0062] S102: Select temporary plugging balls of different diameters according to the fracturing design and determine the number to be used.

[0063] S103: Select temporary plugging balls with different pulse signal ranges to ensure that they can be received by the wellhead data acquisition sensor within the operating depth range.

[0064] S104: Place the selected temporary blocking ball into the temporary blocking ball dispenser.

[0065] S105: Debug the processor to ensure it is in normal working order.

[0066] S106: Deploy temporary plugging balls. After the balls are in place, i.e., after the construction pressure has risen to a stable level, the number and diameter of the temporary plugging balls set are determined by the data provided by the processor to guide the adjustment of subsequent temporary plugging fracturing process parameters, such as how many temporary plugging balls to deploy, the diameter and density of the temporary plugging balls, the displacement of the temporary plugging balls, and the viscosity of the liquid.

[0067] At the construction site, repeat steps S102 to S106 above until the temporary plugging fracturing is completed.

[0068] In addition to the temporary plugging and degradation functions of conventional temporary plugging balls, the temporary plugging ball proposed in this invention can also solve the problems of not being able to determine whether the temporary plugging ball is set and the number of perforation holes to be plugged in the current temporary plugging fracturing process. It can effectively guide the real-time adjustment of temporary plugging fracturing process parameters and help improve the temporary plugging fracturing effect.

[0069] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0070] Furthermore, the terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different parts.

[0071] It should also be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention depending on the specific circumstances. When a specific device is described as being located between a first device and a second device, an intermediary device may or may not be present between the specific device and the first or second device.

[0072] All terms used in this invention have the same meaning as understood by one of ordinary skill in the art to which this invention pertains, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and not as idealized or highly formalized, unless expressly defined herein.

[0073] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0074] The acquisition, transmission, storage, use, and processing of data in this application all comply with the relevant provisions of national laws and regulations.

[0075] It should be noted that in the embodiments of this application, certain software, components, models and other existing solutions in the industry may be mentioned. These should be regarded as exemplary and are only intended to illustrate the feasibility of implementing the technical solution of this application. However, it does not mean that the applicant has used or necessarily used the solution.

[0076] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A temporary clogging ball, the temporary clogging ball comprising a shell, characterized in that, The temporary blocking ball also includes: A pressure sensor, disposed on the outer surface of the housing, is used to measure the pressure around the temporary plugging ball; A data processing and pulse signal transmitter, disposed inside the housing and connected to the pressure sensor, is used to determine whether the temporary plugging ball is set on the perforation orifice based on the pressure value of the pressure sensor, and to emit a pre-set pulse signal when the temporary plugging ball is set on the perforation orifice; and An energy supply device is disposed inside the housing and connected to the data processing and pulse signal transmitter, for providing energy to the data processing and pulse signal transmitter and the pressure sensor.

2. The temporary blocking ball according to claim 1, characterized in that, The temporary blocking ball also includes an inner shell, which is disposed inside the outer shell and outside the data processing and pulse signal transmitter and the energy supply device.

3. The temporary blocking ball according to claim 2, characterized in that, The outer shell is a biodegradable flexible outer shell, and the inner shell is a biodegradable inner shell.

4. The temporary blocking ball according to claim 2, characterized in that, The temporary plugging ball also includes a biodegradable woven filler that fills the space between the outer shell and the inner shell of the temporary plugging ball, as well as the interior of the inner shell.

5. The temporary blocking ball according to claim 1, characterized in that, The number of pressure sensors is two or more.

6. The temporary blocking ball according to claim 5, characterized in that, The pressure sensors are arranged on multiple large circles of the temporary blocking ball, and the multiple large circles intersect on the same diameter. A preset number of pressure sensors are evenly arranged on each of the large circles.

7. The temporary blocking ball according to claim 6, characterized in that, The included angle between the planes of adjacent great circles is 40°-50°.

8. The temporary blocking ball according to any one of claims 5-7, characterized in that, Determining whether the temporary plugging ball is set on the perforation orifice based on the pressure value of the pressure sensor includes: Statistically analyze the pressure values ​​of all pressure sensors on the temporary clogging ball; The largest pressure value among the pressure values ​​is recorded as the first pressure value; The pressure value whose difference from the first pressure value is greater than a preset value is recorded as the second pressure value; Calculate the ratio of the number of the second pressure values ​​to the total number of all said pressure values; and If the ratio is not less than a preset threshold, it is determined that the temporary plugging ball is seated on the perforation hole.

9. The temporary blocking ball according to claim 1, characterized in that, The preset pulse signals include pulse signals of different ranges. Pulse signals of the same range correspond to temporary plugging balls of the same diameter, and temporary plugging balls of the same diameter correspond to at least one range of pulse signals. The range includes both the signal strength and frequency.

10. A system for determining the setting of a temporary plugging ball, characterized in that, The system includes: The temporary blocking ball as described in any one of claims 1-9; The acquisition device, located near the casing head at the wellhead, is used to receive the pulse signal from the temporary plugging ball; and The processor, connected to the acquisition device, is used to count the number of temporary blocking balls set based on the pulse signal.

11. The system according to claim 10, characterized in that, The processor is also configured to determine the diameter of the temporary plug ball of each seat based on the range of the received pulse signals.

12. A method for determining the setting of a temporary choke ball as described in any one of claims 1-9, characterized in that, The method includes: Receive the pulse signal of the temporarily blocked ball; and The number of pulse signals is counted, and the number of pulse signals is the number of temporary blocking balls set.

13. The method according to claim 12, characterized in that, The method further includes: The diameter of the temporary plugging ball of each seat is determined based on the range of each of the received pulse signals.

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