A method for testing a production fluid profile of a horizontal well

Abstract

The present application relates to a kind of horizontal well liquid production profile testing method, belong to oil and gas field testing technical field.The specific steps are as follows: step one, preparation before testing;Step two, segmented setting is carried out;Step three, data acquisition;Step four, recovery logging instrument;Step five, interpretation liquid production profile.The present application uses the logging instrument with soluble metal and perforating gun, soluble bridge plug is combined, solves the technical problem of long horizontal section horizontal well fracturing effect evaluation, shortens the long horizontal section liquid production profile test time of each section, improves test success rate, test efficiency.

Description

Technical Field

[0001] This invention relates to a method for testing the production profile of horizontal wells, belonging to the field of oil and gas field testing technology. Background Technology

[0002] Horizontal well production profile testing technology can identify the production and flowback patterns of each fractured section, understand the downhole production dynamics, provide a basis for production optimization, and play a role in increasing oil and gas well production and reducing development costs.

[0003] Horizontal well production profile testing technology primarily utilizes coiled tubing or a crawler to deliver testing instruments equipped with multiple sensors to measure parameters such as pressure, temperature, and flow rate in different sections. However, both coiled tubing and crawlers present significant challenges in instrument delivery, including high testing costs. Furthermore, as the horizontal section exceeds a certain length, the coiled tubing's delivery capacity decreases, and the crawler may experience slippage or insufficient traction. In complex well conditions or with residual debris, the crawler risks becoming stuck downhole, significantly increasing the probability of test failure. The process is complex and costly. Currently, there is a lack of low-cost, high-efficiency production profile testing methods for multi-stage fracturing horizontal wells.

[0004] A correct understanding of the geometry and extension of fracturing fractures is crucial for evaluating fracturing effectiveness, improving the accuracy of fracturing design, optimizing development plans, and ultimately increasing single-well productivity. Common fracture monitoring methods include well test analysis, well temperature logging, radioactive tracer logging, and microseismic methods. Radioactive tracer logging requires the use of radioactive tracer particles, which poses a risk of radioactive pollution to humans and the environment, and is inconvenient to use. Microseismic methods require the deployment of numerous geophones on the surface or downhole, resulting in complex construction processes, long cycles, and high costs. Furthermore, this method itself has inherent uncertainties and lacks necessary comparative verification methods, and the interpretation of data errors requires further investigation. Pre- and post-fracturing well temperature and pressure recovery data can be used for well test analysis to calculate fracture parameters in each segment. Well test analysis and well temperature logging technologies are mature and inexpensive, but conventional temperature and pressure testing processes are not suitable for multi-stage fracturing in horizontal wells. Currently, there are no feasible and convenient well temperature logging and post-fracturing data testing methods for multi-stage fracturing in horizontal wells, making it impossible to obtain pressure recovery data for each segment and failing to meet the testing requirements for fracturing fracture well test analysis. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention discloses a method for testing the production profile of horizontal wells, which meets the requirements for production profile and pressure recovery testing, and has the advantages of low construction cost, high test success rate, high test efficiency and high test instrument recovery efficiency.

[0006] The technical solution adopted in this invention is a method for testing the production profile of horizontal wells, and the specific steps are as follows:

[0007] Step 1: Preparations before testing;

[0008] Step two, perform segmented sealing;

[0009] Step 3, Data Collection;

[0010] Step 4: Retrieve the logging instrument;

[0011] Step 5: Explain the product profile.

[0012] Furthermore, step one specifically includes programming the logging instrument before it is run in, setting the instrument delay start time according to the fracturing plan; numbering each logging instrument, corresponding to the well number, soluble bridge plug and its fracturing section, and writing this information into the memory of the corresponding logging instrument.

[0013] Furthermore, the logging instrument contains a soluble metal encapsulated in epoxy resin.

[0014] Furthermore, the density of the soluble metal is greater than the density of the well fluid.

[0015] Furthermore, the soluble metal is an aluminum-magnesium alloy or a magnesium-lithium alloy.

[0016] Further, step two specifically includes lowering a numbered logging instrument into the well according to the settings. The logging instrument's density is slightly greater than that of the well fluid. During fracturing, the logging instrument is lowered to the foot of the horizontal well, i.e., the starting position of the horizontal section, by its own weight before each fracturing stage. During fracturing, the logging instrument is pumped to the target horizontal section along with the fracturing fluid. Subsequently, on the surface, the cable end is connected to the perforating gun and the soluble bridge plug in sequence. During cluster perforation, the soluble bridge plug is transported to the position where the bridge plug needs to be set in the horizontal section as the fracturing fluid is pumped in by the pump truck. During this process, the previously lowered logging instrument is set in the target section along with the soluble bridge plug. The cable is then pulled up, and the previous steps are repeated until all soluble bridge plugs are set and the logging instrument is placed.

[0017] Furthermore, step three specifically includes collecting data after the logging tool is run into the well according to the instrument delay start time and sampling cycle set in the fracturing plan, and recording the temperature, pressure and acceleration data of the corresponding fracturing section downhole.

[0018] Furthermore, step four specifically includes the following steps: after the soluble bridge plug dissolves, the soluble metal of the logging instrument placed in each layer also dissolves. At this time, the density of the logging instrument is less than the density of the well fluid and floats in the well fluid, thus completing the recovery of the logging instrument.

[0019] Furthermore, step five specifically includes replaying and reading the test data from the memory using a computer, identifying the serial number of each logging instrument, and obtaining the production profile data collected by the logging instrument and the pressure recovery data of each fracturing section.

[0020] Furthermore, the production profile data includes temperature, pressure, and production data for each downhole section; the temperature and pressure data of the producing layer are directly obtained from the temperature and pressure data recorded by the logging tool, and the temperature and pressure data of the section to which each logging tool belongs are determined according to the logging tool number; the flow rate data of each producing layer is comprehensively judged by the instrument acceleration information and the time it takes for each logging tool to reach the vertical well section; subsequently, the pressure recovery data of each production section obtained by the logging tool is combined with well test analysis methods to calculate fracture parameters and reservoir parameters.

[0021] This invention discloses a method for testing the production profile of horizontal wells. Its beneficial effect is that by using a logging tool with soluble metal in combination with a perforating gun and a soluble bridge plug, it solves the technical problem of evaluating the fracturing effect of long horizontal wells, shortens the testing time of each section of the long horizontal well, and improves the testing success rate and testing efficiency. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 The diagram shown is a schematic of the logging instrument being lowered by its own weight in Example 1;

[0024] Figure 2 The diagram shown is a schematic of the well logging instrument placement process in Example 1;

[0025] Figure 3 The diagram shown is a schematic of the well logging instrument placement completed in Example 1;

[0026] Figure 4 The diagram shown is a schematic of the logging instrument and soluble metal in Example 1.

[0027] The attached diagram is labeled as follows: 1. Perforating gun; 2. Soluble bridge plug; 3. Logging instrument; 4. Cable; 5. Fracturing section; 6. Soluble metal. Specific implementation methods

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] To further understand the invention, the following detailed description, in conjunction with specific embodiments, further illustrates the invention.

[0030] Example 1: As Figures 1-4 As shown, a method for testing the production profile of a horizontal well is described. In this embodiment, three logging instruments 3 containing soluble metal 6 are deployed. The density of the logging instruments 3 containing soluble metal 6 is slightly greater than that of the well fluid. Specifically, the method includes:

[0031] Step 1: Pre-test preparations; specifically, this includes programming the logging instrument 3 before it is run in, setting the instrument's delayed start time according to the fracturing plan; numbering each logging instrument 3, corresponding to the well number, soluble bridge plug 2, and its fracturing segment 5, and writing this information into the memory of each logging instrument 3. The logging instrument 3 is then configured for sampling according to the fracturing design time phases, ensuring its data acquisition cycle matches the fracturing operation. From before the instrument is run into the well until the start of the corresponding fracturing segment 5, the instrument is in a dormant state, saving power and storage space. In this embodiment, the soluble metal 6 is an aluminum-magnesium alloy. It should be noted that the soluble metal only needs to have a density greater than the drilling fluid density and dissolve in the downhole electrolyte environment.

[0032] Step two involves segmented setting; specifically, the first logging instrument 3 is lowered into the well according to the settings. During fracturing, before each fracturing stage, the logging instrument 3 is lowered to the horizontal well foot (the starting position of the horizontal stage) by its own weight. During fracturing, the logging instrument 3 is pumped to the target horizontal stage along with the fracturing fluid. Subsequently, on the surface, the end of the cable 4 is connected sequentially to the perforating gun 1 and the soluble bridge plug 2. During cluster perforation, the soluble bridge plug 2 is transported to the position where the bridge plug needs to be set in the horizontal stage as the fracturing fluid is pumped in by the pump truck. During this process, the first logging instrument 3, which was lowered earlier, is set in the target stage along with the soluble bridge plug 2. The cable 4 is then pulled up and lowered back into the wellbore. The second logging instrument 3 is lowered into the well according to the settings. During the operation, before each fracturing section, the logging instrument 3 is lowered to the foot of the horizontal well (the starting position of the horizontal section) by its own weight. During fracturing, the logging instrument 3 is pumped to the target horizontal section along with the fracturing fluid. Then, on the surface, the end of the cable 4 is connected to the perforating gun 1 and the soluble bridge plug 2 in sequence. During the cluster perforation, the soluble bridge plug 2 is transported to the position of the bridge plug that needs to be set in the horizontal section as the fracturing fluid is pumped in by the pump truck. During this process, the previously lowered logging instrument 3 is set in the target section along with the soluble bridge plug 2. The above steps are repeated until the three soluble bridge plugs 2 are set and the logging instrument 3 is placed.

[0033] Step 3, data acquisition; specifically, after the logging tool 3 is run into the well, data is acquired according to the instrument delay start time and sampling cycle set in the fracturing plan, recording the temperature, pressure and acceleration data of the corresponding fracturing section 5 downhole, and storing the data in their respective memory.

[0034] Step four, recovery of logging tool 3; specifically, after a certain period of time following the completion of fracturing of all sections, the soluble bridge plug 2 and the soluble metal 6 of logging tool 3 dissolve and completely dissolve in the downhole electrolyte environment. At this time, the density of logging tool 3 is less than that of the well fluid, and the horizontal well fracturing fluid flowback stage begins. The downhole fluid reaches the wellhead under the action of formation pressure and flows back to the surface through the nozzle with a diameter of about 2mm and enters the surface oil production pipeline. During the fracturing fluid flowback, since the fracturing fluid and the formation produced fluid have a certain viscosity, and the density of logging tool 3 is slightly less than that of the well fluid, logging tool 3 is carried back to the surface by the fracturing fluid, thus completing the recovery of logging tool 3.

[0035] Step 5: Interpret the production profile. This specifically involves replaying and reading the test data from the memory using a computer, identifying the serial number of each logging tool 3 to obtain the production profile data collected by the logging tool 3 and the pressure recovery data of each fracturing section 5.

[0036] Furthermore, the production profile data includes temperature, pressure, and production data for each downhole segment; the temperature and pressure data of the producing segments are directly obtained from the temperature and pressure data recorded by the logging instrument 3, and the temperature and pressure data of each segment are determined according to the number of each logging instrument 3; the flow rate data of each producing segment are comprehensively judged by the instrument acceleration information and the time it takes for each logging instrument 3 to reach the vertical well section; subsequently, the pressure recovery data of each production segment obtained by the logging instrument 3 are combined with well test analysis methods to calculate fracture parameters and reservoir parameters.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for testing the production profile of a horizontal well, characterized in that, The specific steps are as follows: Step 1, pre-test preparations; the logging instrument (3) is encapsulated with soluble metal (6) through epoxy resin, and the density of the soluble metal (6) is greater than that of the well fluid. Step 2, segmented setting and sealing; specifically, the logging instrument (3) with the number attached is lowered into the well according to the setting. The density of the logging instrument (3) is greater than that of the well fluid. During construction, before fracturing each segment, the logging instrument (3) is lowered to the foot of the horizontal well by its own weight, that is, the starting position of the horizontal segment. During fracturing, the logging instrument (3) is pumped to the target horizontal segment along with the fracturing fluid. Then, on the ground, the end of the cable (4) is connected to the perforating gun (1) and the soluble bridge plug (2) in sequence. During the cluster perforation, the soluble bridge plug (2) is transported to the position of the bridge plug that needs to be set in the horizontal segment as the fracturing fluid is pumped in by the pump truck. During this process, the previously lowered logging instrument (3) is set in the target segment together with the soluble bridge plug (2). The cable (4) is pulled up and the previous steps are repeated until all the soluble bridge plugs (2) are set and the logging instrument (3) is placed. Step 3, data acquisition; specifically, after the logging instrument (3) is run into the well, data acquisition is carried out according to the instrument delay start time and sampling cycle set in the fracturing plan, and the temperature, pressure and acceleration data of the corresponding fracturing section (5) downhole are recorded; Step 4, recover the logging instrument; specifically, after the soluble bridge plug (2) is dissolved, the soluble metal (6) of the logging instrument (3) placed in each fracturing section (5) is also completely dissolved. At this time, the density of the logging instrument (3) is less than the density of the well fluid and floats in the well fluid, thus completing the recovery of the logging instrument (3). Step 5: Interpret the production profile. The production profile data includes temperature, pressure, and production data for each layer downhole. The temperature and pressure data of the producing layer are directly obtained from the temperature and pressure data recorded by the logging instrument (3). The temperature and pressure data of the layer in which each logging instrument (3) is located are determined according to the number of each logging instrument (3). The flow rate data of each producing layer is judged by comprehensively considering the instrument acceleration information and the time it takes for each logging instrument (3) to reach the vertical well section. Then, the pressure recovery data of each production layer obtained by the logging instrument (3) are used to calculate the fracture parameters and reservoir parameters in combination with the well test analysis method.

2. The method for testing the production profile of a horizontal well according to claim 1, characterized in that, Step 1 specifically includes programming the logging instrument (3) before it is run in, setting the instrument delay start time according to the fracturing plan; numbering each logging instrument (3) according to the well number, soluble bridge plug (2) and its fracturing section (5), and writing this information into the memory of the corresponding logging instrument (3).

3. The method for testing the production profile of a horizontal well according to claim 1, characterized in that, The soluble metal (6) is an aluminum-magnesium alloy or a magnesium-lithium alloy.

4. The method for testing the production profile of a horizontal well according to claim 1, characterized in that, Step 5 specifically includes replaying and reading the test data from the memory using a computer, identifying the number of each logging instrument (3), obtaining the production profile data collected by the logging instrument (3), and the pressure recovery data of each fracturing section (5).

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