Interface fluid channeling simulation test device and method considering initial perforation damage

Abstract

The invention discloses an interface fluid channeling simulation test device and method considering perforation initial damage, and belongs to the technical field of oil and gas exploitation, and the interface fluid channeling simulation test device considering perforation initial damage comprises an inner cylinder assembly, an outer cylinder assembly, a cement sheath body, a container assembly and a perforating gun. The simulation casing pipe and the simulation rock which are matched with the casing pipe component and the rock component in size are designed to form the inner cylinder assembly and the outer cylinder assembly so as to achieve simulation of the shaft structure, and the cement sheath body and the perforating gun are arranged in the filling interval between the inner cylinder assembly and the outer cylinder assembly so as to achieve simulation of the shaft structure. Construction of the test device in an initial damage environment can be achieved, simulation of shaft hydraulic pressure can be achieved by simulating injection of liquid in a first injection interval in a casing pipe based on the constructed test device, and fluid is injected into a first interface, a second interface and a second injection interval through a container assembly. Therefore, the interface fluid channeling simulation test considering the initial damage of the perforation is completed.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas extraction technology, specifically relating to an interface crossflow simulation test device and method that considers initial perforation damage. Background Technology

[0002] Currently, oil and gas extraction is gradually moving towards deeper oil and gas reservoirs. 70% of newly added crude oil reserves are low-permeability reservoirs, which greatly increases the difficulty of oil and gas extraction. Conventional extraction methods can no longer meet the needs of commercial production. In order to improve the production of tight deep oil and gas reservoirs, horizontal well multi-stage fracturing technology has been applied to drilling and production engineering. As an efficient reservoir stimulation measure, this technology has been widely used in the production of deep oil and gas reservoirs.

[0003] In the process of multi-stage fracturing in horizontal wells, interfacial crossflow directly affects the fracturing effect and the integrity of the wellbore seal. Therefore, preventing crossflow between fracturing stages is crucial. To maintain good sealing of the cement sheath, it is necessary to conduct research on the crossflow patterns at the casing-cement sheath interface and the cement sheath-formation interface during hydraulic fracturing and production enhancement operations. This will allow for the optimization of fracturing fluid design and the selection of optimal cement slurry systems. Existing research has provided a detailed explanation of the crossflow theory and the causes of crossflow during fracturing operations, and has also given anti-crossflow measures. However, before fracturing operations, perforation will cause initial damage to the wellbore structure, and existing research has not considered the impact of the interfacial damage to the wellbore structure after perforation on the occurrence of crossflow. Summary of the Invention

[0004] The purpose of this invention is to provide an interfacial crossflow simulation test device and method that takes into account the initial damage of the perforation, so as to overcome the shortcomings of the existing research mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an interface crossflow simulation test device considering initial perforation damage, comprising:

[0006] The inner cylinder assembly includes a simulated sleeve that internally defines a first injection zone and a sleeve component that internally defines a second injection zone.

[0007] A sealing member is disposed at the connection position between the simulated sleeve and the sleeve member, and separates the first injection interval and the second injection interval in the axial direction;

[0008] An outer cylinder assembly is disposed radially outside the inner cylinder assembly, and a filling interval is defined between the inner cylinder assembly and the outer cylinder assembly. The outer cylinder assembly includes simulated rock and rock components connected by a connecting structure.

[0009] A cement ring is disposed within the filling interval. A first interface is defined between the inner wall of the cement ring and the outer wall of the inner cylinder assembly, and a second interface is defined between the outer wall of the cement ring and the inner wall of the outer cylinder assembly.

[0010] The first and second sealing components are respectively assembled at both ends of the outer cylinder assembly along the axial direction;

[0011] A container assembly configured to supply liquid and / or gas to the first injection zone, the second injection zone, the first interface, and the second interface;

[0012] A perforating gun configured to create radially extending channels in casing components, cement annular structures, and rock components;

[0013] A hoop component is fitted onto the rock component.

[0014] Furthermore, both the simulated casing and the simulated rock are made of transparent material.

[0015] Furthermore, the container assembly includes a first water tank and a first pipeline, wherein the first pipeline is a connecting pipeline between the first water tank and the first injection section.

[0016] Furthermore, the container assembly also includes a second water tank, a gas tank, and a second pipeline, the second pipeline comprising:

[0017] The first flow section has a first end connected to the gas tank and a second end extending away from the first end, and the second water tank is connected to the first flow section;

[0018] At least three second flow sections, each of which is a connecting pipe to the second end of the first flow section and the second injection interval, the first interface, or the second interface.

[0019] Furthermore, the simulation testing device also includes a first strain gauge disposed between the contact surface of the casing component and the cement ring, and a second strain gauge disposed between the rock component and the cement ring.

[0020] Furthermore, the simulation testing device also includes a first flow sensor disposed between the simulated casing and the cement ring, and a second flow sensor disposed between the simulated rock and the cement ring.

[0021] Furthermore, the connection structure is a flange structure.

[0022] Furthermore, both the first and second sealing components are flange bodies.

[0023] Furthermore, the simulation testing device also includes a camera assembly, which includes a camera device placed within the first injection interval and a camera control module disposed outside the first injection interval for controlling the camera device and acquiring data.

[0024] Another aspect of this application discloses an interfacial crossflow simulation test method considering initial perforation damage. The method is implemented based on the aforementioned apparatus and includes:

[0025] Liquid is injected into the first injection zone to simulate wellbore hydraulic pressure;

[0026] Cement grout is injected into the filling area to form a cement ring;

[0027] The perforating gun is controlled to form radially extending channels in casing components, cement annulus and rock components, and the channels are closed radially outward by a hoop structure.

[0028] Liquid was injected into the first interface, the second interface (and the second injection interval), and experimental data were observed and collected.

[0029] Furthermore, the method also includes injecting gas into the second injection zone, the first interface, and the second interface for airtightness testing before injecting liquid into the first injection zone to simulate wellbore hydraulic pressure.

[0030] Compared with the prior art, the beneficial effects of the present invention are:

[0031] This application simulates the wellbore structure by designing a simulated casing and simulated rock that match the dimensions of the casing and rock components. This simulates the inner and outer cylinder components. By setting a cement ring and a perforation gun in the filling interval between the inner and outer cylinder components, a test device under initial damage conditions can be constructed. Based on the constructed test device, the wellbore hydraulic pressure can be simulated by injecting liquid into the first injection interval inside the casing. Fluid is injected into the first interface, the second interface, and the second injection interval using a container assembly to complete the interface flow simulation test considering the initial damage of perforation. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall testing device;

[0033] Figure 2 Schematic diagram of the outer cylinder assembly and the inner cylinder assembly;

[0034] Figure 3 This is a schematic diagram of a container component;

[0035] Figure 4 This is a three-dimensional schematic diagram of the testing device.

[0036] 100. Inner cylinder assembly; 101. Sleeve assembly; 102. First injection zone; 103. Simulated sleeve; 104. Second injection zone; 105. Sealing component;

[0037] 200. Outer cylinder assembly; 201. Rock component; 202. Simulated rock; 203. Filling section; 204. Connection structure;

[0038] 300. Cement ring; 301. First interface; 302. Second interface;

[0039] 400. First closure component; 401. Second closure component;

[0040] 500, Container assembly; 501, First water tank; 502, First pipeline; 503, Pump; 504, Valve; 505, Second water tank; 506, Gas tank; 507, Second pipeline; 507a, First flow section; 507b, Second flow section; 511, Pressure gauge;

[0041] 600. First strain gauge; 601. Second strain gauge; 602. Strain gauge; 603. Strain signal processing system;

[0042] 700. First flow sensor; 701. Second flow sensor;

[0043] 800. Perforation gun; 801. Hole; 802. Hoop component;

[0044] 900. Camera assembly; 901. Camera device; 902. Camera control module. Detailed Implementation

[0045] 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. 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.

[0046] An interfacial crossflow simulation test device considering initial perforation damage, referring to Figure 2 It includes an inner cylinder assembly 100 and an outer cylinder assembly 200, both of which are configured as hollow cylinders extending along axis O. In some embodiments, refer to... Figure 2The inner cylinder assembly 100 includes a simulated sleeve 103 and a sleeve component 101. The simulated sleeve 103 and the sleeve component 101 respectively define a first injection interval 102 and a second injection interval 104. That is, the simulated sleeve 103 defines a first injection interval 102, and the sleeve component 101 defines a second injection interval 104. The simulated sleeve 103 and the sleeve component 101 are in axial contact at one end. At the same time, the simulation test device is provided with a sealing component 105 at the connection position of the simulated sleeve 103 and the sleeve component 101. The first injection interval 102 and the second injection interval 104 are separated by the sealing component 105.

[0047] Back Figure 2 and combined Figure 4 Continuing with the description of the simulation testing device, the outer cylinder assembly 200 includes a simulated rock 202 and a rock component 201. The simulated rock 202 and the rock component 201 are in contact at one end along their axial direction and are connected by a connecting structure 204. In some embodiments, the connecting structure 204 is configured as a flange structure, that is, the simulated rock 202 and the rock component 201 are both provided with connecting bosses at the connection position, and the connecting bosses on the simulated rock 202 and the rock component 201 are connected by fasteners such as bolts, thereby realizing the connection between the simulated rock 202 and the rock component 201.

[0048] Furthermore, the outer cylinder assembly 200 is disposed radially outside the inner cylinder assembly 100, and correspondingly defines a filling interval 203 between the outer cylinder assembly 200 and the inner cylinder assembly 100. Correspondingly, the simulation test device also includes a cement ring 300, which fills the filling interval 203. The cement ring 300 has an inner wall surface that contacts the outer wall surface of the inner cylinder assembly 100 and an outer wall surface that contacts the inner wall surface of the outer cylinder assembly 200. A first interface 301 is defined between the inner wall surface of the cement ring 300 and the outer wall surface of the inner cylinder assembly 100, and a second interface 302 is defined between the outer wall surface of the cement ring 300 and the inner wall surface of the outer cylinder assembly 200. Furthermore, the simulated sleeve 103 and the simulated rock 202 are both made of transparent pressure-resistant material to allow observation of the state of the first interface 301, the second interface 302, and the cement ring 300 during the test.

[0049] Reference Figure 1The aforementioned simulation testing device also includes a first sealing member 400 and a second sealing member 401 respectively assembled at both axial ends of the outer cylinder assembly 200. Based on the first sealing member 400 and the second sealing member 401, the first injection interval 102, the second injection interval 104, the first interface 301 and the second interface 302 can be defined in the axial direction to form a closed first injection interval 102, the second injection interval 104, the first interface 301 and the second interface 302. In some examples, the first sealing member 400 and the second sealing member 401 are both configured as flange bodies. Correspondingly, both axial ends of the outer cylinder assembly 200 are provided with connecting bosses. The first sealing member 400 and the second sealing member 401 are connected to the boss structures at both axial ends of the outer cylinder assembly 200 by fasteners such as bolts to realize the connection between the outer cylinder assembly 200 and the first sealing member 400 and the second sealing member 401.

[0050] Reference Figure 2 and Figure 3 The aforementioned simulation testing apparatus further includes a container assembly 500, which is fluidly connected to the first injection section 102, the second injection section 104, the first interface 301, and the second interface 302, and configured to supply liquid and / or gas to the first injection section 102, the second injection section 104, the first interface 301, and the second interface 302. In some embodiments, the container assembly 500 includes a first water tank 501, a second water tank 505, and a gas tank 506, and is connected to the first water tank 501 and the second water tank 505. The first pipeline 502 and the second pipeline 507 are used in conjunction with the gas tank 506. One end of the first pipeline 502 is connected to the first water tank 501, and the other end passes through the first closure 400 and extends into the first injection section 102. That is, the first closure 400 has a hole for the first pipeline 502 to pass through, and the first pipeline 502 is equipped with a pump 503 and a valve (not shown). The liquid (e.g., water) in the first water tank 501 can flow into the first injection section 102 along the first pipeline 502 under the action of the pump on the first pipeline 502.

[0051] Continue to refer to Figure 3The second pipeline 507 includes a first flow section 507a and at least three second flow sections 507b. The first flow section 507a has a first end connected to the gas tank 506 and a second end extending away from the first end. The second water tank 505 is connected to the first section. Correspondingly, one end of a single second flow section 507b is connected to the second end of the first flow section 507a, and the other end passes through the second closure 401 and communicates with the first interface 301, the second interface 302, or the second injection section 104. For example, when the second pipeline 507 includes three second flow sections 507b, one end of a single second flow section 507b is fluidly connected to the first interface 301, the second interface 302, and the second injection section 104, respectively, to achieve liquid and / or gas supply in the first interface 301, the second interface 302, and the second injection section 104. Figure 3 The second pipeline 507 is equipped with a pump 508 and a safety valve 509. Each second flow section 507b is equipped with a valve and a pressure gauge (not shown). Based on the control of the pump and valve on the second pipeline 507, the injection control of fluid in the first interface 301, the second interface 302 and the second injection interval 104 can be realized.

[0052] In some embodiments, the above-mentioned simulation testing device further includes a perforating gun 800. Based on the function of the perforating gun 800, radially extending channels 801 can be generated on the casing component 101, cement ring 300 and rock component 201. In practical applications, considering engineering needs, a spiral perforation method is adopted for perforation operations. Correspondingly, the above-mentioned simulation testing device also includes a hoop component 802, which is sleeved on the rock component 201 and configured to close the radial outer end of the channel 801 to ensure the sealing of the first interface 301, the second interface 302 and the second injection interval 104 during the test.

[0053] Reference Figure 3 The aforementioned simulation testing device further includes a first flow sensor 700 and a second flow sensor 701. The first flow sensor 700 is installed between the contact surfaces of the simulated sleeve 103 and the cement ring 300 and is configured to detect the fluid flow rate at the first interface 301. The second flow sensor 701 is installed between the contact surfaces of the simulated rock 202 and the cement ring 300 and is configured to detect the fluid flow rate at the second interface 302.

[0054] Reference Figure 3The aforementioned simulation testing device further includes a first strain gauge 600 and a second strain gauge 601. The first strain gauge 600 is installed between the contact surfaces of the sleeve component 101 and the cement ring 300, and the second strain gauge 601 is installed between the contact surfaces of the rock component 201 and the water ring. Based on the first strain gauge 600 and the second strain gauge 601, the strain generated by the cement ring 300 can be calculated. Furthermore, both the first strain gauge 600 and the second strain gauge 601 are connected to an external strain gauge 602 and a strain signal processing system 603 to process the strain data.

[0055] Reference Figure 2 The aforementioned simulation testing device also includes a camera assembly 900, which includes a camera device 901 disposed within the first injection interval 102 and a camera control module 902 disposed outside the first injection interval 102 for controlling the camera device 901 and acquiring data.

[0056] In actual operation, the assembly process of the above-mentioned simulation test device is as follows:

[0057] Step 1: Fix the rock component 201 and the casing component 101 onto the second sealing component 401, and place simulated rock 202 and simulated casing 103 corresponding to the size of rock component 201 and casing component 101 at one end of the axial direction of rock component 201 and casing component 101, and fit the hoop component 802 onto rock component 201, and connect simulated rock 202 and rock component 201 through flange structure.

[0058] Step 2: Gas is injected into the first interface 301, the second interface 302 and the second injection interval 104 through the gas tank 506 and the second pipeline 507 to perform airtightness testing.

[0059] Step 3: Install a first strain gauge 600 between the contact surfaces of the casing component 101 and the cement ring 300, and a second strain gauge 601 between the rock component 201 and the cement ring 300 to detect the deformation of the cement ring 300. Install a first flow sensor 700 between the simulated casing 103 and the cement ring 300, and a second flow sensor 701 between the simulated rock 202 and the cement ring 300 to measure the flow velocity of the cross-flowing fluid. At the same time, inject fluid into the first injection interval 102 through the first water tank 501 and the first pipeline 502 to simulate the liquid pressure inside the wellbore.

[0060] Step 4: Prepare a certain amount of cement slurry according to the ratio, inject the cement slurry into the filling section 203 through the injection port on the first sealing member 400 and let it stand for solidification. After the cement slurry solidifies in the device, install the first sealing member 400, and at the same time apply pressure to the radial outside of the rock component 201 to simulate the actual geological environment.

[0061] Step 5: Prepare for perforation operation. Considering the actual perforation project, a spiral perforation method is adopted for perforation operation. The perforation gun 800 and cable are inserted from the second sealing member 401 of the device to perforate and obtain the channel 801. Then the perforation gun 800 and cable are pulled out. The channel 801 is sealed by the hoop member 802. The strain information of the cement ring 300 is collected by the first strain gauge 600 and the second strain gauge 601.

[0062] Step 6: Insert the camera device 901 into the first injection zone 102 from the upper flange inlet of the device, turn on the camera device 901, and prepare to observe the flow phenomenon during the fracturing process.

[0063] Step 7: Prepare for fracturing operation. Use the pump on the second pipeline 507 to pump water at a constant pressure into the first interface 301 and the second interface 302 to replace the fracturing fluid during the fracturing process. Use the camera device 901 to observe whether there is any cross-flow phenomenon.

[0064] This application also proposes an interface crossflow simulation test method considering initial perforation damage, the method being implemented based on the above-mentioned simulation test device and including:

[0065] Liquid is injected into the first injection zone 102 to simulate wellbore hydraulic pressure;

[0066] Cement grout is injected into the filling section 203 to form a cement ring 300;

[0067] The perforating gun 800 is controlled to form a radially extending channel 801 on the casing member 101, the cement ring 300 and the rock member 201, and the radial outer side of the channel 801 is closed by the hoop member 802.

[0068] Fluid is injected into the first interface 301, the second interface 302 and the second injection interval 104, and experimental data are observed and collected.

[0069] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An interfacial crossflow simulation test device considering initial perforation damage, characterized in that, include: The inner cylinder assembly (100) includes a simulated sleeve (103) that internally defines a first injection zone (102) and a sleeve member (101) that internally defines a second injection zone (104); A sealing member (105) is disposed at the connection position between the simulated sleeve (103) and the sleeve member (101) and separates the first injection interval (102) and the second injection interval (104) in the axial direction; An outer cylinder assembly is disposed radially outside the inner cylinder assembly (100), and a filling interval (203) is defined between the inner cylinder assembly (100) and the outer cylinder assembly (200). The outer cylinder assembly includes a simulated rock (202) and a rock component (201) connected by a connecting structure (204). A cement ring (300) is disposed within the filling interval (203). A first interface (301) is defined between the inner wall surface of the cement ring (300) and the outer wall surface of the inner cylinder assembly (100), and a second interface (302) is defined between the outer wall surface of the cement ring (300) and the inner wall surface of the outer cylinder assembly. The first closure (400) and the second closure (401) are respectively assembled at both ends of the outer cylinder assembly along the axial direction; A container assembly (500) configured to supply liquid and / or gas to the first injection zone (102), the second injection zone (104), the first interface (301), and the second interface (302); A perforating gun (800) configured to create radially extending channels (801) in the casing member (101), the cement ring (300), and the rock member (201); The hoop component (802) is fitted onto the rock component (201).

2. The interface crossflow simulation test device considering initial perforation damage according to claim 1, characterized in that: Both the simulated sleeve (103) and the simulated rock (202) are made of transparent material.

3. The interface crossflow simulation test device considering initial perforation damage according to claim 1, characterized in that: The container assembly (500) includes a first water tank (501) and a first pipeline (502), wherein the first pipeline (502) is a connecting pipeline between the first water tank (501) and the first injection section (102).

4. The interface flow simulation test device considering initial perforation damage according to claim 1, characterized in that: The container assembly (500) further includes a second water tank (505), a gas tank (506), and a second pipeline (507), the second pipeline (507) comprising: A first flow section (507a) has a first end connected to the gas tank (506) and a second end extending away from the first end, and the second water tank (505) is connected to the first flow section (507a). At least three second flow sections (507b), each second flow section (507b) being a connecting pipe to the second end of the first flow section (507a) and the second injection interval (104), the first interface (301), or the second interface (302).

5. The interface crossflow simulation test device considering initial perforation damage according to claim 1, characterized in that: The simulation testing device also includes a first strain gauge (600) disposed between the contact surfaces of the casing component (101) and the cement ring (300) and a second strain gauge (601) disposed between the rock component (201) and the cement ring (300).

6. The interface flow simulation test device considering initial perforation damage according to claim 1, characterized in that: The simulation testing device also includes a first flow sensor (700) disposed between the simulated sleeve (103) and the cement ring (300) and a second flow sensor (701) disposed between the simulated rock (202) and the cement ring (300).

7. The interface crossflow simulation test device considering initial perforation damage according to claim 1, characterized in that: The connection structure (204) is a flange structure.

8. The interface crossflow simulation test device considering initial perforation damage according to claim 1, characterized in that: Both the first sealing element (400) and the second sealing element (401) are flange bodies.

9. The interface crossflow simulation test device considering initial perforation damage according to claim 1, characterized in that: The simulation test device further includes a camera assembly (900), which includes a camera device (901) placed in the first injection interval (102) and a camera control module (902) disposed outside the first injection interval (102) for controlling the camera device (901) and acquiring data.

10. A method for simulating interfacial crossflow considering initial perforation damage, the method being implemented based on the simulation testing apparatus according to any one of claims 1-9, the method comprising: Liquid is injected into the first injection zone (102) to simulate wellbore hydraulic pressure; Cement grout is injected into the filling section (203) to form a cement ring (300); The perforating gun (800) is controlled to form a radially extending channel (801) on the casing member (101), the cement ring (300) and the rock member (201), and the radial outer side of the channel (801) is closed by the hoop member (802). Liquid was injected into the first interface (301), the second interface (302), and the second injection interval (104), and experimental data were observed and collected.

11. The interface crossflow simulation test method considering initial perforation damage according to claim 10, characterized in that: The method further includes injecting gas into the second injection zone (104), the first interface (301), and the second interface (302) for airtightness testing before injecting liquid into the first injection zone (102) to simulate wellbore hydraulic pressure.

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