Horizontal well temporary plugging fracturing simulation experiment device

Abstract

The invention belongs to the technical field of oil and gas field underground temporary plugging fracturing, and particularly relates to a horizontal well temporary plugging fracturing simulation experiment device. The horizontal well temporary plugging fracturing simulation experiment device comprises at least one fracture simulation unit used for simulating stratum fractures and a simulation wellbore installed on the fracture simulation unit in a penetrating mode, the simulation wellbore is provided with a simulation shot hole, the fracture simulation unit comprises at least two fracture simulation plates, and a simulation fracture is formed between the two fracture simulation plates. The simulation wellbore is communicated with the simulation crack through the simulation shot hole so as to convey a temporary plugging agent to the simulation crack, the pressure simulation unit is used for providing simulation formation closing pressure for the crack simulation unit, and the pressure simulation unit comprises pressure push plates arranged on the two sides of the crack simulation unit and a driving mechanism for driving the pressure push plates on the two sides to move oppositely. The pressure push plates on the two sides extrude the crack simulation plate through opposite movement to provide simulated formation closing pressure for the simulated crack, so that the simulated crack is closed, and the distribution state of the temporary plugging agent in the simulated crack is obtained.

Description

Technical Field

[0001] The present invention belongs to the technical field of downhole temporary plugging and fracturing in oil and gas fields, and particularly relates to a simulation experiment device for horizontal well temporary plugging and fracturing. Background Technique

[0002] In recent years, with the continuous development of oil and gas field exploitation in China, the exploration and development of oil and gas fields in China have entered the field of unconventional oil and gas exploration. However, the endowment of unconventional oil and gas resources is poor, and they generally have characteristics such as tight reservoirs, low porosity, and low permeability. It is necessary to carry out reservoir fracturing transformation to achieve economic and effective development. Among them, the horizontal well segmented fracturing technology has become the main technology for unconventional oil and gas development. The temporary plugging and diversion fracturing technology pumps in degradable temporary plugging agents, that is, the temporary plugging agents are carried into the reservoir fractures by the fracturing fluid, and plugs are generated at the fracture ends or narrow fracture widths, thereby generating high fracture net pressure. When the net pressure exceeds the fracture pressure of the weak part in the main fracture, the fracture initiation orientation will change, forming new branch fractures or communicating more microfractures, thus forming a complex fracture network to maximize the reservoir stimulation effect.

[0003] During the fracturing process of horizontal wells, the migration of temporary plugging agents under the action of complex mechanisms seriously affects their placement morphology in the fractures, increasing the difficulty of fracturing design. Therefore, clarifying the migration law of temporary plugging agents in horizontal well fracturing and improving the understanding of their hydrodynamic behavior during the migration process are of great significance for guiding fracturing design. At present, there is a lack of a suitable simulation experiment device, making it difficult to effectively carry out the evaluation and optimization of the temporary plugging process and guide the design of the process plan.

[0004] Chinese invention patent with application publication number CN113533680A discloses an experimental device and method for simulating downhole temporary plugging and fracturing experiments. The experimental device includes: a plurality of flat fracture mechanisms, which include two spaced-apart and enclosed flat plates and a cylindrical perforation mechanism, with a simulated fracture formed between the two flat plates, and the perforation mechanism is provided with a plurality of perforations communicating with the simulated fracture; a plurality of horizontally arranged wellbores connected in sequence and passing through the flat fracture mechanism; a circulation pump, with the simulated fracture and the horizontally arranged wellbore respectively communicating with the circulation pump.

[0005] After analysis, it is found that this solution is carried out under the condition of pressure balance during specific application. Due to ignoring the influence of formation closure pressure on the experimental process, there will be certain errors in the experimental results. Summary of the Invention

[0006] The purpose of the present invention is to provide a simulation experiment device for horizontal well temporary plugging and fracturing to solve the problem that the existing simulation experiment device for horizontal well temporary plugging and fracturing has certain errors in experimental results due to ignoring the influence of formation closure pressure during application.

[0007] To achieve the above object, a horizontal well temporary plugging and fracturing simulation experiment device provided by the present invention adopts the following technical solution:

[0008] A horizontal well temporary plugging and fracturing simulation experiment device includes at least one fracture simulation unit for simulating formation fractures and a simulation wellbore installed in the fracture simulation unit. The simulation wellbore has simulation perforations. The fracture simulation unit includes at least two fracture simulation plates. A simulation fracture is formed between the two fracture simulation plates. The simulation wellbore communicates with the simulation fracture through the simulation perforations to deliver a temporary plugging agent to the simulation fracture. It also includes a pressure simulation unit for providing a simulated formation closing pressure to the fracture simulation unit. The pressure simulation unit includes pressure push plates arranged on both sides of the fracture simulation unit and a driving mechanism for driving the pressure push plates on both sides to move towards each other. The pressure push plates on both sides squeeze the fracture simulation plates through the opposite movement to provide a simulated formation closing pressure for the simulation fracture, so that the simulation fracture closes to obtain the distribution state of the temporary plugging agent in the simulation fracture.

[0009] The beneficial effects of the above technical solution are as follows: Based on the improvement of the prior art, the horizontal well temporary plugging and fracturing simulation experiment device of the present invention is provided with a pressure simulation unit for providing a simulated formation closing pressure to the fracture simulation unit. The pressure simulation unit includes pressure push plates arranged on both sides of the fracture simulation unit and a driving mechanism for driving the pressure push plates on both sides to move towards each other. The pressure push plates on both sides squeeze the fracture simulation plates through the opposite movement to provide a simulated formation closing pressure for the simulation fracture, so that the simulation fracture closes to obtain the distribution state of the temporary plugging agent in the simulation fracture. The simulated formation closing pressure for the simulation fracture is generated by the opposite movement of the pressure push plates. The pressure push plates push the fracture simulation plates to move relative to each other to close the simulation fracture, so that the temporary plugging agent in the simulation fracture diffuses along the simulation fracture, and then the distribution state of the temporary plugging agent in the simulation fracture is obtained. Since the influence of the formation closing pressure is fully considered during the experiment, the result of the distribution state of the temporary plugging agent obtained by the experiment of the present invention is more accurate and reliable.

[0010] Further, the pressure push plate is a flat plate, and the driving mechanism has double output ends that can move towards and away from each other. The double output ends are respectively connected to the pressure push plates through clamping arms.

[0011] The beneficial effects of the above technical solution are as follows: The flat pressure push plate is easy to cooperate with the fracture simulation unit to transfer the pressure of the pressure module unit; the driving mechanism that can move towards or away from each other and has double output ends is respectively connected to the pressure push plates through clamping arms, so that the simulation fracture can be provided with a simulated layer closing pressure by squeezing the fracture simulation plates through the opposite movement, in order to more accurately simulate the state of the actual formation, thereby improving the accuracy and reliability of the result.

[0012] Further, the clamping arm is L-shaped.

[0013] The beneficial effects of the above technical solution are as follows: The L-shaped clamping arm has a simple structure, is convenient for assembly, and is easy to transfer the pressure generated by the driving mechanism to the pressure push plate.

[0014] Further, the driving mechanism is a hydraulic cylinder or a pneumatic cylinder. The hydraulic cylinder is connected with a hydraulic control system or the pneumatic cylinder is connected with a pneumatic control system to apply a specified closing pressure to the simulated fracture.

[0015] The beneficial effects of the above technical solution are as follows: The driving mechanism using a hydraulic cylinder or a pneumatic cylinder has a compact structure, operates stably, has less impact and vibration, is easy to realize frequent starting and commutation actions, and is simple to operate. The hydraulic control system or the pneumatic control system controls the driving mechanism to apply a specified closing pressure to the simulated fracture, so that the influence of the closing pressure of the formation on the temporary plugging effect can be simulated as required, which is beneficial to improving the accuracy of the simulation experiment results; at the same time, on the premise of ensuring the experimental requirements, it also avoids damage to the fracture simulation plate due to excessive closing pressure.

[0016] Further, a push plate through hole for the simulated wellbore to pass through is provided on the pressure push plate, and the simulated wellbore is passed through the push plate through hole.

[0017] The beneficial effects of the above technical solution are as follows: The simulated wellbore passes through the push plate through hole and is installed in the fracture simulation unit, so that the pressure push plate and the fracture simulation plate are coaxially installed, and the pressure push plate is more easily matched with the fracture simulation plate, thereby effectively transferring the pressure of the pressure simulation unit.

[0018] Further, the fracture simulation unit further includes a fixing frame, the fracture simulation plate is installed on the fixing frame, and an adjusting mechanism for providing a force to resist deformation for the fracture simulation plate is provided between the fixing frame and the fracture simulation plate.

[0019] The beneficial effects of the above technical solution are as follows: The fixing frame provides stable support for the fracture simulation plate during the experiment, and the adjusting mechanism provided between the fixing frame and the fracture simulation plate is used to provide a force to resist deformation for the fracture simulation plate, so that the module fracture is in a controllable state.

[0020] Further, the adjusting mechanism is a spring mounted between the fracture simulation plate and the fixing frame, and there are at least two springs arranged on both sides of the simulated wellbore.

[0021] The beneficial effects of the above technical solution are as follows: By providing a spring mounted between the fracture simulation plate and the fixing frame, a force to resist deformation can be provided for the fracture simulation plate, so that the width of the simulated fracture can be in a relatively controllable state; at least two springs arranged on both sides of the simulated wellbore can effectively ensure the balanced force on the fracture simulation plates on both sides of the simulated wellbore.

[0022] Further, the fracture simulation plate includes a fracture simulation plate main body and reinforcing ribs provided on the fracture simulation plate main body.

[0023] The beneficial effects of the above technical solution are as follows: The crack simulation plate composed of the crack simulation plate body and the reinforcing ribs arranged on the crack simulation plate body can effectively simulate the formation, while ensuring the pressure-bearing capacity and stability of the crack simulation plate, making the experimental structure more reliable.

[0024] Furthermore, the crack simulation plate includes a crack simulation plate body, and the crack simulation plate body is a multi-layer structure, at least including a porous plate on the outermost layer and a permeable plate with permeation ability in the middle layer.

[0025] The beneficial effects of the above technical solution are as follows: The crack simulation plate body with a multi-layer composite structure can more effectively simulate the formation, making the experimental results more reliable; the porous plate on the outermost layer provides support for the permeable plate in the middle layer, and at the same time facilitates the crack simulation plate to overflow the working medium permeated through the permeable plate through the porous plate during the experiment.

[0026] Furthermore, the crack simulation plate further includes reinforcing ribs, and the reinforcing ribs are arranged on the porous plate on the outermost layer of the crack simulation plate body.

[0027] The beneficial effects of the above technical solution are as follows: The reinforcing ribs can prevent the structure of the crack simulation plate from deforming during the experiment, improving the pressure-bearing capacity and stability of the crack simulation plate; at the same time, setting the reinforcing ribs on the porous plate on the outermost layer of the crack simulation plate body facilitates the forming and processing of the reinforcing ribs and the crack simulation plate body. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the horizontal well temporary plugging and fracturing simulation experimental device of the present invention;

[0029] Figure 2 It is a schematic diagram of the pressure simulation unit in the present invention;

[0030] Figure 3 It is a schematic diagram of the crack simulation unit in the present invention.

[0031] In the figure: 1, delivery pump; 2, simulation wellbore; 3, injection unit; 4, pressure simulation unit; 5, crack simulation unit; 6, water storage tank; 7, pipeline;

[0032] 41, power system; 42, drive system; 43, first clamping arm; 44, pressure push plate; 45, second clamping arm; 441, push plate through hole;

[0033] 50, simulated crack; 51, crack simulation plate; 52, fixing frame; 511, crack simulation plate body; 512, reinforcing rib; 513, transition plate; 521, fixing frame; 522, spring; 523, base; 524, simulation plate through hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The features and performance of the present invention will be further described in detail in conjunction with the embodiments below.

[0035] Embodiment 1 of the horizontal well temporary plugging and fracturing simulation experimental device in the present invention:

[0036] Most of the simulation experimental devices for the migration law of temporary plugging agents in current horizontal well fracturing are carried out under the condition of pressure balance. Due to ignoring the influence of formation closure pressure on the experimental process, there will be certain errors in the experimental results.

[0037] To solve the above problems, the present invention provides a horizontal well temporary plugging and fracturing simulation experimental device, which includes at least one fracture simulation unit for simulating formation fractures and a simulation wellbore installed in the fracture simulation unit. The simulation wellbore has simulation perforations. The fracture simulation unit includes at least two fracture simulation plates, and a simulation fracture is formed between the two fracture simulation plates. The simulation wellbore communicates with the simulation fracture through the simulation perforations to deliver the temporary plugging agent to the simulation fracture. It also includes a pressure simulation unit for providing the simulation formation closure pressure for the fracture simulation unit. The pressure simulation unit includes pressure push plates arranged on both sides of the fracture simulation unit and a driving mechanism for driving the pressure push plates on both sides to move towards each other. The pressure push plates on both sides squeeze the fracture simulation plates through the opposite movement to provide the simulation formation closure pressure for the simulation fracture, so that the simulation fracture closes to obtain the distribution state of the temporary plugging agent in the simulation fracture.

[0038] The horizontal well temporary plugging and fracturing simulation experimental device of the present invention is provided with a pressure simulation unit for providing the simulation formation closure pressure for the fracture simulation unit. The pressure simulation unit includes pressure push plates arranged on both sides of the fracture simulation unit and a driving mechanism for driving the pressure push plates on both sides to move towards each other. The pressure push plates on both sides squeeze the fracture simulation plates through the opposite movement to provide the simulation formation closure pressure for the simulation fracture, so that the simulation fracture closes to obtain the distribution state of the temporary plugging agent in the simulation fracture. By the opposite movement of the pressure push plates, the simulation formation closure pressure for the simulation fracture is generated. The pressure push plates push the fracture simulation plates to move relative to each other to close the simulation fracture, so that the temporary plugging agent in the simulation fracture diffuses along the simulation fracture, and then the distribution state of the temporary plugging agent in the simulation fracture is obtained. Since the influence of formation closure pressure is fully considered in the experimental process, the experimental results of the distribution state of the temporary plugging agent obtained by the present invention are more accurate and reliable.

[0039] As Figure 1 shown, the present invention provides a horizontal well temporary plugging and fracturing simulation experimental device, and the experimental device includes a delivery pump 1, a simulation wellbore 2, a filling unit 3, a pressure simulation unit 4, a fracture simulation unit 5 and a water storage tank 6.

[0040] In this embodiment, there are multiple fracture simulation units 5 for simulating formation fractures; there are multiple pressure simulation units 4 arranged corresponding to the fracture simulation units 5 for providing simulated formation closing pressure for the fracture simulation units 5; the simulated wellbore 2 is installed through the fracture simulation units 5 and the pressure simulation units 4; the transfer pump 1 is used to pump the fracturing fluid carrying the temporary plugging agent into the simulated wellbore 2 and the fracture simulation units 5. The input end of the transfer pump 1 is connected to the water storage tank 6 through the pipeline 7, and the output end of the transfer pump 1 is connected to the input end of the simulated wellbore 2; the output end of the simulated wellbore 2 is connected to the water storage tank 6 through the pipeline 7; a dosing unit 3 for injecting the temporary plugging agent into the simulated wellbore 2 is further arranged at the input end of the simulated wellbore 2. In this way, the transfer pump 1, the simulated wellbore 2, and the water storage tank 6 form a circulation loop through the pipeline 7. The underground formation fractures and their states are simulated through the simulated wellbore 2, the fracture simulation units 5, and the pressure simulation units 4, and the temporary plugging agent is put in through the dosing unit 3 and enters the simulated wellbore 2 and the fracture simulation units 5 along with the fracturing fluid in the circulation loop to temporarily plug the simulated fracture 50, so as to simulate the temporary plugging fracturing experiment.

[0041] In this embodiment, the transfer pump 1 is a constant pressure and constant speed pump, and the dosing unit 3 is a funnel device.

[0042] In this embodiment, the simulated wellbore 2 provides a flow passage for the fracturing fluid containing the temporary plugging agent. The barrel wall of the simulated wellbore 2 is made of transparent pressure-resistant material to evaluate the wellbore migration performance of the temporary plugging agent under different pumping conditions. A plurality of simulated perforations are arranged on the barrel wall of the simulated wellbore 2. The simulated wellbore 2 communicates with the simulated fracture 50 through the simulated perforations. Specifically, each simulated perforation is connected to a simulated fracture 50 to transport the temporary plugging agent to the simulated fracture 50 through the simulated perforations.

[0043] In this embodiment, there are three fracture simulation units 5 arranged. Correspondingly, there are also three pressure simulation units 4; the three fracture simulation units 5 are arranged at equal intervals along the axial direction of the simulated wellbore 2; in other embodiments, the three fracture simulation units 5 can also be arranged non-uniformly along the axial direction of the simulated wellbore 2.

[0044] As Figure 3As shown in the figure, the crack simulation unit 5 includes a crack simulation plate 51, a fixing frame 52, and an adjusting mechanism disposed between the fixing frame 52 and the crack simulation plate 51 for providing a force to resist deformation for the crack simulation plate 51. In this embodiment, the adjusting mechanism is a spring 522. The crack simulation plate 51 is installed in the fixing frame 52, and the spring 522 is mounted between the crack simulation plate 51 and the fixing frame 52. Specifically, a crack simulation unit 5 includes two first crack simulation plates and a second crack simulation plate that are spaced apart from each other, and a fixing frame 52 for installing the crack simulation plate 51. In this embodiment, the fixing frame 52 is integrally in the shape of a square frame. The fixing frame 52 includes a base 523 and a fixing frame 521 disposed on the base 523. The fixing frame 521 includes a top plate and a bottom plate that are spaced apart and parallel to each other, and two side frames that are spaced apart and parallel to each other. The first crack simulation plate and the second crack simulation plate are spaced apart in the space enclosed by the side frames, the top plate, and the bottom plate. The upper and lower ends of the first crack simulation plate and the second crack simulation plate are hermetically connected through auxiliary plates, so that there is a certain interval between the first crack simulation plate and the second crack simulation plate. The peripheries of the first crack simulation plate and the second crack simulation plate are closed, so as to form a simulated crack 50 between the first crack simulation plate and the second crack simulation plate. A transition plate 513 is vertically connected to the auxiliary plate, and the transition plate 513 is fixedly connected to the top plate and the bottom plate respectively.

[0045] In this embodiment, two springs 522 corresponding to one crack simulation plate 51 are provided and are distributed on both sides of the simulated wellbore 2. Specifically, springs 522 are respectively provided on both sides of the simulated wellbore 2. One end of the spring 522 is disposed on the crack simulation plate 51, and the other end is disposed at the middle of the opposite side frame of the fixing frame 521 of the fixing frame 52. It can be understood that in one simulated crack unit 5, the springs 522 are symmetrically arranged in pairs along the simulated crack 50. In other embodiments, the number of springs 522 corresponding to one crack simulation plate 51 can be set to four, six, or other appropriate numbers. Preferably, the number of springs 522 should be set to an even number and symmetrically distributed on the side frames. By providing springs between the crack simulation plate and the fixing frame, a force to resist deformation can be provided for the crack simulation plate, so that the width of the simulated crack is in a controllable state. At the same time, the springs cooperate with the pressure simulation unit to realize the dynamic compression expansion of the width of the simulated crack and can also realize a fixed crack.

[0046] In this embodiment, the width of the simulated crack 50 changes with the pumping pressure of the delivery pump. The closing of the simulated crack 50 is controlled by the pressure simulation unit, and the reinforcing ribs control the balance and stability of the crack simulation plate 51. As the pumping pressure increases, the spring 522 is compressed and contracted, and the simulated crack 50 expands dynamically.

[0047] The crack simulation plate 51 includes a crack simulation plate main body 511 and reinforcing ribs 512 disposed on the crack simulation plate main body 511. The crack simulation plate main body 511 is rectangular. The reinforcing ribs 512 include longitudinal reinforcing ribs and transverse reinforcing ribs, and the longitudinal reinforcing ribs and the transverse reinforcing ribs are arranged in a grid pattern intersecting each other on the surface of the crack simulation plate main body 511 facing away from the simulated crack 50.

[0048] In this embodiment, the crack simulation plate main body 511 is a multi-layer structure and has a certain deformation ability. Its outermost layer is a porous transparent acrylic plate, and the middle layer is a transparent material with strong permeability. The edges of the crack simulation plate 51 are sealed by gluing to prevent liquid leakage. The specific composition of the crack simulation plate 51 can set the thickness of each layer of material according to the needs of the experiment to simulate different seepage velocities; the crack simulation plate made of transparent material can directly observe the distribution state of the temporary plugging agent in the simulated crack, which is beneficial to the observation and evaluation of the distribution state of the temporary plugging agent during the simulation experiment.

[0049] In this embodiment, the reinforcing ribs 512 are glued to the outer surface of the crack simulation plate main body 511. Specifically, the reinforcing ribs 512 are glued to the surface of the outermost layer of the crack simulation plate main body 511 facing away from the simulated crack 50. In this embodiment, the reinforcing ribs 512 are glued to the surface of the acrylic plate of the outermost layer of the crack simulation plate main body 511 to prevent the structural deformation of the crack simulation plate and resulting imbalance during the experiment.

[0050] In this embodiment, a simulation plate through-hole 524 for the simulation wellbore 2 to pass through is provided at the center of the crack simulation plate 51. The crack simulation plate 51 is sleeved outside the simulation wellbore 2 through the simulation plate through-hole 524, and the simulation perforations of the simulation wellbore 2 are communicated with the simulated crack 50. The connection between the simulation plate through-hole 524 and the simulation wellbore 2 is sealed.

[0051] As Figure 2 shown, the pressure simulation unit 4 includes a pressure simulation mechanism and a driving mechanism. Specifically, the driving mechanism includes a driving system 42 and a power system 41 for providing a driving source for the driving system 42. A pressure simulation mechanism is connected to the driving system 42. The pressure simulation mechanism includes pressure push plates 44 disposed on both sides of the crack simulation unit 5 and clamping arms for transmitting pressure to the pressure push plates 44. The two pressure push plates 44 are arranged oppositely; the driving system 42 has double output ends capable of moving towards and away from each other, and the double output ends are respectively connected to the pressure push plates 44 through the clamping arms. One end of the clamping arm is connected to the pressure push plate 44, and the other end is connected to the driving system 42; in this embodiment, the pressure push plate is a flat plate.

[0052] The drive system 42 drives the relatively arranged pressure push plates 44 to move towards each other; the clamping arms include a relatively arranged first clamping arm 43 and a second clamping arm 45. The drive system 42 can drive the first clamping arm 43 and the second clamping arm 45 to drive the pressure push plates 44 to approach or move away from each other, so as to provide a simulated formation closing pressure to the simulated crack 50.

[0053] In this embodiment, the power system 41 is a hydraulic system or a pneumatic system, and in other embodiments, it can also be an electric system; correspondingly, the drive system 42 is a hydraulic cylinder or a pneumatic cylinder, and in other embodiments, it can also be an electric push rod or a nut screw mechanism; the power system 41, the drive system 42, and the assembly structure of the clamping arms and the drive system 42 are all prior arts and are not limited in this embodiment.

[0054] In this embodiment, the hydraulic cylinder is connected with a hydraulic control system or the pneumatic cylinder is connected with a pneumatic control system to apply a specified closing pressure to the simulated crack 50.

[0055] In this embodiment, the structures of the first clamping arm 43 and the second clamping arm 45 are the same, and they are both L-shaped rod-shaped clamping arms. In other embodiments, the first clamping arm 43 and the second clamping arm 45 can be L-shaped plate-shaped clamping arms, or they can be Y-shaped clamping arms.

[0056] In order to enhance the stability of the clamping arms in transmitting pressure, the number of the first clamping arms 43 and the second clamping arms 45 is set to be multiple, and multiple first clamping arms 43 and second clamping arms 45 are arranged side by side at intervals. In this embodiment, both the first clamping arm 43 and the second clamping arm are set to be two.

[0057] The pressure push plates 44 are respectively connected to the surface of the crack simulation plate body of the crack simulation plate 51 facing away from the simulated crack 50. Thus, when the power system 41 provides power, the drive system 42 drives the clamping arms to move horizontally to drive the pressure push plates 44 to move towards each other. The pressure push plates 44 drive the crack simulation plate 51 to clamp the simulated crack 50 to simulate the formation closing pressure, so that the simulated crack 50 is closed to obtain the distribution state of the temporary plugging agent in the simulated crack 50. In this way, the simulated formation closing pressure for the simulated crack 50 is generated by the opposite movement of the pressure push plates 44, and the pressure push plates 44 push the crack simulation plate 51 to move relatively to close the simulated crack 50, so that the temporary plugging agent in the simulated crack 50 diffuses along the simulated crack 50, and then the distribution state of the temporary plugging agent in the simulated crack 50 is obtained. Since the influence of the formation closing pressure is fully considered during the experiment, the result of the distribution state of the temporary plugging agent obtained by the experiment of the present invention is more accurate and reliable.

[0058] In this embodiment, in order to facilitate the cooperation with the crack simulation plate 51, a push plate through hole 441 for the simulated wellbore 2 to pass through is provided at the center of the pressure push plate 44, and the simulated wellbore 2 passes through the push plate through hole 441.

[0059] In this embodiment, the horizontal well temporary plugging and fracturing simulation experimental device further includes a control unit and a sensor unit (not shown in the figure). The control unit is connected to the driving mechanism of the pressure simulation unit 4 in a controlled manner. The control unit controls the driving mechanism to apply simulated pressure according to the requirements specified by the control unit based on the information collected by the sensor unit, so as to prevent damage to the fracture simulation plate while ensuring the experimental requirements.

[0060] In this embodiment, the sensor unit may include a pressure sensor and a displacement sensor disposed on the simulated fracture 50. The sensor and the control unit are both prior arts and will not be elaborated herein.

[0061] Based on the structure of the above horizontal well temporary plugging and fracturing simulation experimental device, during the experiment, a preset amount of temporary plugging agent is injected into the simulated wellbore 2 through the injection unit 3. The temporary plugging agent enters the simulated wellbore 2 along with the fracturing fluid transported by the delivery pump 1 and enters the simulated fracture 50 through the simulated perforations. Under the action of the pressure simulation unit 4, the simulated fracture 50 is closed. After the fracturing fluid in the simulated fracture 50 seeps out through the fracture simulation plate 51, the distribution law of the temporary plugging agent in the simulated fracture 50 and the plugging condition at the position of the simulated perforations can be directly observed through the transparent fracture simulation plate 51. Record the parameters detected by the control unit, and combine the distribution state of the temporary plugging agent in the simulated fracture 50 and the simulated perforations to judge the plugging result, thereby completing the simulated temporary plugging and fracturing experiment.

[0062] Embodiment 2 of the horizontal well temporary plugging and fracturing simulation experimental device in the present invention:

[0063] In Embodiment 1 of the horizontal well temporary plugging and fracturing simulation experimental device, the pressure push plate is a flat plate. In this embodiment, the pressure push plate is a plate-like structure with uneven surfaces. Specifically, the surface of the pressure push plate facing the fracture simulation plate has an uneven structure.

[0064] Embodiment 3 of the horizontal well temporary plugging and fracturing simulation experimental device in the present invention:

[0065] In Embodiment 1 of the horizontal well temporary plugging and fracturing simulation experimental device, the clamping arm is L-shaped. In this embodiment, the clamping arm is arc-shaped.

[0066] Embodiment 4 of the horizontal well temporary plugging and fracturing simulation experimental device in the present invention:

[0067] In Embodiment 1 of the horizontal well temporary plugging and fracturing simulation experimental device, a push plate through hole for the simulated wellbore to pass through is provided on the pressure push plate, and the simulated wellbore passes through the push plate through hole. In this embodiment, no push plate through hole is provided on the pressure push plate. Specifically, the pressure push plate is no longer sleeved on the simulated wellbore, but the pressure push plate is set as a split structure or has a structural form for avoiding the simulated wellbore.

[0068] Example 5 of the horizontal well temporary plugging and fracturing simulation experiment device in the present invention:

[0069] In Example 1 of the horizontal well temporary plugging and fracturing simulation experiment device, the adjusting mechanism is a spring mounted on top between the fracture simulation plate and the fixing frame. In this embodiment, the adjusting mechanism is a device with telescopic ability, for example, it can be a telescopic cylinder or a telescopic hydraulic cylinder.

[0070] Example 6 of the horizontal well temporary plugging and fracturing simulation experiment device in the present invention:

[0071] In Example 1 of the horizontal well temporary plugging and fracturing simulation experiment device, the fracture simulation plate is a multi-layer structure, at least including a porous plate on the outermost layer and a permeable plate with permeation ability in the middle layer. In this embodiment, the fracture simulation plate is a single-layer structure, specifically, it can be glass with a certain pressure-bearing capacity.

[0072] Example 7 of the horizontal well temporary plugging and fracturing simulation experiment device in the present invention:

[0073] In Example 1 of the horizontal well temporary plugging and fracturing simulation experiment device, reinforcing ribs are also provided on the fracture simulation plate. In this embodiment, the reinforcing ribs are no longer provided; specifically, the pressure-bearing capacity and stability of the fracture simulation plate are improved by increasing the thickness of the fracture simulation plate or replacing the material of the fracture simulation plate.

[0074] Example 8 of the horizontal well temporary plugging and fracturing simulation experiment device in the present invention:

[0075] In Example 1 of the horizontal well temporary plugging and fracturing simulation experiment device, an adjusting mechanism for providing a force to resist deformation for the fracture simulation plate is provided between the fixing frame and the fracture simulation plate. In this embodiment, the adjusting mechanism is no longer provided.

[0076] The above is only the preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention is subject to the claims. All equivalent structural changes made by using the description and drawings of the present invention shall be equally included in the protection scope of the present invention.

Claims

1. A horizontal well temporary plugging and fracturing simulation experimental device, comprising at least one fracture simulation unit for simulating formation fractures and a simulated wellbore installed in the fracture simulation unit, wherein the simulated wellbore has a simulated blasthole, the fracture simulation unit comprises at least two fracture simulation plates, a simulated fracture is formed between the two fracture simulation plates, and the simulated wellbore is connected to the simulated fracture through the simulated blasthole to transport a temporary plugging agent to the simulated fracture, characterized in that: It also includes a pressure simulation unit for providing simulated formation closure pressure for the fracture simulation unit. The pressure simulation unit includes pressure push plates arranged on both sides of the fracture simulation unit and a driving mechanism for driving the pressure push plates on both sides to move toward each other. The pressure push plates on both sides squeeze the fracture simulation plates by moving toward each other to provide simulated formation closure pressure for the simulated fracture, so that the simulated fracture is closed, thereby obtaining the distribution state of the temporary plugging agent in the simulated fracture.

2. The horizontal well temporary plugging and fracturing simulation experimental device according to claim 1 is characterized in that: The pressure push plate is a flat plate, and the driving mechanism has double output ends that can move toward and away from each other, and the double output ends are respectively connected to the pressure push plate through clamping arms.

3. The horizontal well temporary plugging and fracturing simulation experimental device according to claim 2 is characterized in that: The clamping arm is L-shaped.

4. The horizontal well temporary plugging and fracturing simulation experimental device according to claim 2, characterized in that: The driving mechanism is a hydraulic cylinder or a pneumatic cylinder, and the hydraulic cylinder is connected to a hydraulic control system or the pneumatic cylinder is connected to a pneumatic control system to apply a specified closing pressure to the simulated crack.

5. The horizontal well temporary plugging and fracturing simulation experimental device according to any one of claims 1 to 4, characterized in that: The pressure push plate is provided with a push plate through hole for the simulated wellbore to pass through, and the simulated wellbore is passed through the push plate through hole.

6. The horizontal well temporary plugging and fracturing simulation experimental device according to any one of claims 1 to 4, characterized in that: The crack simulation unit also includes a fixing frame, the crack simulation plate is mounted on the fixing frame, and an adjustment mechanism for providing the crack simulation plate with a force to resist deformation is arranged between the fixing frame and the crack simulation plate.

7. The horizontal well temporary plugging and fracturing simulation experimental device according to claim 6 is characterized in that: The regulating mechanism is a spring mounted between the fracture simulation plate and the fixing frame. There are at least two springs arranged on both sides of the simulation wellbore.

8. The horizontal well temporary plugging and fracturing simulation experimental device according to any one of claims 1 to 4, characterized in that: The crack simulation plate comprises a crack simulation plate body and reinforcing ribs arranged on the crack simulation plate body.

9. The horizontal well temporary plugging and fracturing simulation experimental device according to any one of claims 1 to 4, characterized in that: The crack simulation plate comprises a crack simulation plate body, which is a multi-layer structure and at least comprises a porous plate in the outermost layer and a permeable plate with permeability in the middle layer.

10. The horizontal well temporary plugging and fracturing simulation experimental device according to claim 9, characterized in that: The crack simulation plate also includes reinforcing ribs, which are arranged on the outermost porous plate of the crack simulation plate body.

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