Thin difference layer rock core preparation device and preparation method

Abstract

The invention discloses a thin difference layer rock core preparation device and a thin difference layer rock core preparation method, and belongs to the technical field of rock core preparation, the preparation device comprises a thin difference layer rock core preparation mold, a thin difference layer rock core contour plate and a hydraulic machine, a cut rock core slice is placed in the thin difference layer rock core preparation mold in a constant temperature heater, and the thin difference layer rock core contour plate is placed in the hydraulic machine; the hydraulic machine presses a core slice through the thin difference layer core contour plate, and a curing agent is atomized through the atomizing and spraying assembly and then sprayed to the core slice; the preparation method comprises the steps of core slice preparation, curing agent atomization, pressurization and curing agent spraying. Repeatedly pressurizing and spraying the curing agent every time a layer of core slice is placed until the core slices are stacked and pressed into a thin difference layer core; and finally taking out the thin-difference layer rock core and curing in a drying oven. A hydraulic machine is used for simulating the pressure environment of a real stratum, and meanwhile it is ensured that each rock core slice can be evenly sprayed with a curing agent; the permeability of the prepared thin-difference layer core is tested, and the fluid channeling between thin-difference reservoirs is quantified.

Description

Technical Field

[0001] The invention belongs to the technical field of core preparation, and in particular relates to a device and a method for preparing a thin-layer core. Background Art

[0002] The preparation of artificial cores has important experimental significance in the fields of geology, petroleum, mining and engineering. It can not only effectively simulate the complex underground geological environment, but also provide researchers with precise and controllable experimental materials to deeply explore the physical and chemical properties of rocks and their performance under different environmental conditions.

[0003] However, the preparation of thin-layer cores still faces many challenges. Unlike conventional core production, thin-layer cores often have complex layered structures, with significant differences in lithology, porosity, permeability, etc. between layers. The preparation of thin-layer cores can simulate this geological structure with thin layer changes, providing oilfield experts with an experimental platform for studying the interface transition between rock layers, interlayer differences, and changes in the physical properties of different lithology layers. This is of great significance for reservoir evaluation in oil and gas exploration.

[0004] In the process of preparing thin and differential layer cores, a common method is to use existing cores and bond different types of rocks into a multi-layer structure with adhesives. However, this method has some disadvantages. First, the cores made by conventional stacking methods are prone to structural instability under high displacement pressure differences, and it is difficult to reproduce the relationship of the real pore throat structure. In addition, conventional methods are also difficult to achieve the production of ultra-thin core slices, such as core slices with a thickness of only 1 mm. Moreover, the use of adhesives may affect the physical properties between rocks, such as porosity and permeability. Therefore, the traditional method of preparing thin and differential layer cores has certain limitations in meeting the needs of complex reservoir structures. It is particularly necessary to carry out research on thin and differential layer core preparation technology. Summary of the invention

[0005] The purpose of the present invention is to provide a thin layer core preparation device and a preparation method, aiming to solve the technical problem that the existing experimental devices and methods are difficult to accurately simulate the ultra-thin layer in the thin layer core.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: A thin-layer core preparation device comprises a thin-layer core making mold, a thin-layer core pressure plate and a hydraulic press, wherein the thin-layer core making mold is arranged in a constant temperature heater, the inner cavity of the thin-layer core making mold can accommodate cut core slices, and the thin-layer core pressure plate is arranged just above the opening of the thin-layer core making mold; a temperature and pressure controller for controlling the temperature and pressure in the thin-layer core making mold is arranged in the hydraulic press, and an atomizing spraying component is arranged in the hydraulic press for atomizing a curing agent and spraying it into the core slice in the thin-layer core making mold; the constant temperature heater is arranged in a base, and the hydraulic press is arranged on the top of the base.

[0007] Preferably, the atomizing spray assembly includes an atomizer and an atomizing spray head, the atomizer is arranged at the top of the hydraulic press, the atomizing spray head is arranged at the bottom of the hydraulic press, the outlet of the atomizer is connected to the atomizing spray head through a pipeline; the upper end of the atomizer is connected to the height adjustment frame.

[0008] Preferably, a drying box is also included, and the core in the thin layer core making mold is pressurized and then taken out and placed in the drying box for curing.

[0009] Preferably, the core slices are cut from core raw materials by a core cutting machine, and the core raw materials include quartz sand of different mesh sizes and a binder. The quartz sand of different mesh sizes and the binder are beaten and stirred with a double hammer mixer for 30 to 50 minutes to obtain a variety of homogenized core raw materials corresponding to the mesh sizes of the quartz sand.

[0010] Preferably, the mesh sizes of the quartz sand are 10-20 mesh, 20-40 mesh, 40-60 mesh, 60-100 mesh, 100-200 mesh and above 200 mesh, respectively, and the binder includes epoxy resin and polyester.

[0011] Preferably, the double-hammer mixer includes a stirring frame, a control panel, a stirring double hammer and a raw material tank, the raw material tank is used to contain quartz sand and binder, the upper ends of the stirring double hammers are connected to the control panel, the control panel is connected to the stirring frame, and the control panel controls the stirring double hammers to beat and stir the quartz sand and binder in the raw material tank; the material of the stirring double hammers is rubber.

[0012] Preferably, the core cutting machine includes a spiral pressurizer and a cutting knife, the homogenized core raw material is put into the mold of the spiral pressurizer, and the core raw material is pressed into the shape of the mold by rotating the pressurizing rod; a scale and a height adjustment button are provided on the outer wall of the spiral pressurizer, the cutting knife is arranged on the opposite side of the scale, the cutting knife is connected to the height adjustment button, and the height of the cutting knife is adjusted by the height adjustment button; a conveyor belt is provided at the bottom of the scale, and the conveyor belt is used to transport the cut core slices out.

[0013] The present invention also provides a method for preparing a thin-layer core, which uses the above-mentioned thin-layer core preparation device to prepare a thin-layer core, comprising the following steps: Preparation of core slices: Pre-prepare several core slices of the same or different shapes and thicknesses; Preheating and atomization: Start the constant temperature heater to preheat the core slices in the thin layer core making mold, and start the atomization spray component to pre-atomize the curing agent; Pressurizing and spraying curing agent: put the first layer of core slices into the mold for making thin and poor layer cores, and use a hydraulic press to simulate the formation pressure to pressurize the first layer of core slices for 5-50 minutes and then release the pressure; then spray the curing agent on the surface of the first layer of core slices through the atomizing spray component; Placing the second layer of core slices on the first layer of core slices, and repeating the above steps of pressurizing and spraying the curing agent; Each time a layer of core slices is placed, the above-mentioned pressurization and spraying of curing agent need to be repeated until the core slices are stacked and pressed into the required thin layer core; After the thin and poor layer core is pressed, the pressurization is stopped, and the thin and poor layer core is taken out and put into the oven for curing.

[0014] Preferably, the permeability test is performed on the solidified thin and poor layer core to quantify the crossflow between the thin and poor reservoirs; Under the physical property conditions of simulating natural thin and poor formations, the influence rules of core permeability corresponding to different quartz sand mesh numbers are as follows: y = -0.0004x 3 +0.1966x 2 -30.843x + 1532.5 Where: y—permeability, 10 -3 , um 2 ; x—quartz sand mesh number, mesh.

[0015] Preferably, the preparation process of the core slice is as follows: Prepare quartz sand and binder of different mesh sizes, sieve the quartz sand and inject it into the raw material tank with the binder, start the double hammer agitator, beat and stir to obtain a variety of homogenized core materials corresponding to the mesh sizes of the quartz sand; The homogenized core material is placed in a core cutting machine, and the core materials with different permeabilities are cut into core slices with the same shape and the same or different thicknesses.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention ensures the required temperature for the preparation of thin-layer cores by a constant temperature heater, and uses a hydraulic press to pressurize the core slices in the mold for making thin-layer cores, which can simulate the pressure environment in the real formation; the curing agent is atomized by the atomizing spray component and then sprayed into the mold for making thin-layer cores, ensuring that each layer of core slices can be evenly sprayed with the curing agent; the pressed thin-layer cores are taken out for drying and curing, and the core permeability is experimentally tested to achieve the quantification of the crossflow characterization method between thin-layer reservoirs. The present invention has the advantages of simple structure, high precision, and low energy consumption. It not only realizes the preparation of millimeter-level ultra-thin cores, but also can achieve the quantification of the crossflow characterization method between thin-layer reservoirs by simulating parameters such as core permeability; it helps to better control the structure and physical properties of thin-layer cores, and has important guiding significance for oilfield exploitation and subsequent process and construction parameter optimization. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0018] In the attached picture: Figure 1 A schematic structural diagram of a thin-layer core preparation device provided in an embodiment of the present invention; Figure 2 Schematic diagram of the structure of a double-hammer agitator in an embodiment of the present invention; Figure 3 It is a structural schematic diagram of a core cutting machine in an embodiment of the present invention; Figure 4 This is the corresponding relationship diagram between the number of quartz sand meshes and the core permeability; In the figure: 1- mold for making thin and differential layer cores; 2- press plate for thin and differential layer cores; 3- hydraulic press; 4- constant temperature heater; 5- temperature and pressure controller; 6- base; 7- atomizer; 8- atomizing spray head; 9- height adjustment frame; 10- stirring frame; 11- control panel; 12- stirring double hammers; 13- raw material tank; 14- spiral pressurizer; 15- cutting knife; 16- scale; 17- height adjustment knob; 18- conveyor belt; 19- display. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and Examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In the following detailed description of the present invention, some specific details are described in detail. However, for the parts not described in detail, those skilled in the art can also fully understand the present invention.

[0020] In addition, those skilled in the art should understand that the drawings are only provided to illustrate the purpose, features and advantages of the present invention, and the drawings are not actually drawn to scale.

[0021] At the same time, unless the context clearly requires otherwise, the words "include", "comprises" and similar words throughout the specification and claims should be interpreted as inclusive rather than exclusive or exhaustive; that is, the meaning is "including but not limited to".

[0022] like Figure 1 As shown, a thin-layer core preparation device comprises a thin-layer core making mold 1, a thin-layer core corrugated plate 2 and a hydraulic press 3, wherein the thin-layer core making mold 1 is arranged in a constant temperature heater 4, the inner cavity of the thin-layer core making mold 1 can accommodate cut core slices, and the thin-layer core corrugated plate 2 is arranged just above the opening of the thin-layer core making mold 1; a temperature and pressure controller 5 for controlling the temperature and pressure in the thin-layer core making mold is arranged in the hydraulic press 3, and an atomizing spraying component is arranged in the hydraulic press 3 for atomizing a curing agent and spraying it onto the core slice in the thin-layer core making mold 1; the constant temperature heater 4 is arranged in a base 6, and the hydraulic press 3 is arranged on the top of the base 6. The atomizing spray assembly includes an atomizer 7 and an atomizing spray head 8, wherein the atomizer 7 is arranged at the top of the hydraulic press 3, the atomizing spray head 8 is arranged at the bottom of the hydraulic press 3, the outlet of the atomizer 7 is connected to the atomizing spray head 8 through a pipeline; the upper end of the atomizer 7 is connected to the height adjustment frame 9. The cut core slice is placed in a thin layer core making mold, preheated by a constant temperature heater, and the hydraulic press is started to apply pressure to it to simulate the pressure environment in the real formation; the atomized curing agent is sprayed on each layer of the core slice, and the core slice is placed again and pressurized to bond and fix it together.

[0023] In the specific design, the thin-layer core profile plate is connected to the screen monitor, and the temperature and pressure inside the thin-layer core production mold can be monitored and controlled in real time through the display 19 during the process of the hydraulic press pressing the core slice. At the same time, a container for curing agent is set at the inlet of the atomizer 7, and an atomizing sheet is installed in the atomizer 7, and the outlet end is connected to the hydraulic press. The atomized curing agent can be connected to the atomizing spray head 8 through the spraying pipeline inside the hydraulic press, and the atomized curing agent can be sprayed onto the core slice in the thin-layer core production mold 1 through the atomizing spray head 8. The temperature and pressure controller 5 continuously transmits electrical signals to the hydraulic press, and obtains the real-time temperature and pressure conditions through the sensor.

[0024] During the specific production process, a drying box (not shown) is also included. After the thin-layer core in the thin-layer core production mold is pressurized and formed, it is taken out and placed in the drying box for curing.

[0025] Wherein, the core slice is cut from the core raw material by a core cutting machine, and the core raw material includes quartz sand of different meshes and a binder, and the quartz sand of different meshes is beaten and stirred with the binder by a double hammer mixer for 30 to 50 minutes to obtain a variety of homogenized core raw materials corresponding to the mesh numbers of the quartz sand. Wherein, the mesh numbers of the quartz sand are 10 to 20 meshes, 20 to 40 meshes, 40 to 60 meshes, 60 to 100 meshes, 100 to 200 meshes and above 200 meshes, and the binder includes epoxy resin and polyester. It is a prior art to prepare cores using quartz sand and a binder, and the specific ratio is not within the scope of protection of the present invention, and will not be repeated here. It depends on the prepared core conditions and is proportioned according to the physical properties of the simulated formation, and each core is different. For example, a core with a permeability of 200mD requires preparation according to a ratio of 40 to 60 mesh quartz sand: binder of 9:1.

[0026] In a specific embodiment of the present invention, Figure 2 As shown, the double hammer agitator includes a stirring frame 10, a control panel 11, a stirring double hammer 12 and a raw material tank 13. The raw material tank 13 is used to contain quartz sand and binder. The upper end of the stirring double hammer 12 is connected to the control panel 11, and the control panel 11 is connected to the stirring frame 10. The control panel 11 controls the stirring double hammer 12 to beat and stir the quartz sand and binder in the raw material tank 13. The stirring double hammer is detachably connected, the material of the stirring double hammer 12 is rubber, and the raw material tank 13 is a steel product. When used, the specified mesh size of quartz sand and the required binder are injected into the raw material tank; the control panel controls the stirring double hammer to switch the stirring hammer function, and the quartz sand and binder in the raw material tank are homogenized.

[0027] In the specific design, the top of the stirring double hammer is connected to the lifting rod of the lifting component, and the lifting action of the stirring double hammer at the lower end of the lifting component is controlled by the control panel to repeatedly beat the quartz sand and binder in the raw material tank; at the same time, the lifting component is connected to the output shaft of the motor, and the start and stop of the motor is controlled by the control panel to realize the rotation of the stirring double hammer. Among them, the lifting component can be a cylinder, a hydraulic cylinder or an electric push rod, etc., which can realize the up and down lifting of the stirring double hammer. There are multiple knives radially arranged on the outer surface of the stirring double hammer. During the rotation process, the stirring double hammer uses multiple knives to cut the core raw materials with higher viscosity, thereby realizing the homogenization of quartz sand and binder.

[0028] In a specific embodiment of the present invention, Figure 3As shown, the core cutter includes a screw press 14 and a cutter 15. The homogenized core raw material is put into the mold of the screw press 14, and the core raw material is pressed into the shape of the mold by rotating the press rod; a scale 16 and a height adjustment button 17 are provided on the outer wall of the screw press 14, and the cutter 15 is arranged on the opposite side of the scale 16. The cutter 15 is connected to the height adjustment button 17, and the height of the cutter 15 is adjusted by the height adjustment button 17; a conveyor belt 18 is provided at the bottom of the scale 16, and the conveyor belt 18 is used to convey the cut core slices out. The cutter adopts a diamond core cutter and is installed horizontally, which can cut the core raw material extruded from the bottom of the mold into core slices. The homogenized core raw material is put into the core cutter, and the core raw materials with different permeabilities are cut into core slices of the same shape, the same thickness or different thicknesses; the height of the cutter 15 is accurately controlled by the scale 16.

[0029] During specific production, the spiral pressurizing instrument 14 includes a tubular mold, a T-shaped pressurizing rod and a template at its bottom. A plugging cover is provided on the top of the mold, and the pressurizing rod and the plugging cover are threadedly matched; the height adjustment button 17 is coaxially fixed with the internal gear, the gear is meshed with the rack installed inside, and the cutting knife 15 is fixed to the lower end of the rack, and the rack is driven up and down by rotating the height adjustment button 17, thereby adjusting the height of the cutting knife 15. At the same time, the cutting knife 15 is connected to the hydraulic rod, and the hydraulic rod drives the cutting knife 15 to move in the horizontal direction, thereby cutting the bottom of the core material into core slices. During application, after adjusting the height of the cutting knife using the height adjustment button, the pressurizing rod is rotated to move it downward, and the core material is squeezed using the template so that the core material is squeezed out from the bottom of the mold in sequence; the hydraulic rod is used to drive the cutting knife to extend and retract, and the core material is cut in sequence from bottom to top.

[0030] The present invention also provides a method for preparing a thin-layer core, which uses the above-mentioned thin-layer core preparation device to prepare a thin-layer core, comprising the following steps: (1) Preparation of core slices: Prepare several core slices of the same or different shapes and thicknesses in advance. The specific thickness can be adjusted according to the test requirements. The preparation process of core slices is as follows: Prepare quartz sand and binder of different mesh sizes, sieve the quartz sand and inject it into the raw material tank 13 with the binder, start the double hammer agitator, beat and stir to obtain a variety of homogenized core raw materials corresponding to the mesh sizes of the quartz sand; The homogenized core material is placed in a core cutting machine, and the core materials with different permeabilities are cut into core slices with the same shape and the same or different thicknesses.

[0031] (2) Preheating and atomization: Start the constant temperature heater 4 to preheat the core slice in the thin layer core making mold 1, and start the atomizer 7 to pre-atomize the curing agent; (3) Pressurization and spraying of curing agent: The first layer of core slices is placed in the thin layer core making mold 1, and the hydraulic press 3 simulates the formation pressure (0-50MPa) to pressurize the first layer of core slices for 5-50 minutes and then releases the pressure; then the atomized curing agent is sprayed on the surface of the first layer of core slices through the atomizing spray head. During the experiment, the hydraulic press 3 will display and record key information such as temperature, pressure, and pressurization time in real time; the display 19 will provide a visual interface for data such as the stress and temperature changes of the core slices, and adjust in real time to ensure that the environment during the entire experiment is consistent with the actual formation conditions.

[0032] Placing the second layer of core slices on the first layer of core slices, and repeating the above steps of pressurizing and spraying the curing agent; Each time a layer of core slices is placed, the above-mentioned pressurization and spraying of curing agent need to be repeated until the core slices are stacked and pressed into the required thin layer core; After the thin and poor layer core is pressed, the pressurization is stopped, and the thin and poor layer core is taken out and put into the oven for curing.

[0033] By observing and testing the thin core slices of the solidified thin layer, the changes in its physical properties can be analyzed.

[0034] After the experiment, turn off the power switches of all devices.

[0035] The thickness and permeability of the core thin layer are defined as follows. The value depends on the thickness of the small core thin slice in the simulated natural thin formation and the natural underground pressure. The corresponding permeability of each small core thin slice after simulation is also different. The simulation data is shown in the following table:

[0036] The thickness Ai and permeability Ki of the core slice in this table are the core data of the simulated formation, which are filled in by the test personnel.

[0037] Under simulated formation pressure conditions, multiple physical property experiments were conducted, the permeability of the solidified thin layer core was tested, the crossflow between the thin layer was quantified, and the influence of different quartz sand mesh numbers on the core permeability was obtained, such as Figure 4 The influence of different quartz sand mesh numbers on core permeability is as follows: y = -0.0004x 3 +0.1966x 2 -30.843x + 1532.5 Where: y—permeability, 10 -3 , um 2 ; x—quartz sand mesh number, mesh.

[0038] In summary, the present invention ensures the required temperature for the preparation of thin-layer cores through a constant temperature heater, and uses a hydraulic press to pressurize the core slices in the mold for making thin-layer cores, so as to simulate the pressure environment in the real strata. In view of the fact that the pressure of different strata has a significant impact on the physical and chemical properties of the core, the present invention reproduces this environment, so that the artificial thin-layer core can truly reflect the behavior of the underground strata under different pressures. This is of great significance for the study of oil and gas reservoirs, the evaluation of reservoirs, and the prediction of geological disasters. The present invention has the advantages of simple structure, high precision, and low energy consumption. It not only realizes the preparation of millimeter-level ultra-thin cores, but also can quantify the crossflow characterization method between thin-layer reservoirs by simulating parameters such as core permeability; it helps to better control the structure and physical properties of thin-layer cores, and has important guiding significance for oil field exploitation and subsequent process and construction parameter optimization.

[0039] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A thin layer core preparation device, characterized by: The invention comprises a mold for making a core with a thin and differential layer, a core profile plate for making a core with a thin and differential layer, and a hydraulic press. The core mould for making a core with a thin and differential layer is arranged in a constant temperature heater, the inner cavity of the core mould for making a core with a thin and differential layer can accommodate the cut core slices, and the core profile plate for making a core with a thin and differential layer is arranged just above the opening of the core mould for making a core with a thin and differential layer; a temperature and pressure controller for controlling the temperature and pressure in the core mould for making a core with a thin and differential layer is arranged in the hydraulic press, and an atomizing spraying assembly is arranged in the hydraulic press for atomizing a curing agent and spraying it into the core slices in the core mould for making a core with a thin and differential layer; The constant temperature heater is arranged in the base, and the hydraulic press is arranged on the top of the base.

2. A thin layer core preparation device according to claim 1, characterized in that: The atomizing spray assembly comprises an atomizer and an atomizing spray head. The atomizer is arranged at the top of the hydraulic press, the atomizing spray head is arranged at the bottom of the hydraulic press, the outlet of the atomizer is connected to the atomizing spray head through a pipeline; the upper end of the atomizer is connected to the height adjustment frame.

3. The thin layer core preparation device according to claim 1, characterized in that: The invention also comprises a drying box. After the core in the thin-layer core making mold is pressurized and formed, it is taken out and placed in the drying box for solidification.

4. The thin layer core preparation device according to claim 1, characterized in that: The core slices are cut from core raw materials by a core cutting machine. The core raw materials include quartz sand with different mesh sizes and a binder. The quartz sand with different mesh sizes is beaten and stirred with the binder by a double hammer stirrer for 30 to 50 minutes to obtain a variety of homogenized core raw materials corresponding to the mesh sizes of the quartz sand.

5. A thin layer core preparation device according to claim 4, characterized in that: The mesh sizes of the quartz sand are 10-20 meshes, 20-40 meshes, 40-60 meshes, 60-100 meshes, 100-200 meshes and above 200 meshes, respectively; the binder includes epoxy resin and polyester.

6. A thin layer core preparation device according to claim 4, characterized in that: The double-hammer mixer comprises a stirring frame, a control panel, a stirring double hammer and a raw material tank, wherein the raw material tank is used to contain quartz sand and a binder, the upper ends of the stirring double hammers are connected to the control panel, the control panel is connected to the stirring frame, and the control panel controls the stirring double hammers to beat and stir the quartz sand and the binder in the raw material tank; the material of the stirring double hammers is rubber.

7. The thin layer core preparation device according to claim 4, characterized in that: The core cutting machine comprises a screw pressurizing device and a cutting knife. The homogenized core raw material is put into a mold of the screw pressurizing device, and the core raw material is pressed into the shape of the mold by rotating the pressurizing rod. A scale and a height adjustment button are provided on the outer wall of the screw pressurizing device. The cutting knife is arranged on the opposite side of the scale. The cutting knife is connected to the height adjustment button, and the height of the cutting knife is adjusted by the height adjustment button. A conveyor belt is provided at the bottom of the scale, and the conveyor belt is used to transport the cut core slices out.

8. A method for preparing a thin layer core, characterized in that: The method of preparing a thin-layer core by using the thin-layer core preparation device according to any one of claims 1 to 7 comprises the following steps: Preparation of core slices: Preparing several core slices of the same shape and the same or different thicknesses; Preheating and atomization: Start the constant temperature heater to preheat the core slices in the thin layer core making mold, and start the atomization spray component to pre-atomize the curing agent; Pressurizing and spraying curing agent: put the first layer of core slices into the mold for making thin and poor layer cores, and use a hydraulic press to simulate the formation pressure to pressurize the first layer of core slices for 5-50 minutes and then release the pressure; then spray the curing agent on the surface of the first layer of core slices through the atomizing spray component; Placing the second layer of core slices on the first layer of core slices, and repeating the above steps of pressurizing and spraying the curing agent; Each time a layer of core slices is placed, the above-mentioned pressurization and spraying of curing agent need to be repeated until the core slices are stacked and pressed into the required thin layer core; After the thin and poor layer core is pressed, the pressurization is stopped, and the thin and poor layer core is taken out and put into the oven for curing.

9. A method for preparing a thin and poorly layered core according to claim 8, characterized in that: Conduct permeability tests on solidified thin-layer cores to quantify crossflow between thin-layer reservoirs; Under the physical property conditions of simulating natural thin and poor formations, the influence rules of core permeability corresponding to different quartz sand mesh numbers are as follows: y = -0.0004x 3 + 0.1966x 2 - 30.843x + 1532.5 Where: y—permeability, 10 -3 , um 2 ; x—quartz sand mesh number, mesh.

10. A method for preparing a thin layer core according to claim 8, characterized in that: The preparation process of the core slice is as follows: Prepare quartz sand and binder of different mesh sizes, sieve the quartz sand and inject it into the raw material tank with the binder, start the double hammer agitator, beat and stir to obtain a variety of homogenized core materials corresponding to the mesh sizes of the quartz sand; The homogenized core material is placed in a core cutting machine, and the core materials with different permeabilities are cut into core slices with the same shape and the same or different thicknesses.

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