Thin and poor layer core preparation device and preparation method

Abstract

The present invention discloses a preparation device and a preparation method for a thin and poor layer core, belonging to the technical field of core preparation. The preparation device includes a thin and poor layer core production mold, a thin and poor layer core pressing plate, and a hydraulic press. The cut core thin slices are placed in the thin and poor layer core production mold placed in a constant temperature heater, and the hydraulic press presses the core thin slices through the thin and poor layer core pressing plate. The curing agent is atomized and sprayed onto the core thin slices through an atomizing spraying assembly; the preparation method includes: preparing core thin slices, atomizing the curing agent, applying pressure, and spraying the curing agent; each time a layer of core thin slices is placed, the steps of applying pressure and spraying the curing agent are repeated until the core thin slices are stacked and pressed into a thin and poor layer core; finally, the thin and poor layer core is taken out and placed in an oven for curing. The hydraulic press is used to simulate the pressure environment of the real formation, and at the same time ensure that each layer of core thin slices can be evenly sprayed with the curing agent; the core permeability of the prepared thin and poor layer core is tested, and the crossflow between thin and poor reservoirs is quantified.

Description

Technical Field

[0001] The present invention belongs to the technical field of core preparation, and particularly relates to a thin and poor layer core preparation device and a preparation method. Background Art

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

[0003] However, the preparation of thin and poor layer cores still faces many challenges. Different from the preparation of conventional cores, thin and poor rock layers often have complex layered structures, and there are significant differences in lithology, porosity, permeability, etc. between layers. The preparation of thin and poor layer cores can simulate this geological structure with thin layer changes and provide an experimental platform for oilfield experts to study the interface transition between rock layers, interlayer differences, and physical property changes of different lithologic layers. This is of great significance for reservoir evaluation in oil and gas exploration.

[0004] In the process of preparing thin and poor layer cores, a common method is to use existing cores and bond different types of rocks into a multi-layer structure through adhesives. However, this method has some drawbacks. First, the cores made by the conventional stacking method are prone to unstable structures under high displacement pressure differences and are difficult to reproduce the relationship of the real pore throat structure. In addition, it is also difficult to produce ultra-thin core slices by conventional methods, 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 thin and poor layer core preparation method has certain limitations when meeting the requirements of complex reservoir structures. It is particularly necessary to carry out research on thin and poor layer core preparation technology. Summary of the Invention

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

[0006] To solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0007] A preparation device for thin and poor layer cores, comprising a thin and poor layer core production mold, a thin and poor layer core pressing plate, and a hydraulic press. The thin and poor layer core production mold is arranged in a constant temperature heater, and the inner cavity of the thin and poor layer core production mold can accommodate the cut core slices. The thin and poor layer core pressing plate is arranged directly above the opening of the thin and poor layer core production mold; a temperature and pressure controller for controlling the temperature and pressure in the thin and poor layer core production mold is arranged in the hydraulic press, and an atomizing spraying assembly is arranged in the hydraulic press for atomizing and spraying a curing agent into the core slices in the thin and poor layer core production mold; the constant temperature heater is arranged in a base, and the hydraulic press is arranged on the top of the base.

[0008] Preferably, the atomizing spraying assembly includes an atomizer and an atomizing spray head. The atomizer is arranged on the top of the hydraulic press, the atomizing spray head is arranged on the bottom of the hydraulic press, and the outlet of the atomizer is connected to the atomizing spray head through a pipeline; the upper end of the atomizer is connected to a height adjustment frame.

[0009] Preferably, it further includes a drying oven. After the core in the thin and poor layer core production mold is pressed and formed, it is taken out and placed in the drying oven for curing.

[0010] Preferably, the core slices are cut from core raw materials by a core cutting machine. The core raw materials include quartz sands of different mesh numbers and a binder. The quartz sands of different mesh numbers and the binder are respectively beaten and stirred by a double-hammer stirrer for 30 to 50 minutes to obtain a variety of homogenized core raw materials corresponding to the mesh numbers of the quartz sands.

[0011] Preferably, the mesh numbers of the quartz sands are respectively 10 - 20 mesh, 20 - 40 mesh, 40 - 60 mesh, 60 - 100 mesh, 100 - 200 mesh, and above 200 mesh, and the binder includes epoxy resin and polyester.

[0012] Preferably, the double-hammer stirrer includes a stirring frame, a control panel, stirring double hammers, and a raw material tank. The raw material tank is used to accommodate the quartz sand and the 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.

[0013] Preferably, the core cutting machine includes a spiral pressurizer and a cutting knife. The homogenized core raw materials are put into the mold of the spiral pressurizer, and the core raw materials are pressed into the shape of the mold by rotating the pressure rod; a scale and a height adjustment knob are arranged on the outer wall of the spiral pressurizer, the cutting knife is arranged on the opposite side of the scale, and the cutting knife is connected to the height adjustment knob, and the height of the cutting knife is adjusted by the height adjustment knob; a conveyor belt is arranged at the bottom of the scale, and the conveyor belt is used to convey the cut core slices out.

[0014] The present invention also provides a method for preparing a thin and poor layer core, which uses the above-mentioned thin and poor layer core preparation device to prepare a thin and poor layer core, and includes the following steps:

[0015] Preparing core thin sections: Prepare several core thin sections with the same or different shapes and thicknesses in advance;

[0016] Preheating and atomizing in advance: Start the constant temperature heater to preheat the core thin sections in the thin and poor layer core production mold, and at the same time start the atomizing spraying component to pre-atomize the curing agent;

[0017] Pressurizing and spraying the curing agent: Place the first layer of core thin sections into the thin and poor layer core production mold, and the hydraulic press simulates the formation pressure to pressurize the first layer of core thin sections for 5 - 50 minutes and then relieve the pressure; then spray the curing agent onto the surface of the first layer of core thin sections through the atomizing spraying component;

[0018] Place the second layer of core thin sections on the first layer of core thin sections, and repeat the above steps of pressurizing and spraying the curing agent;

[0019] For each layer of core thin sections placed, the above steps of pressurizing and spraying the curing agent need to be repeated until the core thin sections are stacked and pressed into the required thin and poor layer core;

[0020] After the thin and poor layer core pressing is completed, stop pressurizing, take out the thin and poor layer core and put it into the oven for curing.

[0021] Preferably, perform permeability testing on the cured thin and poor layer core to quantify the crossflow between thin and poor reservoirs;

[0022] Under the physical property conditions simulating the natural thin and poor formation, the influence law of core permeability corresponding to different mesh numbers of quartz sand is as follows:

[0023] y = -0.0004x 3 + 0.1966x 2 - 30.843x + 1532.5

[0024] In the formula: y - permeability, 10 -3 , um 2 ;

[0025] x - mesh number of quartz sand, mesh.

[0026] Preferably, the preparation process of the core thin sections is as follows:

[0027] Prepare quartz sand with different mesh numbers and a cementing agent, sieve the quartz sand and inject it into the raw material tank together with the cementing agent, start the double-hammer stirrer, and beat and stir to obtain a variety of homogenized core raw materials corresponding to the mesh numbers of quartz sand;

[0028] Put the homogenized core raw materials into the core cutting machine, and cut the core raw materials with different permeabilities into core thin slices with the same shape and the same or different thicknesses.

[0029] Compared with the prior art, the beneficial effects produced by the present invention are as follows:

[0030] The present invention ensures the temperature required for the preparation of the thin and poor layer cores through a constant temperature heater, and uses a hydraulic press to pressurize the core thin slices in the mold for making the thin and poor layer cores, so as to simulate the pressure environment in the real formation; the curing agent is atomized by the atomizing spraying assembly and sprayed into the mold for making the thin and poor layer cores, ensuring that each layer of core thin slices can be evenly sprayed with the curing agent; the pressed and formed thin and poor layer cores are taken out, dried and cured, and the core permeability is tested through experiments, realizing the quantification of the method for characterizing the crossflow between thin and poor reservoirs. The present invention has the advantages of simple structure, high precision and less energy consumption. It not only realizes the preparation of millimeter-level ultra-thin layer cores, but also can realize the quantification of the method for characterizing the crossflow between thin and poor reservoirs through the simulation of parameters such as core permeability; it helps to better control the structure and physical properties of the thin and poor layer cores, and has important guiding significance for optimizing the oilfield exploitation and subsequent process and construction parameters. Description of the Drawings

[0031] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention.

[0032] In the drawings:

[0033] Figure 1 is a schematic structural diagram of a device for preparing thin and poor layer cores provided by an embodiment of the present invention;

[0034] Figure 2 is a schematic structural diagram of a double-hammer stirrer in an embodiment of the present invention;

[0035] Figure 3 is a schematic structural diagram of a core cutting machine in an embodiment of the present invention;

[0036] Figure 4 is a corresponding relationship diagram between the mesh number of quartz sand and the core permeability;

[0037] In the figure:

[0038] 1 - Mold for making thin and poor layer cores; 2 - Pressing plate for thin and poor layer cores; 3 - Hydraulic press; 4 - Constant temperature heater; 5 - Temperature and pressure controller; 6 - Base; 7 - Atomizer; 8 - Atomizing spraying head; 9 - Height adjusting frame; 10 - Stirring frame; 11 - Control panel; 12 - Stirring double hammers; 13 - Raw material tank; 14 - Screw pressurizer; 15 - Cutting knife; 16 - Scale; 17 - Height adjusting knob; 18 - Conveyor belt; 19 - Display. Detailed implementation manners

[0039] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clear and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In the following detailed description of the present invention, some specific details are described in detail. However, those skilled in the art can also fully understand the present invention for the parts not described in detail.

[0040] In addition, those of ordinary skill in the art should understand that the provided drawings are only for illustrating the purpose, features and advantages of the present invention, and the drawings are not actually drawn to scale.

[0041] At the same time, unless the context clearly requires otherwise, the words such as "including", "comprising" and the like in the whole specification and claims should be interpreted as the meaning of including rather than exclusive or exhaustive meaning; that is, the meaning of "including but not limited to".

[0042] As Figure 1 shown, a preparation device for thin difference layer cores includes a thin difference layer core production mold 1, a thin difference layer core pressing plate 2 and a hydraulic press 3. The thin difference layer core production mold 1 is arranged in a constant temperature heater 4. The inner cavity of the thin difference layer core production mold 1 can accommodate the cut core slices. The thin difference layer core pressing plate 2 is arranged directly above the opening of the thin difference layer core production mold 1. A temperature and pressure controller 5 for controlling the temperature and pressure in the thin difference layer core production mold is arranged in the hydraulic press 3. An atomizing spraying assembly is arranged in the hydraulic press 3 for atomizing and spraying a curing agent onto the core slices in the thin difference layer core production 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. Among them, the atomizing spraying assembly includes an atomizer 7 and an atomizing spray head 8. The atomizer 7 is arranged on the top of the hydraulic press 3, and the atomizing spray head 8 is arranged on 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 a height adjusting frame 9. The cut core slices are put into the thin difference layer core production mold, preheated by the 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 core slices, and then the core slices are placed again and pressurized to bond and fix them together.

[0043] In the specific design, the thin and poor layer core pressing plate is connected to the screen monitor, and through the display 19, the temperature and pressure conditions inside the thin and poor layer core manufacturing mold during the process of the hydraulic press pressing the core slices can be monitored and controlled in real time. At the same time, a container for containing the curing agent is arranged at the inlet of the atomizer 7. 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 and poor layer core manufacturing mold 1 through the atomizing spray head 8. The temperature and pressure controller 5 continuously transmits electrical signals to the hydraulic press, and the real-time temperature and pressure conditions are obtained through the sensor.

[0044] During the specific production, it also includes a drying oven (not shown in the figure). After the thin and poor layer core in the thin and poor layer core manufacturing mold is press-formed, it is taken out and placed in the drying oven for curing.

[0045] Among them, the core slice is cut from the core raw material by a core cutting machine. The core raw material includes quartz sands with different mesh numbers and a binder. The quartz sands with different mesh numbers and the binder are respectively beaten and stirred by a double-hammer stirrer for 30 to 50 minutes to obtain a variety of homogenized core raw materials corresponding to the mesh numbers of the quartz sands. Among them, the mesh numbers of the quartz sands are respectively 10 to 20 meshes, 20 to 40 meshes, 40 to 60 meshes, 60 to 100 meshes, 100 to 200 meshes, and more than 200 meshes, and the binder includes epoxy resin and polyester. Using quartz sand and binder to prepare the core is the prior art, and the specific ratio is not within the protection scope of the present invention and will not be elaborated here. It is determined according to the prepared core situation and is proportioned according to the physical properties of the simulated formation. Each core is different. For example, a core with a permeability of 200 mD is required to be prepared according to the ratio of 40 to 60 mesh quartz sand: binder of 9:1.

[0046] In the specific embodiment of the present invention, as Figure 2 shown, the double-hammer stirrer includes a stirring frame 10, a control panel 11, stirring double hammers 12, and a raw material tank 13. The raw material tank 13 is used to accommodate quartz sand and binder. The upper ends of the stirring double hammers 12 are connected to the control panel 11. The control panel 11 is connected to the stirring frame 10. The control panel 11 controls the stirring double hammers 12 to beat and stir the quartz sand and binder in the raw material tank 13. The stirring double hammers are detachably connected. The material of the stirring double hammers 12 is rubber, and the raw material tank 13 is made of steel. During application, the specified mesh number of quartz sand and the required binder are injected into the raw material tank. The control panel is used to control the stirring double hammers to switch the functions of stirring and hammering to homogenize the quartz sand and binder in the raw material tank.

[0047] In the specific design, the top of the stirring double hammers is connected to the lifting rod of the lifting component. The lifting action of the stirring double hammers at the lower end of the lifting component is controlled through the control panel to repeatedly hammer 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 are controlled through the control panel to realize the rotation of the stirring double hammers. Among them, the lifting component can adopt a cylinder, a hydraulic cylinder or an electric push rod, etc., as long as it can realize the up and down lifting of the stirring double hammers. A plurality of small knives are radially arranged on the outer surface of the stirring double hammers. During the rotation of the stirring double hammers, the highly viscous core raw materials are cut by the plurality of small knives, so as to realize the homogenization treatment of the quartz sand and the binder.

[0048] In a specific embodiment of the present invention, as Figure 3 shown, the core cutting machine includes a screw press 14 and a cutting knife 15. The homogenized core raw materials are put into the mold of the screw press 14, and the core raw materials are pressed into the mold shape by rotating the pressing rod; a scale 16 and a height adjustment knob 17 are arranged on the outer wall of the screw press 14. The cutting knife 15 is arranged on the opposite side of the scale 16, and the cutting knife 15 is connected to the height adjustment knob 17. The height of the cutting knife 15 is adjusted through the height adjustment knob 17; a conveyor belt 18 is arranged at the bottom of the scale 16, and the conveyor belt 18 is used to convey the cut core thin slices out. The cutting knife adopts a diamond core cutting knife and is horizontally installed, and can cut the core raw materials extruded from the bottom of the mold into core thin slices. The homogenized core raw materials are put into the core cutting machine, and the core raw materials with different permeabilities are respectively cut into core thin slices with the same shape and the same or different thicknesses; the height of the cutting knife 15 is accurately controlled by using the scale 16.

[0049] In the specific production, the screw press 14 includes a tubular mold, a T-shaped pressing rod and a template at its bottom. A plug cover is arranged at the top of the mold, and the pressing rod is in threaded cooperation with the plug cover; the height adjustment knob 17 is coaxially fixed with the internal gear, the gear meshes with the internal rack, and the cutting knife 15 is fixed at the lower end of the rack. By rotating the height adjustment knob 17, the rack is driven to lift, so as to adjust the height of the cutting knife 15. At the same time, the cutting knife 15 is connected to a hydraulic rod, and the cutting knife 15 is driven to move horizontally along the hydraulic rod, so as to cut the bottom of the core raw materials into core thin slices. During application, after adjusting the height of the cutting knife by using the height adjustment knob, rotate the pressing rod to make it move downward, and use the template to extrude the core raw materials, so that the core raw materials are successively extruded from the bottom of the mold; the hydraulic rod is used to drive the cutting knife to stretch and retract, and the core raw materials are successively cut from bottom to top.

[0050] The present invention also provides a method for preparing a thin and poor layer core, using the above-mentioned thin and poor layer core preparation device to prepare a thin and poor layer core, including the following steps:

[0051] (1) Preparation of core thin sections: Prepare several core thin sections with the same or different shapes and thicknesses in advance. The specific thickness can be adjusted according to the test requirements. The preparation process of the core thin sections is as follows:

[0052] Prepare quartz sands with different mesh numbers and a binder. After sieving the quartz sands, inject them into the raw material tank 13 together with the binder. Start the double-hammer stirrer and beat and stir to obtain a variety of homogenized core raw materials corresponding to the mesh numbers of the quartz sands.

[0053] Put the homogenized core raw materials into the core cutting machine and cut the core raw materials with different permeabilities into core thin sections with the same shape and the same or different thicknesses.

[0054] (2) Preheating and atomization in advance: Start the constant-temperature heater 4 to preheat the core thin sections in the thin and poor layer core production mold 1, and at the same time start the atomizer 7 to atomize the curing agent in advance.

[0055] (3) Pressurization and spraying of the curing agent: Put the first layer of core thin sections into the thin and poor layer core production mold 1. The hydraulic press 3 simulates the formation pressure (0 - 50 MPa) to pressurize the first layer of core thin sections for 5 - 50 minutes and then release the pressure. Then, spray the atomized curing agent onto the surface of the first layer of core thin sections 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; a visualization interface for data such as the force on the core thin sections and temperature changes will be provided on the display 19, and real-time adjustment will be made to ensure that the environment during the entire experiment is consistent with the actual formation conditions.

[0056] Place the second layer of core thin sections on the first layer of core thin sections and repeat the above steps of pressurization and spraying of the curing agent;

[0057] For each layer of core thin sections placed, the above steps of pressurization and spraying of the curing agent need to be repeated until the core thin sections are stacked and pressed into the required thin and poor layer core;

[0058] After the thin and poor layer core is pressed, stop pressurization, take out the thin and poor layer core and put it into the oven for curing.

[0059] By observing and testing the cured thin and poor layer core thin sections, the changes in their physical properties can be analyzed.

[0060] After the experiment, turn off the power switches of all equipment.

[0061] The thickness and permeability of the core thin layer are defined as follows. This value depends on the thickness of the small layer core thin sections in the simulated natural thin and poor formation and the underground natural pressure conditions. The corresponding permeabilities of the small layer core thin sections after simulation are also different. The simulation data is shown in the following table:

[0062]

[0063] The thickness Ai and permeability Ki of the core thin sections in this table are the core data of the simulated formation, which are filled in by the experimenters.

[0064] Under the simulated formation pressure conditions, multiple physical property experiments were carried out. The permeability of the solidified thin and poor layer cores was tested, the crossflow between the thin and poor reservoirs was quantified, and the influence law of the core permeability corresponding to different mesh numbers of quartz sand was obtained, as Figure 4 shown. The influence law of the core permeability corresponding to different mesh numbers of quartz sand is as follows:

[0065] y = -0.0004x 3 + 0.1966x 2 - 30.843x + 1532.5

[0066] In the formula: y—permeability, 10 -3 , um 2 ;

[0067] x—mesh number of quartz sand, mesh.

[0068] To sum up, the present invention ensures the temperature required for the preparation of the thin and poor layer cores through a constant temperature heater, and uses a hydraulic press to pressurize the core thin sections in the mold for the thin and poor layer cores, so as to simulate the pressure environment in the real formation. In view of the fact that the pressure of different formations has a significant impact on the physical and chemical properties of the cores, and the present invention reproduces this environment, enabling the artificial thin and poor layer cores to truly reflect the behavior of underground rock formations under different pressures. This is of great significance for the research 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 less energy consumption. It not only realizes the preparation of millimeter-scale ultra-thin layer cores, but also can quantify the characterization method of crossflow between thin and poor reservoirs through the simulation of parameters such as core permeability; it helps to better control the structure and physical properties of the thin and poor layer cores, and has important guiding significance for the optimization of oilfield exploitation and subsequent process and construction parameters.

[0069] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A preparation method for a thin and poor layer core, characterized in that Prepare a thin and poor layer core using a thin and poor layer core preparation device, including the following steps: Prepare core thin sections: Prepare several core thin sections with the same shape and the same or different thicknesses in advance; Preheat and atomize in advance: Start the constant temperature heater to preheat the core thin sections in the thin and poor layer core production mold, and at the same time start the atomizing spraying component to atomize the curing agent in advance; Pressurize and spray the curing agent: Place the first layer of core thin sections into the thin and poor layer core production mold, and the hydraulic press simulates the formation pressure to pressurize the first layer of core thin sections for 5 - 50 minutes and then relieve the pressure; then spray the curing agent onto the surface of the first layer of core thin sections through the atomizing spraying component; Place the second layer of core thin sections on the first layer of core thin sections, and repeat the above steps of pressurizing and spraying the curing agent; For each layer of core thin sections placed, the above steps of pressurizing and spraying the curing agent need to be repeated until the core thin sections are stacked and pressed into the required thin and poor layer core; After the thin and poor layer core pressing is completed, stop pressurizing, take out the thin and poor layer core and put it into the oven for curing; Perform permeability tests on the cured thin and poor layer core to quantify the crossflow between thin and poor reservoirs; Under the physical property conditions simulating natural thin and poor formations, the influence law of core permeability corresponding to different mesh numbers of quartz sand is as follows: y = -0.0004x 3 + 0.1966x 2 - 30.843x + 1532.5 Where: y - permeability, 10 -3 μm 2 ; x - mesh number of quartz sand, mesh; The thin and poor layer core preparation device includes a thin and poor layer core production mold, a thin and poor layer core pressing plate, and a hydraulic press. The thin and poor layer core production mold is arranged in the constant temperature heater. The inner cavity of the thin and poor layer core production mold can accommodate the cut core thin sections. The thin and poor layer core pressing plate is arranged directly above the opening of the thin and poor layer core production mold; a temperature and pressure controller for controlling the temperature and pressure in the thin and poor layer core production mold is arranged in the hydraulic press. An atomizing spraying component is arranged in the hydraulic press for atomizing and spraying the curing agent into the core thin sections in the thin and poor layer core production mold; the constant temperature heater is arranged in the base, and the hydraulic press is arranged on the top of the base.

2. The method for preparing a thin-difference layer core according to claim 1, characterized in that: The preparation process of the core thin sections is as follows: Prepare quartz sand with different mesh numbers and a cementing agent. After sieving the quartz sand, inject it into the raw material tank together with the cementing agent, and start the double - hammer stirrer to beat and stir to obtain a variety of homogenized core raw materials corresponding to the mesh numbers of quartz sand; Put the homogenized core raw materials into the core cutting machine, and cut the core raw materials with different permeabilities into core thin sections with the same shape and the same or different thicknesses.

3. A method for preparing a thin-difference layer core according to claim 1, characterized in that: The atomizing spraying component includes an atomizer and an atomizing spraying head. The atomizer is arranged on the top of the hydraulic press, the atomizing spraying head is arranged on the bottom of the hydraulic press, and the outlet of the atomizer is connected to the atomizing spraying head through a pipeline; the upper end of the atomizer is connected to the height - adjusting frame.

4. A method for preparing a thin-difference layer core according to claim 1, characterized in that: It also includes a drying oven. After the core in the thin and poor layer core production mold is pressurized and formed, it is taken out and placed in the drying oven for curing.

5. A method for preparing a thin-layer difference core according to claim 1, characterized in that: The core thin sections are cut from core raw materials by a core cutting machine. The core raw materials include quartz sand with different mesh numbers and a cementing agent. The quartz sand with different mesh numbers and the cementing agent are respectively beaten and stirred by a double - hammer stirrer for 30 - 50 minutes to obtain a variety of homogenized core raw materials corresponding to the mesh numbers of quartz sand.

6. A method for preparing a thin-difference layer core according to claim 5, characterized in that: The mesh sizes of the quartz sand are respectively 10 - 20 mesh, 20 - 40 mesh, 40 - 60 mesh, 60 - 100 mesh, 100 - 200 mesh, and above 200 mesh, and the binder is epoxy resin and polyester.

7. A method for preparing a thin differential layer core according to claim 5, characterized in that: The double - hammer stirrer includes a stirring frame, a control panel, stirring double hammers, and a raw material tank. The raw material tank is used to hold the quartz sand and the 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 pound and stir the quartz sand and the binder in the raw material tank; the material of the stirring double hammers is rubber.

8. A method for preparing a thin-difference layer core according to claim 5, characterized in that: The core cutter includes a screw press and a cutting knife. The homogenized core raw material is put into the mold of the screw press, and the core raw material is pressed into the shape of the mold by rotating the pressure rod; a scale and a height adjustment knob are provided on the outer wall of the screw press, the cutting knife is arranged on the opposite side of the scale, the cutting knife is connected to the height adjustment knob, and the height of the cutting knife is adjusted by the height adjustment knob; a conveyor belt is provided at the bottom of the scale, and the conveyor belt is used to convey the cut core slices out.

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