Multifunctional overburden pressure static imbibition experimental device and use method thereof

Abstract

The invention discloses a multifunctional overburden pressure static imbibition experiment device which comprises an imbibition main body and a control system, the imbibition main body is connected with a pressurizing device through a fluid pipeline, and the control system is connected with the imbibition main body and the pressurizing device through wires. The invention further discloses a using method of the multifunctional overburden pressure static imbibition experimental device. The using method comprises the following steps that the rock core saturated oil volume of an experimental rock core is calculated; adjusting and assembling the multifunctional overburden pressure static imbibition experimental device, and putting the experimental rock core into the annular gland; imbibition liquid is added into the imbibition barrel; starting a test, and regularly recording experimental data; closing the heating jacket and the pressurizing device, and taking out the experimental rock core to finish the experiment. A multifunctional overburden pressure static imbibition experimental device is suitable for experiments of conventional rock cores or rock cores with different fracture shapes and lengths, and is flexible to use, wide in application and convenient to mount, maintain and dismount.

Description

Technical Field

[0001] The invention belongs to the technical field of imbibition oil production, relates to a multifunctional pressure-covered static imbibition experimental device, and also relates to a use method of the multifunctional pressure-covered static imbibition experimental device. Background Art

[0002] With the increase in energy demand and the development of oil and gas development technology, low permeability reservoirs have become an important part of my country's oil and gas resources. Due to the "three lows and two highs" characteristics of low permeability, low porosity, low pressure, high capillary pressure and high effective stress, the development of such reservoirs is extremely difficult. At the same time, microcracks are developed in low permeability reservoirs, and large-scale volume fracturing measures are usually used to increase production capacity, making the network system formed by pores, microcracks and artificial cracks more complex. At the same time, the seepage capacity between fractures and matrix is ​​very different, and injected water is very easy to channel along the fractures, resulting in a large amount of residual oil enriched in the matrix, and the water injection development effect is poor. How to effectively play the imbibition effect between fractures and matrix and improve the utilization of crude oil in the matrix has become an important issue to improve the development effect of low permeability reservoirs.

[0003] Imbibition refers to the multiphase flow process in which the wetting phase fluid spontaneously enters the porous medium under the action of capillary force and replaces the non-wetting phase fluid inside. In order to accurately reflect the effect of spontaneous imbibition on the recovery of low permeability reservoirs, static imbibition experiments are usually carried out indoors. At present, the main method used for imbibition experiments in the laboratory is to use the Amott imbibition bottle. The measurement principle of the imbibition device is to immerse the core saturated with crude oil in the imbibition bottle filled with imbibition liquid. The imbibition liquid will displace the crude oil from the pores of the core. Under the action of buoyancy, the oil droplets float to the graduated tube at the top of the imbibition bottle, and the imbibition recovery rate is obtained according to the degree of the graduated tube. However, static imbibition devices generally have the following problems: the experimental process of oil production in some high-temperature and high-pressure imbibition devices cannot be displayed intuitively; the oil film produced by imbibition is very small, and as the imbibition process proceeds, it is easy to adhere to the rock surface, resulting in the inability to accurately measure the volume of imbibed crude oil; some imbibition devices are restricted by conditions such as the core holder and cannot simulate the imbibition process under different boundary conditions of the core; the overburden pressure of the reservoir has a great influence on the cracks and pores of the reservoir, but most static imbibition experimental devices can only conduct experiments at normal temperature and pressure or at high temperature and high pressure fluid environments, and cannot truly simulate the imbibition process under actual reservoir conditions, resulting in the imbibition results dominated by capillary pressure not being able to truly reflect the actual reservoir imbibition and oil drainage process.

[0004] In response to these problems, some researchers have made some improvements to the imbibition device: a Chinese patent application with publication number CN108918326B and publication date November 30, 2018 discloses a high-temperature and high-pressure core imbibition experimental device and method, but it can only simulate the core imbibition conditions of a high-temperature and high-pressure fluid environment; a Chinese patent application with publication number CN111521542B and publication date August 24, 2021 discloses a tight reservoir core static pressurization visualization imbibition experimental device, which places the core in a fluid that can be applied. The high-pressure fluid pressure is placed in an infiltration bottle with a visualization window, and then the infiltration bottle is placed in a constant temperature box. Although the visualization of infiltration and high-temperature and high-pressure fluid infiltration are achieved, the ring pressure cannot be applied to the core to simulate the pressure of the overlying rock formation. In addition, the infiltration bottle is heated by the constant temperature box, and then the infiltration fluid is heated. The heating process is slow, and it is inconvenient to assemble and disassemble the instrument in the constant temperature box; the Chinese patent application with publication number CN106769769B and publication date February 14, 2020 discloses a rock pressurization infiltration device, which is composed of multiple hydraulic The oil cylinder is connected to the annular claws of the fixed core through the push rod, and the annular claws apply annular pressure to the experimental core, but this device only solves the problem of simulating the overburden pressure of the core. There are still problems such as the imbibition liquid cannot be pressurized and heated, the imbibition oil droplets are easily attached to the imbibition net on the annular claws, the core cannot be visualized during the experiment, the imbibition process under different boundary conditions of the core cannot be simulated, and the instrument structure is complicated. The Chinese patent application with publication number CN115683978A and publication date February 3, 2023 discloses a method for accurately simulating reservoirs and The spontaneous imbibition experimental measurement device under field development conditions can apply radial confining pressure to the core, but there is still no pressure load in the axial direction, and it can only partially simulate the geostress conditions of the reservoir. At the same time, the core imbibition is an axial one-dimensional imbibition process; the Chinese patent application with publication number CN212410387U and publication time of January 26, 2021 discloses a kind of imbibition experimental device simulating formation pressure conditions, but it also has the problem of only being able to apply radial confining pressure to realize an axial one-dimensional imbibition process, and cannot simulate the imbibition process of the core under different boundary conditions.

[0005] In summary, the existing technology has problems such as the infiltration process of high temperature and high pressure cannot be displayed intuitively, the oil film attached to the surface of the core is difficult to peel off, the infiltration process of the core under different boundary conditions is difficult to simulate, and the experimental process cannot truly simulate the reservoir conditions, which makes the method of static infiltration experiment single and has large errors. Summary of the invention

[0006] The purpose of the present invention is to provide a multifunctional static imbibition experimental device under covering pressure, which solves the problems in the prior art that the high temperature and high pressure imbibition process cannot be displayed intuitively, the oil film attached to the core surface is difficult to peel off, the imbibition process under different boundary conditions of the core is difficult to simulate, and the experimental process cannot truly simulate reservoir conditions.

[0007] Another object of the present invention is to provide a method for using the multifunctional pressure-covering static infiltration experimental device.

[0008] The technical solution adopted by the present invention is a multifunctional static infiltration experimental device with covering pressure, which includes an infiltration body and a control system. The infiltration body is connected to a pressurizing device through a fluid pipeline, and the control system is respectively connected to the infiltration body and the pressurizing device through wires; the infiltration body includes a base, an infiltration cylinder is arranged on the base, and the two ends of the infiltration cylinder are respectively connected to an upper sealing cover and a lower sealing cover, the lower sealing cover is arranged in contact with the base at a side away from the infiltration cylinder, automatic hydraulic presses are respectively arranged on the opposite sides of the infiltration cylinder and on a side of the lower sealing cover away from the infiltration cylinder, and a metering device is arranged on the side of the upper sealing cover away from the infiltration cylinder; an experimental core is arranged in the infiltration cylinder.

[0009] The present invention is also characterized in that: The automatic hydraulic press is sealed and connected to the outer walls on the opposite sides of the absorption cylinder and the outer wall on the side of the lower sealing cover away from the absorption cylinder through screws, and the automatic hydraulic presses on the outer walls on the opposite sides of the absorption cylinder are symmetrically distributed with the axis of the absorption cylinder as the center; the automatic hydraulic press on the side of the lower sealing cover away from the absorption cylinder is arranged on the extension line of the axis of the absorption cylinder; the automatic hydraulic presses on the opposite sides of the absorption cylinder are connected with annular pressure caps through push rods, and the automatic hydraulic press on the side of the lower sealing cover away from the absorption cylinder is connected with a circular pressure cap through a push rod; the annular pressure cap and the circular pressure cap are arranged inside the absorption cylinder.

[0010] The ends of the annular pressure cover are respectively fitted with the circular pressure cover, the circular pressure cover at one end of the annular pressure cover is connected to the upper sealing cover, an ultrasonic vibrator is arranged between the circular pressure cover at the other end of the annular pressure cover and the lower sealing cover, the inner wall of the annular pressure cover is fitted with the experimental core, and the experimental core is fitted with the circular pressure cover; visualization windows are relatively arranged on the outer walls on opposite sides of the imbibition cylinder body, a heating sleeve is fitted on the outer wall of the imbibition cylinder body, an insulation sleeve is fitted on the outer wall of the heating sleeve, and the two ends of the heating sleeve and the insulation sleeve are respectively fitted with the upper sealing cover and the lower sealing cover.

[0011] A pressure gauge is arranged on the fluid pipeline; sealing rings are respectively arranged between the absorption cylinder body and the upper sealing cover and the lower sealing cover; the control system comprises a control box, which is connected to a computer for communication, and is respectively connected to an automatic hydraulic press, an ultrasonic vibrator, a heating sleeve and a pressurizing device through wires; the pressurizing device is connected to the inside of the absorption cylinder body after passing through the lower sealing cover through the fluid pipeline; the metering device comprises a graduated glass tube, which is covered with a protective cover, one end of the protective cover is embedded in the upper sealing cover, and an exhaust valve is arranged on the outer wall of the other end.

[0012] The annular pressure cover includes an infiltration type annular pressure cover, which is composed of two semicircular tubes fitted together, an infiltration pressure net is fitted on the inner wall of the infiltration type annular pressure cover, and a plurality of fluid holes are fitted on the outer wall of the infiltration type annular pressure cover, and the infiltration pressure net is connected with the fluid holes; a rubber sealing gasket is arranged between the fitting surfaces of the two semicircular tubes of the infiltration type annular pressure cover, and the two sides of the rubber sealing gasket are respectively fitted with the infiltration type annular pressure cover; external threaded interfaces are arranged on the outer walls on the opposite sides of the infiltration type annular pressure cover, and the external threaded interfaces are connected with the push rod.

[0013] The annular pressure cover includes a sealed annular pressure cover, which is composed of two semicircular tubes fitted together. A rubber sleeve is fitted on the inner wall of the sealed annular pressure cover, and a rubber sealing gasket is arranged between the two semicircular tube fitting surfaces of the sealed annular pressure cover. Both sides of the rubber sealing gasket are respectively fitted with the sealed annular pressure cover; external threaded interfaces are respectively arranged on the outer walls on the opposite sides of the sealed annular pressure cover, and the external threaded interfaces are respectively connected to the push rods on both sides of the absorption cylinder body.

[0014] The circular pressure cap includes a seepage type circular pressure cap, which includes two threaded columns. The ends of the two threaded columns away from the experimental core are respectively connected to the push rod and the upper sealing cover at the end of the seepage cylinder. A circular pressure plate is fixedly connected to the end of the threaded column close to the experimental core. An annular groove is arranged on the outer wall of the circular pressure plate close to the experimental core. A plurality of seepage holes are opened on the outer wall of the circular pressure plate close to the threaded column, and the seepage holes are connected to the annular grooves.

[0015] The circular pressure cover includes a sealed circular pressure cover, which includes two threaded columns. The two threaded columns are respectively connected to the push rod and the upper sealing cover at the end of the imbibition cylinder at one end away from the experimental core. A circular pressure plate is fixedly connected to the end of the threaded column close to the experimental core. A rubber sealing sheet is fitted on the outer wall of the circular pressure plate close to the experimental core.

[0016] Another technical solution adopted by the present invention is: The method for using the multifunctional pressure-covering static infiltration and absorption experimental device comprises the following steps: S1. Vacuum the experimental core and pressurize it to saturate it with oil. Calculate the saturated oil volume of the experimental core by weighing. ; S2. Adjust and assemble the multifunctional static imbibition test device, and place the test core into the closed area formed by the annular gland and the circular gland, so that the test core fits the annular gland and the circular gland; S3, filling the imbibition cylinder with imbibition liquid and adjusting the experimental pressure; S4, start the experiment and record the experimental data regularly; S5. Turn off the heating jacket and the pressurizing device, take out the experimental core, and the experiment is completed.

[0017] Another technical solution of the present invention is also characterized in that: S2 includes the following steps: adjusting and assembling the multifunctional static imbibition test device, placing the test core on the circular gland, adjusting the automatic hydraulic press on the side of the lower sealing cover away from the imbibition cylinder body so that the two ends of the test core are respectively fitted with the circular gland, and then adjusting the automatic hydraulic presses on the outer walls of the opposite sides of the imbibition cylinder body so that the two sides of the test core are respectively fitted with the annular gland; When adjusting and assembling the multifunctional static imbibition experimental device under pressure, when the imbibition experiment simulates the multi-dimensional imbibition process under pressure, the annular gland uses an imbibition-type annular gland, and the circular gland uses an imbibition-type circular gland; when the imbibition experiment simulates the axial imbibition process under pressure, the annular gland uses a sealed annular gland, and the circular gland uses an imbibition-type circular gland; when the imbibition experiment simulates the radial imbibition process under pressure, the annular gland uses an imbibition-type annular gland, and the circular gland uses a sealed circular gland; S3 includes the following steps: opening the drain valve, adding imbibition liquid into the imbibition cylinder through a pressurizing device, closing the drain valve after the imbibition liquid seeps out of the drain valve, and continuing to add imbibition liquid until the pressure gauge reaches a preset pressure and then stops; S4 includes the following steps: adjusting the temperature of the imbibition liquid in the imbibition cylinder, the pressure of the imbibition liquid in the imbibition cylinder, the axial pressure and radial pressure of the experimental core, starting the test and during the test, using an ultrasonic vibrator to periodically drive away the oil droplets imbibed from the surface of the experimental core, and recording the oil volume produced from the core at that moment. , calculate the core imbibition recovery rate at this time ; Core imbibition recovery The calculation formula is as follows: , in, represents the core recovery rate at time t of the imbibition experiment, represents the core oil production volume at time t in the imbibition experiment, It represents the saturated oil volume of the core in the imbibition experiment.

[0018] The beneficial effects of the present invention are as follows: on the basis of satisfying the visualization of the imbibition experiment, the present invention uses different types of annular pressure caps and circular pressure caps in combination, which not only solves the problem of the core imbibition process under different boundary conditions, but also uses an automatic hydraulic press to connect the annular pressure cap and the circular pressure cap through a push rod, so that the experimental core can simulate the imbibition process under actual reservoir conditions under different overburden pressures; in addition, the temperature, overburden pressure, fluid pressure and ultrasonic vibration frequency of the imbibition experiment are generally controlled by the control box, so that the automation degree and experimental efficiency of the experimental device are higher, resulting in more real and accurate experimental results; at the same time, the imbibition device of the present invention is suitable for conventional cores or cores with different fracture shapes and lengths for experiments, is flexible to use, and has a wide range of uses. In addition, the experimental device of the present invention has a simple structure and is convenient to install, maintain and disassemble. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the multifunctional static infiltration and absorption experimental device of the present invention; Figure 2 It is a structural schematic diagram of the infiltration and absorption main body in the multifunctional pressure-covered static infiltration and absorption experimental device of the present invention; Figure 3 It is a front cross-sectional view of the imbibition body in the multifunctional static imbibition experimental device for covering pressure of the present invention; Figure 4 It is a side cross-sectional view of the imbibition body in the multifunctional static imbibition experimental device under pressure of the present invention; Figure 5 It is a structural schematic diagram of an annular gland in the multifunctional static infiltration and absorption experimental device of the present invention; Figure 6 It is a structural schematic diagram of another annular gland in the multifunctional static infiltration and absorption experimental device of the present invention; Figure 7 It is a structural schematic diagram of a circular gland in the multifunctional static infiltration and absorption experimental device of the present invention; Figure 8 It is a structural schematic diagram of another circular gland in the multifunctional static infiltration and absorption experimental device of the present invention; Fig. 9 This is a multi-dimensional imbibition experiment diagram of the multifunctional static imbibition experiment device according to an embodiment of the present invention; Fig.10 This is an axial imbibition test diagram of the multifunctional static imbibition test device according to an embodiment of the present invention; Fig.11 It is a radial imbibition test diagram of the multifunctional static imbibition test device in an embodiment of the present invention.

[0020] In the figure, 1, the imbibition cylinder; 2-1, the upper sealing cover; 2-2, the lower sealing cover; 3, the push rod; 4, the automatic hydraulic press; 5, the visual window; 6, the annular pressure cover; 6-1, the fluid hole; 6-2, the imbibition net; 6-3, the rubber sleeve; 6-4, the rubber sealing gasket; 6-5, the external thread interface; 7, the circular pressure cover; 7-1, the seepage hole; 7-2, the annular groove; 7-3, the rubber sealing sheet; 7-4, the external thread; 8, the experimental core; 9, the ultrasonic vibrator; 10, the fluid pipeline; 10-1, the pressure gauge; 11, the metering device; 11-1, the protective cover; 12, the drain valve; 13, the heating cover; 14, the insulation cover; 15, the sealing ring; 16, the screw; 17, the wire; 18, the base; 19, the pressurizing device; 20, the control box; 21, the computer. DETAILED DESCRIPTION

[0021] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Multifunctional static infiltration test device, such as Figure 1 As shown, it includes an imbibition body and a control system. The imbibition body is connected to a pressurizing device 19 through a fluid pipeline 10, and the control system is connected to the imbibition body and the pressurizing device 19 through a wire 17 respectively; Figure 2 As shown, the imbibition body includes a base 18, on which an imbibition cylinder body 1 is arranged, and the two ends of the imbibition cylinder body 1 are respectively connected with an upper sealing cover 2-1 and a lower sealing cover 2-2, the lower sealing cover 2-2 is arranged in close contact with the base 18 on the side away from the imbibition cylinder body 1, automatic hydraulic presses 4 are respectively arranged on the opposite sides of the imbibition cylinder body 1 and on the side of the lower sealing cover 2-2 away from the imbibition cylinder body 1, and a metering device 11 is arranged on the side of the upper sealing cover 2-1 away from the imbibition cylinder body 1; an experimental core 8 is arranged in the imbibition cylinder body 1.

[0023] like Figure 3 and Figure 4 As shown, the automatic hydraulic press 4 is sealed and connected to the outer walls on the opposite sides of the absorption cylinder body 1 and the outer wall of the lower sealing cover 2-2 away from the absorption cylinder body 1 through screws 16, and the automatic hydraulic presses 4 on the outer walls on the opposite sides of the absorption cylinder body 1 are symmetrically distributed with the axis of the absorption cylinder body 1 as the center; the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is arranged on the extension line of the axis of the absorption cylinder body 1; the automatic hydraulic presses 4 on the opposite sides of the absorption cylinder body 1 are connected to the annular pressure caps 6 through push rods 3, and the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is connected to the circular pressure cap 7 through the push rod 3; the annular pressure cap 6 and the circular pressure cap 7 are arranged inside the absorption cylinder body 1.

[0024] The ends of the annular pressure cap 6 are respectively fitted with the circular pressure cap 7, the circular pressure cap 7 at one end of the annular pressure cap 6 is connected to the upper sealing cover 2-1, an ultrasonic vibrator 9 is arranged between the circular pressure cap 7 at the other end of the annular pressure cap 6 and the lower sealing cover 2-2, the inner wall of the annular pressure cap 6 is fitted with the experimental core 8, and the experimental core 8 is fitted with the circular pressure cap 7; visualization windows 5 are relatively arranged on the outer walls on opposite sides of the imbibition cylinder body 1, a heating sleeve 13 is fitted on the outer wall of the imbibition cylinder body 1, and an insulation sleeve 14 is fitted on the outer wall of the heating sleeve 13, and the two ends of the heating sleeve 13 and the insulation sleeve 14 are respectively fitted with the upper sealing cover 2-1 and the lower sealing cover 2-2.

[0025] A pressure gauge 10-1 is provided on the fluid pipeline 10; sealing rings 15 are respectively provided between the absorption cylinder body 1 and the upper sealing cover 2-1 and the lower sealing cover 2-2; the control system includes a control box 20, the control box 20 is communicatively connected to a computer 21, and the control box 20 is respectively connected to the automatic hydraulic press 4, the ultrasonic vibrator 9, the heating sleeve 13, and the pressurizing device 19 through the wire 17; the pressurizing device 19 is connected to the inside of the absorption cylinder body 1 after passing through the lower sealing cover 2-2 through the fluid pipeline 10; the metering device 11 includes a graduated glass tube, the graduated glass tube is covered with a protective cover 11-1, one end of the protective cover 11-1 is embedded in the upper sealing cover 2-1, and an exhaust valve 12 is provided on the outer wall of the other end.

[0026] like Figure 5 As shown, the annular pressure cover 6 includes an infiltration type annular pressure cover, which is composed of two semicircular tubes bonded together, an infiltration type annular pressure cover is bonded with a pressure mesh 6-2 on the inner wall of the infiltration type annular pressure cover, and a plurality of fluid holes 6-1 are bonded with the outer wall of the infiltration type annular pressure cover, and the pressure mesh 6-2 is connected with the fluid holes 6-1; a rubber sealing gasket 6-4 is arranged between the two semicircular tube bonding surfaces of the infiltration type annular pressure cover, and the two sides of the rubber sealing gasket 6-4 are respectively bonded with the infiltration type annular pressure cover; external threaded interfaces 6-5 are arranged on the outer walls on the opposite sides of the infiltration type annular pressure cover, and the external threaded interfaces 6-5 are connected with the push rod 3.

[0027] like Figure 6 As shown, the annular gland 6 includes a sealed annular gland, which is composed of two semicircular tubes fitted together, a rubber sleeve 6-3 is fitted on the inner wall of the sealed annular gland, a rubber sealing gasket 6-4 is provided between the two semicircular tube fitting surfaces of the sealed annular gland, and both sides of the rubber sealing gasket 6-4 are respectively fitted with the sealed annular gland; external threaded interfaces 6-5 are respectively provided on the outer walls on both sides of the opposite sides of the sealed annular gland, and the external threaded interfaces 6-5 are respectively connected to the push rods 3 on both sides of the absorption cylinder body 1.

[0028] like Figure 7As shown, the circular pressure cap 7 includes a seepage type circular pressure cap, which includes two threaded columns 7-4. The two threaded columns 7-4 are respectively connected to the push rod 3 and the upper sealing cover 2-1 at the end of the seepage cylinder 1 at one end away from the experimental core 8. A circular pressure plate is fixedly connected to the end of the threaded column 7-4 close to the experimental core 8. An annular groove 7-2 is arranged on the outer wall of the circular pressure plate close to the experimental core 8. A plurality of seepage holes 7-1 are opened on the outer wall of the circular pressure plate close to the threaded column 7-4. The seepage holes 7-1 are connected to the annular groove 7-2.

[0029] like Figure 8 As shown, the circular pressure cover 7 includes a sealed circular pressure cover, which includes two threaded columns 7-4. The two threaded columns 7-4 are respectively connected to the push rod 3 and the upper sealing cover 2-1 at the end of the imbibition cylinder 1 at one end away from the experimental core 8. A circular pressure plate is fixedly connected to the end of the threaded column 7-4 close to the experimental core 8. A rubber sealing sheet 7-3 is fitted on the outer wall of the circular pressure plate close to the experimental core 8.

[0030] In the present invention, visualization windows 5 are relatively arranged on the outer walls of both sides of the imbibition cylinder 1, so as to realize the visualization of the imbibition experiment process; automatic hydraulic presses 4 are respectively arranged on both sides and one end of the imbibition cylinder 1, and the automatic hydraulic presses 4 are respectively connected with the annular pressure cap 6 and the circular pressure cap 7 through the push rod 3, and the annular pressure cap 6 or the circular pressure cap 7 is pushed by the automatic hydraulic press 4 through the pressurizing device 19 to squeeze the experimental core 8, so as to simulate the different covering pressure conditions of the experimental core 8 during the imbibition process under the actual reservoir conditions; the heating sleeve 13 is covered on the imbibition cylinder 1, and the imbibition liquid in the imbibition cylinder 1 is heated when the imbibition experiment is carried out, so as to simulate the ambient temperature of the experimental core 8 under the actual reservoir conditions, and the heating sleeve 13 is covered with the heat preservation sleeve 14, It has the function of keeping the imbibition liquid in the imbibition cylinder 1 warm; the fluid pipeline 10 passes through the lower sealing cover 2-2 and is connected with the internal cavity of the imbibition cylinder 1, so as to realize the addition and discharge of the imbibition liquid in the imbibition cylinder 1 and fluid pressurization during the experiment; the volume of oil produced from the core during the experiment can be simply and intuitively recorded by the metering device 11, so as to facilitate the calculation of the core imbibition recovery rate; in the present invention, the automatic hydraulic press 4, the ultrasonic vibrator 9, the heating sleeve 13 and the pressurizing device 19 are respectively connected with the control box 20, and the control box 20 is connected with the computer 21 for communication, and the control of each equipment unit is realized in the operation interface of the computer 21, so as to realize the simulation of the temperature, pressure and other conditions of the actual reservoir conditions of the experimental core 8.

[0031] The experimental core 8 in the present invention includes natural cores and artificial cores in conventional cores and cores with cracks. Cores with different crack shapes are used, and left and right annular pressure caps 6 and upper and lower circular pressure caps 7 are used to wrap the experimental core 8. Different stresses are applied to the core under different boundary conditions, thereby affecting the size of pores and cracks, and evaluating the influence of different stresses on the core infiltration efficiency.

[0032] The method for using the multifunctional pressure-covering static infiltration and absorption experimental device comprises the following steps: S1. Vacuum the experimental core and pressurize it to saturate it with oil. Calculate the saturated oil volume of the experimental core 8 by weighing method. ; S2. Adjust and assemble the multifunctional static imbibition test device, and place the test core 8 into the closed area formed by the annular gland 6 and the circular gland 7, so that the test core 8 fits the annular gland 6 and the circular gland 7; When adjusting and assembling the multifunctional static imbibition experimental device under pressure, when the imbibition experiment simulates the multi-dimensional imbibition process under pressure, the annular gland 6 uses an imbibition-type annular gland, and the circular gland 7 uses an imbibition-type circular gland; when the imbibition experiment simulates the axial imbibition process under pressure, the annular gland 6 uses a sealed annular gland, and the circular gland 7 uses an imbibition-type circular gland; when the imbibition experiment simulates the radial imbibition process under pressure, the annular gland 6 uses an imbibition-type annular gland, and the circular gland 7 uses a sealed circular gland; Adjust and assemble the multifunctional static imbibition test device, place the test core 8 on the circular gland 7, adjust the automatic hydraulic press 4 on one side of the lower sealing cover 2-2 away from the imbibition cylinder 1 so that the two ends of the test core 8 are respectively fitted with the circular gland 7, and then adjust the automatic hydraulic press 4 on the outer walls of the opposite sides of the imbibition cylinder 1 so that the two sides of the test core 8 are respectively fitted with the annular gland 6; S3, filling the imbibition cylinder 1 with imbibition liquid and adjusting the experimental pressure; Open the drain valve 12, add the imbibition liquid into the imbibition cylinder 1 through the pressurizing device 19, close the drain valve 12 after the imbibition liquid seeps out, and continue to add the imbibition liquid until the pressure gauge 10-1 reaches the preset pressure and then stop; S4, start the experiment and record the experimental data regularly; Adjust the temperature of the imbibition liquid in the imbibition cylinder 1, the imbibition liquid pressure in the imbibition cylinder 1, and the axial pressure and radial pressure on the experimental core 8, start the test, and during the test, use the ultrasonic vibrator 9 to regularly drive away the oil droplets imbibed on the surface of the experimental core 8, and record the oil volume produced from the core at that moment , calculate the core imbibition recovery rate at this time ; S5, close the heating jacket 13 and the pressurizing device 19, take out the experimental core 8, and the experiment is completed.

[0033] Core imbibition recovery The calculation formula is as follows: , in, represents the core recovery rate at time t of the imbibition experiment, represents the core oil production volume at time t in the imbibition experiment, It represents the saturated oil volume of the core in the imbibition experiment.

[0034] The assembly process of the multifunctional static imbibition experimental device under covering pressure of the present invention is as follows: a circular pressure cap 7 is installed on the push rod 3 at the bottom of the imbibition cylinder 1, and annular pressure caps 6 are installed on the push rods 3 on both sides of the imbibition cylinder 1, and the experimental core 8 is placed on the circular pressure cap 7 at the bottom. The imbibition cylinder 1 is respectively installed with the upper sealing cover 2-1 and the lower sealing cover 2-2 through threaded combination, and the automatic hydraulic press 4, the ultrasonic vibrator 9, the heating sleeve 13, and the pressurizing device 19 are respectively connected to the control box 20, and the pressurizing device 19 is connected to the imbibition cylinder 1 through the fluid pipeline 10. The pressurizing device 19 is connected to the automatic hydraulic press 4, and the connection status of each unit and the sealing status of the equipment are checked, and the assembly is completed.

[0035] The present invention simulates rock stress in different directions and the imbibition process under the overburden state in an imbibition experiment by using the imbibition type annular gland, the sealing annular gland, the imbibition type circular gland and the sealing circular gland in a reasonable combination.

[0036] like Fig. 9 As shown, the imbibition annular gland and the imbibition circular gland cooperate with each other, and the automatic hydraulic press 4 squeezes the test core 8 through the imbibition annular gland and the imbibition circular gland, simulates radial and axial rock stresses in the imbibition experiment, and simulates the multi-dimensional imbibition process under the overburden state; Fig.10 As shown, the closed annular gland and the imbibition circular gland cooperate with each other, and the automatic hydraulic press 4 squeezes the test core 8 through the closed annular gland and the imbibition circular gland, simulates the axial rock stress in the imbibition experiment, and simulates the axial imbibition process under the overburden state.

[0037] like Fig.11 As shown, the imbibition annular gland and the closed circular gland are matched, and the automatic hydraulic press 4 squeezes the experimental core 8 through the imbibition annular gland and the closed circular gland, simulating radial rock stress in the imbibition experiment and simulating the radial imbibition process under the overburden state. The present invention can visualize, truly and accurately simulate the core imbibition oil production process under formation environmental conditions; it can also scientifically evaluate the spontaneous imbibition capacity of low permeability cores under different boundary conditions.

[0038] Example 1 This embodiment proposes a multifunctional static infiltration and absorption experimental device. Figure 1 As shown, it includes an imbibition body and a control system. The imbibition body is connected to a pressurizing device 19 through a fluid pipeline 10, and the control system is connected to the imbibition body and the pressurizing device 19 through a wire 17 respectively; Figure 2As shown, the imbibition body includes a base 18, on which an imbibition cylinder body 1 is arranged, and the two ends of the imbibition cylinder body 1 are respectively connected with an upper sealing cover 2-1 and a lower sealing cover 2-2, the lower sealing cover 2-2 is arranged in close contact with the base 18 on the side away from the imbibition cylinder body 1, automatic hydraulic presses 4 are respectively arranged on the opposite sides of the imbibition cylinder body 1 and on the side of the lower sealing cover 2-2 away from the imbibition cylinder body 1, and a metering device 11 is arranged on the side of the upper sealing cover 2-1 away from the imbibition cylinder body 1; an experimental core 8 is arranged in the imbibition cylinder body 1.

[0039] Example 2 This embodiment proposes a multifunctional static infiltration and absorption experimental device. Figure 1 As shown, it includes an imbibition body and a control system. The imbibition body is connected to a pressurizing device 19 through a fluid pipeline 10, and the control system is connected to the imbibition body and the pressurizing device 19 through a wire 17 respectively; Figure 2 As shown, the imbibition body includes a base 18, on which an imbibition cylinder body 1 is arranged, and the two ends of the imbibition cylinder body 1 are respectively connected with an upper sealing cover 2-1 and a lower sealing cover 2-2, the lower sealing cover 2-2 is arranged in close contact with the base 18 on the side away from the imbibition cylinder body 1, automatic hydraulic presses 4 are respectively arranged on the opposite sides of the imbibition cylinder body 1 and on the side of the lower sealing cover 2-2 away from the imbibition cylinder body 1, and a metering device 11 is arranged on the side of the upper sealing cover 2-1 away from the imbibition cylinder body 1; an experimental core 8 is arranged in the imbibition cylinder body 1.

[0040] like Figure 3 and Figure 4As shown, the automatic hydraulic press 4 is sealed and connected to the outer walls on the opposite sides of the absorption cylinder body 1 and the outer wall of the lower sealing cover 2-2 away from the absorption cylinder body 1 through screws 16, and the automatic hydraulic presses 4 on the outer walls on the opposite sides of the absorption cylinder body 1 are symmetrically distributed with the axis of the absorption cylinder body 1 as the center; the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is arranged on the extension line of the axis of the absorption cylinder body 1; the automatic hydraulic presses 4 on the opposite sides of the absorption cylinder body 1 are connected to the annular pressure caps 6 through push rods 3, and the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is connected to the circular pressure cap 7 through the push rod 3; the annular pressure cap 6 and the circular pressure cap 7 are arranged inside the absorption cylinder body 1. The ends of the annular pressure cap 6 are respectively fitted with the circular pressure cap 7, the circular pressure cap 7 at one end of the annular pressure cap 6 is connected to the upper sealing cover 2-1, an ultrasonic vibrator 9 is arranged between the circular pressure cap 7 at the other end of the annular pressure cap 6 and the lower sealing cover 2-2, the inner wall of the annular pressure cap 6 is fitted with the experimental core 8, and the experimental core 8 is fitted with the circular pressure cap 7; visualization windows 5 are relatively arranged on the outer walls on opposite sides of the imbibition cylinder body 1, a heating sleeve 13 is fitted on the outer wall of the imbibition cylinder body 1, and an insulation sleeve 14 is fitted on the outer wall of the heating sleeve 13, and the two ends of the heating sleeve 13 and the insulation sleeve 14 are respectively fitted with the upper sealing cover 2-1 and the lower sealing cover 2-2. A pressure gauge 10-1 is provided on the fluid pipeline 10; sealing rings 15 are respectively provided between the absorption cylinder body 1 and the upper sealing cover 2-1 and the lower sealing cover 2-2; the control system includes a control box 20, the control box 20 is communicatively connected to a computer 21, and the control box 20 is respectively connected to the automatic hydraulic press 4, the ultrasonic vibrator 9, the heating sleeve 13, and the pressurizing device 19 through the wire 17; the pressurizing device 19 is connected to the inside of the absorption cylinder body 1 after passing through the lower sealing cover 2-2 through the fluid pipeline 10; the metering device 11 includes a graduated glass tube, the graduated glass tube is covered with a protective cover 11-1, one end of the protective cover 11-1 is embedded in the upper sealing cover 2-1, and an exhaust valve 12 is provided on the outer wall of the other end.

[0041] Example 3 This embodiment proposes a multifunctional static infiltration and absorption experimental device. Figure 1 As shown, it includes an imbibition body and a control system. The imbibition body is connected to a pressurizing device 19 through a fluid pipeline 10, and the control system is connected to the imbibition body and the pressurizing device 19 through a wire 17 respectively; Figure 2 As shown, the imbibition body includes a base 18, on which an imbibition cylinder body 1 is arranged, and the two ends of the imbibition cylinder body 1 are respectively connected with an upper sealing cover 2-1 and a lower sealing cover 2-2, the lower sealing cover 2-2 is arranged in close contact with the base 18 on the side away from the imbibition cylinder body 1, automatic hydraulic presses 4 are respectively arranged on the opposite sides of the imbibition cylinder body 1 and on the side of the lower sealing cover 2-2 away from the imbibition cylinder body 1, and a metering device 11 is arranged on the side of the upper sealing cover 2-1 away from the imbibition cylinder body 1; an experimental core 8 is arranged in the imbibition cylinder body 1.

[0042] like Figure 3 and Figure 4 As shown, the automatic hydraulic press 4 is sealed and connected to the outer walls on the opposite sides of the absorption cylinder body 1 and the outer wall of the lower sealing cover 2-2 away from the absorption cylinder body 1 through screws 16, and the automatic hydraulic presses 4 on the outer walls on the opposite sides of the absorption cylinder body 1 are symmetrically distributed with the axis of the absorption cylinder body 1 as the center; the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is arranged on the extension line of the axis of the absorption cylinder body 1; the automatic hydraulic presses 4 on the opposite sides of the absorption cylinder body 1 are connected to the annular pressure caps 6 through push rods 3, and the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is connected to the circular pressure cap 7 through the push rod 3; the annular pressure cap 6 and the circular pressure cap 7 are arranged inside the absorption cylinder body 1. The ends of the annular pressure cap 6 are respectively fitted with the circular pressure cap 7, the circular pressure cap 7 at one end of the annular pressure cap 6 is connected to the upper sealing cover 2-1, an ultrasonic vibrator 9 is arranged between the circular pressure cap 7 at the other end of the annular pressure cap 6 and the lower sealing cover 2-2, the inner wall of the annular pressure cap 6 is fitted with the experimental core 8, and the experimental core 8 is fitted with the circular pressure cap 7; visualization windows 5 are relatively arranged on the outer walls on opposite sides of the imbibition cylinder body 1, a heating sleeve 13 is fitted on the outer wall of the imbibition cylinder body 1, and an insulation sleeve 14 is fitted on the outer wall of the heating sleeve 13, and the two ends of the heating sleeve 13 and the insulation sleeve 14 are respectively fitted with the upper sealing cover 2-1 and the lower sealing cover 2-2. A pressure gauge 10-1 is provided on the fluid pipeline 10; sealing rings 15 are respectively provided between the absorption cylinder body 1 and the upper sealing cover 2-1 and the lower sealing cover 2-2; the control system includes a control box 20, the control box 20 is communicatively connected to a computer 21, and the control box 20 is respectively connected to the automatic hydraulic press 4, the ultrasonic vibrator 9, the heating sleeve 13, and the pressurizing device 19 through the wire 17; the pressurizing device 19 is connected to the inside of the absorption cylinder body 1 after passing through the lower sealing cover 2-2 through the fluid pipeline 10; the metering device 11 includes a graduated glass tube, the graduated glass tube is covered with a protective cover 11-1, one end of the protective cover 11-1 is embedded in the upper sealing cover 2-1, and an exhaust valve 12 is provided on the outer wall of the other end.

[0043] like Figure 5 As shown, the annular gland 6 includes an infiltration type annular gland, which is composed of two semicircular tubes bonded together, an infiltration pressure net 6-2 is bonded on the inner wall of the infiltration type annular gland, and a plurality of fluid holes 6-1 are bonded on the outer wall of the infiltration type annular gland, and the infiltration pressure net 6-2 is connected with the fluid holes 6-1; a rubber sealing gasket 6-4 is provided between the bonding surfaces of the two semicircular tubes of the infiltration type annular gland, and the two sides of the rubber sealing gasket 6-4 are bonded to the infiltration type annular gland respectively; external threaded interfaces 6-5 are provided on the outer walls on opposite sides of the infiltration type annular gland, and the external threaded interfaces 6-5 are connected to the push rod 3. Figure 7As shown, the circular pressure cap 7 includes a seepage type circular pressure cap, which includes two threaded columns 7-4. The two threaded columns 7-4 are respectively connected to the push rod 3 and the upper sealing cover 2-1 at the end of the seepage cylinder 1 at one end away from the experimental core 8. A circular pressure plate is fixedly connected to the end of the threaded column 7-4 close to the experimental core 8. An annular groove 7-2 is arranged on the outer wall of the circular pressure plate close to the experimental core 8. A plurality of seepage holes 7-1 are opened on the outer wall of the circular pressure plate close to the threaded column 7-4. The seepage holes 7-1 are connected to the annular groove 7-2.

[0044] like Fig. 9 As shown, this embodiment provides an experimental device for simulating radial and axial rock stresses in an imbibition experiment, simulating a multi-dimensional imbibition process under an overburden state.

[0045] Example 4 This embodiment proposes a multifunctional static infiltration and absorption experimental device. Figure 1 As shown, it includes an imbibition body and a control system. The imbibition body is connected to a pressurizing device 19 through a fluid pipeline 10, and the control system is connected to the imbibition body and the pressurizing device 19 through a wire 17 respectively; Figure 2 As shown, the imbibition body includes a base 18, on which an imbibition cylinder body 1 is arranged, and the two ends of the imbibition cylinder body 1 are respectively connected with an upper sealing cover 2-1 and a lower sealing cover 2-2, the lower sealing cover 2-2 is arranged in close contact with the base 18 on the side away from the imbibition cylinder body 1, automatic hydraulic presses 4 are respectively arranged on the opposite sides of the imbibition cylinder body 1 and on the side of the lower sealing cover 2-2 away from the imbibition cylinder body 1, and a metering device 11 is arranged on the side of the upper sealing cover 2-1 away from the imbibition cylinder body 1; an experimental core 8 is arranged in the imbibition cylinder body 1.

[0046] like Figure 3 and Figure 4As shown, the automatic hydraulic press 4 is sealed and connected to the outer walls on the opposite sides of the absorption cylinder body 1 and the outer wall of the lower sealing cover 2-2 away from the absorption cylinder body 1 through screws 16, and the automatic hydraulic presses 4 on the outer walls on the opposite sides of the absorption cylinder body 1 are symmetrically distributed with the axis of the absorption cylinder body 1 as the center; the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is arranged on the extension line of the axis of the absorption cylinder body 1; the automatic hydraulic presses 4 on the opposite sides of the absorption cylinder body 1 are connected to the annular pressure caps 6 through push rods 3, and the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is connected to the circular pressure cap 7 through the push rod 3; the annular pressure cap 6 and the circular pressure cap 7 are arranged inside the absorption cylinder body 1. The ends of the annular pressure cap 6 are respectively fitted with the circular pressure cap 7, the circular pressure cap 7 at one end of the annular pressure cap 6 is connected to the upper sealing cover 2-1, an ultrasonic vibrator 9 is arranged between the circular pressure cap 7 at the other end of the annular pressure cap 6 and the lower sealing cover 2-2, the inner wall of the annular pressure cap 6 is fitted with the experimental core 8, and the experimental core 8 is fitted with the circular pressure cap 7; visualization windows 5 are relatively arranged on the outer walls on opposite sides of the imbibition cylinder body 1, a heating sleeve 13 is fitted on the outer wall of the imbibition cylinder body 1, and an insulation sleeve 14 is fitted on the outer wall of the heating sleeve 13, and the two ends of the heating sleeve 13 and the insulation sleeve 14 are respectively fitted with the upper sealing cover 2-1 and the lower sealing cover 2-2. A pressure gauge 10-1 is provided on the fluid pipeline 10; sealing rings 15 are respectively provided between the absorption cylinder body 1 and the upper sealing cover 2-1 and the lower sealing cover 2-2; the control system includes a control box 20, the control box 20 is communicatively connected to a computer 21, and the control box 20 is respectively connected to the automatic hydraulic press 4, the ultrasonic vibrator 9, the heating sleeve 13, and the pressurizing device 19 through the wire 17; the pressurizing device 19 is connected to the inside of the absorption cylinder body 1 after passing through the lower sealing cover 2-2 through the fluid pipeline 10; the metering device 11 includes a graduated glass tube, the graduated glass tube is covered with a protective cover 11-1, one end of the protective cover 11-1 is embedded in the upper sealing cover 2-1, and an exhaust valve 12 is provided on the outer wall of the other end.

[0047] like Figure 6 As shown, the annular gland 6 includes a sealed annular gland, which is composed of two semicircular tubes fitted together. A rubber sleeve 6-3 is fitted on the inner wall of the sealed annular gland, and a rubber sealing gasket 6-4 is provided between the two semicircular tube fitting surfaces of the sealed annular gland. Both sides of the rubber sealing gasket 6-4 are fitted with the sealed annular gland respectively; external thread interfaces 6-5 are respectively provided on the outer walls of the opposite sides of the sealed annular gland, and the external thread interfaces 6-5 are respectively connected to the push rods 3 on both sides of the infiltration and absorption cylinder 1. Figure 7As shown, the circular pressure cap 7 includes a seepage type circular pressure cap, which includes two threaded columns 7-4. The two threaded columns 7-4 are respectively connected to the push rod 3 and the upper sealing cover 2-1 at the end of the seepage cylinder 1 at one end away from the experimental core 8. A circular pressure plate is fixedly connected to the end of the threaded column 7-4 close to the experimental core 8. An annular groove 7-2 is arranged on the outer wall of the circular pressure plate close to the experimental core 8. A plurality of seepage holes 7-1 are opened on the outer wall of the circular pressure plate close to the threaded column 7-4. The seepage holes 7-1 are connected to the annular groove 7-2.

[0048] like Fig.10 As shown, this embodiment provides an experimental device for simulating axial rock stress in an imbibition experiment, simulating the axial imbibition process under an overburden state.

[0049] Example 5 This embodiment proposes a multifunctional static infiltration and absorption experimental device. Figure 1 As shown, it includes an imbibition body and a control system. The imbibition body is connected to a pressurizing device 19 through a fluid pipeline 10, and the control system is connected to the imbibition body and the pressurizing device 19 through a wire 17 respectively; Figure 2 As shown, the imbibition body includes a base 18, on which an imbibition cylinder 1 is arranged, and the ends of the imbibition cylinder 1 are respectively connected to an upper sealing cover 2-1 and a lower sealing cover 2-2, and the lower sealing cover 2-2 is arranged in close contact with the base 18 on the side away from the imbibition cylinder 1, and automatic hydraulic presses 4 are respectively arranged on the opposite sides of the imbibition cylinder 1 and on the side of the lower sealing cover 2-2 away from the imbibition cylinder 1, and a metering device 11 is arranged on the side of the upper sealing cover 2-1 away from the imbibition cylinder 1; an experimental core 8 is arranged in the imbibition cylinder 1. Figure 3 and Figure 4As shown, the automatic hydraulic press 4 is sealed and connected to the outer walls on the opposite sides of the absorption cylinder body 1 and the outer wall of the lower sealing cover 2-2 away from the absorption cylinder body 1 through screws 16, and the automatic hydraulic presses 4 on the outer walls on the opposite sides of the absorption cylinder body 1 are symmetrically distributed with the axis of the absorption cylinder body 1 as the center; the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is arranged on the extension line of the axis of the absorption cylinder body 1; the automatic hydraulic presses 4 on the opposite sides of the absorption cylinder body 1 are connected to the annular pressure caps 6 through push rods 3, and the automatic hydraulic press 4 on the side of the lower sealing cover 2-2 away from the absorption cylinder body 1 is connected to the circular pressure cap 7 through the push rod 3; the annular pressure cap 6 and the circular pressure cap 7 are arranged inside the absorption cylinder body 1. The ends of the annular pressure cap 6 are respectively fitted with the circular pressure cap 7, the circular pressure cap 7 at one end of the annular pressure cap 6 is connected to the upper sealing cover 2-1, an ultrasonic vibrator 9 is arranged between the circular pressure cap 7 at the other end of the annular pressure cap 6 and the lower sealing cover 2-2, the inner wall of the annular pressure cap 6 is fitted with the experimental core 8, and the experimental core 8 is fitted with the circular pressure cap 7; visualization windows 5 are relatively arranged on the outer walls on opposite sides of the imbibition cylinder body 1, a heating sleeve 13 is fitted on the outer wall of the imbibition cylinder body 1, and an insulation sleeve 14 is fitted on the outer wall of the heating sleeve 13, and the two ends of the heating sleeve 13 and the insulation sleeve 14 are respectively fitted with the upper sealing cover 2-1 and the lower sealing cover 2-2. A pressure gauge 10-1 is provided on the fluid pipeline 10; sealing rings 15 are respectively provided between the absorption cylinder body 1 and the upper sealing cover 2-1 and the lower sealing cover 2-2; the control system includes a control box 20, the control box 20 is communicatively connected to a computer 21, and the control box 20 is respectively connected to the automatic hydraulic press 4, the ultrasonic vibrator 9, the heating sleeve 13, and the pressurizing device 19 through the wire 17; the pressurizing device 19 is connected to the inside of the absorption cylinder body 1 after passing through the lower sealing cover 2-2 through the fluid pipeline 10; the metering device 11 includes a graduated glass tube, the graduated glass tube is covered with a protective cover 11-1, one end of the protective cover 11-1 is embedded in the upper sealing cover 2-1, and an exhaust valve 12 is provided on the outer wall of the other end.

[0050] like Figure 5 As shown, the annular gland 6 includes an infiltration type annular gland, which is composed of two semicircular tubes bonded together, an infiltration pressure net 6-2 is bonded on the inner wall of the infiltration type annular gland, and a plurality of fluid holes 6-1 are bonded on the outer wall of the infiltration type annular gland, and the infiltration pressure net 6-2 is connected with the fluid holes 6-1; a rubber sealing gasket 6-4 is provided between the bonding surfaces of the two semicircular tubes of the infiltration type annular gland, and the two sides of the rubber sealing gasket 6-4 are bonded to the infiltration type annular gland respectively; external threaded interfaces 6-5 are provided on the outer walls on opposite sides of the infiltration type annular gland, and the external threaded interfaces 6-5 are connected to the push rod 3. Figure 8As shown, the circular pressure cover 7 includes a sealed circular pressure cover, which includes two threaded columns 7-4. The two threaded columns 7-4 are respectively connected to the push rod 3 and the upper sealing cover 2-1 at the end of the imbibition cylinder 1 at one end away from the experimental core 8. A circular pressure plate is fixedly connected to the end of the threaded column 7-4 close to the experimental core 8. A rubber sealing sheet 7-3 is fitted on the outer wall of the circular pressure plate close to the experimental core 8.

[0051] like Fig.11 As shown, this embodiment provides an experimental device for simulating radial rock stress in an imbibition experiment, simulating the radial imbibition process under an overburden state.

[0052] Example 6 This embodiment provides a method for using a multifunctional static infiltration and absorption experimental device, including the following steps: The method for using the multifunctional pressure-covering static infiltration and absorption experimental device comprises the following steps: S1, vacuuming the experimental core and pressurizing it to saturate it with oil, and calculating the core saturated oil volume of the experimental core 8 by weighing method; S2. Adjust and assemble the multifunctional static imbibition test device, and place the test core 8 into the closed area formed by the annular gland 6 and the circular gland 7, so that the test core 8 fits the annular gland 6 and the circular gland 7; S3, filling the imbibition cylinder 1 with imbibition liquid and adjusting the experimental pressure; Open the drain valve 12, add the imbibition liquid into the imbibition cylinder 1 through the pressurizing device 19, close the drain valve 12 after the imbibition liquid seeps out, and continue to add the imbibition liquid until the pressure gauge 10-1 reaches the preset pressure and then stop; S4, start the experiment and record the experimental data regularly; Adjust the temperature of the imbibition liquid in the imbibition cylinder 1, the pressure of the imbibition liquid in the imbibition cylinder 1, and the axial pressure and radial pressure on the experimental core 8, start the test, and during the test, use the ultrasonic vibrator 9 to regularly drive away the oil droplets imbibed on the surface of the experimental core 8, and record the core oil production volume at that moment, and calculate the core imbibition recovery rate at that moment; S5, close the heating jacket 13 and the pressurizing device 19, take out the experimental core 8, and the experiment is completed.

Claims

1. Multifunctional static infiltration and absorption experimental device, characterized in that: The invention comprises an imbibition body and a control system, wherein the imbibition body is connected to a pressure device (19) via a fluid pipeline (10), and the control system is connected to the imbibition body and the pressure device (19) via a wire (17). The imbibition body comprises a base (18), an imbibition cylinder (1) is arranged on the base (18), and the two ends of the imbibition cylinder (1) are respectively connected to an upper sealing cover (2-1) and a lower sealing cover (2-2), and the lower sealing cover (2-2) is arranged in close contact with the base (18) on a side away from the imbibition cylinder (1), automatic hydraulic presses (4) are respectively arranged on opposite sides of the imbibition cylinder (1) and on a side of the lower sealing cover (2-2) away from the imbibition cylinder (1), and a metering device (11) is arranged on a side of the upper sealing cover (2-1) away from the imbibition cylinder (1); and an experimental rock core (8) is arranged in the imbibition cylinder (1).

2. The multifunctional static absorption test device under pressure according to claim 1 is characterized in that: The automatic hydraulic press (4) is sealedly connected to the outer walls of the two opposite sides of the absorption cylinder (1) and the outer wall of the lower sealing cover (2-2) away from the absorption cylinder (1) through screws (16), and the automatic hydraulic presses (4) on the outer walls of the two opposite sides of the absorption cylinder (1) are symmetrically distributed with the axis of the absorption cylinder (1) as the center; the automatic hydraulic press (4) on the side of the lower sealing cover (2-2) away from the absorption cylinder (1) is arranged on the extension line of the axis of the absorption cylinder (1); the automatic hydraulic presses (4) on the two opposite sides of the absorption cylinder (1) are connected to annular pressure covers (6) through push rods (3), and the automatic hydraulic press (4) on the side of the lower sealing cover (2-2) away from the absorption cylinder (1) is connected to a circular pressure cover (7) through a push rod (3); the annular pressure cover (6) and the circular pressure cover (7) are arranged inside the absorption cylinder (1).

3. The multifunctional static infiltration test device according to claim 2 is characterized in that: The ends of the annular gland (6) are respectively fitted with the circular gland (7); the circular gland (7) at one end of the annular gland (6) is connected to the upper sealing cover (2-1); an ultrasonic vibrator (9) is arranged between the circular gland (7) at the other end of the annular gland (6) and the lower sealing cover (2-2); the inner wall of the annular gland (6) is fitted with the experimental core (8); and the experimental core (8) is fitted with the circular gland (7); visual windows (5) are arranged on the outer walls of the two opposite sides of the infiltration cylinder (1); a heating sleeve (13) is fitted on the outer wall of the infiltration cylinder (1); a heat-insulating sleeve (14) is fitted on the outer wall of the heating sleeve (13); and the two ends of the heating sleeve (13) and the heat-insulating sleeve (14) are respectively fitted with the upper sealing cover (2-1) and the lower sealing cover (2-2).

4. The multifunctional static infiltration test device according to claim 3 is characterized in that: The fluid pipeline (10) is provided with a pressure gauge (10-1); sealing rings (15) are respectively provided between the absorption cylinder (1) and the upper sealing cover (2-1) and the lower sealing cover (2-2); the control system comprises a control box (20), the control box (20) is communicatively connected to a computer (21), and the control box (20) is respectively connected to an automatic hydraulic press (4), an ultrasonic vibrator (9), a heating sleeve (13), and a pressurizing device (19) through a wire (17); the pressurizing device (19) is connected to the interior of the absorption cylinder (1) after passing through the lower sealing cover (2-2) through the fluid pipeline (10); the metering device (11) comprises a graduated glass tube, the graduated glass tube is covered with a protective sleeve (11-1), one end of the protective sleeve (11-1) is embedded in the upper sealing cover (2-1), and an exhaust valve (12) is provided on the outer wall of the other end.

5. The multifunctional static infiltration test device under pressure according to claim 4 is characterized in that: The annular pressure cover (6) comprises an infiltration type annular pressure cover, which is composed of two semicircular tubes bonded together, an infiltration pressure net (6-2) is bonded on the inner wall of the infiltration type annular pressure cover, and a plurality of fluid holes (6-1) are bonded on the outer wall of the infiltration type annular pressure cover, and the infiltration pressure net (6-2) is connected with the fluid holes (6-1); a rubber sealing gasket (6-4) is provided between the two semicircular tube bonding surfaces of the infiltration type annular pressure cover, and the two sides of the rubber sealing gasket (6-4) are respectively bonded with the infiltration type annular pressure cover; external threaded interfaces (6-5) are provided on the outer walls on opposite sides of the infiltration type annular pressure cover, and the external threaded interfaces (6-5) are connected to the push rod (3).

6. The multifunctional static infiltration test device under pressure according to claim 4 is characterized in that: The annular gland (6) comprises a sealing annular gland, which is composed of two semicircular tubes fitted together, a rubber sleeve (6-3) is fitted on the inner wall of the sealing annular gland, a rubber sealing gasket (6-4) is provided between the two semicircular tube fitting surfaces of the sealing annular gland, and the two sides of the rubber sealing gasket (6-4) are respectively fitted with the sealing annular gland; external threaded interfaces (6-5) are respectively provided on the outer walls on the opposite sides of the sealing annular gland, and the external threaded interfaces (6-5) are respectively connected to the push rods (3) on the two sides of the absorption cylinder (1).

7. The multifunctional static infiltration and absorption experimental device according to claim 5 or 6, characterized in that: The circular pressure cap (7) comprises a seepage type circular pressure cap, and the seepage type circular pressure cap comprises two threaded columns (7-4), and the ends of the two threaded columns (7-4) away from the experimental core (8) are respectively connected to the push rod (3) and the upper sealing cover (2-1) at the end of the seepage cylinder (1), and the end of the threaded column (7-4) close to the experimental core (8) is fixedly connected to a circular pressure plate, and an annular groove (7-2) is arranged on the outer wall of the circular pressure plate on the side close to the experimental core (8), and a plurality of seepage holes (7-1) are opened on the outer wall of the circular pressure plate on the side close to the threaded column (7-4), and the seepage holes (7-1) are connected to the annular groove (7-2).

8. The multifunctional static absorption test device under pressure according to claim 5 or 6, characterized in that: The circular pressure cover (7) comprises a sealed circular pressure cover, and the sealed circular pressure cover comprises two threaded columns (7-4), and the ends of the two threaded columns (7-4) away from the experimental core (8) are respectively connected to the push rod (3) at the end of the imbibition cylinder (1) and the upper sealing cover (2-1), and the end of the threaded column (7-4) close to the experimental core (8) is fixedly connected to a circular pressure plate, and the outer wall of the circular pressure plate close to the experimental core (8) is fitted with a rubber sealing sheet (7-3).

9. The method for using the multifunctional static infiltration and absorption experimental device is characterized in that: The following steps are involved: S1. Vacuum the experimental core and pressurize it to saturate it with oil. Calculate the saturated oil volume of the experimental core (8) by weighing. ; S2, adjusting and assembling the multifunctional static imbibition test device, placing the test core (8) into the closed area formed by the annular gland (6) and the circular gland (7), so that the test core (8) fits the annular gland (6) and the circular gland (7); S3, filling the imbibition cylinder (1) with imbibition liquid and adjusting the experimental pressure; S4, start the experiment and record the experimental data regularly; S5. Turn off the heating jacket (13) and the pressurizing device (19), take out the experimental core (8), and the experiment is completed.

10. The method for using the multifunctional static infiltration and absorption experimental device according to claim 9, characterized in that: The S2 comprises the following steps: adjusting and assembling the multifunctional static imbibition test device, placing the test core (8) on the circular pressure cap (7), adjusting the automatic hydraulic press (4) on the side of the lower sealing cover (2-2) away from the imbibition cylinder (1) so that the two ends of the test core (8) are respectively fitted with the circular pressure cap (7), and then adjusting the automatic hydraulic press (4) on the outer walls of the two opposite sides of the imbibition cylinder (1) so that the two sides of the test core (8) are respectively fitted with the annular pressure cap (6); When the multifunctional static suction test device under pressure is adjusted and assembled, when the suction test simulates the multi-dimensional suction process under pressure, the annular gland (6) uses a suction-type annular gland, and the circular gland (7) uses a suction-type circular gland; when the suction test simulates the axial suction process under pressure, the annular gland (6) uses a sealing annular gland, and the circular gland (7) uses a suction-type circular gland; when the suction test simulates the radial suction process under pressure, the annular gland (6) uses a suction-type annular gland, and the circular gland (7) uses a sealing circular gland; The step S3 comprises the following steps: opening the drain valve (12), adding imbibition liquid into the imbibition cylinder (1) through the pressurizing device (19), closing the drain valve (12) after the imbibition liquid seeps out, and continuing to add imbibition liquid until the pressure gauge (10-1) reaches a preset pressure and then stops; The step S4 comprises the following steps: adjusting the temperature of the imbibition liquid in the imbibition cylinder (1), the pressure of the imbibition liquid in the imbibition cylinder (1), the axial pressure and the radial pressure on the experimental core (8), starting the test and, during the test, using an ultrasonic vibrator (9) to periodically drive away the oil droplets imbibed on the surface of the experimental core (8), and recording the oil volume produced from the core at that moment. , calculate the core imbibition recovery rate at this time ; The core imbibition recovery rate The calculation formula is as follows: ， in, represents the core recovery rate at time t of the imbibition experiment, represents the core oil production volume at time t in the imbibition experiment, It represents the saturated oil volume of the core in the imbibition experiment.

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