Pressure-controllable clamping and dipping device and method for cementing treatment of rock sample

Abstract

The invention discloses a pressure-controllable clamping and dipping device and method for rock sample cementing treatment, and belongs to the technical field of rock sample tests. The device consists of a radial centering pressurizing module, an independent heating container and a hydraulic control system, the independent heating container and a saucepan with a built-in thermometer are fixed on a base, and a heating wire is arranged at the bottom of the base. An annular hydraulic oil groove is integrated in the base and connected with an internal pushing rod through multiple sets of hydraulic oil pipes, a sample contact plate is installed at the tail end of the pushing rod, and a supporting block is arranged on the outer side for positioning. The radial centering and pressurizing module is erected above the circumferential centering and pressurizing module; and an internal pushing rod is connected with the pressure transmission plate and the sample contact plate. A manual hydraulic pump is connected with an oil pump pressurization connector through a quick connector, a hydraulic oil pipe is provided with a high-precision pressure gauge and a control valve, a separator is laid in a sample contact area, and all the components cooperate to achieve cementing treatment of a rock sample at constant temperature and constant pressure.

Description

Technical Field

[0001] This invention belongs to the field of rock sample testing technology, specifically relating to a controllable pressure clamping and impregnation device and method for cementing treatment of rock samples. Background Technology

[0002] In experimental studies in fields such as geological engineering, rock mechanics, and unconventional oil and gas development, it is often necessary to observe the microstructure of rock (including coal-bearing rocks) samples to analyze their porosity, fracture development characteristics, and mineral distribution patterns. For rock samples with low strength, fractures, or well-developed fractures, direct physical sample preparation such as cutting and grinding can easily damage the sample structure, making it impossible to obtain effective thin sections for observation. Therefore, the industry commonly adopts an impregnation and cementation pretreatment process: the sample is immersed in molten low-melting-point cementing material (such as a rosin-paraffin mixture), and under external pressure, the cementitious material is forced to penetrate into the microfractures. After cooling and solidification, the sample is consolidated, providing structural support for subsequent sample preparation.

[0003] Currently, laboratories mostly use simple combined equipment to complete the above processes, which has the following technical drawbacks:

[0004] First, the sample clamping and positioning methods are outdated. Existing technologies typically use tweezers or wires to hold the sample and place it into the heating container. This process can easily cause the sample to tip over or slip, resulting in uneven impregnation and posing a risk of burns to operators from the high-temperature colloid.

[0005] Secondly, the methods of applying and controlling pressure are crude. A common practice is to apply pressure by placing weights above the sample. However, the pressure cannot be precisely adjusted or displayed in real time, and it is difficult to maintain a constant pressure. Insufficient pressure results in poor gel penetration, while excessive pressure can crush fragile samples. Furthermore, the experimental process lacks effective monitoring and feedback mechanisms.

[0006] Third, post-operation cleaning is difficult. After the sample is removed, the adhesive material adhering to the surface cools and solidifies, making it difficult to clean. This easily contaminates the fixtures, work surface, and experimental environment. Repeated cleaning is time-consuming and labor-intensive, and may also cause cross-contamination in subsequent experiments.

[0007] Fourth, the process flow is fragmented. The heating and impregnation process and the pressure application process are often separate operations. For example, the sample is loaded outside the container before being immersed in the adhesive, or it is loaded separately after immersion. This causes the temperature of the adhesive to drop rapidly and the fluidity to decrease, affecting the penetration depth and uniformity of the bonding material, and ultimately restricting the quality of sample pretreatment.

[0008] Chinese Patent CN119064132A discloses a sample clamping and loading assembly, a rock sample testing device, and its usage method. The device includes a variable-material-property rubber sealing cylinder and a clamping and fixing base, achieving sealed loading by wrapping the sample with the variable-material-property rubber sealing cylinder. However, this technical solution has the following shortcomings: the design of the rubber sealing cylinder wrapping the sample hinders the cementing material from fully contacting the sample surface and internal cracks, making full immersion penetration impossible. It is only suitable for sealed loading scenarios in mechanical testing and cannot meet the technical requirements for full penetration of cementing materials in the cementing treatment process of rock samples.

[0009] In summary, the existing technology lacks a dedicated device that can controllably clamp rock samples under constant temperature and pressure conditions while ensuring sufficient penetration of cementing materials. There is an urgent need for those skilled in the art to solve the above-mentioned technical problems. Summary of the Invention

[0010] To solve the above-mentioned technical problems, this invention uses a controllable pressure clamping method to hold rock samples, employing dual independent hydraulic drives and real-time feedback via a manually connected hydraulic injection port and a high-precision pressure gauge.

[0011] This invention discloses a controllable pressure clamping and impregnation device for cementing treatment of rock samples, comprising: a frame module, a dual-oil-circuit hydraulic drive module, a radial centering pressurization module, an independent heating container, and an isolating component; the dual-oil-circuit hydraulic drive module is mounted on the frame module and is used to support the dual-oil-circuit hydraulic drive module; the dual-oil-circuit hydraulic drive module is connected to the radial centering pressurization module for adjusting the clamping force of the radial centering pressurization module on the rock sample; the independent heating container is disposed between the radial centering pressurization module and the frame module, and the radial centering pressurization module is used to clamp the rock sample; the isolating component is disposed between the radial centering pressurization module and the rock sample.

[0012] By adopting the above technical solution, a frame module provides stable support, a dual-oil-circuit hydraulic drive module enables precise adjustment of clamping force, a radially centered pressure module ensures uniform stress on the rock sample, an independent heating container precisely controls the temperature environment of the cementing material, and an isolation component effectively isolates the rock sample from cross-contamination between the hydraulic system and the cementing material. The overall structure achieves coordinated operation of controllable pressure clamping and constant-temperature immersion, significantly improving the uniformity and stability of the rock sample cementation process, providing a morphologically intact and fully cemented sample foundation for subsequent experimental testing.

[0013] Furthermore, the frame module includes a base, a fixing block, and a support block; the fixing block is vertically fixed to the center of the upper surface of the base, and the support block is symmetrically fixed to the upper surface of the base, located on the left and right sides directly below the fixing block; the bottom of the base is provided with adjustable support feet with an adjustment range of 0-30mm.

[0014] The dual-circuit hydraulic drive module includes an annular hydraulic oil tank, hydraulic oil pipe one, hydraulic oil pipe two, control valves, high-precision pressure gauges, and an oil pump pressurization interface. The annular hydraulic oil tank is installed on the top of the fixed block. One end of hydraulic oil pipe one and hydraulic oil pipe two are connected to the annular hydraulic oil tank, and the other end is connected to the radial centering pressurization module. Two control valves are respectively installed on hydraulic oil pipe one and hydraulic oil pipe two. At least four sets of high-precision pressure gauges are respectively installed at the inlet and outlet of hydraulic oil pipe one and hydraulic oil pipe two. The oil pump pressurization interface is installed on the annular hydraulic oil tank, and the interface is adapted to a standard hydraulic pump quick connector.

[0015] The radial centering pressurization module includes at least four internal push rods, a corresponding number of pressure transmission plates, and sample contact plates;

[0016] The number of support blocks corresponds to the number of internal push rods, and they are evenly arranged circumferentially along the upper surface of the base; each internal push rod is coaxially installed in the guide hole of the corresponding support block, with its axis pointing to the central sample station, and the included angle between the axes of adjacent push rods is equal.

[0017] The pressure transmission plate is disposed between the internal push rod and the sample contact plate. The inner end of the internal push rod is fixedly connected to the outer end face of the pressure transmission plate through a flange structure. The sample contact plate is fixed to the inner end face of the pressure transmission plate by a bolt assembly, and the plate surface of the sample contact plate is perpendicular to the axis of the corresponding internal push rod. The inner end faces of all the sample contact plates together enclose a circumferential clamping space adapted to the shape of the rock sample.

[0018] At least four internal propulsion rods are divided into two groups, with the axes of the two propulsion rods in each group being collinear and pointing towards the central sample station; at least two groups of the internal propulsion rods share the same hydraulic oil pipe, with hydraulic oil pipe one and hydraulic oil pipe two respectively connected to an annular hydraulic oil groove, and the internal propulsion rods synchronously receive hydraulic driving force to achieve circumferential synchronous equidistant propulsion, forming a uniformly distributed circumferential symmetrical clamping force on the rock sample;

[0019] The independent heating container is placed on the upper surface of the base and located directly below the central sample station. It includes a detachable cooking pot, a heating wire, and a thermometer. The heating wire is embedded in the bottom of the base, and the thermometer is inserted into the pot from the side wall of the cooking pot.

[0020] By adopting the above technical solutions, the adjustable support feet of the frame module ensure the horizontal stability of the device and adapt to different experimental environments; the annular oil groove, multiple sets of high-precision pressure gauges, and independent control valves of the dual-oil-circuit hydraulic drive module enable real-time monitoring and precise control of hydraulic pressure, and the standard connector of the oil pump interface improves equipment compatibility; the grouped collinear design of multiple push rods of the radial centering pressurization module ensures absolute symmetry of circumferential force on the rock sample, and the combined structure of the pressure transmission plate and sample contact plate not only improves pressure transmission efficiency but also allows for adaptation to rock samples of different sizes by replacing the sample contact plate; the embedded heating wire and sidewall thermometer of the independent heating container achieve constant temperature control of the cementing material, providing a stable temperature environment for the cementing process. This comprehensively improves the ease of operation, control accuracy, and adaptability of the device.

[0021] Furthermore, the sample contact plate of the radial centering pressurization module is a detachable structure and is fixedly connected to the internal push rod through the pressure transmission plate (8); the synchronous push pressure range of the internal push rod is 0.1-1MPa.

[0022] By adopting the above technical solution, the detachable design of the sample contact plate allows for flexible replacement of the appropriate contact plate according to the shape and size of the rock sample, greatly expanding the applicability of the device; the pressure adjustment range of 0.1-1MPa avoids the rock sample from breaking due to excessive pressure, and ensures the stable clamping of the sample during the cementation process, ensuring that the sample maintains its morphological integrity during the impregnation and pressure holding stages, which is especially suitable for the processing of rock samples with developed fissures and brittle texture.

[0023] Furthermore, the internal push rod is driven by hydraulic oil supply through hydraulic oil pipe one and hydraulic oil pipe two, which are respectively connected to the annular hydraulic oil groove and the internal push rod.

[0024] By adopting the above technical solution, the pressure transmission plate, through the design of connecting the dual oil circuits with the annular oil groove, realizes the synchronous hydraulic drive of the same set of push rods, ensuring the uniformity of circumferential force on the rock sample; the dual oil circuit independent control mode can flexibly adjust the pressure according to the clamping requirements in different directions, further improving the precise control capability of clamping force and ensuring the stable fixation of rock samples with complex shapes.

[0025] Furthermore, the isolation element is vertically arranged circumferentially on the internal push rod to isolate the rock sample from the metal components of the radially centered pressure module.

[0026] By adopting the above technical solution, the circumferentially vertically arranged isolation component forms a physical isolation barrier between the rock sample and the hydraulic system. This not only avoids the cementing material from contaminating the hydraulic oil pipes, push rods and other components, but also prevents hydraulic oil from seeping into the rock sample and affecting the cementing effect and the accuracy of subsequent experimental data. At the same time, the low cost of tin foil makes it easy to replace quickly after the experiment, which greatly improves the cleaning and maintenance efficiency of the device.

[0027] A method for cementing rock samples, characterized in that the rock sample is clamped during cementing treatment using the controllable pressure clamping and impregnation device according to any one of claims 1-5, comprising the following steps:

[0028] S1. Prepare the rock sample and wrap it with gauze; attach the isolation piece to the sample contact plate and pressure transmission plate of the radial centering pressurization module, and at the same time set another layer of circumferentially vertically arranged isolation piece to isolate the rock sample from the metal parts of the radial centering pressurization module; check the sealing of the dual oil circuit hydraulic system; add the bonding material to the cooking pot of the independent heating container, start the heating wire to heat until the bonding material melts and maintain a constant temperature of 50-150℃; connect the manual hydraulic pump to the oil pump pressurization interface;

[0029] S2. Place the wrapped rock sample between the sample contact plates of the radial centering pressurization module; open the control valve corresponding to the radial centering pressurization module, inject oil into hydraulic oil pipe one and hydraulic oil pipe two through the manual hydraulic pump, adjust the pressure to the set value and then lock the control valve.

[0030] S3. Confirm that the rock sample is completely submerged in the molten cementing material; open the control valve corresponding to the radial centering pressurization module, inject oil into the corresponding hydraulic oil pipe through the manual hydraulic pump, adjust the pressure to the set value, and then lock the control valve.

[0031] S4. Maintain pressure under constant temperature and pressure conditions. During this period, monitor the pressure with a high-precision pressure gauge. If the pressure fluctuation exceeds the set range, replenish oil by manually pumping hydraulic oil.

[0032] S5. Open the control valve to release pressure, disconnect the manual hydraulic pump from the oil pump pressurization interface; remove the rock sample to cool and solidify; tear off and replace the isolation piece.

[0033] By adopting the above technical solution, the entire process from sample preparation, clamping and fixing, impregnation and pressure holding to depressurization and cooling, combined with the controllable pressure and constant temperature functions of the device, achieves precise control of constant temperature and pressure during the cementation process. The standardized process not only improves the repeatability of the experiment but also effectively reduces experimental errors through details such as double protection of the isolation components and pressure sealing checks, ensuring the consistency and reliability of the cementation treatment of rock samples.

[0034] Furthermore, the pressure settings in steps S2 and S3 can be set independently or set to the same value; the pressure adjustment accuracy is 0.01 MPa, and the pressure fluctuation during the pressure holding process does not exceed 0.02 MPa.

[0035] By adopting the above technical solution, the independent or synchronous selection mode of pressure setting can flexibly adjust the circumferential pressure according to the texture and fracture development of the rock sample, so as to meet the personalized processing needs of different samples. The pressure adjustment accuracy of 0.01MPa and the pressure holding fluctuation range of 0.02MPa realize ultra-stable pressure control in the cementing process, avoid sample displacement or uneven distribution of cementing material due to pressure fluctuation, and greatly improve the quality and accuracy of cementing treatment.

[0036] Furthermore, in step S1, before attaching the isolation piece, it is necessary to clean the surface impurities of the sample contact plate and pressure transmission plate to ensure that there are no wrinkles or bubbles after the isolation piece is attached; in step S5, after tearing off the isolation piece, a new isolation piece can be directly replaced to process the next set of samples.

[0037] By adopting the above technical solution, the surface cleaning requirements of the sample contact plate and the pressure transmission plate are met, ensuring that the isolation component is bonded without wrinkles or bubbles. This not only improves the uniformity of pressure transmission but also avoids impurities affecting the bonding effect. The operation of directly replacing the isolation component after the experiment simplifies the cleaning process of the device. The next set of experiments can be carried out without complicated cleaning of the contact plate, which significantly improves the experimental processing efficiency.

[0038] Furthermore, in step S1, the temperature of the cementing material is monitored in real time using a thermometer, with a temperature control accuracy of 2℃; in step S4, the holding time is adjusted according to the degree of fracture development of the rock sample, with the holding time for fracture-developed samples being no less than 30 minutes and the holding time for dense samples being 10-20 minutes.

[0039] By adopting the above technical solutions, precise temperature control ensures that the cementing material is always in a stable molten state, avoiding changes in the performance of the cementing material caused by temperature fluctuations. The design of adjusting the holding time according to the degree of fracture development of rock samples, extending the holding time for fracture-developed samples to ensure full penetration of cementing material, and shortening the time for dense samples to improve experimental efficiency, further ensures the sufficiency and effectiveness of cementation treatment.

[0040] Furthermore, in step S1, the hydraulic system sealing check includes observing whether there is oil leakage at the hydraulic oil pipe interface, control valve and high-precision pressure gauge connection; in step S4, if the pressure fluctuation exceeds or falls below 0.02MPa, oil is slowly injected to the set pressure value by manually pumping hydraulic oil, and the relief valve of the hydraulic oil pipe automatically opens to release pressure when the pressure exceeds 2MPa.

[0041] By adopting the above technical solutions, the hydraulic system sealing inspection process can detect pipeline leakage problems in advance, avoiding pressure runaway during the experiment; the design of the relief valve to automatically release pressure when the pressure exceeds 2MPa provides a safety protection barrier for the device, preventing excessive pressure from damaging hydraulic components or crushing rock samples; the pressure replenishment mechanism during the pressure holding process ensures a constant pressure environment during the cementation process, improves the safety and reliability of the device, extends the service life of the equipment, and further ensures the accuracy of experimental data.

[0042] The beneficial effects of this invention are as follows:

[0043] 1. This invention achieves precise control and uniform distribution of the circumferential clamping force of rock samples through a dual-oil-circuit hydraulic drive module and a circumferentially symmetrically arranged multiple sets of internal push rods. This not only avoids sample displacement or breakage due to uneven force, but also allows for flexible adjustment of clamping pressure according to sample texture, greatly improving the stability and adaptability of the cementation process.

[0044] 2. This invention features a detachable sample contact plate and a wide-range pressure adjustment design of 0.1-1MPa. The appropriate contact plate can be replaced according to the shape and size of the rock sample. At the same time, it avoids damage to the sample due to pressure overload while ensuring stable clamping of the sample. This effectively expands the applicability of the device and is especially suitable for processing rock samples with well-developed fractures and brittle texture.

[0045] 3. This invention, through the dual isolation design of the circumferential isolation component and the constant temperature control function of the independent heating container, avoids cross-contamination between the bonding material and the hydraulic system, preventing hydraulic oil from seeping into the sample and affecting the accuracy of experimental data; on the other hand, it achieves precise temperature control of the bonding material, providing a stable temperature environment for the bonding process and improving the consistency and reliability of the bonding effect.

[0046] 4. This invention achieves repeatable operation throughout the entire process from sample preparation, clamping and holding pressure to depressurization and cooling through a standardized constant temperature and pressure bonding process and a high-precision pressure and temperature control mechanism. Combined with real-time pressure fluctuation compensation and safe pressure relief design, it reduces experimental errors, ensures data accuracy, and improves the safety and service life of the device. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0048] Figure 2 This is a top view of the present invention;

[0049] Figure 3 This is a cross-sectional view of the invention along the vertical direction;

[0050] Figure 4 This is a flowchart of the method of the present invention.

[0051] Among them, 1-high precision pressure gauge; 2-hydraulic oil pipe one; 3-control valve; 4-annular hydraulic oil groove; 5-sample; 6-internal push rod; 7-sample contact plate; 8-pressure transmission plate; 9-isolation component; 10-hydraulic oil pipe two; 11-oil pump pressurization interface; 12-thermometer; 13-base; 14-fixing block; 15-heating wire; 16-support block. Detailed Implementation

[0052] The present invention will now be described in further detail with reference to the accompanying drawings and specific preferred embodiments.

[0053] In the description of this invention, it should be understood that the terms "left side," "right side," "upper part," "lower part," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. "First," "second," etc., do not indicate the importance of the components, and therefore should not be construed as a limitation of this invention. The specific dimensions used in this embodiment are only for illustrating the technical solution and do not limit the scope of protection of this invention.

[0054] Reference Figure 1 , Figure 2 , Figure 3 As can be seen, the base 13 serves as the bottom support platform of the entire device, and is equipped with adjustable support feet with an adjustment range of 0-30mm at the bottom. The horizontal stability of the device on different experimental platforms can be ensured by adjusting the height of the support feet. The fixing block 14 is vertically fixed to the center position of the upper surface of the base 13 by welding or bolt fastening. Its top plane provides a flat support surface for the installation of the dual oil circuit hydraulic drive module. The two support blocks 16 are symmetrically fixed to the upper surface of the base 13 with the fixing block 14 as the center and are located on the left and right sides directly below the fixing block 14. The number of support blocks 16 corresponds one-to-one with the internal push rods 6 of the radial centering pressurization module and are evenly arranged circumferentially along the upper surface of the base 13. Each support block 16 has a high-precision guide hole machined inside to provide guidance and constraint for the linear movement of the internal push rods 6.

[0055] The dual-circuit hydraulic drive module is mounted on top of the mounting block 14 of the frame module. The annular hydraulic oil groove 4 is fixed to the upper surface of the mounting block 14 by bolt assembly, serving as a centralized distribution hub for hydraulic oil. One end of hydraulic oil pipe 12 and hydraulic oil pipe 20 are connected to the side wall interface of the annular hydraulic oil groove 4 through flange joints, while the other end is connected to the hydraulic chambers of the two sets of internal push rods 6 in the radial centering pressurization module, respectively, to realize the transmission of hydraulic power. Two control valves 3 are installed in series in the middle section of hydraulic oil pipe 12 and hydraulic oil pipe 20, respectively, which can independently control the on / off of the hydraulic passage and flow regulation of the two sets of internal push rods 6. At least four sets of high-precision pressure gauges 1 are installed at the inlet and outlet positions of hydraulic oil pipe 12 and hydraulic oil pipe 20, respectively, to monitor the inlet and outlet pressure values ​​of each pipeline in real time, providing data support for pressure regulation. The oil pump pressurization interface 11 is located on the upper side wall of the annular hydraulic oil groove 4, and the interface adopts the standard hydraulic pump quick connector specification, which can quickly connect to an external manual or electric hydraulic pump.

[0056] The radial centering pressurization module serves as the core of the device's execution, forming a linked assembly with the frame module and the dual-oil-circuit hydraulic drive module. Four internal push rods 6 are coaxially inserted into the guide holes of the corresponding support blocks 16, with their axes precisely pointing towards the center sample station. The included angles of the axes of adjacent internal push rods 6 are equal, ensuring uniformity of circumferential force. All internal push rods 6 are divided into two groups, each containing two push rods with collinear axes. The two groups of push rods are connected to hydraulic oil pipe 1 2 and hydraulic oil pipe 2 10, respectively, to achieve synchronous and equidistant advancement of the same group of push rods. The inner ends of the internal push rods 6 are fixedly connected to the outer end face of the pressure transmission plate 8 through a flange structure. The inner end face of the pressure transmission plate 8 is fixed with a sample contact plate 7 by a bolt assembly. The plate surface of the sample contact plate 7 is strictly perpendicular to the axis of the corresponding internal push rod 6. The inner end faces of all sample contact plates 7 together form a circumferential clamping space adapted to the shape of the rock sample. Different shapes of sample contact plates 7 can be used to adapt to various rock samples, such as cylindrical and blocky samples.

[0057] An independent heating container, serving as an auxiliary functional module, is placed on the upper surface of the base 13, directly below the central sample station. Its detachable cooking pot is placed directly in the corresponding groove of the base 13. The heating wire 15 is embedded in the heating groove at the bottom of the base 13, providing a stable heat source for the cementing material in the cooking pot through heat conduction. Thermometer 12 is inserted into the pot through a pre-drilled hole in the side wall to monitor the temperature change of the cementing material in real time. The isolation component 9 adopts a double-layer arrangement: one layer adheres to and covers the inner surface of the sample contact plate 7 and pressure transmission plate 8 of the radially centered pressure module, isolating the sample from direct contact with the metal parts; the other layer is vertically arranged in a ring around the inner side of the internal push rod 6, forming an annular barrier around the central sample station, effectively isolating the rock sample from the annular hydraulic oil tank 4 and hydraulic oil pipes, avoiding cross-contamination between the cementing material and the hydraulic oil.

[0058] In one embodiment, the pressure regulation process is centered on a dual-circuit hydraulic drive module. An external hydraulic pump is connected to an annular hydraulic oil tank 4 via an oil pump pressurization interface 11. Hydraulic oil is evenly distributed to hydraulic oil pipe 1 2 and hydraulic oil pipe 2 10 via the annular oil tank. The operator can independently control the oil supply flow of the two sets of internal push rods 6 by adjusting the control valves 3 on hydraulic oil pipe 1 2 and hydraulic oil pipe 2 10. At least four sets of high-precision pressure gauges 1 monitor the inlet and outlet pressure values ​​of the two pipelines in real time, providing accurate data support for pressure regulation. When the pressure reaches the set value... After the value is locked, the internal push rod 6 is pushed by the hydraulic oil and advances synchronously and equidistantly along the guide hole of the support block 16. The pressure is evenly transmitted to the sample contact plate 7 through the pressure transmission plate 8, forming a circumferential symmetrical clamping force on the rock sample in the range of 0.1-1MPa. If the pressure fluctuation shown by the high-precision pressure gauge 1 exceeds 0.02MPa during the pressure holding process, the pressure can be stabilized by manually injecting oil through the hydraulic pump. The overflow valve built into the hydraulic oil pipe will automatically open to release pressure when the pressure exceeds 2MPa to avoid pressure overload damage to the device or sample. The temperature control process is achieved through an independent heating container. After adding the cementing material into the removable pot, the heating wire 15 embedded in the bottom of the base 13 is energized and heats up, heating the cementing material in the pot through heat conduction. A thermometer 12 inserted into the side wall of the pot monitors the temperature of the cementing material in real time. When the temperature reaches the set value of 50-150℃, the output power of the heating wire 15 is adjusted through the temperature control system to maintain a constant temperature of the cementing material. The temperature control accuracy can reach 2℃, providing a stable temperature environment for the cementing and impregnation of rock samples. At the same time, the circumferentially vertically arranged isolation component 9 reduces the transfer of heat to the hydraulic system, preventing the viscosity of the hydraulic oil from being affected by temperature changes, and further ensuring the stability of the pressure regulating system. The entire temperature and pressure regulation process achieves independent control and real-time monitoring of pressure and temperature, ensuring that the rock sample is subjected to uniform stress and has a stable shape during the cementation process, and ensuring that the cementing material is always in the optimal melting state, greatly improving the quality and consistency of the rock sample cementation treatment.

[0059] In one embodiment, the device achieves dual adjustment of height and levelness through adjustable support feet at the bottom of the base 13. The support feet adopt a threaded lifting structure with locking nuts, precisely matching the pre-drilled threaded holes at the four corners of the bottom of the base 13, with an adjustment range of 0-30mm. During adjustment, the operator first places a level on top of the fixed block 14 on the upper surface of the base 13, using this as a reference to observe the tilt direction and degree of the device. Then, the operator rotates the adjustable support feet at the bottom of the base 13 accordingly: when it is necessary to raise the height of one side, rotate the support feet counterclockwise to extend them outward along the threaded holes; when lowering the height, rotate them clockwise to screw them inward. During the process, repeatedly observe the position of the bubble on the level until the bubble is centered and the base 13 is completely level. Afterwards, tighten the locking nut on the top of the support foot to fix the position of the support foot and prevent it from loosening due to vibration or force during the experiment. The core function of this adjustment structure is to ensure that the axis of the internal push rod 6 of the radial centering pressure module is always kept horizontal, so as to avoid the internal push rod 6 generating additional lateral force in the guide hole of the support block 16 due to the tilt of the base, and to ensure that the internal push rod 6 advances synchronously and equidistantly, forming a uniform circumferential symmetrical clamping force on the rock sample. At the same time, the horizontal base 13 can keep the detachable pot of the independent heating container horizontal, prevent the molten cementing material from overflowing due to the tilt of the pot, and ensure that the measuring end of the thermometer 12 is completely immersed in the middle of the cementing material, thereby improving the accuracy of temperature monitoring and the stability of temperature control.

[0060] In one embodiment, firstly, a separator 9 is pre-flattened and attached to the inner surfaces of the sample contact plate 7 and pressure transmission plate 8 of the radially centered pressure module. The separator 9 can be made of insulating foil, which is vertically and circumferentially positioned between the internal push rod 6 and the sample contact plate 7. This prevents the adhesive sample from adhering to the internal push rod 6 and the hydraulic module, thus isolating the rock sample from the metal sample contact plate 7 and pressure transmission plate 8, preventing molten adhesive material from adhering to the metal surface and making it difficult to clean. It also prevents sharp debris from the rock surface from abrading the component surfaces, extending the service life of the device. Simultaneously, another layer of separator 9 is vertically and circumferentially positioned on the inner side of the internal push rod 6, forming a closed annular barrier around the central sample station. This completely separates the rock sample from the annular hydraulic oil tank 4, hydraulic oil pipe 1 2, hydraulic oil pipe 2 10, and the hydraulic chamber of the internal push rod 6, thus preventing... This system prevents the molten cementitious material from splashing or seeping into the hydraulic oil lines and contaminating the hydraulic oil. It also prevents abnormal viscosity and pipe blockage caused by the cementitious material mixing in, and avoids hydraulic oil leakage into the rock sample, thus preventing the hydraulic oil components from interfering with the penetration effect of the cementitious material and the accuracy of subsequent experimental data. Furthermore, during the rock sample preparation stage, the rock sample is first wrapped in gauze to form a pre-protective layer, further reducing damage caused by direct contact between rock debris and the isolator 9, while also reducing the impact of impurities on the surface of the rock sample from direct contact with the cementitious material. After the experiment, simply remove the used isolator 9 and replace it with a new one to conduct the next set of experiments. There is no need for complex cleaning of components such as the sample contact plate 7 and pressure transmission plate 8, which simplifies the device cleaning process and effectively avoids cross-contamination between different batches of samples, ensuring the reliability of experimental results and the continuous stable operation of the device.

[0061] Reference Figure 4 It is understood that the present invention further discloses a method for cementing rock samples, characterized in that the rock sample is clamped during the cementing process using a controllable pressure clamping impregnation device, comprising the following steps:

[0062] S1. Prepare a rock sample and wrap it with gauze; attach an isolation piece 9 to the surface of the sample contact plate 7 and pressure transmission plate 8 of the radial centering pressure module, and at the same time set another layer of circumferentially vertically arranged isolation pieces 9 to isolate the rock sample from the metal parts of the radial centering pressure module; check the sealing of the dual oil circuit hydraulic system; add a bonding material to the cooking pot of the independent heating container, start the heating wire 15 to heat until the bonding material melts and maintain a constant temperature of 50-150℃; connect the manual hydraulic pump to the oil pump pressure interface 11;

[0063] S2. Place the wrapped rock sample between the sample contact plates 7 of the radial centering pressure module; open the control valve 3 corresponding to the radial centering pressure module, inject oil into the hydraulic oil pipe 1 2 and the hydraulic oil pipe 2 10 through the manual hydraulic pump, adjust the circumferential clamping pressure to the first set value, and then lock the control valve 3.

[0064] S3. Adjust the relative position of the rock sample and the independent heating container to ensure that the rock sample is completely immersed in the molten cementing material; open the control valve 3 corresponding to the radial centering pressure module, inject oil into the corresponding hydraulic oil pipe through the manual hydraulic pump, adjust the pressure holding pressure to the second set value, and then lock the control valve 3.

[0065] S4. Maintain pressure under constant temperature and pressure conditions. During this period, the system pressure is monitored in real time by a high-precision pressure gauge 1. If the pressure fluctuation exceeds the set range, oil is added manually by a hydraulic pump to stabilize the pressure.

[0066] S5. Slowly open control valve 3 to release pressure, disconnect the manual hydraulic pump from the oil pump pressurization interface 11; remove the rock sample and let it stand to cool until the cementing material is completely cured; tear off the used isolation piece 9 and replace it with a new isolation piece 9.

[0067] In step S2 and step S3, the pressure settings can be set independently or set to the same value; the pressure adjustment accuracy is 0.01MPa, and the pressure fluctuation during the pressure holding process does not exceed ±0.02MPa.

[0068] In step S1, before attaching the isolation piece 9, the surface impurities of the sample contact plate 7 and pressure transmission plate 8 need to be cleaned to ensure that there are no wrinkles or bubbles after the isolation piece 9 is attached; in step S5, after tearing off the isolation piece 9, a new isolation piece 9 can be directly replaced to process the next set of samples.

[0069] In step S1, the temperature of the cementing material is monitored in real time by thermometer 12, with a temperature control accuracy of 2℃; in step S4, the holding time is adjusted according to the degree of fracture development of the rock sample. The holding time for fracture-developed samples is not less than 30 minutes, and the holding time for dense samples is 10-20 minutes.

[0070] In step S1, the hydraulic system sealing check includes observing whether there is oil leakage at the connection points of the hydraulic oil pipe interface, control valve 3 and high-precision pressure gauge 1; in step S4, if the pressure fluctuation exceeds or falls below 0.02MPa, oil is slowly injected to the set pressure value using a manual hydraulic pump, and the relief valve of the hydraulic oil pipe automatically opens to release pressure when the pressure exceeds 2MPa.

[0071] In one embodiment, in step S1, the rock sample is first cut and polished to a suitable size according to the clamping space formed by the sample contact plates 7 in the radial centering pressurization module. Then, the rock sample is tightly wrapped with clean gauze to avoid direct wear of the isolation piece 9 by sharp debris on the rock surface and to reduce interference from impurities during the penetration of the adhesive material. Next, the cut isolation piece 9 is taken and flattened onto the inner end face of all sample contact plates 7 and the inner surface of the pressure transmission plate 8 to ensure complete coverage of the contact area between the metal parts and the sample. Next, another isolating piece 9 is arranged vertically along the inner side of the internal push rod 6 to form a closed annular barrier around the central sample station, completely isolating the rock sample from the annular hydraulic oil tank 4, hydraulic oil pipe 1 2, hydraulic oil pipe 2 10 and other hydraulic system components; then, a sealing check of the dual-circuit hydraulic system is carried out: the temporary hydraulic source is connected to the oil pump pressurization interface 11 through a quick connector, the control valves 3 on hydraulic oil pipe 1 2 and hydraulic oil pipe 2 10 are opened, the pressure is slowly increased to 0.5MPa and then the control valves 3 are closed, and the inlet and outlet of the corresponding hydraulic oil pipes are observed. While monitoring the change in the value of the high-precision pressure gauge 1 at the inlet, simultaneously check for hydraulic oil leakage at the annular hydraulic oil groove 4, hydraulic oil pipe interface, and the connection between the internal push rod 6 and the guide hole of the support block 16. If the value of the high-precision pressure gauge 1 does not decrease significantly and there is no leakage within 10 minutes, the sealing is qualified. Then, depressurize and disconnect the temporary hydraulic source. Afterward, add sufficient binding material, such as rosin-paraffin mixture, low melting point hot melt adhesive, etc., to the removable cooking pot of the independent heating container. Insert the thermometer 12 through the reserved hole on the side wall of the cooking pot and ensure that the measuring end is immersed. Submerged in the middle of the adhesive material, the heating wire 15 embedded in the bottom of the base 13 is activated, and the heating power is adjusted through the temperature control system. When the temperature displayed by the thermometer 12 reaches the preset value of 50-150℃, the heating power is maintained to keep the temperature constant. During this period, the adhesive material can be gently stirred with a stirring rod to ensure uniform melting. Finally, the standard quick connector of the manual hydraulic pump is precisely connected to the oil pump pressurization interface 11 on the annular hydraulic oil tank 4, and the connector locking mechanism is tightened to ensure that the connection is firm and not loose, in preparation for the subsequent pressure adjustment of the radial centering pressurization module.

[0072] In one embodiment, in step S2, firstly, it is confirmed that the internal push rod 6 of the radial centering pressurization module is in the initial retracted state. The rock sample wrapped in gauze is then placed stably in the central position formed by at least four sets of sample contact plates 7. The sample position is adjusted so that the distance between it and each sample contact plate 7 is uniform, ensuring symmetrical force during subsequent pressurization. Then, the corresponding control valves 3 on hydraulic oil pipe 1 2 and hydraulic oil pipe 2 10 are opened, so that the annular hydraulic oil groove 4 and the two hydraulic oil pipes form a connected circuit. Next, the manual hydraulic pump connected to the oil pump pressurization interface 11 is operated, and the pump body pressure rod is repeatedly pressed to inject hydraulic oil into the annular hydraulic oil groove 4. The hydraulic oil is evenly distributed to hydraulic oil pipe 1 2 and hydraulic oil pipe 2 10 through the annular oil groove, pushing the two sets of internal push rods 6 to advance synchronously and equidistantly along the guide holes of the support block 16, thereby driving the sample contact plates 7 to advance one by one. Gradually approach the rock sample; during the advancement process, observe the changes in the values ​​of at least four sets of high-precision pressure gauges 1 in real time to ensure that the inlet and outlet pressures of hydraulic oil pipe 1 2 and hydraulic oil pipe 2 10 remain balanced. When the pressure shown by high-precision pressure gauge 1 reaches the experimentally set range of 0.1-1MPa, stop pressing the manual hydraulic pump and immediately tighten the control valve 3 on hydraulic oil pipe 1 2 and hydraulic oil pipe 2 10 clockwise to cut off the flow path of hydraulic oil and maintain pressure stability. In the initial stage of pressure holding, it is necessary to continuously observe the high-precision pressure gauge 11-2 minutes. If the pressure fluctuation exceeds 0.02MPa, the control valve 3 can be briefly loosened to replenish oil to the set pressure through the manual hydraulic pump and then tightened again. At the same time, the overflow valve built into the device will automatically open to release pressure when the pressure unexpectedly exceeds 2MPa, effectively avoiding pressure overload damage to the device or deformation of the rock sample.

[0073] In one embodiment, in step S3, the independent heating container is moved directly below the central sample station, and the rock sample is slowly lowered into the boiling pot. The rock sample is confirmed to be completely submerged in the molten cementing material through the transparent observation window on the side wall of the boiling pot. If the liquid level is insufficient, preheated cementing material is immediately added. Simultaneously, the heating wire 15 at the bottom of the base 13 is kept continuously working to maintain a constant temperature of 50-150°C as displayed by the thermometer 12, preventing incomplete submersion due to the cementing material solidifying from a sudden temperature drop. Then, the quick connector of the manual hydraulic pump is switched to the oil pump pressurization interface 11 corresponding to the radial centering pressurization module. The control valve 3 of the hydraulic oil pipe is opened, and the manual hydraulic pump lever is repeatedly pressed to inject oil into the hydraulic oil pipe. The hydraulic oil pushes the internal propulsion rod 6 smoothly along the guide hole of the support block 16, causing the pressure transmission plate 8 to contact the sample contact plate 7. Apply uniform pressure to the upper and lower surfaces of the rock sample. Monitor the changes in the value of the high-precision pressure gauge 1 on the hydraulic oil pipe in real time during the advancement process. When the pressure reaches the experimentally set range of 0.05-0.5MPa, stop pressing the hydraulic pump and immediately tighten the control valve 3 of the hydraulic oil pipe clockwise to lock the pressure. During the initial pressure holding period, continuously observe the high-precision pressure gauge 1 for 1-2 minutes. If the pressure fluctuation exceeds 0.01MPa, the control valve 3 can be loosened briefly to replenish oil to the set pressure and then tightened again. At the same time, the overflow valve built into the device will automatically open to release pressure when the pressure unexpectedly exceeds 1MPa, effectively preventing the rock sample from breaking or the molten cementing material from being squeezed out due to pressure overload. This ensures that the rock sample is uniformly penetrated and wrapped by the molten cementing material under a circumferentially stable pressure environment, further enhancing the physical isolation effect between the rock sample and the various components of the device.

[0074] In one embodiment, in step S4, after completing the circumferential pressure application and locking the corresponding control valve 3, the device enters the constant temperature and pressure holding stage. At this time, the heating wire 15 at the bottom of the independent heating container base 13 continues to work, and the heating power is automatically adjusted by the temperature control system to maintain a constant temperature of 50-150℃ as displayed by the thermometer 12 in the cooking pot, ensuring that the molten cementing material always maintains a fluid dynamic to fully penetrate the rock sample. At the same time, the high-precision pressure gauge 1 on the circumferential hydraulic oil pipe monitors the system pressure in real time. The experimenter needs to record the pressure value every 15-30 minutes. When the circumferential pressure fluctuation exceeds ±0.02MPa or the pressure fluctuation exceeds ±0.01MPa, the corresponding pressure circuit should be located immediately. If the circumferential pressure drops, the control valves 3 of the circumferential hydraulic oil pipe 1 2 and the hydraulic oil pipe 2 10 should be opened slowly first, and the manual hydraulic pump should be connected to the circumferential oil pump pressurization interface 11. Repeatedly press the pump body lever to replenish oil until the high-precision pressure gauge 1 displays a value that returns to the set value. Then, tighten the control valve 3 clockwise to lock the pressure. If the pressure drops, switch the manual hydraulic pump to the oil pump pressurization port 11, open the control valve 3 of the hydraulic oil pipe to replenish oil to the set pressure, and then lock it. During the pressure holding period, the integrity of the isolation component 9 must be checked simultaneously. If local damage is found that causes leakage of the cementing material, the pressure holding must be stopped immediately, a new isolation component 9 must be replaced, and the pressure and temperature must be readjusted. Throughout the process, the built-in overflow valve of the device will continuously monitor the system pressure. When the pressure unexpectedly exceeds the safety threshold, it will automatically open to release pressure, effectively preventing pressure overload from damaging the rock sample or device components. This ensures that the cementing material and the rock sample are fully bonded in a stable constant temperature and pressure environment. At the same time, through the continuous isolation effect of the isolation component 9, the cementing material is prevented from sticking to the device components or contaminating the hydraulic system.

[0075] In one embodiment, in step S5, after the pressure holding stage, the control valves 3 on the first and second hydraulic oil pipes 10 of the radial centering pressurization module are slowly opened to allow the hydraulic oil in the annular hydraulic oil groove 4 to slowly flow back to the manual hydraulic pump's oil storage chamber through the pipeline. After the value of the circumferential high-precision pressure gauge 1 drops to 0 MPa, the control valve 3 of the corresponding hydraulic oil pipe of the radial centering pressurization module is opened to complete the pressure relief. Throughout the process, rapid valve opening is avoided to prevent a sudden drop in pressure that could cause the rock sample and cementing material to separate. After the pressure relief is completed, the quick-connect locking mechanism of the manual hydraulic pump and the oil pump pressurization interface 11 is loosened first. After confirming that there is no residual pressure, the connection is disconnected, and the manual hydraulic pump is moved to the designated storage location. Then, the reset device of the radial centering pressurization module is operated to drive the internal push rod 6. The moving sample contact plate 7 retracts outward, while the pressure transmission plate 8 of the radially centered pressure module rises, exposing the rock sample at the center position. The rock sample wrapped in gauze is carefully removed using a high-temperature resistant clamp and placed on a ventilated and heat-insulated platform. It is left to stand at room temperature for 2-4 hours or placed in a low-temperature curing chamber to cool until the adhesive material is completely cured. Finally, the old isolation pieces 9, which are vertically arranged around the sample contact plate 7, the pressure transmission plate 8, and the circumferentially arranged, are removed. The remaining adhesive material debris on the metal contact surface is wiped off with a lint-free cloth dampened with a small amount of anhydrous ethanol. The new isolation pieces 9 are then flatly attached to the inner end face of the sample contact plate 7 and the inner surface of the pressure transmission plate 8. The circumferentially arranged vertical isolation pieces 9 are then reset to ensure complete coverage of all metal parts in contact with the sample, preparing for the next experiment.

[0076] Working Principle: This device uses a manual hydraulic pump as its power core. Hydraulic oil is injected into hydraulic oil pipes 1-2 and 2-10 through the oil pump pressurization interface 11. The annular hydraulic oil groove 4 evenly distributes the hydraulic oil into the drive chambers of at least four sets of internal push rods 6, pushing the internal push rods 6 synchronously and equidistantly along the guide holes of the support block 16. This drives the sample contact plate 7 to apply circumferential pressure to the rock sample at the center position. The high-precision pressure gauge 1 monitors the inlet and outlet pressures of hydraulic oil pipes 1-2 and 2-10 in real time to ensure that the circumferential force deviation is controlled within 0.02MPa. At the same time, the independent heating container maintains the molten state through the heating wire 15. The cementing material is kept at a constant temperature of 50-150℃, and the thermometer 12 provides real-time temperature feedback to ensure the stability of the cementing material's fluidity. The radial centering pressurization module drives the internal push rod 6 through another set of hydraulic oil pipes to apply pressure to the sample via the pressure transmission plate 8. The isolator 9 isolates the rock sample, cementing material, and metal parts throughout the process to prevent adhesion. If the high-precision pressure gauge 1 shows that the pressure fluctuation exceeds the threshold during the pressure holding stage, oil can be added manually via the hydraulic pump. The overflow valve automatically releases pressure when the pressure exceeds 2MPa, ultimately achieving the experimental objective of fully penetrating and encapsulating the rock sample with the molten cementing material under a constant temperature and multi-directional uniform pressure environment.

[0077] This device uses an annular hydraulic oil groove 4 to evenly distribute hydraulic oil to at least four sets of internal push rods 6, driving the sample contact plate 7 to advance synchronously and at equal intervals, so that the circumferential force deviation of the rock sample is controlled within 0.02MPa, completely solving the problem of sample deformation caused by uneven pressure.

[0078] The sample contact plate 7, pressure transmission plate 8 and circumferential isolation component 9 are set. Taking advantage of its high temperature resistance and non-stick properties, the rock sample, molten cementing material and metal parts are effectively isolated. After the experiment, it can be directly torn off and replaced, completely avoiding the difficulty of cleaning the device caused by the adhesion of cementing material.

[0079] The independent heating container is equipped with a closed-loop temperature control system consisting of heating wire 15 and thermometer 12, which controls the temperature fluctuation within 2℃, ensuring that the molten cementing material always maintains stable fluidity and solving the problem of insufficient cementing penetration caused by unstable temperature.

[0080] At least four sets of high-precision pressure gauges are used to monitor the circumferential and hydraulic circuit pressure in real time. Combined with the precise pressure replenishment of the manual hydraulic pump and the automatic pressure relief function of the relief valve, the pressure fluctuation is controlled within 0.01MPa of the set value, which greatly reduces the error of experimental data. At the same time, the modular design of the device facilitates quick disassembly and maintenance, further improving the convenience and reliability of experimental operation.

[0081] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A controllable pressure clamping and impregnation device for cementation treatment of rock samples, characterized in that, include: The frame module comprises a dual-oil-circuit hydraulic drive module, a radial centering pressurization module, an independent heating container, and an isolator (9). The dual-oil-circuit hydraulic drive module is mounted on the frame module and is used to provide installation support for each module. The dual-oil-circuit hydraulic drive module is connected to the radial centering pressurization module to adjust the clamping force of the radial centering pressurization module on the rock sample. The independent heating container is located on the frame module, and the radial centering pressurization module is used to clamp the rock sample. The isolator (9) is provided between the radial centering pressurization module and the rock sample.

2. The controllable pressure clamping and impregnation device for cementation treatment of rock samples according to claim 1, characterized in that, The frame module includes a base (13), a fixing block (14), and a support block (16); the fixing block (14) is vertically fixed to the center of the upper surface of the base (13), and the support block (16) is symmetrically fixed to the upper surface of the base (13) and located on the left and right sides of the fixing block (14); the bottom of the base (13) is provided with adjustable support feet with an adjustment range of 0-30mm; The dual-circuit hydraulic drive module includes an annular hydraulic oil tank (4), hydraulic oil pipe one (2), hydraulic oil pipe two (10), control valves (3), high-precision pressure gauges (1), and oil pump pressurization interface (11). The annular hydraulic oil tank (4) is installed on the top of the fixed block (14). One end of hydraulic oil pipe one (2) and hydraulic oil pipe two (10) are connected to the annular hydraulic oil tank (4), and the other end is connected to the radial centering pressurization module. The two control valves (3) are respectively set on hydraulic oil pipe one (2) and hydraulic oil pipe two (10). At least four sets of high-precision pressure gauges (1) are respectively set at the inlet and outlet of hydraulic oil pipe one (2) and hydraulic oil pipe two (10). The oil pump pressurization interface (11) is set on the annular hydraulic oil tank (4), and the interface is adapted to a standard hydraulic pump quick connector. The radial centering pressurization module includes at least four internal push rods (6), a corresponding number of pressure transmission plates (8), and a sample contact plate (7). The number of the support blocks (16) corresponds to the number of the internal push rods (6), and they are evenly arranged circumferentially along the upper surface of the base (13); each of the internal push rods (6) is coaxially installed in the guide hole of the corresponding support block (16), with the axis pointing to the central sample station, and the included angle of the axes of adjacent push rods is equal; The pressure transmission plate (8) is disposed between the internal push rod (6) and the sample contact plate (7). The inner end of the internal push rod (6) is fixedly connected to the outer end face of the pressure transmission plate (8) through a flange structure. The sample contact plate (7) is fixed to the inner end face of the pressure transmission plate (8) by a bolt assembly, and the plate surface of the sample contact plate (7) is perpendicular to the axis of the corresponding internal push rod (6). The inner end faces of all the sample contact plates (7) together enclose a circumferential clamping space adapted to the shape of the rock sample. The internal push rod (6) is divided into at least two groups, each group containing two push rods arranged opposite each other. Each group of internal push rods (6) is connected to a hydraulic control pipeline to realize synchronous or independent pressurization of the rock sample. The first hydraulic oil pipe (2) and the second hydraulic oil pipe (10) are respectively connected to the annular hydraulic oil groove (4). The internal push rod (6) synchronously receives hydraulic driving force to realize circumferential synchronous equidistant advancement and form a uniformly distributed circumferential symmetrical clamping force on the rock sample. The independent heating container is placed on the upper surface of the base (13) and located directly below the central sample station. It includes a removable cooking pot, a heating wire (15) and a thermometer (12). The heating wire (15) is embedded in the bottom heating groove of the base (13), and the thermometer (12) is inserted into the pot through a reserved hole on the side wall of the cooking pot, with the measuring end immersed in the adhesive material.

3. The controllable pressure clamping and impregnation device for cementation treatment of rock samples according to claim 1, characterized in that, The sample contact plate (7) of the radial centering pressurization module is a detachable structure and is connected to the internal push rod (6) through the pressure transmission plate (8); the synchronous push pressure range of the internal push rod (6) is 0.1-1MPa.

4. The controllable pressure clamping and impregnation device for cementing treatment of rock samples according to claim 1, characterized in that, The hydraulic oil pipe one (2) and hydraulic oil pipe two (10) respectively deliver hydraulic oil to the hydraulic chambers of the corresponding two sets of internal push rods (6), pushing the internal push rods (6) to move in the direction of approaching or moving away from the rock sample, thereby driving the pressure transmission plate (8) and the sample contact plate (7) to clamp or release the rock sample; the hydraulic oil pipe one (2) and hydraulic oil pipe two (10) respectively connect the annular hydraulic oil groove (4) and the hydraulic chamber of the corresponding internal push rod (6).

5. The controllable pressure clamping and impregnation device for cementation treatment of rock samples according to claim 1, characterized in that, The isolation element (9) is vertically arranged circumferentially on the internal push rod (6) to isolate the rock sample from the metal parts of the radially centered pressurizing module.

6. A method for cementing rock samples, characterized in that, The controllable pressure clamping and impregnation device according to any one of claims 1-5 is used to clamp rock samples during cementation treatment, including the following steps: S1. Prepare a rock sample and wrap it with gauze; attach an isolation piece (9) to the sample contact plate (7) and pressure transmission plate (8) of the radial centering pressure module, and set another layer of circumferentially vertically arranged isolation piece (9) to isolate the rock sample from the metal parts (4) of the radial centering pressure module; check the sealing of the dual oil circuit hydraulic system; add the bonding material to the pot of the independent heating container, start the heating wire (15) to heat until the bonding material melts and maintains a constant temperature of 50-150℃; connect the manual hydraulic pump to the oil pump pressure interface (11); S2. Confirm that the rock sample is completely submerged in the molten cementitious material; S3. Place the wrapped rock sample between the sample contact plates (7) of the radial centering pressurization module; open the control valve (3) corresponding to the radial centering pressurization module, inject oil into the hydraulic oil pipe one (2) and the hydraulic oil pipe two (10) by manual hydraulic pump, adjust the pressure to the set value and then lock the control valve (3). S4. Maintain pressure under constant temperature and pressure conditions. During this period, monitor the pressure using a high-precision pressure gauge (1). If the pressure fluctuation exceeds the set range, replenish oil using a manual hydraulic pump. S5. Open the control valve (3) to release pressure, disconnect the manual hydraulic pump from the oil pump pressurization interface (11); take out the rock sample to cool and solidify; tear off and replace the isolation piece (9).

7. The method for cementing rock samples according to claim 6, characterized in that, In step S2 and step S3, the pressure setting values ​​can be set independently or set to the same value; the pressure adjustment accuracy is 0.01MPa, and the pressure fluctuation during the pressure holding process does not exceed 0.02MPa.

8. The method for cementing rock samples according to claim 6, characterized in that, In step S1, before attaching the isolation piece (9), the surface impurities of the sample contact plate (7) and pressure transmission plate (8) need to be cleaned to ensure that the isolation piece (9) is wrinkle-free and bubble-free after attachment; in step S5, after removing the isolation piece (9), a new isolation piece (9) can be directly replaced to process the next set of samples.

9. The method for cementing rock samples according to claim 6, characterized in that, In step S1, the temperature of the cementing material is monitored in real time by a thermometer (12), and the temperature control accuracy is 2℃. In step S4, the holding time is adjusted according to the degree of crack development of the rock sample. The holding time of the crack-developed sample is not less than 30 minutes, and the holding time of the dense sample is 10-20 minutes.

10. The method for cementing rock samples according to claim 6, characterized in that, In step S1, the hydraulic system sealing check includes observing whether there is oil leakage at the connection of the hydraulic oil pipe interface, control valve (3) and high-precision pressure gauge (1); in step S4, if the pressure fluctuation exceeds or falls below 0.02MPa, oil is slowly injected to the set pressure value by manually pumping hydraulic oil, and the overflow valve of the hydraulic oil pipe automatically opens to release pressure when the pressure exceeds 2MPa.

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