A high-temperature and high-pressure experimental device, experimental system and experimental method

Abstract

The present invention relates to the experimental technical field of geological samples, and provides a high-temperature and high-pressure experimental device, an experimental system and an experimental method. The high-temperature and high-pressure experimental device includes a machine shell and a triaxial pressure assembly. The triaxial pressure assembly includes an axial pressure component and a protective sleeve. A main cavity is provided inside the machine shell, and at least part of the axial pressure component is embedded in the main cavity. The axial pressure component includes a first pressing head, a first mounting seat, a second mounting seat, a second pressing head and a pressure loading structure which are arranged and distributed in sequence along the axial direction of the machine shell. A sample chamber is formed between the first mounting seat and the second mounting seat, and a sample is installed in the sample chamber. The protective sleeve is sleeved on parts of the first pressing head and the second pressing head, as well as the first mounting seat, the sample and the second mounting seat. The present invention can not only be applicable to the triaxial experiment of small samples, but also be applicable to the triaxial experiment of standard-size samples, thereby expanding the application range of the high-temperature and high-pressure experimental device.

Description

Technical Field

[0001] The present invention relates to the experimental technical field of geological samples, and in particular, to a high-temperature and high-pressure experimental device, an experimental system and an experimental method. Background Art

[0002] At present, in the prior art, high-temperature and high-pressure experimental devices are mainly used to apply pressure to samples, such as geological samples, in three coordinate directions of space under high-temperature and high-pressure environments to conduct triaxial experiments to measure the mechanical data of the samples. For example, the mechanical data mainly includes axial pressure data, confining pressure data, pore pressure data, etc. Among them, the geological sample is usually a standard-size sample (i.e., a cylindrical sample with a diameter-to-height ratio of 0.5-1), such as a diameter of 20 mm and a height of 40 mm. The high-temperature and high-pressure experimental device mainly includes a casing and an axial pressure assembly arranged inside the casing. A sample chamber for placing the sample is provided in the middle of the axial pressure assembly. When conducting axial pressure tests, the high-temperature and high-pressure experimental device needs to be placed at a uniaxial press, so that the top and bottom ends of the axial pressure assembly are respectively abutted against the frame and the telescopic rod of the uniaxial press, and the uniaxial press applies a force to the axial pressure assembly to measure the axial pressure data of the above standard-size sample.

[0003] However, for some small samples such as drilling cuttings, planetary samples, etc., these small samples are precious in source, small in quantity and volume, and irregular in shape. Therefore, the aspect ratio of the samples prepared for the experiment varies greatly, such as a diameter of 8 mm and a height that can be 5-20 mm. In addition, in order to avoid damage to the pressure loading system caused by external heating, the length of the sample loading system is inevitably increased. When the uniaxial press applies axial pressure to the small sample through the axial pressure assembly, the small sample is prone to accidents such as bending and tilting. Therefore, the above high-temperature and high-pressure experimental device for conducting triaxial experiments on standard-size samples cannot conduct triaxial experiments on such small samples, which in turn limits the application range of the high-temperature and high-pressure experimental device. Summary of the Invention

[0004] The problem solved by the present invention is how to expand the application range of a high-temperature and high-pressure experimental device for conducting triaxial experiments on samples.

[0005] To solve the above problems, in the first aspect, the present invention provides a high-temperature and high-pressure experimental device, including a casing and a triaxial pressure assembly. The triaxial pressure assembly includes an axial pressure component and a protective sleeve. A main cavity is provided inside the casing, and at least part of the axial pressure component is embedded in the main cavity.

[0006] The axial pressure component includes a first pressing head, a first mounting seat, a second mounting seat, a second pressing head and a pressure loading structure arranged in sequence along the axial direction of the casing. A sample chamber is formed between the first mounting seat and the second mounting seat, and the sample chamber is used for installing the sample.

[0007] The part of the protective sleeve sleeved on the first pressing head and the second pressing head, as well as the first mounting seat, the sample and the second mounting seat.

[0008] Optionally, the triaxial pressure assembly further includes a third pressing head and a fixing sleeve. The third pressing head is embedded in the main cavity, and the third pressing head is slidably sleeved on the pressure loading structure.

[0009] The pressure loading structure includes a pressure loading rod and an annular protrusion arranged coaxially. The annular protrusion is fixedly sleeved on the outer circumferential wall of the pressure loading rod. The interior of the third pressing head is provided with a first cavity and a second cavity that are sequentially communicated along the axial direction of the pressure loading rod. The fixing sleeve is slidably embedded in the first cavity, and the fixing sleeve is sleeved on the second pressing head and the top end of the pressure loading rod; the annular protrusion is slidably arranged in the second cavity.

[0010] Optionally, a confining pressure cavity is formed between the protective sleeve and the inner wall of the machine shell.

[0011] The triaxial pressure assembly further includes a heating furnace and two heat conducting sleeves. The machine shell is of a convex structure, and the convex structure surrounds the sample chamber. The heating furnace is sleeved on the narrow part of the convex structure for heating the confining pressure fluid in the confining pressure cavity.

[0012] The two heat conducting sleeves are arranged at intervals along the axial direction of the machine shell, and the heat conducting sleeves are sleeved outside the protective sleeve, and the two heat conducting sleeves respectively wrap the joints between the sample and the first mounting seat and between the sample and the second mounting seat.

[0013] A first channel for the confining pressure fluid to flow through is formed between the heat conducting sleeve and the inner wall of the machine shell, and / or a second channel for the confining pressure fluid to flow through is formed between the heat conducting sleeve and the protective sleeve.

[0014] Optionally, the triaxial pressure assembly further includes two heat insulation sleeves. The two heat insulation sleeves are arranged at intervals along the axial direction of the machine shell. The heat insulation sleeves are sleeved outside the protective sleeve, and the two heat conducting sleeves are located between the two heat insulation sleeves.

[0015] A third channel for the confining pressure fluid to flow through is formed between the heat insulation sleeve and the inner wall of the machine shell, and / or a fourth channel for the confining pressure fluid to flow through is formed between the heat insulation sleeve and the protective sleeve.

[0016] Optionally, the triaxial pressure assembly further includes a thermocouple. Installation grooves are provided on the inner walls of the heat insulation sleeve and the heat conduction sleeve. One end of the thermocouple is outside the first indenter, and the other end of the thermocouple sequentially passes through the first indenter and the installation grooves of the heat insulation sleeve and the heat conduction sleeve and extends to the sample chamber.

[0017] Optionally, the triaxial pressure assembly further includes a heat insulation ring. The heat insulation ring is sleeved outside the protective sleeve, and the heat insulation ring is located between the heat insulation sleeve and the first indenter.

[0018] Optionally, the triaxial pressure assembly further includes a first sealing ring, a second sealing ring and a detection device. The first sealing ring is embedded between the fixed sleeve and the pressure loading rod, and the second sealing ring is embedded between the fixed sleeve and the third indenter;

[0019] A third cavity is formed between the annular protrusion and the fixed sleeve. The third indenter is further provided with a first flow channel and a second flow channel that communicate with each other. The second flow channel communicates with the third cavity through the first flow channel. The detection device communicates with the second flow channel and is used to detect whether the confining pressure fluid in the confining pressure chamber leaks at the first sealing ring and the second sealing ring, and the exhaust pressure of the air in the third cavity from the second flow channel.

[0020] Compared with the prior art, when the present invention performs axial pressure testing in a triaxial experiment on a sample, such as a small sample, the top and bottom ends of the axial pressure assembly, such as the first indenter and the pressure loading structure, can be respectively abutted against the fixed frame and the telescopic rod of the press. The press applies an axial pressure to the axial pressure assembly and acts on the small sample to achieve axial pressure testing of the small sample; during the axial pressure testing process, since the protective sleeve is sleeved on the lower part of the first indenter and the upper part of the second indenter, as well as the first mounting seat, the sample and the second mounting seat. In other words, the protective sleeve always fixes the first indenter and the second indenter, as well as the first mounting seat, the sample and the second mounting seat on the same vertical axis, which can play a positioning role for the sample and effectively prevent the sample from being bent or offset during the axial pressure testing process, so as to ensure the normal operation of the axial pressure testing operation. It can not only be applied to triaxial experiments of small samples, but also to triaxial experiments of standard-sized samples, thereby expanding the application range of the high-temperature and high-pressure experimental device, and can also effectively prevent the confining pressure fluid from directly entering the sample during the subsequent confining pressure testing, thus interfering with the subsequent pore pressure testing of the sample.

[0021] Furthermore, since the protective sleeve is only sleeved on the lower part of the first punch and the upper part of the second punch, in other words, there is a certain interval reserved between the top end of the protective sleeve and the top end of the first punch and between the bottom end of the protective sleeve and the bottom end of the second punch. This interval can be used as the deformation distance of the sample when the press applies axial pressure to the axial compression assembly. For example, during axial compression testing, the sample is compressed and shortened, and the distance between the first punch and the second punch becomes smaller. During this process, since the intervals reserved at the top and bottom ends of the protective sleeve do not interfere with the axial compression test operation of the press on the sample through the axial compression assembly until the axial compression test ends, there is a small interval or they are in contact between the top and bottom ends of the protective sleeve and the first and second punches respectively, thus ensuring the smooth progress of the axial compression test.

[0022] In addition, the first punch, the first mounting seat, the second mounting seat, the second punch, and the pressure loading structure can be in a split form, such as detachable connection, so that not only is it convenient to load and unload the sample, but also during the process of taking out the sample, it is possible to avoid the longer second punch and the pressure loading structure from breaking, correspondingly reducing the maintenance frequency and extending its service life.

[0023] In a second aspect, another embodiment of the present invention provides an experimental system, including the high-temperature and high-pressure experimental device as described above, and further including a press, the press including a frame and a telescopic rod, and the opposite ends of the axial compression assembly in the high-temperature and high-pressure experimental device are respectively correspondingly connected to the frame and the telescopic rod.

[0024] Since the experimental system includes the high-temperature and high-pressure experimental device, the experimental system at least has all the technical effects of the high-temperature and high-pressure experimental device, which will not be elaborated here.

[0025] In a third aspect, another embodiment of the present invention provides an experimental method, based on the experimental system as described above, including the following steps:

[0026] Process the selected blank material to form a sample that meets the experimental requirements;

[0027] Assemble the sample and the axial compression assembly in the casing of the high-temperature and high-pressure experimental device;

[0028] Apply axial pressure to the axial compression assembly through the press to conduct an axial compression experiment, and collect the first axial compression data in real time;

[0029] Control the confining pressure device of the experimental system to fill the confining pressure fluid into the confining pressure chamber where the sample is located and the compensation chamber of the triaxial pressure assembly, so that the triaxial pressure assembly is in a hydrostatic state;

[0030] Control the pore pressure device to input pore fluid into the sample, increase the flow rate of the confining pressure fluid multiple times, apply axial pressure to the axial compression assembly multiple times, and collect and record the mechanical data of the sample;

[0031] Save the mechanical data, unload the axial pressure, the confining pressure fluid and the pore fluid, disassemble the triaxial pressure assembly, and take out the sample.

[0032] Since the experimental method is based on the experimental system described above, the experimental method at least has all the technical effects of the experimental system, which will not be elaborated here.

[0033] Optionally, the processing of the selected blank to form a sample meeting the experimental requirements includes:

[0034] Select a blank meeting the experimental requirements;

[0035] Fix and repair the blank with a gum substance;

[0036] Grind the repaired blank to form a sample meeting the experimental requirements. Description of the Drawings

[0037] Figure 1 It is a schematic cross-sectional structure diagram of the high-temperature and high-pressure experimental device in the embodiment of the present invention;

[0038] Figure 2 is Figure 1 an enlarged structural schematic diagram at A in

[0039] Figure 3 is Figure 1 an enlarged structural schematic diagram at B in

[0040] Figure 4 is Figure 1 an enlarged structural schematic diagram at C in

[0041] Description of the Reference Numerals:

[0042] 1 - housing; 101 - upper cover; 102 - main body; 103 - base; 2 - sample; 3 - axial pressure assembly; 31 - first press head; 32 - first mounting seat; 33 - second mounting seat; 34 - second press head; 35 - pressure loading structure; 351 - pressure loading rod; 352 - annular protrusion; 4 - protective sleeve; 5 - third press head; 51 - confining pressure flow channel; 52 - compensation flow channel; 53 - first flow channel; 54 - second flow channel; 6 - fixing sleeve; 7 - confining pressure connecting member; 8 - heating furnace; 9 - heat conducting sleeve; 10 - heat insulating sleeve; 11 - heat insulating ring; 12 - fluid inlet connecting member; 13 - fluid outlet connecting member; 14 - third sealing ring. Detailed Embodiments

[0043] To make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention will be given with reference to the drawings.

[0044] It should be noted that in the coordinate system XZ provided in this article, the positive direction of the X-axis represents the right side, the negative direction of the X-axis represents the left side, the positive direction of the Z-axis represents the upper side, and the negative direction of the Z-axis represents the lower side. At the same time, it should be noted that the terms "first", "second", etc. in the specification, claims and the above-mentioned drawings of the present invention are used to distinguish similar objects and do not have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here.

[0045] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "set", "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] In the description of this specification, the descriptions referring to terms such as "embodiment", "one embodiment" and "one implementation manner" mean that the specific features, structures, materials or characteristics described in connection with the embodiment or implementation manner are included in at least one embodiment or implementation manner of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or implementation manner. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or implementation manners.

[0047] To solve the above technical problems, in combination with Figure 1 As shown, the embodiment of the present invention provides a high-temperature and high-pressure experimental device, which includes a housing 1 and a triaxial pressure assembly. The triaxial pressure assembly includes an axial pressure component 3 and a protective sleeve 4. A main cavity is provided inside the housing 1, and at least part of the axial pressure component 3 is embedded in the main cavity;

[0048] The axial pressure component 3 includes a first pressure head 31, a first mounting seat 32, a second mounting seat 33, a second pressure head 34 and a pressure loading structure 35 arranged in sequence along the axis of the housing 1. A sample chamber is formed between the first mounting seat 32 and the second mounting seat 33, and a sample 2 is installed in the sample chamber;

[0049] The protective sleeve 4 is sleeved on part of the first pressure head 31 and the second pressure head 34, as well as the first mounting seat 32, the sample 2 and the second mounting seat 33.

[0050] It should be noted that at least a part of the axial compression assembly 3 is located in the main cavity of the housing 1, so the housing 1 provides an installation space for the axial compression assembly 3; the axis of the housing 1 is parallel to the Z-axis of the coordinate system of Figure 1 When the axial compression assembly 3 is installed in the main cavity, a sample chamber is formed between the first mounting seat 32 and the second mounting seat 33. The sample 2 is installed in the sample chamber. The sample 2 can be a standard-size sample or a small sample; during the axial compression test, the first pressing head 31 and / or the second pressing head 34 will generate a small displacement due to the compression of the sample 2. Since the protective sleeve 4 is sleeved on the lower part of the first pressing head 31 and the upper part of the second pressing head 34, the top and bottom ends of the protective sleeve 4 will not interfere with the axial compression displacement of the first pressing head 31 and the second pressing head 34, so as to ensure the smooth progress of the axial compression test.

[0051] Preferably, at least one sealing gasket is installed between the inner wall of the top end of the protective sleeve 4 and the outer wall of the upper end of the first pressing head 31, and between the inner wall of the bottom end of the protective sleeve 4 and the outer wall of the lower end of the second pressing head 34. During the axial compression test, the protective sleeve 4 and the sample 2 will undergo a certain amount of axial compression deformation. The deformation amount of the sample 2 usually does not exceed 20%. The first pressing head 31 and the second pressing head 34 will generate a small vertical displacement. Since there is a certain gap between the top end of the protective sleeve 4 and the lower part of the first pressing head 31, and between the bottom end of the protective sleeve 4 and the upper part of the second pressing head 34, the top and bottom ends of the protective sleeve will not interfere with the process of the distance between the first pressing head 31 and the second pressing head 34 becoming smaller; and the above two groups of sealing gaskets can also prevent the confining pressure fluid from entering the sample along the inner wall of the protective sleeve 4 from the above gaps between the top end of the protective sleeve 4 and the upper end of the first pressing head 31 and between the bottom end of the protective sleeve 4 and the lower end of the second pressing head 34 during the subsequent confining pressure test, so as to avoid interfering with the subsequent pore pressure test results of the sample. The protective sleeve 4 can be a copper sleeve or other metal sleeves with certain mechanical stiffness and sealing performance.

[0052] Compared with the prior art, when performing axial compression tests in the triaxial experiment on a sample 2, such as a small sample, in this embodiment, the top and bottom ends of the axial compression assembly 3, such as the first indenter 31 and the pressure loading structure 35, can be respectively abutted against the fixed frame and the telescopic rod of the press. The press applies an axial pressure to the axial compression assembly 3 and acts on the small sample to achieve the axial compression test on the small sample. During the axial compression test, since the protective sleeve 4 is sleeved on the lower part of the first indenter 31 and the upper part of the second indenter 34, as well as the first mounting seat 32, the sample 2, and the second mounting seat 33. In other words, the protective sleeve 4 always fixes the first indenter 31 and the second indenter 34, as well as the first mounting seat 32, the sample 2, and the second mounting seat 33 on the same vertical axis, which can play a positioning role for the sample 2, effectively preventing the sample 2 from being bent or offset during the axial compression test, etc., to ensure the normal operation of the axial compression test operation. It can not only be applicable to the triaxial experiment of small samples, but also to the triaxial experiment of standard-sized samples, thus expanding the applicable range of the high-temperature and high-pressure experimental device. Moreover, it can also effectively prevent the confining pressure fluid from directly entering the sample 2 during the subsequent confining pressure test by means of the sealing gaskets between the protective sleeve 4 and the first indenter 31 and the second indenter 34, thereby interfering with the subsequent pore pressure test on the sample 2.

[0053] Furthermore, since the protective sleeve 4 is only sleeved on a part of the first indenter 31 and a part of the second indenter 34. In other words, a certain interval is reserved between the top and bottom ends of the protective sleeve 4 and the top and bottom ends of the first indenter 31 and the second indenter 34 respectively. This interval can be used as the deformation distance of the sample when the press applies an axial pressure to the axial compression assembly 3. For example, during the axial compression test, the sample 2 is compressed and shortened, and the distance between the first indenter 31 and the second indenter 34 becomes smaller. During this process, since the intervals reserved at the top and bottom ends of the protective sleeve 4 will not interfere with the axial compression test operation of the press on the sample 2 through the axial compression assembly 3 until the axial compression test ends, there is a small interval or they are abutted between the top and bottom ends of the protective sleeve 4 and the top and bottom ends of the first indenter 31 and the second indenter 34 respectively, so that the protective sleeve 4 will not interfere with the axial compression test operation of the press on the small sample through the axial compression assembly 3, ensuring the smooth progress of the axial compression test.

[0054] In addition, the first indenter 31, the first mounting seat 32, the second mounting seat 33, the second indenter 34, and the pressure loading structure 35 can be in a split form, such as a detachable connection method, which not only facilitates the loading and unloading of the sample 2, but also can avoid the fracture of the relatively long second indenter 34 and the pressure loading structure 35 during the process of taking out the sample 2, correspondingly reducing the maintenance frequency and extending their service life.

[0055] In one embodiment of the present invention, in combination with Figure 1 and Figure 2As shown, the three-axis pressure assembly further includes a third indenter 5 and a fixing sleeve 6. The third indenter 5 is embedded in the main cavity, and the third indenter 5 is slidably sleeved on the pressure loading structure 35;

[0056] The pressure loading structure 35 includes a pressure loading rod 351 and an annular protrusion 352 arranged coaxially. The annular protrusion 352 is fixedly sleeved on the outer circumferential wall of the pressure loading rod 351. The interior of the third indenter 5 is provided with a first cavity and a second cavity that communicate successively along the axial direction of the pressure loading rod 351. The fixing sleeve 6 is embedded in the first cavity, and the fixing sleeve 6 is sleeved on the top ends of the second indenter 34 and the pressure loading rod 351. The annular protrusion 352 is slidably arranged in the second cavity.

[0057] It should be noted that in combination with Figures 2 to 4 As shown, the machine shell 1 may include an upper cover 101, a main body 102, and a base 103. Among them, a main cavity is arranged inside the main body 102. The axial pressure assembly 3 is arranged in the main cavity. The upper cover 101 is arranged at the top end of the main body 102, and the upper cover 101 and the top end of the main body 102 can be connected by a threaded connection. The upper cover 101 is connected to the first indenter 31 of the axial pressure assembly 3 to prevent the first indenter 31 from detaching from the upper cover 101 during the axial pressure test. The base 103 is arranged at the bottom end of the main body 102, and the base 103 and the bottom end of the main body 102 can be connected by a bolt fastener. The base 103 is connected to the third indenter 5 of the axial pressure assembly 3 to support the third indenter 5 from the bottom.

[0058] When the press applies an axial pressure to the sample 2 through the axial pressure assembly 3, the sample 2 will undergo a certain amount of deformation and shrinkage. The pressure loading structure 35 can perform an axial displacement relative to the third indenter 5. Among them, the annular protrusion 352 can axially move in the second cavity. At this time, the fixing sleeve 6 can play an upper limit position role for the annular protrusion 352, and the inner bottom wall of the second cavity can play a lower limit position role for the annular protrusion 352. The first cavity provides an installation space for the fixing sleeve 6. Since the fixing sleeve 6 is sleeved on the top ends of the second indenter 34 and the pressure loading rod 351, the fixing sleeve 6 can, while playing an upper limit position role for the annular protrusion 352, also apply a circumferential supporting force to the second indenter 34 and the pressure loading rod 351 to prevent the pressure loading structure 35 from bending and deforming during the axial pressure test due to its excessive length, thereby ensuring the accuracy of the axial pressure test on the sample 2.

[0059] Among them, the pressure loading rod 351 and the annular protrusion 352 can be an integrally formed structure, so as to ensure that the pressure loading structure 35 has a certain mechanical stiffness and strength.

[0060] In an embodiment of the present invention, in combination with Figure 1 and Figure 3As shown, a circumferential pressure chamber is formed between the inner wall of the protective sleeve 4 and the casing 1;

[0061] The three-axis pressure assembly further includes a heating furnace 8 and two heat conduction sleeves 9. The casing 1 has a convex structure, and the convex structure surrounds the sample chamber. The heating furnace 8 is sleeved on the narrow part of the convex structure;

[0062] The two heat conduction sleeves 9 are arranged at intervals along the axial direction of the casing 1, and the heat conduction sleeves 9 are sleeved outside the protective sleeve 4. The two heat conduction sleeves 9 respectively wrap the joints between the sample 2 and the first mounting seat 32 and between the sample 2 and the second mounting seat 33;

[0063] A first channel for the circumferential pressure fluid to flow through is formed between the heat conduction sleeve 9 and the inner wall of the casing 1, and / or a second channel for the circumferential pressure fluid to flow through is formed between the heat conduction sleeve 9 and the protective sleeve 4.

[0064] It should be noted that a circumferential pressure chamber is formed between the outer wall of the protective sleeve 4 and the inner wall of the casing 1. The convex structure can be an annular convex structure. Among them, the convex structure includes a narrow part and a wide part that are axially distributed along the casing 1 and integrally formed. The narrow part is above the wide part, and the diameter of the narrow part is smaller than that of the wide part. The heating furnace 8 includes a plurality of heating covers arranged in a ring. When the plurality of heating covers arranged in a ring surround and wrap a part of the structure of the main body 102 in the casing 1, that is, the narrow part area of the convex structure, the heat generated can be evenly dissipated from the circumferential direction through the plurality of heating covers arranged in a ring, and can be transferred to the circumferential pressure chamber wrapping the sample chamber faster through the narrow part of the convex structure to heat the circumferential pressure fluid in the circumferential pressure chamber. Furthermore, through the plurality of heating covers arranged in a ring, the circumferential pressure fluid in the circumferential pressure chamber is heated more evenly from the circumferential direction, effectively improving the heating efficiency and heating effect on the sample 2.

[0065] The first mounting seat 32 and the second mounting seat 33 can be cylindrical structures made of corundum ceramics, so as to ensure that the first mounting seat 32 and the second mounting seat 33 have certain mechanical stiffness, strength, and high-temperature resistance characteristics, and further meet the high-temperature and high-pressure experiment requirements for the sample 2. Among them, the first mounting seat 32 and the second mounting seat 33 can be set as slender cylindrical structures according to the characteristics of the experimental device.

[0066] The heat-conducting sleeve 9 can be a sleeve structure made of graphite material. Since the heat-conducting sleeve 9 is sleeved on the protective sleeve 4, and the bottom end of the upper heat-conducting sleeve 9 extends and wraps around the connection between the first mounting seat 32 and the sample 2, and the top end of the lower heat-conducting sleeve 9 extends and wraps around the connection between the second mounting seat 33 and the sample 2, the two heat-conducting sleeves 9 can respectively perform circumferential fixing and protection on the first mounting seat 32 and the sample 2, and between the sample 2 and the second mounting seat 33, further strengthening the positioning effect on the sample 2 to prevent problems such as bending, deformation, and breakage of the slender first mounting seat 32 and the second mounting seat 33 during the axial compression test. And, since a first channel for the confining pressure fluid to flow through is formed between the heat-conducting sleeve 9 and the inner wall of the machine housing 1, and / or a second channel for the confining pressure fluid to flow through is formed between the heat-conducting sleeve 9 and the protective sleeve 4, the heated confining pressure fluid can not only pass through the first channel and / or the second channel and flow to the sample chamber, and be transferred to the sample 2 through the protective sleeve 4 to provide a high-temperature environment for the sample 2, but also when the second channel is formed between the heat-conducting sleeve 9 and the protective sleeve 4 and the confining pressure fluid passes through the second channel, the heat-conducting sleeve 9 can transfer the heat of the confining pressure fluid to the sample 2 more evenly, making the heat distribution around the sample 2 more uniform, closer to the geological environment where the sample 2 was previously located, thereby improving the accuracy of various mechanical data in the triaxial test of the sample 2.

[0067] In addition, because the heat-conducting sleeve 9 has good heat-conducting characteristics, it can also play a certain role in heating the confining pressure fluid to avoid too rapid a decrease in the temperature around the sample 2, so that the sample 2 is in a high-temperature environment required for the experiment for a longer time, further improving the accuracy of various mechanical data in the triaxial test of the sample 2.

[0068] Furthermore, since the two heat-conducting sleeves 9 are arranged at intervals along the axial direction of the machine housing 1, in other words, the two heat-conducting sleeves 9 are a split structure in the upper and lower sections, the convenience of loading and unloading the sample 2 can be improved. Specifically, if the two heat-conducting sleeves 9 are of an integral structure, then if the sample 2 in the protective sleeve 4 is slightly deformed, it will be difficult to take out the heat-conducting sleeve 9 from the outside of the protective sleeve 4 after the experiment.

[0069] Specifically, the vertical section of the main body 102 of the casing 1 is a convex structure. Thus, on the basis that the narrow part of the convex structure ensures a certain high-pressure resistance safety of the triaxial pressure assembly, the heating furnace 8 located at the narrow part of the convex structure can transfer the generated heat to the confining pressure fluid in the confining pressure cavity faster and more concentratedly. Since the two heat conduction sleeves 9 are arranged at intervals along the axial direction of the main body 102 in the casing 1 and the heat conduction sleeves 9 are sleeved outside the protective sleeve 4, when the heating furnace 8 heats the confining pressure fluid, it also heats the two heat conduction sleeves 9. At this time, the heat conduction sleeves 9 and the confining pressure fluid can transfer the heat of the heating furnace 8 to the sample chamber faster and more evenly through the protective sleeve 4, thereby improving the experimental efficiency of the sample 2 in a high-temperature environment, and also enhancing the heating efficiency of the heating furnace 8 for the sample chamber, so as to correspondingly increase the ambient temperature around the sample 2, and further enabling the triaxial pressure assembly to meet the experimental requirements of current high temperature and high pressure.

[0070] In addition, as shown in Figure 2 , the triaxial pressure assembly further includes a confining pressure connecting member 7. A confining pressure inlet, a confining pressure flow channel 51 and a compensation flow channel 52 are provided on the third pressure head 5. One end of the confining pressure connecting member 7 is used to communicate with a confining pressure device that provides confining pressure fluid, and the other end communicates with the confining pressure inlet. A confining pressure cavity is formed between the protective sleeve 4 and the inner wall of the casing 1. The two ends of the confining pressure flow channel 51 communicate with the confining pressure inlet and the confining pressure cavity respectively; a compensation chamber is formed between the annular protrusion 352 and the inner bottom wall of the second cavity. The two ends of the compensation flow channel 52 communicate with the confining pressure inlet and the compensation chamber respectively.

[0071] It should be noted that the confining pressure connecting member 7 can be a sealed pipe joint through which the confining pressure fluid output by the confining pressure device enters the confining pressure flow channel 51. The confining pressure device is used to input confining pressure fluid into the confining pressure cavity through the confining pressure inlet.

[0072] Generally, when the confining pressure device conducts a confining pressure test on the sample 2, the press applies an axial pressure to the sample 2 through the axial pressure assembly 3. When the pressure loading structure 35 in the axial pressure assembly 3 slides and expands relative to the third pressure head 5 of the casing 1, it is very likely to cause a confining pressure fluctuation of the sample 2, thereby affecting the accuracy of the confining pressure test on the sample 2. Therefore, during the confining pressure test, the compensation chamber is communicated with the compensation flow channel 52, so that after the confining pressure fluid output by the confining pressure device enters the confining pressure inlet, it is divided. One part enters the compensation chamber through the compensation flow channel 52, and the other part enters the confining pressure cavity through the confining pressure flow channel 51 until it flows to the outer area of the protective sleeve 4 corresponding to the sample 2. At this time, the confining pressure fluid in the confining pressure cavity applies a confining pressure to the sample 2 through the protective sleeve 4, thereby realizing the confining pressure test on the sample 2.

[0073] Specifically, by connecting the compensation chamber with the confining pressure chamber, when the pressure loading structure 35 moves upward by extrusion, the confining pressure in the confining pressure chamber increases, while the pressure in the compensation chamber decreases accordingly. At this time, the confining pressure fluid in the confining pressure chamber can flow into the compensation chamber through the confining pressure channel and the compensation channel, so as to ensure that the pressure in the confining pressure chamber remains unchanged and avoid confining pressure fluctuations. On the contrary, when the pressure loading structure 35 moves downward and retreats, the confining pressure in the confining pressure chamber decreases, and because the annular protrusion in the pressure loading structure 35 moves downward, the pressure in the compensation chamber will increase accordingly. At this time, the confining pressure fluid in the compensation chamber can enter the confining pressure chamber through the compensation channel and the confining pressure channel, so as to also ensure that the pressure in the confining pressure chamber remains unchanged and avoid confining pressure fluctuations.

[0074] In an embodiment of the present invention, the triaxial pressure assembly further includes two heat insulation sleeves 10. The two heat insulation sleeves 10 are arranged at intervals along the axial direction of the machine shell 1. The heat insulation sleeves 10 are sleeved outside the protective sleeve 4, and the two heat conduction sleeves 9 are located between the two heat insulation sleeves 10;

[0075] A third channel for the confining pressure fluid to flow through is formed between the heat insulation sleeve 10 and the inner wall of the machine shell 1, and / or a fourth channel for the confining pressure fluid to flow through is formed between the heat insulation sleeve 10 and the protective sleeve 4.

[0076] It should be noted that the heat insulation sleeve 10 can be a sleeve structure made of metal such as titanium alloy. Since the heat insulation sleeve 10 is sleeved outside the protective sleeve 4, and the upper heat insulation sleeve 10 is above the heat conduction sleeve 9, and the lower heat insulation sleeve 10 is below the heat conduction sleeve 9. Among them, the top end of the upper heat insulation sleeve 10 extends and wraps a part of the structure of the first pressure head 31, and the bottom end of the lower heat insulation sleeve 10 extends and wraps a part of the structure of the second pressure head 34. Thus, the cooperation of the two heat conduction sleeves 9 and the two heat insulation sleeves 10 can fix the first pressure head 31, the first mounting seat 32, the second mounting seat 33 and the second pressure head 34 in the axial compression assembly 3 and the sample 2 on the same axis and perform circumferential fixing and protection to further prevent the slender first mounting seat 32 and the second mounting seat 33 from bending, deforming, breaking, etc. during the axial compression test; moreover, the confining pressure fluid can also flow from the third channel and / or the fourth channel to the sample chamber. And because the heat conduction directions of the heat conduction sleeve 9 and the heat insulation sleeve 10 are different, it can effectively reduce the heat convection of the confining pressure fluid when flowing through the second channel and the fourth channel, so that the heat of the confining pressure fluid is more concentrated on the sample 2 in the protective sleeve 4 to ensure the accuracy of the temperature measurement of the sample 2 by the thermocouple and avoid large fluctuations in the temperature of the sample 2.

[0077] In addition, the heat insulation sleeve 10 above the sample 2 can reduce the upward transfer of heat generated by the heating furnace 8, thereby correspondingly reducing the influence of such heat on the sealing performance between the first indenter 31 and the inner wall of the housing 1. The heat insulation sleeve 10 below the sample 2 can reduce the downward transfer of heat generated by the heating furnace 8, thereby correspondingly reducing the influence of such heat on the sealing performance between the third indenter 5 and the inner wall of the housing 1.

[0078] Furthermore, since the two heat insulation sleeves 10 are arranged at intervals along the axial direction of the housing 1, in other words, the two heat insulation sleeves 10 are of a split structure in upper and lower sections, the convenience of loading and unloading the sample 2 can be improved. Specifically, if the two heat insulation sleeves 10 are of an integral structure, then if the sample 2 in the protective sleeve 4 is slightly deformed, it will be difficult to take out the heat insulation sleeve 10 from the outside of the protective sleeve 4 after the experiment.

[0079] In an embodiment of the present invention, the triaxial pressure assembly further includes a thermocouple. Installation grooves are provided on the inner walls of the heat insulation sleeve 10 and the heat conduction sleeve 9. One end of the thermocouple is outside the first indenter 31, and the other end of the thermocouple sequentially passes through the first indenter 31 and the installation grooves of the heat insulation sleeve 10 and the heat conduction sleeve 9 and extends to the sample chamber.

[0080] It should be noted that the number of thermocouples can be at least one. During the process of loading the sample 2, one end of a thermocouple is outside the first indenter 31 and is connected to a temperature control device. The other end of the thermocouple sequentially passes through the first indenter 31 and the installation grooves of the heat insulation sleeve 10 and the heat conduction sleeve 9 and extends to the sample chamber to perform real-time detection of the temperature of the sample 2.

[0081] The temperature of the confining pressure chamber can also be measured. For example, one end of another thermocouple is outside the first indenter 31 and is connected to a temperature control device. The other end of the other thermocouple is at different height positions of the confining pressure chamber to measure the different temperatures at different heights of the confining pressure chamber for detecting the temperature difference in the confining pressure chamber.

[0082] The protective sleeve 4 can be a copper tube. Installation grooves for the thermocouple to pass through are provided inside the heat conduction sleeve 9 and the heat insulation sleeve 10. The installation grooves are used to fix the position of the thermocouple to prevent the position of the thermocouple from changing during the axial compression process, thereby improving the accuracy of temperature acquisition of the sample 2.

[0083] Since a second channel for the confining pressure fluid to flow through is formed between the heat-conducting sleeve 9 and the protective sleeve 4, and a fourth channel for the confining pressure fluid to flow through is formed between the heat-insulating sleeve 10 and the protective sleeve 4, when the sample is subjected to axial compression testing, the sample will undergo axial compression deformation. Therefore, the second channel and the fourth channel respectively provide deformation spaces for the heat-conducting sleeve 9 and the heat-insulating sleeve 10, so as to prevent the heat-conducting sleeve 9 and the heat-insulating sleeve 10 from undergoing axial deformation when the sample undergoes axial deformation, and crushing the heat-conducting sleeve 9 and the heat-insulating sleeve 10, thereby realizing the protection of the heat-conducting sleeve 9 and the heat-insulating sleeve 10.

[0084] In addition, the temperature of the sample chamber can reflect the temperature of the sample 2, and the temperature of the sample 2 collected by the thermocouple is received through the temperature control device to control the operation and stop of the heating furnace 8, thereby realizing the control of the temperature of the sample chamber.

[0085] In an embodiment of the present invention, in combination with Figure 1 and Figure 4 as shown, the triaxial pressure assembly further includes a heat-insulating ring 11, the heat-insulating ring 11 is sleeved outside the protective sleeve 4, and the heat-insulating ring 11 is located between the heat-insulating sleeve 10 and the first pressing head 31.

[0086] It should be noted that the heat-insulating ring 11 is used to further reduce the heat transfer to the third sealing ring 14 installed between the first pressing head 31 and the inner wall of the main body 102 of the machine shell 1 on the basis of the heat-insulating sleeve 10 reducing the heat of the heat-conducting sleeve 9, so as to avoid the heat reducing the sealing performance between the first pressing head 31 and the inner wall of the main body 102 of the machine shell 1, and effectively avoid the confining pressure fluid from discharging outward from the third sealing ring 14; moreover, the heat-insulating ring 11 can also protect the sealing performance between the first pressing head 31 and the protective sleeve 4, and avoid the confining pressure fluid from entering the sample and communicating with the pore fluid. Among them, the heat-insulating ring 11 can adopt a circular ring structure supported by polytetrafluoroethylene material.

[0087] In an embodiment of the present invention, in combination with Figure 2 and Figure 4 as shown, the triaxial pressure assembly further includes a fluid inlet connector 12 and a fluid outlet connector 13. Fluid inlet channels and fluid outlet channels are respectively provided inside the axial compression assembly 3. The fluid inlet connector 12 and the fluid outlet connector 13 are respectively communicated with the fluid inlet connector 12 and the fluid outlet connector 13. The fluid inlet connector 12 is used to communicate with a pore pressure device that provides pore fluid;

[0088] The fluid inlet channel and the fluid outlet channel respectively extend to opposite end faces of the sample 2.

[0089] It should be noted that a fluid inlet channel is provided inside a part of the structure of the axial compression assembly 3 below the sample 2. The fluid inlet connector 12 can be arranged at the bottom end of the fluid inlet channel opened on the pressure loading structure 35 in the axial compression assembly 3. A fluid outlet channel is provided inside a part of the structure of the axial compression assembly 3 above the sample 2, and the fluid outlet connector 13 can be arranged at the top end of the fluid outlet channel opened on the first platen 31 in the axial compression assembly 3; the fluid inlet connector 12 is used to connect the pore pressure device that provides pore fluid.

[0090] Of course, in other embodiments, the fluid inlet channel can also be arranged in the axial compression assembly 3 above the sample 2, and the fluid outlet channel can also be arranged in the axial compression assembly 3 below the sample 2.

[0091] When performing a pore pressure test on the sample 2, the pore fluid can be output through the pore pressure device. Subsequently, the pore fluid enters the sample 2 from the lower end along the fluid inlet channel, permeates inside the sample 2, and then is discharged from the fluid outlet channel, thereby realizing the pore pressure test on the sample 2.

[0092] In an embodiment of the present invention, as shown in Figure 2 the triaxial pressure assembly further includes a first sealing ring, a second sealing ring and a detection device. The first sealing ring is embedded between the fixed sleeve 6 and the pressure loading rod 351; the second sealing ring is embedded between the fixed sleeve 6 and the third platen 5.

[0093] A third cavity is formed between the annular protrusion 352 and the fixed sleeve 6. The third platen 5 is also provided with a first flow channel 53 and a second flow channel 54 that communicate with each other. The second flow channel 54 communicates with the third cavity through the first flow channel 53. The detection device communicates with the second flow channel 54 and is used to detect whether leakage occurs at the first sealing ring and the second sealing ring for the confining pressure fluid conveyed to the confining pressure cavity by the confining pressure device, and the exhaust pressure of the air in the third cavity from the second flow channel 54.

[0094] It should be noted that the first sealing ring is embedded between the inner wall of the fixed sleeve 6 and the outer wall of the pressure loading rod 351. Therefore, the first sealing ring is used to seal between the fixed sleeve 6 and the pressure loading rod 351; the second sealing ring is embedded between the outer wall of the fixed sleeve 6 and the circumferential inner wall of the third platen 5 in the first cavity. Therefore, the second sealing ring is used to seal between the fixed sleeve 6 and the third platen 5.

[0095] A third cavity is formed between the top end of the annular protrusion 352 and the bottom end of the fixed sleeve 6. It can be understood that the compensation chamber, the partial cavity where the annular protrusion 352 is located, and the third cavity together constitute the second cavity of the third pressure head 5. When the press applies an axial pressure to the sample 2 through the axial pressure assembly 3, the sample 2 is compressed, and the annular protrusion 352 moves upward in the second cavity. At this time, the volume of the compensation chamber becomes larger, while the volume of the third cavity becomes smaller. Therefore, the original air in the third cavity can be discharged along the second flow path 54 through the first flow path 53 to ensure the axial pressure test of the sample 2. And at this time, the detection device can detect the exhaust pressure in the third cavity discharged from the second flow path 54, and this exhaust pressure can also be used as an axial pressure data parameter in the subsequent mechanical data.

[0096] Among them, the detection device can be a pressure sensor, and the pressure sensor can be arranged on the pipeline communicated with the second flow path 54. For example, when the confining pressure device inputs confining pressure fluid into the confining pressure cavity and acts on the sample 2 to conduct the confining pressure test, if the pressure sensor shows a reading, it can be determined that the confining pressure fluid flows through the gap between the fixed sleeve 6 and the pressure loading rod 351, or between the fixed sleeve 6 and the third pressure head 5, and is discharged through the first flow path 53 and the second flow path 54, which may indicate that the first sealing ring or the second sealing ring may be leaking. Therefore, the detection device can be used to detect whether the confining pressure fluid transported by the confining pressure device to the confining pressure cavity leaks at the first sealing ring and the second sealing ring.

[0097] Another embodiment of the present invention provides an experimental system, including the high-temperature and high-pressure experimental device as described above, and further including a press, the press includes a frame and a telescopic rod, and the opposite ends of the axial pressure assembly 3 in the high-temperature and high-pressure experimental device are respectively connected to the frame and the telescopic rod correspondingly.

[0098] It should be noted that the press can be a uniaxial press. When the high-temperature and high-pressure experimental device is installed at the press, the two ends of the axial pressure assembly 3, such as the first pressure head 31 and the pressure loading structure 35, are respectively connected to the frame and the telescopic rod of the press. At this time, the telescopic rod of the press can apply an axial pressure to the sample 2 from the bottom upward.

[0099] The experimental system further includes a confining pressure device, a pore pressure device, and a cooling device. The confining pressure device is communicated with the confining pressure connecting member 7 to transport confining pressure fluid to the confining pressure cavity through the confining pressure connecting member 7, so as to apply confining pressure to the corresponding position of the sample 2 through the protective sleeve 4 to realize the confining pressure test of the sample 2; the pore pressure device can input pore fluid into the fluid inlet flow path through the fluid inlet connecting member 12 to conduct the pore pressure test on the sample 2.

[0100] The three-axis pressure assembly further includes a third sealing ring. An annular groove structure is provided on the outer wall of the first pressing head 31 near the third sealing ring 14. The central axis of the annular groove structure coincides with the central axis of the housing 1. A cooling chamber for cooling the third sealing ring is formed between the annular groove structure and the housing 1. Two cooling channels are further provided on the first pressing head 31. One ends of the two cooling channels are respectively communicated with the cooling chamber, and the other ends of the cooling channels are respectively communicated with a cooling device through the cooling pipe connector.

[0101] It should be noted that when the container body 102 is performing a three-axis experiment, the cooling device can output a cooling medium, which enters the cooling chamber through one of the cooling channels and is discharged from the other cooling channel, so as to cool the first pressing head 31 through the circulating cooling medium, thereby effectively reducing the temperature of the third sealing ring 14 and preventing the problem of sealing failure of the third sealing ring 14 due to the high temperature of the sample 2. Among them, the cooling device can adopt a chiller in the prior art, and as long as it can provide cold water or other cooling media to cool the first pressing head 31, the water cooling device is applicable to this technical solution and will not be specifically limited here.

[0102] The experimental system has all the technical effects of the high-temperature and high-pressure experimental device, which will not be elaborated here.

[0103] Another embodiment of the present invention provides an experimental method, based on the experimental system described above, including the following steps:

[0104] S1. Process the selected blank to form a sample 2 that meets the experimental requirements; wherein, the sample 2 is a cylindrical sample.

[0105] It should be noted that the blank can be a standard-size sample or a small sample, such as a blank with an irregular shape taken in the early stage, a blank with a small initial volume (such as drilling cuttings, planetary samples), etc. Such small samples cannot directly perform a three-axis experiment, and at this time, the selected blank needs to be processed to form a sample 2 that meets the experimental requirements.

[0106] S2. Assemble the sample 2 and the axial pressure assembly 3 into the housing 1 of the high-temperature and high-pressure experimental device.

[0107] It should be noted that the sample 2, the axial pressure assembly 3, the protective sleeve 4, the third pressing head 5, and two heat-conducting sleeves 9 and two heat-insulating sleeves 10 are installed in the main body 102 of the housing 1 in a certain assembly order to form a three-axis pressure assembly. At this time, the third pressing head 5 and the pressure loading structure 35 are located below the sample 2 (as shown in Figure 2 shown), and the first pressing head 31 and the cooling chamber are located above the sample 2.

[0108] S3. Apply axial pressure to the axial compression assembly 3 through the press to conduct an axial compression experiment, and collect first axial compression data in real time.

[0109] It should be noted that when the high-temperature and high-pressure experimental device is placed on the press, the first indenter 31 and the pressure loading structure 35 are respectively in contact with the fixed frame and the telescopic rod of the press. Axial upward pressure can be applied to the axial compression assembly 3 in the triaxial pressure assembly through the press to conduct an axial compression experiment on the sample 2, and the first axial compression data of the sample 2 is collected in real time. Among them, the first axial compression data at least includes the rising height of the axial compression rod structure and the axial compression pressure value of the press on the sample 2.

[0110] S4. Control the confining pressure device of the experimental system to fill the confining pressure fluid into the confining pressure chamber where the sample 2 is located and the compensation chamber of the triaxial pressure assembly, so that the triaxial pressure assembly is in a hydrostatic state.

[0111] It should be noted that the confining pressure device is used to output the confining pressure fluid. Among them, the confining pressure fluid output by the confining pressure device is shunted after passing through the confining pressure inlet of the third indenter 5. One part flows into the confining pressure chamber along the confining pressure channel 51 and flows to the sample chamber to apply confining pressure to the protective sleeve 4 as the confining pressure of the sample 2, while the other part flows into the compensation chamber along the compensation channel 52 to compensate for the confining pressure fluctuation in the confining pressure chamber above the pressure loading structure 35 when the pressure loading structure 35 slides up and down relative to the third indenter 5 of the machine housing 1 during the axial loading of the press. Thus, the axial compression received by the sample 2 is the same as the confining pressure received in the circumferential direction, so that the triaxial pressure assembly is in a hydrostatic state.

[0112] S5. Control the pore pressure device to input pore fluid to the sample 2, increase the flow rate of the confining pressure fluid multiple times, apply axial pressure to the axial compression assembly 3 multiple times, and collect and record the mechanical data of the sample 2.

[0113] It should be noted that the experimental system also includes a temperature control device. Among them, the thermocouple is electrically connected to the signal terminal of the temperature control device, and the temperature control device is electrically connected to the heating furnace 8 to control the operation or stop of the heating furnace 8 according to the working temperature of the sample 2.

[0114] The pore pressure device outputs pore fluid to apply a certain pore pressure (lower than the confining pressure), and then the pressure of the pore fluid is collected and recorded by an external detection device such as a pressure sensor.

[0115] The flow rate of the confining pressure fluid can be increased multiple times to the confining pressure chamber through the confining pressure device, and the current confining pressure data of the sample 2 is collected and recorded; different axial pressures can be applied to the axial compression assembly 3 multiple times through the press, and the current axial compression data of the sample 2 is collected and recorded.

[0116] Therefore, the mechanical data includes the current pore pressure data, the current confining pressure data, and the current axial pressure data corresponding to the sample 2 when the flow rate of the pore fluid, the flow rate of the confining pressure fluid, the axial pressure, and the axial displacement are increased for the sample 2 each time.

[0117] S6. Save the mechanical data, unload the axial pressure, the confining pressure fluid, and the pore fluid, disassemble the triaxial pressure assembly, and take out the sample 2.

[0118] It should be noted that during the process of performing the triaxial experiment on the axial pressure, the confining pressure, and the pore pressure of the sample 2 under high temperature and high pressure conditions, after the mechanical data of the sample 2 is collected in real time, when the experiment ends, the mechanical data is preferably saved first, and then the axial pressure, the confining pressure fluid, and the pore fluid are unloaded, and then the triaxial pressure assembly is disassembled, and the sample 2 is taken out.

[0119] Since the experimental method is based on the experimental system as described above, the experimental method at least has all the technical effects of the experimental system, which will not be elaborated here.

[0120] In an embodiment of the present invention, S1. The processing of the selected blank to form the sample 2 that meets the experimental requirements includes:

[0121] S11. Select a blank that meets the experimental requirements;

[0122] S12. Fix and repair the blank with a glue-like substance;

[0123] S13. Grind the repaired blank to form the sample 2 that meets the experimental requirements.

[0124] It should be noted that in step S11, the method of manual selection can be used to select a blank that meets the experimental requirements. The blank can be a standard size sample, or a precious sample, a sample with an irregular shape, or a sample with a small initial volume (such as drilling cuttings, planetary samples).

[0125] In step S12, the blank can be first placed in a container on the workbench, a glue-like substance such as epoxy resin is poured on the surface of the blank, and then the blank with the glue-like substance is fixed by a fixture, and then the blank with the glue-like substance is repaired by a tool to form a blank close to a cylindrical shape.

[0126] In step S13, the repaired blank can be ground by a tool or a lathe to form the sample 2 that meets the experimental requirements, such as a cylindrical sample 2.

[0127] Although the present invention is disclosed as above, the scope of protection of the present invention is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will all fall within the scope of protection of the present invention.

Claims

1. A high-temperature and high-pressure experimental device, characterized in that, It includes a housing (1) and a triaxial pressure assembly. The triaxial pressure assembly includes an axial pressure component (3), a protective sleeve (4), a heating furnace (8), two heat-conducting sleeves (9) and two heat-insulating sleeves (10). A main cavity is provided inside the housing (1), and at least part of the axial pressure component (3) is embedded in the main cavity. The axial pressure component (3) includes a first punch (31), a first mounting seat (32), a second mounting seat (33), a second punch (34) and a pressure loading structure (35) arranged in sequence along the axial direction of the housing (1). A sample chamber is formed between the first mounting seat (32) and the second mounting seat (33), and a sample (2) is installed in the sample chamber. The protective sleeve (4) is sleeved on part of the first punch (31) and the second punch (34), as well as the first mounting seat (32), the sample (2) and the second mounting seat (33). A confining pressure chamber is formed between the protective sleeve (4) and the inner wall of the housing (1). The housing (1) is of a convex structure, and the convex structure surrounds the sample chamber. The heating furnace (8) is sleeved on the narrow part of the convex structure and is used to heat the confining pressure fluid in the confining pressure chamber. The two heat-conducting sleeves (9) are arranged at intervals along the axial direction of the housing (1), and the heat-conducting sleeves (9) are sleeved outside the protective sleeve (4). The two heat-conducting sleeves (9) respectively wrap the joints between the sample (2) and the first mounting seat (32) and between the sample (2) and the second mounting seat (33). The two heat-insulating sleeves (10) are arranged at intervals along the axial direction of the housing (1). The heat-insulating sleeves (10) are sleeved outside the protective sleeve (4), and the two heat-conducting sleeves (9) are located between the two heat-insulating sleeves (10).

2. The high-temperature and high-pressure experimental device according to claim 1, wherein The triaxial pressure assembly further includes a third punch (5) and a fixing sleeve (6). The third punch (5) is embedded in the main cavity, and the third punch (5) is slidably sleeved on the pressure loading structure (35). The pressure loading structure (35) includes a pressure loading rod (351) and an annular protrusion (352) arranged coaxially. The annular protrusion (352) is fixedly sleeved on the outer circumferential wall of the pressure loading rod (351). A first cavity and a second cavity are sequentially communicated along the axial direction of the pressure loading rod (351) inside the third punch (5). The fixing sleeve (6) is embedded in the first cavity, and the fixing sleeve (6) is sleeved on the top ends of the second punch (34) and the pressure loading rod (351). The annular protrusion (352) is slidably arranged in the second cavity.

3. The high-temperature and high-pressure experimental device according to claim 2, characterized in that, A first channel for the confining pressure fluid to flow through is formed between the heat-conducting sleeve (9) and the inner wall of the housing (1), and / or a second channel for the confining pressure fluid to flow through is formed between the heat-conducting sleeve (9) and the protective sleeve (4).

4. The high-temperature and high-pressure experimental device according to claim 3, wherein A third channel for the confining fluid to flow through is formed between the heat-insulating sleeve (10) and the inner wall of the housing (1), and / or a fourth channel for the confining fluid to flow through is formed between the heat-insulating sleeve (10) and the protective sleeve (4).

5. The high-temperature and high-pressure experimental device according to claim 4, wherein The triaxial pressure assembly further includes a thermocouple. Installation grooves are provided on the inner walls of the heat-insulating sleeve (10) and the heat-conducting sleeve (9). One end of the thermocouple is outside the first indenter (31), and the other end of the thermocouple sequentially passes through the first indenter (31) and the installation grooves of the heat-insulating sleeve (10) and the heat-conducting sleeve (9), and extends to the sample chamber.

6. The high-temperature and high-pressure experimental device according to claim 4, characterized in that The triaxial pressure assembly further includes a heat-insulating ring (11). The heat-insulating ring (11) is sleeved outside the protective sleeve (4), and the heat-insulating ring (11) is located between the heat-insulating sleeve (10) and the first indenter (31).

7. The high-temperature and high-pressure experimental device according to claim 3, wherein The triaxial pressure assembly further includes a first sealing ring, a second sealing ring and a detection device. The first sealing ring is embedded between the fixed sleeve (6) and the pressure loading rod (351), and the second sealing ring is embedded between the fixed sleeve (6) and the third indenter (5). A third cavity is formed between the annular protrusion (352) and the fixed sleeve (6). The third indenter (5) is further provided with a first flow channel (53) and a second flow channel (54) that communicate with each other. The second flow channel (54) communicates with the third cavity through the first flow channel (53). The detection device communicates with the second flow channel (54) and is used to detect whether leakage occurs at the first sealing ring and the second sealing ring of the confining fluid in the confining cavity, and the exhaust pressure of the air in the third cavity from the second flow channel (54).

8. An experimental system, characterized in that, It includes the high-temperature and high-pressure experimental device according to any one of claims 1 to 7, and further includes a press. The press includes a frame and a telescopic rod. The opposite ends of the axial pressure assembly (3) in the high-temperature and high-pressure experimental device are respectively connected to the frame and the telescopic rod.

9. An experimental method, based on the experimental system according to claim 8, characterized in that, It includes the following steps: Processing the selected blank to form a sample (2) that meets the experimental requirements; wherein, the sample (2) is a cylindrical sample. Assembling the sample (2) and the axial pressure assembly (3) into the housing (1) of the high-temperature and high-pressure experimental device. Applying an axial pressure to the axial pressure assembly (3) through the press to perform an axial pressure experiment, and collecting first axial pressure data in real time. Controlling the confining pressure device of the experimental system to fill the confining fluid into the confining cavity where the sample (2) is located and the compensation chamber of the triaxial pressure assembly, so that the triaxial pressure assembly is in a static pressure state. Controlling the pore pressure device to input pore fluid into the sample (2), increasing the flow rate of the confining fluid multiple times, applying an axial pressure to the axial pressure assembly (3) multiple times, and collecting and recording the mechanical data of the sample (2). Saving the mechanical data, unloading the axial pressure, the confining fluid and the pore fluid, disassembling the triaxial pressure assembly, and taking out the sample (2).

10. The experimental method according to claim 9, characterized in that, The processing the selected blank to form a sample (2) that meets the experimental requirements includes: Select blank materials that meet the experimental requirements; Fix and repair the blank materials with a gelling agent; Grind the repaired blank materials to form a sample (2) that meets the experimental requirements.

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