An auxiliary device for cold damage and fracture testing of hot dry rock

Abstract

This invention relates to an auxiliary device for a dry hot rock cold damage fracture test. The technical solution adopted by this invention is: an auxiliary device for a dry hot rock cold damage fracture test, characterized in that: it has a base plate for placement; on the base plate, via a transport mechanism, is an injection mechanism for filling the edge of the gap between two samples with epoxy resin and sealing the gap; on both sides of the base plate where the samples are placed, there are water pipe installation mechanisms for embedding water pipes into the epoxy resin between the two samples. Thus, the transport mechanism drives the injection mechanism to move uniformly around the samples on the base plate, facilitating the uniform injection of epoxy resin into the edge of the gap between the two samples; the water pipe installation mechanisms facilitate the installation of two water pipes into the epoxy resin on both sides of the samples, one water pipe serving as an inlet pipe and the other as an outlet pipe, realizing water circulation between the samples and the outside environment.

Description

Technical Field

[0001] This invention relates to an auxiliary device for cold damage and fracture testing of hot dry rock. It falls within the technical field of auxiliary equipment for hot dry rock cold damage and fracture testing. Background Technology

[0002] The secondary fracturing and permeability evolution induced by long-term cold water injection in hot dry rocks is one of the key issues to be addressed in the commercialization of hot dry rock geothermal energy. In artificial fracturing, the instantaneous injection of cold water causes shrinkage fracturing in high-temperature rocks, enhancing the hydraulic fracturing effect. However, quantitative research on the impact of this temperature effect on rock fracturing is limited, and the mechanism remains unclear. Therefore, studying the mechanism of cold damage fracturing in rocks is of significant engineering importance for controlling the scale and permeability evolution of hot dry rock reservoirs, maximizing benefits and minimizing risks.

[0003] In the experiment on cold damage fracture of hot dry rock, two rectangular specimens of specified dimensions are first prepared. Multiple high-strength blocks are used to support the two specimens, and the gap between them is controlled at 5 mm. The edges of the two specimens are sealed with epoxy resin. Then, water inlet and outlet holes are made. The specimens are then heated to a specified temperature, and cold water at the specified temperature is introduced into the gap between the two specimens through the water inlet holes. The water temperature and flow rate are measured through the water outlet holes. After the water temperature stabilizes, water injection is stopped, and the specimens are separated. By comparing the changes in the microstructure of the same cross-section before and after the experiment, the influence and mechanism of water-rock temperature difference and flow rate on cold damage fracture of the rock are analyzed and discussed.

[0004] In the process of sealing samples with epoxy resin, the epoxy resin is usually injected manually between two samples. On the one hand, it is difficult to ensure the accuracy of the injection position, and on the other hand, it is difficult to control the amount of epoxy resin applied. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: In order to solve the above-mentioned technical problem, the present invention provides an auxiliary device for dry hot rock cold damage cracking test to improve the accuracy of epoxy resin adhesive application amount.

[0006] The technical solution adopted in this invention is: an auxiliary device for a dry hot rock cold damage and fracture test, characterized in that it has:

[0007] A base plate on which a sample is placed, the sample having a specimen I placed on the base plate and a specimen II placed on the specimen I, with a gap between the specimen I and the specimen II due to the placement of several high-strength pads;

[0008] The injection mechanism, located on the base plate, is used to inject epoxy resin into the gap between specimen I and specimen II;

[0009] The transport mechanism, mounted on the base plate, has an injection mechanism fixedly installed on it. The transport mechanism drives the injection mechanism to move around the sample, uniformly injecting epoxy resin into the gaps around the sample and sealing them. Thus, after specimen I and specimen II are stacked sequentially on the base plate, multiple high-strength pads are placed between specimen I and specimen II to create a gap. The transport mechanism drives the injection mechanism to move uniformly around the sample on the base plate, facilitating the uniform injection of epoxy resin into the edges of the gap between the two specimens.

[0010] The injection mechanism includes a base, an injection cylinder, and a container. The base is fixedly mounted on the transport mechanism via a mounting bracket. The container is mounted on top of the injection cylinder and provides epoxy resin adhesive to it. The injection cylinder, mounted on the top surface of the base, injects the epoxy resin adhesive into the gap between two samples. Thus, the mounting bracket, fixedly connected to the transport mechanism, facilitates the movement of the base and the equipment mounted on it with the transport mechanism. The transport mechanism is arranged around the samples, ensuring that the epoxy resin adhesive sprayed from the injection cylinder is evenly applied into the gap between the two samples.

[0011] A groove is provided on the base along a direction perpendicular to the transport mechanism. A slider is installed in the groove and slides within it. The slider is driven by a drive cylinder fixedly mounted on the base. The syringe is fixedly connected to the slider via an adjusting seat. This facilitates adjustment of the injection position of the syringe.

[0012] The container has an opening at the top, and a sealing cap is threaded onto the opening. The sealing cap has several through holes that are sealed by a plunger. Thus, opening the sealing cap allows for easy filling of the container with epoxy resin. By removing the plunger from the through holes and adjusting the number of through holes sealed by the plunger, the air intake into the container can be changed, thereby adjusting the injection speed of the epoxy resin.

[0013] The transport mechanism has several support columns arranged on the base plate perpendicular to the top surface. These support columns are telescopically adjustable and rotatably mounted on the base plate along their axial direction. A sprocket, coaxially aligned with the top of each support column, is fixedly fitted onto its top. The sprockets are driven by the same chain. The sample is placed within the area enclosed by the chain. Thus, when one support column rotates around its axis, it drives the rotation of all support columns and the movement of the chain. As the injection mechanism moves with the chain, it sprays epoxy resin into the seal between the samples. Simultaneously, the telescopically adjustable support columns allow for adjustment of the chain's height, suitable for samples of different heights. When applied to samples of different heights, adjusting the height of the support columns adjusts the height of the chain and the injection mechanism on the base plate, ensuring that the epoxy resin within the injection mechanism is sprayed into the gap between sample I and sample II.

[0014] A driven gear is mounted on a support column, and a drive motor is installed on the base plate. A driving gear that meshes with the driven gear is mounted on the output shaft of the drive motor. In this way, the drive motor facilitates the uniform movement of the chain and injection mechanism around the sample, and also makes it easy to adjust the movement speed of the injection mechanism around the time.

[0015] A water pipe installation mechanism is installed on both sides of the base plate at positions where the specimen is placed, for embedding the water pipe into the epoxy resin between specimen I and specimen II. The water pipe installation mechanism has a mounting base, a mounting rod, and a mounting sleeve. The mounting rod is an adjustable telescopic mounting rod. The mounting base is fixedly installed on the base plate. One end of the mounting rod is hinged to the mounting base, and the mounting sleeve is fixedly installed on the other end of the mounting rod. A clamping pad for clamping the water pipe is installed on the inner wall of the mounting sleeve. Thus, when the water pipe needs to be installed, the mounting rod and mounting sleeve are rotated perpendicular to the top surface of the base plate via the hinge. By adjusting the mounting rod, the mounting sleeve and the water pipe installed in the mounting sleeve are moved to the corresponding position in the gap between specimen I and specimen II, and the water pipe is installed in the epoxy resin on both sides of the specimen. After the epoxy resin solidifies, the water pipe is also fixedly installed on the specimen.

[0016] The water pipe has a sealant attached to one end near the sample, and a removal device is installed inside the water pipe for removing the sealant after the water pipe is embedded in epoxy resin.

[0017] The removal device includes a push-pull block disposed inside the water pipe. The push-pull block is connected to a sealant patch, and the push-pull block is connected to a hand-held rod disposed on the water pipe at the end furthest from the sample via a push-pull rod. Thus, when installing the water pipe into the sample gap coated with epoxy resin, the sealant patch effectively prevents epoxy resin from entering the water pipe and causing blockage during subsequent testing. After the water pipe is fixedly installed in the sample gap, pulling the hand-held rod outward moves the push-pull rod and push-pull block out of the water pipe, thereby removing the sealant patch from the water pipe.

[0018] The water pipe has a limiting step on its inner wall near the sample to prevent the push-pull block from moving out of the water pipe. This effectively prevents the sealant from falling off from the side of the water pipe toward the gap when it is installed inside the water pipe.

[0019] The top surface of the base plate is provided with placement markings to indicate the accurate placement of the sample. This allows personnel to easily place the sample in the correct position using the placement markings on the base plate.

[0020] The beneficial effects of this invention are as follows: By setting up an injection mechanism and driving it to move circumferentially along the sample via a transport mechanism, epoxy sealant is injected into the gap between specimen I and specimen II, thereby sealing the edges of the specimen with epoxy resin, which facilitates the rapid preparation of the specimen required for the test. Furthermore, by setting up mounting mechanisms at both ends of the base plate, water pipes can be installed inside the epoxy resin after the epoxy resin injection is completed. After the epoxy resin cures, the water pipes can be fixed inside the epoxy resin, further facilitating the subsequent testing process. Attached Figure Description

[0021] Figure 1 A schematic diagram of the overall structure of the auxiliary device for testing cold damage and fracture of dry hot rock provided by the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the base plate, injection mechanism, and transport mechanism in this invention;

[0023] Figure 3 This is a schematic diagram of the injection mechanism in this invention;

[0024] Figure 4 This is a schematic diagram of the structure of the container in this invention;

[0025] Figure 5 This is a schematic diagram of the water pipe installation mechanism in this invention;

[0026] Figure 6 This is a schematic diagram of the water pipe structure in this invention;

[0027] Icons: 1-Base plate, 11-First indicator groove, 12-Second indicator groove, 2-Injection mechanism, 21-Base, 211-Slide groove, 22-Adjusting seat, 221-Slider, 23-Injection cylinder, 24-Container, 241-Sealing cap, 242-Plunger, 25-Drive cylinder, 3-Transport mechanism, 31-Support column, 311-Driven gear, 32-Sprocket, 33-Chain, 34-Rotating assembly, 341- Drive motor, 342-drive gear, 35-fixed seat, 4-water pipe installation mechanism, 41-mounting seat, 42-mounting rod, 43-mounting sleeve, 431-clamping pad, 44-water pipe, 441-sealing adhesive, 442-limiting step, 45-removal part, 451-push-pull rod, 452-push-pull block, 453-hand handle, 5-sample, 51-sample I, 52-sample II, 53-high-strength pad. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The following embodiments are explanations of the present invention, but the present invention is not limited to the following embodiments.

[0029] Example 1 is an auxiliary device for a dry hot rock cold damage fracture test, referring to... Figures 1-6 As shown, the system includes a base plate 1 for placing the sample 5, an injection mechanism 2 for injecting epoxy resin into the gaps of the sample 5, and a transport mechanism 3 for driving the injection mechanism 2 to move circumferentially along the sample 5. After placing the specimen I 51 on the base plate 1, a high-strength pad 53 is placed on the specimen I 51, and then the specimen II 52 is placed on the high-strength pad 53, thus creating a gap between the specimen I 51 and the specimen II 52. By selecting a pad of a specified thickness as needed, a gap of a specified width can be formed between the specimen I 51 and the specimen II 52. Then, epoxy resin is injected at the edge of the gap through the injection mechanism 2. During the injection process, the transport mechanism 3 drives the injection mechanism 2 to move circumferentially along the sample 5, thus sealing the gap between the specimen I 51 and the specimen II 52 around the perimeter, thereby conveniently and quickly preparing the sample 5 into the state required for the test.

[0030] Reference Figure 1 , Figure 2As shown, to facilitate placing the sample 5 at the center of the base plate 1, a placement mark is provided on the top surface of the base plate 1 to indicate the accurate placement of the sample. In this embodiment, the placement mark has a first indicator groove 11 and a second indicator groove 12 formed on the base plate 1. The length direction of the first indicator groove 11 is consistent with the length direction of the base plate 1, and the length direction of the second indicator groove 12 is consistent with the width direction of the base plate 1. Both the first indicator groove 11 and the second indicator groove 12 pass through the center point of the base plate 1. Before placing the sample 5, the center points in the length direction and the width direction of the sample 5 are marked. Then, the corresponding marks are aligned with the first indicator groove 11 and the second indicator groove 12, which ensures that the sample 5 is located at the center of the base plate 1.

[0031] Reference Figure 2 , Figure 3 As shown, the injection mechanism 2 includes a base 21, an adjusting seat 22, an injection cylinder 23, and a container 24. A slider 221 is welded to the bottom of the adjusting seat 22. A groove 211 for sliding the slider 221 is provided on the base 21 along its own length. The injection cylinder 23 is fixedly installed on the adjusting seat 22. The container 24 is fixedly installed on the upper part of the injection cylinder 23 and is connected to the injection cylinder 23. After the epoxy resin is filled into the container 24, the epoxy resin can flow into the injection cylinder 23 under the action of gravity and flow out from the injection port at the end of the injection cylinder 23 into the gap. In order to make the epoxy resin flow more smoothly, the injection cylinder 23 is tilted and the end of the injection cylinder 23 facing the sample 5 is lower than the end of the injection cylinder 23 away from the sample 5. The container 24 is installed on the upper part of the highest point of the injection cylinder 23 so that the epoxy resin entering the injection cylinder 23 can easily flow to the gap between the sample I 51 and the sample II 52.

[0032] By changing the position of the slider 221 along the length of the groove 211, the position of the injection port of the injection cylinder 23 within the gap can be changed. To facilitate precise adjustment of the injection cylinder 23's position, a drive cylinder 25 is fixedly mounted at one end of the base 21. The piston rod of the drive cylinder 25 extends into the groove 211 and is fixedly connected to the slider 221. Activating the drive cylinder 25 moves the slider 221 within the groove 211, thus changing the position of the adjusting seat 22 on the base 21, thereby adjusting the position of the injection cylinder 23. During the injection of epoxy resin, the injection port of the injection cylinder 23 is first moved to the deepest point required for injection. After the transport mechanism 3 moves the injection mechanism 2 one revolution around the sample 5, the injection cylinder 23 is moved a distance away from the sample 5 for a second round of injection, until the edge of the gap is fully injected. Through multiple injections, the epoxy sealant can be injected more evenly into the gap, improving the preparation quality of the sample 5.

[0033] Reference Figure 3 , Figure 4 As shown, a sealing cap 241 is provided at the top of the receiving cylinder. The sealing cap 241 is threaded onto the receiving cylinder for easy installation or removal. The top of the sealing cap 241 has multiple through holes, each equipped with a plunger 242. Removing the plunger 242 from the through hole opens the through hole. By increasing the number of open through holes, the amount of air entering can be changed, thereby altering the discharge speed of the receiving cylinder and ultimately the injection speed of the epoxy resin.

[0034] Reference Figure 2 As shown, the transport mechanism 3 includes support columns 31 rotatably connected to the four corners of the base plate 1. A sprocket 32 ​​is fixedly connected to the top of each support column 31, and a chain 33 is wound around the multiple sprockets 32. A rotating assembly 34 for driving the support column 31 to rotate is provided on the base plate 1, located on one side of one of the support columns 31. A fixed seat 35 is welded to the chain 33, and a base 21 is welded to the fixed seat 35. By rotating one of the support columns 31, the sprocket 32 ​​at the top of the rotating support column 31 can drive the other sprockets 32 to rotate synchronously via the chain 33. During the rotation of the chain 33, the fixed seat 35 can move circumferentially along the sample 5, thereby driving the injection mechanism 2 to move synchronously as a whole via the base 21.

[0035] The rotating assembly 34 in this embodiment includes a drive motor 341, which is fixedly mounted on the base plate 1 via a motor mount. A drive gear 342 is mounted on the output shaft of the drive motor 341, and a driven gear 311 that meshes with the drive gear 342 is welded to the bottom of the support column 31. When the drive motor 341 is started, it drives the drive gear 342 to rotate, which in turn drives the driven gear 311 to rotate synchronously, thereby causing the support column 31 with the driven gear 311 to rotate. In this embodiment, the drive gear 342 and the driven gear 343 are bevel gears that mesh with each other.

[0036] In this embodiment, the support column 31 is a telescopic column with adjustable length. Specifically, the support column 31 consists of a bottom column, a top column, and a plug rod. The bottom column is rotatably mounted on the base plate 1. A slot is provided at the top of the bottom column. The top column is slidably inserted into the slot. The plug rod is radially inserted through the bottom column. Multiple insertion holes are provided on the top column along its own length direction. The plug rod is inserted into one of the insertion holes to fix the position of the top column in the bottom column.

[0037] Reference Figure 1 , Figure 5As shown, both ends of the base plate 1 are provided with water pipe installation mechanisms 4. The water pipe installation mechanism 4 includes a mounting base 41, which is made of magnetic material and can be attracted to the base plate 1. A mounting rod 42 is rotatably connected to the mounting base 41. The end of the mounting rod 42 away from the mounting base 41 is provided with a mounting sleeve 43, and a water pipe 44 is slidably inserted into the mounting sleeve 43. During the epoxy resin injection process, the mounting rod 42 is rotated to a horizontal state to avoid interference with the movement of the injection mechanism 2. After the epoxy resin injection is completed, the mounting rod 42 is rotated to a vertical state, and then the water pipe 44 is inserted from the mounting sleeve 43 into both ends of the gap between specimen I 51 and specimen II 52. After insertion, the mounting rod 42 and the mounting sleeve 43 can support the position of the water pipe 44. After the epoxy resin cures, the water pipe 44 can be fixed in the epoxy resin. Sample 5 is removed and heated to a specified temperature. Then, one water pipe 44 is used as the inlet pipe and the other water pipe 44 is used as the outlet pipe, and the water injection test can be started. To improve the support of the water pipe 44, multiple clamping pads 431 are axially distributed on the inner wall of the mounting sleeve 43. The clamping pads 431 are made of rubber and can improve the stability of the water pipe 44 within the mounting sleeve 43.

[0038] Reference Figure 5 As shown, the mounting rod 42 is an adjustable telescopic rod, comprising a base rod, a top rod, and a positioning bolt. The base rod is rotatably connected to the mounting base 41, the top rod is slidably mounted inside the base rod, and the positioning bolt is threaded onto the rod, with its end abutting against the top rod. For samples 5 of different thicknesses, by adjusting the position of the top rod within the base rod and fixing its position with the positioning bolt, the overall length of the mounting rod 42 can be adjusted to accommodate the thickness of the sample 5.

[0039] Reference Figure 5 , Figure 6 As shown, the end of the water pipe 44 facing the sample 5 is provided with a sealant 441 for sealing the end of the water pipe 44, and a removal part 45 is provided inside the water pipe 44 for removing the sealant 441. The sealant 441 can play a sealing role during the insertion of the water pipe 44 into the epoxy resin adhesive to prevent epoxy resin adhesive from entering the water pipe 44 and causing blockage; the removal part 45 can remove the sealant 441 after the epoxy resin adhesive has cured.

[0040] Reference Figure 6As shown, the removal component 45 includes a push-pull rod 451, a push-pull block 452, and a hand handle 453. The push-pull block 452 is slidably installed inside the water pipe 44, and the circumferential surface of the push-pull block 452 is in contact with the inner wall of the water pipe 44. A limiting step 442 is provided at the end of the water pipe 44 facing the sample 5 to prevent the push-pull block 452 from being removed from the water pipe 44. The push-pull rod 451 is fixedly installed at the end of the push-pull block 452 away from the sample 5, and the hand handle 453 is fixedly installed at the end of the push-pull rod 451 away from the push-pull block 452. During the process of the water pipe 44 entering the epoxy resin adhesive, the push-pull rod 451 is pushed by the hand lever 453 and the push-pull block 452 abuts against the limiting step 442. The push-pull block 452 can play a certain stabilizing role for the sealant 441, and to a certain extent prevent the sealant 441 from sliding into the water pipe 44 under the pressure of the epoxy resin adhesive. When it is necessary to remove the sealant 441, the push-pull rod 451 is pulled outward by the hand lever 453. Under the negative pressure, the sealant 441 can enter the interior of the water pipe 44, and the staff can easily remove the sealant 441.

[0041] The working process of this embodiment is as follows: Specimen I 51 is placed at the center of the base plate 1 by the indication function of the first indicator groove 11 and the second indicator groove 12. Then, a high-strength pad 53 is placed on top of specimen I 51, and specimen II 52 is placed on the high-strength pad 53, creating a gap between specimen I 51 and specimen II 52. Then, epoxy resin is injected at the edge of the gap by the injection mechanism 2. During the injection process, the injection mechanism 2 is moved circumferentially along the specimen 5 by the transport mechanism 3, thus sealing the gap between specimen I 51 and specimen II 52 to prepare the specimen 5 into the state required for the test. After the epoxy resin is injected, the mounting rod 42 is rotated to a vertical position, and then the water pipe 44 is inserted from the mounting sleeve 43 into both ends of the gap in the specimen 5. After insertion, the mounting rod 42 and the mounting sleeve 43 provide support for the position of the water pipe 44. After the epoxy resin cures, the water pipe 44 is fixed within the epoxy resin. Take out sample 5 and heat it to the specified temperature. Then, use one of the water pipes 44 as the inlet pipe and the other water pipe 44 as the outlet pipe to start the water injection test.

[0042] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An apparatus for assisting in dry hot rock cold damage fracture testing, characterized by: Have: The bottom plate (1), the sample is placed on the bottom plate (1), the sample (5) has test piece I (51) placed on the bottom plate (1) and test piece II (52) placed on test piece I (51), there is a gap between test piece I (51) and test piece II (52) due to the placement of a plurality of high-strength cushion blocks (53); Injection mechanism (2) is arranged on the bottom plate (1), used for injecting epoxy resin glue into the gap between test piece I (51) and test piece II (52); Transportation mechanism (3) is installed on the bottom plate (1), the transportation mechanism (3) is fixedly installed with the injection mechanism (2), the transportation mechanism (3) drives the injection mechanism (2) to move along the periphery of the sample (5), used for uniformly injecting the epoxy resin glue into the gap around the sample (5) and sealing the gap around the sample (5); The injection mechanism (2) has a base (21), an injection cylinder (23) and a storage barrel (24), the base (21) is fixedly installed on the transportation mechanism (3) through a fixing seat (35), the storage barrel (24) is installed at the top of the injection cylinder (23), the storage barrel (24) is used for providing the epoxy resin glue for the injection cylinder (23), the injection cylinder (23) is installed on the top surface of the base (21), the injection cylinder (23) is used for injecting the epoxy resin glue into the gap between test piece I (51) and test piece II (52); The bottom plate (1) is installed with a water pipe installation mechanism (4) for burying the water pipe (44) into the epoxy resin glue between test piece I (51) and test piece II (52) at the position of both sides of the sample (5); The water pipe installation mechanism (4) has a mounting seat (41), a mounting rod (42) and a mounting sleeve (43), the mounting rod (42) is a telescopic adjusting mounting rod (42), the mounting seat (41) is fixedly installed on the bottom plate (1), one end of the mounting rod (42) is hingedly connected with the mounting seat (41), the other end of the mounting rod (42) is fixedly installed with the mounting sleeve (43), the clamping pad (431) for clamping the water pipe (44) is installed on the inner wall of the mounting sleeve (43); The water pipe (44) is installed with a sealing adhesive sticker (441) on one end close to the sample (5), the water pipe (44) is installed with a removal piece (45) for taking out the sealing adhesive sticker (441) from the water pipe (44) after burying the water pipe (44) into the epoxy resin glue; The removal piece (45) has a push-pull block (452) arranged in the water pipe (44), the push-pull block (452) is connected with the sealing adhesive sticker (441), the push-pull block (452) is connected with a hand-held rod (453) arranged outside the water pipe (44) away from the sample (5) end through a push-pull rod (451).

2. An apparatus according to claim 1, wherein: A sliding groove (211) is arranged on the base (21) perpendicular to the transportation direction of the transportation mechanism (3), a sliding block (221) is installed in the sliding groove (211) and slides with the sliding groove (211), the sliding block (221) is driven by a driving cylinder (25) fixedly installed on the base (21), the injection cylinder (23) is fixedly connected with the sliding block (221) through an adjusting seat (22).

3. An apparatus according to claim 1, wherein: The containing barrel (24) is provided with an opening at the top, and a plugging cover (241) is installed at the opening through screw thread cooperation, and a plurality of through holes are formed in the plugging cover (241) and plugged by plungers (242).

4. An apparatus according to claim 1, wherein: The transport mechanism (3) is provided with a plurality of support columns (31) arranged on the bottom plate (1) in the direction perpendicular to the top surface of the bottom plate (1), the support columns (31) are telescopic support columns (31), the support columns (31) are rotatably installed on the bottom plate (1) in the axial direction of the support columns (31), a sprocket (32) coaxially arranged with the support columns (31) is fixedly sleeved on the top of the support columns (31), the sprockets (32) on the top of the support columns (31) are driven by the same chain (33), and the sample (5) is placed in the area surrounded by the chain (33).

5. An apparatus according to claim 4, wherein: A driven gear (311) is sleeved on one of the support columns (31), a driving motor (341) is installed on the bottom plate (1), and a driving gear (342) in gear cooperation with the driven gear (311) is installed on the output shaft of the driving motor (341).

6. An apparatus according to claim 1, wherein: The water pipe (44) is provided with a limiting step (442) on the inner wall near the side of the sample (5) for avoiding the push-pull block (452) from moving out of the water pipe (44).

7. An apparatus according to claim 1, wherein: The top surface of the bottom plate (1) is provided with a placement mark for indicating the accurate placement of the sample (5) on the bottom plate (1).

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