Static corrosion device

Abstract

The static corrosion device comprises a barrel, a first sealing piece, a fixing block, a second sealing piece and a cover plate, the barrel is provided with a first end and a second end which are opposite, the first end is an open end, the second end is a closed end, the fixing block is arranged at the open end, the fixing block is provided with a first opening hole in the axial direction of the barrel, and the second sealing piece is arranged in the first opening hole. The first sealing piece is located between the open end and the fixing block, the second sealing piece is arranged between the side, away from the open end, of the fixing block and the sample, and the cover plate is arranged on the side, away from the fixing block, of the sample and connected with the barrel. According to the scheme provided by the invention, the whole device is operated in a closed environment, gas component interference can be avoided, and meanwhile, after the test solution flows to the sample through the first opening, the contact area of the sample and the solution is limited by utilizing the second sealing element, so that the test area of each sample can be accurately controlled, and the consistency of test results is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material testing, in particular to a static corrosion device. BACKGROUND

[0002] Metal static corrosion is a corrosion phenomenon that occurs in metals in a static environment, mainly occurring in static solutions, gases or other media. Metal static corrosion usually occurs in static environments such as static water, acid, base, salt solution or humid air. Its mechanism involves chemical or electrochemical reactions between the metal and the surrounding medium. Metal static corrosion is ubiquitous in many fields. Understanding its principles, influencing factors and preventive measures is crucial for protecting metal materials, prolonging equipment life and ensuring safe operation.

[0003] The static corrosion testing device in the related art cannot accurately control the test area when in use, resulting in inconsistent test results. CONTENT OF THE UTILITY MODEL

[0004] In view of the above problems, the present application provides a static corrosion device, which can solve the problem that the static corrosion testing device cannot accurately control the test area when in use, resulting in inconsistent test results.

[0005] To solve the above technical problems, the present application provides a static corrosion device, comprising:

[0006] A cylinder, which is a transparent cylinder, has opposite first and second ends, the first end is an open end, and the second end is a closed end;

[0007] A first sealing element;

[0008] A fixed block, which is provided at the open end and has a first opening along the axial direction of the cylinder, and the first sealing element is located between the open end and the fixed block;

[0009] A second sealing element, which is provided between the side of the fixed block away from the open end and the sample, and is configured to limit the contact area of the sample and the solution;

[0010] A cover plate, which is provided at the side of the sample away from the fixed block and is connected with the cylinder.

[0011] In the technical solution of this application embodiment, a test solution is introduced into the cylinder, and then the first seal, fixing block, second seal, sample, and cover plate are installed sequentially to ensure no leakage. The cylinder is then rotated 180° and inverted. At this point, the test solution inside the cylinder flows to the sample through the open end and the first opening, and the test begins. The entire device operates in a closed environment, avoiding interference from gas components. Furthermore, after the test solution flows to the sample through the first opening, the second seal limits the contact area between the sample and the solution, thereby precisely controlling the test area of ​​each sample and ensuring the consistency of the test results. Moreover, the second seal ensures a sealed contact with the sample, eliminating the need to seal the sample edges, significantly reducing sample preparation time and effectively improving testing efficiency. Further, since the cylinder is entirely transparent, during the test, only periodic CT scans of the corrosion depth are needed; the sample does not need to be removed, avoiding surface passivation after sample removal, which could affect subsequent test results.

[0012] In some embodiments, a mounting panel is provided at the first end of the cylinder, and a second opening is provided on the mounting panel along the axial direction of the cylinder;

[0013] The cover plate is connected to the mounting panel, and the first sealing element is located between the mounting panel and the fixing block. The solution inside the cylinder flows to the sample through the second opening and the first opening. This facilitates the connection between the cylinder and the cover plate.

[0014] In some embodiments, the mounting panel has a first limiting groove on the side facing the fixing block. The first limiting groove is located around the second opening, and the first sealing element is partially located within the first limiting groove. This facilitates the fixing of the first sealing element.

[0015] In some embodiments, the static etching apparatus further includes fasteners configured to secure the cover plate to the mounting panel. This facilitates the connection of the cover plate and the mounting panel together.

[0016] In some embodiments, the mounting panel has a first mounting hole, and the cover plate has a second mounting hole, with the fastener passing through the first mounting hole and the second mounting hole. This facilitates the connection between the fastener and the mounting panel and the cover plate.

[0017] In some embodiments, the fixing block has a second limiting groove on the side facing the cover plate, the second limiting groove being located around the first opening, and the second sealing element being partially located within the first opening. This facilitates the fixing of the second sealing element.

[0018] In some embodiments, the first opening is a first circular hole, or the first opening is a second circular hole, or the first opening is a square hole, wherein the first circular hole and the second circular hole have different diameters.

[0019] In some embodiments, the inner wall of the barrel is provided with a corrosion-resistant layer, and / or the inner wall of the first opening is provided with a corrosion-resistant layer. In this way, the test solution can be prevented from corroding the inner wall of the barrel or the first opening.

[0020] In some embodiments, the side of the mounting panel facing the cover plate is provided with a protrusion or a clamping groove, and the side of the cover plate facing the mounting panel is provided with a clamping groove or a protrusion.

[0021] Under the condition that the cover plate and the mounting panel are connected, the protrusion and the clamping groove are matched. In this way, the cover plate and the mounting panel can be tightly connected together, effectively improving the sealing performance of the overall device.

[0022] In some embodiments, the side of the cover plate facing the sample is provided with a protrusion, and under the condition that the cover plate and the barrel are connected, the protrusion abuts against the side of the sample away from the fixing block. In this way, the sample can be stably fixed between the cover plate and the fixing block.

[0023] The above description is only a summary of the technical solutions of the present application. In order to enable the technical means of the present application to be more clearly understood, and to be implemented according to the content of the description, and in order to enable the above and other purposes, features and advantages of the present application to be more apparent and easy to understand, the following specific embodiments of the present application are described in detail. BRIEF DESCRIPTION OF DRAWINGS

[0024] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the embodiments. The accompanying drawings are included to provide a description of the embodiments and are not meant to limit the scope of the present application. Moreover, the same reference numerals in the attached drawings indicate the same or similar elements. In the drawings:

[0025] Figure 1 A structural schematic diagram of a static corrosion device provided by some embodiments of the present application is shown in the figure;

[0026] Figure 2 A structural schematic diagram of another static corrosion device provided by some embodiments of the present application is shown in the figure;

[0027] Figure 3 A sectional view of Figure 2 is shown in the figure;

[0028] Figure 4 A barrel schematic diagram provided by some embodiments of the present application is shown in the figure;

[0029] Figure 5 A fixed block diagram provided for some embodiments of the present application;

[0030] Figure 6 Another fixed block diagram provided for some embodiments of the present application;

[0031] Figure 7 Still another fixed block diagram provided for some embodiments of the present application.

[0032] Reference signs in the detailed description of the embodiments are as follows:

[0033] 10, barrel; 101, mounting panel; 1011, second opening; 1012, first limiting groove; 1013, first mounting hole; 11, first sealing member; 12, fixed block; 121, first opening; 122, second limiting groove; 13, second sealing member; 14, cover plate; 141, second mounting hole; 15, sample. DETAILED DESCRIPTION

[0034] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion.

[0036] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0037] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0038] In the description of the embodiments of the present application, the term "and / or" is only to describe the relationship between the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0039] In the description of the embodiments of the present application, the term "a plurality of" refers to two or more (including two), and similarly, "a plurality of groups" refers to two or more groups (including two groups), and "a plurality of pieces" refers to two or more pieces (including two pieces).

[0040] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the embodiments of the present application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0041] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0042] Metal static corrosion is a corrosion phenomenon that occurs in a static environment, mainly occurring in static solutions, gases or other media. Metal static corrosion usually occurs in a static environment, such as static water, acid, base, salt solution or humid air. Its mechanism involves chemical or electrochemical reactions between the metal and the surrounding medium. Metal static corrosion is ubiquitous in many fields. Understanding its principles, influencing factors and preventive measures is crucial for protecting metal materials, prolonging equipment life and ensuring safe operation.

[0043] In the related art, the static corrosion testing device needs to process the sample first, prepare the sample according to the relevant standard, polish, clean and dry the surface of the sample to ensure that the surface is free of dirt or oxidation layer, and use crystal glue or structural glue to perform edge sealing treatment on the metal sample to be tested. The sample sealed by crystal glue needs to be polished to expose the test surface.

[0044] Because the test sample is sealed by the structural glue, the flowability of the glue cannot accurately control the test area, resulting in inconsistent test areas among multiple parallel samples, which easily leads to inconsistent test results.

[0045] Based on the above considerations, in order to solve the problem that the static corrosion testing device cannot accurately control the test area during use, leading to inconsistent test results, a static corrosion device is designed. The device includes a cylinder, a first sealing element, a fixed block, a second sealing element, and a cover plate. The cylinder is a transparent cylinder, and has opposite first and second ends. The first end is an open end, and the second end is a closed end. The fixed block is arranged at the open end, and has a first opening along the axial direction of the cylinder. The first sealing element is located between the open end and the fixed block. The second sealing element is arranged between the fixed block and the sample on the side away from the open end, and is configured to limit the contact area of the sample and the solution. The cover plate is arranged on the side of the sample away from the fixed block, and is connected to the cylinder.

[0046] In the technical solution of the present application, the test solution is introduced into the cylinder, and then the first sealing element, the fixed block, the second sealing element, the sample, and the cover plate are sequentially installed to ensure that there is no leakage. Then the cylinder is rotated 180° and turned over. At this time, the test solution in the cylinder flows through the open end and the first opening to the sample and starts testing. The overall device is tested in a closed environment, which can avoid interference from gas components. At the same time, after the test solution flows through the first opening to the sample, the second sealing element is used to limit the contact area of the sample and the solution, so that the test area of each sample can be accurately controlled, ensuring the consistency of the test results. Moreover, the second sealing element is in sealing contact with the sample, so there is no need to close the edges of the sample, greatly reducing the sample preparation time and effectively improving the test efficiency. Furthermore, since the entire cylinder is a transparent cylinder, during testing, only the corrosion depth needs to be observed periodically using CT, and the sample does not need to be removed, avoiding surface passivation after the sample is removed, which affects the subsequent test results.

[0047] According to some embodiments of the present application, Figure 1 is a structural diagram of a static corrosion device in the present application, Figure 2 is a structural diagram of another static corrosion device in the present application, Figure 3 is a sectional view. As Figure 2 , Figure 1 and in combination with Figure 2 , Figure 3As shown, the application provides a static corrosion device, which comprises a barrel 10, a first sealing element 11, a fixed block 12, a second sealing element 13 and a cover plate 14, wherein the barrel 10 is a transparent barrel, the barrel 10 has opposite first and second ends, the first end is an open end, the second end is a closed end, the fixed block 12 is arranged at the open end, the fixed block 12 is provided with a first opening 121 along the axial direction of the barrel 10, the first sealing element 11 is located between the open end and the fixed block 12, the second sealing element 13 is arranged between the side of the fixed block 12 away from the open end and the sample 15, the second sealing element 13 is configured to limit the contact area of the sample 15 and the solution, and the cover plate 14 is arranged on the side of the sample 15 away from the fixed block 12 and connected with the barrel 10.

[0048] The barrel 10 in the embodiment can be formed of glass, acrylic or the like, which can be determined according to actual conditions, and the embodiment of the present application does not limit this.

[0049] In the embodiment, the fixed block 12 blocks the open end of the barrel 10, and the first opening 121 on the fixed block 12 is in communication with the inside of the barrel 10.

[0050] The first sealing element 11 and the second sealing element 13 can both be annular sealing rings, the first sealing element 11 can ensure the sealing property of the fixed block 12 and the open end, and the second sealing element 13 can ensure the sealing property between the fixed block 12 and the sample 15.

[0051] Meanwhile, when the test solution in the barrel 10 flows through the first opening 121 to the side of the sample 15 facing the fixed block 12, the test solution can only react with the sample 15 in the area defined by the second sealing element 13 and the sample 15 when they are in close contact, effectively ensuring the consistency of the test area.

[0052] The cover plate 14 in the embodiment can be connected with the barrel 10 by bolts or clamping, which can be determined according to actual conditions, and the embodiment of the present application does not limit this.

[0053] When testing, first, introduce the test solution into the barrel 10, then install the first sealing element 11, the fixed block 12, the second sealing element 13, the sample 15 and the cover plate 14 in sequence, ensure that there is no liquid leakage, then rotate the barrel 10 by 180° and turn it upside down, at this time, the test solution in the barrel 10 flows through the open end and the first opening 121 to the sample 15 and starts testing.

[0054] The whole device is carried out in a closed environment, so that the gas components can be avoided from interfering, and meanwhile, after the test solution flows to the sample 15 through the first opening 121, the second sealing member 13 is used to limit the contact area of the sample 15 and the solution, so that the test area of each sample 15 can be accurately controlled, and the consistency of the test results is ensured; and the second sealing member 13 is in sealing contact with the sample 15, so that the edge of the sample 15 does not need to be closed, which greatly reduces the sample preparation time of the sample 15 and effectively improves the test efficiency; further, since the whole cylinder body 10 is a transparent cylinder body 10, during the test, the corrosion depth only needs to be observed by CT at regular time, and the sample 15 does not need to be taken out, so that the surface passivation of the sample 15 after being taken out is avoided, and the subsequent test results are affected.

[0055] According to some embodiments of the present application, as shown in Figure 1 and in combination with Figure 4 It is shown that the first end of the cylinder body 10 is provided with a mounting panel 101, and the mounting panel 101 is provided with a second opening 1011 in the axial direction of the cylinder body 10; the cover plate 14 is connected with the mounting panel 101, the first sealing member 11 is located between the mounting panel 101 and the fixed block 12, and the solution in the cylinder body 10 flows to the sample 15 through the second opening 1011 and the first opening 121.

[0056] The mounting panel 101 in the embodiment is integrally formed with the cylinder body 10. By providing the mounting panel 101 at the first end, the cylinder body 10 and the cover plate 14 can be conveniently connected together.

[0057] According to some embodiments of the present application, as shown in Figure 4 and in combination with Figure 1 It is shown that the side of the mounting panel 101 facing the fixed block 12 is provided with a first limiting groove 1012, and the first limiting groove 1012 is located at the periphery of the second opening 1011, and meanwhile, the first sealing member 11 is partially located in the first limiting groove 1012. In this way, the first sealing member 11 is conveniently fixed.

[0058] The first limiting groove 1012 in the embodiment is located at the periphery of the second opening 1011, and when the first sealing member 11 is placed in the first limiting groove 1012, the first sealing member 11 partially protrudes from the first limiting groove 1012. After the fixed block 12 is installed on the mounting panel 101, the first sealing member 11 and the side of the fixed block 12 facing the mounting panel 101 abut.

[0059] The first limiting groove 1012 is provided in the embodiment, so that the first sealing member 11 is conveniently fixed between the mounting panel 101 and the fixed block 12, and the first sealing member 11 is avoided from moving.

[0060] According to some embodiments of the present application, the static corrosion device further comprises a fastener (not labeled in the figure) configured to fasten the cover plate 14 and the mounting panel 101.

[0061] The fastener in the embodiment can be a bolt, a pin shaft, etc., which will not be described here.

[0062] The embodiment sets the fastener, so that the cover plate 14 and the mounting panel 101 can be conveniently connected together.

[0063] According to some embodiments of the present application, as shown in Figure 1 , the mounting panel 101 is provided with a first mounting hole 1013, and the cover plate 14 is provided with a second mounting hole 141, and the fastener is arranged in the first mounting hole 1013 and the second mounting hole 141.

[0064] The first mounting hole 1013 and the second mounting hole 141 in the embodiment can be threaded holes, and the fastener is a bolt. In use, the mounting panel 101 and the cover plate 14 can be conveniently connected together by the bolt passing through the corresponding threaded hole.

[0065] According to some embodiments of the present application, as shown in Figure 1 , the side of the fixed block 12 facing the cover plate 14 is provided with a second limiting groove 122, the second limiting groove 122 is located at the periphery of the first opening 121, and the second sealing member 13 is partially located in the first opening 121.

[0066] The second limiting groove 122 in the embodiment is located at the periphery of the first opening 121. When the second sealing member 13 is placed in the second limiting groove 122, the second sealing member 13 partially protrudes from the second limiting groove 122. After the sample 15 is placed on the side of the fixed block 12 away from the mounting panel 101, the second sealing member 13 abuts against the corresponding sample 15.

[0067] The embodiment sets the second limiting groove 122, so that the second sealing member 13 can be conveniently fixed on the fixed block 12, and the second sealing member 13 is prevented from moving.

[0068] According to some embodiments of the present application, as shown in Figure 5 and in combination with Figure 6 , Figure 7 , the first opening 121 is a first circular hole, or the first opening 121 is a second circular hole, or the first opening 121 is a square hole, wherein the diameters of the first circular hole and the second circular hole are different.

[0069] As shown in Figure 5 , the diameter of the first opening 121 can be 10mm-12mm; as shown in Figure 6 , the diameter of the first opening 121 can be 2mm-4mm; as shown in Figure 7As shown, the first opening 121 can be a square hole.

[0070] The fixed block 12 is made into a standard part in this embodiment, and different test area requirements do not require the design and production of different static corrosion devices, but only need to replace different fixed blocks 12. Since the fixed block 12 is simple to produce and low in cost, the overall device cost and production difficulty are greatly reduced, and the test efficiency is also improved.

[0071] According to some embodiments of the present application, the inner wall of the barrel 10 is provided with a corrosion-resistant layer, and / or the inner wall of the first opening 121 is provided with a corrosion-resistant layer.

[0072] The corrosion-resistant layer can be a glass layer, a pp layer, etc., and the specific type can be determined according to actual conditions, which is not limited in the embodiments of the present application.

[0073] The corrosion-resistant layer of the present embodiment can be a glass layer, a pp layer, etc., and the specific type can be determined according to actual conditions, which is not limited in the embodiments of the present application.

[0074] The present embodiment sets a corrosion-resistant layer on the inner wall of the barrel 10 and the inner wall of the first opening 121, so as to avoid corrosion of the barrel 10 or the inner wall of the first opening 121 by the test solution.

[0075] According to some embodiments of the present application, the side of the mounting panel 101 facing the cover plate 14 is provided with a protrusion or a clamping groove, and the side of the cover plate 14 facing the mounting panel 101 is provided with a clamping groove or a protrusion; under the condition that the cover plate 14 and the mounting panel 101 are connected, the protrusion and the clamping groove are matched.

[0076] The present embodiment can tightly connect the cover plate 14 and the mounting panel 101 together through the matching of the protrusion and the clamping groove, thereby effectively improving the sealing performance of the overall device.

[0077] According to some embodiments of the present application, the side of the cover plate 14 facing the sample 15 is provided with a protrusion, and under the condition that the cover plate 14 and the barrel 10 are connected, the protrusion abuts against the side of the sample 15 away from the fixed block 12.

[0078] In this way, after the overall device is fixed, the sample 15 can be stably positioned between the cover plate 14 and the fixed block 12 under the resistance of the protrusion.

[0079] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some or all of the technical features can be replaced equivalently. Such modifications or replacements do not change the essence of the corresponding technical solutions, which should be covered in the scope of the present application. In particular, the technical features mentioned in each embodiment can be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A static corrosion device, characterized in that, The static corrosion device comprises: a barrel body, which is a transparent barrel body, has opposite first and second ends, the first end is an open end, and the second end is a closed end; a first sealing member; a fixed block, which is arranged at the open end and is provided with a first opening along the axial direction of the barrel body, and the first sealing member is located between the open end and the fixed block; a second sealing member, which is arranged between the side of the fixed block away from the open end and a sample, and is configured to limit the contact area of the sample and a solution; a cover plate, which is arranged on the side of the sample away from the fixed block and is connected with the barrel body.

2. The static corrosion device of claim 1, wherein, The first end of the barrel body is provided with a mounting panel, and the mounting panel is provided with a second opening along the axial direction of the barrel body; the cover plate is connected with the mounting panel, the first sealing member is located between the mounting panel and the fixed block, and the solution in the barrel body flows to the sample through the second opening and the first opening.

3. The static corrosion device of claim 2, wherein, The side of the mounting panel facing the fixed block is provided with a first limiting groove, and the first limiting groove is located at the periphery of the second opening, and part of the first sealing member is located in the first limiting groove.

4. The static corrosion device of claim 2, wherein, The static corrosion device further comprises a fastener configured to fasten the cover plate and the mounting panel.

5. The static corrosion device of claim 4, wherein, The mounting panel is provided with a first mounting hole, the cover plate is provided with a second mounting hole, and the fastener is arranged in the first mounting hole and the second mounting hole.

6. The static corrosion device of claim 1, wherein, The side of the fixed block facing the cover plate is provided with a second limiting groove, and the second limiting groove is located at the periphery of the first opening, and part of the second sealing member is located in the first opening.

7. The static corrosion apparatus according to any one of claims 1 to 6, characterized in that The first opening is a first circular hole, or the first opening is a second circular hole, or the first opening is a square hole, wherein the diameters of the first circular hole and the second circular hole are different.

8. The static corrosion apparatus according to any one of claims 1 to 6, characterized in that The inner wall of the barrel body is provided with a corrosion-resistant layer, and / or the inner wall of the first opening is provided with a corrosion-resistant layer.

9. The static corrosion apparatus according to any one of claims 2 to 5, characterized in that The side of the mounting panel facing the cover plate is provided with a protrusion or a clamping groove, and the side of the cover plate facing the mounting panel is provided with a clamping groove or a protrusion; Under the condition that the cover plate is connected with the mounting panel, the protrusion cooperates with the clamping groove.

10. The static corrosion apparatus according to any one of claims 1 to 6, characterized in that The side of the cover plate facing the sample is provided with a protrusion, and under the condition that the cover plate is connected with the barrel body, the protrusion abuts against the side of the sample away from the fixed block.

Images