Clamp for high-temperature tensile test of metal pipe

Abstract

The utility model relates to the field of clamps, and discloses a clamp for a high-temperature tensile test of a metal pipe, which comprises a sample and is characterized in that a clamping structure is arranged on the outer wall of the sample, the clamping structure comprises a conical jacket, a pressing block is arranged on the end face of the conical jacket, a threaded ejector rod is arranged on the outer wall of the pressing block, and the threaded ejector rod is connected with the conical jacket. The outer wall of the threaded ejector rod is sleeved with a shell, the outer surface of the shell is in threaded connection with a connecting rod, a positioning opening is formed in the outer wall of the pressing block, a mounting assembly is arranged in the shell, a connecting assembly is arranged on the surface of the connecting rod, and the outer surface of the conical clamping sleeve is of a conical structure. The conical jacket is composed of four groups of semicircular bodies, and cavities are formed in the inner surfaces of the semicircular bodies. According to the keyless coupling device disclosed by the utility model, the clamping structure is arranged, and the pressure and friction force generated between the containing surfaces are utilized to realize load transmission by utilizing the principle of the expansion sleeve, so that the test accuracy is ensured.

Description

Technical Field

[0001] The utility model relates to the field of clamps, in particular to a clamp for high-temperature tensile testing of metal pipes. Background Art

[0002] Metal pipes require high-temperature tensile testing primarily because it can help evaluate the mechanical properties of metal materials in high-temperature environments, including the specific impact on strength, deformation, and elastic modulus. By conducting tensile tests at temperatures above room temperature, the tensile deformation and stress-strain curves of the material after high temperature can be obtained, allowing analysis of the impact of different temperatures on material properties.

[0003] After searching, Chinese patent announcement number: CN110806348A discloses a fixture and method suitable for high-temperature tensile testing of small-sized metal pipes. It adopts a circular embracing clamping method. The tooling chuck part consists of a fixture sleeve, a clamping cone and a top cone. The test piece is locked in the chuck by squeezing the clamping cone and the top cone. This locking force is far greater than the load applied to the test piece during high-temperature stretching, and there will be no slipping or root breakage during the test.

[0004] In the above technical solution, a circular ring clamping method is used to clamp and lock the sample. During the high-temperature tensile test of the pipe, the circular ring clamping method can easily cause the pipe to rotate after clamping, thereby reducing the reliability and firmness of the connection between the pipe and the clamp. Therefore, a clamp for high-temperature tensile testing of metal pipes is proposed to solve the above problem. Utility Model Content

[0005] In order to make up for the above shortcomings, the utility model provides a clamp for high-temperature tensile testing of metal pipes, which aims to improve the problem in the existing technology that the clamp for high-temperature tensile testing of metal pipes cannot generate pressure and friction between the clamp and the containing surface of the pipe to ensure clamping stability.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions: a fixture for high-temperature tensile testing of metal pipes, comprising a specimen, the outer wall of the specimen is provided with a clamping structure, the clamping structure comprises a conical jacket, the end face of the conical jacket is provided with a pressure block, the outer wall of the pressure block is provided with a threaded push rod, the outer wall of the threaded push rod is provided with an outer shell, the outer surface of the outer shell is threadedly connected to a connecting rod, the outer wall of the pressure block is provided with a positioning port, the interior of the outer shell is provided with an installation component, and the surface of the connecting rod is provided with a connecting component.

[0007] As a further description of the above technical solution:

[0008] The outer wall of the sample is provided with a heating device, and the interior of the heating device is provided with a silicon carbide heating body.

[0009] As a further description of the above technical solution:

[0010] The outer surface of the conical jacket is arranged in a conical structure. The conical jacket is composed of four groups of semicircular bodies. The inner surfaces of the semicircular bodies are provided with cavities.

[0011] As a further description of the above technical solution:

[0012] The threaded push rod includes a cylindrical structure, an outer wall of the cylindrical structure is provided with an external thread, and the outer wall of the cylindrical structure is fixedly connected to a hexagonal structure.

[0013] As a further description of the above technical solution:

[0014] The mounting assembly includes an inner cavity, the inner wall of the shell is threadedly connected with a boss cylinder, the outer wall of the shell is provided with a rectangular opening, and the inner wall of the shell is provided with a conical cavity.

[0015] As a further description of the above technical solution:

[0016] The connecting assembly includes symmetrical flat grooves, a pin hole is provided on the surface of the connecting rod, an internal thread is provided on the inner wall of the connecting rod, and a circular cavity is provided on the inner wall of the connecting rod.

[0017] As a further description of the above technical solution:

[0018] The outer wall of one end of the cylindrical structure away from the hexagonal structure is plugged into the inner wall of the positioning opening.

[0019] As a further description of the above technical solution:

[0020] The inner wall of the circular cavity is adapted to the outer wall of the threaded ejector rod.

[0021] The utility model has the following beneficial effects:

[0022] 1. In the utility model, a conical jacket is provided with a housing, a threaded push rod, a connecting rod, a pressure block, a connecting assembly and a mounting assembly to clamp the two ends of the sample, thereby facilitating high-temperature tensile testing of the sample. A keyless connection device is provided by utilizing the principle of an expansion sleeve to realize load transmission by the pressure and friction generated between the containing surfaces, thereby avoiding the risk of the sample being deflected or detached during the test and ensuring the accuracy of the sample test.

[0023] 2. In the present invention, a heating device and a silicon carbide heating body are provided to heat the central area of ​​the sample to ensure that the sample is located in the central area when it breaks during the high temperature test, thereby ensuring the stability of the sample clamping. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the external structure of a fixture for high-temperature tensile testing of metal pipes proposed in the present invention;

[0025] Figure 2 This is a schematic cross-sectional view of the main structure of a fixture for high-temperature tensile testing of metal pipes proposed in the present invention;

[0026] Figure 3 This is a side view schematic diagram of the outer shell structure of a fixture for high-temperature tensile testing of metal pipes proposed by the present invention;

[0027] Figure 4 This is a schematic diagram of the structure of a conical jacket of a fixture for high-temperature tensile testing of metal pipes proposed in the present invention;

[0028] Figure 5 This is a schematic diagram of the pressing block structure of a fixture for high-temperature tensile testing of metal pipes proposed in the utility model;

[0029] Figure 6 This is a schematic diagram of the threaded push rod structure of a fixture for high-temperature tensile testing of metal pipes proposed in the utility model;

[0030] Figure 7 The utility model provides a schematic diagram of the connecting rod structure of a fixture for high-temperature tensile testing of metal pipes.

[0031] Legend:

[0032] 1. Conical jacket; 2. Pressure block; 3. Threaded push rod; 4. Outer shell; 5. Connecting rod; 6. Heating device; 7. Specimen; 101. Semicircular body; 102. Cavity; 103. Positioning port; 104. Cylindrical structure; 105. External thread; 106. Hexagonal structure; 107. Inner cavity; 108. Boss cylinder; 109. Rectangular opening; 110. Conical chamber; 112. Symmetrical flat groove; 113. Pin hole; 114. Internal thread; 115. Circular cavity; 116. Silicon carbide heating element. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0034] Reference Figure 1 、 Figure 3-Figure 5The utility model provides an embodiment: a fixture for high-temperature tensile testing of metal pipes, including a specimen 7, an outer wall of the specimen 7 is provided with a clamping structure, the clamping structure includes a conical jacket 1, the outer shape structure of the conical jacket 1 is 12°, the internal cavity structure of the conical jacket 1 is 12°, the end face of the conical jacket 1 is provided with a pressing block 2, the outer wall of the pressing block 2 is provided with a threaded push rod 3, the outer wall of the threaded push rod 3 is provided with an outer shell 4, the outer surface of the outer shell 4 is threadedly connected with a connecting rod 5, the outer wall of the pressing block 2 is provided with a positioning port 103, the positioning port 103 is arranged at one end of the pressing block 2 close to the threaded push rod 3, the interior of the outer shell 4 is provided with a mounting component, and the surface of the connecting rod 5 is provided with a connecting component.

[0035] Reference Figure 4-Figure 7 The outer surface of the conical jacket 1 is set in a conical structure. The conical jacket 1 is composed of four groups of semicircular bodies 101. The inner surface of the semicircular body 101 is provided with a cavity 102. The interior of the cavity 102 is provided with several groups of equidistantly arranged saw teeth, which are convenient for clamping and fixing the sample 7. The threaded mandrel 3 includes a cylindrical structure 104. The outer wall of the cylindrical structure 104 is provided with an external thread 105. The outer wall of the cylindrical structure 104 is fixedly connected with a hexagonal structure 106. The outer wall of the cylindrical structure 104 away from the hexagonal structure 106 is plugged into the inner wall of the positioning port 103. The cylindrical structure 104, the external thread 105 and the hexagonal structure 106 constitute the threaded mandrel 3 as a whole. The mounting assembly includes an inner cavity 107. The inner wall of the outer shell 4 is threadedly connected with a boss cylinder 108. The inner cavity 107 and the boss The table cylinders 108 are all provided with a threaded structure, and the threaded push rod 3 is screwed into the inner cavity 107 by threads to apply pressure to the pressure block 2. The outer wall of the shell 4 is provided with a rectangular opening 109, and the conical jacket 1 is thus installed in the shell 4. The inner wall of the shell 4 is provided with a conical chamber 110, and the conical jacket 1 is pressed into the conical chamber 110 through the threaded push rod 3 and the pressure block 2 to clamp the sample 7. The connecting component includes symmetrical flat grooves 112, and the surface of the connecting rod 5 is provided with a pin hole 113. The pin hole 113 is located at the center of the symmetrical flat groove 112 and is used for aligning the connecting rod 5 with the external equipment end. The inner wall of the connecting rod 5 is provided with an internal thread 114, and the inner wall of the connecting rod 5 is provided with a circular cavity 115. The inner wall of the circular cavity 115 is adapted to the outer wall of the threaded push rod 3 to accommodate the leaking part of the threaded push rod 3.

[0036] Reference Figure 2 The outer wall of the sample 7 is provided with a heating device 6, and the interior of the heating device 6 is provided with a silicon carbide heating body 116. The heating device 6 is placed in the middle area of ​​the sample 7. The built-in silicon carbide heating body 116 only heats the middle position of the sample 7. This heating method can also ensure that the fracture position of the sample 7 is in the middle.

[0037] Working principle: The conical jacket 1 is installed into the interior of the shell 4 through the rectangular opening 109. The conical chamber 110 provides a certain degree of limiting function for the conical jacket 1. After the pressure block 2 is placed into the interior of the shell 4, the sample 7 is inserted into the interior of the shell 4 so that it enters the center of the four groups of semicircular bodies 101. The threaded push rod 3 is then rotated into the shell 4 to connect the cylindrical structure 104 with the positioning port 103. The hexagonal structure 106 is rotated with a wrench. When the cylindrical structure 104 is subjected to force, it will squeeze the pressure block 2 and thus apply force to the conical jacket 1. After the four groups of semicircular bodies 101 are subjected to force, they expand outward toward one end of the sample 7 due to the limitation of the conical chamber 110. The serrations inside the cavity 102 are aligned with the surface of the sample 7. The surface contact is used to clamp and limit it, and the connecting rod 5 is aligned with the shell 4 and rotated. After the two are threadedly connected, the clamping of one end of the sample 7 is completed. Repeat the above steps to clamp the other end of the sample 7. Finally, the symmetrical flat groove 112 and the pin hole 113 are used to align the two groups of connecting rods 5 with the external equipment end, and then the heating device 6 is placed at the center of the sample 7. The silicon carbide heating body 116 is used to contact the surface of the sample 7 to heat it. During the heating process, the external equipment end can pull the two groups of connecting rods 5 to the opposite side, which is convenient for fixing the sample 7 and ensuring that the sample 7 will not be displaced or fall off under high temperature and tensile force, thereby ensuring the accuracy and safety of the test.

[0038] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent replacements for some of the technical features therein. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A fixture for high-temperature tensile testing of metal pipes, comprising a specimen (7), characterized in that: The outer wall of the sample (7) is provided with a clamping structure, and the clamping structure includes a conical sleeve (1), the end face of the conical sleeve (1) is provided with a pressure block (2), the outer wall of the pressure block (2) is provided with a threaded push rod (3), the outer wall of the threaded push rod (3) is provided with a shell (4), the outer surface of the shell (4) is threadedly connected to a connecting rod (5), the outer wall of the pressure block (2) is provided with a positioning port (103), the interior of the shell (4) is provided with a mounting assembly, and the surface of the connecting rod (5) is provided with a connecting assembly.

2. A fixture for high-temperature tensile testing of metal pipes according to claim 1, characterized in that: The outer wall of the sample (7) is provided with a heating device (6), and the interior of the heating device (6) is provided with a silicon carbide heating body (116).

3. The fixture for high-temperature tensile testing of metal pipes according to claim 1, characterized in that: The outer surface of the conical jacket (1) is arranged in a conical structure. The conical jacket (1) is composed of four groups of semicircular bodies (101). The inner surfaces of the semicircular bodies (101) are provided with cavities (102).

4. The fixture for high-temperature tensile testing of metal pipes according to claim 1, characterized in that: The threaded push rod (3) comprises a cylindrical structure (104), the outer wall of the cylindrical structure (104) is provided with an external thread (105), and the outer wall of the cylindrical structure (104) is fixedly connected with a hexagonal structure (106).

5. The fixture for high-temperature tensile testing of metal pipes according to claim 1, characterized in that: The mounting assembly includes an inner cavity (107), the inner wall of the outer shell (4) is threadedly connected with a boss cylinder (108), the outer wall of the outer shell (4) is provided with a rectangular opening (109), and the inner wall of the outer shell (4) is provided with a conical chamber (110).

6. The fixture for high-temperature tensile testing of metal pipes according to claim 1, characterized in that: The connecting assembly includes a symmetrical flat groove (112), a pin hole (113) is provided on the surface of the connecting rod (5), an internal thread (114) is provided on the inner wall of the connecting rod (5), and a circular cavity (115) is provided on the inner wall of the connecting rod (5).

7. The fixture for high-temperature tensile testing of metal pipes according to claim 4, characterized in that: The outer wall of one end of the cylindrical structure (104) away from the hexagonal structure (106) is plugged into the inner wall of the positioning opening (103).

8. The fixture for high-temperature tensile testing of metal pipes according to claim 6, characterized in that: The inner wall of the circular cavity (115) is adapted to the outer wall of the threaded push rod (3).

Images