Hoop tensile test device and tensile test method

Abstract

The present invention discloses a circumferential tensile test device and a tensile test method, wherein the circumferential tensile test device comprises: a fixed seat and at least one group of tensile mechanisms, each group of tensile mechanisms comprises a connecting assembly and a tensile assembly, the connecting assembly is connected to the fixed seat, the tensile assembly comprises a plurality of tensile assemblies, the plurality of tensile assemblies are arranged at intervals along the circumference of the connecting assembly, the tensile assembly comprises a stress loading member and a driving member, the stress loading member is suitable for abutting against the test piece, the driving member is arranged on the connecting assembly, the output end of the driving member is connected to the stress loading member, and the driving member is used to drive the stress loading member to apply stress to the test piece. The circumferential tensile test device of the embodiment of the present invention, by setting a plurality of tensile assemblies, can drive the stress loading member to apply stress to the test piece through the driving member in the tensile assembly when testing the circumferential tensile performance of the test piece, so as to realize automatic testing of the circumferential tensile performance of the test piece, and the test stability is high and the test result is reliable.

Description

Technical Field

[0001] The invention belongs to the technical field of material performance testing, and in particular relates to a circumferential tensile testing device and a tensile testing method. Background Art

[0002] Pipes, especially round pipes, are often used as material transportation pipelines in industries such as oil and gas transportation, chemical industry, and drainage due to their excellent performance and convenient processing.

[0003] When transporting materials, the circular tube must withstand the pressure generated by the internal transport fluid (liquid, gas). This pressure will cause the circular tube to produce circumferential tension. When the circumferential tension of the circular tube exceeds the strength of its material, the circular tube will be damaged. Therefore, the common failure mode of the circular tube is usually explosive failure caused by the circumferential tension exceeding the strength of its material.

[0004] In the prior art, in order to test the circumferential tensile performance of a circular tube, water pressure test, separation disk test, slice tensile test and other tests are usually used. Water pressure test and separation disk test are mainly applicable to the circumferential performance test of a small-sized circular tube, but cannot be used to test the circumferential performance of a large-sized circular tube, and have a narrow scope of application; the slice tensile test can be applied to the circumferential performance test of a large-sized circular tube, but it requires cutting and opening the circular tube, which causes certain damage to the circular tube. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a circumferential tensile test device, which can perform circumferential tensile performance tests on pipes of different sizes, has a wide range of applications, and does not require the pipe to be opened, thereby solving the technical problems of the circumferential tensile test device in the prior art having a narrow range of applications and causing certain damage to the round pipe during the test.

[0006] The present invention also aims to provide a tensile testing method having the above-mentioned circumferential tensile testing device.

[0007] A circumferential tensile testing device according to an embodiment of the present invention includes: a fixed seat; at least one group of tensile mechanisms, each group of the tensile mechanisms includes: a connecting assembly, the connecting assembly is connected to the fixed seat; a tensile assembly, the tensile assembly includes a plurality of tensile assemblies, and the plurality of tensile assemblies are arranged at intervals along the circumference of the connecting assembly; the tensile assembly includes: a stress loading member, the stress loading member is suitable for abutting against a test piece; a driving member, the driving member is arranged on the connecting assembly, the output end of the driving member is connected to the stress loading member, and the driving member is used to drive the stress loading member to apply stress to the test piece.

[0008] According to the circumferential tensile test device of the embodiment of the present invention, by setting a plurality of tensile components and the plurality of tensile components are arranged at intervals along the circumference of the connecting component, when testing the circumferential tensile performance of the test piece, the stress loading component can be driven by the driving component in the tensile component to apply stress to the test piece to achieve automatic testing of the circumferential tensile performance of the test piece. Since the circumferential tensile test device of the present application connects the stress loading component to the output end of the driving component, the present application can test test pieces of different sizes, thereby improving the scope of application of the circumferential tensile test device of the present application. The circumferential tensile test device of the present application has a wide scope of application, high test stability and reliable test results.

[0009] According to the circumferential tensile testing device of one embodiment of the present invention, the connecting assembly includes a connecting shaft, the tensile mechanism includes a plurality of groups, and the connecting shafts of the plurality of groups of the tensile mechanisms are coaxially connected.

[0010] Optionally, the connecting component further comprises an assembly shell, and both sides of the assembly shell are provided with an assembly sleeve and an assembly column extending in different directions respectively, the central axis of the assembly column and the central axis of the assembly sleeve are coaxially arranged, and the connecting shaft comprises the assembly column and the assembly sleeve; the assembly column on one group of the connecting components can be connected to the assembly sleeve on another of the connecting components.

[0011] Optionally, a plurality of connecting tubes are evenly spaced apart in the circumferential direction of the assembly shell, the connecting tubes are extended in the radial direction of the assembly shell, and each of the connecting tubes is connected to one of the driving members.

[0012] According to the hoop tensile testing device of one embodiment of the present invention, the stress loading member includes a force applying plate, the force applying plate is connected to the output end of the driving member, and a side of the force applying plate away from the driving member forms a force applying surface.

[0013] Optionally, the force-applying surface is a curved surface, and the force-applying surface fits the surface of the test piece.

[0014] Optionally, the stress loading member further includes: a movable shaft, one end of which is detachably connected to the output end of the driving member, and the other end of which is connected to the force applying plate.

[0015] Optionally, the stress loading member further includes: a first reinforcement member, a plurality of the first reinforcement members are connected to the movable shaft, the plurality of the first reinforcement members are arranged at an angle to the movable shaft, and the plurality of the first reinforcement members are supported at different positions of the force application plate.

[0016] According to the hoop tensile testing device of one embodiment of the present invention, the driving member includes a pneumatic cylinder, an electric push rod, a hydraulic cylinder or an oil cylinder.

[0017] According to the circumferential tensile testing device of one embodiment of the present invention, the circumferential tensile testing device further comprises an electric control system, wherein the electric control system is connected to the driving member, and the electric control system is used to control the driving member to drive the stress loading member to apply stress.

[0018] A tensile testing method for a pipe body according to an embodiment of the present invention comprises the following steps: supporting a circumferential tensile testing device in the pipe body; controlling each driving member of a plurality of tensile mechanisms to drive a stress loading member to move toward the pipe wall of the pipe body and apply stress; increasing the applied stress to a set value, and determining whether the stresses applied by each of the stress loading members are consistent; if yes, the pipe body is qualified; if not, stopping applying stress and recording data.

[0019] According to the tensile testing method for a pipe body of an embodiment of the present invention, the pipe body is first assembled on a circumferential tensile testing device before testing the pipe body. During the testing of the pipe body, each driving member in the multiple tensile mechanisms drives the stress loading member connected thereto to move toward the pipe wall and apply stress to the pipe wall. If the stress is applied to the set value and the stress applied by each driving member is consistent, the tested pipe body is judged to be qualified. If the stress is applied to the set value but the stress applied by each stress loading member is inconsistent, the driving member controls the stress loading member to stop moving, so as to stop applying stress to the pipe body and record data to determine the performance parameters of the pipe body. The tensile testing method for a pipe body of the present application is simple and easy to operate and the test results are reliable.

[0020] Additional aspects and advantages of the invention will become apparent from the following description, or may be learned by practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0022] Figure 1 This is an exploded view of the fixing seat and the stretching mechanism according to an embodiment of the present invention.

[0023] Figure 2 It is a schematic structural diagram of a circumferential tensile testing device according to an embodiment of the present invention being supported in a test piece.

[0024] Figure 3 The figure is a schematic structural diagram of a driving member according to an embodiment of the present invention.

[0025] Figure 4 The figure is a schematic structural diagram of a fixing base according to an embodiment of the present invention.

[0026] Figure 5 It is an exploded view between the fixing seat and the stretching mechanism according to another embodiment of the present invention.

[0027] Figure 6 This is a schematic structural diagram of a circumferential tensile testing device according to another embodiment of the present invention being supported in a test piece.

[0028] Figure 7 It is a schematic structural diagram of a connection component according to an embodiment of the present invention.

[0029] Figure 8 This is a schematic structural diagram of a connecting component from another angle according to an embodiment of the present invention.

[0030] Fig. 9 An exploded view of a stretching mechanism according to an embodiment of the present invention.

[0031] Fig.10 FIG. 1 is a schematic structural diagram of a stress loading component according to an embodiment of the present invention.

[0032] Fig.11 FIG. 4 is a schematic structural diagram of a stress loading component according to another embodiment of the present invention.

[0033] Fig.12 The present invention is a flow chart of a method for tensile testing of a pipe according to an embodiment of the present invention.

[0034] Reference numerals:

[0035] 100. Hoop tensile test device;

[0036] 1. Fixed seat;

[0037] 11. connecting plate; 111. connecting hole;

[0038] 12. Connecting column;

[0039] 13. Second reinforcement member;

[0040] 2. Stretching mechanism;

[0041] 21. Connect components;

[0042] 211, connecting shaft; 2111, assembly sleeve; 2112, assembly column;

[0043] 212, assembly shell;

[0044] 213, connecting pipe;

[0045] 22. Stretching components;

[0046] 221. Stress loading parts;

[0047] 2211, force applying plate; 2212, force applying surface; 2213, moving axis;

[0048] 2214, first reinforcement member; 2215, connecting seat;

[0049] 222, driving member; 2221, output end; 2222, connecting end;

[0050] 200. Pieces to be tested. DETAILED DESCRIPTION

[0051] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0052] In the description of the present invention, it is necessary to understand that the orientation or positional relationship indicated by the terms "length", "width", "thickness", "up", "down", "inside", "outside", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0053] The hoop tensile testing device 100 according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0054] According to an embodiment of the present invention, a hoop tensile testing device 100 is provided. Figure 1 and Figure 2 As shown, it includes: a fixing seat 1 and at least one set of stretching mechanisms 2.

[0055] Among them, Figure 1 and Figure 2 As shown, each group of stretching mechanisms 2 includes a connecting component 21 and a stretching component 22. The connecting component 21 is connected to the fixing seat 1. The stretching component 22 includes a plurality of stretching components 22, and the plurality of stretching components 22 are arranged at intervals along the circumference of the connecting component 21. Here, each group of stretching mechanisms 2 includes a plurality of stretching components 22.

[0056] Combination Figure 1 and Figure 2 As shown, the stretching assembly 22 includes a stress loading member 221 and a driving member 222. The stress loading member 221 is suitable for abutting against the test piece 200. The driving member 222 is arranged on the connecting assembly 21. The output end 2221 of the driving member 222 (the specific structure of the output end 2221 can be seen in Figure 3 ) is connected to the stress loading member 221, and the driving member 222 is used to drive the stress loading member 221 to apply stress to the test piece 200.

[0057] It can be seen from the above structure that the circumferential tensile testing device 100 of the embodiment of the present invention is provided with a fixing seat 1 and the connecting component 21 in the stretching mechanism 2 is connected to the fixing seat 1. The fixing seat 1 mainly plays the role of supporting the stretching mechanism 2, so that the position of the stretching mechanism 2 is stable during the test of the test piece 200, thereby improving the accuracy of the test. In the process of using the circumferential tensile testing device 100, the stretching mechanism 2 can be connected to the ground, wall or other supporting surfaces through the fixing seat 1, so that the overall position of the circumferential tensile testing device 100 is stable.

[0058] It should be noted that the connection mentioned here can be a non-detachable connection or a detachable connection. When the fixing seat 1 is connected to the stretching mechanism 2 on the ground, wall or other supporting surface in a detachable manner, after the circumferential tensile test device 100 is used, the fixing seat 1 can be removed from the supporting surface, which is convenient for carrying or moving the circumferential tensile test device 100.

[0059] By setting the connecting component 21, on the one hand, the connecting component 21 provides installation space for multiple stretching components 22, and connects the multiple stretching components 22 in the circumferential direction of the connecting component 21, ensuring that the multiple stretching components 22 can form an integral structure through the connecting component 21, and the connecting component 21 can also play a role in supporting the multiple stretching components 22, so that the relative positions of the multiple stretching components 22 are stable; on the other hand, the multiple stretching components 22 are connected to the fixed seat 1 through the connecting component 21, and the fixed seat 1 supports the stretching components 22, so that the stretching components 22 can operate stably during the working process.

[0060] The driving member 222 is connected to the connecting component 21. Since the connecting component 21 is connected to the fixing seat 1, the above arrangement can ensure the stable position of the driving member 222, and the driving member 222 will not shake during operation, thereby reducing the error generated by the driving member 222 during operation and improving the accuracy of the test.

[0061] One end of the stress loading member 221 abuts against the test piece 200, and the other end of the stress loading member 221 is connected to the output end 2221 of the driving member 222. The driving member 222 can drive the stress loading member 221 to move during operation. When the driving member 222 drives the stress loading member 221 to move toward the test piece 200, the stress loading member 221 can apply stress to the test piece 200 to achieve automated testing of the circumferential tensile performance of the test piece 200.

[0062] The stress loading member 221 is connected to the output end 2221 of the driving member 222. When the size of the test piece 200 is large, the driving member 222 can drive the stress loading member 221 to move toward the test piece 200 to increase the size of the connecting component 21 and match the larger test piece 200. When the size of the test piece 200 is small, the driving member 222 can drive the stress loading member 221 to move away from the test piece 200 to reduce the size of the connecting component 21 and match the smaller test piece 200, thereby improving the application range of the circumferential tensile testing device 100.

[0063] It should be noted that the size mentioned here refers to the distance between the test piece 200 and the inner wall. When the test piece 200 is a round tube, the size mentioned here refers to the diameter of the round tube; when the test piece 200 is a square tube or other irregular tube, the size mentioned here refers to the width of the square tube or other irregular tube.

[0064] It can be understood that, compared with the prior art, the circumferential tensile testing device 100 of the present application can automatically perform circumferential tensile performance tests on test pieces 200 of different sizes, and there is no need to cut or perform hole opening processing on the test pieces 200 during the test. The circumferential tensile testing device 100 of the present application has a wide range of applications, high test stability and reliable test results.

[0065] Optionally, the test piece 200 is a hollow tube, which facilitates the circumferential tensile test device 100 to be mounted inside the tube and apply stress to the tube. In other words, the circumferential tensile test device 100 of the present application is mainly used to test the circumferential tensile performance of the tube, especially to test the circumferential tensile performance of the round tube to evaluate the performance of the round tube.

[0066] Alternatively, if Figure 4 As shown, the fixing seat 1 includes a connecting plate 11 and a connecting column 12, one end of the connecting column 12 is connected to one side of the connecting plate 11, and the other end of the connecting column 12 is suitable for connecting to the connecting component 21. The connecting component 21 can be connected to the fixing seat 1, and the connecting plate 11 is mainly used to increase the contact area between the fixing seat 1 and the supporting surface. By connecting the fixing seat 1 to the supporting surface, the connection strength between the fixing seat 1 and the supporting surface can be increased.

[0067] Optionally, the connecting column 12 may be made of a steel rod with a sufficient radius and length, so that the connecting column 12 itself has sufficient rigidity and strength to ensure the stability of the circumferential tensile testing device 100 during the test.

[0068] Alternatively, if Figure 4As shown, the fixing base 1 further includes a second reinforcement member 13, a plurality of second reinforcement members 13 are connected to the connecting column 12, the plurality of second reinforcement members 13 are arranged at an angle to the connecting column 12, and the plurality of second reinforcement members 13 are supported at different positions of the connecting plate 11. The second reinforcement member 13 is used to strengthen the structural strength of the fixing base 1, and ensure that the position of the stretching mechanism 2 is stable when the stretching mechanism 2 is connected to the fixing base 1.

[0069] In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0070] Optionally, the connecting column 12 and the second reinforcement 13 are both connected to the connecting plate 11 by welding, and the end of the second reinforcement 13 away from the connecting plate 11 is connected to the connecting column 12 by welding. The connection strength between the components of the fixing base 1 is increased, so that the fixing base 1 is stable after assembly.

[0071] Of course, in some other examples, the fixing seat 1 can also be made by an integrated molding process. The integrated molding process can ensure that the fixing seat 1 does not need to be machined by welding, polishing, grinding, etc. in the early stage of the connecting plate 11, the connecting column 12, and the second reinforcement member 13 during the assembly process, which effectively simplifies the assembly process and improves the production efficiency of the fixing seat 1.

[0072] Optionally, the connecting plate 11 is a steel plate with sufficient length, width and thickness, so that the connecting plate 11 itself has sufficient rigidity and strength to ensure that the circumferential tensile testing device 100 can be stably fixed on the supporting surface.

[0073] Alternatively, if Figure 4 As shown, a plurality of connection holes 111 are provided on the connection plate 11. The connection holes 111 are used to avoid the connection piece connecting the hoop tensile test device 100 to the support surface, so that the hoop tensile test device 100 can be stably fixed on the support surface, thereby improving the position stability of the hoop tensile test device 100.

[0074] Optionally, the connection assembly 21 is detachably connected to the fixing seat 1. By adopting a detachable connection, on the one hand, the circumferential tensile test device 100 of the present application can be formed into an assembled circumferential tensile test device 100. When the circumferential tensile test device 100 is not in use, the stretching mechanism 2 can be removed from the fixing seat 1 through the connection assembly 21, thereby reducing the occupied space of the circumferential tensile test device 100 and facilitating transportation and storage; on the other hand, when one of the stretching mechanism 2 or the fixing seat 1 is damaged or worn, only one of the damaged components needs to be replaced through the detachable connection, thereby reducing the use cost of the circumferential tensile test device 100.

[0075] Optionally, the driving member 222 and the connecting assembly 21 may be connected in a detachable manner. The beneficial effects of the detachable connection here can be referred to the beneficial effects of detachably connecting the connecting assembly 21 to the fixing seat 1, which will not be described in detail here.

[0076] Of course, in some other examples, the connection method is not limited to the above-mentioned detachable connection, and technicians can also make a choice based on actual engineering requirements, and no specific restrictions are made here.

[0077] Optionally, the output end 2221 of the driving member 222 can be detachably connected to the stress loading member 221 . On the one hand, the circumferential tensile test device 100 of the present application can be formed into an assembled circumferential tensile test device 100. When the circumferential tensile test device 100 is not in use, the stress loading member 221 can be removed from the fixing seat 1, thereby reducing the space occupied by the circumferential tensile test device 100 and facilitating transportation and storage. On the other hand, the present application can be provided with a plurality of stress loading members 221 of different sizes, and stress loading members 221 of different sizes can test test pieces 200 of different sizes. Therefore, the output end 2221 of the driving member 222 and the stress loading member 221 are provided with a detachable connection to facilitate replacement of the stress loading member 221. By replacing the size of the stress loading member 221, it is possible to test test pieces 200 of different sizes, thereby further improving the scope of application of the circumferential tensile test device 100. On the third hand, when one of the driving member 222 or the stress loading member 221 is damaged or worn, only one of the damaged components needs to be replaced through the detachable connection, thereby reducing the use cost of the circumferential tensile test device 100.

[0078] In a specific example, Figure 3 As shown, output ends 2221 and connection ends 2222 are provided on both sides of the driving member 222 . The output end 2221 is used to connect to the stress loading member 221 , and the connection end 2222 is used to connect the driving member 222 to the connection assembly 21 .

[0079] Specifically, the output end 2221 is provided with a first external thread, and the connection end 2222 is provided with a second external thread. Accordingly, the stress loading member 221 connected to the output end 2221 is provided with a first internal thread matched with the first external thread, and the connection assembly 21 connected to the connection end 2222 is provided with a second internal thread matched with the second external thread. By connecting the first internal thread to the first external thread, the stress loading member 221 is detachably connected to the output end 2221, and by connecting the second internal thread to the second external thread, the connection assembly 21 is detachably connected to the connection end 2222.

[0080] In some other examples, the detachable connection is not limited to the above-mentioned threaded connection, and other connection methods that can achieve detachable connection can also be selected, which is not specifically limited here.

[0081] In some embodiments of the present invention, Figure 5 and Figure 6 As shown, the connection assembly 21 includes a connection shaft 211, and the stretching mechanism 2 includes multiple groups, and the connection shafts 211 of the multiple groups of stretching mechanisms 2 are coaxially connected. The connection shaft 211 mainly plays a connecting role, and the multiple groups of stretching mechanisms 2 are connected in series along the axial direction of the connection shaft 211 to form an integrated structure, thereby increasing the axial height of the hoop tensile test device 100, so that the hoop tensile test device 100 of the present application can perform hoop tensile performance tests on the test pieces 200 of different lengths, wherein, Figure 6 The schematic diagram shows two sets of stretching mechanisms 2 connected in series to perform a circumferential tensile performance test on a long test piece 200 .

[0082] It should be noted that the stress loading member 221 of the present application is detachably connected to the output end 2221 of the driving member 222. When the circumferential tensile testing device 100 includes multiple groups of tensile mechanisms 2, and the multiple groups of tensile mechanisms 2 are connected in series along the axial direction of the connecting shaft 211, the size of the stress loading member 221 on each group of tensile mechanisms 2 can be selectively set.

[0083] For example, when the sizes of two adjacent locations on the same test piece 200 are different, the circumferential tensile testing device 100 of the present application can be used to coaxially connect the connecting shafts 211 of at least two groups of tensile mechanisms 2, and the stress loading members 221 on the two groups of tensile mechanisms 2 have different sizes to match the sizes of different locations on the same test piece 200, thereby improving the applicability of the circumferential tensile testing device 100.

[0084] Optionally, the connecting shaft 211 can be made of a steel rod with a sufficient radius and length, so that the connecting shaft 211 itself has sufficient rigidity and strength. When multiple groups of stretching mechanisms 2 are connected in series through the connecting shaft 211, the steel connecting shaft 211 can ensure the position stability between the multiple groups of stretching mechanisms 2, further improving the structural stability of the circumferential tensile testing device 100.

[0085] Optionally, combined Figure 7 and Figure 8 As shown, the connection assembly 21 also includes an assembly shell 212. The assembly shell 212 is mainly used to increase the area of ​​the connection assembly 21, because after the subsequent circumferential tensile test device 100 is processed and formed, multiple connection tubes 213 need to be arranged in the circumferential direction of the assembly shell 212. The connection assembly 21 with a larger area can ensure that multiple connection tubes 213 can be connected to the assembly shell 212, and the multiple connection tubes 213 are independent of each other.

[0086] Optionally, both sides of the assembly shell 212 are respectively provided with an assembly sleeve 2111 and an assembly column 2112 extending in different directions, and the central axis of the assembly column 2112 is coaxially arranged with the central axis of the assembly sleeve 2111. The assembly sleeve 2111 and the assembly column 2112 are mainly used to connect multiple sets of stretching mechanisms 2. The coaxial arrangement of the central axis of the assembly column 2112 and the central axis of the assembly sleeve 2111 can ensure that after the multiple sets of stretching mechanisms 2 are connected together, the connecting shafts 211 of the multiple sets of stretching mechanisms 2 can be coaxially connected.

[0087] Optionally, the assembly sleeve 2111 and the assembly column 2112 can be welded on both sides of the assembly shell 212 to improve the connection strength between the assembly sleeve 2111, the assembly column 2112 and the assembly shell 212. In other examples, CNC machining technology can also be used for integrated processing and forming, and the specific connection method is not limited here, and the technician can select the connection method according to actual needs.

[0088] Optionally, the connecting shaft 211 includes an assembly column 2112 and an assembly sleeve 2111; the assembly column 2112 on one set of connecting components 21 can be connected to the assembly sleeve 2111 on another connecting component 21. This realizes the coaxial connection of the connecting shafts 211 of multiple sets of stretching mechanisms 2, increases the axial height of the hoop tensile testing device 100, enables the hoop tensile testing device 100 of the present application to perform hoop tensile performance tests on test pieces 200 of different lengths, and improves the scope of application of the hoop tensile testing device 100.

[0089] In a specific example, Figure 8 As shown, the outer side of the assembly column 2112 is provided with a third external thread, and the assembly sleeve 2111 is formed into a hollow structure and provided with a third internal thread inside, wherein the third external thread on one set of connection components 21 can be matched and connected with the third internal thread on another connection component 21 to form a detachable connection. When the length of the test piece 200 to be tested is short, part of the stretching mechanism 2 can be removed from the circumferential tensile test device 100; when the length of the test piece 200 to be tested is long, multiple stretching mechanisms 2 can be connected to the circumferential tensile test device 100 through the third external thread and the third internal thread, so as to test the test pieces 200 of different lengths.

[0090] Optionally, a fourth external thread is provided at one end of the connecting column 12 away from the connecting plate 11, and the fourth external thread is used to cooperate with a third internal thread provided in the assembly sleeve 2111 on one set of connecting components 21, so as to realize the detachable connection of the connecting component 21 to the fixing seat 1.

[0091] In the description of the present invention, features limited to "first", "second", "third" and "fourth" may explicitly or implicitly include one or more of the features, and are used to distinguish and describe the features, without any order or importance.

[0092] Alternatively, if Fig. 9 As shown, the assembly shell 212 is evenly spaced in the circumferential direction and provided with a plurality of connecting tubes 213, the connecting tubes 213 are extended in the radial direction of the assembly shell 212, and each connecting tube 213 is connected to a driving member 222. That is to say, each connecting assembly 21 is provided with a plurality of driving members 222, and since the output end 2221 of each driving member 222 is connected with a stress loading member 221, the plurality of stress loading members 221 are evenly spaced in the circumferential direction of the assembly shell 212 and are extended in the radial direction of the assembly shell 212. When the tensile performance of the test piece 200 needs to be tested, the plurality of stress loading members 221 can simultaneously generate displacement and apply stress to the test piece 200, so as to test the circumferential tensile performance of the test piece 200.

[0093] It should be noted that the above-mentioned multiple connecting tubes 213 are evenly spaced along the circumference of the assembly shell 212, which means that the intervals between two adjacent connecting tubes 213 connected to the assembly shell 212 are equal.

[0094] For example, the outer surface of the assembly shell 212 is formed as a circular surface. When four connecting tubes 213 are axially arranged in the assembly shell 212, the angle between the four connecting tubes 213 should be 90°; when six connecting tubes 213 are axially arranged in the assembly shell 212, the angle between the six connecting tubes 213 should be 60°.

[0095] Optionally, a second internal thread that cooperates with the second external thread is opened inside the connecting tube 213, and the connecting end 2222 of the driving member 222 is connected to the connecting tube 213 through the second external thread and the second internal thread, thereby realizing a detachable connection between the connecting component 21 and the connecting end 2222.

[0096] Optionally, the assembly shell 212 can use a steel disc with a sufficient radius and height, so that the assembly shell 212 itself has sufficient rigidity and strength. When multiple connecting tubes 213 are connected to the circumference of the assembly shell 212, the assembly shell 212 can support the connecting tubes 213, so that the position of the tensile component 22 connected to the connecting tubes 213 is stable.

[0097] In some embodiments of the present invention, Fig. 9As shown, the stress loading member 221 includes a force applying plate 2211, which is connected to the output end 2221 of the driving member 222, and a side of the force applying plate 2211 away from the driving member 222 forms a force applying surface 2212. The force applying plate 2211 is used to fit with the inner surface of the test piece 200 to increase the contact area between the hoop tensile testing device 100 and the test piece 200. When the driving member 222 drives the stress loading member 221 to apply stress to the test piece 200, the force applying plate 2211 can convert the linear load delivered by the driving member 222 into a surface load.

[0098] Optionally, the driving member 222 has a sufficient stroke and can generate a sufficient lifting load for testing the hoop tensile performance of the test piece 200 .

[0099] Optionally, the force-applying surface 2212 is a curved surface, and the force-applying surface 2212 is in contact with the surface of the test piece 200. When the hoop tensile testing device 100 tests the hoop tensile performance of the test piece 200, the force-applying surface 2212 can always abut against the surface of the test piece 200 and apply stress to the test piece 200. Subsequently, the tensile performance of the test piece 200 can be tested by monitoring the stress value between the force-applying surface 2212 and the test piece 200.

[0100] Optionally, combined Fig. 9 and Fig.10 As shown, the stress loading member 221 further includes a moving shaft 2213, one end of which is detachably connected to the output end 2221 of the driving member 222, and the other end of which is connected to the force applying plate 2211. The force applying plate 2211 is connected to the output end 2221 of the driving member 222 via the moving shaft 2213. During operation, the driving member 222 can drive the moving shaft 2213 to move, thereby driving the force applying plate 2211 connected to the moving shaft 2213 to move, so that the force applying plate 2211 can apply stress to the test piece 200, thereby testing the tensile performance of the test piece 200.

[0101] Optionally, the movable shaft 2213 may be a steel rod with an inner threaded hole, and the size of the threaded hole on the movable shaft 2213 matches the size of the first outer thread on the output end 2221. In order to achieve a detachable connection between the movable shaft 2213 and the output end 2221 of the driving member 222, and the movable shaft 2213 is set as a steel rod, in a specific example, the movable shaft 2213 may be a steel rod with a sufficient radius and length, so that the movable shaft 2213 itself has sufficient rigidity and strength, so that the force plate 2211 can be stably connected to the output end 2221 of the driving member 222, and the driving member 222 can drive the force plate 2211 to move stably during operation.

[0102] Alternatively, if Fig.10As shown, the stress loading member 221 also includes a first reinforcement member 2214, and a plurality of first reinforcement members 2214 are connected to the moving shaft 2213. The plurality of first reinforcement members 2214 are arranged at an angle to the moving shaft 2213, and the plurality of first reinforcement members 2214 are supported at different positions of the force applying plate 2211. The second reinforcement member 13 is used to strengthen the structural strength of the stress loading member 221 on the one hand. When the driving member 222 drives the stress loading member 221 to apply stress to the test piece 200, the position of the stress loading member 221 is stable, thereby improving the accuracy of the test of the hoop tensile test device 100; on the other hand, the plurality of first reinforcement members 2214 can convert the jacking load transmitted by the driving member 222 into a multi-directional load and transmit it to the force applying plate 2211. The force applying plate 2211 then converts the multi-directional load transmitted by the plurality of first reinforcement members 2214 into a surface load, thereby improving the accuracy of the test.

[0103] Optionally, the movable shaft 2213 and the first reinforcement member 2214 are both connected to the force plate 2211 by welding, and one end of the first reinforcement member 2214 away from the force plate 2211 is connected to the movable shaft 2213 by welding. The connection strength between the components of the stress loading member 221 is increased, so that the position of the stress loading member 221 is stable after assembly.

[0104] Of course, in some other examples, the stress loading member 221 may also be made by an integrated molding process. The integrated molding process can ensure that the stress loading member 221 does not need to be machined by welding, polishing, grinding, etc. in the early stage of the force plate 2211, the movable shaft 2213, and the first reinforcement member 2214 during the assembly process, which effectively simplifies the assembly process and improves the production efficiency of the stress loading member 221.

[0105] Alternatively, if Fig.10 As shown, the stress loading member 221 further includes a connection seat 2215. The connection seat 2215 mainly provides an installation space for the arrangement of multiple first reinforcement members 2214, so that the multiple first reinforcement members 2214 are connected to the stress loading member 221 in a stable position, further improving the structural stability of the stress loading member 221, and the multiple first reinforcement members 2214 can effectively play the role of strengthening the structure and transmitting force.

[0106] In a specific example, by adopting the above structure, the circumferential tensile test device 100 of the present application is first fixed to the support surface by bolts before being used, and then the assembly shell 212 is fixed to the fixed base 1 by threaded docking. After the assembly shell 212 is installed, due to the multiple connecting tubes 213 around the assembly shell 212, the connecting end 2222 of the driving member 222 is fixed to the assembly shell 212 by threaded docking, and the output end 2221 of the driving member 222 extends in a direction away from the assembly shell 212. Before assembling the stress loading member 221, first determine The size of the test piece 200 is determined, and the size of the stress loading member 221 is determined according to the size of the test piece 200. The stress loading member 221 suitable for the test piece 200 is fixed to the output end 2221 of the driving member 222 by threaded docking. At this time, one layer of the stretching mechanism 2 and the fixing seat 1 are installed. When the length of the test piece 200 is longer, another stretching mechanism 2 can be installed at one end of the installed stretching mechanism 2. The two adjacent stretching mechanisms 2 are threadedly connected by the assembly sleeve 2111 and the assembly column 2112 to realize testing of test pieces 200 of different sizes.

[0107] in, Fig.10 and Fig.11 The stress loading members 221 of different sizes are shown respectively. When the diameter or width of the test piece 200 is small, the stress loading member 221 of different sizes can be used. Fig.10 When the diameter or width of the test piece 200 is large, the stress loading member 221 can be used. Fig.11 The stress loading member 221 is mainly used to ensure that the hoop tensile test device 100 can be supported in the pipe body, thereby increasing the application scope of the hoop tensile test device 100.

[0108] Of course, the size of the stress loading member 221 is not limited to Fig.10 and Fig.11 The stress loading member 221 shown is a stress loading member 221 of various specifications that can be designed by a technician according to the size of the test piece 200 , which are not shown one by one herein.

[0109] In some embodiments of the present invention, the driving member 222 includes a cylinder, an electric push rod, a hydraulic cylinder or an oil cylinder. The above structures can ensure that the driving member 222 has a sufficient stroke and can generate a sufficient lifting load. During the operation of the circumferential tensile testing device 100, the stress loading member 221 can be stably driven to apply stress to the test piece 200, and the displacement of the output end 2221 of the above structure can be accurately controlled, thereby improving the reliability and accuracy of the test and realizing the automated test of the tensile performance of the test piece 200.

[0110] In some embodiments of the present invention, the hoop tensile testing device 100 further includes an electric control system, which is connected to the driving member 222 and is used to control the driving member 222 to drive the stress loading member 221 to apply stress. Automatic control of the displacement of the output end 2221 of the driving member 222 is achieved, and the use of the electric control system to control the driving member 222 can ensure accurate control and improve the accuracy of the test.

[0111] Optionally, an electronic control system can simultaneously control multiple driving members 222 to drive stress loading members 221 to apply stress. During the operation of the electronic control system, the electronic control system can ensure that the displacements output by the multiple driving members 222 are equal, that is, when the multiple driving members 222 drive the multiple stress loading members 221 to apply stress toward the test piece 200, the stress values ​​exerted by the multiple stress loading members 221 on the test piece 200 are consistent, so as to achieve uniform force control and improve the accuracy of the test.

[0112] The tensile testing method according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0113] A tensile testing method for a pipe according to an embodiment of the present invention is as follows: Fig.12 As shown, the following steps are included:

[0114] Step S1, installing the hoop tensile testing device 100 in the pipe body.

[0115] Step S2, controlling the driving members 222 of the plurality of stretching mechanisms 2 to drive the stress applying member 221 to move toward the tube wall of the tube body and apply stress.

[0116] Step S3, increase the applied stress to the set value, and determine whether the stresses applied by the stress loading components 221 are consistent; if yes, the pipe body is qualified; if no, stop applying stress and record data.

[0117] It can be known from the above method that the tensile test method of the pipe body of the embodiment of the present invention is to support the circumferential tensile test device 100 in the pipe body. When the pipe body needs to be subjected to a reversing tensile test, the electronic control system controls each driving member 222 to drive the stress loading member 221 to move toward the pipe wall of the pipe body and apply stress. If the stress is applied to the set value and the stress applied by each driving member 222 is consistent, the tested pipe body is judged to be qualified. If the stress is applied to the set value but the stress applied by each stress loading member 221 is inconsistent, the driving member 222 controls the stress loading member 221 to stop moving, so as to stop applying stress to the pipe body and record data to determine the performance parameters of the pipe body. The tensile test method of the pipe body of the present application is simple and easy to operate and the test results are reliable.

[0118] It should be noted that in the steps of the above-mentioned tube tensile test method, the circumferential tensile test device 100 is the aforementioned circumferential tensile test device 100, and the specific structure of the circumferential tensile test device 100 is not repeated, and the tube is the aforementioned test piece 200.

[0119] Optionally, in order to accurately determine the stress applied to the pipe body by each stress loading component 221, a stress sensor may be provided on each stress loading component 221. The stress sensor is used to monitor the stress generated between the stress loading component 221 and the pipe body, so that the circumferential tensile testing device 100 can intuitively determine whether the stress applied by each stress loading component 221 is consistent. When one of the stress loading components 221 applies stress to the pipe body causing damage, the value of the stress sensor on the stress loading component 221 will decrease or drop to zero, thereby determining that the pipe body is damaged, and further determining the circumferential tensile material performance parameters of the pipe body.

[0120] In other examples, the electric control system itself has a device for monitoring stress values, and the stress values ​​generated between each stress loading member 221 and the pipe body can be automatically monitored by the electric control system, thereby determining the circumferential tensile material performance parameters of the pipe body.

[0121] In a specific example, the hoop tensile material performance parameters of the pipe body can be determined by observing the displacement of the output end 2221 of the driving member 222. Specifically, the driving member 222 drives the stress loading member 221 to move toward the pipe body and generate a relative displacement. When the displacements of the stress loading members 221 are consistent, but the stress values ​​between the stress loading members 221 and the pipe body are inconsistent or the stress value between at least one of the stress loading members 221 and the pipe body is zero, it is determined that the pipe body is damaged, and then the hoop tensile material performance parameters of the pipe body are determined.

[0122] The specific structure of the hoop tensile testing device 100 in a specific embodiment of the present invention is described below in conjunction with the accompanying drawings. The embodiments of the present invention may be all embodiments after combining the aforementioned multiple technical solutions, but are not limited to the following specific embodiments, which all fall within the protection scope of the present invention.

[0123] Example 1

[0124] A hoop tensile testing device 100, such as Figure 1 and Figure 2 As shown, it includes: a fixing seat 1 and at least one set of stretching mechanisms 2.

[0125] Among them, Figure 1 and Figure 2 As shown, each group of stretching mechanisms 2 includes a connecting component 21 and a stretching component 22 . The connecting component 21 is connected to the fixing seat 1 . The stretching component 22 includes a plurality of stretching components 22 . The plurality of stretching components 22 are arranged at intervals along the circumference of the connecting component 21 .

[0126] Combination Figure 1 and Figure 2 As shown, the stretching assembly 22 includes a stress loading member 221 and a driving member 222. The stress loading member 221 is suitable for abutting against the test piece 200. The driving member 222 is arranged on the connecting assembly 21. The output end 2221 of the driving member 222 (the specific structure of the output end 2221 can be seen in Figure 3 ) is connected to the stress loading member 221, and the driving member 222 is used to drive the stress loading member 221 to apply stress to the test piece 200.

[0127] Example 2

[0128] A hoop tensile testing device 100, based on Example 1, as Figure 1 As shown, it includes: a fixing seat 1, a stretching mechanism 2 and an electric control system (not shown in the figure).

[0129] like Figure 4 As shown, the fixing base 1 includes a connecting plate 11, a connecting column 12 and four second reinforcement members 13, one end of the connecting column 12 is connected to a side surface of the connecting plate 11, the other end of the connecting column 12 is connected to the connecting assembly 21, the four second reinforcement members 13 are arranged at an angle to the connecting column 12, and the four second reinforcement members 13 are supported at different positions of the connecting plate 11.

[0130] like Figure 8 As shown, the connecting assembly 21 includes a connecting shaft 211 and an assembly shell 212. The two sides of the assembly shell 212 are respectively provided with an assembly sleeve 2111 and an assembly column 2112 extending in different directions. The central axis of the assembly column 2112 is coaxially arranged with the central axis of the assembly sleeve 2111.

[0131] like Fig. 9 As shown, a plurality of connecting tubes 213 are evenly spaced around the circumference of the assembly shell 212 . The connecting tubes 213 are extended along the radial direction of the assembly shell 212 , and each connecting tube 213 is connected to a driving member 222 .

[0132] The tensile assembly 22 includes a stress loading member 221 and a driving member 222. The stress loading member 221 is adapted to abut against the test piece 200. The driving member 222 is disposed on the connecting assembly 21. The output end 2221 of the driving member 222 (the specific structure of the output end 2221 can be seen in Figure 3 ) is connected to the stress loading member 221, and the driving member 222 is used to drive the stress loading member 221 to apply stress to the test piece 200.

[0133] like Fig. 9As shown, the stress loading member 221 includes a force plate 2211, a movable shaft 2213 and two first reinforcement members 2214. The force plate 2211 is connected to the output end 2221 of the driving member 222. A side of the force plate 2211 away from the driving member 222 forms a force surface 2212. One end of the movable shaft 2213 is detachably connected to the output end 2221 of the driving member 222. The other end of the movable shaft 2213 is connected to the force plate 2211. Two first reinforcement members 2214 are connected to the movable shaft 2213. The two first reinforcement members 2214 are arranged at an angle to the movable shaft 2213. The two first reinforcement members 2214 are supported at different positions of the force plate 2211.

[0134] The electric control system is connected to the driving member 222 , and the electric control system is used to control the driving member 222 to drive the stress loading member 221 to apply stress.

[0135] Example 3

[0136] A method for testing the tensile strength of a pipe body, using the circumferential tensile testing device 100 in Example 2 to test the circumferential tensile performance of the pipe body, comprises the following steps:

[0137] Step S1, installing the hoop tensile testing device 100 in the pipe body.

[0138] Step S2, controlling the driving members 222 of the plurality of stretching mechanisms 2 to drive the stress applying member 221 to move toward the tube wall of the tube body and apply stress.

[0139] Step S3, increase the applied stress to the set value, and determine whether the stresses applied by the stress loading components 221 are consistent; if yes, the pipe body is qualified; if no, stop applying stress and record data.

[0140] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation" and "connection" 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 or an electrical connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0141] Figure 5 Two stretching mechanisms 2 are shown for illustrative purposes, but after reading the above technical solution, ordinary technicians can obviously understand that the solution can be applied to a technical solution with three or more stretching mechanisms 2, which also falls within the protection scope of the present invention.

[0142] Other components of the hoop tensile testing device 100 and the tensile testing method according to the embodiment of the present invention, such as the driving principle of the driving member 222 , are well known to those skilled in the art and will not be described in detail here.

[0143] In the description of this specification, the description with reference to the terms "embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0144] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A hoop tensile test device, characterized in that: include: Fixed seat; At least one set of stretching mechanisms, each set of stretching mechanisms comprising: A connecting component, wherein the connecting component is connected to the fixing seat; A stretching assembly, the stretching assembly comprises a plurality of stretching assemblies, and the plurality of stretching assemblies are arranged at intervals along the circumference of the connecting assembly; The stretching assembly comprises: A stress loading member, wherein the stress loading member is adapted to abut against a test piece; A driving member, wherein the driving member is arranged on the connecting assembly, an output end of the driving member is connected to the stress loading member, and the driving member is used to drive the stress loading member to apply stress to the test piece.

2. The hoop tensile test device according to claim 1, characterized in that: The connecting assembly includes a connecting shaft, and the stretching mechanism includes multiple groups, and the connecting shafts of the multiple groups of stretching mechanisms are coaxially connected.

3. The hoop tensile test device according to claim 2, characterized in that: The connection component also includes an assembly shell, and assembly sleeves and assembly columns are respectively extended in different directions on both sides of the assembly shell, the central axis of the assembly column and the central axis of the assembly sleeve are coaxially arranged, and the connecting shaft includes the assembly column and the assembly sleeve; the assembly columns on one group of the connection components can be connected to the assembly sleeve on another connection component.

4. The hoop tensile test device according to claim 3, characterized in that: A plurality of connecting tubes are evenly spaced around the circumference of the assembly shell. The connecting tubes are extended along the radial direction of the assembly shell, and each of the connecting tubes is connected to one of the driving members.

5. The hoop tensile test device according to any one of claims 1 to 3, characterized in that: The stress loading member comprises a force applying plate, the force applying plate is connected to the output end of the driving member, and a side surface of the force applying plate away from the driving member forms a force applying surface.

6. The hoop tensile test device according to claim 5, characterized in that: The force-applying surface is a curved surface, and the force-applying surface is in contact with the surface of the to-be-tested piece.

7. The hoop tensile test device according to claim 5, characterized in that: The stress loading member further comprises: A movable shaft, one end of which is detachably connected to the output end of the driving member, and the other end of which is connected to the force application plate.

8. The hoop tensile test device according to claim 7, characterized in that: The stress loading member further comprises: A first reinforcement member, wherein a plurality of the first reinforcement members are connected to the movable shaft, the plurality of the first reinforcement members are arranged at an angle to the movable shaft, and the plurality of the first reinforcement members are supported at different positions of the force application plate.

9. The hoop tensile test device according to any one of claims 1 to 3, characterized in that: The driving member includes an air cylinder, an electric push rod, a hydraulic cylinder or an oil cylinder.

10. The hoop tensile test device according to any one of claims 1 to 3, characterized in that: It also includes an electric control system, which is connected to the driving member and is used to control the driving member to drive the stress loading member to apply stress.

11. A method for tensile testing of a pipe body, characterized in that: The following steps are involved: A circumferential tensile test device is supported in the pipe body, wherein the circumferential tensile test device is the circumferential tensile test device according to any one of claims 1 to 10; Controlling each driving member of the plurality of stretching mechanisms to drive the stress loading member to move toward the tube wall of the tube body and apply stress; Increasing the applied stress to a set value, and determining whether the stresses applied by the stress loading components are consistent; If yes, the pipe body is qualified; if no, stop applying stress and record the data.

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