Multi-point type flexibly-arranged fatigue test device for expansion joint

Abstract

The utility model discloses a multi-point type flexibly-arranged fatigue test device for an expansion joint, and particularly relates to the technical field of metal expansion joint body fatigue test equipment, the multi-point type flexibly-arranged fatigue test device comprises an expansion joint body, and a plurality of reciprocating test assemblies are arranged on the expansion joint body in an array mode. According to the multi-point type flexibly-arranged fatigue test device for the expansion joint, provided by the utility model, the plurality of reciprocating test assemblies are arranged on the expansion joint body in an array manner, and the expansion joint body is controlled to stretch out and draw back through the reciprocating test assemblies, so that a fatigue test is carried out; and different numbers of reciprocating test assemblies can be arranged to adapt to expansion joints with different calibers, so that the application range of the device is expanded.

Description

Technical Field

[0001] The utility model relates to the technical field of fatigue testing equipment for metal expansion joints, in particular to a multi-point fatigue testing device for expansion joints that can be flexibly arranged. Background Art

[0002] As is well known, fatigue testing involves simulating the cyclic loads experienced in actual use to assess the durability and stability of metal expansion joints over long-term use. Because the fatigue characteristics of metal expansion joints involve changes in their microstructure, the fatigue behavior of expansion joints becomes complex under load, which in turn affects their mechanical properties. Furthermore, the design and material selection of metal expansion joints also directly affect their fatigue performance. Therefore, fatigue testing of metal expansion joints is essential.

[0003] For example, the Chinese patent document entitled "High-Pressure Metal Bellows Tensile Fatigue Test Device," with authorization announcement number CN209280497U and announcement date August 20, 2019, comprises a lower base, an upper fixed plate, a tensioning cylinder, and an air supply assembly. The upper end of the lower base is connected to the upper fixed plate via multiple guide rods, which are slidably connected to the multiple guide rods via guide sleeves. The lower base is provided with a slide groove, in which a lower flange slides, and the upper end of the lower flange is connected to the upper flange via multiple connecting rods. The upper and lower ends of the metal bellows used for testing are welded to the upper and lower flanges, respectively. An anti-twist shield is provided between the upper and lower flanges and is mounted on the outer ring of the metal bellows. This patented structure is simple, compact, and rational, capable of completing tensile fatigue tests on large-diameter metal bellows under high-pressure conditions, and operates stably and reliably.

[0004] A drawback of existing technology is that, when fatigue testing a metal expansion joint, the joint is placed on a base and driven to reciprocate and extend by an existing linear reciprocating drive. Because the equipment is designed for expansion joints of a fixed size, it cannot accommodate expansion joints of various sizes. Utility Model Content

[0005] The purpose of the utility model is to provide a multi-point fatigue test device for expansion joints that can be flexibly arranged to solve the above-mentioned deficiencies in the prior art.

[0006] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0007] A multi-point fatigue test device for an expansion joint with flexible arrangement comprises an expansion joint body on which a plurality of reciprocating test assemblies are arranged in an array.

[0008] The above-mentioned fatigue test device for expansion joints is multi-point and can be flexibly arranged, and the reciprocating test component is an oil cylinder.

[0009] The above-mentioned multi-point, flexibly arranged fatigue testing device for expansion joints has an upper supporting tube and a lower supporting tube fixedly connected at both ends of the expansion joint body, an upper connecting piece is provided on the upper supporting tube, and a lower connecting piece is provided on the lower supporting tube, and the oil cylinder is located between the upper connecting piece and the lower connecting piece.

[0010] The above-mentioned multi-point fatigue testing device for expansion joints that can be flexibly arranged, the upper connecting member and the lower connecting member are both L-shaped.

[0011] The above-mentioned multi-point fatigue testing device for expansion joints can be flexibly arranged, and the output end of the oil cylinder is provided with a pressure sensor.

[0012] The above-mentioned multi-point fatigue testing device for expansion joints can be flexibly arranged, and a positioning sleeve is fixedly connected to the output end of the oil cylinder.

[0013] The above-mentioned multi-point fatigue testing device for expansion joints that can be flexibly arranged has a displacement sensor provided between the positioning sleeve and the lower connecting piece.

[0014] The above-mentioned multi-point fatigue testing device for expansion joints that can be flexibly arranged has an adjustable limiting mechanism provided between the upper connecting member and the lower connecting member.

[0015] The above-mentioned multi-point, flexibly arranged fatigue testing device for expansion joints, the adjustable limiting mechanism includes a sliding rod fixedly connected to the lower connecting member, the upper connecting member is slidably connected to the sliding rod, and a limiting member is provided on the sliding rod, and the limiting member is located on the movement stroke of the upper connecting member.

[0016] In the above-mentioned multi-point fatigue testing device for expansion joints that can be flexibly arranged, the distance between the upper connecting member and the limiting member is 10 mm.

[0017] In the above technical solution, the utility model provides a multi-point, flexibly arranged fatigue test device for expansion joints, which is arranged by setting a plurality of reciprocating test assemblies, and the plurality of reciprocating test assemblies are arranged in an array on the expansion joint body. The expansion joint body is controlled to extend and retract by the reciprocating test assemblies to perform fatigue tests, and different numbers of reciprocating test assemblies can be set to adapt to expansion joints of different calibers, thereby improving the scope of application of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0019] Figure 1 A schematic diagram of the overall structure provided for an embodiment of the present utility model;

[0020] Figure 2 A schematic cross-sectional view of a reciprocating test assembly provided in an embodiment of the present invention;

[0021] Figure 3 A schematic cross-sectional view of the reciprocating test assembly provided by an embodiment of the present invention from another perspective;

[0022] Figure 4 for Figure 3 A magnified schematic diagram of the local structure at center A;

[0023] Figure 5 This is a partial cross-sectional structural schematic diagram provided for another embodiment of the present invention.

[0024] Description of reference numerals:

[0025] 1. Expansion joint body; 2. Oil cylinder; 3. Cylinder barrel; 4. Piston rod; 5. Upper support pipe; 6. Lower support pipe; 7. Upper connecting piece; 8. Lower connecting piece; 9. Screw; 10. Positioning sleeve; 11. Pressure sensor; 12. Displacement sensor; 13. Slide rod; 14. Upper limit piece; 15. Lower limit piece; 16. Oil storage chamber; 17. Oil outlet hole; 18. Steel ball. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0027] In the description of this utility model, it is necessary to understand that Figure 3 The position of the upper middle connecting member relative to the lower connecting member is upper, and vice versa. The terms "center", "longitudinal", "lateral", "length", "width", "degree", "up", "down", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, they should not be understood as limiting the present invention.

[0028] Reference Figure 1-5 The embodiment of the present invention provides a multi-point fatigue test device for an expansion joint that can be flexibly arranged, including an expansion joint body 1, on which a plurality of reciprocating test assemblies are arranged in an array.

[0029] Specifically, when the expansion joint body 1 is subjected to a fatigue test, the expansion joint body 1 is placed on a workbench and one end thereof is fixed, and then the expansion joint body 1 is continuously extended and retracted by an existing reciprocating drive component such as a cylinder. During the continuous extension and retraction process, the force applied to the expansion joint body 1 and the extension length are analyzed, thereby completing the fatigue test of the expansion joint body 1. This is an existing technology and will not be elaborated on. One of the core innovations of the embodiment of the present utility model is that a plurality of reciprocating test assemblies are arranged in an array on the expansion joint body 1. The reciprocating test assemblies are existing reciprocating drive structures such as electric push rods. The reciprocating test assemblies can be preferably arranged on the outer peripheral surface of the expansion joint body 1. According to the size of the diameter of the expansion joint body 1, different numbers of reciprocating test assemblies can be arranged in an array in the circumferential direction of the expansion joint body 1. That is, when the diameter of the expansion joint body 1 is smaller, the number of reciprocating test assemblies arranged is also smaller. On the contrary, when the diameter of the expansion joint body 1 is larger, the number of reciprocating test assemblies arranged is also more. A plurality of reciprocating test assemblies are used to synchronously apply force to the expansion joint body 1 so that the expansion joint body 1 can continuously expand and contract, thereby allowing fatigue tests to be performed on expansion joint bodies 1 of different diameters. Moreover, when the test is performed, it itself is not fixed at a specific position, so the test position can be adjusted at any time, and it is more flexible when used.

[0030] Preferably, the reciprocating test assembly is an oil cylinder 2. As the actuator of the test action, the oil cylinder 2 includes a cylinder barrel 3 and a piston rod 4 slidably arranged inside the cylinder barrel 3, and the other end of the piston rod 4 is connected to the upper end of the expansion joint body 1. Since the cylinder barrel 3 and the piston rod 4 are respectively fixed to the upper and lower ends of the expansion joint body 1, and the expansion joint body 1 has the ability to retract, when multiple piston rods 4 reciprocate synchronously, the expansion joint body 1 will reciprocate and retract in the axial direction, thereby realizing the stretching and return of expansion joint bodies 1 of different calibers during the fatigue test process.

[0031] Preferably, an upper support pipe 5 and a lower support pipe 6 are fixedly connected at both ends of the expansion joint body 1, an upper connecting piece 7 is provided on the upper support pipe 5, and a lower connecting piece 8 is provided on the lower support pipe 6, and the oil cylinder 2 is located between the upper connecting piece 7 and the lower connecting piece 8. Specifically, the upper support pipe 5 and the lower support pipe 6 are stepped tubular structures, that is, their side walls have two thicknesses, and the outer diameter of the thinner part is the same as the inner diameter of the expansion joint body 1. The outer wall of the port of the upper support pipe 5 is fixedly connected to the inner wall of the expansion joint body 1 near the top, and the outer wall of the port of the lower support pipe 6 is also fixedly connected to the inner wall of the expansion joint body 1 near the bottom. The outer wall of the upper support pipe 5 is fixedly connected with an upper connecting piece 7, which connects the upper support pipe 5 to the piston rod 4. Similarly, the lower connecting piece 8 connects the lower support pipe 6 to the cylinder 3. The purpose of such a setting is to set the upper support pipe 5 and the lower support pipe 6 at the port of the expansion joint body 1, To prevent the oil cylinder 2 from applying a force to the expansion joint body 1, which may cause deformation of the port of the expansion joint body 1, and when the piston rod 4 is extended or retracted, the upper connecting member 7 will be caused to reciprocate. Since the upper connecting member 7 is fixedly connected to the upper supporting pipe 5, and the upper supporting pipe 5 is connected to the top of the expansion joint body 1, the power of the oil cylinder 2 can be transmitted to the expansion joint body 1 through the upper connecting member 7, the lower connecting member 8, the upper supporting pipe 5 and the lower supporting pipe 6 to achieve the extension and retraction of the expansion joint body 1. In summary, the upper supporting pipe 5 and the lower supporting pipe 6 have a supporting function for the interior of the expansion joint body 1 and a transmission function for transmitting the power of the oil cylinder 2 to the expansion joint body 1.

[0032] Preferably, the upper connecting member 7 and the lower connecting member 8 are both L-shaped. Specifically, the upper connecting member 7 and the lower connecting member 8 are both plate-like structures with an L-shaped cross-section. The vertical edge of the upper connecting member 7 is fixedly connected to the upper support pipe 5 by multiple screws 9, and the bottom surface of the upper connecting member 7 is fixedly connected to the piston rod 4. Similarly, the pipe opening of the lower connecting member 8 is fixedly connected to the lower support pipe 6 by multiple screws 9, and the surface of the lower connecting member 8 close to the upper connecting member 7 is fixedly connected to the lower end surface of the cylinder 3. In this way, the upper support pipe 5 can be connected to the piston rod 4, and the cylinder 3 can be connected to the lower support pipe 6. The connection is made by screws 9, which is convenient for disassembly and adjustment of the number of reciprocating test assemblies.

[0033] In order to accurately measure the force applied to the expansion joint body 1, a pressure sensor 11 is provided at the output end of the oil cylinder 2. The pressure sensor 11 is provided on the end face of the piston rod 4. When the piston rod 4 reciprocates and applies force to the upper connecting member 7, causing the expansion joint body 1 to expand or contract, the pressure sensor 11 can measure the force applied to the upper connecting member 7, that is, the force applied to the expansion joint body 1.

[0034] Furthermore, a positioning sleeve 10 is fixedly connected to the output end of the oil cylinder 2. Specifically, the positioning sleeve 10 is fixedly connected to the piston rod 4 through a connecting block. The positioning sleeve 10 is cylindrical and is sleeved on the outside of the cylinder 3 and is slidably connected to the cylinder 3. When the oil cylinder 2 applies a force to the upper connecting member 7 to cause the expansion joint body 1 to expand and contract, it will simultaneously drive the positioning sleeve 10 to reciprocate. The cooperation between the cylinder 3 and the positioning sleeve 10 provides positioning of the expansion joint body 1 during the test to prevent the two ends of the expansion joint body 1 from offsetting during the test action.

[0035] In order to more accurately measure the telescopic length of the expansion joint body 1, a displacement sensor 12 is provided between the positioning sleeve 10 and the lower connecting member 8. Specifically, the upper end of the displacement sensor 12 is fixedly connected to the outer peripheral surface of the positioning sleeve 10, and the other end is fixedly connected to the surface of the lower connecting member 8 close to the upper connecting member 7. Since the positioning sleeve 10 is fixedly connected to the piston rod 4, when the piston rod 4 reciprocates, it will drive the positioning sleeve 10 to reciprocate synchronously with it. The displacement sensor 12 can measure the displacement of the reciprocating motion of the piston rod 4 through the positioning sleeve 10.

[0036] It should be noted that the force exerted by the cylinder 2 on the expansion joint body 1 is obtained through the pressure sensor 11, and the telescopic length of the expansion joint body 1 driven by the cylinder 2 is obtained through the displacement sensor 12. The obtained data are collected into the computer, and the "displacement-force" curve is drawn in real time to output complete test data.

[0037] Furthermore, an adjustable limiting mechanism is provided between the upper connecting member 7 and the lower connecting member 8. Specifically, the adjustable limiting mechanism can be a blocking block located within the movement range of the upper connecting member 7. When the piston rod 4 is extended and retracted to drive the upper connecting member 7 to move back and forth, the upper connecting member 7 abuts against the blocking block, preventing the upper connecting member 7 from continuing to move, thereby allowing the expansion joint body 1 to reciprocate within a limited range, thereby preventing the expansion joint body 1 from being overstretched.

[0038] Preferably, the adjustable limit mechanism includes a slide bar 13 fixed to the lower connecting member 8, the upper connecting member 7 is slidably connected to the slide bar 13, a limit member is provided on the slide bar 13, and the limit member is located on the movement stroke of the upper connecting member 7. Specifically, with respect to a reciprocating test assembly, two slide bars 13 are provided, the bottom end of the slide bar 13 passes through the lower connecting member 8 and is fixed thereto, a sliding hole is provided on the upper connecting member 7, the slide bar 13 is slidably connected to the sliding hole, and two limit members are provided on the slide bar 13, which can be divided into an upper limit member 14 and a lower limit member 15, the upper connecting member 7 is located between the upper limit member 14 and the lower limit member 15, and the positions of the upper limit member 14 and the lower limit member 15 on the slide bar 13 are adjustable, and the upper limit member 14 and the lower limit member 15 are both located on the movement stroke of the upper connecting member 7, and when the expansion joint body 1 is reciprocated and extended by the force applied by the oil cylinder 2, the upper connecting member 7 will be in contact with the expansion joint. The main body 1 performs synchronous reciprocating motion. When the upper connecting member 7 abuts against the upper limit member 14, the upper connecting member 7 cannot continue to move upward, so the expansion joint body 1 cannot continue to extend. Similarly, when the upper connecting member 7 abuts against the lower limit member 15, the lower connecting member 8 cannot continue to move downward, so the expansion joint body 1 cannot continue to contract. The effect of such a setting is that the slide rod 13 does not affect the movement of the expansion joint body 1 driven by the upper connecting member 7, while the upper limit member 14 and the lower limit member 15 enable the expansion joint body 1 to expand and contract within a limited range, effectively avoiding the expansion joint body 1 from damaging itself by stretching or shortening after being subjected to force.

[0039] Preferably, the distance between the upper connecting member 7 and the limit member is 10 mm. Specifically, when the expansion joint body 1 is stretched by tension to the point where the upper connecting member 7 abuts the upper limit member 14, the distance between the upper connecting member 7 and the lower limit member 15 is 10 mm. Similarly, when the expansion joint body 1 is stretched by tension to the point where the upper connecting member 7 abuts the lower limit member 15, the distance between the upper connecting member 7 and the upper limit member 14 is 10 mm, thereby allowing the expansion joint body 1 to expand and contract within a range of 10 mm.

[0040] As another embodiment of the present invention, an oil storage chamber 16 is defined within the upper connecting member 7, an oil outlet hole 17 is defined at the bottom of the oil storage chamber 16, a steel ball 18 is rotatably disposed within the oil outlet hole 17, and the steel ball 18 is in contact with the slide rod 13. Specifically, the oil storage chamber 16 is filled with lubricating oil, the oil outlet hole 17 connects the oil storage chamber 16 with the slide hole, and a spherical groove is defined at one end of the oil outlet hole 17 near the slide hole, within which the steel ball 18 is rotatably disposed. This configuration enables the steel ball 18 to move synchronously when the oil cylinder 2 drives the upper connecting member 7 to reciprocate and extend. Since the steel ball 18 is in contact with the slide rod 13, the upper connecting member 7 slides along the slide rod 13, driving the steel ball 18 to roll, thereby continuously delivering the lubricating oil within the oil storage chamber 16 to the slide hole (the oil supply method is similar to the ink delivery method of a ballpoint pen), thereby achieving passive lubrication of the slide rod 13.

[0041] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A multi-point, flexibly arranged fatigue test device for expansion joints, comprising an expansion joint body, characterized in that: A plurality of reciprocating test assemblies are arranged in an array on the expansion joint body.

2. A multi-point, flexibly arranged fatigue testing device for expansion joints according to claim 1, characterized in that: The reciprocating test component is an oil cylinder.

3. A multi-point, flexibly arranged fatigue testing device for expansion joints according to claim 2, characterized in that: An upper supporting tube and a lower supporting tube are fixedly connected to both ends of the expansion joint body respectively. An upper connecting piece is provided on the upper supporting tube, and a lower connecting piece is provided on the lower supporting tube. The oil cylinder is located between the upper connecting piece and the lower connecting piece.

4. A multi-point, flexibly arranged fatigue testing device for expansion joints according to claim 3, characterized in that: The upper connecting piece and the lower connecting piece are both L-shaped.

5. The multi-point, flexibly arranged fatigue testing device for expansion joints according to claim 2, characterized in that: The output end of the oil cylinder is provided with a pressure sensor.

6. The multi-point, flexibly arranged fatigue testing device for expansion joints according to claim 3, characterized in that: A positioning sleeve is fixedly connected to the output end of the oil cylinder.

7. The multi-point, flexibly arranged fatigue testing device for expansion joints according to claim 6, characterized in that: A displacement sensor is provided between the positioning sleeve and the lower connecting piece.

8. The multi-point, flexibly arranged fatigue testing device for expansion joints according to claim 3, characterized in that: An adjustable limiting mechanism is provided between the upper connecting member and the lower connecting member.

9. The multi-point, flexibly arranged fatigue testing device for expansion joints according to claim 8, characterized in that: The adjustable limiting mechanism includes a sliding rod fixedly connected to the lower connecting member, the upper connecting member is slidably connected to the sliding rod, and a limiting member is provided on the sliding rod, and the limiting member is located on the movement stroke of the upper connecting member.

10. The multi-point, flexibly arranged fatigue testing device for expansion joints according to claim 9, characterized in that: The distance between the upper connecting member and the limiting member is 10 mm.

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