Stretching detection equipment for pre-stretched connecting rod bolt

Abstract

The utility model is suitable for the technical field of connecting rods, and provides pre-stretching connecting rod bolt stretching detection equipment which comprises a top plate, a stretching assembly is installed at the bottom of the top plate, and the bottom of the stretching assembly is connected with a bottom plate; the stretching assembly comprises a stretching top plate, a plurality of sets of springs are arranged at the bottom of the stretching top plate, a stretching piece is arranged in the stretching top plate in a sleeved mode, and a pre-stretching module is arranged in the stretching piece in a sleeved mode; the pre-stretching module comprises a pre-stretching top plate, the bottom of the pre-stretching top plate is connected with two sets of pre-stretching hydraulic rods, and the output ends of the pre-stretching hydraulic rods are connected with pre-stretching bottom blocks. The device solves the problem that an actual stretching environment is difficult to simulate when the strength of a connecting rod bolt is detected, so that a dual stretching mode of the pre-stretching module and the main stretching module is adopted, and working condition changes in actual stretching assembly are effectively simulated through spring supporting and hydraulic rod control, so that the bolt is stressed more uniformly and deformed more controllably in the stretching process, and the strength of the bolt is detected. The detection precision is improved.

Description

Technical Field

[0001] This utility model relates to the field of connecting rod technology, and more specifically, it relates to a pre-tensioned connecting rod bolt tension testing device. Background Technology

[0002] The connecting rod is a crucial component in an engine, connecting the piston and crankshaft. During operation, it withstands complex alternating loads, thus placing high demands on its structural strength and connection reliability. As a key fastener connecting the connecting rod big end cap to the connecting rod body, the assembly quality of the connecting rod bolts directly affects the engine's operational safety and service life.

[0003] To ensure the stability of bolted connections, connecting rod bolts typically require high preload to maintain reliable connection under harsh conditions such as high speed and high load. Currently, connecting rod bolt assembly often employs a tension assembly process, which involves axially stretching the bolts using specialized equipment to induce plastic deformation before tightening the nuts to achieve the required preload. Some assembly processes even utilize a double tensioning process to further improve the uniformity and stability of the preload.

[0004] However, in practice, if the connecting rod bolts themselves have material defects or insufficient plastic deformation capacity, they may fracture during the tensile testing process. In severe cases, this can not only render the bolts unusable but also damage the equipment to be assembled, affecting the entire assembly process. Therefore, performing tensile testing on the connecting rod bolts before formal tensile assembly helps to identify potential fracture risks in advance, ensuring the safety and reliability of subsequent assembly processes.

[0005] To address the aforementioned issues, this application proposes a pre-tensioned connecting rod bolt tensile testing device for testing and screening the tensile properties of connecting rod bolts before formal assembly, thereby improving assembly quality and reducing the risk of failure. Utility Model Content

[0006] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a pre-tensioning connecting rod bolt tensioning device that ensures uniform force and stable operation during the tensioning process through a dual tensioning module design, spring support and hydraulic rod control, and prevents the bolt from breaking, deforming or becoming unstable during the tensioning process.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A pre-tensioned connecting rod bolt tensile testing device includes a top plate, a tensile assembly installed at the bottom of the top plate, and a bottom plate connected to the bottom of the tensile assembly.

[0009] The stretching assembly includes a stretching top plate, a plurality of springs are provided at the bottom of the stretching top plate, a stretching member is sleeved inside the stretching top plate, and a pre-stretching module is sleeved inside the stretching member.

[0010] The pre-stretching module includes a pre-stretching top plate, and two sets of pre-stretching hydraulic rods are connected to the bottom of the pre-stretching top plate. The output end of the pre-stretching hydraulic rods is connected to a pre-stretching bottom block.

[0011] The present invention is further configured such that: the spring is arranged vertically and surrounds the tension member, the tension member is configured as a hollow structure, and the inner diameter of the upper half of the tension member is larger than the inner diameter of the lower half.

[0012] The present invention is further configured such that: the two sets of pre-stretched top plates are symmetrically arranged along the axial direction of the pre-stretched module, and the pre-stretched bottom block is configured as a cylindrical structure.

[0013] The present invention is further configured such that: a flange is provided on the top of the pre-stretched bottom block, and the diameter of the flange is larger than the inner diameter of the lower half of the stretching member.

[0014] The present invention is further configured such that: a tension block is connected to the bottom of the spring, a fixing member is snapped to the bottom of the tension block, a tension cavity is provided between the tension block and the fixing member, and the tension member can slide axially inside the tension cavity.

[0015] The present invention is further configured such that: the top plate has a plurality of sets of fixing holes, and each set of fixing holes is fitted with bolts for connecting the top plate and the tensioning assembly.

[0016] The present invention is further configured such that: mounting holes are respectively opened on both sides of the top plate, and hydraulic rods are installed at the mounting holes, with the output end of the hydraulic rods connected to the top of the bottom plate.

[0017] In summary, this application includes at least one of the following beneficial technical effects:

[0018] 1. This implementation method simulates the two stretching processes in actual assembly by setting up a pre-stretching module and a main stretching hydraulic rod. It adopts a staged stretching strategy, first applying an initial stretching force to the connecting rod bolt, and then the main stretching module completes the final shaping. This process can effectively reproduce the actual stretching conditions, making the bolt more continuously and stably stressed throughout the entire testing process, improving the authenticity and reliability of the test results, and better meeting actual assembly requirements.

[0019] 2. This implementation method adopts a spring-assisted support, replaceable fasteners, and stepped tensioning component structure design, which not only enables the equipment to quickly adapt to connecting rod bolts of different specifications, but also improves the smoothness of the tensioning stroke and the stability of operation through the rebound force and buffering effect provided by the spring, reduces the risk of jamming and deflection during bolt tensioning operations, and enhances the versatility and applicability of the equipment. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a pre-tensioned connecting rod bolt tension testing device according to the present invention.

[0021] Figure 2 This is a schematic diagram of the tensioning component in this utility model.

[0022] Figure 3 This is the front view of the stretching component in this utility model.

[0023] Figure 4 for Figure 3 A sectional view taken along section line AA.

[0024] Explanation of reference numerals in the attached drawings: 1. Top plate; 11. Fixing hole; 12. Mounting hole;

[0025] 2. Tensioning assembly; 21. Tensioning top plate; 22. Pre-tensioning module; 221. Pre-tensioning top plate; 222. Pre-tensioning hydraulic rod; 223. Pre-tensioning bottom block; 224. Flange; 23. Spring; 24. Tensioning bottom block; 241. Tensioning cavity; 25. Tensioning component; 26. Fixing component;

[0026] 3. Base plate;

[0027] 4. Hydraulic rod. Detailed Implementation

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0030] Example 1, please refer to Figure 1-4 The present invention provides the following technical solution:

[0031] This embodiment specifically refers to a pre-tensioned connecting rod bolt tension testing device, as shown in the figure. It includes a top plate 1, and a tensioning component 2 is installed at the bottom of the top plate 1. The tensioning component 2 is cylindrical and arranged vertically. The bottom of the tensioning component 2 is connected to a base plate 3 to form a stable overall support structure, so that the device can remain stable during the tensioning process and avoid shaking or displacement.

[0032] The tensioning assembly 2 includes a tensioning top plate 21. Several sets of springs 23 are evenly installed on the bottom of the top plate 21. The springs 23 are arranged vertically and surround the tensioning member 25. The springs 23 provide continuous auxiliary support and rebound force to the tensioning member 25 during the tensioning process, preventing the tensioning assembly from swaying or rebounding due to uneven force distribution, thus improving the stability and reliability of the tensioning operation.

[0033] The tensioning top plate 21 is internally fitted with a tensioning member 25. The tensioning member 25 is a hollow cylindrical structure with a stepped internal structure, meaning the inner diameter of the upper half is larger than that of the lower half, forming a clear transition area. A stepped surface is formed at the connection between the upper and lower halves, and this stepped surface abuts against the upper surface of the tensioning top plate 21. This structural design facilitates the partitioned installation of different functional modules and allows the tensioning member 25 to move smoothly during the tensioning process, avoiding jamming or force misalignment and improving the overall reliability of the device.

[0034] The tensioning component 25 has a pre-tensioning module 22 inside. The pre-tensioning module 22 is used to perform preliminary tensioning on the connecting rod bolts before the formal tensioning, improving tensioning accuracy and bolt connection quality. The pre-tensioning module 22 includes a pre-tensioning top plate 221. Two sets of pre-tensioning hydraulic rods 222 are connected to the bottom of the pre-tensioning top plate 221. The two sets of pre-tensioning hydraulic rods 222 are symmetrically arranged along the axial direction of the pre-tensioning module 22 to ensure uniform force distribution during pre-tensioning and avoid eccentric loading. The output ends of the two sets of pre-tensioning hydraulic rods 222 are respectively connected to pre-tensioning bottom blocks 223.

[0035] The pre-stretch base block 223 is preferably a cylindrical structure, and its top is provided with a flange 224. The diameter of the flange 224 is larger than the inner diameter of the lower half of the stretching member 25. By setting the flange 224, effective limiting can be achieved in the stretching operation, ensuring smooth and stable docking between the pre-stretch module 22 and the stretching member 25, and ensuring that the pre-stretch base block 223 does not move downward, but the pre-stretch top plate 221 is stretched upward, preventing component misalignment or decreased stretching accuracy caused by poor docking.

[0036] In actual use, the tensioning operation of the connecting rod bolt is as follows: First, the pre-tensioning module 22 is activated, and the two sets of pre-tensioning hydraulic rods 222 are synchronously controlled to extend synchronously, thereby gradually increasing the axial distance between the pre-tensioning top plate 221 and the pre-tensioning bottom block 223. During this process, a predetermined initial tensioning force is applied to the connecting rod bolt, completing the pre-tensioning stage of the bolt. After pre-tensioning is completed, the pre-tensioning hydraulic rods 222 continue to maintain the applied force to ensure that the initial tensioning force of the connecting rod bolt does not loosen, preventing the pre-tensioning effect from disappearing due to the interruption of force.

[0037] Subsequently, the main tensioning stage begins. The hydraulic rod 4 starts working, applying axial thrust to the top plate 1, which further drives the top plate 1 to move vertically, thus achieving formal tensioning and shaping of the connecting rod bolt, so that the bolt reaches the designed tensile stress and is tightened.

[0038] It should be noted that the hydraulic rod 4 is specifically used for applying the main tensile force. One end of the hydraulic rod 4 is fixedly installed on both sides of the top plate 1 through the mounting hole 12, and the output end of the other end is connected to the top of the bottom plate 3. Through the extension and retraction of the hydraulic rod 4, the bottom plate 3 can move controllably relative to the top plate 1 in the vertical direction, thereby applying the required main tensile force to the connecting rod bolt. Therefore, the entire connecting rod bolt tensioning process is completed in two steps: first, the pre-tensioning module 22 performs preliminary tensioning, and then the hydraulic rod 4 performs the main tensioning, ensuring that the force during the tensioning process is continuous and controllable. This process can effectively reproduce the actual tensioning conditions, making the bolt more continuously and stably stressed throughout the entire testing process, improving the authenticity and reliability of the test results, and better meeting actual assembly requirements.

[0039] Furthermore, the lower end of the spring 23 is connected to a tension base 24, the bottom of which has a structure for snap-fit ​​connection with the fixing member 26. Specifically, when the fixing member 26 needs to be installed, it is inserted axially into the tension base 24, and then a quick and stable connection is achieved through the snap-fit ​​structure inside the tension base 24, making it convenient and fast. The fixing member 26 has a threaded hole structure inside, allowing the connecting rod bolt to be screwed in and fixed, thus ensuring accurate positioning and reliable connection of the connecting rod bolt during the tensioning process, preventing loosening or displacement of the bolt. At the same time, to accommodate different specifications and models of connecting rod bolts, the fixing member 26 can be quickly replaced as needed, greatly improving the adaptability and practical range of this equipment.

[0040] A tensioning cavity 241 is formed between the tensioning base block 24 and the fixing member 26. The tensioning member 25 can slide freely along the axial direction in the tensioning cavity 241, which further ensures the flexibility of the tensioning member 25 during the force application process and the smoothness of the tensioning stroke, avoids the occurrence of jamming, lateral force and other phenomena, and ensures the stability and efficiency of the tensioning operation.

[0041] In addition, to facilitate the stable installation and fixation of the tensioning assembly 2, several sets of fixing holes 11 are provided on the top plate 1. Each set of fixing holes 11 is equipped with bolts, which can firmly connect the top plate 1 and the tensioning assembly 2 together, further improving the rigidity, stability and impact resistance of the overall structure, and ensuring the safety and reliability of the equipment under high load tension conditions.

[0042] Obviously, the embodiments described above are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

Claims

1. A tensile testing device for pre-tensioned connecting rod bolts, characterized in that: Includes a top plate (1), a tensioning assembly (2) is installed at the bottom of the top plate (1), and a bottom plate (3) is connected to the bottom of the tensioning assembly (2); The tensioning assembly (2) includes a tensioning top plate (21), a plurality of springs (23) are provided at the bottom of the tensioning top plate (21), a tensioning member (25) is sleeved inside the tensioning top plate (21), and a pre-tensioning module (22) is sleeved inside the tensioning member (25). The pre-stretching module (22) includes a pre-stretching top plate (221), and two sets of pre-stretching hydraulic rods (222) are connected to the bottom of the pre-stretching top plate (221). The output end of the pre-stretching hydraulic rods (222) is connected to a pre-stretching bottom block (223).

2. The pre-tensioned connecting rod bolt tensile testing equipment according to claim 1, characterized in that: The spring (23) is arranged vertically and surrounds the tension member (25). The tension member (25) is a hollow structure, and the inner diameter of the upper half of the tension member (25) is larger than the inner diameter of the lower half.

3. The pre-tensioned connecting rod bolt tensile testing equipment according to claim 1, characterized in that: The two sets of pre-stretched top plates (221) are symmetrically arranged along the axial direction of the pre-stretched module (22), and the pre-stretched bottom block (223) is configured as a cylindrical structure.

4. The pre-tensioned connecting rod bolt tensile testing equipment according to claim 1, characterized in that: The pre-stretched base block (223) is provided with a flange (224) at the top, and the diameter of the flange (224) is larger than the inner diameter of the lower half of the stretching member (25).

5. The pre-tensioned connecting rod bolt tensile testing equipment according to claim 1, characterized in that: The bottom of the spring (23) is connected to a tension block (24), and the bottom of the tension block (24) is connected to a fastener (26). A tension cavity (241) is provided between the tension block (24) and the fastener (26), and the tension member (25) can slide axially inside the tension cavity (241).

6. The pre-tensioned connecting rod bolt tensile testing equipment according to claim 1, characterized in that: The top plate (1) has several sets of fixing holes (11), and each set of fixing holes (11) is fitted with bolts for connecting the top plate (1) and the tensioning assembly (2).

7. The pre-tensioned connecting rod bolt tensile testing equipment according to claim 6, characterized in that: Mounting holes (12) are provided on both sides of the top plate (1), and hydraulic rods (4) are installed in the mounting holes (12). The output end of the hydraulic rods (4) is connected to the top of the bottom plate (3).

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