A welding crack test device and apparatus
By designing a welding crack testing device with a restraint frame and test fixtures, the problem of difficulty in quantitatively analyzing the restraint stress in existing welding delayed crack testing methods has been solved, achieving efficient and accurate welding test results. It is applicable to the delayed crack G-BOP test of high-strength steel.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- OFFSHORE OIL ENG CO LTD
- Filing Date
- 2025-06-06
- Publication Date
- 2026-07-10
AI Technical Summary
Existing methods for testing delayed weld cracks lack clearly defined welding fixtures, making it difficult to quantitatively analyze the restraint stress level, resulting in poor reproducibility and accuracy. Furthermore, these methods are inconvenient to install and the applied restraint stress is poorly aligned, thus affecting the test results.
A welding crack testing device was designed, including a restraint frame and a testing fixture. The moving unit and the testing unit are connected by multiple restraint spaces and thrust ball bearings. The device can accurately and quantitatively apply restraint stress through the threaded part and torque wrench, ensuring that the test weld is subjected to uniform stress and has good centering.
It enables accurate and quantitative application of restraint stress to high-strength steel welded joints, improving the reproducibility and accuracy of the test. It has high welding test efficiency, simple structure and convenient operation, and is suitable for welding test plates with a thickness of 20-200mm.
Smart Images
Figure CN224480347U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of welding testing technology, and in particular relates to a welding crack testing device and equipment. Background Technology
[0002] High-strength steel is widely used in marine engineering equipment, large ships, bridges, pressure vessels, machinery, and large steel structures. Welding is an indispensable key technology in the manufacturing of various high-strength steel equipment and structures. Welding cold cracking defects, especially delayed cracking, frequently occur in the welding process of high-strength steel. Delayed cracking in welded joints is mainly related to the hardening tendency of the material, the hydrogen content and distribution in the weld, the restraint degree of the weld joint, and the stress state. It is generally believed that delayed cracking is a welding crack caused by the combined effects of plasticity reserve, stress state, and hydrogen content in the weld metal. Delayed cracking has three stages: a latency period, a slow propagation period, and a sudden fracture period. Welded delayed cracking has a certain latency, and may appear hours, days, or even longer after welding. Therefore, the appearance of delayed cracks in welded joints poses a significant threat to structural safety. Moreover, the tendency for delayed cracking in welded joints increases with the strength and thickness of the high-strength steel.
[0003] To prevent and control delayed cracking in high-strength steel welded joints, delayed crack testing and evaluation experiments are frequently conducted before welding. Currently widely used methods for testing and evaluating delayed cracking include: oblique Y-groove butt joint crack test, window-type restraint crack test, rigid restraint crack test, pin test, and transverse crack G-BOP test. Among these, the oblique Y-groove butt joint crack test, window-type restraint crack test, rigid restraint crack test, and pin test all have clearly defined welding fixture requirements. However, the transverse crack G-BOP test lacks specific welding fixture requirements and only requires the application of a certain restraint, without a method for quantitatively analyzing the restraint stress level, resulting in poor reproducibility and accuracy of the test results. Furthermore, the commonly used transverse crack G-BOP test welding fixture is inconvenient to install, and the applied restraint stress has poor alignment. Therefore, there is an urgent need for a high-strength steel welded joint delayed crack G-BOP test welding fixture that can accurately and quantitatively apply restraint stress, is easy to install, has good alignment, and high testing efficiency.
[0004] Therefore, there is an urgent need to design a welding crack testing device and equipment to solve the problems mentioned above. Utility Model Content
[0005] To address the technical problems mentioned in the background art, such as the lack of specific welding fixtures for crack testing, the inability to quantitatively analyze the restraint stress level during testing, resulting in poor reproducibility and accuracy of test results, inconvenient installation, and poor alignment of applied restraint stress, a welding crack testing device and equipment are provided.
[0006] To achieve the above objectives, the specific technical solution of the welding crack testing device and equipment of this utility model is as follows:
[0007] A welding crack testing device includes a restraint frame with several restraint spaces within it. Each restraint space is used to accommodate a welding test plate with a test weld. The restraint frame has through holes, with one through hole corresponding to each restraint space. The device also includes multiple testing fixtures, each comprising a testing unit and a moving unit. All testing fixtures pass through the through holes. The testing unit is located within a restraint space, and the moving unit passes through the through holes. The moving unit can rotate relative to the through holes and drive the testing unit closer to the welding test plate to perform a compression test on the welding test plate.
[0008] Furthermore, the test fixture also includes a thrust ball bearing, which connects the moving unit and the test unit respectively.
[0009] Furthermore, the moving unit includes a threaded portion, one end of which is rotatably connected to a thrust ball bearing, and the through hole is configured as a threaded hole, with the threaded portion rotatably connected to the threaded hole.
[0010] Furthermore, the central axis of the threaded hole is parallel to the width direction of the restraint frame.
[0011] Furthermore, the moving unit also includes an end screw head, which is located at the end of the threaded portion where the thrust ball bearing is not connected, and the end screw head is located outside the restraint frame.
[0012] Furthermore, the welding crack testing device also includes a base plate, a restraint frame connected to the base plate and disposed around the base plate, and multiple partitions disposed within the restraint frame to form several restraint spaces.
[0013] Furthermore, the base plate is a rectangular steel plate with adjustable support legs and leveling feet at the four corners, which can be used to adjust the height and flatness of the base plate.
[0014] Furthermore, the thickness of the partition is the same as that of the restraint frame, and they are evenly distributed to form multiple independent restraint spaces.
[0015] Furthermore, the restraint frame is equipped with lifting lugs on both sides for hoisting or transporting.
[0016] A welding crack testing device, which uses the welding crack testing apparatus as described above.
[0017] The welding crack testing device of this utility model has the following advantages: it can be used for delayed crack G-BOP tests on welded test plates with a thickness of 20-200mm, with a wide applicable thickness range; it adopts a restraint frame containing multiple restraint spaces, which can simultaneously carry out delayed crack tests on multiple welded test plates, resulting in high welding test efficiency; the test fixture uses a moving unit and a testing unit to apply pressure to the welded test plate, ensuring uniform stress on the test weld, and the testing unit will not shift vertically during loading, resulting in good centering; the entire welding fixture has the advantages of simple structure and convenient operation.
[0018] The welding crack testing equipment of this invention has the following advantages: The equipment can be used with a torque wrench at the outer end of the threaded section to apply different restraint stresses, accurately adjusting the restraint level of the test weld. The threaded section is connected to the test unit via a thrust ball bearing, converting the circumferential stress applied by the rotation of the threaded section into horizontal stress acting on the test unit, which is then applied to the welding test plate, ensuring uniform stress on the test weld. Furthermore, the test unit does not shift vertically during loading, ensuring good centering. The entire welding fixture has a simple structure and is easy to operate. The lifting lugs on both sides of the restraint frame are compatible with forklifts, making handling more convenient. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the welding crack testing device of this utility model;
[0020] Figure 2 This is a schematic diagram of the welding crack testing device of this utility model when no welding test plate is provided;
[0021] Figure 3 This is a schematic diagram of the restraint frame of this utility model;
[0022] Figure 4 This is a schematic diagram of the structure of the test fixture of this utility model;
[0023] Figure 5 This is a cross-sectional view of the test fixture of this utility model.
[0024] Explanation of markings in the diagram:
[0025] 1. Base plate; 2. Restraint frame; 3. Threaded part; 4. Thrust ball bearing; 5. Test unit; 6. Liftable support leg; 7. Leveling foot; 8. Partition plate; 9. Restraint space; 10. Threaded hole; 11. Lifting lug; 12. End screw head; 13. Welding test plate; 14. Test weld. Detailed Implementation
[0026] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0027] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.
[0028] The following is a reference to the appendix. Figure 1 To be continued Figure 5 This invention describes a welding crack testing device and equipment.
[0029] This embodiment provides a welding crack testing device. Figure 1 This is a schematic diagram of the welding crack testing device in this embodiment; Figure 2 This is a schematic diagram of the welding crack testing device in this embodiment when no welding test plate is provided; Figure 3 This is a schematic diagram of the restraint frame in this embodiment; as shown Figures 1-3 As shown, the welding crack testing device includes a restraint frame 2, which contains several restraint spaces 9. Each restraint space 9 is used to accommodate a welding test plate 13. The welding test plate 13 has a test weld 14. The restraint frame 2 has through holes, and each restraint space 9 has a corresponding through hole. The welding crack testing device also includes multiple test fixtures, each of which includes a test unit 5 and a moving unit. All test fixtures pass through the through holes. The test unit 5 is located within the restraint space 9, and the moving unit passes through the through holes. The moving unit can rotate relative to the through holes and drive the test unit 5 to approach the welding test plate 13 to perform a compression test on the welding test plate 13.
[0030] This welding crack testing device can be used for delayed crack G-BOP tests on welded test plates 13 with a thickness of 20-200mm, with a wide range of applicable thicknesses. It adopts a restraint frame 2 containing multiple restraint spaces 9, which can simultaneously carry out delayed crack tests on multiple welded test plates 13, resulting in high welding test efficiency. The test fixture uses a moving unit and a testing unit 5 to apply pressure to the welded test plate 13, ensuring uniform stress on the test weld 14. Moreover, the testing unit 5 will not shift vertically during loading, ensuring good centering. The entire welding fixture has the advantages of simple structure and convenient operation.
[0031] Figure 4 This is a schematic diagram of the test fixture in this embodiment; Figure 5 This is a cross-sectional view of the test fixture in this embodiment.
[0032] Furthermore, such as Figure 4 and Figure 5 As shown, the test fixture also includes a thrust ball bearing 4, which connects the moving unit and the test unit 5. The thrust ball bearing 4 converts rotational motion into linear pressure, reducing frictional loss and improving force application accuracy; it also prevents the test unit 5 from shifting due to uneven rotational force, ensuring horizontal force application.
[0033] Preferably, the diameter of the thrust ball bearing 4 is at least 80% of the width of the test unit 5.
[0034] Furthermore, such as Figures 3-5 As shown, the moving unit includes a threaded part 3, one end of which is rotatably connected to a thrust ball bearing 4. The through hole is configured as a threaded hole 10, and the threaded part 3 is rotatably connected to the threaded hole 10. Fine-tuning pressure is achieved through threaded engagement, facilitating control of the restraint stress level. The threaded structure is simple and reliable, and easy to achieve manual or tool-driven operation.
[0035] Furthermore, the central axis of the threaded hole 10 is parallel to the width direction of the restraint frame 2 to ensure that the pressure is evenly distributed along the thickness direction of the welding test plate 13, and to avoid lateral force interference with the test results.
[0036] Furthermore, such as Figure 4 and Figure 5 As shown, the moving unit also includes an end screw head 12, which is located at the end of the threaded portion 3 where the thrust ball bearing 4 is not connected, and is located outside the restraint frame 2. The end screw head 12 (e.g., hexagonal design) can be used with a torque wrench to achieve quantitative force application and improve test repeatability.
[0037] Preferably, the end screw 12 is an internal hexagon or external hexagon, which can be used with a torque wrench to apply torque.
[0038] Furthermore, the welding crack testing device also includes a base plate 1, a restraint frame 2 connected to the base plate 1 and disposed around the base plate 1, and a plurality of partitions 8 disposed within the restraint frame 2 to form several restraint spaces 9.
[0039] Specifically, the base plate 1 is a rectangular steel plate with adjustable support legs 6 and leveling feet 7 at the four corners, which can be used to adjust the height and flatness of the base plate 1.
[0040] Preferably, the thickness of the base plate 1 is 20-50mm, and the four corners of the base plate 1 are provided with liftable support legs 6 and leveling feet 7.
[0041] Furthermore, the thickness of the partition 8 is the same as that of the restraint frame 2, and they are evenly distributed to form multiple independent restraint spaces 9.
[0042] Understandably, the partitions 8 are evenly spaced to form independent spaces, supporting testing of test plates of different sizes. The liftable support legs 6 and leveling feet 7 ensure the device is horizontal and stable, adapting to different site requirements.
[0043] Preferably, the restraint frame 2 plate is 20-50mm thick, and the space inside a single restraint frame is 230-300mm long, 150-200mm wide, and 50-150mm high.
[0044] Preferably, the test unit 5 is 20-30mm thick, its length is at least 20mm longer than the width of the welding test plate 13, its length on one side is ≥10mm, and its width is at least 20mm longer than the thickness of the welding test plate 13, so as to ensure that the welding test plate 13 is subjected to uniform force.
[0045] Furthermore, the restraint frame 2 is provided with lifting lugs 11 on both sides for hoisting or transportation.
[0046] The testing process of this welding crack testing device includes:
[0047] 1. Place the four processed welding test plates 13, each with dimensions of 200mm in length × 150mm in width × 50mm in thickness, into the four restraint spaces 9 of the restraint frame 2 respectively;
[0048] 2. Adjust the welding test plate 13 to fit against the side wall of the restraint space 9, and use a torque wrench to connect the end screw head 12 and rotate it; as the threaded part 3 rotates forward, it pushes the thrust ball bearing 4 to rotate, converting the circumferential clamping force of the rotation into a horizontal clamping force and transmitting it to the test unit 5, so that the test unit 5 moves in the horizontal direction and clamps the welding test plate 13 until the torque wrench shows that the set torque has been reached;
[0049] 3. After the welding test plate 13 is installed and fixed, a welding test is carried out at the test weld 14 according to the specified welding process to obtain the required test weld 14. Single-pass welds or multiple-pass welds can be welded.
[0050] 4. After welding is completed, keep it under the restraint and clamping force for 48 hours, then use an Allen wrench to turn the end screw 12 to loosen the thread 3 and remove the welding test plate 13.
[0051] 5. Conduct corresponding delayed crack detection and evaluation on the test weld 14 on the welding test plate 13.
[0052] This embodiment also provides a welding crack testing device, which uses the welding crack testing apparatus as described above. This welding crack testing device can be coupled with a torque wrench at the outer end of the threaded portion 3 to apply different restraint stresses, accurately adjusting the restraint level of the test weld 14. The threaded portion 3 is connected to the test unit 5 via a thrust ball bearing 4, converting the circumferential stress applied by the rotation of the threaded portion 3 into horizontal stress acting on the test unit 5, and then applied to the welding test plate 13 through the test unit 5, ensuring uniform stress on the test weld 14. Furthermore, the test unit 5 does not shift vertically during loading, ensuring good centering. The entire welding fixture has a simple structure and is easy to operate. Moreover, the lifting lugs 11 on both sides of the restraint frame 2 are compatible with forklifts, making transportation more convenient.
[0053] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.
Claims
1. A welding crack testing device, characterized in that, The device includes a restraint frame containing several restraint spaces for accommodating welding test plates. Each welding test plate has a test weld. The restraint frame has through holes, with one through hole corresponding to each restraint space. The welding crack testing device also includes multiple testing fixtures, each consisting of a testing unit and a moving unit. All testing fixtures pass through the through holes. The testing unit is located within the restraint space, and the moving unit passes through the through holes. The moving unit can rotate relative to the through holes and drive the testing unit closer to the welding test plate to perform a compression test on the welding test plate.
2. The welding crack testing device according to claim 1, characterized in that, The test fixture also includes a thrust ball bearing, which connects the moving unit and the test unit respectively.
3. The welding crack testing device according to claim 2, characterized in that, The moving unit includes a threaded part, one end of which is rotatably connected to a thrust ball bearing. The through hole is configured as a threaded hole, and the threaded part is rotatably connected to the threaded hole.
4. The welding crack testing device according to claim 3, characterized in that, The central axis of the threaded hole is parallel to the width direction of the restraint frame.
5. The welding crack testing device according to claim 3, characterized in that, The moving unit also includes an end screw head, which is located at the end of the threaded portion that is not connected to the thrust ball bearing, and the end screw head is located outside the restraint frame.
6. The welding crack testing apparatus according to claim 1, characterized in that, The welding crack testing device also includes a base plate, a restraint frame connected to the base plate and set around the base plate, and multiple partitions set inside the restraint frame to form several restraint spaces.
7. The welding crack testing apparatus according to claim 6, characterized in that, The base plate is a rectangular steel plate with adjustable support legs and leveling feet at the four corners, which can be used to adjust the height and flatness of the base plate.
8. The welding crack testing apparatus according to claim 6, characterized in that, The thickness of the partition is the same as that of the restraint frame, and they are evenly distributed to form multiple independent restraint spaces.
9. The welding crack testing apparatus according to any one of claims 1, 6, or 7, characterized in that, The restraint frame has lifting lugs on both sides for hoisting or transporting.
10. A welding crack testing device, characterized in that, The welding crack testing apparatus as described in any one of claims 1-9 was used.