Horajski Piotr, Bohdal Lukasz, Kukielka Leon, Patyk Radoslaw, Kaldunski Pawel, Legutko Stanislaw
Faculty of Mechanical Engineering, Koszalin University of Technology, 75-620 Koszalin, Poland.
Faculty of Mechanical Engineering, Poznan University of Technology, 60-965 Poznan, Poland.
Materials (Basel). 2021 Jan 21;14(3):504. doi: 10.3390/ma14030504.
The article presents an innovative method of reducing welding distortions of thin-walled structures by introducing structural and technological changes. The accuracy of the method was demonstrated on the example of welding the stub pipes to the outer surface of a thin-walled tank with large dimensions, made of steel 1.4301 with a wall thickness of 1.5 × 10 (m). During traditional Gas Tungsten Arc Welding (GTAW), distortions of the base are formed, the flatness deviation of which was 11.9 × 10 (m) and exceeded the permissible standards. As a result of structural and technological changes, not only does the joint stiffness increase, but also a favorable stress state is introduced in the flange, which reduces the local welding stresses. Numerical models were developed using the finite element method (FEM), which were used to analyze the residual stresses and strains pre-welding, in extruded flanges, in transient, and post-welding. The results of the calculations for various flanges heights show that there is a limit height h = 9.2 × 10 (m), above which flange cracks during extrusion. A function for calculating the flange height was developed due to the required stress state. The results of numerical calculations were verified experimentally on a designed and built test stand for extrusion the flange. The results of experimental research confirmed the results of numerical simulations. For further tests, bases with a flange h = 6 × 10 (m) were used, to which a stub pipe was welded using the GTAW method. After the welding process, the distortion of the base was measured with the ATOS III scanner (GOM a Zeiss company, Oberkochen, Germany). It has been shown that the developed methodology is correct, and the introduced structural and technological changes result in a favorable reduction of welding stresses and a reduction in the flatness deviation of the base in the welded joint to 0.39 × 10 (m), which meets the requirements of the standards.
本文介绍了一种通过引入结构和工艺变化来减少薄壁结构焊接变形的创新方法。该方法的准确性在将短管焊接到由壁厚为1.5×10（米）的1.4301钢制成的大尺寸薄壁罐外表面的示例中得到了证明。在传统的钨极气体保护电弧焊（GTAW）过程中，基体产生了变形，其平面度偏差为11.9×10（米），超过了允许标准。由于结构和工艺的变化，不仅接头刚度增加，而且法兰中引入了有利的应力状态，从而降低了局部焊接应力。使用有限元方法（FEM）开发了数值模型，用于分析焊接前、挤压法兰中、瞬态和焊接后的残余应力和应变。各种法兰高度的计算结果表明，存在一个极限高度h = 9.2×10（米），超过该高度，法兰在挤压过程中会出现裂纹。根据所需的应力状态开发了一个计算法兰高度的函数。数值计算结果在设计和建造的法兰挤压试验台上进行了实验验证。实验研究结果证实了数值模拟结果。为了进行进一步的测试，使用了法兰高度h = 6×10（米）的基体，采用GTAW方法将短管焊接到该基体上。焊接过程完成后，使用ATOS III扫描仪（德国奥伯科亨的蔡司公司GOM）测量基体的变形。结果表明，所开发的方法是正确的，引入的结构和工艺变化导致焊接应力得到了有利的降低，并且焊接接头中基体的平面度偏差降低到了0.39×10（米），符合标准要求。
