Studying heat-affected zone deformations of electric arc welding

International Conference on Mechanical Engineering, Automation and Control Systems 2017

机械制造;无线电电子学;计算机科学

Suleimanov, R.I.^1 ; Zainagalina, L.Z.^1 ; Khabibullin, M.Ya.^1 ; Zaripova, L.M.^1 ; Kovalev, N.O.^1

Ufa State Petroleum Technological University, Branch of the University in the City of Oktyabrsky, Republic of Bashkortostan, Devonskaya St., 54a, Oktyabrsky

452607, Russia^1

关键词: Crystalline structure;    Molten filler;    Oil pipelines;    Pipe material;    Rockwell hardness;    Strength characteristics;    Thermal actions;    Welded structures;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/327/3/032053/pdf
DOI  :  10.1088/1757-899X/327/3/032053

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

The paper studies the influence of the most common defects in permanent electric arc welds made during the welding butt joints in infield oil pipelines, onto the strength characteristics of the welded pipe material around the heat-affected zone. A specimen of a butt weld with an obvious defect was used as a subject of the study. The changes in the geometric parameters of the weld were measured with the standard means; Rockwell hardness in the heat-affected zone was determined in certain areas with justification for the weld process modes. The cause of softening was found to be an increased width of the hot spot on the one side of the weld, where an enlarged crystalline structure appears as a result of the pipe material recrystallization under the influence of heat. Changes in the geometry of the thermal action area are determined by accumulation of molten filler on the one side of the weld when the welding rate is decreased. Some recommendations are given to prevent destruction of the welded structures and appearance of emergencies in infield oil pipelines.