Investigation on Non-Preheating Welding Technology of X70 Pipeline Steel

Abstract:

Considering the mechanical properties of X70 pipeline steel after repeated welding heat cycles, preheating and interpass temperature controlling are often adopted in the welding technology, which widely increase the welding construction time and lower the construction efficiency, thus improve the construction cost of pipelines. According to the present welding process of X70 pipeline steel, non-preheating welding technology was proposed in this paper. The experiment results show that the properties of the weld joint of X70 pipeline steel with non-preheating achieves the requirement of specified standard. Furthermore, this method simplifies the welding construction processes and improves the construction efficiency. Key Words:X70 Steel; Non-Preheating; Welding Technology

• Periodical: Applied Mechanics and Materials (Volumes 333-335)
• Pages: 1836-1840
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.333-335.1836
• Online since: July 2013
• Authors: De Fen Zhang, Jin Wang, Zheng Tao Jiang, Xiong Shi, Zeng Zhen Li, Xin Zeng
• Keywords: Non-Preheating, Welding Technology, X70 Steel

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