高钢级油气输送管道环焊缝双丝焊接技术的应用

Application of Dual-wire Welding Process to Boxig of High-grade Oil/Gas Pipeline

简介了输送管线的传统焊接工艺,以X80和X100级管线钢熔化极气体保护焊(GMAW)为例,讨论了高钢级管线钢焊接时存在的主要问题,并对比分析了X80级管线钢单丝焊和双丝焊的接头力学性能差别。侧重介绍了双丝焊工作原理及其优点,以及双丝焊接技术在某海底管线敷设中的应用情况。结果表明,高钢级管线钢环焊缝现场焊接时采用双丝焊接技术,不仅可以提高焊缝质量和焊接效率,而且可以降低焊接热影响区组织粗化和软化程度,有利于焊接接头力学性能的改善。

The conventional welding process for pipeline. Taking the GMAW of the X80 and X110 linepipe steels as an example, the co-authors of the paper have a discussion on the main problems involving welding of high-grade linepipe steels, and a comparative analysis with respect to the difference between the mechanical properties of the welding joints respectively resulting from the single-wire welding process and the said dual-wire welding process as applied to welding of the X80 linepipe steel. And the work principle and advantages of the dualwire welding process are elaborated. Also described in the paper is the successful application of the said dual-wire welding process to the construction of a certain submarine pipeline. The operation practice leads to such a conclu- sion that in case of site boxig of the high-grade linepipe steel, the employment of the dual-wire welding process will not only improve both the welding quality and operation efficiency, but also reduce the degree of the steel structural coursing and softening of the heat-effected area under the welding so as to get the mechanical properties of the weld joint improved.