海上风电导管架重要节点的三次焊接返修工艺

Research on three times welding repair technology of important joints for offshore windfarm jacket

针对海上风电导管架项目建设中壁厚≥50 mm的重要焊接节点存在施工要求高、返修难度大的问题,文中开发了这类重要节点的全位置(包括1G,2G和3G)3次焊接返修工艺方案:FCAW-G+FCAW-G+SMAW;返修坡口宽深比W/D≥0.9,根部圆弧半径R≥5 mm,坡口角度50°;并给出了返修中每道次的顺序及主要焊接工艺参数。对经历4次焊接热循环后的焊接接头的宏观形貌观察和力学性能测试结果表明:焊道宏观形貌良好,拉伸、弯曲、-40℃低温冲击吸收功、硬度均能满足相关标准和项目规格书的要求。由此可见,文中所开发的3次焊接返修工艺方案可推广应用于海上风电导管架等相关工程的施工,能够有效避免浪费施工材料,缩短建造工期,降低建造成本。

In view of the problems of high construction requirements and difficult repair of important welded joints with wall thickness larger than 50 mm in the construction of an offshore windfarm jacket project,a three time welding repair process scheme for all positions(including 1G,2G and 3G)of those important welded joints was developed.FCAW-G process was used for the first repair,FCAW-G process was used for the second repair,and SMAW was used for the third repair.Width-depth ratio of the repaired groove was greater than 0.9,the radiusRof the root arc was larger than 5 mm,and the groove angle was 50°.The sequence of each pass in the repair and the main welding parameters were given in this paper.The research results of the welded joint that had undergone four welding thermal cycles showed that the macroscopic shape of the weld bead was good,and the tensile,bending,low-temperature impact energy at-40℃and hardness could meet the requirements of relevant standards and project specifications.Therefore,three times repairing technology developed in this paper could be applied to the construction of offshore windfarm jacket and other related projects,which was beneficial to saving construction materials,shortening the construction period and reducing the cost.