大壁厚螺旋埋弧焊管补焊工艺研究

摘要

为了研究大壁厚螺旋埋弧焊管多次补焊后焊缝性能的变化情况，利用夏比冲击试验、拉伸试验、弯曲试验、硬度检测和金相检验等方法对壁厚为21.4 mm的螺旋埋弧焊管不同补焊工艺完成的焊接接头进行了检验。结果发现，5种不同补焊工艺下焊接接头的拉伸性能、冲击韧性、弯曲性能及硬度值均满足标准要求，与原始焊接接头相比，补焊后的试样焊接接头微观组织未发现严重的晶粒长大现象，且未出现其他脆性组织，经理化检验和无损检测，3次至5次补焊性能也均能满足西气东输管线标准要求，为多道次的补焊工艺推广打下坚实的理论基础。%In order to study the weld performance change of heavy wall thickness SAWH pipe after many times repair welding, the different repair welding process for 21.4 mm heavy wall thickness SAWH pipe welded joint was tested by means of Charpy impact,tensile test, bending test, hardness testing and metallographic test. The result indicated that the tensile property of welded joint, impact toughness, bending property and hardness value all meet the requirements of the standard. Compared with the original welded joints, no serious grain growth phenomenon of welded joints after repair welding was found, as well as other brittle structure. After 3~5 times repair welding,the performance of both physical and chemical inspection and nondestructive testing can meet the standard requirements of the West-to-East Gas Pipeline Project. And it can lay a solid theoretical foundation for the multi-pass repair welding technology.