直缝埋弧焊钢管焊缝点状缺陷原因分析及改进

为了解决壁厚23 mm直缝埋弧焊管出现的焊缝点状缺陷问题，通过超声波探伤和宏观金相检测对实际生产过程中出现的焊缝点状缺陷不合格试样进行了分析，对铣边坡口形状、焊接工艺参数、焊接材料、焊接设备及焊件清理等方面给出了相应的优化改进措施。现场应用效果表明:这些措施的实施有效控制了此类直缝埋弧焊管焊缝中的点状缺陷，保证了直缝埋弧焊管焊缝形貌及各项力学性能指标，提高了焊接质量。

Cause Analysis and Improvement of the Weld Spot Defect in Longitudinal Submerged Arc Welded Steel Pipe

In order to solve the problem of the weld spot defects in longitudinal submerged arc welded pipe with a wall thickness of 23 mm, the paper analyzes the unqualified sample of the weld spot defects in the actual production process through the ultrasonic flaw detection and the macro metallographic, and gives the corresponding optimization and improvement the measures in the aspects of milling groove shape, welding process parameters, welding materials, welding equipment and weldment cleaning. The field application results show that the implementation of these measures effectively controls the spot defects in the weld of the longitudinal submerged arc welded pipe with a wall thickness of 23 mm, ensures the weld morphology and various mechanical performance indexes of the longitudinal submerged arc welded pipe, and improves the welding quality.