X80M钢Φ1219 mm×18.4 mm螺旋埋弧焊管导向弯曲不合格原因分析

Analysis of Unqualified Guide Bending Test of X80M Φ1 219 mm×18.4 mm SSAW Pipe

针对X80M钢Φ1 219 mm×18.4 mm螺旋埋弧焊管生产中出现的导向弯曲试验不合格现象,通过钢管性能分析、热模拟试验分析、焊接参数分析及微观组织分析等手段,对出现导向弯曲不合格的原因进行了系统、全面的分析,得出了以下结论:厚壁螺旋埋弧焊管生产时易出现热影响区软化;厚壁螺旋埋弧焊管卷板订货时强度不宜过高;螺旋埋弧焊管卷板板边的夹杂物缺陷在弯曲应力作用下,易形成脆性断裂区,最终导致开裂。通过控制焊接热输入、合理制定卷板强度范围、调整板边铣削量等手段可避免此类缺陷的产生。

According to unqualified guide bending test of X80M Ф1219mm×18.4mm SSAW pipe in production, property , thermal simulation, welding parameters and microstructure were analyzed for unqualified reasons. The results showed that softening of heat-affected zone was more likely to occur on heavy-wall SSAW pipe production; parent metal strength of wiled sheet should not be too high; because of inclusions on the edges of wiled sheet with bending stress, brittle fracture zone was easily formed and finally leaded to crack. The above methods could prevent the defect, including controlling heat input of wehting, setting reasonable strength range and adjusting edge milling parameters.