中俄东线用大壁厚螺旋埋弧焊管预精焊工艺研究

摘要

为了保证中俄东线天然气管道的正常生产,采用预精焊工艺试制了X80钢级Φ1422 mm×21.4 mm大壁厚螺旋埋弧焊管,并对其焊缝力学性能、 冲击韧性、 显微硬度、 化学成分和微观组织特征进行了分析.结果表明,预焊焊缝微观组织为板条马氏体,精焊内、 外焊缝微观组织为针状铁素体+少量珠光体,焊缝边缘整齐美观,脱渣良好,能够消除内焊"马鞍形"焊缝.试验结果表明,试制的螺旋埋弧焊管各项性能指标完全满足中俄东线大壁厚天然气管道的生产技术条件,为X80钢级Φ1422 mm×21.4 mm大壁厚螺旋埋弧焊管的生产提供参考.%In order to ensure normal production of Russia-China eastern route natural gas pipeline,X80 grade Φ1422 mm× 21.4 mm thick wall SAWH pipe was trial-produced by two-step welding process,and the mechanical property,impact toughness,microhardness, chemical composition and microstructure of weld were analyzed. The results showed that,the microstructure of prewelding weld was lath martensite,the microstructure of inside and outside weld were acicular ferrite and a little pearlite,the weld edge was smooth with good slag detachability,and the saddle-shape weld was eliminated. According to the results the performance index of trial-produced SAWH pipe could completely meet the production specifications of Russia-China eastern route thick wall natural gas pipeline,which could provide the reference for X80 grade Φ1422 mm × 21.4 mm thick wall SAWH pipe production.