X80钢管双连管埋弧环焊用烧结焊剂研制

为了提高X80管线钢管双连管焊缝韧性和焊接工艺性，针对X80管线钢管双连管埋弧环焊工艺，对埋弧焊焊剂进行了优化。以CaF2-MgO-Al2O3-CaO-SiO2渣系为基础，加入稀土硅铁及镍合金等，研制出了一种适合于X80双连管埋弧环焊用烧结焊剂，并按照CDP-G-OGP-OP-081.01—2019-2《油气管道工程焊接技术规定 第1部分》标准进行了X80钢级双连管环焊试焊及焊缝性能检测。结果表明:采用所研制的焊剂配合相应焊丝焊接所得的环焊缝各项性能均能满足管道线路焊接标准要求，且环焊缝具备了良好的强韧性及断裂韧性，焊缝抗拉强度达到690 MPa以上，-10 ℃下焊缝冲击韧性达150 J以上，-10 ℃下焊缝CTOD值超过0.254 mm。

Development of Agglomerated Flux for Submerged Arc Girth Welding of X80 Steel Pipe

In order to improve the weld toughness and welding process of X80 pipeline steel pipe double jointing pipe，the submerged arc welding flux was optimized according to the submerged arc girth welding process of X80 pipeline steel pipe double jointing pipe.Based on CaF2-MgO-Al2O3-CaO-SiO2 slag system，the agglomerated flux suitable for submerged arc girth welding of X80 double jointing pipe was developed by adding the rare earth ferrosilicon and nickel alloy.According to CDP-G-OGP-OP-081.01—2019-2 technical regulations for welding pipeline，X80 double jointing pipe butt joint trial welding and weld performance inspection were carried out.The results show that the properties of the girth weld obtained by using the developed flux and corresponding welding wire can meet the requirements of pipeline technical regulations，and the girth weld has good strength，toughness and fracture toughness.Among them，tensile strength of the weld is more than 690 MPa，the impact toughness of the weld at-10 ℃is more than 150 J，and the CTODat-10 ℃is more than 0.254 mm.