X70M大壁厚螺旋埋弧焊管丁字焊缝工艺性能研究

X70M大壁厚螺旋埋弧焊管丁字焊缝焊接接头强度过高，经过成型器反变形易产生层状撕裂，焊缝热影响区温度过高易使焊缝组织产生脆化现象，为了确保X70M大壁厚螺旋埋弧焊管丁字焊缝焊接接头的各项性能指标，采用H08D焊丝与SJ101G焊剂匹配进行工艺试验，焊接过程中严格控制层间温度、减小焊接热输入及焊后热处理形式，通过试验得出了合理的焊接工艺。试验结果表明，按该工艺所焊试件的各项性能指标均达到API SPEC 5L PSL2标准及客户技术条件，采用此工艺已成功地生产了数万吨尼日利亚输油管线用管，效果良好。

Investigation on the Technological Properties of X70M Thick Wall SAWH Pipe T-shape Weld

If the welded joint strength of X70M thick wall SAWH pipe is too high, it is easy to generate backward deformation and lamellar tearing when pass through the forming machine, embrittlement phenomenon easily happen caused by too high HAZ temperature. In order to ensure the performance index of X70M thick wall SAWH pipe T-shape weld welded joints, using H08D welding wire matching with SJ101G flux to carry out process test, during the welding process strictly controlled interpass temperature, reduced the welding heat input and the form of heat treatment after welding, the reasonable welding process was obtained through experiments. The test result showed that all performance indexes of specimen by adopting the above process reach the standard API SPEC 5L PSL2 and customer technical conditions, it successfully produced tens of thousands of oil pipeline in Nigeria by adopting this technology, and the effect is good.