From: Failure analysis of weld cracking of gas gathering pipeline in dewatering station
Item
Weld microstructure
Fusion zone
Fine grain zone
Invalid girth weld
Filling layer: IAF+GB+PF+P (Fig. 10)
Root welding: PF+P (Fig. 11)
GB+PF+P (Fig. 12)
PF+P (Fig. 13)