Thermal simulation on coarse grained region of L415 pipelines in high sour gas field

摘要

corrosions on gathering and long-distance pipelines in high sour gas field are often found on the HAZ, coarse grained region is the weakest region in the HAZ. We got L415 Pipelines' coarse grained region of different heat inputs and post-treatments by welding thermal simulation, researched microstructures, hardness, impact energy and fracture, the result showed that, when the heat input is 25KJ/Cm, followed by annealing treatment with temperature 700°C for 1 hour, we can get good mechanical properties of coarse grained region.