运用有限元法对不同介质的管道采用不同工艺进行在线焊接时的温度场进行了数值模拟,内部介质流动对在线焊接温度场的影响通过介质与管壁的换热系数来体现,考虑随温度变化的材料性能。结果表明,在线焊接时的背温随着热输入的增大而升高。介质流动会带走焊接时产生的热量,不同介质带走的热量不同。水带走热量的能力较强,介质为气体时,由于换热系数较小,背温与常规焊接时相差不大。 The finite element method (FEM) was used to simulate the temperature field of pipeline with different media during on-line welding. The effect of internal flow on the temperature field of on-line welding was reflected by the heat transfer coefficient between the medium and the pipe wall, The material properties. The results show that the on-line welding temperature increases with the increase of heat input. Medium flow will take away the heat generated when welding, different media to take away the heat. The ability of water to take away the heat is strong, the medium is gas, due to the smaller heat transfer coefficient, back-up temperature and conventional welding or less.