Numerical simulation of 80 ℃ temperature field distribution of thick plate multi-pass welding with SYSWELD

The PPG PITT-CHAR XP flame retardant system has been used by COOEC to preventing the thermal softening of steel in the high temperature，whose degradation temperature is 80 ℃. To prevent damage to PPG PITT-CHAR XP fire retardant paint from excessive heat during welding, it is necessary to get accurately reserved area near the welding joints prior to welding. For the foregoing reasons, the 80 ℃ temperature field distribution of thick plate multi-pass welding was analyzed with SYSWELD. The influence of welding groove form and time interval on welding temperature field was also analyzed. Results showed that the range of 80 ℃ welding temperature field increased with the increasing of weld layers at first and then it inclined to stable value. Interpass time setting was crucial to control the range of 80 ℃ welding temperature field. It was also found that double V groove had better thermal diffusivity than double-bevel groove. And double-bevel groove was better than single V groove.