P9管道背面免充氩焊丝的应用技术

Application technology of back argon free welding wire for P9 pipeline

某炼厂延迟焦化装置4台加热炉炉管需更换,炉管材质为ASTM A335 P9,该材料焊接以往所采用的充氩焊丝,需采用必要的工装进行充氩保护焊接,但因保护困难,焊接合格率不高,因此确定采用TGF90S-G免充氩焊丝进行焊接。开展了免充氩焊丝的焊接工艺性试验,研究了免充氩焊丝在焊接过程中的背部成形、背部脱渣和焊接一次合格率,分析各焊接工艺参数、技术措施对焊缝成形及性能的影响,制定了最优化的焊接技术方案,最终形成了合格的焊接工艺评定,并成功应用于该项目加热炉炉管的焊接,高效优质地完成了该装置加热炉炉管的更换工作。

In the furnace tube replacement of 4 heating furnaces in a delayed coking unit of a refinery,the material of furnace tubes is ASTM A335 P9.The argon-filled welding wire used in the past should be welded with the necessary tooling.However,due to difficult protection and low welding qualification rate,TGF90s-g argon free welding wire is determined to be employed for welding.This paper conducts a welding process test of the argon free welding wire and studies the back forming,back deslagging,and the one-time qualified rate of the argon free welding wire in the welding process.The effects of various welding process parameters and technical measures on the weld forming and performance are analyzed and the optimized welding technology scheme is formulated.Finally,the qualified welding process evaluation is formed and successfully applied to the welding of the heating furnace tube of the project.The furnace tube replacement of the heating furnace of the device has been completed with high efficiency and quality.