使用高铬镍奥氏体焊材无热处理焊接ASTM A335 Gr.P22管材

Utilizing welding consumable of high Cr and Ni contents to weld ASTM A335 Gr.P22 pipe without needing heat treatment

ASTM A335 Gr.P22材料焊接性较差,由于受到现场施工条件及焊缝位置等的限制,该类母材部分焊缝不便于进行局部热处理,为此采用了高铬镍焊材,不预热、后热及焊后热处理的焊接工艺进行焊接。试样的力学性能试验及金相分析表明,力学性能符合要求,金相组织良好,焊接工艺满足NB/T 47017-2011规定要求;该焊接工艺用于国内某炼厂ASTM A335Gr.P22孔板法兰与引压短管角焊缝的焊接工程实践表明,装置自2014年投产运行至今采用该工艺施焊的所有焊缝均正常。

ASTM A335Gr.P22is a kind of material of poor weldability.Preheat and PWHT are not applicable in site welding of ASTM A335Gr.P22due to limitations of site condition and weld position.To solve the problem,the welding process of using welding consumable of high Cr and Ni contents,no preheat,no heating and no PWHT is adopted.The welding process is in line with NB/T470172011,the mechanical performance and metallographic microstructure of the test coupon are qualified by lab testing.The welding process has been utilized for the fillet welds of ASTM A335Gr.P22orifice flange and impulse tube in a domestic refinery.The unit has been put into production since2014till now,all the welds by applying this welding process are in good condition.