SA335P91管道与12Cr1MoV蒸汽取样器异种钢的焊接及热处理

Dissimilar Steel Welding and Heat Treatment of SA335P91 Pipe and 12Cr1MoV Steam Sampler

为解决某火电厂5~#机组施工完毕的主蒸汽管道上漏项设计蒸汽取样器的问题,根据现场实际情况,在主蒸汽管道上补装。通过分析厚壁大径主蒸汽管道(SA335P91)与小径蒸汽取样器(12Cr1MoV)的异种钢焊接工艺特点,制定了焊接、热处理工艺方案。经过严格控制焊接线能量和热处理预热、层间温度及焊后热处理工艺过程,获得优良的焊接接头,焊后进行外观目测、无损检测、硬度检测,符合要求。机组已安全运行约55 000 h,验证了该焊接与热处理工艺是正确的。

In order to solve the problem that the main steam pipe of 5~# unit in a power plant completed construction on the design missing items steam sampler device,according to the actual situation,fill installation was completed in the main steam pipeline. Through the analysis of large diameter thick wall of main steam pipe（ SA335P91） and small diameter steam path sample（ 12Cr1MoV） characteristics of welding process of dissimilar steel,welding and heat treatment process program was made.Through strict control of welding line energy and heat treatment preheating,inlayer temperature and heat treatment after welding process,good welding joints are obtained. Welding appearance,nondestructive testing,hardness testing were proceeded after welding,which meet the requirement. The unit has been running safely for about 55 000 h,verifying that the welding and heat treatment process is correct.