超临界汽轮机高中压缸大体量缺陷的焊接修复

Welding Repair Methods of Large Volume Defects in High-Medium Cylinder of Supercritical Steam Turbine

针对超临界机组汽轮机汽缸在生产加工过程中发现的大体量缺陷,根据两个焊接修复案例,研究探讨了采用异质钢冷补焊(不属于冷焊,使用的不是异质钢焊材,是镍基合金焊条)在汽缸修复中的可行性及安全性。研究表明,采用镍基合金焊条,小规范参数电弧冷焊,层间锤击消应力,必要时焊后进行消氢处理,对于超临界机组Cr Mo钢和马氏体耐热钢汽轮机缸体铸件的大体量缺陷修复是可行及安全可靠的。

For large volume defects found in the manufacturing process of cylinder of supercritical steam turbine,according to two welding repair cases, the feasibility and safety of the cylinder repair using nickel-based welding rod were studied. The results show that using nickel based alloy electrode, SMAW with small specification parameters, and interlayer hammer to eliminate stress, dehydrogenation heat treatment after welding if necessary, it is feasible, safety and reliable for the repair of large defects in Cr Mo steel and martensitic heat resistant steel cylinder casting used in supercritical turbine.