预加氢反应器焊缝裂纹成因分析

Cause Analyses of the Weld Seam Cracks of a Prehydrogenating Reactor

无损检测发现预加氢反应器筒体环焊缝处存在多处埋藏裂纹。检测了反应器筒体基层(SA3 87Gr11C12 )和复层 (SA2 40TP3 2 1)材料的化学成分和力学性能 ;分析了反应器的热处理工艺参数和焊接工艺参数 ,计算了筒体材质的焊接裂纹敏感性指数 ;得出导致筒体焊缝开裂的主要因素是反应器高温回火保温时间不足、筒体材料的焊接裂纹敏感性指数较高、焊前预热温度偏低以及复合钢板过渡层焊接的复杂性。

Many buried cracks were founded out in the circle weld seam on the cylinder of a prehydrogenating reactor with non destructive inspection. In order to find out the crack causes, the chemical compounds and mechanical performance of the base layer (SA387Gr11C12) and the compound layer ( SA240TP321) materials were inspected, the heat treatment and weld process parameters of the reactor were analyzed, the sensitive indexes of the weld cracks of the reactor cylinder material were calculated, it was concluded that the major factors of the weld cracks of the cylinder were because of the lack of the high temperature temper insulation time, the high sensitive index of the weld cracks of the reactor cylinder, the low preheating temperature before welding and the weld complicacy of the intermediate layer of the compound steel sheets. Some heat treatment and weld process parameters were proposed for the reference of the same type apparatuses.