三元流叶轮焊接裂纹分析及工艺改进

Welding Crack Analysis and Process Improvement of the 3-D Flow Impeller

对某三元流叶轮焊接后出现裂纹的原因进行了分析,认为其主要是因为结构刚度相对较大产生的冷裂纹。对此,从改善叶轮焊接前的材料组织状态、降低叶轮的拘束应力和优化叶轮焊接生产的工艺流程入手,提出了对应的改进措施,确保了叶轮的焊接质量,特别是改造后的焊接叶轮经过整体调质热处理后,母材和焊接的组织更为均匀。

The reasons of welding cracks of the 3-D flow impeller were analyzed in this paper,it was considered that welding cold cracks was mainly caused by the relatively large structure stiffness of the impeller.Then the improvement should be from the aspects of improving materials organization before the impeller welding,reducing confining stress of impeller,and optimizing welding production technological process of impeller.The corresponding improvement measures were proposed and the welding quality of impeller was assured.Especially through the heat treatment process for the impeller after transformation,the organization of base metal and weld were more evenly.