甲醇装置预转化炉安全阀引出支管TP304H材料焊缝裂纹原因分析及处理方法

THE ANALYSIS OF WELDING CRACK ON BRANCH PIPE WITH MATERIAL TP304H AND TREATMENT METHOD

甲醇装置预转化炉入口气管与安全阀引出支管TP304H焊缝材质和母材热影响交界区域出现裂纹,造成介质泄漏,导致装置非正常停车。通过对现场实际裂纹形式、裂纹部位、走向、长度、深度进行检测,并结合裂纹状态及金相组织分析结果,综合进行分析,找出裂纹产生的原因,并制定出合理有效的焊接工艺及方法,成功解决TP304H奥氏体耐热不锈钢管道裂纹问题,保证了生产装置的安、稳、长、优运行。

In a methanol plant,the pre-reformer outlet gas pipe and the branch pipe leading out from the safety valve,both with welding material TP304H,were welded on base metal.However the crack occurred in heat impacted border area,leading to medium leakage and abnormal shutdown of the plant.Studying on site the real crack form,crack location,its direction,length and depth,combined with the analyzing results of crack model and metallographic structure,we found the reason of crack generation,and established an effective welding process and method,therefore successfully solved the problem of TP304H heat resistant stainless steel pipe crack,which guaranteed the plant operation to be safe,stable and to run in a long cycle life.