余热发电锅炉低温过热器连接弯头开裂及处理对策

Cracking of Connection Elbow of Low Temperature Superheater in Congeneration Boiler and Treatment Countermeasures

某余热发电锅炉在经过一段时间运行后,在低温过热器连接位置弯头处发生了开裂问题。通过试验分析可知,开裂主要原因是锅炉安装后的煮炉过程中有碱液进入过热器,使得连接弯头在焊接位置产生了脆性开裂。对此提出了防止开裂的具体对策:利用超声波、射线检测等方式确定发生裂纹的位置,对存在裂纹的管段进行及时换新,防止锅炉运行时裂纹的进一步扩散,避免造成整个管道的停运,对于确保锅炉正常运行具有现实意义。

After the operation of cogeneration boiler for some time,cracking occurs in the elbow of the connection of low temperature overheater.The experimental analysis show that the main causes of cracking is the lye entering into overheater during boiling out after the boiler installation,causing the brittleness of connecting bend in welding position.The specific countermeasures for preventing cracking are proposed,i.e.to determine the location of cracks through ultrasonic and radiographic inspection,etc,renew the cracking tabulation in time,prevent the diffusion of the cracks during boiler operation,and avoid the offstream of the whole pipeline.This has practical significance for the normal operation of the boiler.