对球罐的检验、缺陷处理与防腐

Inspection,defect treatment and anti-corrosion of spherical tanks

采用宏观检查和MT,UT,RT等无损检测的方法,对多台、多种材质的球罐进行全面检验,以此发现球罐中存在的隐患。对大多数缺陷,采用打磨清除、焊接修补的方法彻底处理干净,并给出了焊接修补的技术要点和工艺参数;对少数遗留的缺陷,依据断裂力学理论用两种不同的计算方法作出安全评定;在使用维护中,对球罐外壁涂刷适当的涂料进行防腐保护,限定介质中的H2S含量来防范内壁应力腐蚀破坏。实践证明,检验是有效的,缺陷处理所采用的方法是可行的、也是可靠的,保证了球罐的安全运行。

A number of spherical storage tanks of different metallurgies were inspected with non-destructive testing methods, i.e. macro testing, MT, UT and RT, etc to find out the potential safety hazard. Most of the defects were repaired by blasting and welding, and the technical requirements and process parameters of repair welding were described. For the remaining defects, safety assessment was performed using two different calculation methods based upon fracture mechanics. In operation, an appropriate coating was applied on the external wall of the tanks for corrosion protection, and H2S in storage media was controlled to prevent SSCC of internal wall. The practices show that the inspection is effective and the defect treatments are practical and reliable, which have ensured the safe operation of spherical tanks.