自愈光学电流互感器现场运行稳定性试验

Investigation on Corrosion Behaviors of Anti-Corrosion

从互感器误差校验、电能计量统计和电能计量系统整体校验3个方面对光学电流互感器的现场运行性能进行客观评价。投运前和运行中期的误差校验数据显示,变差小于0.1%,满足0.2S级要求。建立2套独立计量系统,在实际现场运行条件下进行长期数据比对,反映数字电能计量系统在各种环境因素影响下的长期运行稳定性。通过对数字电能计量系统的整体校验,在额定功率条件下不确定度达到9.0×10-5,置信概率达到97.15%,系统综合误差为1.013%,满足规程要求。

In order to study the corrosion behaviors and the effects of compositions, inclusions and microstructures on corrosion resistance of joints, new type anti-corrosion E36 steels were welded by the anti-corrosion solid wires. The results show that the mechanical properties of joints are good enough to satisfy the standards of international association of classification societies. The microstructures of base metal dominantly consists of pearlite and banded ferrite, and heat affect zone of bainite, and weld metal of acicular ferrite, bainite and lath ferrite. There are no dis- continuous surfaces （e. g. , steps） between the base metal and weld metal. However, the corrosion resistance of weld metal is better than that of base metal and heat affect zone, and the corrosion resistance of heat affect zone is the worst. Besides, inclusions serve as the pitting initiation in weld metal.