摘要
某发电公司为防止过热器氧化皮剥落引起过热器爆管事故,在机组检修期间,对其进行割管检查。在使用氩弧焊恢复过程中,为使焊缝处于氩气保护氛围,使用上海某科技公司生产的“速溶型水溶纸”对焊口两端进行了封堵。机组并网后主蒸汽氢电导率多次出现超标现象,经分析,主要原因是机组启动前没有对过热器进行充分的冲洗,该速溶型水溶纸氯化物和硫酸盐等含量过高,残存的水溶纸在机组启动后持续释放出氯化物和硫酸盐等杂质离子导致主蒸汽氢电导率出现异常偏高。对此提出了防范措施,以确保主蒸汽品质达标。
In order to prevent superheater tube burst caused by oxide coat peeling in a power generation company,pipe cutting inspection was carried out during unit overhaul.In the recovery process with argon arc welding,a special type of “instant water-soluble paper” was used to seal both ends of the weld in order to make the weld be protected by argon atmosphere.The hydrogen conductivity of the main steam of the unit repeatedly exceeded the standard after being connected to the grid.The main reason is that the superheater had not been washed sufficiently before the unit start-up.The content of chloride and sulfate in the instant water-soluble paper is too high.The residual water-soluble paper continuously releases impurity ions such as chloride and sulfate after the unit start-up.It is the main reason for the abnormal high hydrogen conductivity of main steam.Preventive measures are put forward to ensure that the quality of main steam reaches the standard.
作者
周志彬
常亮
ZHOU Zhibin;CHANG Liang(Rundian Energy Science and Technology Company Limited,Zhengzhou 450000,China)
出处
《华电技术》
CAS
2019年第7期67-69,共3页
HUADIAN TECHNOLOGY
关键词
水溶纸
氩弧焊
主蒸汽
氢电导率
极限摩尔电导率
羧甲基纤维素
water soluble paper
argon-arc welding
main steam
hydrogen conductivity
limiting molar conductivity
carboxymethyl cellulose