390MW级燃气-蒸汽联合循环发电机组余热锅炉受热面泄漏检修方案研究

Research on Overhaul Scheme for Heat-surface Leakage of Heat Recovery Steam Generator in 390MW Class Gas-steam Combined Cycle Unit

针对390MW级联合循环发电机组余热锅炉受热面泄漏的问题,首先从其结构特点和设计制造工艺方面进行了分析,然后对其检修方案进行深入研究,自主引入了轻型脚手架结构与搭设技术,确立了技术规范,节约了时间,提高了安全性;结合燃煤电厂经验与9F级联合循环机组自身的特点,创造逐步接近法来判定漏点的方法;深入探讨剥离鳍片、割断管子的工具及工艺,提出并比较了各种可选择的漏点检修方案,制定出若干通用检修工艺;对特殊情况下的管束、管屏批量更换,列出了逆安装工序法、单根拼装法、成排拼装法等数种处理方案,比较了优劣点,对较实用的单根拼装法编制了详细的检修方法、工序与工艺;对保温拆除与恢复进行了方案性探讨;该原创性研究取得了良好的实用价值。

In view of the heat-surface leakage of heat recovery steam generator（HRSG） in 390 MW class gas-steam combined cycle unit,the structural features as well as the design and fabrication technique thereof are analyzed first;then the overhaul scheme is deeply investigated.Lightweight scaffold and staging techniques are introduced independently to save time and improve safety.Combined with the experience of coal-fired power plant and the features of 9F class combined cycle unit,the cut-and-trial way is created to find leaks.The tools and arts to peel off the pins and cut the tubes are thoroughly explored.Optional leakage overhaul schemes are proposed and compared,several general maintenance techniques worked out.For batch replacement of tube banks and panels under specific conditions,several methods including inverse installation procedure,single-tube assembling and bank assembling are listed and compared.Detailed maintenance procedures are formulated for the practical single-tube assembling method.The heat preservation removing and restoring plans are discussed.The research is of favorable practical value.