某电厂再热系统缺陷原因及影响的分析

Analysis of Causes and Effects of Reheat System Defects in a Power Plant

为确保锅炉安全运行,基于某电厂锅炉再热系统运行现状,简述了再热系统的组成及工作原理,依托宏观检查、无损检测、金相检验等手段,分析了再热系统缺陷产生原因及影响,为日常运行和检验提供依据。结果表明:再热系统缺陷产生的普遍原因包括焊接缺陷以及运行过程中再热汽温调节方式不当两方面;再热系统内缺陷的产生沿再热蒸汽流程系统呈发展态势;再热汽温调节应以烟气挡板调节为主,喷水减温调节为辅,且应在停炉检修期间,对集箱管座角焊缝、管道三通以及喷水减温器重点关注,提出了制造安装、运行及检验中的一些建议。

To ensure the safe operation of boiler,based on the operation status of boiler reheat system in a power plant,the composition and working principle of reheat system are described,relying on macro examination,non-destructive examination,metallographic examination and other means,the causes and effects of reheat system defects are analyzed,provide basis for daily operation and inspection.The results show that:the common causes of reheat system defects include welding defects and improper reheat steam temperature regulation during operation;the defects in reheat system develop along the reheat steam process;reheat steam temperature regulation should be based on flue gas damper regulation,supplemented by spray desuperheating regulation.In addition,it is necessary to focus on of the fillet weld of header pipe seat,pipe tee and spray desuperheater during the shutdown maintenance.Some suggestions on manufacture,installation,operation and inspection are put forward.