某660 MW超超临界机组省煤器出口导管膨胀异常原因分析

Cause Analysis of Abnormal Expansion of Economizer Outlet Conduit in a 660 MW Ultra-supercritical Unit

火力发电厂汽水管道输送高温高压介质,其安全性是电站安全性的重要组成部分,近年来管道膨胀异常引发的事故较多,引起行业内关注。以某660 MW超超临界机组省煤器出口导管为例,针对该管道膨胀异常的情况,从现场勘察、支吊架性能测试、多工况管系应力分析等方面,对该管道膨胀异常原因进行了深入分析。结果表明,支吊架荷载偏大是管道膨胀异常的主要原因,建议暂不对恒吊荷载进行优化,但应对该管道的重点区域进行关注,对该管道的运维策略进行优化。

As steam water pipelines of thermal power plant transports high temperature and high-pressure medium,their safety is an important part of power plant safety.In recent years,there are many accidents caused by abnormal pipeline expansion,which has attracted the attention of the industry.Taking an economizer outlet conduit in a 660 MW ultra-supercritical unit as an example,an in-depth analysis of the causes of the abnormal expansion of the pipelines is carried out from the following aspects,such as field investigation,support and hanger performance test,and multi-condition piping stress analysis etc.The analysis results show that the main reason of abnormal expansion of pipelines is that the load of support and hanger is too large.And it is suggested to keep the constant load unchanged and pay attention to the key areas of the pipelines and also optimize the operation and maintenance strategy of the pipelines.