某电厂高温再热蒸汽管道下沉原因分析及治理

针对某电厂高温再热蒸汽管道异常下沉的情况,本文通过对该管道的冷态和热态全面检查、应力校核、壁厚测量及部分恒力吊架的恒定度测试,找出了导致管道下沉的三个主要原因,分别是支吊架选型荷载偏小、弯头壁厚比设计壁厚偏大、恒力吊架恒定度不满足标准要求。通过更换两组恒力吊架和新增一组恒力吊架,高温再热蒸汽管道下沉现象得到明显改善,支吊架冷、热态正常,消除了机组安全运行的隐患。

Cause Analysis and Treatment for Sinking of High Temperature Reheat Steam Pipeline in a Power Plant

Aiming at the abnormal sinking of high temperature reheated steam pipelines in a power plant,this paper finds out the causes of pipelines by comprehensively checking the cold and hot states of the pipeline,stress check,wall thickness measurement,and the test of some constant force hangers.Three main causes of pipe sinking are found out,namely,the selection load of supports and hangers is too small,the wall thickness of elbows is larger than the design wall thickness,and the constancy of constant hangers does not meet the standard requirements.By replacing two sets of constant-force hangers and adding a new set of constant-force hangers,the sinking phenomenon of high-temperature reheat steam pipes has been significantly improved,and the cold and hot states of the support hangers are normal,eliminating the hidden dangers of safe operation of the unit.