微量喷水减温器管道泄漏原因分析和处理

Analysis and Treatment on Pipeline Leakage of Spray Type Desuperheater

某电厂3号锅炉低温再热器至高温再热器的微量喷水减温器出口后管道后弯头焊缝出现开裂和泄漏现象,通过对微量喷水系统进行试验和计算,从再热蒸汽温度调节方式、管道焊接工艺等方面分析了泄漏原因,指出锅炉存在微量喷水减温器结构设计和再热蒸汽温度调节方式不合理、管道焊接工艺不佳等问题,提出相应的处理和预防措施,如增大微量喷水减温器混合段长度,以烟气挡板调节方式作为再热蒸汽温度的主要调节手段,打磨管道弯头焊口使之圆滑等。

There are crazes and leakage in welding lines in back-elbow of back-pipelines of spray type desuperheater outlet between low-temperature reheater and high-temperature reheater of No.3 boiler in a power plant.By testing and calculation on spray type desuperheater,reasons for leakage are analyzed in terms of adjusting means of reheat steam temperature,welding process of pipelines and so on.It is indicated that there are unreasonable structural design of spray type desuperheater,adjusting means of reheat temperature and poor welding process of pipelines.Some relevant countermeasures and precautions are brought forward,such as increasing the mixing section of spray type desuperheater,adopting adjusting means of gas baffle as main means of regulation for reheat steam temperature,burnishing the weld junction of pipe elbow in order for smoothness and otherwise.