现阶段1 000 MW机组锅炉，低负荷下的管壁超温问题越来越突出，在深度调峰背景下，为解决其低负荷稳燃时的管壁超温问题进行了试验研究，比较燃烧器拉杆和磨煤机组合方式对屏式过热器、高温过热器和高温再热器管壁温度的影响，摸索出了低负荷运行时屏式过热器控制超温的思路，即低负荷运行时，采取关小两侧燃烧器区域风门开度、开大中间燃烧器区域风门开度的调整方法对燃烧器区域拉杆进行调整。优化调整后，500 MW负荷、AEF磨煤机组合运行方式下，屏式过热器管壁最高点温度由616.3 ℃降低至600.5 ℃，大大提高了管材的安全裕量，保证了低负荷下机组的安全稳定运行。

At the present stage of 1 000 MW boiler,the overtemperature problem of tube wall under low load is becoming more and more prominent,especially under the condition of deep peak shaving.Then how to guarantee the stable combustion without overtemperature of the tube wall under low load is worth studying.This paper uses the No.2 boiler of a power plant as the research object.In view of the low load operation prone to superheater overtemperature problems,the effects of the burner rod and mill combination mode on the performance of the tube wall temperature of superheater,high temperature superheater and reheater are studied.It is found that for the overtemperature control for the plate superheater at low load operation,turning down the damper of side wall burner zone and opening the damper of the middle burner area can be used for the adjustment.Through optimization,at low load of 500 MW,and AEF grinding operation,the maximum wall temperature decreases from 616.3 ℃ to 600.5 ℃,greatly improving the safety margin of the pipe and ensuring the safe and stable operation of the unit at low load.The results can provide a reference for the optimization and adjustment of tube wall temperature for the same type of unit.

TK229