通过在某台超超临界参数锅炉水冷壁管特定区域安装能同时测试水冷壁管向火侧壁温、背火侧壁温及管内工质温度的测试装置，实现对水冷壁管温度的实时监测，分析不同工况下投运炉膛吹灰器对水冷壁壁温的影响。结果表明：变负荷工况下燃烧强度与给水流量的不匹配特性易导致水冷壁超温，该工况下的吹灰会加剧壁温突升的幅度，且连续升负荷工况下壁温突升，约至80 ℃；相同试验时间内，最大壁温突升幅度和平均壁温突升幅度都随着吹灰汽源压力的降低而升高，吹灰汽源压力1.2 MPa时，最大壁温突升幅度约74 ℃；单只吹灰器每天投运两次使得当天壁温突升频次达到约15次，最高壁温约达到75 ℃，壁温突升频次和幅度较每天投运一次明显上升；稳定高负荷工况下吹灰对水冷壁壁温的影响最小。推荐炉膛吹灰操作尽量选择在稳定高负荷工况进行，同时保证吹灰汽源压力高于1.2 MPa，并尽量减少一天内单只吹灰器的投运次数。

Some testing devices,which could test the fire side tube temperature,the back side tube temperature and the working medium temperature,were installed in some specific water wall tubes in an ultrasupercritical boiler.The tubes and working medium temperatures were online monitored and the influences on water wall temperature of furnace soot blowing under various operating conditions were analyzed.Studies show that the mismatched characteristic of combustion intensity and feed water flow under the variable load conditions can lead to the water wall overtemperature.Soot blowing under these conditions will aggravate the tube temperature increment and a sudden rise of about 80 ℃ may occur especially under continuous load lifting condition.The maximum and average tube temperature increments increase with the decrease of sootblowing steam source pressure in the same test time.The maximum tube temperature increment can reach about 74 ℃ when the sootblowing steam source pressure is 1.2 MPa.The frequency and maximum range of temperature rise can reach 15 times and about 75 ℃,respectively,when a single sootblower is working twice a day,significantly higher than the sootblower working once a day.Soot blowing under stable and high load condition generates minimum effect on the water wall tube temperature.Therefore,it is recommended to conduct sootblowing in furnace under stable and high load condition as much as possible with the steam source pressure higher than 1.2 MPa,and the operation times of a single sootblower should be minimized in a day.

TK223.3