通过对270篇电厂锅炉水冷壁爆管事故类文献研读，归纳得出造成爆管的直接原因是超温和化学腐蚀分别占21.27%、18.73%，作为根本原因之一的燃料粒度不均以及燃烧方式不当占14.44%，器壁结垢堵塞作为水冷壁管泄漏的一个间接原因占10.79%，这几种因素合计引起的泄漏次数在总泄漏次数中占65.23%，为水冷壁发生泄漏时应该优先考虑的因素。按水冷壁发生化学腐蚀的位置进行统计，得出水侧和火侧的化学腐蚀分别占64.41%和35.59%。将水冷壁水侧的化学腐蚀因素进一步分类得到氢腐蚀占36.84%，碱腐蚀占21.05%，酸腐蚀占15.79%以及蒸汽腐蚀占11.84%。这4种化学腐蚀因素合计引起的爆漏次数占所有水侧化学腐蚀因素引起爆漏次数的85.52%，为化学腐蚀因素中应该优先考虑的因素。另外，还分别讨论了不同功率机组的水冷壁腐蚀失效情况。以上结论对现有电厂水冷壁泄漏原因的快速查找和预防起到一定作用，在维持设备长期经济安全运行方面具有一定的实际意义。%This paper is based on the literature survey,after collecting the power plants’ water wall tube burst accident data,and making research on the 270 pieces of literature on boiler water wall tube explosion accident,it comes to the conclusion that the direct reasons for the tube explosion of boiler water wall in power plant are overheating and chemical corrosion which accounted for 21.27% and 18.73%,respectively. The improper boiling way and uneven grain size of burning fuel which serves as the primary causes accounted for 14.44% and the deposition jams on the wall which is one of the indirect causes accounted for 10.79%. The summation of these main reasons can make up for 65.23% in the total number of explosive leakage. When boiler water wall tube leakage happened,the above reasons were the first to be considered. Also,the material quality and abrasion are the explosion factors. Chemical corrosion is divided into fire side and water side by the occurred places,which account for 35.59% and 64.41%,respectively. The factors of the water side chemical corrosion can be classified into hydrogen corrosion accounted for 36.84%,alkali corrosion accounted for 21.05%,acid corrosion accounted for 15.79% and steam corrosion accounted for 11.84%,respectively. The summation of the four kinds of corrosion types can make up to 85.52% in the total number of corrosion factors. These are priorities in the factors that should be considered. In addition,it discusses the water wall failure of different units. The above conclusions have some certain effect on the finding of water wall leakage reasons in the existing plants,and these have a certain practical significance to ensure long-time stable, safe and economic operation of boilers.
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