亚临界机组蒸汽冷却间隔管爆管分析  

Analysis of Steam Cooling Interval Tube Explosion in Subcritical Unit

作　　者：梁瀚钊 李勇军 陈超 傅其东 Liang Hanzhao;Li Yongjun;Chen Chao;Fu Qidong(Guangxi Special Equipment Inspection and Research Institute,Nanning 530200;Datang Guiguan Heshan Electric Power Co.,Ltd.,Laibin 546501)

机构地区：[1]广西壮族自治区特种设备检验研究院,南宁530200 [2]大唐桂冠合山发电有限公司,来宾546501

出　　处：《中国特种设备安全》2021年第4期114-117,共4页China Special Equipment Safety

摘　　要：利用宏观检测、光谱成分分析、金相组织分析、显微硬度分析,对某电厂亚临界锅炉蒸汽冷却间隔管爆管原因进行分析.结果表明:爆口侧材质为20G,金相组织已严重老化,珠光体球化级别达到了4.5级,珠光体区域中的碳化物已经明显分散,同时,该处的显微硬度值接近正常硬度值区间的下限.根本原因是未按照有关国家标准和行业标准的要求选用锅炉使用的受压元件材料,蒸汽冷却间隔管的管壁平均温度超过460℃,20G的许用壁温不得超过460℃.By means of macroscopic examination,spectral composition analysis,metallographic structure analysis and microhardness analysis,the failure causes of steam cooling interval tube explosion in a subcritical boiler of a power plant were studied.The results show that the material of the crater side is 20G,the metallographic structure has been seriously aged,the pearlite spheroidization level has reached 4.5,the carbides in the pearlite area have been obviously dispersed,and the microhardness value in this area is close to the lower limit of the normal hardness value range.The root cause is that the pressure element materials used in the boiler are not selected according to the requirements of relevant national standards and industry standards.The average wall temperature of steam cooling interval tube shall be more than 460°C,and the allowable wall temperature of 20G shall not exceed 460°C.

关 键 词：亚临界锅炉 20G 15CrMoG 金相组织 显微硬度 

分 类 号：X933.2[环境科学与工程—安全科学]