基于新型无损检测仪的奥氏体锅炉管内壁氧化皮堵塞爆管探析.doc

基于新型无损检测仪的奥氏体锅炉管 内壁氧化皮堵塞爆管探析 彭欣 李友庆 曾劲松 王双勇 任建文 湘潭发电有限责任公司 摘 要： 奥氏体不锈钢氧化膜脱落堵塞引起爆管的问题已严重威胁火电厂的运行，作者通过分析湘潭电厂采用传统的射线拍片检查和自主研发新型专用无损检测仪对管子进行检测的情况，突出新型专用检测仪具有检测准确快捷、灵敏度高、对被检测管子无要求的优点。并根据两台超临界锅炉的检测结果分析了氧化皮堵塞的特点，同时结合奥氏体锅炉管壁温度曲线变化，指出即使是滑压闷炉缓冷的锅炉也会发生氧化皮堵塞。从强化管理的高度率先提出并实施了将氧化皮检测纳入“四管”防磨防爆体系，在氧化皮问题上做到“逢停必查”，确保机组运行安全，为其他电厂处理此问题提供宝贵的实际经验。 关键词：氧化皮；奥氏体不锈钢；无损检测；堵塞 Investigation for the pipe burst caused by oxide skin stripping off from austenitic stainless steel pipe internal wall based on the new tester Peng Xin Li Youqing Wang Shuangyong Ren Jianwen Xiangtan Power Generation Co.,Ltd 411102 Abstract: The problem that pipe burst caused by oxide skin from austenitic stainless steel pipe, which stripped off from the pipes internal wall and blocked the pipes,has greatly threatened爐he爃ealthy爋peration of power plants. 02 The author analysed the testing condition of Xiangtan power plant, whose supercritical boilers were tested by traditional X-ray and the new special tester self-developed by Xiangtan power plant, underlined the special tester has advantages of high sensitivity and no-requirement for the tested pipes, the operation was also simple and quick，then indicated the features of the oxide skin blockage based on the testing results. Combined the temperature curve of austenitic boiler pipe, this paper pointed爋ut the boiler pipes would be probably blocked by oxide skin even if the boiler shut down with sliding pressure. Ien view of strengthening maintenance management, Xiangtan power plant presented and implemented the measure that integrated oxide skin testing with anti-wear and anti-burst system for ”four pipes” and tested pipes as soon as the units shutted down so as to make sure the units operated securely. These also provided valuable practical experience for other power plants dealing with similar problems. Key words: oxide skin; austenitic stainless steel; nondestructive testing; block 0 引言 目前，在国内外火力发电机组中，高温过热器不锈钢管内壁蒸汽氧化所引发的氧化层剥落造成管子堵塞爆管的现象时有发生。随着我国火电机