大型锅炉减温器失效原因分析.pdf

维普资讯hlp
第27卷/2007年第3期
湖南电力
研究与试验
大型锅炉减温器失效原因分析
黄伟',匡国强2,李光',孔鹏程3,钟建明
(1.湖南省电力试验研究院,湖南长沙410007;2.华电长沙发电有限公司,湖南长沙410005;
华电石门发电有限责任公司,湖南石门415300;4.湖南省火电建设公司,湖南株洲412000
摘要:减温器在实际运行中由于结构、材质、装配间隙、运行环境恶劣等原因,经常
出现裂纹,造威笛形管成块脱落,致使减温器联箱本体裂纹,直接影响减温水的控制与
过热蒸汽温度的调节效果。运行表明,制作笛形管的材料耐热钢比不绣钢好,噴孔直径
大小、装配间隙的调节和喷管厚度的选取也十分重要。将原不锈钢喷管更換成耐热钢喷
管,加大喷孔直径,加厚喷管厚度,调紧装配间隙,并对裂纹深10mm以上的减温器联
箱进行扩孔处理,对10mm以下的进行堆焊处理,将未裂纹的减温器联箱进行焊缝重叠
处理,取得明显效果。
关键词:喷水减温器;失效分析;措池
中图分类号:TK227.1文献标识码:A文章编号:1008-0198(2007)03-0011-04
Analysis of desuperheater failure on large-sized boiler
HUANG Wei, KUANG Guo-qiang, LI Guang KONG Peng-cheng, ZHONG Jian-ming
(1. Hunan Electric Power Test and Research Institute, Changsha 410007, China; 2. Huadian Changsha
Power Generation Co. Ltd, Changsha 410005, China; 3. Huadian Shimen Power Generation Co. Ltd
Shimen 415300, China; 4. Hunan Thermal Power Construction Company, Zhuzhou 412000, China)
Abstract: Cracks were frequently occurred in desuperheater because of structure, material, fit-up gaps, and hostile
operation background, etc, which made flute-tube fell off and the body of desuperheater channel cracked. The control
of desuperheater spray and ad ustment effectiveness of super heater temperature then would be directly affected
Operation indicated that, as far as flute-tube material was concerned, refractory steel was better than stainless steel.
The size of orifice diameter, the adjustment of fit-up gaps, and the chosen of nozzle depth were also important.
Obvious better performance was obtained by replacing the stainless steel nozzle into refractory steel, enlarging orifice
diameter, deepening nozzle depth, adjusting fit-up gaps, chambering treatment on over 10mm cracks of desuperheater
channel, and overlaying welding treatment on less than 10mm
Key words: spray desuperheater; failure analysis; measure
前
2喷水减温器的种类及事故特点
近年来,湖南省已投运的300MW锅炉减温器,
喷水减温器多为混合式,共有5种:单喷头直套
由于笛形管破裂而引起的爆管达5次,在已检查的减温器,水室式文氏管套筒减温器,涡式喷头文
12个减温器联箱中,有9个减温器联箱出现裂纹、断氏管套筒减温器,笛形管直套筒减温器,环向进水
脱等现象。如何避免减温器裂纹、断脱,如何处理式直套筒减温器。湖南省已投运的300MW锅炉多
已裂纹的减温器联箱,已成为火电厂急崙解决的难采用笛形管直套筒减温器,为了防止尚未汽化的减
题
温水滴直接击中减温器的联箱内壁,致使联箱内壁
受交变热应力作用而产生裂纹,该减温器内在喷水
收稿日期:2007-01-1