二次过热器炉管的腐蚀损伤分析与表征.pdfVIP

25 2 Vol. 25 No.2 2004 2 CORROSION PROTECT ION February 2004 失效分析 1 2 1 1 2 , , , , ( 1. , 200433; 2. , 200941) : , 350MW 13 h , , : ; ; ; : TG172 : A : 1005748X(2004) CORROSIVE DAMAGE ANA YSIS AND CHARACTERIZAT ION OF BOI ER TUBES IN A SECONDARY SUPERHEATER 1 2 1 1 2 YANG Zhenguo , ZHU Jimu , WU Liansheng , JIN Zhongkao , CHEN Tianling ( 1. Department of Materials Science, Fudan University, Shanghai 200433; 2. Power Plant, Shanghai Baoshan Iron Steel Co. , td. , Shanghai 200941, China) Abst act: Examination and characterization for the serious corrosive damage of inner surface of boiler tubes in a secondary superheater, w hich had been in service for 130000 hours in a 350MW power generator, were carried out w ith t he help of metallography, scanning electron microscopy, 3D digital video microscopy and energy dispersive analysis. It w as shown that the damage of the inner surface of the tubes w as mainly caused by pitting corrosion, w hich w as attributed to chloride ions and dissolved oxygen in w ater. And the corresponding proposals were put forw ard to prevent the tubes from pitting corrosion and subsequent leakage. Key wo ds: Boiler tube; Superheater; Pitting corrosion; Characterization , 1 2000 9 , 80 21 350MW , , ( CE) , , 1160t/ h 1982 6 ; 1982 11 ; 2 1983 3