酸性盐腐蚀球墨铸铁管连接件抗弯性能试验

Test on bending resistance of ductile iron pipe connector corroded by acidic chlorine salt

为了探究酸性氯盐腐蚀条件下的法兰连接球墨铸铁管受弯性能的变化规律,采用酸性NaCl溶液对法兰连接球墨铸铁管通过干湿交替处理后进行受弯试验,对腐蚀试件的极限承载力、屈服弯矩和极限弯矩、应变等方面与标准件进行对比分析.结果表明:干湿循环腐蚀后,球墨铸铁管连接件极限弯矩与屈服弯矩的比值随着干湿循环次数的增多而变小,约在1.2~1.4之间;经100次的干湿循环腐蚀,球墨铸铁法兰管连接件的极限承载力下降了35.13%.经酸性氯盐干湿循环处理后的球墨铸铁管更容易在法兰盘与管体的连接处发生脆性破坏.

In order to investigate the bending performance variation of flange connected ductile iron pipes under acidic chlorine salt corrosion conditions,the bending test was performed after the flange-connected ductile iron pipes were treated by the alternation of wetting and drying in acidic NaCl solution,and the ultimate bearing capacity,yield bending moment,ultimate bending moment and strain of corroded specimens were compared and analyzed with the standard counterparts.The results show that the ratio of ultimate bending moment to yield bending moment of flange connected ductile iron pipes,which is finally about 1.2 to 1.4,becomes smaller with the increase of wetting and drying cycles.After 100 times of the alternation of wetting and drying,the ultimate bearing capacity of flange connected ductile iron pipes decreases by 35.13%.The flange connected ductile iron pipes treated by the alternation of wetting and drying in acidic chlorine salt solution is more prone to brittle damage at the connection between flange and pipe body.