不锈钢换热器波纹管失效分析

Stainless steel heat exchangers corrugated pipe invalidation analysis

分析了大型换热器中不锈钢波纹管发生破裂事故的原因,认为是波纹管表面残存拉应力,热交换介质中存在Cl^-与H_2S溶液和不锈钢中含Ti量偏低而产生的应力腐蚀所致,提出了相应的防腐措施,即对加工后的波纹管需进行退火处理,以消除残存拉应力;在材质中增加Ti的量;换热介质中严格控制Cl^-,H_2S的含量等。

The experiment and analysis we have carried out show hat the cracking failures of the large stainless steel heat exchanger's corrugated pipe is caused mainly by stress corrosion, which is caused by the remaining draw stress on the surface of the corrugated pipe, Cl- ,H2S solution in the heat exchange medium and too little Ti content in the stainless steel. In order to solve this problem, we have put forward the corresponding measures for preventing corrosion, such as annealing the corrugated pipe right after it has been made in order to eliminate the remaining draw stress, increasing the Ti content in the material; and strictly limiting the Cl- ,H2S content in the heat exchange medium.