华电技术 ›› 2017, Vol. 39 ›› Issue (10): 10-13.

• 研究与开发 • 上一篇    下一篇

过热器氧化物溶解过程中金属材料局部腐蚀机理研究

  

  1. 华电电力科学研究院,杭州 310030
  • 出版日期:2017-10-25 发布日期:2017-11-22

Superheater oxide dissolution metal material local corrosion mechanism study

  1. Huadian Electric Power Research Institute, Hangzhou 310030, China
  • Online:2017-10-25 Published:2017-11-22

摘要:

工程清洗后的割管检查和模拟清洗试验均发现,锅炉过热器局部氧化皮剥落部位出现了深400μm以上的腐蚀坑,对腐蚀坑的形成原因进行试验验证和腐蚀机理分析。分析结果表明:在氧化皮溶解区域与局部氧化皮剥落的金属裸露区域,会形成“大阴极”和“小阳极”的电池腐蚀效应,加速了金属的腐蚀,在局部氧化皮剥落部位生成了严重的腐蚀坑。因此,进行过热器氧化皮化学清洗时,需要同时用实际管样来评价腐蚀控制效果。

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Abstract:

In the cut pipe inspection and simulated cleaning test after engineering cleaning,it was found that the local oxide skin peeling part appeared a corrosion pit of more than 400 microns. The reasons for the formation of corrosion pit are analyzed. Analysis results show that the regional and local scale dissolved metal oxide skin peeling bare area, will form the “large cathode” and“small anode” battery corrosion effect, accelerated the corrosion of metals, the partial oxidation of skin peeling parts generated serious corrosion pit. Therefore, it is necessary to evaluate the corrosion control effect with the actual pipe sample when the chemical cleaning of the oxide skin of superheater is carried out simultaneously.

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