海管焊接接头腐蚀特性及监测方法研究进展

Research Progress on Corrosion Characteristics and Monitoring Methods of Submarine Pipeline Weldment

首先,介绍了海底管道焊接区域的腐蚀理论,其中成分差异理论和活性组织溶解理论是导致焊接区域发生局部腐蚀的主要内因。其次,总结了影响焊接区域腐蚀性能的因素,主要包括焊接区域元素成分、显微组织等材料自身因素以及温度、流速等环境因素。进而,结合焊接区域的属性特点和环境条件,归纳了电偶腐蚀、应力腐蚀、晶间腐蚀等主要的腐蚀类型。最后,重点介绍了元素成分和显微组织结构复杂的焊接区域非均匀腐蚀监测方法,明确了如电化学法、电阻法等的技术特点和适用条件,从而从腐蚀特性及腐蚀监测层面为海管焊接区域的工艺设计和腐蚀管理提供技术指导。

Firstly,the corrosion theory of submarine pipeline weldment was introduced,among which the composition difference theory and the active tissue dissolution theory were the main internal causes of local corrosion in the weldment.Secondly,the factors affecting the corrosion performance of the weldment were summarized,including the elements,microstructures and other material factors,and environmental factors such as temperature and flow rate.Furthermore,based on the characteristics of weldment and environmental conditions,the main corrosion types such as galvanic corrosion,stress corrosion and intergranular corrosion were summarized.Finally,the review focused on the nonuniform corrosion monitoring methods in the weldment with complex element composition and microstructure structure,and defined the technical characteristics and applicable conditions such as electrochemical method and resistance method,so as to provide technical guidance for the process design and corrosion management in the weldment of submarine pipeline from the aspects of corrosion characteristics and corrosion monitoring.