海洋钢结构浪花飞溅区腐蚀防护技术

Anti-Corrosion Technology to Steel Structure in Splash Zone

随着我国对海洋资源的开发,海洋钢结构的腐蚀控制技术越来越受到关注。海洋环境可以分为海洋大气区、浪花飞溅区、海水潮差区、海水全浸区和海底泥土区等5个腐蚀区带。其中,海洋钢结构在浪花飞溅区腐蚀最为严重。在浪花飞溅区,钢表面受到海水的周期性润湿,处于干湿交替状态,氧供应充分,盐分不断浓缩,加之阳光、风吹和海水环境等协同作用导致发生最严重的腐蚀。锈层的自氧化反应是加速钢结构在浪花飞溅区腐蚀的一个主要原因。当前,国内对于海洋钢铁设施大气区通常采用涂料保护,海水全浸区采用电化学保护,都取得了较好的保护效果,但是这些保护技术对于钢结构在浪花飞溅区的腐蚀防护效果并不佳。而复层矿脂包覆防腐(PTC)技术是当前海洋钢铁设施浪花飞溅区防腐蚀应用较为理想的方法,对此进行了重点介绍。

With the development of marine oil and gas exploration, more and more attention has been given to marine corrosive environment during the last decades. Marine corrosion environments are generally divided into atmospheric, splash, tidal, immersion, and mud zones. The protection to splash zone corrosion must be conducted with high priority. In the splash zone, aside from seawater that causes normal marine corrosion, other factors such as temperature variations, tidal action, wave impacts, man-made pollutants, sufficient oxygen （ 02 ）, ultraviolet rays, and salt spray that continually washes upon objects, will cause severe corrosion damage. Note that rust self-oxidation greatly accounts for the corrosion of steel structures in the splash zone. At present, the domestic iron and steel facilities is usually used to protect paint for ma- rine atmospheric zone, and electrochemical protection for seawater immersion zone. These have made better protection, but the protection effect for corrosion protection in splash zone is poor. However, the petrolatum tape cover （PTC） is the most useful technology to protect the steel in splash zone, as is emphatically introduced here.