Recent research published in ‘Cailiao Baohu’, which translates to ‘Material Protection’, sheds light on a pressing issue in the construction and energy sectors: the corrosion behavior of X70 pipeline steel under dynamic AC interference. This study, led by CAO Guofei and his team from PipeChina West East Gas Pipeline Company in Shanghai, offers critical insights that could significantly influence the anti-corrosion design of pipelines, especially those situated near electrified railways.
The researchers utilized a dynamic AC corrosion simulation test device to analyze how X70 steel, a material commonly used in pipeline construction, reacts to varying levels of AC interference. Their findings indicate a direct correlation between the dynamic AC interference current density and the corrosion rate of the steel. “When the dynamic AC current density exceeds 100 A/m², the corrosion rate can surpass 0.03 mm/a, regardless of cathodic protection conditions,” CAO noted. This revelation is particularly alarming for pipeline operators, as it underscores the potential vulnerabilities of existing infrastructure in high-traffic, electrified areas.
The study also highlighted an intriguing phenomenon: under dynamic communication interference, the corrosion rate displayed a “saddle shaped” pattern in relation to the level of cathodic protection applied. Initially, as cathodic protection levels increased, the corrosion rate decreased. However, after reaching a certain threshold, the rate began to rise again. “Only when the AC current density is at 30 A/m² and the cathodic protection level is between -0.90 and -1.15 V (vs CSE) does the corrosion rate remain below the critical threshold,” CAO explained. This nuanced understanding of the relationship between AC interference and corrosion rates is vital for engineers and project managers involved in pipeline construction and maintenance.
The implications of this research are far-reaching. As electrified railways continue to expand, the construction industry must adapt to ensure the longevity and safety of pipeline systems. Enhanced anti-corrosion strategies informed by these findings could lead to significant cost savings in maintenance and repairs, ultimately contributing to the sustainability of infrastructure projects.
As the construction sector grapples with the challenges posed by environmental and operational factors, studies like this one pave the way for more resilient and efficient designs. The insights provided by CAO and his colleagues not only advance our understanding of pipeline integrity under dynamic conditions but also serve as a crucial reference point for future developments in anti-corrosion technology.
