Term 252

Automated Corrosion Monitoring and Mitigation Framework for Steel Alloys in Deepwater Drilling Environments

Project Type: Self-Initiated

Project Description

Deepwater drilling risers are critical offshore components exposed to aggressive marine environments where corrosion and corrosion–fatigue can lead to sudden structural failure. Current industry practice relies on passive sacrificial anodes, typically Zinc or Aluminum alloys, which increase riser weight and hydrodynamic drag while providing no real-time verification of protection effectiveness. This project proposes an automated corrosion monitoring and mitigation framework based on an actively controlled Impressed Current Cathodic Protection (ICCP) system integrated with ultrasonic wall-thickness monitoring and electrochemical potential feedback. To ensure complete protection of the riser circumference, a multi-point monitoring configuration will be implemented, providing wired, circumferential coverage around the API 5L X80 steel riser. A closed-loop control strategy will regulate protective current to maintain the steel within a safe electrochemical window, preventing both corrosion and hydrogen-induced cracking. The framework will be validated through a hybrid approach combining a laboratory-scale prototype operating in simulated seawater and numerical simulations representing deepwater operating conditions. Electrochemical testing of the St 52 surrogate cathode confirmed the optimal protective potential range of -850 mV to -1100 mV vs. Ag/AgCl. Within this window, the instantaneous corrosion current was minimized without triggering hydrogen evolution. Faraday’s Law calculations demonstrated a reduction in the penetration rate to acceptable limits, successfully achieving the targeted cathodic protection for the API 5L X80 steel riser while avoiding hydrogen embrittlement.