Design Of Cathodic Protection For Tension Leg Platform Based On The Measurement Parameters Of Real Sea

With the development of oil and gas exploitation in South China Sea,offshore platforms are suffering tough marine environment.Tension Leg Platform(TLP)has a strong resistance to the harsh environment because of its semi-compliant and semi-rigid characters,leading to the prominent advantages in oil and gas energy exploitation.Due to the complex and harsh marine environment,the corrosion protection of the TLP is particularly important.This work is mainly based on the sub-task of the national development program.The project provides the design of foreign cathodic protection for the TLP.The corrosion-related environmental parameters used in the design are the ideal values recommended by the standards,which are still quite different from the actual ocean environment.In this work,the corrosion-related environmental parameters in the practice marine environment are measured,and the design of the foreign cathodic protection for the TLP is improved based on the measurement results,which lead to a more reliable scheme of the cathodic protection design.First of all,the feasibility of foreign cathodic protection scheme for the TLP is reviewed based on standard and numerical simulation.The research shows that the foreign cathodic protection scheme could meet the requirements,and the simulation result also meets the protection potential requirements.Secondly,the corrosion–related environmental parameters of the TLP in the practice marine environment are obtained,and the polarization curves of the TLP materials in the real sea environment are measured,which provides a reliable fundamental data for the numerical simulation of the TLP.Thirdly,the scheme of the foreign cathodic protection for the TLP is improved based on the practice measurement parameters.The quantity of the sacrificial anode is determined by the standard,and a reasonable layout scheme of the sacrificial anode is determined based on the numerical simulation design.The new cathodic protection scheme for the TLP based on the practice measurement parameters is established.Moreover,three feasible solutions are proposed to solve the interference problem between two cathodic protection systems.Finally,the scheme of the cathodic protection design for the TLP based on the pratice measurement parameters is analyzed by numerical simulation,and three feasible schemes are calculated by numerical simulation to ensure the safety and reliability of the TLP in the whole service life.