Cathodic protection technical design for two underground gas and oil transmission pipeline

Cathodic protection is an effective method to control the corrosion of metal surfaces creating an electrochemical cell on the metal surface. The main principle of cathodic protection is that the surface potential became negative enough concerning other components to ensure no electrical current flows from the protected part to adjacent components. This would be achieved if an external electrical current enters the protected surface throw an electrolyte and therefore the anodic sites of the metal surface will be eliminated. For steel surfaces, the surface potential below -۰.۸۵ volts concerning sulfate reference electrode can prepare cathodic protection in aerated soil and water. In an unaerated atmosphere, where there are sulfate reductant bacteria (SRB) it is necessary to reduce protection potential to -۰.۹۵ volts. In this paper, the cathodic protection design of two transmission pipelines was performed. Based on the design of a ۲-year temporary system at the time before connection to the power grid, the sacrificial anodes including ۴۱۰ standard ۶۰-pound magnesium anodes were calculated. A permanent system for ۲۵ years of design based on impressed current technique including ۶۰ MMOs was also introduced

کلیدواژه ها:

Cathodic Protection ، Corrosion ، Pipeline ، Sacrificial Anode ، Impressed Current.