Surface Technology

The history and the main research work and applications of the pulsed current cathodic protection (PCCP) were reviewed. Even though it has more than 30 years history, there are only fewer of research and application reports about PCCP, especially there is nearly no study on the mechanism of PCCP. It is because of the lack of the understanding of the mechanism of PCCP that until now PCCP has not been accepted commonly and applied widely. However, almost all the application reports indicated that PCCP had many advantages over the traditional direct current cathodic protection (DCCP), and these advantages had been verified sufficiently in oil well casing systems. In addition, DCCP may be combined with PCCP to obtain better protection effect. So it is necessary to study the mechanism and application of PCCP.