The submarine pipelines for transporting oil, matural gas, seawater is a permanent project with giant investment. This project has been required to protect more than twenty years under the condition without maintenance. But in marine environment with harsh corrosion, we must anticorrode very well to it for safe service above twenty years.
Accoding to a long—term development practice for oil and gas in Bohai Offshore Oil Fields, this article synthetically describes internal and external corrosion control method of various types of submarine pipeline for traspporting oil, gas and seawater, mainly discusses the characteristic, fabrication, construction technical requirement and quality contral requirement for external corrosion coating, riser coating and joint coating for oil, gas and seawater pipelines, also discusses interrelated technical problems for design of cathodic protection system, fabrication, installation, inspection of sacrificial anodes when using Aluminium—Zinc— Indium system anode carries out cathodic protection of submare pipeline, as well as the suing method to prevent internal corrosion of pipeline from corrosive medium in oil, gas and seawater. At the same, the paper also shows adopted national rule and standards in anticorrosion design, fabrication, installation of submarine pipelines.