CORROSION INVESTIGATION OF UNDERGROUND HEAT INSULATING PIPELINES

The corrosion of oil pipelines coated with polyethylene and rigid polyurethane foam thermal insulation always endangers the safety of operation of pipelines.The corrosion of pipelines caused by foam water,microorganism and stray current was investigated.The influence of the shield resulted by the coating of polyethylene jacket insulation ,and the effect resulted from IR drop on cathodic protection was elaborated.