Adaptability of Impressed Current Cathodic Protection Technology for Buried Pipeline with Thermal Insulation

Taking the gas gathering lines of Longgang gas field as an example, the current situation and effect of cathodic protection were studied. The moisture content testing and scanning electron microscopy (SEM) were used to study the current shielding characteristic of the anti-corrosion thermal insulation layer. The results show that impressed current cathodic protection can not protect buried pipelines with thermal insulation layer fully, only protect the breakage sites in the outer protective layer, thermal insulation layer and 3PE anti-corrosion layer.