Cathodic protection of buried pipelines

Buried and submarine pipelines refer to pipelines installed underground or under sea water. The average low resistance in the ground and sea water simplifies the cathodic protection operation of buried and submarine pipelines.

The most suitable anode for protecting buried and subsea pipelines is the bracelet anode. The factors that affect the current demand in underground and seawater are temperature, salinity and ocean currents. Normally, temperature is the most important factor. Bracelet anodes on submarine pipelines are usually arranged along the pipeline with a certain interval in between. The standard material for bracelet anodes is aluminum-zinc-indium, but zinc anodes are sometimes used. If the surface temperature of the pipe exceeds 50°C, the bracelet-type zinc anode is not suitable. When the pipeline is in a high temperature environment, we recommend using other types of anodes, arranged along the pipeline and connected to the pipeline with cables.

The electrical connection between the pipeline and the anode is carried out with copper cables. The copper cables are thermally welded between the iron core and the pipeline. The cathodic protection of the pipeline needs to provide sufficient current on the surface of the pipeline, so that the potential between the pipeline and the electrode can be reduced, so that the external Corrosion becomes very weak.

When making electrical measurements, appropriate safety precautions should be observed. These measures include the following: Before installing, adjusting, repairing, removing or testing impressed current cathodic protection equipment, you should understand and master the necessary electrical safety precautions.

The selection of cathodic protection parameters mainly includes protection potential and protection current density.

Cathodic protection potential of buried and submarine pipeline steel structure