At the beginning and end of the protected pipeline, at the inlet and outlet of pumping stations, pressure regulating and metering stations, gas gathering stations, pipe cleaners and receiving stations.
-In the middle of the protected pipeline at the pumping station, compressor station, regulating and metering station, gas gathering station, pipe cleaner receiving and dispatching station of the import and export. However, in order to ensure the continuity of the conductivity of the pipelines at both ends of the station, the protected pipelines should be connected with cable spans on the outside of the two flanges.
-Through in the middle of the protected pipeline in the small number of current is very large, across the pipeline ends
-Connection of the protected pipeline with other main and branch pipelines which should not receive cathodic protection.
-Stray current interference zones
-Dissimilar metal, new and old pipeline connection; bare pipe and coated pipe connections
The location where electrical grounding is adopted
