Rehabilitation of the cathodic protection system of a sour gas-gathering system

The South Oldenburg gas production district in northern Germany comprises reservoirs, operations sites, gathering and transfer stations, and underground pipelines. The district's cathodic protection system underwent a major rehabilitation in the late 1990s. Electrical isolation was installed at separate facilities carrying different contents as well as pipelines having different coatings. Underground isolation was moved and isolating flange kits replaced aboveground, monolithic isolation joints. This article describes the rehabilitation process and the isolating fittings involved.