Underground natural gas pipelines require a different approach than exposed lines. Because they are not visible, protection against mechanical damage, corrosion, and future excavations is particularly important.
Mechanical protection
The installation depth, backfilling, and protection against loads are determined by the technical study. The pipeline must be protected from sharp materials, ground settlement, and uncontrolled interference.
Marking
The route must be recorded and, where required, include warning tape or other marking so that future maintenance crews are aware of the network's presence.
Corrosion
The pipeline coating must be protected from damage during installation. In metallic networks, cathodic protection may also be required.
Crossing roads and buildings
At specific points, such as crossings under roads or building entrances, protective sleeves or special construction details may be required.
Inspection after construction
Any excavation near the route must be carried out using a controlled procedure. If there is any doubt about the location of the line, it must be confirmed before mechanical excavation begins.
Documentation
As-built drawings must be updated so that the actual position of the underground pipeline is known and not based on verbal information.
