Definition - What does Internal Corrosion mean?
Internal corrosion is defined as the corrosion that takes place within the inner walls of a pipeline. This corrosion is typically the result of complex chemical reactions between the pipeline material (metallic or non-metallic) and the surrounding environment. The end result of these chemical reactions is accelerated deterioration and degradation of the material properties of the inner walls of the pipeline.
Trenchlesspedia explains Internal Corrosion
Although there are numerous types of corrosion (uniform corrosion, galvanic corrosion, pitting corrosion etc.), internal corrosion in pipelines (particularly sewer pipes) is as a direct result of microbiological corrosion.
This type of corrosion occurs due to the presence of microorganisms (bacteria) in the pipe wall and in the wastewater. The activity of the bacteria within the pipe results in the production of hydrogen sulfide gasses. The sulfide in the wastewater makes its way to the surface where it makes contact with the atmosphere (air and moisture) to form sulfuric acid. The resulting sulfuric acid is highly aggressive and can have devastating effects on both steel and concrete pipes.
Numerous trenchless technology techniques are available to efficiently repair, rehabilitate and replace corroded pipelines including:
- Cured-in-Place Pipe (CIPP) lining
- Sport repair
- Pipe bursting