1. Linings may be used for internal corrosion protection, provided the lining material does not degrade following long-term exposure to the transported fluid, at the pipeline pressure and temperature conditions.
2. Care is required to ensure continuity of the lining at the joints.
3. Polyethylene linings are susceptible to attack by aromatics, and to permeation of any dissolved gas in the transported fluid.
4. To prevent lining collapse when the pipeline is depressurised, the permeated gas should be relieved from the annulus.
5. Internal coatings shall not be used for the purpose of preventing corrosion, because holidays in the coating cannot be completely avoided.
6. In some situations, internal coatings may be applied for internal corrosion mitigation, when the expected leaks are deemed acceptable, following a review of the safety and environmental aspects.
7. Internal paint markings for individual pipe identification should not be used when corrosive conditions will be present in service.
