Pipeline Free Span Mitigation

Surface laid pipelines can experience free-spans due to various reasons; uneven seabed and local scour. If free-spans are long, the vortex induced vibrations (VIV) can cause the pipeline to undergo fatigue damage and severely reduce the pipeline design life.

Free-spans can be rectified by,
• Pipeline Lowering (PL) Method
• Grout/Sand bag placement
• Rock dump placement
The selected method for rectification depend on the pipeline details, location, water depths and cost details.
Source:
http://www.capegroup.net/products-services-46/total-oilfield-pipeline-solutions-50/free-span-assessment-rectification-118