How suction embedded plate anchors can reduce your project's footprint

In this blog, we examine the technical advantages of suction-embedded plate anchors (SEPLA) and how they can reduce a project’s financial and environmental footprint.

The SEPLA is a patented technology from InterMoor, a moorings and anchors brand in Acteon’s Engineering, Moorings and Foundations division, that combines two proven anchoring concepts – suction piles and plate anchors – to increase the anchor point efficiency of pre-set moorings and reduce mooring system costs for floating structures. It is applicable to oil and gas as well as floating renewables.

The SEPLA system uses a suction follower (similar to a suction anchor) to embed a plate anchor deeply in the soil. The suction follower is retracted once the plate anchor is brought to design soil depth and can be used again and again to install additional plate anchors.

Technical advantages

The SEPLA technology combines the advantages of suction embedment and plate anchors. Because they utilise a suction follower, SEPLA anchors are classified as direct embedment anchors. This means the precise location and depth of the anchor are known (whereas the location and depth of drag-embedded anchors can only be estimated). In congested fields, where a clear area to drag in an anchor may not exist, SEPLA is the ideal solution.

• Suction embedment accuracy
  • Suction pile precision
  • No dragging necessary
  • Desired geographical position
  • Desired depth penetration
  • Ideal for crowded and congested areas
• Plate anchor capacity
  • Vertical load capable (VLA)
  • Geotechnically more efficient than suction piles (holding capacity/weight)

Cost advantages

• Less material
  • The SEPLA is more weight efficient than piles (and as a result, cheaper to build)
• Simpler fabrication process
  • The SEPLA requires half the time to fabricate than a suction pile does.
  • The fabrication cost is about half the cost of a suction pile
• Efficient transport/installation
  • Multiple SEPLAs can be carried on a small installation vessel
  • Reduced installation time

Environmental advantages

• Less material
  • A SEPLA anchor requires much less steel (24 tonnes vs 68 tonnes suction pile)
• Smaller carbon footprint
  • By carrying multiple SEPLA on one vessel, the whole mooring system installation requires fewer boat trips, thereby reducing carbon emissions
• Recoverable system
  • Because the suction follower is retracted once the plate anchor is brought to the desired soil depth, nothing mechanical is left subsea