The Moho Nord tension leg platform arrived at its field location as an integrated unit — hull and topsides already joined — for installation in roughly 800 m of water off the Republic of Congo. There was no staged assembly offshore. The entire structure had to be positioned, ballasted, and connected to its tendons in one continuous campaign.

Hyundai Heavy Industries, which built the platform, contracted Heerema Marine Contractors to handle the transport and installation. The offshore work was split across two phases using two of the heaviest semi-submersible crane vessels in the industry: Thialf and Hermod.

≈800 m
Water depth
61×61 m
TLP hull footprint
30 m
Final operating draft
2014–16
Offshore installation window
Phase 1 — Seabed preparation and piling
Setting the foundations before the platform arrives
Before the TLP reached the field, mooring and tendon piles were driven into the seabed — reportedly including large-diameter mooring piles and dedicated TLP tendon piles — establishing the fixed points the floating structure would be tensioned against.
Phase 2 — TLP lowering and tendon connection
Twelve tendons, ten segments each
The integrated TLP was lowered into position and connected to 12 vertical tendons, each built from 10 segments of 24-inch-diameter pipe, using high-strength mechanical connectors engineered for fatigue resistance under continuous tension.
Phase 3 — Mooring hookup
Two separate mooring systems, one field
Alongside the TLP's tendon system, the associated floating production unit and storage structure required their own catenary mooring lines — combinations of chain, wire rope, and polyester line connected via H-links — each totalling roughly 1.5 km in length.

An integrated hull-and-topsides unit, lowered onto twelve tendons in 800 m of water — with no staged assembly offshore, the entire installation sequence had to work in one continuous campaign.

The Moho Nord installation stands as a reference case for integrated TLP delivery: rather than building the topsides on the hull offshore, the platform arrived essentially complete, shifting the engineering challenge from fabrication sequencing to a single, tightly coordinated marine installation campaign using two of the industry's largest heavy lift vessels.

For further reading on floating platform installation, see What is Heavy Lift Engineering?

Related case studies: Tyra TEG Module Lift · Gullfaks C · Bullwinkle Platform

Sources: Heerema Marine Contractors — installation contractor's project record for the tendons, mooring piles and vessel spread; TotalEnergies — operator's field description; Offshore Technology. Published water depths vary between roughly 780 m and 800 m for the TLP location.

Frequently Asked Questions

The Moho Nord field lies roughly 75 km off the coast of the Republic of Congo, West Africa, in a water depth of approximately 800 m.

Hyundai Heavy Industries (HHI), which built the TLP hull and topsides, contracted Heerema Marine Contractors (HMC) to transport and install the platform and its moorings. The offshore installation was carried out in two phases using the semi-submersible crane vessels Thialf and Hermod.

The TLP was vertically moored using 12 tendons, each made up of 10 segments of 24-inch-diameter pipe, connected to piled foundations on the seabed. Separate catenary mooring systems — combinations of chain, wire, and polyester rope connected via H-links, each totalling roughly 1.5 km in length — provided station-keeping for the associated floating production unit and storage structure.

The TLP was delivered as an integrated unit — hull with topsides pre-installed — meaning the entire structure, rather than separate modules, had to be positioned, ballasted, and connected to its tendons in a single continuous offshore campaign at 800 m water depth, with piling, tendon connection, and mooring hookup all sequenced around the availability of the two heavy lift vessels.