National Oilwell Varco (NOV) was recently awarded a contract to supply the submerged swivel and yoke system (SSY) for Argentina’s first FLNG project. SSY systems are a mooring and gas transfer system that allows the FLNG vessel to stay moored. The project is being developed by Southern Energy SA, which includes partners such as Pan American Energy, YPF, Pampa Energia, Harbor Energy, and Golar LNG. The FLNG facility involves redeploying the Hilli Episeyo vessel to produce about 2.4 million tonnes of LNG per year. The SSY system delivers safe mooring and uninterrupted gas transfer through a subsea pipeline. Gas from Vaca Muerta provides a route to export markets for Argentina’s gas resources. However, this development faces several challenges, such as infrastructure limitations, operational risks, and pricing risks. Guy rod clamps, fasten and lock the guy rods that stabilize the mooring tower or turret on a floating vessel.
Vaca Muerta gas production is crucial in expanding domestic gas production, consumption, and export. Both FLNG and SSY systems transfer massive loads from the mooring chains to the vessel structure. This ensures the vessel remains safely on station in harsh environments found offshore Argentina. Guy rods have large-diameter, high-strength rods that act as tendons. They connect the top of the turret structure to strong points on the vessel hull to balance against the pull of the mooring lines. The clamps create a rigid, non-slip connection between the guy rod and the vessel’s hull attachment point. It transfers the tensile and dynamic fatigue loads from the guy rod to the hull without failing. The design ensures the load spreads over a large area to prevent stress concentrations. High-quality rods allow adjustment and alignment of the guy rods, ensuring all rods share the load equally.
Functions of guy rod clamps in FLNG and SSY systems
Using guy rod clamps in these systems provides support in handling the mechanical loads related to offshore energy infrastructure. Guy clamps secure guy rods to anchor points, poles, or structural elements. They grip the rod and ensure tension is properly held and distributed. Proper guy rod clamping prevents slippage or structural failures that could halt exports. Argentina’s offshore environments need strong mooring security from guy rod clamps. Here are the roles of guy rod clamps in the FLNG and SSY systems in Argentina.
- Securing mooring stability—the SSY system depends on mooring elements to keep the FLNG vessel safe while connected to subsea pipelines. Guy rod clamps secure the rods and prevent slippage under high tension. They ensure the mooring system remains reliable in harsh marine conditions.
- Maintaining alignment of mooring components—proper clamping of guy rods maintains alignment between the swivel, yoke, and vessel. This ensures the SSY system operates smoothly during rotation and gas transfer.
- Safety assurance in extreme environments—robust guy rod clamps resist corrosion and mechanical degradation. This ensures continuous LNG export operations.
- Load distribution and stress management—guy rod clamps distribute loads evenly across the rod and attachment point. They reduce stress concentration that could lead to failures.
- Vibration and dynamic load control—FLNG operations involve cyclic loads from vessel motion and LNG transfer. Guy rod clamps keep rods secured to reduce vibration and fatigue.
Technological innovations in FLNG and SSY system development by NOV in Argentina
The Vaca Muerta shale formation in Argentina provides abundant shale gas for export opportunities. NOV provides its submerged swivel and yoke system for offshore mooring and gas transfer solutions. These technologies provide Argentina with flexible offshore mooring, efficient gas transfer, durability, and smart monitoring to maximize uptime. These technologies include:
- Submerged swivel and yoke (SSY) system—this is a submerged mooring and swivel that allows the FLNG vessel to remain anchored while still rotating. The yoke plate provides a structural connection and stability between the mooring foundation and the vessel.
- Advanced swivel technology—NOV’s swivels use high-intensity seals and bearings designed for rotation under high pressure and flow. This helps reduce friction, reduce wear, and ensure continuous operation without frequent maintenance.
- Modular and scalable mooring design—the SSY system can work with different vessel sizes and LNG throughput levels. The NOV’s system allows expansion without redesigning the mooring setup.
- Subsea integration and pipeline safety—the SSY system incorporates robust subsea connectors that link Vaca Muerta gas pipelines to the FLNG unit. The engineering ensures minimal bending stress and secure load transfer to reduce the risk of leaks.