Foam float— reliable floating devices for vessel

Foam float— reliable floating devices for vessel

With the continuous expansion of global maritime trade, ports and offshore transshipment operations are raising higher requirements for the safety and reliability of mooring and anticollision equipment. As a kind of maintenancefree, unsinkable offshore floating unit, foamfilled mooring buoy has gained growing popularity across global ports and offshore projects.

Different from hollow steel buoys and inflatable floating bodies, solid foamfilled buoys eliminate the risk of sinking caused by water ingress after damage, thanks to its special material and structural design.

What is a Foam-Filled Mooring Buoy

A foam-filled mooring buoy is a solid, non-hollow marine floating equipment. Unlike inflatable products that rely on internal air pressure for buoyancy, it obtains permanent buoyancy from closed-cell foam materials. It is assembled with high-strength protective outer cover and metal end fittings.

It is mainly applied for vessel mooring & positioning, port anti-collision, setting offshore mooring points, and serving as auxiliary floating structures for ship-to-ship transshipment. The large-sized cylindrical foam buoy shown in the picture is widely deployed in deep-sea ports and large-vessel operations.

Material & Structural Composition

The whole unit consists of four key parts: inner buoyancy core, intermediate reinforcement layer, outer protective skin and end metal components.

1. Inner Buoyancy Core The core is high-density closed-cell EVA / PE foam, composed of millions of independent sealed micro-cells with a closed-cell rate above 95%. Even if the outer skin is scratched or impacted, seawater cannot penetrate into the foam core. The buoyancy can be largely retained so the unit will never sink. The foam material features excellent seawater immersion resistance and salt-water corrosion resistance for long-term marine service.

2. Intermediate Reinforcement Layer High-strength fabric or nylon cord layers wrap around the foam core. It tightly bonds the foam and outer elastic skin, improving tear-resistance and tensile performance to prevent delamination under heavy compression and impact.

3. Outer Protective Skin The outer surface is coated with polyurethane or polyurea elastomer to form a tough, wear-resistant shell. It resists UV ageing, salt spray, friction from waves and gravel, and protects inner foam from seawater and marine organism erosion. High-visibility orange-red color is commonly adopted for good recognizability at sea.

4. End Metal Fittings Hot-dip galvanized carbon steel flanges, lifting lugs and mooring interfaces are installed on both ends. Lifting lugs are used for hoisting and transportation; flanges connect anchor chains, shackles and swivel joints to fix the buoy on seabed and bear mooring tension. They are critical load-transfer components.

Applications in Marine Berthing Operations

1. Port Mooring Points: Act as offshore mooring buoys. Large vessels can moor to the buoys instead of berthing alongside docks, easing the shortage of berth resources and providing safe mooring spots in open sea areas without shore facilities.

2. Vessel Anti-collision & Buffering: It can function as fender as well. Floating freely with water level, it keeps continuous contact with ship hull under large tidal range, absorbs impact energy during berthing and protects both vessel hull and port structures.

3. Offshore Ship-to-Ship Transshipment: Placed between two vessels during alongside cargo transfer, it serves as buffer isolation. Compared with inflatable fenders, it removes hidden danger from air leakage and delivers higher safety.

4. Auxiliary for Offshore Industries: Used as positioning floats and mooring supports for offshore engineering platforms, offshore wind farms and aquaculture facilities.