Single Point Buoyancy Units, also known as Mono Buoyancy Units (MBUs), represent a groundbreaking advancement in marine buoyancy technology, offering unparalleled efficiency and safety for offshore pipeline installations, salvage operations, and towing applications. Developed by DOOWIN, these enclosed flotation devices combine the versatility of inflatable buoyancy with the structural robustness required for high-load scenarios.
Key Innovations
Axial Load Transmission: Unlike conventional buoyancy modules, MBUs feature a proprietary through-strop design that allows lifting directly through the bag’s central axis, achieving a safety factor exceeding 5:1 in rigorous testing.
Compact Logistics: With a packed weight of just 1% of their lifting capacity, 500 metric tons of MBUs can be transported in a single 20ft container, enabling rapid deployment even for urgent projects.
Depth Resilience: Constructed from high-tensile polyester with UV-stabilized PVC coating and reinforced with concentric fabric layers at each end, MBUs withstand harsh marine environments.
Dynamic Buoyancy Control: Integrated air valves allow remote venting or replenishment, enabling precise load positioning during critical phases like pipeline touchdown.
Operational Advantages
Pipeline Shore Approaches: MBUs excel in float-out and shore-pull operations, reducing risks to divers and workboats by eliminating high-energy projectile hazards during buoyancy release.
Towing & Salvage: Their single-point attachment simplifies rigging, making them ideal for vessel recovery and submerged structure stabilization.
Versatility: Available in 1t, 2t, 3t, and 5t lift capacities, MBUs adapt to diverse project scales while complying with IMCA D-016 standards.
Commercial Benefits
Cost Efficiency: MBUs outperform steel or foam alternatives in both purchase and rental costs, with our hire-focused model ensuring long-term durability.
Safety & Speed: Lightweight design (e.g., 45kg for a 5t unit) allows manual handling, while minimal connection points accelerate rigging.
Specification of Single Point Buoyancy Units

| Model | Capacity | Diameter | Length | Dry Weight |
|---|---|---|---|---|
| SPB-500 | 500 kg | 800 mm | 1,100 mm | 15 kg |
| SPB-1 | 1,000 kg | 1,000 mm | 1,600 mm | 20 kg |
| SPB-2 | 2,000 kg | 1,300 mm | 1,650 mm | 30 kg |
| SPB-3 | 3,000 kg | 1,500 mm | 2,300 mm | 35 kg |
| SPB-5 | 5,000 kg | 1,700 mm | 2,650 mm | 45 kg |
