Name | Underwater Lift Bags |
Material | PVC Coating Fabric |
Lifting Capacity | 200kg to 50 tons |
Type | Cylindrical |
Layers | 1-6Ply, or as Request |
Feature | Durable Construction, Easy Filling and Emptying |
Reinforcement | Nylon Fabric |
Thickness | 0.4mm-2.5mm, or As Request |
Color | Black, Yellow, Orange, Or As Request |
Usage | Underwater Air Lifting, Salvage, Large Buoyancy |
Application | Structural Load Testing, Proof Load Testing |
In busy marinas, docks, and ports, heavy equipment such as anchors, chains, or even machinery sometimes ends up on the seabed. Retrieving these items can be costly and time-consuming without the right tools. Underwater Lift Bags offer a practical solution, providing powerful lift in a compact, portable package.
The basic setup involves a tough, inflatable bag with secure attachment points and overpressure protection. Divers connect the lift bag to the object, inflate it using their scuba gear or surface-supplied air, and control the ascent by adjusting air volume. This method reduces the need for cranes or barges, cuts operation costs, and allows work to be completed with minimal disruption to surrounding vessels. Lift bags are available in multiple shapes and sizes--parachute-style for vertical lifts, enclosed-style for more stability, and pillow-style for shallow water use--making them adaptable to different recovery tasks.
Case Study: After a severe thunderstorm, several mooring anchors in a private marina were dislodged and sank to depths of 15 meters. Replacing them would have cost the marina tens of thousands of dollars. Instead, a professional dive team was hired to recover them using Underwater Lift Bags. Each anchor weighed around 1.2 tons and was buried partly in silt. Divers first cleared the sediment and attached heavy-duty slings to the anchor's shank. Two large-capacity lift bags were connected, one on each side, to maintain balance. By slowly adding air, the divers brought the anchor to a stable hover just above the seabed, then guided it toward the dock area where a small crane lifted it onto land. The operation saved the marina approximately 70% of the replacement cost and allowed boat owners to resume mooring within 48 hours. The marina manager later stated that lift bags had proven to be "the most efficient and cost-effective recovery tool" they had used.
Product Name | Underwater Lift Bags |
Raw Material | PVC coating fabric |
Type | Cylindrical |
Size | 500kg, 1000kg, 5000kg 10000kg,etc |
Thickness | 0.4-1.2mm, or as request |
Color | Yellow, Blue, Black, etc |
Density | 0.33-0.9g/cm3 |
Safety Factor | 7:1 |
Tolerances | +/- 0.03 on densities +/- 0.2 mm on thickness +/- 0 to +3mm on width +/- 0 to +3mm on length |
Model | Buoyancy [kg] | Buoyancy [lbs] | Diameter [mm] | Length [mm] | Appr. Weight [kg] |
---|---|---|---|---|---|
HM-ULB01 | 200 | 441 | 500 | 1,000 | 5 |
HM-ULB02 | 500 | 1,103 | 800 | 1,000 | 8 |
HM-ULB03 | 1,000 | 2,205 | 1,000 | 1,500 | 11 |
HM-ULB04 | 2,000 | 4,410 | 1,300 | 1,500 | 20 |
HM-ULB05 | 4,000 | 8,820 | 1,600 | 2,000 | 50 |
HM-ULB06 | 6,000 | 13,230 | 2,000 | 2,000 | 66 |
HM-ULB07 | 8,000 | 17,640 | 2,000 | 2,600 | 75 |
HM-ULB08 | 10,000 | 22,050 | 2,400 | 2,400 | 80 |
HM-ULB09 | 15,000 | 33,075 | 2,600 | 3,000 | 110 |
HM-ULB10 | 20,000 | 44,100 | 3,000 | 3,000 | 130 |
HM-ULB11 | 30,000 | 66,150 | 3,000 | 4,500 | 170 |
HM-ULB12 | 50,000 | 110,250 | 4,000 | 4,000 | 220 |
HM-ULB13 | 70,000 | 154,350 | 4,000 | 5,700 | 310 |
HM-ULB14 | 100,000 | 220,500 | 4,000 | 8,000 | 450 |
HM-ULB15 | 150,000 | 330,750 | 5,000 | 8,000 | 660 |
HM-ULB16 | 200,000 | 441,000 | 5,000 | 10,000 | 900 |
Note: Other sizes can be customized according to the requirements.
Integrated line guides and wear pads for proper umbilical/running line routing during deployment.
Energy-absorbing foam layers protect against shock loads during dynamic lifting operations.
UV-stabilized materials and abrasion-resistant coatings provide 10+ years of reliable service with proper maintenance.
Each unit ships with complete test certificates, pressure ratings, and maintenance logs for professional asset tracking.
Lifts and positions dock sections, pilings, and connectors during maintenance. Ensures stability during repair operations.
Holds ROVs (Remotely Operated Vehicles) and inspection equipment steady during structural assessments of dams, ships, and offshore rigs.
Used in dive training for buoyancy control exercises and salvage simulations. Helps recover lost diving gear in recreational dive sites.
CNU-controlled cutting ensures millimeter-perfect pattern accuracy for consistent quality.
Industry-leading 7-year warranty against material defects with proper maintenance.
Each delivery includes test certificates, maintenance manuals, and compliance documentation.
24/7 technical assistance from our team of marine salvage experts.
From material selection to final testing, we maintain full traceability with 17 documented QC checkpoints.
Our marine salvage engineers offer free technical consultations for complex lifting operations.
We maintain priority production slots and global logistics partnerships for urgent mission requirements.
30+ years of specialized focus, military-grade materials, and uncompromising quality control at every production stage.