September 28, 2026
Pillow type underwater air lift bags are fully enclosed buoyancy units, famous for flat low-profile shape and stable static buoyancy. Rated capacity normally ranges from 100kg up to 5 tons, mainly designed for shallow-water subsea engineering and light-to-medium salvage jobs. Unlike open-bottom parachute bags, the closed structure locks air steadily underwater. Multiple reinforced attachment points allow divers to install them flat or upright, even placing inside cabins or confined subsea gaps, which makes them highly versatile for harbour, river and nearshore projects.
The most common applications focus on precision positioning and shallow-water recovery. In offshore wind and harbour maintenance, pillow lift bags are deployed beneath subsea pipelines and concrete foundations for horizontal leveling, fine adjustment and load reduction. They are widely used for sunken car, small boat and submerged machinery recovery in inland rivers, reservoirs and coastal ports. Divers can also place pillow bags inside a partially sunken vessel’s cabin to add emergency buoyancy, refloat small crafts or assist wreck towing after refloating. Other typical uses include underwater cable laying, bridge pier repair and sunken aircraft fragment salvage.
Engineers select pillow lift bags when working space is limited and uniform load distribution is required. The wide contact surface prevents sliding on flat structures. Built-in pressure relief valves control internal pressure and avoid burst risks. It should be noted that pillow bags are not recommended for deepwater or ultra-heavy large wreck lifting. Combined use of multiple pillow bags offers flexible buoyancy configuration for commercial diving teams, port contractors and nearshore marine construction companies.
