Marine airbags -Interview with Evergreen Maritime (1)

What were the first uses of marine airbags in the launching of ships?
People can trace the history of airbag ship launching back to 1981 year,over 20 years ago. Xiao Qinghe ship repair and building shipyard,located in Jinan city of Shangdong Province, launched a 60 DWT tank barge with marine airbags on Janu. 20, 1981. Seven marine airbags were employed in that ship launching project,one is 2 meters in diameters and 6 meters long used for elevating and the left six air bags are 0.8 meter and 6 meters long act as the rollers. The initial intention of that ship launching trial is for warfare purpose to develop a prompt,less landform limited ship launching method.

How has the technology advanced since then?
During the past over twenty years, the marine airbag ship launching system make progress not only the airbag but also the ship launching/landing technology.
The first generation airbags use rubber dipped canvas as reinforcement layer , the trunk and two cone-shaped ends are made separatelly. People lapping rubber and dipped canvas to form the air chamber trunk and stick strips to molds to make the air bags’ ends ,then stick them together.
The latest marine airbags use the rubber dipped synthetic-tyre-cords as the reinforcement layers and take the whole-enlacing-technology for manufacture. The trunk and two cone-shaped ends are made at the same time and enlaced together so the whole air bags have no joints. Due to the development of rubber chemistry the performance of rubber employed in the latest air bag is highly enhanced also. The performance of the latest airbag is 15 times of the first generation one with the same specification.
Regarding the launching/landing technology, it developed most during the past 20 years. From the beginning, only small and flat bottom ship located in fabricated slope can be launched with air bags. And now this technology is more flexible and less limited by the ship and landform. Any type of ship DWT below 55,000 at a place with enough launching space to the water can be launched with air bags. And the launching slope even can be aclinic. The air bag ship landing technology developed from applications in some stranded ship salvage projects and then it comes into a cutting edge one especially useful for some marine emergencies.
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