Airbag launching technique was found to be versatile and flexible in marine engineering fields. Airbags can lift up mega heavy like jacks and move it forward,act as pneumatic rollers. Airbags can roll over pits and knuckles, so they have less demands of the ground or ramp. Different from rigid trolleys, airbags can be compressed at different ratio, thus they can absorb the impact energy emerges in some structure launching projects.
Vessel launching is the major application of airbag launching technology. People successfully launched vessels from dirt, beach, gravel ramp with marine airbags but how about to launch a ship from another ship's deck?
In September 2014, Eversafe Marine worked together with Indonesian PMG corporation, launched one 230 feet barge from the deck of one 300 feet barge with marine airbags.
That launched 230 feet barge measured 64 feet by width and 14 feet by depth; the mother barge, measured 300 feet by length, 90 feet by width and 20 feet by depth. Those two barges were built in Nantong Yahua Shipbuilding Corporation, completed at the same time. By airbag launching, the 300' barge entered into water first, the 230' barge was loaded into it with 1200 T floating crane. Then two barges were towed to Indonesia Tarakan.
To roll a vessel into water from another floating vessel is a big challenge, especially when they have close dimensions. Different from jackets launching from launching barge, there are no specially designed swinging arm and ballasting system equipped on barge. During the launch, once 230' barge floats at stern, its bow will drop down and may collide with the increasing bow of 300' barge.
By exhausted calculation, Eversafe team optimized the launch plan again and again to reduce the vessels' impact energy to be minimum. With well arranged marine airbags, the impact energy will be absorbed safely.
On 3rd September, Eversafe team arrived at Tarakan site. The ballasting operation took 4 days, lifting up barge and remove keel blocks took another two days. At noon of 10th September, the final launch started. When the holding wire ropes were cut off, the 230' barge moved with rolling airbags slowly, passed over the mother barge' bow and entered into the sea gently, even no big splash.
The success of launching a vessel from another vessel's deck means a lot: It can be referred for other deck launching projects, such as the jackets launching. It comes to be possible to launch vessels at a remoted area without assistant facilities, only airbags.
Souce from : Eversafe Marine