1L natural rubber air bag
The rubber air bag was invented by experienced engineers in 1986 to launch the ship in the river.
After many years of technology accumulation, the rubber air bag could launch the ship, whose self weight is more than 9000 T.
We are able to make the customized air bag. The diameter could be from 0.3M to 2.5M. The length could be from 1M to 24M. Our biggest specification is D2.5M X L 24M.
The air-bag application method for common medium ship launching is described as follows:
Based on calculation result, enough rolling air bags and lifting air-bags, towing machines and air compressors are prepared. Before using, an air bag shall be inflated and tested without load. In case of air leakage, the air bag must be repaired before using.
The roads for ship movement, including the road from the shipbuilding berth to ramp, must be cleaned up and flattened. Sundries must be removed from the roads, especially sharp iron nails and stone on the road, to avoid piercing the air bag. The ramp shall be enough long and wide in water.
All the protruding sharp corners and burrs on casting like"A" bracket and stern post and so on shall be ground flush/
Fasten the hull with the steel cable of traction winch.
Close all the sea chest valves on the ship, fix the rudder and propeller.
There are many ways to remove all blockes and fill in the rolling air bag.
Adjust pressure in the air bag so that the bottom can be lowered to appropriate working height. Make sure that the bottom will not touch the ground while moving the ship. For average small sized ship, the working height could be chosen
Within the range of 0.2-0.3M.
All air bags shall be pointed at the center of the ship and perpendicular to the launching direction.
Start the traction winch to release steel cable slowing followed by slow movement of the ship. When the forefront air bag located in the front part separates from the bottom, it shall be put into the stern immediately and fill in the air bag according to the arrangmetn space of the air bag defined in the calculations.
Repeat the above process to move the ship to waterside slowly. When the air bag cannot be filled in, block the river and no ship is allowed to pass.
Evacuate personnel in the dangerous zone, inform staff on the ship to get ready. When conditions such as water depth and so on are gnough. Cut cable or unhook so that the ship can launch quickly. If the river is too narrow to realize quick launching, release the cable slowly by traction winch to launch the ship slowly.
For large ships, it's necessary to install anti-skip device.
Collect air bags.
Storage of the air bag
If the air bag will not use for quite a long time, it shall be washed and dried, filled with French chalk inside and coated with French chalk outside as well as put in dry, shady and ventilated place in the room.
The storage air bag shall be far away from the heat source.
The air bag can not contact with acid, alkali, grease and organic solvents.
The air bag should be stretched flat when not used. It is not allowed to pile up and stack heavy object on the air bag.
Quality guarantee
Our air bag meets the quality requirements of CB/T3795-1996", air bag for the up to-slipway and launching of the ship".
Should quality problem happen within a year, it is guaranteed to change or refund on the condition that the transporation, storage and working conditions are up to the regulations.
| Some normal sizes of our lift bags , customized sizes are also available |
| Diameter(m) |
Effective Length(m) |
Layer |
Pressure(MPa) |
| 1 |
10 |
5~6 |
0.07~0.10 |
| 1 |
12 |
5~6 |
0.07~0.10 |
| 1 |
15 |
5~6 |
0.07~0.10 |
| 1.2 |
10 |
5~6 |
0.08~0.12 |
| 1.2 |
12 |
5~6 |
0.08~0.12 |
| 1.2 |
15 |
5~6 |
0.08~0.12 |
| 1.5 |
12 |
5~8 |
0.08~0.16 |
| 1.5 |
15 |
5~8 |
0.08~0.16 |
| 1.5 |
18 |
5~8 |
0.08~0.16 |
| 1.5 |
20 |
5~8 |
0.08~0.16 |
| 1.5 |
24 |
5~8 |
0.08~0.16 |
| 1.8 |
12 |
5~8 |
0.08~0.15 |
| 1.8 |
15 |
5~8 |
0.08~0.15 |
| 1.8 |
18 |
5~8 |
0.08~0.15 |
| 1.8 |
20 |
5~8 |
0.08~0.15 |
| 1.8 |
24 |
5~8 |
0.08~0.15 |
| 2 |
18 |
6~10 |
0.08~0.18 |
| 2 |
20 |
6~10 |
0.08~0.18 |
| 2 |
24 |
6~10 |
0.08~0.18 |
| 2.5 |
18 |
7~10 |
0.07~0.13 |
| 2.5 |
20 |
7~10 |
0.07~0.13 |
| 2.5 |
24 |
7~10 |
0.07~0.13 |
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