The role of marine airbags in the process of ship launching

Marine airbags play a crucial role in launching ships safely and efficiently. This method—using ship airbags and marine rubber airbags—is a game-changer for shipyards, especially for large ships and heavy vessels.

If you’re a shipyard, a ship manufacturer, or a port looking for a flexible, reliable, and cost-effective launching method, ship airbags might be your best solution.
Read on to discover how you can leverage their benefits for your operations.

Why Is This Issue So Important?

Picture this: you’re launching a heavy ship weighing hundreds or even tens of thousands of tons. Without proper methods, small mistakes can cause damage to the hull, costing a lot in repairs or even causing a catastrophic incident.
This is why the ship launching process with airbags is a flexible, cost-effective, and reliable solution for many shipyards today.

What Are Marine Airbags?

Marine airbags are heavy-duty rubber bladders that aid a ship’s descent into the water.
Instead of employing traditional docks or heavy cranes, these airbags enable a smooth and gentle launch by reducing resistance and evenly spreading pressure.

How Do Marine Airbags Support Safe Ship Launching?

Using ship airbags and marine rubber airbags brings many advantages:

The process is low-cost, flexible, and simple.
The pressure on the bottom of the ship is small, avoiding damage to its hull and protective paint.
Airbags make repairs much easier afterwards, a significant advantage over docks, where the bottom paint often gets scratched or corroded due to pressure, causing additional repairs in 3–5 years.
The slope for airbag launching is small and easy to control by adding or removing air pressure. This prevents the ship’s stern from bending, a phenomenon frequently seen with traditional methods.

The Process of Ship Launching with Airbags

Ship launching with airbags typically involves the following steps:

1️⃣ Lift the ship up with airbags.
Workers slowly raise the ship off its supports by inflating the airbags underneath.

2️⃣ Release forward lines and let the ship slide forward.
The ship moves forward under its own weight while resting on the airbags.
At this point, gravity, airbag support, and friction guide its movement.
Shipyards can control the pressure in the airbags to keep the ship’s descent smooth.

3️⃣ The ship enters the water.
As the stern reaches the water, its flotation increases due to displacement.
This upward force gradually lifts the stern until the ship floats free from its supports.

4️⃣ The ship floats forward on its own.
Once fully in water, the ship moves forward under its momentum.
This process happens gracefully and safely, reducing stress on the hull and retaining its structural integrity.

A Successful Innovation From China

Ship launching with airbags is a Chinese innovation that first appeared in the 1980s.
Today, thousands of shipyards — ranging from small to large — safely launch their ships with this method.
Some ships weigh hundreds of tons, while others weigh tens of thousands of tons.
Some even reach 70,000 dwt (dead weight tonnage).
This approach requires no permanent docks or extensive civil works, reducing both investment and operational costs.

People Also Ask (Related Questions)

What is a ship airbag used for?
A ship airbag helps launch ships safely and efficiently into the water, reducing pressure on the hull and avoiding damage.

How much weight can a marine airbag carry during ship launching?
Marine airbags can carry ships weighing from a few hundred to tens of thousands of tons, even up to 70,000 dwt.

Are marine rubber airbags reusable?
Yes — marine rubber airbags are reusable. After a launch, you can clean, inspect, and reuse them many times.

What materials are marine airbags made of?
Marine airbags are made from high-strength rubber with multilayer cord reinforcements for maximum load-bearing capacity.

How do ship airbags reduce the risk of hull damage?
Ship airbags evenly distribute pressure and reduce stress, protecting the hull from bending or cracking during launch.