Marine Airbags for ship launching/landing/ slipping:

Marine Ship airbags are also known as air balloon, inflatable bags, roller bags, air lifting bags, salvage bags. Standard air bag size range is 0.8m to 2.0m diameter, with lengths up to 18.0m 'effective length' and even more.

Ship launching airbags are also known as inflatable marine airbags, roller bags, air lift bags, and salvage bags. Airbags are used for ship launching, pulling, lifting, loading, and floating. They are widely used in cargo boat launching and landing, lifting and moving sunken ships, and salvaging stranded boats. Air bags have the benefit of not only saving labor and time, but investment costs. Additionally they are flexible, portable, and dependable.

1. Construction Features of Airbags

Marine Airbags have the best designed structure which consists of five different functional membranes in rubber layers.

1) Outer Rubber Layer

The outer rubber layer that covers the outside of marine airbag to protect under layers from abrasion and other external forces. This compound has sufficient tensile and tearing strength to withstand any condition and hard usage.

2) Inner Rubber Layer

The inner rubber layer seals pressurized air inside marine airbags.

3) Synthetic-Tire-Cord Layer as Reinforcement

The reinforcement cord layers, which are made of synthetic-tire-cord commonly used in tires, are arranged at ideal angles to hold the internal pressure and distribute stress evenly. So they can provide strong efficient reinforcement.

2. General Dimensions of Airbags

Diameter: 800mm to 3000mm

Length: 7000mm to 20000mm

In order to confirm airbag’s safety working pressure, we define the number of layers, which means the number of synthetic-tire-cord layers. Normally we offer marine airbags with 3, 4, 5, 6, 7, 8, 9 layers. Other types are available upon request.

3. Performance Calculation Principle of Airbags

The bearing capacity of marine airbags was calculated based on the working pressure, contact area. Herein, working pressure was got upon the burst pressure and safety working factor.

Because of the flexibility of marine airbag the contact area will be affected by some terms which include the carried ship condition, the different position from gravity center during the process of ship launching and pulling. So the bearing capacity of airbags will vary as well as the contact area.

The approximate bearing capacity can be calculated as follows:

F=PS

S=π x (D1-D2)/2

Where: F: Bearing capacity

P: Inner pressure

S: Contact area

D1: Diameter of airbags when free of loat

D2: Working height of airbags when loaded