Ship Launching Airbags

Additional information


0.8 ~ 2.5m, or customized diameter


5 ~ 25m, or customized length

Cord Layers Number

4 ~ 12 Layers

Loading Capacity

10 ~ 40 ton/m, or customized capacity


Manufacturer Certificate, BV/ABS/LR/CCS Certificate


QP-ordinary, QG-high-bearing, QS-superhigh bearing


ISO 14409


24 Months

Ship Launching Airbags

Ship Launching Airbags, also known as roller bags or ship launching balloons, are made of heavy-duty synthetic-tire-cord layers with inner and out rubber layers in a long cylindrical balloon shape. Ship launching airbags can be used for the ship launching or ship landing of oil tankers, tugboat or vessels, barges, chemical tankers, tugboats, AHTS vessels, floating docks, and even construction caissons have all been launched using our ship launching rubber airbags. The biggest vessel launched by ship launching airbags up to 100,000DWT.


ship launching relying on ship launching airbags is an innovative ship launching technology, comparing with “end-on launching”, “side ship launching”, “float-out”. This ship launching technology overcomes the restrictions of fixed launching track of side-launch. Ship launching airbags are accepted by more shipyards worldwide because of their advantages of saving time, saving investment, flexibility, safety.

All Doowin Marine ship launching airbags are manufactured and tested fully compliant with ISO 14409:2011 Ships and marine technology — Ship launching airbags. To learn more technology, please kindly refer ISO 17682:2013 Ships and marine technology — Methodology for ship launching utilizing airbags

Construction of Ship Launching Airbags

Ship launching airbags are to be constructed of an out rubber layer, multilayer heavy-duty synthetic-tire-cord layers, and an inner rubber layer vulcanized firmly. Ship launching airbags are cylindrical balloon body, with two conical heads and two end mouths. Airtightness swivel and air inlet kits are screwed with end mouth.

  • Synthetic-tire-cord layer

The Synthetic-tire-cord layer is the reinforcement layer of the ship launching airbags which are made of rubber-coated synthetic-tire-cord fabrics. Many synthetic-tire cord layers are twined at ideal angles by unique and patented “Holistic Wrapping Technology“. To hold the internal pressure and to distribute the stress evenly. We use the 1870 dtex/2 type synthetic-tire-cord fabric. The warp is over 95 cords per 100 mm in width. The breaking strength is more than 310 N per cords.

  • Inner and Outer Rubber

Prior to the airbag production, the outer and inner rubber layers shall be tested to meet the criteria in accordance with the test methods given in the International Standards listed below. The outer rubber layer covers the outside of ship launching airbags. To protects the cord layers from abrasion and other external forces. This compound has sufficient tensile and tear strength to withstand any weather condition and hard usage.

Structure of Ship Launching Airbags


The standard ship launching airbags include the below spares. Ready for use.

  1. The end of the airbag body
  2. End flange (Q235 H.D.G)
  3. Sealing Washer
  4. Three-direction connector at the inflate end (Q235 H.D.G)
  5. 3/4′ Ball Valves at the inflate end (Brass)
  6. Hose connection at the inflate end (Q235)
  7. High-quality Pressure Gauge
  8. 8. End plug at the tightness end (Q235 H.D.G)

Classification of Ship Launching Airbags

Ship Launching air bags are categorized by the following three types according to the bearing capacity, per meter in length. We define the number of layers, which means the number of Synthetic-tyre-cord layers, in order to confirm the Safety Working Pressure. Another type is available upon clients’ request.

  • QP – Ordinary airbag – with 3, 4 or 5 layers of cord fabric.
  • QG – high-bearing capacity –  with 6, 7, or 8 layers of cord fabric.
  • QS – Superhigh-bearing capacity air bag – with 9, 10, or more layers of cord fabrics as custom request.

For example: QG6/1.5×15
QG6: 6 layers cord fabric
1.5: diameter is 1.5m
15: length is 15m

Air Bag Parameter

Ship Launching Airbags Size

Product Name

Ship Launching Marine Rubber Airbags

Diameter (D)

0.8 ~ 2.5m, or customized diameter

Effective Length (EL)

6 ~ 25m, or customized length

Total Length (TL)

7 ~ 27m, or customized length

Loading Capacity

10 ~ 40 ton/m, or customized capacity

Model of Airbags

QP-ordinary, QG-high-bearing, QS-superhigh bearing

Ship Launching Airbags Features & Advantages

Superior Manufacturing & Quality Control Processes from the selection of raw materials to the highly skilled production process.


High Lifting Capacity

Air bags create high lifting capacity with safer low pressure. One air bag can lift 300~500 ton.

High Tensile Strength

Heavy-duty synthetic-tire-cord layers are the framework material. It can bear high working pressure.

Resistant to Abrasion

Rubber airbags have 6~12 plies reinforcement layers to withstand most abrasion and puncture.

Ship Launching Airbags Performance

Superior Manufacturing & Quality Control Processes from the selection of raw materials to the highly skilled production process


Ship Launching Airbags Inspection

We test and inspect all the ship launching airbags purchased based on the test items indicated below:

•  The appearance of each of our ship launching airbags is smooth, glossy, and without blemishes such as crack, blister, delamination, pits, or impurities.
•  The length and diameter of each ship launching airbags are measured under the rated working pressure and are within ±3%.
•  The gas-tightness is tested without carrying any load as per ISO 14409. The pressure loss is less than 5% of rated working pressure within 1 hour.


All Doowin Marine ship launching airbags are manufactured and insepcted fully compliant with ISO 14409 “Ships and marine technology – ship launching air bags“, certificated by CCS, LR, BV. There are two more China industrial standards and one ISO standard for ship launching airbags:

CB/T 3837-1998 Technological Requirements for ship Upgrading or Launching Relying on Airbags (Shipbuilding Industry Standard, PRC)
CB/T 3795-1996 / CB/T 3795-2009 Air bag for ship up to or down to launching way (Shipbuilding Industry Standard, PRC)
— ISO 17682 Ship sand marine technology —Methodology for launching ship utilizing air bags

All Categories

Marine Rubber Airbags


The weight of ship launching airbags is calculated by airbag surface area. When you care too much about weight, you may be misled by some manufacturers. Please remember “It’s not that the heavier the airbag, the better the quality. Weight is not a good indicator of quality.”

It is very easy to distinguish used and new airbags. If there are abrasions on the airbags body, then it is used one. For the new airbags, it’s surface maybe looks ugly and dirty. It is because we use French chalk in the vulcanization process. When the water vapor in the vulcanization tank is mixed with French chalk, the surface will appear very dirty.

Our unique overall winding technology is different from the current mainstream airbag production technology. We innovate and improve on the basis of mainstream production technology. The airbag produced by the optimal winding angle technology can exert the maximum effect of the material, save the cost, and have a stronger lifting force.

Marine rubber airbags are not single-use products. It can be used for many times. But cannot define the exact number. General speaking marine airbags have 5~8 years lifespan under the correct usage and proper maintenance.

Marine rubber airbags are not single-use products. It can be used for many times. But cannot define the exact number. General speaking marine airbags have 5~8 years lifespan under the correct usage and proper maintenance.

The ship launching airbags price is calculated by the airbag’s surface area, not weight. Rubber airbag has two cone shape ends. But we normally, make the airbags as cylindrical shape to calculate its surface area. Its calculate formal is S=π x Diameter x (Diameter+Effective Length) x layer numbers. Then, multiply the surface area by the unit price. The unit surface price is quite different for different factories, generally it is in the scope of USD4 to USD8 for each square meters.


Our engineers are now available for a free consultation to help you find the right equipment for your project.

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